US20110017642A1

US20110017642A1 - System and method for converting material comprising bitumen into light hydrocarbon liquid product

Info

Publication number: US20110017642A1
Application number: US12/509,298
Authority: US
Inventors: Willem P.C. Duyvesteyn
Original assignee: Marathon Oil Canada Corp
Current assignee: Marathon Oil Canada Corp
Priority date: 2009-07-24
Filing date: 2009-07-24
Publication date: 2011-01-27
Also published as: CA2769078A1; WO2011011288A1

Abstract

Various methods and systems for obtaining light hydrocarbon distillate from material comprising bitumen are disclosed. The method may include a primary leaching or extraction process that separates most of the bitumen from the material comprising bitumen and results in a bitumen-enriched solvent phase and first solvent-wet tailings. The bitumen-enriched solvent phase includes mainly solvent and bitumen. The bitumen-enriched solvent phase is injected into a nozzle reactor wherein at least a portion of the bitumen is cracked into light hydrocarbon distillate. The light hydrocarbon distillate may then be used as solvent in the first primary leaching or extraction step.

Description

BACKGROUND

Bitumen is an extremely heavy type of crude oil that is often found in naturally occurring geological materials such as tar sands, black shales, coal formations, and weathered hydrocarbon sources contained in sandstones and carbonates. Bitumen may be described as flammable brown or black mixtures or tar-like hydrocarbons derived naturally or by distillation from petroleum. Bitumen can be in the form of a viscous oil to a brittle solid, including asphalt, tars, and natural mineral waxes. Substances containing bitumen may be referred to as bituminous, e.g., bituminous coal, bituminous tar, or bituminous pitch. At room temperature, the flowability of bitumen is much like cold molasses. Bitumen may be processed to yield oil and other commercially useful products, primarily by cracking the bitumen into lighter hydrocarbon material. A comparison between the properties of Athabasca-type bitumen and an average crude oil is presented in the following table.


Property (typical)	Bitumen	Crude Oil

Specific gravity - g/cc	1.05	0.85
Viscosity @ 38 deg C. - cp	750,000	<200
Carbon - %	83	86
Hydrogen - %	10.5	13.5
H/C mol ratio	1.5	1.9
Sulfur	5.0	<0.5
C5 asphaltenes - %	17	<5
Resins - %	34	<20
Aromatics - %	34	>30
Saturates - %	15	>35
Conradson carbon - %	15	<5

As noted above, tar sands represent one of the well known sources of bitumen. Tar sands typically include bitumen, water and mineral solids. The mineral solids can include inorganic solids such as coal, sand, and clay. Tar sand deposits can be found in many parts of the world, including North America. One of the largest tar sands deposits is in the Athabasca region of Alberta, Canada. In the Athabasca region, the tar sands formation can be found at the surface, although it may be buried as deep as two thousand feet below the surface overburden. Tar sands deposits are measured in barrels equivalent of oil. It is estimated that the Athabasca tar sands deposit contains the equivalent of about 1.7 to 2.3 trillion barrels of oil. Global tar sands deposits have been estimated to contain up to 4 trillion barrels of oil. By way of comparison, the proven worldwide oil reserves are estimated to be about 1.3 trillion barrels.
The bitumen content of tar sands varies from approximately 3 wt % to 21 wt %, with a typical content of approximately 12 wt %. As such, an initial step in deriving oil and other commercially useful products from bitumen typically requires extracting the bitumen from the naturally occurring geological material. In the case of tar sands, this may include separating the bitumen from the mineral solids and other components of tar sands.
One conventional process includes mixing the tar sands ore with hot water to form a bitumen enriched froth. The froth is separated and further processed to isolate the bitumen product. Conventional water-based extraction technologies are capable of separating bitumen from higher grade ore but are unable to economically separate bitumen from lower grade ore. Unfortunately, this means that a significant amount of tar sand ore is not capable of being processed to recover the otherwise valuable bitumen.
Another problem with conventional water based extraction technologies is the low overall recovery rate of bitumen. Unfortunately, some conventional extraction processes discharge part of the bitumen in the ore with the tailings. Other conventional processes discharge a significant part of the bitumen in the ore as an asphaltene precipitate with the tailings. Not only does this reduce the efficiency of the extraction process due to lower recoveries, but it also presents potential environmental problems that must be addressed.
Many conventional methods for obtaining bitumen from tar sands also have serious technical limitations. For example, many conventional methods use water, which can cause clays in the tar sands to swell and interfere with processing equipment. In addition, some conventional methods result in the undesirable precipitation of soluble asphaltenes.
One example of a conventional method is described in U.S. Pat. No. 4,046,668 (the '668 patent). The '668 patent discloses the extraction of hydrocarbons from tar sands with a mixture of light naphtha having from 5 to 9 carbon atoms per molecule and methanol. The method disclosed in the '668 patent is limited, in part, because it requires the simultaneous use of two solvents, which increases processing costs and is less efficient in terms of bitumen recovery and solvent plus bitumen content of the final tailings that are disposed.
U.S. Pat. No. 4,347,118 (the '118 patent) discloses a method in which pentane is used to extract bitumen from tar sands. The method disclosed in the '118 patent requires the use of two fluidized bed drying zones. Operation of these fluidized bed drying zones requires a large amount of energy, limiting the efficiency of the overall method. Furthermore, the pentane solvent does not solubilize the asphaltene fraction of the bitumen that is not pentane soluble. Thus, this fraction of the bitumen is discharged with the tailings. For Athabasca type bitumen, this may range from 20 wt % to 40 wt % of the total initial hydrocarbon content of the tar sands.
U.S. Pat. No. 5,143,598 (the '598 patent) discloses a method that includes adding heptane to tar sands to form a bitumen-rich heptane phase and then displacing the bitumen-rich heptane phase with water. This method utilizes steam vaporization and condensation, which are low-efficiency processes. Also, the use of heptane, a non-aromatic solvent, in this method can result in the precipitation of the heptane insoluble asphaltene fraction present in the bitumen phase. The heptane insoluble asphaltene fraction is discharged with the tailings. In addition, using water not only generates large amounts of aqueous waste but also creates oil-water emulsions that are very difficult to breakdown. The use of water can also introduce undesirable impurities into bitumen, such as chlorine, and can result in undesirable swelling of clays in the tar sands. Furthermore, the bitumen recovered by this method typically has a low purity and requires additional processing, such as by centrifugation. This further increases the cost of the overall recovery process.
The above issues may be mitigated or eliminated by separating bitumen from a material comprising bitumen by using a two step extraction process as disclosed in co-pending U.S. application Ser. Nos. 12/041,554 and 11/249,234, both of which are incorporated herein by reference in their entireties. The method generally comprises a first extraction step wherein material comprising bitumen is mixed with a first solvent, and the resulting mixture is separated into a bitumen-enriched solvent phase and first solvent-wet tailings. The majority of the bitumen in the material comprising bitumen is contained in the bitumen-enriched solvent phase. The first solvent may be, for example, a light aromatic solvent. The bitumen-enriched solvent phase may then undergo a further separation wherein the bitumen is separated from the first solvent. In a second extraction step, the first solvent-wet tailings are mixed with a second solvent, and the resulting mixture is separated into a first solvent-enriched second solvent phase and second solvent-wet tailings. The majority of the first solvent in the first solvent-wet tailings are contained in the first solvent-enriched second solvent phase. The second solvent may be a volatile hydrocarbon solvent. The second solvent-wet tailings are then treated to remove any most, if not all, of the second solvent contained therein. The bitumen obtained from the bitumen-enriched solvent phase may then be subjected to further processing to upgrade the material into useful fuel products.
As can be seen from the above description, this two-step extraction process requires various supplies of solvents in order to carry out the separation of bitumen from material comprising bitumen. Typically, the solvents will need to be obtained from a third party, thus increasing the overall cost of the process and making the manufacturing process dependent on an outside vendor. Factors such as these will tend to inflate the price of oil derived from material comprising bitumen according to the two step extraction process.

SUMMARY

Disclosed are embodiments of a method and system for obtaining light hydrocarbon liquid distillate from material comprising bitumen. The disclosed method and system may include one or more solvent extraction steps to separate bitumen from the material comprising bitumen, a cracking step for cracking bitumen inside a nozzle reactor, and a recycling step to use the light hydrocarbon liquid distillate produced from cracking the bitumen in the nozzle reactor as the solvent in at least one of the extraction steps. In some embodiments, such a method and system may thereby become an essentially solvent free and self-sustaining method and system.
In some embodiments, a method includes forming a first mixture by mixing a first quantity of material comprising bitumen with a first solvent. The first mixture includes a bitumen-enriched solvent phase. The method also includes separating the bitumen-enriched solvent phase from the first mixture. Separation of the bitumen-enriched solvent phase results in the first mixture becoming first solvent-wet tailings. The bitumen-enriched solvent phase includes bitumen component and the first solvent-wet tailings include a first solvent component. The method also includes forming a light hydrocarbon liquid distillate and a non-participating hydrocarbon stream by cracking the bitumen component of the bitumen-enriched solvent phase in a first nozzle reactor. The method can also include mixing the light hydrocarbon distillate with a second quantity of material comprising bitumen.
In some embodiments, a method includes forming a first mixture by mixing a first quantity of material comprising bitumen with a first solvent. The first mixture includes a bitumen-enriched solvent phase. The method also includes separating the bitumen-enriched solvent phase from the first mixture. Separation of the bitumen-enriched solvent phase results in the first mixture becoming first solvent-wet tailings. The bitumen-enriched solvent phase includes a bitumen component and a primary first solvent component, and the first solvent-wet tailings include a first solvent component. The method also includes separating the primary first solvent from the bitumen-enriched solvent phase. Separation of the primary solvent from the bitumen-enriched solvent phase results in the isolation of the bitumen component of the bitumen-enriched solvent phase. The method can further include producing an asphaltene stream by deasphalting the bitumen component. The method may also include forming a light hydrocarbon liquid distillate and a non-participating hydrocarbon stream by cracking the asphaltene stream in a first nozzle reactor. Further, the method can also include mixing the light hydrocarbon distillate with a second quantity of material comprising bitumen.
In some embodiments, a method includes solvent extracting a first quantity of material comprising bitumen with at least one solvent to separate bitumen from the first quantity of material comprising bitumen. The method also includes cracking the separated bitumen to form a light hydrocarbon liquid distillate. The method can also include solvent extracting a second quantity of material comprising bitumen with the light hydrocarbon liquid distillate to separate bitumen from the second quantity of material comprising bitumen.
In some embodiment, a method includes mixing a first quantity of material comprising bitumen with a first solvent. The method also includes separating a bitumen-enriched solvent phase from a first result of mixing the first solvent with the first quantity of material comprising bitumen. Additionally, the method includes separating a first solvent component from the bitumen-enriched solvent phase. The method can also include deasphalting a second result of separating the first solvent component from the bitumen-enriched solvent phase. Furthermore, the method includes feeding a third result of deasphalting the second result into a nozzle reactor. The method also includes mixing a portion of a fourth result of feeding the third result into a nozzle reactor with a second quantity of material comprising bitumen.
In some embodiments, a method includes mixing a first quantity of material comprising bitumen with a first solvent. The method can also include separating a bitumen-enriched solvent phase from a first result of mixing the first solvent with the first quantity of material comprising bitumen. The method can also include separating a first solvent component from the bitumen-enriched solvent phase. The method further includes deasphalting a second result of separating the first solvent component from the bitumen-enriched solvent phase. Additionally, the method includes feeding a third result of deasphalting the second result into a nozzle reactor. Furthermore, the method includes mixing a portion of a fourth result of feeding the third result into a nozzle reactor with a second quantity of material comprising bitumen.
It is to be understood that the foregoing is a brief summary of various aspects of some disclosed embodiments. The scope of the disclosure need not therefore include all such aspects or address or solve all issues noted in the background above. In addition, there are other aspects of the disclosed embodiments that will become apparent as the specification proceeds.
The foregoing and other features, utilities, and advantages of the subject matter described herein will be apparent from the following more particular description of certain embodiments as illustrated in the accompanying drawings. In this regard, it is to be understood that the scope of the invention is to be determined by the claims as issued and not by whether given subject includes any or all features or aspects noted in this Summary or addresses any issues noted in the Background.

BRIEF DESCRIPTION OF THE DRAWINGS

The preferred and other embodiments are disclosed in association with the accompanying drawings in which:

FIG. 1 is a flow chart depicting a method for obtaining bitumen;

FIG. 2 is a cross-section view of one embodiment of a nozzle reactor;

FIG. 3 is a flow chart depicting a method for obtaining bitumen;

FIG. 4 is a schematic diagram of a system and method for obtaining bitumen;

FIG. 5 is a schematic diagram of a system and method for obtaining bitumen;

FIG. 6 is a schematic diagram of a system and method for obtaining bitumen; and

FIG. 7 is a schematic diagram of a system and method for obtaining bitumen;

DETAILED DESCRIPTION

Before describing the details of the various embodiments herein, it should be appreciated that the terms “solvent,” “a solvent” and “the solvent” include one or more than one individual solvent compound unless expressly indicated otherwise. Mixing solvents that include more than one individual solvent compounds with other materials can include mixing the individual solvent compounds simultaneously or serially unless indicated otherwise. It should also be appreciated that the term “tar sands” includes oil sands. The separations described herein can be partial, substantial or complete separations unless indicated otherwise. All percentages recited herein are weight percentages unless indicated otherwise.
Tar sands are used throughout this disclosure as a representative material comprising bitumen. However, the methods and system disclosed herein are not limited to processing of tar sands. Any material comprising bitumen may be processed by the methods and systems disclosed herein.
As shown in FIG. 1, a first embodiment of a method for obtaining bitumen from material comprising bitumen includes a first step 100 of mixing a first quantity of material comprising bitumen with a first solvent to form a first mixture including a bitumen-enriched solvent phase, a step 110 of separating the bitumen enriched solvent phase from the first mixture and thereby producing first solvent-wet tailings, a step 120 of cracking the bitumen component of the bitumen-enriched solvent phase inside a first nozzle reactor to form a light hydrocarbon liquid distillate and a non-participating hydrocarbon stream, and a step 130 of mixing the light hydrocarbon liquid distillate with a second quantity of material comprising bitumen.
Step 100 of mixing a first quantity of material comprising bitumen with a first solvent to form a first mixture represents a solvent extraction step (also sometimes referred to as dissolution, solvation, or leaching). Solvent extraction is a process of separating a substance from a material by dissolving the substance of the material in a liquid. In this situation, the material comprising bitumen is mixed with one or more solvents to dissolve bitumen in the solvent and thereby separate it from the other components of the material comprising bitumen (e.g., the mineral solids of tar sands).
The first solvent used in mixing step 100 may include a hydrocarbon solvent. Any suitable hydrocarbon solvent or mixture of hydrocarbon solvents that is capable of dissolving bitumen may be used. In certain embodiments, the hydrocarbon solvent is a hydrocarbon solvent that does not cause asphaltene precipitation. The hydrocarbon solvent or mixture of hydrocarbon solvents can be economical and relatively easy to handle and store. The hydrocarbon solvent or mixture of hydrocarbon solvents may also be generally compatible with refinery operations.
In some embodiments, the first solvent may be a light aromatic solvent. The light aromatic solvent may be an aromatic compound having a boiling point temperature less than about 400° C. at atmospheric pressure. In certain embodiments, the light aromatic solvent used in the first mixing step is an aromatic having a boiling point temperature in the range of from about 75° C. to about 350° C. at atmospheric pressure, and more specifically, in the range of from about 100° C. to about 250° C. at atmospheric pressure.
It should be appreciated that the light aromatic need not be 100% aromatic compounds. Instead, the light aromatic solvent may include a mixture of aromatic and non-aromatic compounds. For example, the first solvent can include greater than zero to about 100 wt % aromatic compounds, such as approximately 10 wt % to 100 wt % aromatic compounds, or approximately 20 wt % to 100 wt % aromatic compounds. In one example, the aromatic compounds include naphthalenes and/or cyclo-alkanes. A general chemical formula for cyclo-alkanes is C_nH_2(n+1−g), where n is the number of C atoms and g is the number of rings in the molecule.
Any of a number of suitable aromatic compounds may be used as the first solvent. Examples of aromatic compounds that can be used as the first solvent include benzene, toluene, xylene, aromatic alcohols and combinations and derivatives thereof. The first solvent can also include compositions, such as kerosene, diesel (including biodiesel), gas oil (e.g., light gas oil (gas oil having boiling point temperature in the range of from 200° C. to 300° C.) or medium light gas oil (gas oil having boiling point temperature in the range of from 240° C. to 350° C.)), light distillate (distillate having boiling point temperature in the range of from 140° C. to 260° C.), commercial aromatic solvents such as Solvesso 100, Solvesso 150, and Solvesso 200 (also known in the U.S.A. as Aromatic 100, 150, and 200, including mainly C₁₀-C₁₁aromatics, and produced by ExxonMobil), and/or naphtha. Naphtha, for example, is particularly effective at dissolving bitumen and is generally compatible with refinery operations. Some examples of kerosene include hydrocarbons having between 9 and 15 carbons per molecule. Some examples of diesel include hydrocarbons having between 15 and 25 carbons per molecule. Some examples of light or medium light gas oil include hydrocarbons having between 13 and 20 carbons per molecule. Some examples of naphtha include hydrocarbons having between 4 and 12 carbons per molecule. These examples are not intended to limit the general meanings of the respective terms.
The material comprising bitumen used in the mixing step may be any material that includes bitumen. In certain embodiments, the material comprising bitumen includes any material including 3 wt % or more of bitumen. Exemplary materials comprising bitumen include, but are not limited to, tar sands, black shales, coal formations, and weathered hydrocarbon sources contained in sandstones and carbonates. The material comprising bitumen may be obtained by any known means for obtaining material comprising bitumen, such as by surface mining, underground mining, or any in situ extraction methods, such as vapor extraction (Vapex) and steam assisted gravity drainage (SAGD) extraction, and other solvent and thermal extraction techniques.
The step 100 of mixing a first quantity of material comprising bitumen and a first solvent can be performed as a continuous, batch, or semi-batch process. Continuous processing is typically used in larger scale implementations. However, batch processing may result in more complete separations than continuous processing.
The material comprising bitumen and the first solvent may be mixed by any suitable manner for mixing two materials for any suitable period of time. The mixing 100 of the material comprising bitumen and the first solvent is preferably carried out to the point of dissolving most, if not all, of the bitumen contained in the material comprising bitumen. In certain embodiments, the material comprising bitumen and the first solvent are mixed in a vessel to dissolve the bitumen and form the first mixture. The vessel can be selectively opened or closed. The vessel used for mixing may also contain mechanisms for stirring and mixing solvent and material comprising bitumen to further promote dissolution of the bitumen in the first solvent. For example, powered mixing devices such as a rotating blade may be provided to mix the contents of the vessel. The vessel may also rotate about its axis to provide mixing, such as in a ball mill, or may be a grinding mill, such as described in U.S. Pat. No. 5,512,008.
The presence of water in the material comprising bitumen may impact the amount of power to be used when mixing the first solvent and material comprising bitumen to dissolve the bitumen in the first solvent. Material comprising bitumen may include from about 2 wt % to about 10 wt % water, and excessive mixing with the first solvent can result in the formation of certain water-solvent emulsions that can be quite stable. By controlling the amount of power used when mixing and the mixing time, the water content of the material comprising bitumen will stay associated with the non-bitumen components of the material comprising bitumen. Any mixing regime that produces a Reynolds number in excess of 10,000 would likely result in the formation of certain water-solvent emulsions. Additionally, it is expected that with tar sand clumps of 3 inches or less, the mixing time should be limited to less than 30 minutes to avoid emulsion formation.
In certain embodiments, material comprising bitumen and the first solvent are mixed by virtue of the manner in which the material comprising bitumen and the first solvent are introduced into the vessel. In this regard, the first solvent may be introduced into a vessel already containing material comprising bitumen at a high velocity, thereby effectively agitating and mixing the contents of the vessel. Conversely, the material comprising bitumen may be introduced into a vessel already containing first solvent. In some embodiments, the first solvent and material comprising bitumen are jointly introduced into a rotating mill with a ball charge or a non-rotating vibratory mill with charge of grinding or mixing media.
The amount of the first solvent added to the material comprising bitumen is a sufficient amount to effectively dissolve at least a portion, or desirably all, of the bitumen in the material comprising bitumen. In some embodiments, the amount of the first solvent mixed with the material comprising bitumen is approximately 0.5 to 3.0 times the amount of bitumen by volume contained in the material comprising bitumen, approximately 0.6 to 2.0 times the amount of the bitumen by volume contained in the material comprising bitumen, or approximately 0.75 to 1.5 times the amount of bitumen by volume contained in the material comprising bitumen.
It should be noted that the ratio of the first solvent to bitumen is affected by the amount of bitumen in the material comprising bitumen. For example, when the material comprising bitumen is a high grade tar sands ore (e.g., greater than 12 wt % bitumen), the high grade tar sands ore can be processed with a solvent to bitumen weight ratio as low as 2:1. However lower grade tar sands ore (e.g., 6 wt % bitumen) may be processed with a solvent to bitumen ratio greater than 3:1 to provide sufficient liquid to fill up the open space between the particles.
The first mixture of the first solvent and the material comprising bitumen generally results in the formation of a bitumen-enriched solvent phase within the first mixture, with the majority of the bitumen from the material comprising bitumen dissolved in the bitumen-enriched solvent phase. In certain embodiments, 90%, preferably 95%, and most preferably 99% or more of the bitumen in the material comprising bitumen is dissolved in the first solvent and becomes part of the bitumen-enriched solvent phase.
Step 100 of mixing first solvent and material comprising bitumen may be performed at any suitable temperature and pressure. In certain embodiments, it may be desirable to perform the mixing step at an increased pressure to maintain the first solvent as a liquid during the mixing. Additionally, performing the mixing step at higher temperatures may allow for the use of a wider range of suitable first solvents (e.g., aromatic solvents having a boiling point temperature higher than 400° C.). Mixing at elevated temperatures may also enhance the kinetics of the dissolution process.
In step 110, the bitumen-enriched solvent phase is separated from the first mixture, Separation of the bitumen-enriched solvent phase from the first mixture results in the first mixture becoming first solvent-wet tailings. Any suitable process for separating the bitumen-enriched solvent phase from the first mixture may be used, such as by filtering (including pressure and vacuum filtration), settling and decanting, or by gravity or gas overpressure drainage.
Separation of the bitumen-enriched solvent phase preferably does not include the separation of the water content of the first mixture. Because the water is heavier than the first solvent (specific gravity of 1 for water versus specific gravity of ˜0.8 for first solvent), the water will likely not be removed from the first mixture when the bitumen-enriched solvent phase is separated by the method disclosed above.
In certain embodiments, the bitumen-enriched solvent phase removed from the first mixture includes from about 5 wt % to about 50 wt % of bitumen and from about 50 wt % to about 95 wt % of the first solvent. The bitumen-enriched solvent phase includes little or no non-bitumen components of the material comprising bitumen (e.g., mineral solids). The first solvent-wet tailings created by removing the bitumen-enriched solvent phase from the first mixture may include from about 75 wt % to about 95 wt % non-bitumen components of the material comprising bitumen and from about 5 wt % to about 25 wt % first solvent. The first solvent component of the first solvent-wet tailings represents first solvent mixed with the material comprising bitumen but which is not removed from the first mixture during separation step 110. This first solvent component of the first solvent-wet tailings may have bitumen dissolved therein. Accordingly, in certain embodiments, the first solvent-wet tailings may include from about 50 wt % to about 99 wt % of bitumen.
The vessel for mixing mentioned previously may function as both the mixer and a separator for separating the bitumen-enriched solvent phase from the first mixture. Alternatively, separate vessels can be used for mixing and separating, wherein the first mixture is transported from the mixing vessel to a separation vessel. In certain embodiments, the vessel may be divided into sections. One section may be used to mix the material comprising bitumen and the first solvent and another section may be used to separate the bitumen-enriched solvent phase and the first solvent-wet tailings.
The separation of the bitumen-enriched solvent phase from the first mixture can be performed as a continuous, batch, or semi-batch process. Continuous processing is typically used in larger scale implementations. However, batch processing may result in more complete separations than continuous processing.
Separation of the bitumen-enriched solvent phase from the first mixture by any of the above-described methods may be preceded or followed by applying pressurized gas over the first mixture. Applying a pressurized gas over the first mixture facilitates the separation of the bitumen-enriched solvent phase from the non-bitumen components of the first solvent-wet tailings. Liberated bitumen-enriched solvent phase can then be removed by applying additional first solvent to the first solvent-wet tailings as described in greater detail below. The addition of additional first solvent can, in some embodiments, displace the liberated bitumen-enriched solvent phase from the first solvent-wet tailings. Applying a pressurized gas over the first mixture may also provide a driving force for moving bitumen-enriched solvent phase out of the first mixture without the need for adding additional first solvent. Any suitable gas may be used. In certain embodiments, the gas is nitrogen, carbon dioxide or steam. The gas may also be added over the first mixture in any suitable amount. In certain embodiments, 62.5 ft³to 375 ft³of gas per ton of material comprising bitumen is used. This is equivalent to a range of about 4.5 liters to 27 liters of gas per liter of material comprising bitumen. In some embodiments, 125 ft³of gas per ton of material comprising bitumen is used.
In certain embodiments, the bitumen-enriched solvent phase is separated from the first mixture by filtering the first mixture with a plate and frame-type filter press. Any plate and frame-type filter press known to those of ordinary skill in the art may be used. An exemplary plate and frame-type filter press suitable for use in this method is described in U.S. Pat. No. 4,222,873. Generally, the first mixture is pumped into frame chamber located between two filter plates. The first mixture fills the frame chamber and the liquid component of the first mixture migrates out of the frame chamber through the filter cloths of each filter plate, thereby separating the liquid component of the first mixture from the solid component of the first mixture. In this case, the liquid component is the bitumen-enriched solvent phase (i.e., first solvent having bitumen dissolved therein) and the solids component is the first solvent-wet tailings. The bitumen-enriched solvent phase that has passed out of the frame chamber is routed out of the plate and frame-type filter press while the first solvent-wet tailings are left behind in the frame chamber.
When utilizing a plate and frame-type filter press to separate the first mixture, pressurized gas may be injected into the frame chamber after the frame chamber has been filled with the first mixture to promote the separation of the bitumen-enriched solvent phase from mineral solids in the first mixture and the displacement of the bitumen-enriched solvent phase from the first mixture. The introduction of pressurized gas into the frame chamber may proceed according to the details provided above for applying pressurized gas over a first mixture.
In certain embodiments, step 110 includes a second separation stage in addition to the separation described above. When the bitumen-enriched solvent phase is removed from the first mixture, a residual amount of bitumen-enriched solvent phase may remain in the first mixture. Because the first mixture includes a residual amount of bitumen-enriched solvent phase, the first mixture is now considered first solvent-wet tailings. Accordingly, the second separation stage is performed to remove the residual bitumen-enriched solvent phase from the first solvent-wet tailings.
The second separation stage may be performed by adding a second quantity of first solvent to the first solvent-wet tailings. The addition of a second quantity of first solvent displaces the residual bitumen-enriched solvent phase and thereby forces the residual bitumen-enriched solvent phase out of the first solvent-wet tailings. Some of the second quantity of the first solvent may remain in the first solvent-wet tailings, but little to no bitumen-enriched solvent phase remains. In this manner, the first solvent-wet tailings remain first solvent-wet tailings even after the second stage of separation, although the first solvent-wet tailing become essentially bitumen-free.
Any suitable amount of first solvent may be added to the first solvent-wet tailings in order to displace the bitumen-enriched solvent phase. In certain embodiments, the second quantity of first solvent is added to the first solvent-wet tailings in an amount of from about 10% to about 200% of the first quantity of first solvent mixed with the material comprising bitumen. The second quantity of first solvent may also be added to the first solvent-wet tailings in any suitable fashion. For example, where the first solvent-wet tailings remain loaded in the frame chamber of a plate and frame-type filter press as described above, the second quantity of first solvent may be added to the frame chamber to displace the residual bitumen-enriched solvent phase out of the first-solvent wet tailings and through the filter screens on either side of the filter chamber.
The second quantity of first solvent may be the same first solvent as used in step 100 of mixing first solvent with the material comprising bitumen. Alternatively, the second quantity of first solvent may be a different solvent from the first quantity of first solvent. However, the second quantity of first solvent is still of the type of first solvents described in greater detail above (e.g., a light aromatic solvent).
The residual bitumen-enriched solvent phase displaced from the first solvent-wet tailings includes predominantly bitumen and first solvent. In certain embodiments, the residual bitumen-enriched solvent phase includes from about 5 wt % to about 50 wt % bitumen and from about 50 wt % to about 95 wt % first solvent. Little to no non-bitumen components of the material comprising bitumen is present in the residual bitumen-enriched solvent phase. After removal of the residual bitumen-enriched solvent phase, the first solvent-wet tailings include little or no bitumen. In certain embodiments, the first solvent-wet tailings include from 0 wt % to about 2 wt % bitumen, from about 2 wt % to about 15 wt % first solvent, and from about 83 wt % to about 98 wt % non-bitumen components.
The residual bitumen-enriched solvent phase collected from the second separation stage may be combined with the bitumen-enriched solvent phase collected from the first separation stage prior to any further processing conducted on the bitumen-enriched solvent phase.
In some embodiments, the second separation stage is carried out by washing the first solvent-wet tailings with the second quantity of first solvent in a countercurrent process. The countercurrent process generally includes moving the first solvent-wet tailings in one direction while passing the second quantity of first solvent through the first solvent-wet tailings in an opposite direction. For example, the first solvent-wet tailings may be loaded at the bottom of a screw classifier conveyor positioned at an incline, while second quantity of first solvent is introduced at the top of the screw classifier conveyor. An exemplary screw classifier conveyor suitable for use in this method is described in U.S. Pat. No. 2,666,242. As the screw classifier conveyor moves the first solvent-wet tailings upwardly, the second quantity of first solvent flows down the inclined screw classifier conveyor and passes through the first solvent-wet tailings. The second quantity of first solvent displaces any residual bitumen-enriched solvent phase contained in the first solvent-wet tailings, thereby “washing” the bitumen from the first solvent-wet tailings.
Separation of the residual bitumen-enriched solvent phase and the first solvent-wet tailings naturally occurs based on the configuration of the screw classifier conveyor, with the predominantly liquid residual bitumen-enriched solvent phase collecting at one end of the washing unit and the predominantly solid first solvent-wet tailings at the opposite end of the washing unit. For example, when an inclined screw classifier conveyor is used, the residual bitumen-enriched solvent phase will collect at the bottom of the screw classifier conveyor, while the first solvent-wet tailings will collect at the top of the screw classifier conveyor. The residual bitumen-enriched solvent phase includes predominantly bitumen and first solvent. In certain embodiments, the residual bitumen-enriched solvent phase includes from about 5 wt % to about 50 wt % bitumen and from about 50 wt % to about 95 wt % first solvent. The bitumen-enriched solvent phase may include relatively minor amounts of non-bitumen components of the material comprising bitumen. The first solvent-wet tailings include predominantly first solvent and non-bitumen components of the material comprising bitumen. The first solvent component of the first solvent-wet tailings is first solvent that does not pass all the way through the first solvent-wet tailings in the countercurrent washing process. In certain embodiments, the first solvent-wet tailings includes from about 5 wt % to about 20 wt % first solvent and from about 80 wt % to about 95 wt % non-bitumen components (e.g., mineral solids). The first solvent-wet tailings may include no bitumen, especially in the case where additional quantities of first solvent are added to the first solvent-wet tailings as described in greater detail below.
The countercurrent process may include multiple stages. For example, after a first pass of first solvent through the first solvent-wet tailings, the resulting residual bitumen-enriched solvent phase may be passed through the first solvent-wet tailings several more times. Alternatively, additional quantities of fresh first solvent may be passed through the first solvent-wet tailings one or more times. In this manner, the residual bitumen-enriched solvent phase or fresh quantities of first solvent become progressively more enriched with bitumen after each stage and the first solvent-wet tailings lose progressively more bitumen after each stage.
Another suitable process for separating the bitumen-enriched solvent phase from the first solvent includes loading the first mixture in a vertical column and injecting a second quantity of first solvent into the first mixture. More specifically, the second quantity of first solvent is injected into the first material at a top end of the vertical column such that the second quantity of first solvent passes through the first material and displaces the bitumen-enriched solvent phase included in the first material. The injection of the second quantity of first solvent results in the bitumen-enriched solvent phase exiting the vertical column at the bottom end of the vertical column where it may be collected.
Any method of loading the first mixture in the vertical column may be used. First mixture may be poured into the vertical column or, when an appropriate first mixture viscosity is obtained during the mixing of the first solvent and the material comprising bitumen, the first mixture may be pumped into the vertical column. First mixture is generally loaded in the vertical column by introducing the first mixture into the column at the top end of the vertical column. The bottom end of the vertical column is blocked, such as by a removable plug or by virtue of the bottom end of the vertical column resting against the floor. In certain embodiments, a metal filter screen at the bottom end of the vertical column is used to maintain the first mixture in the vertical column. As such, introducing first mixture at the top end of the vertical column fills the vertical column with first mixture. The amount of first mixture loaded in the vertical column may be such that the first mixture substantially fills the vertical column with first mixture. In certain embodiments, first mixture is added to the vertical column to occupy 90% or more of the volume of the vertical column. In certain embodiments, the first mixture is not filled to the top of the vertical column so that room is provided to inject first solvent, second solvent, etc., into the vertical column.
The vertical orientation of the vertical column includes aligning the column substantially perpendicular to the ground, but also includes orientations where the column forms angles less than 90° with the ground. The column may generally be oriented at any angle that results in gravity aiding the flow of the first solvent, second solvent, etc., from one end of the column to the other. In certain embodiments, the column is oriented at an angle anywhere within the range of from about 1° to 90° with the ground. In a preferred embodiment, the column is oriented at an angle anywhere within the range of from about 15° to 90° with the ground.
The material of the vertical column is also not limited. Any material that will hold the first mixture within the vertical column may be used. The material is also preferably a non-porous material such that various liquids injected into the vertical column may only exit the column from one of the ends of the vertical column. The material may be a corrosive resistant material so as to withstand the potentially corrosive components of the first mixture loaded in the column as well as any potentially corrosive materials injected into the vertical column.
The shape of the vertical column is not limited to a specific configuration in all embodiments. Generally speaking, the vertical column has two ends opposite one another, designated a top end and a bottom end. The cross-section of the vertical column may be any shape, such as a circle, oval, square or the like. The cross-section of the vertical column may change along the height of the column, including both the shape and size of the vertical column cross-section. The vertical column may be a straight line vertical column having no bends or curves along the height of the vertical column. Alternatively, the vertical column may include one or more bends or curves.
Various dimensions may be used for the vertical column, including the height, inner cross sectional diameter and outer cross sectional diameter of the vertical column. In certain embodiments, the ratio of height to inner cross sectional diameter may range from 0.5:1 to 15:1.
The second quantity of first solvent may be injected into the vertical column by any suitable method. In certain embodiments, the second quantity of first solvent is poured into the vertical column at the top end and allowed to flow down through the first mixture loaded therein under the influence of gravity.
The amount of first solvent added to the first mixture is not limited. The amount is preferably enough first solvent to displace most or all of the dissolved bitumen content of the first mixture. In certain embodiments, the second quantity of first solvent added to the first mixture is from about 1.25 to about 2.25 times the amount of bitumen by volume in the original material comprising bitumen.
Upon injection into the first mixture, the first solvent flows downwardly through the height of the column via small void spaces in the first mixture. The first solvent may flow downwardly through the force of gravity or by an external force applied to the vertical column. Examples of external forces applied include the application of pressure from the top of the vertical column or the application of suction at the bottom of the vertical column.
In certain embodiments, the addition of first solvent is carried out under flooded conditions. In other words, more first solvent is added to the top of the vertical column than what flows down through the first mixture, thereby creating a head of solvent at the top of the vertical column.
In certain embodiments, the bitumen-enriched solvent exiting the vertical column includes from about 10 wt % to about 60 wt % bitumen and from about 40 wt % to about 90 wt % first solvent. Minor amounts of non-bitumen material may also be included in the bitumen-enriched solvent phase. In certain embodiments, 95% or more of the bitumen is removed from the first mixture.
Various methods of collecting the bitumen-enriched solvent may be used, such as by providing a collection vessel at the bottom end of the vertical column. The bottom end of the vertical column may include a metal filter screen having a mesh size that does not permit first mixture to pass through but which does allow for bitumen-enriched solvent to pass through and collect in a collection vessel located under the screen. Collection of bitumen-enriched solvent may be carried out for any suitable period of time. In certain embodiments, collection is carried out for 2 to 30 minutes.
After injecting a second quantity of first solvent and collecting the bitumen-enriched solvent at the bottom of the vertical column, additional quantities of first solvent may be added to the vertical column to extract additional bitumen from the first mixture. Repeating the addition of first solvent and collecting the resultant bitumen-enriched solvent phase may increase the overall extraction rate of bitumen from the first mixture. In certain embodiments, the use of multiple first solvent injection steps results in removing 99% or more of the bitumen in the first mixture.
After separating the bitumen-enriched solvent phase from the first mixture, a further step 120 may take place to crack at least a portion of the bitumen component of the bitumen-enriched solvent phase inside a nozzle reactor. Cracking of the bitumen can produce a light hydrocarbon liquid distillate.
Nozzle reactors include any type of apparatus wherein differing types of materials are injected into an interior reactor chamber of the nozzle reactor for the purpose of seeking to cause the materials to interact within the interior reactor chamber and achieve alteration of the mechanical or chemical composition of one or more of the materials. In the instant embodiment, the bitumen-enriched solvent phase is injected into the interior reactor chamber of the nozzle reactor along with a cracking material, wherein the two materials interact to crack the bitumen component of the bitumen-enriched solvent phase and produce lighter hydrocarbon material.
Various types of nozzle reactor suitable for cracking hydrocarbons such as bitumen may be used. In certain embodiments, the nozzle reactor is a nozzle reactor as disclosed in co-pending U.S. application Ser. No. 11/233,385, hereby incorporated by reference in its entirety. The nozzle reactor of U.S. application Ser. No. 11/233,385 may generally include an interior reactor chamber, an injection passage, and a material feed passage. The interior reactor chamber includes an injection end and an ejection end. The injection passage is mounted in the nozzle reactor in material injecting communication with the injection end of the interior reactor chamber. The injection passage has an enlarged volume injection section, an enlarged volume ejection section, and a reduced volume mid-section intermediate the enlarged volume injection section and enlarged volume ejection section. The injection passage also has a material injection end and a material ejection end, with the material ejection end being in injecting communication with the interior reactor chamber. The material feed passage penetrates the interior reactor chamber and is generally located adjacent to the material ejection end of the injection passage. Additionally, the material feed passage is aligned so as to be transverse to the axis of the injection passage axis extending from the material injection end to the material ejection end in the injection passage.
FIG. 2 illustrates a nozzle reactor disclosed in U.S. application Ser. No. 11/233,385 that is suitable for use in this embodiment. The nozzle reactor, indicated generally at 10, has a reactor body injection end 12, a reactor body 14 extending from the reactor body injection end 12, and an ejection port 13 in the reactor body 14 opposite its injection end 12. The reactor body injection end 12 includes an injection passage 15 extending into the interior reactor chamber 16 of the reactor body 14. The central axis A of the injection passage 15 is coaxial with the central axis B of the interior reactor chamber 16.
The injection passage 15 has a circular diametric cross-section and, as shown in the axially-extending cross-sectional view of FIG. 2, opposing inwardly curved side wall portions 17, 19 (i.e., curved inwardly toward the central axis A of the injection passage 15) extending along the axial length of the injection passage 15. In certain embodiments, the axially inwardly curved side wall portions 17, 19 of the injection passage 15 allow for a higher speed of injection gas when passing through the injection passage 15 into the interior reactor chamber 16.
The side wall of the injection passage 15 can provide one or more among: (i) uniform axial acceleration of cracking material passing through the injection passage; (ii) minimal radial acceleration of such material; (iii) a smooth finish; (iv) absence of sharp edges; and (v) absence of sudden or sharp changes in direction. The side wall configuration can render the injection passage 15 substantially isentropic.
A material feed passage 18 extends from the exterior of the reactor body 14 toward the interior reaction chamber 16 transversely to the axis B of the interior reactor chamber 16. The material feed passage 18 penetrates an annular material feed port 20 adjacent the interior reactor chamber wall 22 at the interior reactor chamber injection end 24 abutting the reactor body injection end 12. The material feed port 20 includes an annular, radially extending reactor chamber feed slot 26 in material-injecting communication with the interior reactor chamber 16. The material feed port 20 is thus configured to inject feed material: (i) at about a 90° angle to the axis of travel of cracking material injected from the injection passage 15; (ii) around the entire circumference of a cracking material injected through the injection passage 15; and (iii) to impact the entire circumference of the free cracking material stream virtually immediately upon its emission from the injection passage 15 into the interior reactor chamber 16.
The annular material feed port 20 may have a U-shaped or C-shaped cross-section among others. In certain embodiments, the annular material feed port 20 may be open to the interior reactor chamber 16, with no arms or barrier in the path of fluid flow from the material feed passage 18 toward the interior reactor chamber 16. The junction of the annular material feed port 20 and material feed passage 18 can have a radiused cross-section.
The interior reactor chamber 16 can be bounded by stepped, telescoping side walls 28, 30, 32 extending along the axial length of the reactor body 14. In certain embodiments, the stepped side walls 28, 30, 32 are configured to: (i) allow a free jet of injected cracking material, such as superheated steam, natural gas, carbon dioxide, or other gas, to travel generally along and within the conical jet path C generated by the injection passage 15 along the axis B of the interior reactor chamber 16, while (ii) reducing the size or involvement of back flow areas, e.g., 34, 36, outside the conical or expanding jet path C, thereby forcing increased contact between the high speed cracking material jet stream within the conical jet path C and feed material, such as heavy hydrocarbons, injected through the annular material feed port 20.
As indicated by the drawing gaps 38, 40 in the embodiment of FIG. 2, the reactor body 14 has an axial length (along axis B) that is much greater than its width. In the FIG. 2 embodiment, exemplary length-to-width ratios are typically in the range of 2 to 7 or more.
The dimensions of the various components of the nozzle reactor shown in FIG. 2 are not limited, and may generally be adjusted based on the amount of material feed to be cracked inside the nozzle reactor. Table 1 provides exemplary dimensions for the various components of the nozzle reactor based on the hydrocarbon input in barrels per day (BPD).

	TABLE 1

	Material Feed Input (BPD)

Nozzle Reactor Component (mm)	5,000	10,000	20,000

Injection Passage, Enlarged Volume	148	207	295
Injection Section Diameter
Injection Passage, Reduced Volume	50	70	101
Mid-Section Diameter
Injection Passage, Enlarged Volume	105	147	210
Ejection Section Diameter
Injection Passage Length	600	840	1,200
Interior Reactor Chamber Injection	187	262	375
End Diameter
Interior Reactor Chamber Ejection	1,231	1,435	1,821
End Diameter
Interior Reactor Chamber Length	6,400	7,160	8,800
Overall Nozzle Reactor Length	7,000	8,000	10,000
Overall Nozzle Reactor Outside	1,300	1,600	2,000
Diameter
Overall Nozzle Reactor Length to	5.4	5.0	5.0
Outside Diameter Ratio

As used in the method of this embodiment, the nozzle reactor is generally operated by injecting bitumen-enriched solvent phase into the interior reactor chamber 16 via the material feed passage 18. At least a portion of the bitumen-enriched solvent phase, including at least a portion of the bitumen component, is injected into the reactor body passage 16 is in a liquid phase. The bitumen-enriched solvent phase may be pretreated prior to injection into the interior reactor chamber 16 in order to alter the amount or fraction of bitumen-enriched solvent phase that is in a liquid phase. In certain embodiments, the temperature and/or pressure of the bitumen-enriched solvent phase is adjusted to alter the amount of bitumen-enriched solvent phase in the liquid phase prior to injection. The non-liquid portion of the bitumen-enriched solvent phase is typically injected into the interior reactor chamber 16 in a gaseous phase.
As the bitumen-enriched solvent phase is injected into the interior reactor chamber 16, a cracking material is injected into the interior reactor chamber 16 by way of the injection passage 15. The configuration of the injection passage 15 is such that the cracking material is accelerated to a supersonic speed and enters the interior reactor chamber 16 at supersonic speed. Shock waves are produced by the cracking material traveling at supersonic speeds, and the shock waves crack the largest hydrocarbon molecules present in the bitumen component of the bitumen-enriched solvent phase entering the interior reactor chamber 16 via the material feed passage 18. In this manner, bitumen may be broken down into lighter hydrocarbon molecules.
In certain embodiments, about 10% to about 95% of the bitumen injected into the interior reactor chamber 16 is cracked and broken down into lighter hydrocarbon products. The cracking of bitumen produces hydrocarbons having lower molecular weight than the bitumen. In certain embodiments, the bitumen is broken down into light hydrocarbon liquid distillate. The light hydrocarbon liquid distillate includes hydrocarbons having a molecular weight less than about 300 Daltons. In certain embodiments, about 30% to about 60% of the bitumen cracked inside the interior reactor chamber 16 is cracked into light hydrocarbon liquid distillate.
Other portions of the bitumen-enriched solvent phase (e.g., lower molecular weight molecules) injected into the interior reactor chamber 16 may pass through the nozzle reactor without being cracked. Often, some fraction of the bitumen-enriched solvent phase that is injected into the interior reactor chamber 16 may pass through the nozzle reactor uncracked because of kinetic limitations. These portions of the bitumen-enriched solvent phase may be referred to as non-participating hydrocarbon, since the shock waves produced by the injection of the cracking material through the injection passage 15 do not act on this material to crack it into lighter hydrocarbon material. Bitumen that is cracked but not cracked into light hydrocarbon distillate may also be referred to as non-participating hydrocarbon. In certain embodiments, about 40% to about 70% of the bitumen injected into the interior reactor chamber 16 is not cracked and exits the nozzle reactor as non-participating hydrocarbon.
In certain embodiments, the light hydrocarbon distillate and the non-participating hydrocarbon exiting the nozzle reactor may be transported to a separation unit that separates the hydrocarbon distillate from the non-participating hydrocarbon. The separation unit may be any suitable separator capable of separating the two streams. Examples of suitable separation units include, but are not limited to, distillation units, vacuum towers, gravity separation units, filtration units, and cyclonic separation units.
In certain embodiments, the non-participating hydrocarbon stream that exits the nozzle reactor and is separated from the light hydrocarbon distillate may be subjected to further processing to upgrade the non-participating hydrocarbon into useful material. Various types of processing may be performed on the non-participating hydrocarbon for upgrading the non-participating hydrocarbon. In one example, the non-participating hydrocarbon is injected into a second nozzle reactor or recycled back into the first nozzle reactor. Where the non-participating hydrocarbon is injected into a second nozzle reactor, the structure of the second nozzle reactor may be similar or identical to the first nozzle reactor described in greater detail above. The dimensions of the second nozzle reactor may be identical to the dimensions of the first nozzle reactor, or the dimensions of the second nozzle reactor may be scaled up or down from the dimensions of the first nozzle reactor. The non-participating hydrocarbon stream may also be pretreated prior to injecting the hydrocarbon stream into the second nozzle reactor in order to alter the amount of non-participating hydrocarbon entering the second nozzle reactor in the liquid phase. Such further treatment of non-participating hydrocarbon is discussed in greater detail in co-pending U.S. application Ser. No. 12/466,923.
Not all of the bitumen component of the bitumen-enriched solvent phase need be cracked in a nozzle reactor to produce light hydrocarbon distillate. A portion of the bitumen may be upgraded. Upgrading of the bitumen may comprise any processing that generally produces a stable liquid (i.e., synthetic crude oil) and any subsequent refinement of synthetic crude oil into petroleum products. The process of upgrading bitumen to synthetic crude oil may include any processes known to those of ordinary skill in the art, such as heating or cracking the bitumen to produce synthetic crude. The process of refining synthetic crude may also include any processes known to those of ordinary skill in the art, such as distillation, hydrocracking, hydrotreating and coking. They petroleum products produced by the upgrading process are not limited, any may include petroleum, diesel fuel, asphalt base, heating oil, kerosene, and liquefied petroleum gas.
Referring back to FIG. 1, step 130 includes mixing the light hydrocarbon distillate produced in the first nozzle reactor with a further quantity of material comprising bitumen. The light hydrocarbon distillate may act as a solvent capable of dissolving bitumen, and therefore can be used in the first mixing step 100 described above. In certain embodiments, the light hydrocarbon distillate can supplement or eliminate the first solvent used to dissolve bitumen in the first step of the method of this embodiment to thereby reduce or eliminate the need for obtaining first solvent from a third party when carrying out a solvent extraction step on the material comprising bitumen.
The manner in which the light hydrocarbon is mixed with a further quantity of material comprising bitumen may be similar or identical to any of the manners of mixing described above with respect to step 100 and the mixing of the first solvent with the first quantity of material comprising bitumen.
Although not depicted in FIG. 1, the method of this embodiment may include further steps for processing the first solvent-wet tailings to remove the first solvent from the tailings. As noted above, the first solvent-wet tailings may include from about 5 wt % to about 25 wt % of the first solvent Removing the first solvent from the tailings may produce a more environmentally friendly tailings product.
Accordingly, the method may further include a step of separating the first solvent component of the first solvent-wet tailings from the first solvent-wet tailings by adding a second solvent to the first solvent-wet tailings. Removal of the first solvent with a second solvent displaces the first solvent from the first solvent-wet tailings. Some second solvent added to the first solvent-wet tailings may remain therein, which results in the first solvent-wet tailings becoming second solvent-wet tailings. The second solvent component of the second solvent-wet tailings may be also be removed to thereby produce solvent-free tailings.
The second solvent can be any suitable solvent that is useful for displacing the first solvent. In certain embodiments the second solvent has a lower vapor pressure than the first solvent to enhance removal of the second solvent in subsequent processing steps. In certain embodiments, the second solvent may be a hydrocarbon solvent. Any suitable hydrocarbon solvent or mixture of hydrocarbon solvents that is capable of displacing the first solvent may be used. The hydrocarbon solvent or mixture of hydrocarbon solvents can be economical and relatively easy to handle and store. The hydrocarbon solvent or mixture of hydrocarbon solvents may also be generally compatible with refinery operations.
In certain embodiments, the second hydrocarbon solvent can include one or more volatile hydrocarbon solvents. Volatile hydrocarbon solvents generally include hydrocarbons having a boiling point temperature between about −20° C. and 150° C. Volatile hydrocarbon solvents may also include aliphatic compounds that are capable of solvating bitumen and/or the first solvent. These aliphatic compounds can include compounds such as branched or unbranched alkanes or alkenes. Any of these aliphatic compounds can be functionalized or non-functionalized. In certain embodiments, the second solvent includes one or more aliphatic hydrocarbons having 3 to 9 carbon atoms. In some embodiments, the second solvent includes aliphatic hydrocarbons having no more than 9 carbon atoms. The second solvent may also include lower carbon paraffins, such as cyclo- and iso-paraffins having 3 to 9 carbon atoms. The second solvent may include one or more of any of the following compounds: methane, ethane, propane, butane, and/or pentane, alkene equivalents of these compounds and/or combinations and derivatives thereof.
In certain embodiments, the second solvent includes liquefied petroleum gas (LPG). The term “liquefied petroleum gas” is used broadly herein to refer to any hydrocarbon gas (hydrocarbons that are gases at ambient temperature (25° C.) and pressure (1 atm) and has been compressed to form a liquid. Preferably, the LPG is primarily or even entirely propane or predominantly or entirely butane. However, other LPG formulations are contemplated including commercially available formulations. The composition of common commercial LPG can vary depending on the time of the year, geographical location, etc. Commercial LPG is a natural derivative of both natural gas and crude oil. Often, LPG is a mixture of propane and butane (n-butane and/or i-butane) with small amounts of propylene and butylene (any one or combination of the four isomers). A powerful odorant such as ethanethiol is typically added to make it easy to detect leaks. Commercial LPG also often contains very small amounts of lighter hydrocarbons, such as ethane and ethylene, and heavier hydrocarbons such as pentane.
Three examples of commercial LPG are shown below in Table 2.

TABLE 2

Examples of Commercially Available LPG

		Commercial	Commercial Butane/
Component	HD-5 Propane	Propane	Propane Mixture

Lighter	Min 90 v-% propane	Mixture of propane	Mixture of butane
Hydrocarbons	Max v-5% propylene	and/or propylene	and/or butylenes
			and propane and/or
			propylenes

Butane and	2.5	v-%	2.5	v-%	—
heavier
hydrocarbons

Pentane and	—	—	Max v-2%
heavier
hydrocarbons

Residual matter	0.05	ml	0.05	ml	—
Total Sulfur	123	w-PPM	185	w-PPM	140 w-PPM

LPG is stored and transported under pressure to maintain the hydrocarbons as liquids. In certain embodiments, LPG has a boiling point at atmospheric pressure of approximately −80° C. to 10° C., desirably, approximately −55° C. to 5° C., or, suitably, approximately −35° C. to −5° C.
Adding second solvent to the first solvent-wet tailings may be carried out in any suitable manner that results in first solvent displacement from the first solvent-wet tailings. In certain embodiments, second solvent may be added to the first solvent-wet tailings in a similar or identical manner to the addition of first solvent to the first solvent-wet tailings described in greater detail above. In certain embodiments, the second solvent is added to the first solvent-wet tailings without overly agitating the first solvent-wet tailings in order to avoid the formation of water-solvent emulsions as discussed in greater detail above.
The amount of the second solvent added to the first solvent-wet tailings is sufficient to effectively displace at least a portion, or desirably all, of the first solvent in the first solvent-wet tailings. The amount of second solvent added to the first solvent-wet tailings is approximately 0.5 to 1 times the amount of bitumen by volume originally contained in the material comprising bitumen.
In certain embodiments, the addition of second solvent to the first solvent-wet tailings results in the removal of 95% or more of the first solvent in the first solvent-wet tailings. The first solvent may leave the first solvent-wet tailings as a first solvent-second solvent mixture. The first solvent-second solvent mixture may include from about 5 wt % to about 50 wt % first solvent and from about 50 wt % to about 95 wt % second solvent. The removal of the first solvent from the first solvent-wet tailings through the addition of second solvent may result in a quantity of second solvent not passing all the way through the first solvent-wet tailings. Consequently, the first solvent-wet tailings become a second solvent-wet tailings upon separation of the first solvent. In certain embodiments, the second solvent-wet tailings include from about 70 wt % to about 95 wt % non-bitumen components and from about 5 wt % to about 30 wt % second solvent.
As with previously described separation steps, separation of the first solvent from the first solvent-wet tailings by adding second solvent may be preceded or followed by applying pressurized gas over the first solvent-wet tailings. Applying a pressurized gas over the first solvent-wet tailings facilitates the separation of the first solvent component of the first solvent-wet tailings from the non-bitumen components of the first solvent-wet tailings. The liberated first solvent can then be displaced from the first solvent-wet tailings by applying additional second solvent to the first solvent-wet tailings. Applying a pressurized gas over the first mixture may also provide a driving force for moving bitumen-enriched solvent phase out of the first mixture without the need for adding additional first solvent. Any suitable gas may be used. In certain embodiments, the gas is nitrogen, carbon dioxide or steam. The gas may also be added over the second mixture in any suitable amount. In certain embodiments, 62.5 ft³to 375 ft³of gas per ton of material comprising bitumen is used. This is equivalent to a range of about 4.5 liters to 27 liters of gas per liter of material comprising bitumen. In some embodiments, 125 ft³of gas per ton of material comprising bitumen is used.
In certain embodiments, separation of the first solvent from the first solvent-wet tailings utilizes a plate and frame-type filter press. The plate and frame-type filter press may be a separate plate and frame-type filter press from the plate and frame-type filter press used to separate the bitumen-enriched solvent phase from the first mixture and/or the first solvent-wet tailings, or the same plate and frame-type filter press may be used to separate the bitumen-enriched solvent phase from the first mixture (or first solvent-wet tailings) and to separate the first solvent from the first solvent-wet tailings. When the same plate and frame-type filter press is used, the method may include adding second solvent to the first solvent-wet tailings still contained in the frame chamber. In other words, the method need not necessarily always include a step of removing the first solvent-wet tailings from the plate and frame-type filter press before mixing with second solvent. The second solvent may be pumped into the plate and frame-type filter press where it displaces the first solvent component of the first solvent-wet tailings located in the frame chambers.
When utilizing a plate and frame-type filter press to separate the first solvent from the first solvent-wet tailings, pressurized gas may be injected into the frame chamber after the frame chamber has been filled with the first solvent-wet tailings. In certain embodiments, injecting pressurized gas into the first solvent-wet tailings can promote the separation of the first solvent from mineral solids in the first solvent-wet tailings. The process for adding gas can be similar or identical to the method described above with respect to separation of the bitumen-enriched solvent phase from the first mixture (or first solvent-wet tailings) in a plate and frame-type filter press.
The second solvent passes through the first solvent-wet tailings loaded in the frame chamber and displaces the first solvent. In certain embodiments, 95% or more of the first solvent in the first solvent-wet tailings is displaced by the second solvent. This first solvent passes through the filter clothes and out of the frame chamber. Some of the second solvent can also pass through the filter clothes, while some second solvent can remain in the frame chamber. Consequently, the first solvent-wet tailings become second solvent-wet tailings.
The separation of first solvent from the first solvent-wet tailings through the addition of second solvent may also be carried out as a countercurrent washing process. The countercurrent process generally includes moving the first solvent-wet tailings in one direction while passing the second solvent through the first solvent-wet tailings in an opposite direction. For example, the first solvent-wet tailings may be loaded at the bottom of a screw classifier conveyor positioned at an incline, while second solvent is introduced at the top of the inclined screw classifier conveyor. As the screw classifier conveyor moves the first solvent-wet tailings upwardly, the second solvent flows down the inclined screw classifier conveyor and passes through the first solvent-wet tailings. The two materials mix and first solvent is displaced by the second solvent, thereby “washing” the first solvent from the first solvent-wet tailings. In certain embodiments, 85% or more of the first solvent in the first solvent-wet tailings is displaced by the second solvent. The first solvent-second solvent mixture that collects at one end of the screw classifier conveyor may include from about 5 wt % to about 50 wt % first solvent and from about 50 wt % to about 95 wt % second solvent. Some of the second solvent may remain with the tailings, thereby forming the second solvent-wet tailings that collect at the opposite end of the screw classifier conveyor. In certain embodiments, the second solvent-wet tailings includes from about 10 wt % to about 30 wt % second solvent and from about 70 wt % to about 90 wt % non-bitumen components.
The countercurrent process may include multiple stages as described in greater detail above with respect to washing the first mixture or first solvent-wet tailings. In a multiple stage countercurrent process, the second solvent can displace progressively more first solvent after each stage and the first solvent-wet tailings lose progressively more first solvent after each stage.
When separation of the bitumen-enriched solvent phase from the first mixture is carried out using a vertical column as described in greater detail above, the first solvent component included in the first solvent-wet tailings loaded in the vertical column may be separated, at least to some degree, from the first solvent-wet tailings by injecting the second solvent at the top end of the vertical column. In this manner, second solvent may flow down through the vertical column and displace the first solvent contained in the first solvent-wet tailings loaded in the vertical column. A mixture of first solvent and second solvent may be collected at the bottom end of the vertical column, while some second solvent may remain in the vertical column, leading the first solvent-wet tailings to become second solvent-wet tailings.
The second solvent may be injected into the vertical column by any suitable method. In certain embodiments, the first quantity of second solvent is poured into the vertical column at the top end and allowed to flow down through the first mixture loaded therein. The downward flow of the second solvent can be allowed to progress under the force of gravity or external forces may be applied, such as pressure at the top of the vertical column or suction at the bottom of the vertical column.
The amount of second solvent added can vary. In some embodiments, the amount is preferably enough second solvent to displace most or all of the first solvent contained in the first solvent-wet tailings loaded in the vertical column. In certain embodiments, the first quantity of second solvent added to the first mixture is from about 0.5 to about 2.0, and preferably about 1 times the amount of bitumen by volume contained in the original material comprising bitumen. If multiple second solvent addition steps are performed, then the total amount of second solvent added is about 1.0 times the amount of bitumen by volume contained in the original material comprising bitumen.
The mixture of first solvent and second solvent that flows downwardly through the height of the column may exit the bottom end of the vertical column where it may be collected for further use and processing. In certain embodiments, the mixture of first solvent and second solvent includes from about 50 wt % to about 90 wt % second solvent and from about 10 wt % to about 50 wt % first solvent. Minor amounts of bitumen and non-bitumen material may also be included in the mixture of first solvent and second solvent.
In certain embodiments, the addition of second solvent is carried out under flooded conditions. In other words, more second solvent is added to the top of the vertical column than what flows down through the first mixture, thereby creating a head of solvent at the top of the vertical column.
Various methods of collecting the mixture of first solvent and second solvent may be used, such as by providing a collection vessel at the bottom end of the vertical column. The bottom end of the vertical column may include a metal filter screen having a mesh size that does not permit the tailings to pass through but which does allow for the mixture of first solvent and second solvent to pass through and collect in a collection vessel located under the screen. Collection of the mixture of first solvent and second solvent may be carried out for any suitable period of time. In certain embodiments, collection is carried out for 2 to 30 minutes.
Additional quantities of second solvent can be added to the vertical column to increase the removal of first solvent. In other words, after injecting a first quantity of second solvent and collecting the mixture of first solvent and second solvent at the bottom of the vertical column, additional quantities of second solvent may be added to the vertical column to displace additional first solvent from the tailings loaded in the vertical column. In certain embodiments, the use of multiple second solvent injection steps may result in removing 99% or more of the first solvent in the first solvent-wet tailings.
Once the second solvent-wet tailings are obtained, the second solvent component of the second solvent-wet tailings may be removed from the second solvent-wet tailings to thereby produce a more environmentally friendly tailings product. Various manners of removing second solvent from the second solvent-wet tailings may be used. In certain embodiments, the second solvent can be removed from the second solvent-wet tailings by flashing or heating the second solvent-wet tailings. In this manner, second solvent evaporates from the second solvent-wet tailings and leaves behind solvent-dry, stackable tailings. In some embodiments, pre-heated gas, such as nitrogen, may be injected into the second solvent-wet tailings to remove the second solvent. The pre-heated gas may be at a temperature above the boiling point temperature of the second solvent. Separation of the second solvent from the second solvent-wet tailings may result in 95% or more of the second solvent in the second solvent-wet tailings being removed.
When the second solvent is a volatile hydrocarbon, the energy required to remove the second solvent may be minimal. In certain embodiments, the second solvent may be removed from the second solvent-wet tailings at room temperature. Separation of the second solvent at room temperature or any temperature under the boiling point temperature of water is also useful for avoiding the removal of water from the tailings.
Separating second solvent from the second solvent-wet tailings may also include separation of any first solvent included in the second solvent-wet tailings. Separation of the first solvent may occur together with the separation of the second solvent, such as by heating or flashing the second-solvent wet tailings in a manner causing both solvents to evaporate from the second-solvent wet tailings. Alternatively, the separation may be incremental, wherein the flashing or heating is carried out to start with at conditions that will cause only the second solvent to evaporate, followed by adjusting the conditions to cause the evaporation of the first solvents. The first and second solvents separated from the second solvent-wet tailings may be recovered and recycled within the method.
The solvent-dry, stackable tailings resulting from removal of the second solvent from the second solvent-wet tailings may generally include inorganic solids, such as sand and clay, water, and little to no first and second solvent. As used herein, the term “solvent-dry” means containing less than 0.1 wt % total solvent. As used herein, the term “stackable” means having a water content of from about 2 wt % to about 15 wt %. This range of water content creates a damp tailings that will not produce significant amounts of dust when transporting or depositing the tailings. This range of water content may also provide stackable tailings that will not flow like dry sand, and therefore have the ability to be retained within an area without the need for retaining structures (e.g., a tailings pond). This range of water content also provides tailings that are not so wet as to be sludge-like or liquid-like. The solvent-dry, stackable tailings produced by the above described method may also include less than 2 wt % bitumen and asphaltene.
In another variation of the above described method, the bitumen-enriched solvent phase may be separated into a bitumen component and a first solvent phase prior to cracking the bitumen component inside the first nozzle reactor to produce light hydrocarbon distillate. In certain embodiments, 90% or more of the first solvent in the bitumen-enriched first solvent phase may be separated from the bitumen-enriched solvent phase to produce a bitumen component.
Separation of the bitumen and the first solvent may be by any suitable separation method that is capable of separating the first solvent from the bitumen component. In certain embodiments, separation may be achieved by heating the bitumen-enriched solvent phase and separating first solvent from bitumen based on the boiling point temperature of the first solvent. The heat can be provided by any suitable heating source, such as by a heat exchanger. Heating can be done substantially at ambient pressure, at a pressure less than ambient, or at a pressure greater than ambient. In certain embodiments, the separation of the first solvent and the bitumen is accomplished by a distillation tower.
Table 3 shows the boiling points of some of the components that may be used as or included in the first solvent. In certain embodiments, the bitumen-enriched solvent phase may be heated to a temperature of approximately 70° C. to 350° C., such as approximately 100° C. to 350° C., approximately 125° C. to 250° C., or, desirably, approximately 140° C. to 220° C.

TABLE 3

Solvent Boiling Points

		Boiling
	Compound	Point ° C.

	Fatty Acid Methyl Esters
	C8	187
	C10	224
	C12	262
	C14	295
	C16	338
	C18	352
	Aromatic Hydrocarbons
	Toluene	111
	Xylene	140
	Coal Tar Naphtha	150-220
	Petroleum Naphtha	172-215
	Light distillate	140-260
	Middle distillate	200-400
	Aromatic/Solvesso 100	160-170
	Aromatic/Solvesso 150	185-205
	Aromatic/Solvesso 200	240-275

In some embodiments, separation may be accomplished by utilizing a multi-hearth solvent recovery furnace. Multi-hearth solvent recovery furnaces typically include alternating arrangements of centrally located hearths and peripherally located hearths. The hearths can be heated, for example, with oil fired muffles and/or high pressure steam coils. In some embodiments, hearths near the top of the furnace may be heated to higher temperatures than hearths closer to the bottom of the furnace.
In certain embodiments, the bitumen-enriched solvent phase may be routed to a separator to recover the first solvent. The separator may separate the first solvent from bitumen product. The separator may also be configured to separate any water and mineral solids that might be present in bitumen-enriched solvent phase. Separation of the bitumen-enriched solvent phase may also be configured to function despite the presence of fine solid material. For example, a separator used to separate the first solvent from the bitumen can include a suitable packing material, such as vertical slats, to provide increased surface area for condensation and evaporation. This packing material can be resistant to clogging by the fine solid material. In those embodiments where the separation is accomplished by utilizing a distillation tower, the fine solid materials may fall to the bottom and be cleaned out periodically.
Just as with previous separation and mixing steps, separation of first solvent from bitumen can be performed as a continuous, batch, or semi-batch process. Continuous processing is typically used in larger scale implementations. However, batch processing may result in more complete separations than continuous processing.
Once the first solvent is separated from the bitumen, the first solvent may be recycled for further use in the same process or collected for use in other processes. When recycled for use in the same process, the first solvent may be transported back to, for example, a first vessel used to mix the material comprising bitumen and the first solvent. The recycled first solvent may be used to supplement or replace a fresh source of first solvent used in the first mixing step. The recycled first solvent may also be used with the light hydrocarbon liquid distillate to eliminate the need for fresh first solvent in the first solvent extraction stage. In other words, rather than using first solvent obtained from a third party to carry out the first solvent extraction stage, the light hydrocarbon liquid distillate may supplement the recycled first solvent to whatever extent necessary in order to provide a sufficient amount of first solvent for solvent extracting bitumen from additional quantities of material comprising bitumen.
In some embodiments, the method may include extracting bitumen from a bitumen comprising material, deasphalting the extracted bitumen to produce asphaltenes, cracking the asphaltenes inside a nozzle reactor to form light hydrocarbon distillate, and using the light hydrocarbon distillate to extract bitumen from further material comprising bitumen.
As shown in FIG. 3, the method can generally include a first step 300 of mixing a first quantity of material comprising bitumen with a first solvent to form a first mixture, a step 310 of separating the first mixture into a bitumen-enriched solvent phase and a first solvent-wet tailings, a step 320 of separating the bitumen-enriched solvent phase into a first bitumen component and a first solvent stream, a step 330 of deasphalting the first bitumen component to form an asphaltene stream and a first hydrocarbon stream, a step 340 of cracking the asphaltene stream inside a first nozzle reactor to form a light hydrocarbon distillate and a non-participating hydrocarbon stream, and a step 350 of mixing the light hydrocarbon distillate with a second quantity of material comprising bitumen.
First steps 300 and 310 may be essentially identical to steps 100 and 110 described in greater detail above. A first solvent as described above may be mixed with a material comprising bitumen as described above to dissolve the bitumen in the material comprising bitumen. A first mixture formed by mixing the first solvent and the material comprising bitumen may be separated into a bitumen-enriched solvent phase as described above and a first solvent-wet tailings as described above. Steps 300 and 310 may be repeated one or more times to extract additional bitumen from the first solvent-wet tailings.
In step 320, the bitumen-enriched solvent phase can be separated into a bitumen component and a first solvent stream. Various manners of separating the first solvent from the bitumen may be used. In certain embodiments, 90% or more of the first solvent in the bitumen-enriched first solvent phase may be separated from the bitumen-enriched solvent phase to produce a bitumen component.
Separation of the bitumen and the first solvent may be by any suitable separation method that is capable of separating the first solvent from the bitumen component. In certain embodiments, separation may be achieved by heating the bitumen-enriched solvent phase and separating first solvent from bitumen based on the boiling point temperature of the first solvent. The heat can be provided by any suitable heating source, such as by a heat exchanger. Heating can be done substantially at ambient pressure, at a pressure less than ambient, or at a pressure greater than ambient. In certain embodiments, the separation of the first solvent and the bitumen may be accomplished by a distillation tower.
In some embodiments, separation may be accomplished by utilizing a multi-hearth solvent recovery furnace. Multi-hearth solvent recovery furnaces typically include alternating arrangements of centrally located hearths and peripherally located hearths. The hearths can be heated, for example, with oil fired muffles and/or high pressure steam coils. In some embodiments, hearths near the top of the furnace are heated to higher temperatures than hearths closer to the bottom of the furnace.
In certain embodiments, the bitumen-enriched solvent phase may be routed to a separator to recover the first solvent. The separator may separate the first solvent from bitumen product. The separator may also be configured to separate any water and mineral solids that might be present in bitumen-enriched solvent phase. Separation of the bitumen-enriched solvent phase may also be configured to function despite the presence of fine solid material. For example, a separator used to separate the first solvent from the bitumen can include a suitable packing material, such as vertical slats, to provide increased surface area for condensation and evaporation. This packing material can be resistant to clogging by the fine solid material. In those embodiments where the separation is accomplished by utilizing a distillation tower, the fine solid materials may fall to the bottom and be cleaned out periodically.
The cut temperature of the separator may affect the amount of new first solvent present in the separated first solvent. For example, at a cut temperature of 225° C., an additional 4.8 vol % of first solvent may be present in the separated first solvent as new solvent. This additional first solvent may be blended back with the bitumen product produced by the separator in order to lower the viscosity and make the bitumen product more pipelineable.
As described above, first solvent removed from the bitumen-enriched solvent phase may be recycled for further use in the same process or collected for use in other processes. When recycled for use in the same process, the first solvent may be transported back to, for example, a first vessel used to mix the material comprising bitumen and the first solvent. The recovered first solvent may be used to supplement or eliminate a fresh feed of first solvent. The recovered first solvent may also be used to supplement first light hydrocarbon distillate produced in the nozzle reactor and recycled back to the first solvent extraction step.
In step 330, the bitumen obtained from separating the bitumen-enriched first solvent phase as described above can be deasphalted to produce an asphaltene stream. Deasphalting may be accomplished by any suitable manner for deasphalting bitumen. Examples of suitable deasphalting processes include, but are not limited to, the Residuum Oil Supercritical Extraction (ROSE™) process, ambient pressure solvent deasphalting (SDA), and propane deasphalting (PDA).
The type and amount of asphaltene produced by the deasphalting step may depend on both the solvent used to perform the deasphalting process and the source of the bitumen material be deasphalted. Bitumen generally includes multiple types of asphaltene. Each type of asphaltene may be classified by the alkane solvent in which the asphaltene is insoluble. For example, a bitumen sample may include a propane-insoluble asphaltene fraction, a butane-insoluble asphaltene fraction, a pentane-insoluble asphaltene fraction, and so on. Table 4 below presents the asphaltene content of Athabasca bitumen based on various alkane solvents used to precipitate the asphaltene.

	TABLE 4

		Asphaltene Precipitated
	Solvent	from Athabasca Bitumen (wt %)

	Propane	48
	Butane	28
	Pentane	18
	Hexane	14
	Heptane	11
	Octane	9.8
	Nonane	9.4
	Decane	9.0

However, it should be noted that while Table 4 indicates that the pentane-insoluble asphaltene content of Athabasca bitumen is 18 wt %, the amount of pentane-insoluble asphaltene content of bitumen may range from about 10 wt % to about 50 wt % of the bitumen based on the source of bitumen. Once a solvent has been selected for precipitating a particular asphaltene fraction, the deasphalting step may generally recover from about 25% to 100% of the content of that asphaltene fraction in the bitumen component.
Deasphalting may produce an asphaltene product and a hydrocarbon product that includes primarily the remaining hydrocarbon fractions of the bitumen. The remaining hydrocarbons may generally include hydrocarbons having a molecular weight less than about 300 Daltons. The hydrocarbons may also be essentially asphaltene-free In many cases, certain fractions of the remaining hydrocarbons may be processed further by refinery processing to produce various commercial products, such as gasoline, naptha, kerosene and diesel oil.
In step 330, the asphaltene stream produced from the deasphalting step 320 may be used to form a light hydrocarbon liquid distillate by cracking the asphaltene stream inside a nozzle reactor. In this regard, step 330 may be similar or identical to step 120 described in greater detail above. The nozzle reactor may be similar or identical to the nozzle reactor described above. A cracking material may be injected into an interior reactor chamber while simultaneously injecting the asphaltene stream into the interior reactor chamber via the material feed passage. The asphaltene stream may enter the interior reactor chamber at a direction transverse to the direction the cracking material is injected into the interior reactor chamber. Shock waves produced by the cracking material may result in the cracking of the asphaltene material into light hydrocarbon liquid distillate having a molecular weight less than 300 Daltons. Asphaltene material not cracked inside the nozzle reactor may be considered non-participating hydrocarbon material and may be routed to a second nozzle reactor for further cracking.
In certain embodiments, the aspahltene stream injected into the first nozzle reactor may not be pure asphaltene. Rather, the asphaltene stream may also include resins and other heavy hydrocarbons. When such an asphaltene stream is injected into the nozzle reactor under certain operating conditions, the asphaltenes may be in a liquid phase while the resins and other heavy hydrocarbons may be in a gaseous state. Accordingly, the resins and hydrocarbons may pass through the nozzle reactor uncracked, while the shock waves produced inside the nozzle reactor will crack the asphaltenes into the light hydrocarbon liquid distillate. If shock waves miss some of the asphaltenes injected into the nozzle reactor or only partially crack some of the asphaltenes injected into the nozzle reactor during the short time that the asphaltenes are inside the nozzle reactor, then these asphaltenes may also pass through the nozzle reactor uncracked or not fully cracked and become part of the non-participating hydrocarbon stream.
A typical composition of the light hydrocarbon liquid distillate produced by step 340 is summarized in Table 5.

TABLE 5

Characteristics of Light Hydrocarbon Liquid Distillate

	Initial Boiling Point	140° C.-160° C.
	API Gravity	22-30
	Kinematic Viscosity	5-7 cSt (at 140° F.)

Typical Carbon Content	83-84	wt %
Typical Hydrogen Content	11-12	wt %
Typical Sulfur Content	1.5	wt %
Micro Carbon Residue	~1	wt %

Bromine Number

19

Olefin Content	20-24	wt %
Sara Analysis -
Pentane Solvent
Saturates	35	wt %
Aromatics	50-60	wt %
Resins	10-15	wt %
Asphaltenes	<1	wt %

Two exemplary components of the light hydrocarbon liquid distillate include naphtha and kerosene. Both naphtha and kerosene include aromatics and naphthenes for dissolving bitumen, making the light hydrocarbon liquid distillates suitable for use as first solvents. The table below summarizes key characteristics of the exemplary components of the light hydrocarbon liquid distillate. Because both naphtha and kerosene include about 60 wt % solvating components, naphtha and kerosene have about equal solvating (bitumen dissolution) power.

TABLE 5a

Solvating Component Content of Light
Hydrocarbon Liquid Distillates

		Naphtha	Kerosene

Boiling Point Range (° C.)

145-190

190-260

Typical Yield from Bitumen	4	wt %	10	wt %
Cracking in Nozzle Reactor
Content of Solvating
Components for Bitumen
Dissolution
Aromatics	27	wt %	34	wt %
Naphthenes	33	wt %	30	wt %

In step 350, the light hydrocarbon liquid distillate produced during step 340 may be mixed with a second quantity of material comprising bitumen. In this regard, step 350 is similar or identical to step 130 described in greater detail above. The light hydrocarbon liquid distillate may act as a suitable solvent for dissolving the bitumen content of the material comprising bitumen. As such, the light hydrocarbon distillate may be used in the first mixing step 300 described above. In certain embodiments, the light hydrocarbon liquid distillate may supplement or replace the first solvent used in the first mixing step.
As with the previous embodiments, the method may include additional steps for processing the first solvent-wet tailing phase separated from the bitumen-enriched solvent phase in step 310. Processing of the first solvent-wet tailings may include a step of mixing the first solvent-wet tailings with a second solvent to form a second mixture, separating the second mixture into a first solvent-enriched second solvent phase and a second solvent-wet tailings, and separating the second solvent from the second solvent-wet tailings. These steps may be similar or identical to the steps described above, including the use of a volatile hydrocarbon solvent as the second solvent, the option of using a plate and frame filter press for the separation step, the option of using a countercurrent washing process to perform the mixing and separation steps, and the use of a flashing unit or pre-heated gas to separate second solvent from the second solvent-wet tailings.
In some embodiments, a system for obtaining light hydrocarbon liquid distillate from material comprising bitumen includes mixers, separators and nozzle reactors. The system may include a first mixer for mixing a material comprising bitumen and a first solvent to form a first mixture, a first separator for separating the bitumen-enriched solvent from the first mixture, a nozzle reactor for cracking the bitumen component of the bitumen enriched solvent phase into a light hydrocarbon liquid distillate, and a recycle stream for recycling the light hydrocarbon distillate back to the first mixer.
FIG. 4 is a schematic diagram illustrating a system for obtaining light hydrocarbon distillate from material comprising bitumen. A material comprising bitumen 400 and a first solvent 410 may be routed to a first mixer 420. The material comprising bitumen 400 and first solvent 410 may be mixed in first mixer 420 as described above in connection with step 100. For example, the material comprising bitumen 400 and the first solvent 410 may be mixed by the agitation caused by introducing the components into the first mixer 420 or by a powered mixing device.
The material comprising bitumen 400 and the first solvent 410 may be as described above in the method of the previous embodiment. In one specific example, the material comprising bitumen 400 may be tar sands and the first solvent 410 may be a light aromatic solvent. The material comprising bitumen 400 and the first solvent may be mixed according to the ratios set forth above in the description of step 100.
Once mixed together, the material comprising bitumen 400 and the first solvent 410 form a first mixture 430. The first mixture may be routed to a first separator 440, such as by pumping the first mixture 430 through piping fluidly connecting the first mixer 420 and the first separator. In an alternate embodiment, the first mixer 420 and the first separator 440 may be the same vessel.
The first separator 440 separates bitumen-enriched solvent phase 450 from the first mixture 430. Removal of the bitumen-enriched solvent phase 450 results in the first mixture 430 becoming first solvent-wet tailings 460, which may be discharged from the first separator 440. The first separator 440 may be any type of separator suitable for separating the bitumen-enriched solvent phase 450 from the first mixture 430. As discussed above in greater detail, the bitumen-enriched solvent phase 450 may be separated from the first mixture 430 by, for example, settling, filtering or by performing gravity drainage on the first mixture 430. Accordingly, first separator 440 may be, for example, a settling vessel, a filtration vessel or a gravity drainage vessel. As also discussed above, first separator 440 may perform a two stage separation, with the second stage involving the addition of further first solvent to the first mixture 430 to displace residual bitumen-enriched solvent phase remaining in the first mixture 430 after the first stage of separation.
The bitumen-enriched solvent phase 450 is routed to a nozzle reactor 470, such as by pumping the bitumen-enriched solvent phase 450 through piping fluidly connecting the first separator 440 and the nozzle reactor 470. The bitumen-enriched solvent phase 450 is injected into the nozzle reactor 470 and at least a portion of the bitumen component of the bitumen-enriched solvent phase 450 is cracked into lighter hydrocarbon material.
As discussed in greater detail above, the nozzle reactor 470 can be any nozzle reactor wherein differing types of materials are injected into an interior reactor chamber of the nozzle reactor 470 and caused to interact within the interior reactor chamber in order to alter the mechanical or chemical composition of one or more of the materials. In certain embodiments, the nozzle reactor 470 may be a nozzle reactor as described in co-pending U.S. application Ser. No. 11/233,385. In such a nozzle reactor, a cracking material 475 is injected into the interior reaction chamber of the nozzle reactor 470 at an accelerated and possibly supersonic speed, while the bitumen-enriched solvent phase 450 is injected into the interior reaction chamber of the nozzle reactor 470 at a direction transverse to the direction that the cracking material 475 is injected into the nozzle reactor 470.
The interaction between the bitumen component and the cracking material 475 cracks at least a portion of the bitumen component. A portion of the bitumen component that is cracked is cracked into a light hydrocarbon liquid distillate 480 having a molecular weight less than 300 Daltons. Other components of the bitumen-enriched solvent phase 450 may be cracked, but not to the molecular weight range for light hydrocarbon distillate 480. Still other components of the bitumen-enriched solvent phase 450 may not be cracked inside the nozzle reactor 470 and will exit the nozzle reactor 470 in the same condition as when it entered the nozzle reactor 470. The uncracked material and the material cracked to a molecular weight outside of the range for light hydrocarbon distillate 480 are considered non-participating hydrocarbon. Accordingly, the nozzle reactor 470 may produce a light hydrocarbon distillate stream 480 and a combined non-participating hydrocarbon stream 490.
The combined non-participating hydrocarbon stream 490 may include hydrocarbon material that is suitable for use as a commercial product or that requires further processing to upgrade the hydrocarbon material into a useful commercial product. Accordingly, combined non-participating hydrocarbon stream 490 may be collected for consumption and/or subjected to further processing to upgrade the hydrocarbon material into useful products. In certain embodiments, the combined non-participating hydrocarbon stream 490 may be injected into a second nozzle reactor for further attempts at cracking the non-participating hydrocarbons.
The light hydrocarbon distillate 480 may be recycled within the system for use in mixer 420. That is to say, the light hydrocarbon distillate 480 may be mixed with material comprising bitumen 400 in mixer 420 to begin the process of extracting bitumen from the material comprising bitumen 400. The light hydrocarbon distillate 480 may supplement first solvent 410 to provide a sufficient amount of solvent to mix with the material comprising bitumen 400 in the mixer 420, or may replace the first solvent 410 such that only light hydrocarbon distillate 480 is mixed with material comprising bitumen 400 in first mixer 420. A light hydrocarbon distillate bleed stream 485 may also be included in the system such that the light hydrocarbon distillate is not constantly recycled within the system.
In addition to the light hydrocarbon distillate 480 and combined non-participating hydrocarbon stream 490, the nozzle reactor 470 may also emit cracking material that has not participated in a chemical reaction with the bitumen-enriched solvent phase 450. The nozzle reactor 470 may also emit a small amount of gaseous product produced inside the nozzle reactor, such as hydrogen and methane.
FIG. 5 shows how the system illustrated in FIG. 4 may also include equipment for processing the first solvent-wet tailings 460. First solvent-wet tailings 460 may be transported to a second separator 500, such as by pumping the first solvent-wet tailings 460 through piping fluidly connecting the first separator 440 with the second separator 500. A second solvent 510 may be added to the first solvent wet tailings 460 in the second separator 500, which results in the displacement of first solvent out of the first solvent-wet tailings 460. Second solvent 510 may be added to the first solvent-wet tailings 460 in any amount described above and according to any to procedure described above. For example, the second solvent 510 may be added to the first solvent-wet tailings 460 in a countercurrent washing process.
The first solvent leaves the second separator 500 as a first solvent-second solvent mixture 520. The addition of second solvent 510 to the first solvent-wet tailings 460 results in the first solvent-wet tailings 460 becoming second solvent-wet tailings 530 due to some of the second solvent 510 remaining in the tailings.
The first solvent-second solvent mixture 520 may be sent to a third separator 540, such as by pumping the first solvent-second solvent mixture 520 through piping fluidly connecting the second separator 500 and the third separation unit 540. The first solvent-second solvent mixture 520 is separated into first solvent 550 and second solvent 560. The third separator 540 may be any type of separator suitable for separating first solvent 550 and second solvent 560, such as a still. The first solvent 550 may then be recycled back in the system for use in the first mixer 420. The first solvent 550 may supplement or eliminate the first solvent 410 used to carry out the solvent extraction of bitumen in mixer 420. In certain embodiments, the first solvent 550 may be used with the light hydrocarbon distillate 480 to eliminate the need for first solvent 410. Similarly, the second solvent 560 may be recycled back in the system for use in the second separator 500. The second solvent 560 may be used to supplement or eliminate the second solvent 510.
The second solvent-wet tailings 530 are transported to a fourth separator 570, such as by pumping the second solvent-wet tailings 530 through piping fluidly connecting second separator 500 and the fourth separator unit 570. The fourth separator 570 separates the second solvent from the second solvent-wet tailings 530. Fourth separator 570 may be any suitable type of separator for separating second solvent from the second solvent-wet tailings 530, such as a heating or flashing unit. Second solvent stream 580 produced by fourth separator 570 may be recycled back to second separator 500 for use with, or in place of, second solvent 510. Fourth separator 570 also produces a tails stream 590 that contains little or no second solvent.
FIG. 6 is a schematic diagram illustrating a system similar to the system illustrated in FIG. 4, but including further processing equipment for conducting deasphalting on bitumen material. As with FIG. 4, the system includes a first mixer 610 for mixing material comprising bitumen 600 with first solvent 605 and a first separator 620 for separating a bitumen-enriched solvent phase 625 from a first mixture 615 and producing first solvent-wet tailings 630 by the removal of the bitumen-enriched solvent phase 625 from the first mixture 615.
In the case of the system illustrated in FIG. 6, the bitumen-enriched solvent phase 625 undergoes further processing prior to being injected into a nozzle reactor 670. Firstly, the bitumen-enriched solvent phase 625 is transported to second separator 635 for separating the bitumen-enriched solvent phase 625 into bitumen component 640 and first solvent 645. The second separator 635 may be any suitable separator for separating first solvent 645 from the bitumen component 640, such as a heater that evaporates the first solvent 645 from the bitumen-enriched solvent phase 625. The first solvent 645 may be recycled back within the system to the first mixer 610, where it may supplement or eliminate the first solvent 605.
The bitumen component 640 obtained from the second separation unit 635 is transported to a deasphalter 650. The deasphalter 650 may perform any suitable type of deasphalting step on the bitumen component 640, such as the ROSE™ process or propane solvent deasphalting process discussed previously. Deasphalting unit 650 produces an asphaltene stream 655 and a hydrocarbon stream 660. The hydrocarbon stream 660 may be collected to undergo further processing for the purpose of producing commercially useful product. The asphaltene stream 655 is injected into the nozzle reactor 670.
From this point on, the system shown in FIG. 6 is again similar to the system shown in FIG. 4. Cracking material 665 is injected into the nozzle reactor 670 at supersonic speeds to create shockwaves that crack portions of the asphaltene stream 655 injected into the nozzle reactor 670. Some of the asphaltene stream 655 will be cracked to produce light hydrocarbon distillate 680, while the remainder of the asphaltene stream 655 will become the non-participating hydrocarbon stream 675. Like hydrocarbon stream 660, the non-participating hydrocarbon stream 675 may undergo further processing (such as being passed through a second nozzle reactor) to create commercially useful products. Light hydrocarbon distillate 680 may be recycled within the system to be used in the first solvent extraction of bitumen from material comprising bitumen 600. The light hydrocarbon distillate may be used to supplement the first solvent 605 and/or first solvent 645, or may be used eliminate the need for first solvent 605 and first solvent 645. A light hydrocarbon distillate bleed stream 685 may also be included in the system such that the light hydrocarbon distillate is not constantly recycled within the system.
FIG. 7 shows how the system illustrated in FIG. 6 may also include equipment for processing the first solvent-wet tailings 630. First solvent-wet tailings 630 may be transported to a third separator 700, such as by pumping the first solvent-wet tailings 630 through piping fluidly connecting the first separator 620 with the third separator 700. A second solvent 705 is added to the first solvent-wet tailings 630 loaded in the third separator 700 to displace first solvent from the first solvent-wet tailings 630. The second solvent 705 may be any of the second solvents described previously and mixing may be carried out as described in greater detail above. The third separator 700 may be any type of separator, such as a plate and frame-type filter press.
The first solvent-second solvent mixture 710 is transported to a fourth separator 715, such as by pumping the first solvent-second solvent mixture 710 through piping fluidly connecting the third separator 700 and the fourth separator 715. The first solvent-second solvent mixture 710 is separated into first solvent 720 and second solvent 725. The fourth separator 715 may be any type of separation unit suitable for separating first solvent 720 and second solvent 725, such as a still. The first solvent 720 may then be recycled back in the system for use in the first mixer 610. The first solvent 720 may supplement the first solvent 605, first solvent 645 and/or the light hydrocarbon distillate 680 used to carry out the solvent extraction of bitumen in mixer 610. Similarly, the second solvent 725 may be recycled back in the system for use in the second separator 700. The second solvent 725 may be used to supplement or eliminate the second solvent 705.
The second solvent-wet tailings 730 are transported to a fifth separator 735, such as by pumping the second solvent-wet tailings 730 through piping fluidly connecting third separator 700 and the fifth separator 735. The fifth separator 735 separates the second solvent from the second solvent-wet tailings 730. Fifth separator 735 may be any suitable type of separator for separating second solvent from the second solvent-wet tailings 730, such as a heating or flashing unit. Second solvent stream 745 produced by fifth separator 735 may be recycled back to third separator 700 for use with, or in place of, second solvent 705 and/or second solvent 725. Fifth separator 735 also produces a tails stream 740 that contains little or no second solvent.
FIG. 8 is a schematic diagram illustrating a system that falls between the systems shown in FIGS. 4 and 6. More specifically, the system includes a separator 635 for separating the bitumen-enriched solvent phase 625 into bitumen component 640 and first solvent 645, but does not include a deasphalter. As such, the bitumen component 640 is injected into the nozzle reactor 670 without first undergoing a deasphlating step. FIG. 9 shows the system of FIG. 8 together with additional units for processing the first solvent-wet tailings 630.
In view of the many possible embodiments to which the principles of the disclosed invention may be applied, it should be recognized that the illustrated embodiments are only preferred examples of the invention and should not be taken as limiting the scope of the invention. Rather, the scope of the invention is defined by the following claims. We therefore claim as our invention all that comes within the scope and spirit of these claims.

EXAMPLES

The following examples are provided to further illustrate the subject matter disclosed herein. These examples should not be considered as being limiting in any way.
In the following examples, bitumen was extracted from three different tar sands—Trinidad tar sands (“Trinidad”), high grade Athabasca tar sands (“AthHG”), and low grade Athabasca tar sands (“AthLG”). The composition of each tar sand material is shown in Table 6 along with a brief description. The composition of each tar sands was determined using a Dean-Stark apparatus. Before being used in the examples, the tar sands were broken by hand into pieces small enough to fit through a 0.5 inch diameter hole.
The bitumen was extracted from the tar sands using a multi-stage extraction process that included two solvent extraction steps. The tar sands were initially mixed with a liquid solvent (the particular solvent is specified in the examples) at atmospheric pressure. The mixture was separated into a bitumen-enriched first solvent phase and first solvent-wet tailings.
The first solvent-wet tailings were combined with LPG in a pipe. The pressure in the pipe was sufficient to keep the LPG in a liquid form. This combination was separated into a first solvent-enriched second solvent phase and second solvent-wet tailings.
The bitumen-enriched first solvent phase was injected into a nozzle reactor. Steam was also injected into the nozzle reactor in order to crack at least a portion of the bitumen in the bitumen-enriched first solvent phase. The nozzle reactor produced light distillate and a non-participating hydrocarbon stream.

TABLE 6

Tar sands

	Bitumen	Water
Sample	(wt %)	(wt %)	Description

Trinidad	12	4.6	A blend of drill core samples
			obtained from a tar sands
			in Trinidad.
AthHG	12	4	A high grade tar sand sample
			from the Athabasca Tar sands
			in Alberta, Canada.
AthLG	8	5.5	A low grade tar sand sample
			from the Athabasca Tar sands
			in Alberta, Canada.

Example 1

Trinidad Tar Sands

In this example, bitumen was extracted from a total of eleven samples of a Trinidad tar sand project. The samples are designated T-1 through T-11 in Table 7. The details of the extraction of each sample can be found in Table 7 along with some observations taken during each process.
Except as noted otherwise, each sample was processed using the following procedure. Each sample was initially weighed and the sample was placed into a mixing container along with the necessary amount of the first solvent to achieve the proper solvent to bitumen ratio specified in Table 7. The first solvent and the tar sands were mixed with a standard three blade impeller. The tar sands were leached for one hour in the mixing container. The mixture was then filtered with a Buchner funnel with filter paper, either with gravity or under vacuum or under atmospheric pressure, to separate the liquids from the solids. The filtrate of liquids formed a bitumen-enriched solvent phase and the filter cake of solids formed first solvent-wet tailings.
The first solvent-wet filtrate was weighed and measured. The first solvent-wet filter cake was subjected to addition of a second solvent to remove any remnants of the first solvent in the filter cake. The amount of the first solvent still present in the first solvent-wet filter cake varied depending on the filtration time and the particular solvent used.
The addition of the second solvent was performed by placing the first solvent-wet filter cake into a pipe extractor and introducing liquid LPG into the pipe extractor (commercial LPG was used). The liquid LPG displaced any remaining amounts of the first solvent from the first solvent-wet filter cake. The first solvent-wet filter cake was soaked in the liquid LPG for fifteen minutes. The liquids and solids in the mixture were separated into a first solvent-second solvent mixture and second-solvent wet tailings, respectively. The first solvent-second solvent mixture included liquid LPG, bitumen, and first solvent. The LPG was removed from the bitumen and first solvent by allowing it to vaporize within the system. The bitumen and the first solvent (both in the form of a liquid) were then captured in a flask. The weight and amount of the liquids were measured. The remaining solids in the pipe were also removed and weighed.
Some of the samples were extracted using the same procedure described above with some subtle differences. Sample T-3 was mixed with the first solvent in the mixing pipe followed directly by the LPG soaking. Samples T-6 and T-7 were the same except that the filter cake from T-6 was completely dry when placed in the pipe extractor and the filter cake from T-7 was still wet when placed in the pipe. Sample T-9 was extracted using a three step process that included initially extracting bitumen with liquid LPG in the pipe, separating the liquids and the solids, leaching the solids with the first solvent in the mixing container, separating the liquids and the solids, and extracting the bitumen and any remaining amounts of the first solvent in the pipe extractor with LPG.
The results of the extraction process are shown in Table 8Table. The total weight loss is the difference between the weight of the tar sands feedstock and the weight of the second solvent-wet tailings component removed from the pipe extractor. The American Petroleum Institute (API) gravity was determined for the liquid extracted from the pipe extractor. The second solvent-wet tailings removed from the pipe extractor were analyzed using the Dean-Stark apparatus to determine the amount of bitumen in the second solvent-wet tailings.
The amount of bitumen in the tar sands feedstock can be calculated using this equation: bitumen in tar sands feedstock (wt %)=total weight loss (wt %)−water in tar sands feedstock (wt %)+(100−total weight loss (wt %))*fraction of bitumen in second solvent-wet tailings. Using sample T-1 as an example, the calculation was as follows: Bitumen in tar sands feedstock (wt %)=18.13−4.6+(100−18.13)*0.0205. The percent of the bitumen that was extracted can then be calculated using this equation: (bitumen in tar sands feedstock (wt %)−(100−total weight loss (wt %))*fraction of bitumen in second solvent-wet tailings)/bitumen in tar sands feedstock (wt %). Using sample T-1 as an example, the calculation was as follows: (15.20−(100−18.13)*0.0205)/15.20.

TABLE 7

Trinidad Extraction Process Parameters

Description

	First	S:B	First	Second
Sample	Solvent	Ratio	Extraction	Extraction

T-1	Biodiesel	14:1	1 hour filtration
T-2	Toluene	5:1	4-5 hour filtration	Filter cake solids
				compacted in pipe
T-3	Toluene	20:1		Toluene flow slow out of
				pipe, very compact cake
T-4	Xylene	10:1	Filtered overnight	Solids poured out easily
T-5	Toluene	10:1	3-5 minute filtration	No liquid from pipe
T-6	Light	10:1	3-5 minute filtration,	Sands easily removed, high
	Distillate*		dry filter cake	viscosity liquid recovered
T-7	Light	10:1	20 minute filtration,	Sands easily removed low
	Distillate*		wet filter cake	viscosity liquid recovered
T-8	Light	5:1	3-5 minute filtration,	Sands removed as one big
	Distillate*		wet filter cake	clump, low viscosity
				liquid recovered

T-9	Light	10:1	First extraction: LPG resulted in compacted cake
	Distillate*		Second extraction: filtered first solvent for one hour
			Third extraction: sands removed easily, low viscosity liquid

T-10	Naphtha	10:1	3-5 minute filtration,	Solids removed very easily
			dry filter cake
T-11	Naphtha	5:1	3-5 minute filtration,	Solids removed very easily
			dry filter cake

*Light distillate solvent used has an API gravity of approximately 30. The light distillate includes highly aromatic compounds such as toluene, xylene, some benzene, and other ring compounds. The light distillate was obtained by steam cracking bitumen as described in U.S. Patent Application Publication No. 2006/0144760.

TABLE 8

Trinidad Extraction Results

				Bitumen in
		API Gravity	Bitumen in Second	Tar Sands	Total Bitumen
	Weight	of Extracted	Solvent-Wet	Feedstock	Extracted
Sample	Loss (%)	Liquid	Tailings (wt %)	(wt %)	(wt %)

T-1	18.1	21.0	2.1	15.2	88.9
T-2	17.6	—	—	—	—
T-3	18.1	23.1	—	—	—
T-4	17.5	—	—	—	—
T-5	18.0	—	—	—	—
T-6	14.1	9.2	2.6	11.7	81.3
T-7	14.7	9.8	3.3	12.9	78.3
T-8	15.3	21.5	3.3	13.4	79.2
T-9	18.4	28.5	4.8	17.7	78.0
T-10	14.7	—	—	—	—
T-11	17.2	—	1.7	13.9	90.2

The bitumen-enriched solvent phase obtained from sample T-8 was preheated to a temperature of 400° C. using a sand bath heater. The bitumen-enriched solvent phase was then injected into a nozzle reactor of the type described in U.S. Patent Application Publication No. 2006/0144760. The bitumen-enriched solvent phase was injected into the nozzle reactor via the material feed port of the nozzle reactor. Steam at a pressure of 20 bar was also injected into the nozzle reactor via a injection passage positioned transverse to the material feed passage. Steam and bitumen-enriched solvent phase were injected into the nozzle reactor at a steam:bitumen-enriched solvent phase at a ratio of 2:1. The pressure inside of the nozzle reactor at injection was 1.5 bar. The dimensions of the nozzle are set forth in Table 9. The injected bitumen-enriched solvent phase remained in the nozzle reactor for a period of about 1 second.

	TABLE 9

	Nozzle Reactor Component (mm)

	Injection Passage, Enlarged Volume	148
	Injection Section Diameter
	Injection Passage, Reduced Volume	50
	Mid-Section Diameter
	Injection Passage, Enlarged Volume	105
	Ejection Section Diameter
	Injection Passage Length	600
	Interior Reactor Chamber	187
	Injection End Diameter
	Interior Reactor Chamber	1,231
	Ejection End Diameter
	Interior Reactor Chamber Length	6,400
	Overall Nozzle Reactor Length	7,000
	Overall Nozzle Reactor Outside	1,300
	Diameter

A liquid product exiting the nozzle reactor was collected and analyzed. The product was separated into a non-participating hydrocarbon stream and a participating hydrocarbon stream. The participating hydrocarbon stream had an API gravity in the range of from 28-35. The participating hydrocarbon stream contained a mixture of cracked hydrocarbons. The mixture included highly aromatic compounds such as toluene, xylene, some benzene, and other ring compounds. The molecular weight of the compounds in the participating hydrocarbon stream generally were less than 300 Daltons. The participating hydrocarbon stream was classified as a light distillate of the type usable as a first solvent in a solvent extraction step of the method described above.

Example 2

AthHG Tar Sands

In this example, Bitumen was extracted from a total of four samples of high grade Athabasca tar sands. The samples are designated AHG-1 through AHG-4 in Table 10. The details of the extraction of each sample can be found in Table 10 along with some observations taken during each process.
The same general procedure outlined in Example 1 was used to extract bitumen from the high grade Athabasca tar sands samples with a few minor exceptions. Some of the samples were mixed with a bowtie shaped coil impeller instead of the three blade impeller. The coil impeller was used to ensure adequate mixing and dispersion of the large pieces of clay in the samples. The samples mixed with the coil impeller are noted in Table 10.
In general, it was more difficult to quickly and efficiently filter the high grade Athabasca tar sands than the Trinidad tar sands. For example, Sample AHG-1 did filter, but it was left overnight and there was no loose liquid remaining with the filter cake by morning. Also, Sample AHG-2 used the coil impeller which helped it to filter steadily but it was still somewhat slow. Sample AHG-4 was similar to Samples AHG-1 and AHG-3 except there was no loose liquid with the filter cake when it was placed in the pipe extractor. The results of the extraction process are shown in Table 11. It should be noted that Table 11 also shows the API gravity of the liquid filtrate resulting from the first extraction process.

TABLE 10

AthHG Extraction Process Parameters

Description

	First	S:B	First	Second
Sample	Solvent	Ratio	Extraction	Extraction

AHG-1	Light	5:1	Filtered	Solids removed
	Distillate		overnight, moist	easily
			filter cake
AHG-2	Biodiesel	5:1	Mixed with coil	Solids were
			impeller, two	slightly packed
			hour atm filter*
AHG-3	Light	5:1	Mixed with coil	Liquid removed
	Distillate		impeller, atm	during N2 purge
			filtered
			overnight*, very
			moist filter cake
AHG-4	Light	5:1	Filters slow	Solids were
	Distillate			quite dark

*Filtered using Buchner filter with paper at atmospheric pressure (i.e., no vacuum).

TABLE 11

AthHG Extraction Results

		API	API Gravity	Bitumen in	Bitumen in	Total Bitumen
	Weight	Gravity	of Extracted	Residual Tar	Feedstock	Extracted
Sample	Loss (%)	of Filtrate	Liquid	Sands (wt %)	(wt %)	(wt %)

AHG-1	17.3	28.4	39.5	1.9	16.7	90.7
AHG-2	19.6	28.5	29.6	1.7	17.0	91.7
AHG-3	16.9	29.8	26.5	2.3	14.9	87.1
AHG-4	17.0	31.5	29.9	2.4	14.9	86.7

The bitumen-enriched solvent phase obtained from sample AHG-1 was preheated to a temperature of 400° C. using a sand bath heater. The bitumen-enriched solvent phase was then injected into a nozzle reactor of the type described in U.S. Patent Application Publication No. 2006/0144760. The bitumen-enriched solvent phase was injected into the nozzle reactor via the material feed port of the nozzle reactor. Steam at a pressure of 20 bar was also injected into the nozzle reactor via an injection passage positioned transverse to the material feed passage. Steam and bitumen-enriched solvent phase were injected into the nozzle reactor at a steam:bitumen-enriched solvent phase at a ratio of 2:1. The pressure inside of the nozzle reactor at injection was 1.5 bar. The dimensions of the nozzle are set forth in Table 9 above. The injected bitumen-enriched solvent phase remained in the nozzle reactor for a period of about 1 second.
A liquid product exiting the nozzle reactor was collected and analyzed. The product was separated into a non-participating hydrocarbon stream and a participating hydrocarbon stream. The participating hydrocarbon stream had an API gravity of approximately 28. The participating hydrocarbon stream contained a mixture of cracked hydrocarbons. The mixture included highly aromatic compounds such as toluene, xylene, some benzene, and other ring compounds. The molecular weight of the compounds in the participating hydrocarbon stream generally were less than 300 Daltons. The participating hydrocarbon stream was classified as a light distillate of the type usable as a first solvent in a solvent extraction step of the method described above.

Example 3

AthLG Tar Sands

In this example, Bitumen was extracted from a total of four samples of low grade Athabasca tar sands. The samples are designated ALG-1 through ALG-8 in Table 12. The details of the extraction of each sample can be found in Table 12 along with some observations taken during each process.
The same general procedure outlined in Example 1 was used to extract bitumen from the low grade Athabasca tar sands samples with a few minor exceptions. Sample ALG-4 did not undergo the first extraction process and instead was put directly into the pipe extractor. No liquid was recovered from the second extraction process (LPG extraction process) for Sample ALG-2. Sample ALG-3 used biodiesel as the first solvent and was able to filter fast. A coil impeller was used to mix the first solvent and the tar sands. The mixture was subjected to a thirty minute vacuum filtration and thirty minute atmospheric filtration. The filter cake was allowed to air dry under room temperature overnight before entering the pipe extractor. The solids were removed from the pipe extractor quite easily. The low grade Athabasca tar sands was easily processed though the system. The results of the extraction process are shown in Table 13.

TABLE 12

AthLG Extraction Process Parameters

Description

	First		First	Second
Sample	Solvent	Ratio	Extraction	Extraction

ALG-1	Light	6:1	Filters very fast	Solids removed
	Distillate			easily, light
				liquid
ALG-2	Naphtha	6:1	Filtered instantly	Solids removed
				easily, no
				liquid capture
ALG-3	Biodiesel	6:1	Filtered fast	Few chunks of
				dark solids
ALG-4	—	20:1	—	Solids were
				tightly packed
				in the pipe,
				minimal liquid
				recovered
ALG-5	Light	5:1	Filtered instantly,	Solids removed
	Distillate		heavy filter cake	easily
ALG-6	Light	5:1	Filtered instantly,	Solids removed
	Distillate		heavy filter cake	easily
ALG-7	Light	5:1	Dry feed, filtered	Lots of liquid
	Distillate		for 2 days but still	recovered
			moist, very compact
			dark filter cake
ALG-8	Light	5:1	Filtered fast	Solids were very
	Distillate			dry, no large
				clumps of
				asphaltenes, few
				pellets of clay

TABLE 13

AthLG Extraction Results

		API	API Gravity	Bitumen in	Bitumen in	Total Bitumen
	Weight	Gravity	of Extracted	Residual Tar	Feedstock	Extracted
Sample	Loss (%)	of Filtrate	Liquid	Sands (wt %)	(wt %)	(wt %)

ALG-1	13.7	31.6	42.1	1.4	8.4	85.9
ALG-2	15.2	54.5	—	—	—	—
ALG-3	16.5	48.1	13.9	—	—	—
ALG-4	10.8	—	13.9	8.0	11.4	37.8
ALG-5	11.0	32.1	38.3	3.2	7.4	61.3
ALG-6	13.1	29.2	29.1	2.7	8.9	73.9
ALG-7	6.2	27.4	26.9	6.0	11.2	49.8
ALG-8	10.0	27.8	31.5	2.1	69.3	64.2

The bitumen-enriched solvent phase obtained from sample ALG-1 was preheated to a temperature of 400° C. using a sand bath heater. The bitumen-enriched solvent phase was then injected into a nozzle reactor of the type described in U.S. Patent Application Publication No. 2006/0144760. The bitumen-enriched solvent phase was injected into the nozzle reactor via the material feed port of the nozzle reactor. Steam at a pressure of 20 bar was also injected into the nozzle reactor via an injection passage positioned transverse to the material feed passage. Steam and bitumen-enriched solvent phase were injected into the nozzle reactor at a steam:bitumen-enriched solvent phase at a ratio of 2:1. The pressure inside of the nozzle reactor at injection was 1.5 bar. The dimensions of the nozzle are set forth in Table 9 above. The injected bitumen-enriched solvent phase remained in the nozzle reactor for a period of about 1 second.

A liquid product exiting the nozzle reactor was collected and analyzed. The product was separated into a non-participating hydrocarbon stream and a participating hydrocarbon stream. The participating hydrocarbon stream had an API gravity of approximately 28. The participating hydrocarbon stream contained a mixture of cracked hydrocarbons. The mixture included highly aromatic compounds such as toluene, xylene, some benzene, and other ring compounds. The molecular weight of the compounds in the participating hydrocarbon stream generally were less than 300 Daltons. The participating hydrocarbon stream was classified as a light distillate of the type usable as a first solvent in a solvent extraction step of the method described above.
As used herein, spatial or directional terms, such as “left,” “right,” “front,” “back,” and the like, relate to the subject matter as it is shown in the drawing Figures. However, it is to be understood that the subject matter described herein may assume various alternative orientations and, accordingly, such terms are not to be considered as limiting. Furthermore, as used herein (i.e., in the claims and the specification), articles such as “the,” “a,” and “an” can connote the singular or plural. Also, as used herein, the word “or” when used without a preceding “either” (or other similar language indicating that “or” is unequivocally meant to be exclusive—e.g., only one of x or y, etc.) shall be interpreted to be inclusive (e.g., “x or y” means one or both x or y). Likewise, as used herein, the term “and/or” shall also be interpreted to be inclusive (e.g., “x and/or y” means one or both x or y). In situations where “and/or” or “or” are used as a conjunction for a group of three or more items, the group should be interpreted to include one item alone, all of the items together, or any combination or number of the items. Moreover, terms used in the specification and claims such as have, having, include, and including should be construed to be synonymous with the terms comprise and comprising.
Unless otherwise indicated, all numbers or expressions, such as those expressing dimensions, physical characteristics, etc., used in the specification (other than the claims) are understood as modified in all instances by the term “approximately.” At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the claims, each numerical parameter recited in the specification or claims which is modified by the term “approximately” should at least be construed in light of the number of recited significant digits and by applying ordinary rounding techniques.
In addition, all ranges disclosed herein are to be understood to encompass and provide support for claims that recite any and all subranges or any and all individual values subsumed therein. For example, a stated range of 1 to 10 should be considered to include and provide support for claims that recite any and all subranges or individual values that are between and/or inclusive of the minimum value of 1 and the maximum value of 10; that is, all subranges beginning with a minimum value of 1 or more and ending with a maximum value of 10 or less (e.g., 5.5 to 10, 2.34 to 3.56, and so forth) or any values from 1 to 10 (e.g., 3, 5.8, 9.9994, and so forth).

Claims

1. A method comprising:

forming a first mixture by mixing a first quantity of material comprising bitumen with a first solvent, wherein the first mixture comprises a bitumen-enriched solvent phase;

separating the bitumen-enriched solvent phase from the first mixture and thereby producing first solvent-wet tailings, wherein the bitumen-enriched solvent phase comprises a bitumen component and the first solvent-wet tailings comprise a first solvent component;

forming a light hydrocarbon liquid distillate and a non-participating hydrocarbon stream by cracking bitumen component inside a first nozzle reactor; and

mixing the light hydrocarbon liquid distillate with a second quantity of material comprising bitumen.

2. The method as claimed in claim 1, further comprising:

separating the first solvent component from the first solvent-wet tailings by adding a second solvent to the first solvent-wet tailings and thereby producing second solvent-wet tailings, wherein the second solvent-wet tailings comprise a second solvent component; and

separating the second solvent component from the second solvent-wet tailings.

3. The method as recited in claim 1, wherein separating the bitumen-enriched solvent phase from the first mixture comprises:

a first stage of separating a first quantity of the bitumen-enriched solvent phase from the first mixture by filtering, settling or draining the bitumen-enriched solvent phase from the first mixture; and

a second stage of separating a second quantity of the bitumen-enriched solvent phase from the first mixture by adding a second quantity of first solvent to the first mixture.

4. The method as recited in claim 3, wherein the second stage of separating a second quantity of the bitumen-enriched solvent phase from the first mixture comprises washing the first mixture with the second quantity of first solvent in a countercurrent process.

5. The method as recited in claim 2, wherein separating the first solvent component from the first solvent-wet tailings comprises washing the first solvent-wet tailings with the second solvent in a countercurrent process.

6. The method as recited in claim 2, wherein separating the second solvent from the second solvent-wet tailings comprises flashing the second solvent component from the second solvent-wet tailings.

7. The method as recited in claim 1, wherein separating the bitumen-enriched solvent phase from the first mixture comprises filtering the first mixture in a plate and frame-type filter press.

8. The method as recited in claim 2, wherein separating the first solvent component from the first solvent-wet tailings comprises adding the second solvent to the first solvent-wet tailings loaded in a plate and frame-type filter press.

9. The method as recited in claim 7, wherein filtering the first mixture in a plate and frame-type filter press further comprises adding a gas over the first mixture loaded in the plate and frame-type filter press.

10. The method as recited in claim 8, wherein gas is added over the first solvent-wet tailings loaded in the plate and frame-type filter press.

11. The method as claimed in claim 1, further comprising:

cracking the non-participating hydrocarbon stream inside a second nozzle reactor.

12. The method as claimed in claim 1, wherein the material comprising bitumen is tar sands.

13. The method as claimed in claim 1, wherein the first solvent comprises a light aromatic solvent.

14. The method as claimed in claim 13, wherein the light aromatic solvent comprises kerosene, diesel, gas oil, naphtha, benzene, toluene, an aromatic alcohol, derivatives thereof, or a combination thereof.

15. The method as claimed in claim 2, wherein the second solvent comprises a volatile hydrocarbon solvent.

16. The method as claimed in claim 15, wherein the volatile hydrocarbon solvent comprises a cyclo- or iso-paraffin having between 3 and 9 carbons, derivatives thereof, or combinations thereof.

17. The method as claimed in claim 2, wherein the second solvent is liquefied petroleum gas.

18. The method as claimed in claim 1, wherein the first nozzle reactor comprises:

a reactor body having an interior reactor chamber with an injection end and an ejection end;

an injection passage mounted in the nozzle reactor in material injecting communication with the injection end of the interior reactor chamber, the injection passage having (a) an enlarged volume injection section, an enlarged volume ejection section, and a reduced volume mid-section intermediate the enlarged volume injection section and enlarged volume ejection section, (b) a material injection end, and (c) a material ejection end in injecting communication with the interior reactor chamber; and

a material feed passage penetrating the reactor body and being (a) adjacent to the material ejection end of the injection passage and (b) transverse to an injection passage axis extending from the material injection end to the material ejection end in the injection passage.

19. The method as claimed in claim 1, wherein the light hydrocarbon liquid distillate comprises hydrocarbon having a molecular weight less than 300 Daltons.

20. The method as claimed in claim 1, wherein cracking bitumen component inside the first nozzle reactor comprises:

injecting a stream of cracking material through an injection passage into an interior reactor chamber; and

injecting the bitumen component into the interior reactor chamber adjacent to the injection passage and transverse to the stream of cracking material entering the interior reactor chamber from the injection passage.

21. The method of claim 1, further comprising:

separating the bitumen-enriched solvent phase into bitumen component and a first solvent phase prior to cracking the bitumen component inside a first nozzle reactor.

22. The method of claim 21, wherein separating the bitumen-enriched solvent phase into bitumen component and the first solvent phase comprises heating the bitumen-enriched solvent phase to a temperature above the boiling point temperature of the first solvent.

23. A method comprising:

separating the bitumen-enriched solvent phase from the first mixture and thereby producing first solvent-wet tailings, wherein the bitumen-enriched solvent phase comprises a bitumen component and a primary first solvent component and the first solvent-wet tailings comprise a secondary first solvent component;

separating the primary first solvent from the bitumen-enriched solvent phase to thereby isolate the bitumen component of the bitumen-enriched solvent phase;

producing an asphaltene stream by deasphalting bitumen component;

forming a light hydrocarbon liquid distillate and a non-participating hydrocarbon stream by cracking the asphaltene stream inside a first nozzle reactor; and

24. The method as claimed in claim 23, further comprising:

separating the secondary first solvent component from the first solvent-wet tailings by adding a second solvent to the first solvent wet tailings and thereby producing second solvent-wet tailings, wherein the second solvent-wet tailings comprise a second solvent component; and

separating the second solvent component from the second solvent-wet tailings.

25. The method as recited in claim 23, wherein separating the bitumen-enriched solvent phase from the first mixture comprises:

a first stage of separating a first quantity of the first bitumen-enriched solvent phase from the first mixture by filtering, settling or draining the bitumen-enriched solvent phase from the first mixture; and

a second stage of separating a second quantity of the first bitumen-enriched solvent phase from the first mixture by adding a second quantity of first solvent to the first mixture.

26. The method as recited in claim 25, wherein the second stage of separating the second quantity of the first bitumen-enriched solvent phase from the first mixture comprises washing the first mixture with the second quantity of first solvent in a countercurrent process.

27. The method as recited in claim 24, wherein separating the first solvent component from the first solvent-wet tailings comprises washing the first solvent-wet tailings with the second solvent in a countercurrent process.

28. The method as recited in claim 24, wherein separating the second solvent from the second solvent-wet tailings comprises flashing the second solvent component from the second solvent-wet tailings.

29. The method as recited in claim 23, wherein separating the bitumen-enriched solvent phase from the first mixture comprises filtering the first mixture in a plate and frame-type filter press.

30. The method as recited in claim 24, wherein separating the first solvent component from the first solvent-wet tailings comprises adding second solvent to the first solvent-wet tailings loaded in a plate and frame-type filter press.

31. The method as recited in claim 29, wherein filtering the first mixture in a plate and frame-type filter press further comprises adding a gas over the first mixture loaded in the plate and frame-type filter press.

32. The method as recited in claim 30, wherein gas is added over the first solvent-wet tailings loaded in the plate and frame-type filter press.

33. The method as claimed in claim 23, further comprising:

cracking the non-participating hydrocarbon inside a second nozzle reactor.

34. The method as claimed in claim 23, wherein the material comprising bitumen is tar sands.

35. The method as claimed in claim 23, wherein the first solvent comprises a light aromatic solvent.

36. The method as claimed in claim 35, wherein the light aromatic solvent comprises kerosene, diesel, gas oil, naphtha, benzene, toluene, an aromatic alcohol, derivatives thereof, or a combination thereof.

37. The method as claimed in claim 24, wherein the second solvent comprises a volatile hydrocarbon solvent.

38. The method as claimed in claim 37, wherein the volatile hydrocarbon solvent comprises a cyclo- or iso-paraffin having between 3 and 9 carbons, derivatives thereof, or combinations thereof.

39. The method as claimed in claim 24, wherein the second solvent is liquefied petroleum gas.

40. The method as claimed in claim 23, wherein the first nozzle reactor comprises:

an injection passage mounted in the nozzle reactor in material injecting communication with the injection end of the interior reactor chamber, the injection passage having (a) an enlarged volume injection section, an enlarged volume ejection section, and a reduced volume mid-section intermediate the enlarged volume injection section and enlarged volume ejection section, (b) a material injection end, and (c) a material ejection end in injecting communication with the interior reactor chamber;

a material feed passage penetrating the reactor body and being (a) adjacent to the material ejection end of the injection passage and (b) transverse to a injection passage axis extending from the material injection end to the material ejection end in the injection passage.

41. The method as claimed in claim 23, wherein the light hydrocarbon liquid distillate comprises hydrocarbon having a molecular weight less than 300 Daltons.

42. The method as claimed in claim 23, wherein cracking the asphaltene stream inside the first nozzle reactor comprises:

injecting a stream of cracking material through a injection passage into an interior reactor chamber; and

injecting the asphaltene stream into the interior reactor chamber adjacent to the injection passage and transverse to the stream of cracking material entering the interior reactor chamber from the injection passage.

43. The method as recited in claim 23, wherein separating the first solvent from the bitumen-enriched solvent phase comprises heating the bitumen-enriched solvent phase to a temperature above the boiling point temperature of the first solvent.

44. A method comprising:

solvent extracting a first quantity of material comprising bitumen with at least one solvent to separate bitumen from the first quantity of material comprising bitumen;

cracking the bitumen to form a light hydrocarbon liquid distillate; and

solvent extracting a second quantity of material comprising bitumen with the light hydrocarbon distillate to separate bitumen from the second quantity of material comprising bitumen.

45. A method comprising:

mixing a first solvent with a first quantity of material comprising bitumen;

separating a bitumen-enriched solvent phase from a first result of mixing the first solvent with the first quantity of material comprising bitumen;

feeding the bitumen-enriched solvent phase through a nozzle reactor; and

mixing a portion of a second result of feeding the bitumen-enriched solvent phase through a nozzle reactor with a second quantity of material comprising bitumen.

46. The method as recited in claim 45, wherein separating the bitumen-enriched solvent phase from the first result of mixing the first solvent with the first quantity of material comprising bitumen comprises:

filtering, settling or draining a first quantity of bitumen-enriched solvent phase from the first result of mixing the first solvent with the first quantity of material comprising bitumen;

displacing a second quantity of bitumen-enriched solvent phase from the first result of mixing the first solvent with the first quantity of material comprising bitumen.

47. The method as claimed in claim 45, wherein the first solvent comprises a light aromatic solvent.

48. The method as claimed in claim 45, wherein the portion of the second result comprises light hydrocarbon distillate.

49. A method comprising:

mixing a first quantity of material comprising bitumen with a first solvent;

separating a first solvent component from the bitumen-enriched solvent phase;

deasphalting a second result of separating the first solvent component from the bitumen-enriched solvent phase;

feeding a third result of deasphalting the second result into a nozzle reactor; and

mixing a portion of a fourth result of feeding the third result into a nozzle reactor with a second quantity of material comprising bitumen.

50. The method as claimed in claim 49, wherein the first solvent comprises a light aromatic solvent.

51. The method as claimed in claim 49, wherein the portion of the fourth result comprises light hydrocarbon distillate.

52. The method as claimed in claim 1, further comprising:

upgrading bitumen component of the bitumen-enriched solvent phase.

53. The method as claimed in claim 23, further comprising:

upgrading bitumen component of the bitumen-enriched solvent phase.