WO2015076786A1

WO2015076786A1 - Multi-pump systems for manufacturing hydraulic fracturing fluid

Info

Publication number: WO2015076786A1
Application number: PCT/US2013/070786
Authority: WO
Inventors: William Stewart; Brian PARR
Original assignee: Surefire Usa, Llc
Priority date: 2013-11-19
Filing date: 2013-11-19
Publication date: 2015-05-28

Abstract

Systems of producing viscous hydraulic fracturing fluids from the use of dry gels and liquids are disclosed involving multiple pumps which can generate said fluids and can supplement or replace each other when pumps fail or need assistance.

Description

MULTI-PUMP SYSTEMS FOR MANUFACTURING

HYDRAULIC FRACTURING FLUID

FIELD

[0001] The present disclosure relates to methods of manufacturing hydraulic fracturing fluid at a hydraulic fracturing site using a multiple pump system for mixing the hydraulic fluid.

BACKGROUND

[0002] Conventional or existing practice involves introduction of one or more additives to the formation independent of the fracturing operation. The additives are added at the production site either directly into the well bore or by mixing in a hopper or mixing equipment along with large volumes of the fracturing fluid, proppants and other substances needed in the fracturing operation. This results in inadequate dispersion of the additives in the fracturing fluid and the blend is not homogeneous. The process also does not allow for the monitoring and feedback needed to control the rate of addition of the additives to the fracturing fluids. The well operators, therefore, do not have control over the additive concentration delivered to the formation, or whether an effective amount of additives has been added, or whether too much additives have been added in the fracturing operation. This results in inadequate or excessive concentrations of additives being used in the frac or fracturing operation. This adversely impacts the fracturing operation, resulting in loss of production. Furthermore, large volumes of one or more fracturing fluids are required in the fracturing operation since adequate information on the composition, flow rates and/or interaction between the one or more fracturing fluids and the one or more additives is not easily available. The well operators typically employ larger than necessary fracturing volumes in an attempt to overcome this lack of information. All of this results in an inefficient and costly process. There is also an environmental cost associated to this, since the flowback fluids return from the well bore after the fracturing operation is completed and have to be cleaned up, and proper disposal of certain toxic additives comprising biocides and surfactants has to be ensured, at the end of the fracturing process. Embodiments of the invention teach an efficient and cost-effective method for the controlled delivery of fracturing fluids to the well bore. [0003] A hydraulic fracture is formed by pumping the fracturing fluid into the wellbore at a rate sufficient to increase pressure downhole at the target zone (determined by the location of the well casing perforations) to exceed that of the fracture gradient (pressure gradient) of the rock. Formation fluids include gas, oil, salt water and fluids introduced to the formation during completion of the well during fracturing.

[0004] Specialized fluid systems have been developed in the commercial fracking industry. These fluids are designed to implement a treatment according to design in order to help increase production and improve a return on investment. In general, the development of these fluid designs has been based on certain key parameters such as: fluid type, viscosity requirements, fluid rheology, cost, geologic formation type, material availability and proppant selection.

[0005] Fluid systems optimized to these parameters can result in minimized formation and fracture face damage for maximized results. In some instances, fluid systems are linear gels, cross-linked gels or friction-reduced water.

[0006] Linear gel fracturing fluids are typically formulated with a wide variety of different polymers in an aqueous base. Polymers that are commonly used to formulate these linear gels include guar, hydroxypropyl guar (HPG), carboxymethyl HPG, and hydroxyethyl cellulose. These polymers are dry powders that hydrate or swell when mixed with an aqueous solution and form a viscous gel.

[0007] Crosslinked gel fluids include such fluids as borate crosslinked fracturing fluids. Borate cross-linked fracturing fluids use borate ions to crosslink hydrated polymers and thereby increase viscosity. The polymers most often used in these fluids are HPG and guar. In the case of borate cross linking, the cross linking is reversible, thereby providing more effective cleanup.

[0008] Organometallic crosslinked fluids are another class of fracturing fluids often used in the industry. Particular fluids that are widely used include zirconate and titanate complexes of guar, HPG and carboxymethyl-hydroxypropyl guar. Organometallic crosslinked fluids are routinely used to transport the proppant for treatments in tight gas sand formations that require extended fracture lengths. [0009] Embodiments of the invention teach an efficient and cost-effective method for the controlled delivery of fracturing fluids to the well bore.

SUMMARY

[0010] Certain embodiments of the invention comprise a multiple pump system for creating a viscous hydraulic fracturing fluid. In such embodiments, the system comprises: a) an inlet manifold fluidly connected to a first bifurcated path comprising a first half fluidly connected to a second bifurcated path, the second bifurcated path being fluidly connected to a first pump and a second pump, and a second half comprising a first bypass outlet line upstream of and fluidly connected to a third pump; b) a hydration tank; c) a direct inflow line downstream of the first fluid pump and fluidly connecting the first fluid pump to the hydration tank; d) a second fluid path downstream of the second fluid pump and fluidly connecting the second fluid pump to a dry gel mixer, the dry gel mixer being downstream of and fluidly connected to the hydration tank; and e) a third bifurcated path downstream of the third fluid pump having one half fluidly connected to the direct inflow line downstream of the first fluid pump, and another half fluidly connected to a discharge manifold downstream of the third fluid pump.

[0011] In additional embodiments, the bypass outlet line has a valve. Valves of the system can be, but are not limited to butterfly valves Still further, in certain embodiments one half of the third bifurcated path fluidly connected to the direct inflow line has a third pump return line valve; and wherein the discharge manifold has one or more valves, and wherein the discharge manifold has one or more valves that when open, allow for discharge of fracturing fluid from the system.

[0012] In particular configurations of the system wherein: a) the bypass outlet line valve is closed; and b) the third pump return line valve is closed, fluid exits the hydration tank and the third fluid pump provides fluid pressure to increase the rate of fluid flow out of the discharge manifold relative to the third fluid pump not being used.

[0013] Other particular embodiments of the system include configurations wherein: a) the bypass outlet line valve is open; b) the direct inflow line valve is open; c) the discharge manifold has one or more valves closed to prevent discharge of fracturing fluid from the system; and wherein the third fluid pump pumps water from the inlet manifold, through the bypass outlet line and into the hydration tank through the direct inflow line. In such embodiments, when the third fluid pump is in use, the third fluid pump supplements or replaces the use of the first fluid pump in pumping fluid through the direct inflow line.

[0014] Still other particular embodiments of the system include configurations wherein: a) an upstream eductor line positioned downstream of the first fluid pump and upstream of the dry gel mixer and fluidly connecting the first fluid pump to the dry gel mixer; and b) a bypass line downstream of the second pump and fluidly connecting the direct inflow line to the upstream eductor line, the bypass line having a bypass valve.

[0015] In this embodiment, there are certain configurations wherein: a) the direct inflow line valve is open; b) the bypass line valve is open; c) the bypass outlet line valve is open; and d) the discharge manifold has one or more valves closed to prevent discharge of fracturing fluid from the system; the third fluid pump pumps water from the inlet manifold, through the bypass outlet line, through the bypass line and into both the dry gel mixer and into the hydration tank directly from the direct inflow line. In such embodiments, when the third fluid pump is in use, the third fluid pump supplements or replaces the use of the first fluid pump, supplements or replaces the use of the second fluid pump, or a combination thereof.

[0016] In this same embodiment, there are certain configurations wherein: a) the direct inflow line valve is open; b) the bypass line valve is open; c) the bypass outlet line valve is open; and d) the discharge manifold has one or more valves open to allow discharge of fracturing fluid from the system. In this configuration the third fluid pump pumps water from the inlet manifold, through the bypass outlet line, through the bypass line and into both the dry gel mixer and into the hydration tank directly from the direct inflow line. The result of this configuration is that the third fluid pump supplements or replaces the first fluid pump, supplements or replaces the second fluid pump, or a combination thereof, and wherein the the third fluid pump provides fluid pressure to increase the rate of fluid flow out of the discharge manifold relative to the third fluid pump not being used.

[0017] Other embodiments of the system pertain to the dry gel mixer. In certain embodiments the mixer is an eductor. In such embodiments, the dry gel used in the eductor is contained in a hopper operatively connected to the eductor. In particular embodiments, a conveyor moves the dry gel to the mixer wherein the gel is concentrated to form a concentrated gel

[0018] When the concentrated gel from the mixer enters the hydration tank and fluid from the hydration tank mixes with the concentrated gel, in certain embodiments, the mixing is via a shear baffle positioned within the hydration tank, a static mixer positioned within the hydration tank, a shear paddle positioned within the hydration tank or a combination thereof. In particular embodiments of the system concerning the dry gel, the dry gel is guar.

BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order that the manner in which the above-recited and other enhancements and objects of the invention are obtained, we briefly describe a more particular description of the invention briefly rendered by reference to specific embodiments thereof which are illustrated in the appended drawings. Understanding that these drawings depict only typical embodiments of the invention and are therefore not to be considered limiting of its scope, we herein describe the invention with additional specificity and detail through the use of the accompanying drawings in which:

[0020] Fig. 1 is schematic of the system of the present invention with two pumps;

[0021] Fig. 2 is a schematic of the system of the present invention with three pumps;

[0022] Fig. 3 is a shear baffle of the present invention;

[0023] Fig. 4 is a static mixer of the present invention;

[0024] Fig. 5 is a high shear paddle of the present invention; and

[0025] Fig. 6 is the implementation of the present invention on a tractor trailer.

List of Reference Numerals

[0026] 10 eductor line valve

[0027] 20 eductor [0028] 30 bypass valve

[0029] 40 bypass line

[0030] 50 direct inflow line

[0031] 60 hydration tank

[0032] 70 first pump

[0033] 75 first discharge valve

[0034] 80 metering device

[0035] 85 direct inflow line valve

[0036] 90 second pump

[0037] 95 second discharge valve

[0038] 100 upstream second pump flow line

[0039] 105 third discharge valve

[0040] 110 second pump valve

[0041] 115 third pump return line valve

[0042] 117 third pump return line

[0043] 120 upstream eductor line

[0044] 125 third pump inlet valve

[0045] 130 downstream eductor line

[0046] 140 hydration fluid valve

[0047] 150 outlet line valve [0048] 160 outlet line

[0049] 170 bypass outlet line

[0050] 180 first bypass outlet line valve

[0051] 190 second bypass outlet line valve

[0052] 195 discharge manifold

[0053] 200 inlet manifold

[0054] 210 viscosity meter

[0055] 230 hopper

[0056] 240 feed belt

[0057] 250 shear baffle

[0058] 260 static mixer

[0059] 265 educator nozzles

[0060] 270 high shear paddle

[0061] 280 trailer

DETAILED DESCRIPTION

[0062] Certain embodiments of the invention pertain to methods of premixing of a dry gel polymer and water at a well site to create a concentrated gel. Still further, certain embodiments of the invention pertain to methods of proper dilution of the concentrated gel with water to achieve the proper viscosity. In further embodiments of the invention, water is supplied to the concentrated gel with a plurality of pumps, such as three pumps or two pumps. In the alternative, if two pumps are broken or otherwise offline, then in certain embodiments one pump can be used. This is especially advantageous in real world operations as a substitute pump may not be readily available.

[0063] In certain embodiments, the viscosity of the gel is often determined in a hydration tank such that the concentration of concentrated gel to water is the correct concentration for the application. In certain further embodiments, water is routed to produce the concentrated gel and to produce the diluted gel in a dilution or displacement tank. In further embodiments, upon mixing the concentrated gel and the water to the desired concentration, the dilute gel is further mixed to add additional shear energy to the fluid.

[0064] In embodiments of the method concerning the preparation of concentrated gel, in certain embodiments, the dry gel is guar or a complex of guar such as hydroxypropyl guar (HPG), carboxymethyl HPG or a combination thereof. In embodiments concerning the liquid to be mixed with the dry gel, the liquid is water, ammonia, methanol, ethanol, gasoline, diesel, mineral oil, any liquid organic compound and the like. In specific embodiments, the liquid is water.

[0065] In embodiments of the method concerning the preparation of concentrated gel, in certain embodiments, the dry gel is dispersed by a container into a liquid medium in order to produce a concentrated gel from the dry gel. In further embodiments, the container is a barrel, a cylinder, a box, a hopper and the like. In specific embodiments, the container is a hopper.

[0066] In further embodiments, the container is operatively attached to a mechanism to move the dry gel from the container to the liquid medium in order to produce a concentrated gel. In such embodiments, the mechanism is a valve, a conveyor belt, a vacuum suction, a piston to push the dry gel, a blower to push the dry gel, or a combination thereof. In specific embodiments, the mechanism to move the dry gel from the container to the liquid medium is a conveyor belt. In further embodiments, in lieu of a conveyor belt, the metering apparatus for chemicals such as guar or other hydraulic fracturing dry gel can be an auger feeder "acrison", a fixed screw feeder "olds elevator", a pneumatic conveyor (such as pressurized and non-pressurized blowing, a mechanical feeder such as a train driven trough and a vibrating conveyor. [0067] Further embodiments of the invention concern the mixing of the dry gel with the liquid medium. In such instances, the mixing of the dry gel with the liquid medium is performed by pouring the dry gel into the liquid, by sprinkling the dry gel into the liquid, by stirring the dry gel into the liquid, by spraying the dry gel into the liquid, by pouring the liquid onto the dry gel, by spraying the liquid onto the dry gel, by pumping the dry gel into the liquid, by using an eductor to mix the dry gel with the liquid, or a combination thereof. In such embodiments, the mixing of the dry gel with the liquid created a concentrated gel with a high viscosity.

[0068] Additional embodiments of the invention pertain to mixing the concentrated gel with further liquid to generate a correctly viscous liquid capable of being used in hydraulic fracturing operations. In such embodiments, the concentrated gel is pumped or pushed through pressure into a hydration tank. They hydration tank, in certain embodiments, already contains a liquid. In other embodiments, the concentrated gel is pumped into the hydration tank and then the liquid is pumped into the hydration tank. In still other embodiments, the concentrated gel is pumped into the hydration tank at the same time as the liquid.

[0069] In embodiments wherein the concentrated gel is diluted in the hydration tank, the concentrated gel and liquid are mixed to add additional shear energy to the fluid. In certain embodiments, the mixing is accomplished by one or more shear baffle. In certain embodiments, the mixing is accomplished by one or more static mixer. In certain further embodiments, the mixing is accomplished by one or more high shear paddles. In still further embodiments, the mixing is accomplished by some combination of the aforementioned methods.

[0070] In embodiments concerning the static mixer, the concentrated gel is diluted down with liquid in the hydration tank using a static mixing system. The static mixer creates a tremendous amount of shear on the fluid. In certain embodiments, the static mixer is composed of a plurality of eductor nozzles capable of pulling concentrated gel in using the velocity of the liquid through a restricted orifice. In certain further embodiments, a poppet type valve is built into the bottom of the static mixer to create back pressure on the nozzles which can be used to create high velocity mixing.

[0071] In embodiments concerning the high shear paddles, in certain embodiments, the paddles create a very high amount of mechanical shear on the fluid at very low speeds, for example, but not limited to 30 rpm. In such embodiments, this reduces splashing and maximizes the amount of shear while moving the fluid as little as possible. Traditional paddle designs create shear by generating bulk motion of the fluid and creating turbulence. This requires a tremendous amount of horsepower per the amount of shear. By creating localized mechanical shear around the edges of the holes in the high shear paddle, mixing can be enhanced with the usage of less horsepower.

[0072] Regarding the entry of liquid into the system to create the concentrated gel and the diluted gel, the liquid enters the process through an inlet manifold. The system comprises pipes to move liquid and gel from one location to another. The pipes are of any diameter necessary to produce the necessary amount of dilute gel for hydraulic fracturing operations. For instance, the pipes can have an internal diameter of 1 inch to three feet or some derivation therein. However, the diameter is not limited to this range.

[0073] Certain further embodiments of the invention overcome potential problems with high rates of on-site hydraulic fracturing fluid production. In certain embodiments, a multiple pump system replaces a single pump system. In embodiments wherein there is a single pump system, a limiting factor is that the hydration tank should have a set amount of hydraulic fracturing fluid set by the operator. In such embodiments, when the operator us using as much water as can be put into the tank, the valve from the pump to the hydration tank is opened to maximum to maintain the level inside the tank.

[0074] In such embodiments, wherein there is only one pump and the valve from the pump to the hydration tank is open, proper mixing of dry gel in the eductor can arise. In such embodiments, the water destined for the hydration tank starves the flow of water the eductor, thereby puling excess dry gel into the system without proper hydration. In such embodiments, the system becomes plugged with dry gel which has not been properly hydrated.

[0075] In embodiments of the method concerning the preparation of concentrated gel, in certain embodiments, the dry gel is guar or a complex of guar such as hydroxypropyl guar (HPG), carboxymethyl HPG or a combination thereof. In embodiments concerning the liquid to be mixed with the dry gel, the liquid is water, ammonia, methanol, ethanol, gasoline, diesel, mineral oil, any liquid organic compound and the like. In specific embodiments, the liquid is water. [0076] In embodiments of the method concerning the preparation of concentrated gel, in certain embodiments, the dry gel is dispersed by a container into a liquid medium in order to produce a concentrated gel from the dry gel. In further embodiments, the container is a barrel, a cylinder, a box, a hopper and the like. In specific embodiments, the container is a hopper.

[0077] In further embodiments, the container is operatively attached to a mechanism to move the dry gel from the container to the liquid medium in order to produce a concentrated gel. In such embodiments, the mechanism is a valve, a conveyor belt, a vacuum suction, a piston to push the dry gel, a blower to push the dry gel, or a combination thereof. In specific embodiments, the mechanism to move the dry gel from the container to the liquid medium is a conveyor belt. In further embodiments, in lieu of a conveyor belt, the metering apparatus for chemicals such as guar or other hydraulic fracturing dry gel can be an auger feeder "acrison", a fixed screw feeder "olds elevator", a pneumatic conveyor (such as pressurized and non-pressurized blowing, a mechanical feeder such as a train driven trough and a vibrating conveyor.

[0078] Further embodiments of the invention concern the mixing of the dry gel with the liquid medium. In such instances, the mixing of the dry gel with the liquid medium is performed by pouring the dry gel into the liquid, by sprinkling the dry gel into the liquid, by stirring the dry gel into the liquid, by spraying the dry gel into the liquid, by pouring the liquid onto the dry gel, by spraying the liquid onto the dry gel, by pumping the dry gel into the liquid, by using an eductor to mix the dry gel with the liquid, or a combination thereof. In such embodiments, the mixing of the dry gel with the liquid created a concentrated gel with a high viscosity.

[0079] Additional embodiments of the invention pertain to mixing the concentrated gel with further liquid to generate a correctly viscous liquid capable of being used in hydraulic fracturing operations. In such embodiments, the concentrated gel is pumped or pushed through pressure into a hydration tank. They hydration tank, in certain embodiments, already contains a liquid. In other embodiments, the concentrated gel is pumped into the hydration tank and then the liquid is pumped into the hydration tank. In still other embodiments, the concentrated gel is pumped into the hydration tank at the same time as the liquid.

[0080] In embodiments wherein the concentrated gel is diluted in the hydration tank, the concentrated gel and liquid are mixed to add additional shear energy to the fluid. In certain embodiments, the mixing is accomplished by one or more shear baffle. In certain embodiments, the mixing is accomplished by one or more static mixer. In certain further embodiments, the mixing is accomplished by one or more high shear paddles. In still further embodiments, the mixing is accomplished by some combination of the aforementioned methods.

[0081] In embodiments concerning the static mixer, the concentrated gel is diluted down with liquid in the hydration tank using a static mixing system. The static mixer creates a tremendous amount of shear on the fluid. In certain embodiments, the static mixer is composed of a plurality of eductor nozzles capable of pulling concentrated gel in using the velocity of the liquid through a restricted orifice. In certain further embodiments, a poppet type valve is built into the bottom of the static mixer to create back pressure on the nozzles which can be used to create high velocity mixing.

[0082] In embodiments concerning the high shear paddles, in certain embodiments, the paddles create a very high amount of mechanical shear on the fluid at very low speeds (30 rpm). In such embodiments, this reduces splashing and maximizes the amount of shear while moving the fluid as little as possible. Traditional paddle designs create shear by generating bulk motion of the fluid and creating turbulence. This requires a tremendous amount of horsepower per the amount of shear. By creating localized mechanical shear around the edges of the holes in the high shear paddle, mixing can be enhanced with the usage of less horsepower.

[0083] Regarding the entry of liquid into the system to create the concentrated gel and the diluted gel, the liquid enters the process through an inlet manifold. The system comprises pipes to move liquid and gel from one location to another. The pipes are of any diameter necessary to produce the necessary amount of dilute gel for hydraulic fracturing operations. For instance, the pipes can have an internal diameter of 1 inch to three feet or some derivation therein. However, the diameter is not limited to this range.

[0084] Certain embodiments concern a liquid path bifurcation also known as a bypass line, the bifurcation allows liquid to flow into the hydration tank the eductor, or both the hydration tank and the eductor. In further embodiments, the eductor is positioned downstream of the bifurcation and upstream of the hydration tank. [0085] To control the flow of liquid coming from the liquid path bifurcation, valves are used. In certain embodiments, the valves can be annular valves, diaphragm valves, fixed cone valves, gate valves, needle valves, pinch valves, ball valves, butterfly valves, plug valves and the like. In specific embodiments, the valves are butterfly valves.

[0086] In embodiments the multiple pump system is a two pump system.

[0087] In further embodiments of the invention, wherein a three pump system is employed, the three pump process has an added advantage of a way of discharging the viscous gel from the hydration tank at a higher pressure and at a higher flow rate than if not.

[0088] In certain embodiments, wherein a high level of hydraulic fracturing fluid must be produced in a short time, the embodiments of the invention alleviate this potential problem by providing adequate hydration to the eductor by employing three pump configuration is to control the amount of water going to the eductor or optionally out of the discharge manifold to provide a higher pressure or a higher volume delivery to the fracking operation.

[0089] In other embodiments, wherein the viscous fracturing fluid is not viscous enough for fracturing operations, the first, second and third discharge manifold valves are shut off and a third pump return line valve is opened. Also the third pump inlet valve is opened and both the first bypass outlet line valve and the second bypass outlet line valve are closed.

[0090] In such embodiments when the third pump return line valve is opened, the less than desirable viscous fluid can flow up the third pump return line, into the direct inflow line, past the direct inflow line valve, past the bypass valve and into the upstream eductor line. Upon reaching the upstream eductor line, the fluid that has less than a desired viscosity is able to enter the eductor or other mixing device wherein it is mixed with a dry gel such as guar. Upon mixing, the more viscous fluid flows through the downstream eductor line, through the eductor line valve and into the hydration tank.

[0091] As another option, should the either of the first pump or the second pump fail, the third pump can substitute for the first pump, second pump, or both thereby providing redundancy. In such embodiments, water or another diluent can flow from the inlet manifold, into the bypass outline line, through an open first bypass line valve and into the third pump when the third pump inlet valve is open. In this embodiment wherein the third pump is functioning, the first, second and third discharge manifold pumps are closed. The first bypass outlet line is open and the second bypass outlet line is closed. Thus, water or other diluent flows into the third pump. Upon reaching the third pump, the pump is able to move the water or other diluent past the opened third pump line valve, through the direct inflow line, past the direct inflow line valve and through the open bypass valve. In such embodiments, the third pump is able to take the place of either or both of the first and second pump and is able to pump water or diluent into the upstream eductor line, into the eductor, wherein the water or diluent is mixed with a dry gel, through the downstream eductor line, past the eductor line valve and into the hydration tank.

[0092] Also in this embodiment, since the direct inflow line valve is open, water or other diluent will be able to bypass the eductor and flow directly into the hydration tank via an open hydration tank fluid valve.

[0093] In still further embodiments, to prevent any further damage to a broken pump, or to prevent backflow to a broken pump when the third pump is in operation, a first pump inlet valve is able to prevent flow to or from the first pump when closed. Likewise, a second pump inlet valve is able to prevent flow to or from the second pump when closed. When both the first pump inlet valve and the second pump inlet valve are closed, circulation within the system is controlled by the third pump.

[0094] In embodiments wherein the either or both the first pump and the second pump are offline or otherwise broken, the third pump, in certain embodiments, can be run at higher speeds to compensate for the amount of flow of fluid going through the eductor and fluid going directly into the hydration tank.

[0095] In other embodiments, wherein either or both the first pump and the second pump are offline or otherwise broken, the third pump is run at normal speeds, which will decrease the flow through the eductor and the flow directly into the hydration tank.

[0096] In certain further embodiments wherein only the second pump is broken or otherwise offline, the first pump and the third pump can compensate for the second pump. In such embodiments, the third pump inlet valve is open as well as the first bypass outlet line valve. The direct inflow line valve is open, the second bypass outlet line valve is closed and the bypass valve is open. Additionally the second pump inlet valve is closed. In this embodiment, water or other diluent flows into both the first and third pumps, wherein both pumps supply water or other diluent to the eductor or other mixer type that mixes the dry gel with the liquid. Additionally, the first and third pumps supply water or other diluent to the hydration tank through the hydration fluid valve.

[0097] In certain further embodiments wherein only the first pump is broken or otherwise offline, the second pump and the third pump can compensate for the first pump. In such embodiments, the third pump inlet valve is open as well as the first bypass outlet line valve. The direct inflow line valve is open, the second bypass outlet line valve is closed and the bypass valve is open. Additionally the first pump inlet valve is closed. In this embodiment, water or other diluent flows into both the second and third pumps, wherein both pumps supply water or other diluent to the eductor or other mixer type that mixes the dry gel with the liquid. Additionally, the second and third pumps supply water or other diluent to the hydration tank through the hydration fluid valve.

[0098] As seen in Fig. 1, the valves are placed in the system wherever control or shutoff of the liquid or gel is desired. In certain embodiments, an eductor line valve 10, is positioned downstream of the eductor 30 so as to prevent concentrated gel from entering the hydration tank. This allows fluid without concentrated gel to flow into the hydration tank.

[0099] In other embodiments, wherein a high amount of hydraulic fracturing fluid is desired, a bypass valve 30 is positioned downstream of the bypass line 40, and is closed such that the first pump 70, through the metering device 80, and through the direct inflow line valve 85 pushes liquid into direct inflow line 50 and into to the hydration tank 60. Additionally, the second pump 90, pumps fluid from the upstream second pump flow line 100, through the second pump 90, past the second pump valve 110, through the upstream eductor line 120, and into the eductor 20. Subsequently, the second pump pumps concentrated hydraulic fluid gel into the hydration tank 60 through the downstream eductor line 130 and into the hydration tank 60 when the eductor line valve 10 is open. In this embodiment, the outlet line valve 150 of the outlet line 160 is opened to supply hydraulic fracturing fluid for operations, while the bypass outlet line 170, the first bypass outlet line valve 180 and the second bypass outlet line valve 190 are closed.

[00100] In embodiments wherein a lower amount of hydraulic fracturing fluid is desired, the second pump 90 is shut off and additively or optionally, the second pump valve 110 is closed. In this embodiment, the bypass valve 30 is opened, and the first pump 70 pumps fluid both through the eductor 20, the downstream eductor line 130 and into the hydration tank 60, while at the same time pumping fluid through the direct inflow line valve 85, the direct inflow line 50 and into the hydration tank, past the hydration fluid valve 140. In this embodiment, the outlet line valve 150 of the outlet line 160 is opened to supply hydraulic fracturing fluid for operations, while the bypass outlet line 170, the first bypass outlet line valve 180 and the second bypass outlet line valve 190 are closed. This configuration also works if the second pump 90 is broken.

[00101] In still further embodiments, wherein the viscosity of the hydraulic fracturing fluid is too low in the hydration tank, another configuration is employed. In this embodiment, the outlet line valve 150 of the outlet line 160 is opened and the discharge manifold 195 is closed. The bypass outlet line 170, the first bypass outlet line valve 180 is opened, and the second bypass outlet line valve 190 is optionally opened and the inlet manifold 200 is closed. In this configuration, the bypass valve 30 is closed, the direct inflow line valve 85 is open and the second pump valve 110 is open. This allows the first pump 70 to supply the lower viscosity hydraulic fluid to the hydration tank 60, through the open hydration fluid valve 140, while the second pump 90 pushes the same fluid through the open second pump valve 110, through the upstream eductor line 120, the eductor 20 the downstream eductor line 130 and into the hydration tank 60 through the eductor line valve 10.

[00102] In embodiments wherein the first pump 70 is broken, the outlet line valve 150 of the outlet line 160 is opened to supply hydraulic fracturing fluid for operations, while the bypass outlet line 170, the first bypass outlet line valve 180 and the second bypass outlet line valve 190 are closed. In this embodiment, fluid is pumped through the second pump 90, through the second pump valve 110, and through the bypass line 40. Further, the bypass valve 30 is opened. Consequently, fluid is pushed through the upstream eductor line 120, the eductor 20 the downstream eductor line 130 and into the hydration tank 60 through the eductor line valve 10. Fluid is also pushed through the direct inflow line valve 85, through the direct inflow line 50 and into the hydration tank 60 and out the opened hydration fluid valve 140.

[00103] In certain further embodiments, the viscosity of the diluted gel within the hydration tank is measured to determine if it is the correct viscosity for the fracturing operation. In such embodiments, the viscosity meter 210 is within the hydration tank 60 or fluidly connected to the hydration tank 60. Additionally as can be seen, a hopper 230 supplies the dry gel to the eductor through a feed belt 240.

[00104] As seen in Fig. 2, wherein a three pump system is employed, the three pump process has an added advantage of a way of discharging the viscous gel from the hydration tank at a higher pressure and at a higher flow rate than if not.

[00105] In the three pump configuration the discharge manifold 195 provides a higher pressure or a higher volume delivery to the fracking operation.

[00106] In other embodiments, wherein the viscous fracturing fluid is not viscous enough for fracturing operations, the first 75, second 95 and third 105 discharge manifold valves are shut off and a third pump return line valve 115 is opened. Also the third pump inlet valve 125 is opened and both the first bypass outlet line valve 180 and the second bypass outlet line valve 190 are closed.

[00107] In such embodiments when the third pump return line valve 115 is opened, the less than desirable viscous fluid can flow up the third pump return line 117, into the direct inflow line 85, past the direct inflow line valve 85, past the bypass valve 30 and into the upstream eductor line 120. Upon reaching the upstream eductor line 120, the fluid that has less than a desired viscosity is able to enter the eductor 20 or other mixing device wherein it is mixed with a dry gel such as guar. Upon mixing, the more viscous fluid flows through the downstream eductor line 130, through the eductor line valve 10 and into the hydration tank 60.

[00108] As another option, should the either of the first pump 70 or the second pump fail 90, the third pump 135 can substitute for the first pump 70, second pump 90, or both thereby providing redundancy. In such embodiments, water or another diluent can flow from the inlet manifold 200, into the bypass outline line 170, through an open first bypass line valve 180 and into the third pump 130 when the third pump inlet valve 125 is open. In this embodiment wherein the third pump 135 is functioning, the first 75, second 95 and third discharge 105 manifold pumps are closed. The first bypass outlet line valve is open 180 and the second bypass outlet line valve 190 is closed. Thus, water or other diluent flows into the third pump 135. Upon reaching the third pump 135, the pump is able to move the water or other diluent past the opened third pump return line valve 115, through the direct inflow line 50, past the direct inflow line valve 85 and through the open bypass valve 30. In such embodiments, the third pump 135 is able to take the place of either or both of the first 70 and second 90 pump and is able to pump water or diluent into the upstream eductor line 120, into the eductor 20, wherein the water or diluent is mixed with a dry gel, through the downstream eductor line 130, past the eductor line valve 10 and into the hydration tank 60.

[00109] Also in this embodiment, since the direct inflow line valve 85 is open, water or other diluent will be able to bypass the eductor 20 and flow directly into the hydration tank 60 via an open hydration tank fluid valve 140.

[00110] In still further embodiments, to prevent any further damage to a broken pump, or to prevent backflow to a broken pump when the third pump 135 is in operation, a first pump inlet valve 145 is able to prevent flow to or from the first pump 70 when closed. Likewise, a second pump inlet valve 155 is able to prevent flow to or from the second pump 90 when closed. When both the first pump inlet valve 145 and the second pump inlet valve 155 are closed, circulation within the system is controlled by the third pump 135.

[00111] In certain further embodiments wherein only the second pump 90 is broken or otherwise offline, the first pump 70 and the third pump 135 can compensate for the second pump 90. In such embodiments, the third pump inlet valve 125 is open as well as the first bypass outlet line valve 180. The direct inflow line valve is open 85, the second bypass outlet line valve 190 is closed and the bypass valve 30 is open. Additionally the second pump inlet valve 155 is closed. In this embodiment, water or other diluent flows into both the first 90 and third pumps 135, wherein both pumps supply water or other diluent to the eductor 20 or other mixer type that mixes the dry gel with the liquid. Additionally, the first70 and third pumps 135 supply water or other diluent to the hydration tank through the hydration fluid valve 140. [00112] In certain further embodiments wherein only the first pump 70 is broken or otherwise offline, the second pump 90 and the third pump 135 can compensate for the first pump 70. In such embodiments, the third pump inlet valve 125 is open as well as the first bypass outlet line valve 180. The direct inflow line valve 85 is open, the second bypass outlet line valve 190 is closed and the bypass valve 30 is open. Additionally the first pump inlet valve 145 is closed. In this embodiment, water or other diluent flows into both the second 90 and third pumps 135, wherein both pumps supply water or other diluent to the eductor 20 or other mixer type that mixes the dry gel with the liquid. Additionally, the second 90 and third pumps 135 supply water or other diluent to the hydration tank through the hydration fluid valve 140.

[00113] As can further be seen in Fig. 2, the metering device 80 can be positioned directly upstream of the inlet manifold 200.

[00114] As can be seen in Fig. 3 is shear baffle 250 of the present invention. The shear baffle sits within the hydration tank 60 such that the liquid and concentrated gel passes through the baffle to better mix the two together.

[00115] Fig. 4 illustrates the static mixer 260 found in the hydration tank 60. The static mixer possesses educator nozzles 265 that pull concentrated gel in using the velocity of the fresh water or liquid through a restricted orifice.

[00116] Fig. 5 illustrates the high shear paddle 270 of the present invention. The paddle is situated within the hydration tank 60 and is designed to create a high amount of mechanical shear on the fluid at very low speeds. The shear baffle 250, the static mixer 260 and the high shear paddle 270 of the present invention can be found in the hydration tank 60 as shown on a trailer 280 in Figs. 4, 5 and 6 respectively.

[00117] From the foregoing description, one of ordinary skill in the art can easily ascertain the essential characteristics of this disclosure, and without departing from the spirit and scope thereof, can make various changes and modifications to adapt the disclosure to various usages and conditions. For example, we do not mean for references such as above, below, left, right, and the like to be limiting but rather as a guide for orientation of the referenced element to another element. A person of skill in the art should understand that certain of the above-described structures, functions, and operations of the above-described embodiments are not necessary to practice the present disclosure and are included in the description simply for completeness of an exemplary embodiment or embodiments. In addition, a person of skill in the art should understand that specific structures, functions, and operations set forth in the above-described referenced patents and publications can be practiced in conjunction with the present disclosure, but they are not essential to its practice.

[00118] The invention can be embodied in other specific forms without departing from its spirit or essential characteristics. A person of skill in the art should consider the described embodiments in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. A person of skill in the art should embrace, within their scope, all changes to the claims which come within the meaning and range of equivalency of the claims. Further, we hereby incorporate by reference, as if presented in their entirety, all published documents, patents, and applications mentioned herein.

Claims

CLAIMS We claim:

1. A multiple pump system for creating a viscous hydraulic fracturing fluid, the system comprising

a) an inlet manifold fluidly connected to a first bifurcated path comprising a first half fluidly connected to a second bifurcated path, the second bifurcated path being fluidly connected to a first pump and a second pump, and a second half comprising a first bypass outlet line upstream of and fluidly connected to a third pump;

b) a hydration tank;

c) a direct inflow line downstream of the first fluid pump and fluidly connecting the first fluid pump to the hydration tank;

d) a second fluid path downstream of the second fluid pump and fluidly connecting the second fluid pump to a dry gel mixer, the dry gel mixer being downstream of and fluidly connected to the hydration tank; and

e) a third bifurcated path downstream of the third fluid pump having one half fluidly connected to the direct inflow line downstream of the first fluid pump, and another half fluidly connected to a discharge manifold downstream of the third fluid pump.

2. The system of claim 1, wherein:

a) the bypass outlet line has a valve;

b) one half of the third bifurcated path fluidly connected to the direct inflow line has a third pump return line valve; and

wherein the discharge manifold has one or more valves, and wherein the discharge manifold has one or more valves that when open, allow for discharge of fracturing fluid from the system.

3. The system of claim 2, wherein:

a) the bypass outlet line valve is closed;

b) the third pump return line valve is closed; and wherein fluid exits the hydration tank and the third fluid pump provides fluid pressure to increase the rate of fluid flow out of the discharge manifold relative to the third fluid pump not being used.

4. The system of claim 2, wherein:

a) the bypass outlet line valve is open;

b) the direct inflow line valve is open;

c) the discharge manifold has one or more valves closed to prevent discharge of fracturing fluid from the system; and

wherein the third fluid pump pumps water from the inlet manifold, through the bypass outlet line and into the hydration tank through the direct inflow line.

5. The system of claim 4, wherein when the third fluid pump is in use, the third fluid pump supplements or replaces the use of the first fluid pump in pumping fluid through the direct inflow line.

5. The system of claim 2, further comprising:

a) an upstream eductor line positioned downstream of the first fluid pump and upstream of the dry gel mixer and fluidly connecting the first fluid pump to the dry gel mixer; and b) a bypass line downstream of the second pump and fluidly connecting the direct inflow line to the upstream eductor line, the bypass line having a bypass valve.

6. The system of claim 5, wherein:

a) the direct inflow line valve is open;

b) the bypass line valve is open;

c) the bypass outlet line valve is open;

d) the discharge manifold has one or more valves closed to prevent discharge of fracturing fluid from the system; and

wherein the third fluid pump pumps water from the inlet manifold, through the bypass outlet line, through the bypass line and into both the dry gel mixer and into the hydration tank directly from the direct inflow line.

7. The system of claim 6, when the third fluid pump is in use, the third fluid pump

supplements or replaces the use of the first fluid pump, supplements or replaces the use of the second fluid pump, or a combination thereof.

8. The system of claim 5, wherein:

a) the direct inflow line valve is open;

b) the bypass line valve is open;

c) the bypass outlet line valve is open;

d) the discharge manifold has one or more valves open to allow discharge of fracturing fluid from the system; and

9. The system of claim 8, wherein the third fluid pump supplements or replaces the first fluid pump, supplements or replaces the second fluid pump, or a combination thereof, and wherein the the third fluid pump provides fluid pressure to increase the rate of fluid flow out of the discharge manifold relative to the third fluid pump not being used.

10. The system of claim 1, wherein the mixer is an eductor.

11. The system of claim 1, wherein the dry gel is contained in a hopper operatively connected to the mixer.

12. The system of claim 1, wherein a conveyor moves the dry gel to the mixer to create a concentrated gel.

13. The system of claim 12, wherein the concentrated gel and the fluid in the hydration tank are mixed into a viscous hydraulic fracturing gel by a shear baffle positioned within the hydration tank.

14. The system of claim 12, wherein the concentrated gel and the fluid in the hydration tank are mixed into a viscous hydraulic fracturing gel by a static mixer positioned within the hydration tank.

15. The system of claim 12, wherein the concentrated gel and the fluid in the hydration tank are mixed into a viscous hydraulic fracturing gel by a shear paddle positioned within the hydration tank.

16. The system of claim 1, wherein the valves are butterfly valves. 18. The system of claim 1, wherein the dry gel is guar.