US2606861A

US2606861A - Hydrocarbon conversion process

Info

Publication number: US2606861A
Application number: US80583A
Authority: US
Inventors: Sylvander C Eastwood
Original assignee: Socony Vacuum Oil Co Inc
Current assignee: ExxonMobil Oil Corp
Priority date: 1949-03-10
Filing date: 1949-03-10
Publication date: 1952-08-12
Anticipated expiration: 1969-08-12

Description

Aug. 12, 1952 s. c. EASTWOOD HYDROCARBON CONVERSION PROCESS Filed March 10, 1949 FLUE as our 22 W Lu] T L HI HEATER I 24 0001.51? 5 HIM. l/V 2/ 23 A/fifi r /4 FLUID 11v STEAM STEAM 5 SEAL CHAMBER SEAL v 55 cmuam- REDUCED 29 it" anuos FEED 30 5 Sheets-Sheet 1 F/G. I

aorivsron HEATER GATAL YT/C CRACK/N6 SYSTEM 1 CRACKED PRODUCT OUT INVENTOR. 5H. VA/VDER 6. EASTWOOD AGA/T 0R ATTORNEY Aug. 12, 1952 s. c. EASTWOOD HYDROCARBON CONVERSION PROCESS 5 Sheets-Sheet 2 FIG. 2

Filed March 10, 1949 COOLE/V 0 D T 5 E 0 M 0 5 WM MN /V E 9 U YL R E NA/ PT L/ o N T F S K T a A0 NM R R 6T WE m m r R A al E f w 0 m T m v r N. v! M E 3 f m w w 6 w A o R M [M m J Mu r 07 8 Aug. 12, 1952 s, c, EASTWOOD 2,606,861

HYDROCARBON CONVERSION PROCESS Filed March 10, 1949 3 Sheetg-Sheet 3 77 5 F/POM warm 4 STE/7M 197 INVENTOR. f/Lkfl/VDEI? (3 457 W001) Patented Aug. 12,. 1952 I 2,606,861 HYDROCARBON ooNvERsioN PRQCESS- Sylvander C. Eastwood, Woodbury, N. J .,.assignor to Socony-Vacuum Oil Company, Incorporated, a corporation of New York 7 Application March 10, 1949, Serial No. 80,583

This invention pertains to the conversion of high boiling hydrocarbons tovaluable lower boiling products. It is particularly concerned with a process for the cracking conversion in the presence of solid contact mass materials of high boiling liquid petroleum fractions which undergo thermal decomposition below temperatures at which they will vaporize.

It is well known that vaporized petroleum gas oils and the like may be converted to lower boiling products containing high antiknock-gasoline by contacting the gas oil with adsorbent catalysts at temperatures of the order of about'8 F. and upwards and pressures usually of the order of 5 to .100 pounds per square inchgauge. It is also known to similarly convert higher boiling petroleum fractions which exist in the liquid phase under the cracking conditions. However, in the latter case, the amount of coky material deposited on the catalyst during the cracking reaction is very high, particularly in the case of stocks having high carbon residues such as petroleum residuums. In many cases the amount of coke deposit on the catalyst, which must be removed by burning in order to maintain the catalyst activity is so high as to render the catalytic cracking of petroleum residue charges economically unfeasible. It is usually the practice to subject such petroleum residuums to a preliminary coking, tar separation or viscosity reducing treatment prior to use as a catalytic cracking charge stock. Often even in these operations, the gasiform stream from the coking vessel, for example contains substantial amounts of entrained liquid hydrocarbons having a very high carbon residue content. These streams cause serious coking on the walls of the coking vessel near the gas outlets and in the transfer lines leaving the coking unit and also in any heating furnace through which they may pass prior to introduction into a catalytic cracking reactor. Also, the entrained liquid in the gasiform stream from the coking unit may result in undesirable heavy coke deposits on the cracking catalyst thereby largely defeating the purpose of the coking or tar separation operation.

It is a major object of this invention to provide an improved process whereby high boiling liquid petroleum fractions may be converted to high antiknock gasolines while avoiding the above mentioned difficulties.

Another object of this invention is the provision of an improved process for conducting coking conversions of petroleum residuums to provide lower boiling vaporizable products having low carbon residue contents.

11 Claims. (01. 196-52) 2 ,Aspecific object is the provisionof a ,novel continuous .processfor pyrolytically and catalytically, converting petroleum residuums and the like to gasoline containing productsin the presence of suitable solid contact materials. These and other objects of this invention will become apparent from the following description thereof.

This invention inits preferred form involves a method wherein the high boiling liquid hydrocarbon charge, for example apetroleum residuum is introduced into the lower section. of a compact column of granular inertsheat carrying material to become converted pyrolytically to a gasiform intermediate product which may contain small amounts of entrained non-vaporized liquid hydrocarbons. The intermediate product is then passed upwardly through the column until it contacts cooler heatcarrying material'by which it is quenchedto a temperature at which the pyrolytic reaction is substantially inhibited and the entrained liquid is deposited'onto the heat carrying material. In some operations, a small percentage of the intermediate product may be condensed and also deposited u'ponthe contact material. The deposited liquid subsequently breaks down to cokeand gasiform product in the lower portion of the column. The cooled gasiform intermediate product substantially free of entrained liquid hydrocarbons is then heated toa suitable catalytic cracking temperature and passed into contact with a suitable adsorbent catalyst to. effect its conversion to a product containing high antiknock gasoline. A stream of heated inert heat carrying material is passed from a separate heater into the lower section of the column to supply the heat required for the pyrolytic conversion of the liquid hydrocarbon charge. A second stream of the same heat carrying material is supplied to the column at a higher level than the first stream and at .a lower ,temperature so as to effect the quenching of the intermediate reaction product. According to one form of this invention, a third stream of heat carrying material is supplied to thecolumn at a still higher level and at a temperature interme-v diate those of the first and second streams to efiect heating by direct heat exchange .of the quenched intermediate product to the catalytic cracking temperature. Used heat carrying material is withdrawn from the bottom of the column to cause downward movement of the granular material in the column.

The inert granular material employed in the process of this invention should be .a solidmaterial having a relatively low orsubstantially no catalytic cracking activity, a high heat absorption capacity and it should be capable of withstanding high temperatures of the order of 1500 F. without severe breakage, cracking or attrition. The material may be non-porous, for example metallic pieces or balls. Preferably however, the solid material should be porous, for example natural clays which have become deactivated so as to have a very low activity as a cracking catalyst. Other materials which may be employed are pumice, mullite, fused alumina, silica, etc. A preferred heat carrying material is granular petroleum coke. The granular material may range in size from about 100 mesh Tyler up to about one inch in diameter and preferably of the order of one-eighth to one-quarter inch diameter. The term granular is employed herein in a broad sense as including solids in various shapes and forms such as pellets, tablets, spheres and irregular shaped particles.

The catalyst employed for the final catalytic cracking step maypartake of the nature of natural or treated clays, bauxites and the like or synthetic associations of silica, alumina, magnesia or silica and alumina or silica and magnesia to which other metallic oxidesv may be added for special purposes- The catalyst may be in the form of a powder in which event it may be maintained in suspension in the reaction zone. On the other hand, the catalyst may preferably be in the form of granular particles having average diameters within the range about 4 to 100 mesh Tylerand preferably 4 to 20 mesh.

The invention may be more readily understood by reference to the attached drawings of which Figure 1 is an elevational View, partially in section, of one form of an arrangement for conducting the invention; Figure 2 is a similar View of a preferred form of the invention and Figure 3 is an elevational view, partially in section, of a modification of part of the arrangement shown in Figure 2. All of these drawings are highly diagrammatic in form.

Turning now to Figure 1. there is shown a vertical vessel H] which may be of any convenient cross sectional shape. An outlet conduit H for solid material withdrawal is provided at the bottom of vessel Hi and a row of liquid inlet pipes 12 connect into the lower section of the vessel. Suitable spray devices [3 are connected to the pipes l2. Liquid charge may be supplied into pipes l2 and 18 respectively at their upper ends and solid material outlets l9 and 20 respectively at their lower ends. An air inlet Hi connects into the lower section of heater i5 and may communicate within the heater with gas distributors (not shown). A flue gas outlet I i3 is providednear the top of the heater. Heat transfer tubes (not shown) may be provided within the heater and a suitable heat exchange fluid such as water or steam may be supplied to these tubes via inlet 2[ and withdrawn therefrom via outlet 22. Any suitable form of kiln adapted for burning of carbonaceous deposits from solid contact material may be substituted for the heater 15. In some operations, the heating may be accomplished by means of combustion of a fluid fuel within the heater in which event a mixture of air and fuel may be supplied via inlet I l. The chamber [6 is adapted for eitheriheating or cooling the solid material depending on the particular operating conditions involved. The solid material may be 4 cooled or heated within chamber l6 by direct contact with a suitable cooling or heating gas such as flue gas or steam supplied at 23 and withdrawn at 24. Optionally, the cooling or heating may be accomplished by indirect heat transfer or by spraying a liquid onto the bed of solids in the cooling vessel.

In many operations the amount of contaminant deposit on the heat carrying material may be satisfactorily regulated by burning on the contaminant only from the material passed through heater l5. In other operations, it may be desirable to subject all of the circulating heat carrying material to burning in which event a suitable kiln may be provided in the line of pipe l3 prior to the exchanger l6. Alternatively, all of the material may be passed through vessel l5 after which a portion is diverted to vessel [6 for temperature regulation.

The exchanger l6 communicates with the upper section of vessel in via conduit 20 and branch pipes 26 which may be several in number. The heater l5 communicates with a lower section of vessel [0 through conduit (9 and branch pipes 29. The ends of pipes 29 are provided with flared members 30 to aid in the discharge of solids into the bed of heat carrying material. A separate catalytic cracking system 21 is also provided and is connected through conduit 3! and heater 32 and conduit 33 to the upper part of vessel 10.

In operation, a substantially compact column Gil of granular heat carrying material, for example petroleum coke, is maintained within vessel i8. Coke is withdrawn from the bottom of vessel ID at a suitable rate controlled by valve t! on outlet 1 Prior to its withdrawal, the coke is purged substantially free of gasiform hydrocarbons by means of an inert purge gas such as steam or flue gas supplied through conduit '10. Part of the used coke bearing a coky deposit formed during the pyrolytic conversion reaction is passed via conveyor 36 and conduit l'l into heater [5 wherein it is heated by combustion of all or part of the coky material deposited by the hydrocarbon conversion. In an exemplary operation, the coke may be heated from a convertor outlet temperature of about 800 F. to about 1100 F. at which temperature it is introduced into the lower section of column 40. The rate of heated coke supply may be controlled by means of slide valve 53 operated by rod 54 from a location outside the vessel or by other suitable means. A seal chamber 55 is provided on the conduit 19 to prevent escape of hydrocarbons. Steam may be supplied to the seal chamber via pipe 56. A petroleum residuum charge which may have been preheated to about 600 F. is introduced via conduit 46 and pipes I2 and spray devices l3 into the column 49 at a level shortly below the level of heated heat carrying material introduction.

The liquid oil is distributed uniformly onto the granular coke and heated thereby so as to effect pyrolytic cracking conversion to a lower boiling intermediate product existing in the gaseous phase except for a small amount of entrained non-vaporized liquid hydrocarbons. A coky contaminant is deposited on the heat carrying material during this reaction. The gasiform intermediate product and entrained liquid hydrocarbons pass upwardly through column 40 to be subjected to increasingly higher temperatures until the level of spreaders 30 is reached. Thereafter, the intermediate product is quenched to a substantially lower temperature by contact with the cooler coke supplied from chamber [6 via conacoop'ci duit'ZB. The solidmaterial entering from conduit :20 may be at atemperature of-about 850 F. for example. .mainderof the use'd'material withdrawn from the bottom of vessel 1-0-at800 F. and is heated to -850F. in exchanger -18. The rate and temperature or the ratealone of introductionof the heat'carrying material-onto the surface of=column 49 is.control1ed so as to cool the intermediate product to a temperature at which :thecokingor pyrolytic reaction is substantiallyinhibited, :and at which the entrained liquidhydrocarbons are deposited on the heat carrying material. If desired, the quench temperature maybe su'ificiently low to condense up to about percent .ofthe reaches in the coking zone. The liquid deposited on the heat carrying material is carried thereby down into the hotter zone below flared members so and is eventually cracked down to coke and lower boiling gasiform hydrocarbons. The term gasiform is used herein in abroad senseas covering material in' the gaseous phase under the particularconditions of pressure and temperature at which it is present regardless of what maybe the normal phase of the material under ordinary atmospheric conditions. The quenched gasiform intermediate productis withdrawn from the upper'section'of vessel fll via conduit 33 at a temperature of '850 F. for example and may lie-passed directly to the catalytic cracking system 2! or heated first to about. 900 9'50 Fxandthenpa'ssed to the catalyst reactor. The intermediate ;prodnot is converted in the catalyst reactor to a "lower boiling product containing high antiknock gasoline. Since theentrained liquidhydrocarbons, which have a high residual carbon content are left behind in the vessel 1 9,-the conversion of the petroleum residuum to high anti-knock gasoline is accomplished without -;incurring excessively high coke :deposits on thecatalyst, Also, since the entrained high carbonresidue liquid has been removed in that portion of vessel .19 wherein the granular heat carrying material is flowing, the deposition of coke on the walls of -the-vessel near the outlet and in the transfer line 33 isavoided. When the catalytic cracking system is not inoper ation the intermediate product from vessel it) may be withdrawn to storage viaconduit- 89. The used heat carrying material is conveyed by a suitable conveyor .36 or gas lift to a level above chambers l5 and I6 and then :passes in part to each stream as controlled by valves on conduits Hand 1 8. When a materialother'than'petroleum coke is employed-as the heat carrying-material; the amount of carbonaceous material thereon should be maintained at-a low constant value by burning with a combustion supporting *gas in heater [5, and if necessary, inan auxiliary 'kiln inserted before chamber It. .If the heat-transfer materialis petroleum coke, only so much of the coke deposit thereon need be burned off as will meet theheat requirements or" thecyclic system. If the amount of coke in the system builds-up it may be withdrawn as a by-product via conduit 28%. Inert gas seal zones 55 and 55' are provided on conduits 59 and to prevent escape of This material constitutes the 're-.

\6 hydrocarbons from vessel 13 into the chambers l5 and 16. It isnot essential thatchambers l5 and I6 be positioned above thevessel [0 as long as'a suitable means isprovided for solidsttrans'fer fromc'hambers Brand it to the proper levels'in vessel-l0. 7 In most operations the desired quench temperature is below'that required for the-catalytic cracking reaction and in such operations itis preferable to employ the arrangement shown in Figure '2 of the drawings- In Figures 1 and 2, equivalent elementsbear similar numerals and need not be further described. In thearran'gement shown in Figure 2 the heated heat carrying material fromheateriifi passes via conduit 88' into-a seal chamber 8! provided in the upper section of vessel'82. Part of the heated solid material passes via tubes 84 onto the surface of column 40 and the remainder passes via' tubes '85 into the lower section of the column. Slide valves 36 are provided for rate control. Cooled solid material passes from cooler it via conduit 81 and tubes!!!) into the column at an intermediate level. Flared members 89 and Sll are provided on the lower ends of tubes "85 and tubes 88 respectively. Baflles we may be provided below flared-mem here 90 to insure uniform mixing of the solid material from tubes 88 with the solids flowing down from the upper portion of the column.

In atypical operation heated solid material may be supplied through

tubes

85 and 84 at about 7 1200"v F. Cooled solid material may enter the column from tubes .88 at 700 F. Liquid hydrocarbon charge may be "supplied from conduit 9!, pipes Bland nozzles 93 into the column be'low'the level of hot heat carrying material introduction. The liquid charge is convertedin-theicoking zone A by means of the heat supplied by the heat carrying material. The intermediate conversion products carrying entrained non-vaporized liquid hydrocarbons pass up through the column to be cooled inthe quench zone B which lies between the levels of flared members '89 and 90. The quenched vapors at'about '750.F.then enter the preheating zone A whichoccupies that portion of the column above flared members :90. In the preheating zone the vapors are heated to a suitable catalytic cracking temperature, for examplev 850 F. and are then disengaged from the-column surface and passed via-conduit 33 to the catalytic reactor 55. The rate of supply of heated heat carryingmaterial to the preheating zone maybe controlled by means of plug valves 95 :to provide thedesired vapor-outlet temperature; 'Tn'erate of hot solid material supply to the coking zone may-be controlled by slide valves '86 an'd the :cool solid supply to the'quench zone may be controlled by valve 19!. Downward movement 'of'the heat carrying -material through all 'of theezones isaccomplished bywithdrawal of the usedheatcarrying material from the bottom of the vessel through conduit 1 i. This causes the heat carrying material from the zone A to join that supplied from tubes 88 into zone B and the-material from zone B joins that supplied from tubes- 85 into zoneC. A -preferred method 'of operation is to set the valves l9! and 86 so as to allow the proper proportions and amounts of cool and heated solid material to enter zones .3 and C respectively and to set the valve -"4I on outlet H tojpermit withdrawal via'conduit H of an amount of solid material which is in excess of the total ofthe solids supplied via

pipes

88 and 85 by an amount corresponding to the requirements ofzone A. :Pipes 84 then need not be throttled so that they serve to control the column surface level constant. Uniform flow and purging of the granular solid material may be accomplished by an orifice plate arrangement as shown in Figure 2. This arrangement is claimed and described in United States Patent 2,434,202 issued January 6, 1948. The catalytic reactor95 may preferably be of the moving bed type which is described in United States Patent 2,419,507, issued to Simpson et al. on April 22, 1947. Adsorbent catalyst in granular form passes downwardly through the reactor 95 and is contacted by the rising petroleum vapors which are converted to a gasoline containing product. The gasiform product is withdrawn via conduit I05. The form of the invention shown in Figure 2 offers several important advantages. It permits the preheating of the intermediate gasiform product to the cat alytic cracking temperature within the same vessel and column of solid material that is employed for the pyrolytic conversion, thereby eliminating the need for a separate furnace. Moreover, the heat required for the preheating is supplied from within the coking system by burning formed coke, thereby efiecting a saving inheating fuel requirements. In addition, the quenched stream from zone B is heated to a level substantially above its dew point in zone A thereby eliminating the danger of heavy oil condensation in the upper part of vessel 02 and in the transfer line 33. If there is any tendency for coke formation during the preheating step, it is deposited on the heat carrying material and not in the tubes of a preheating furnace. As discussed above in connection with Figure 1, in some operations the heat carrying material introduction via tubes 83 into the quench zone may be introduced at a temperatwo slightly above that of the solid material discharged from the bottom of vessel 02 via conduit II. In such operations, the chamber It may be operated as a heater. Also, in some operations the temperature of the used heat carrying material may be approximately that desired for the quench zone in which case the chamber I8 may be employed purely as a surge hopper in the cyclic system.

In order to permit greater flexibility of control in the preheating zone provision may be made for separate control of the temperature of the heat carrying material supplied onto the column surface. Such an arrangement is shown in Figure 3 which shows a modified portion of the arrange'ment in Figure 2, the rest of the arrangement remaining the same. In Figure 3, double supply chambers I01 and I are provided in the upper section of vessel '82 by means of horizontal partitions IM and I02. from heater I5 (shown in Figure 2) passes down through conduit 00 which fits through partition IOI into the chamber I06 from which it passes via tubes 85 to the pyrolytic conversion zone. A part of the heated heat carrying material is permitted to flow from conduit 80 through pipes I I0 into chamber I01 above partition IOI. Conical valves I09 mounted on slide rods III are provided to control the rate of solid material flow from pipes I10. The rods III slide through bushings H2 which should be gas tight. The temperature of the solid material in chamber I0! is controlled by admitting cooler material from an external cooler via conduit 8! to I I I. If desired, a separate exchanger (not shown) may be provided in which the solid supply for the preheating zone is regulated to the proper temperature level and then supplied into chamber Heated solid materialconduit I10 connects.

I0I' via conduits H2 and III. In this case, the pipes H0 may be eliminated. Cooled contact material passes from a cooler through pipe 81 into the lower'portion of a distributing zone I22 defined between spaced horizontal partitions [2| and I23. The contact material is delivered into the zone I22 from a confining cone I into which Cooled contact material passes from zone I22*via a plurality of pipes I into'thef' surface of the column I40 in a lower portion of the vessel. -A gas withdrawal space I4! is provided around the pipes I30 and above the column I40. It will be noted that the hot contact material supply pipes extending down from partition I02 arepositioned laterally between pipes ISO and terminate at a substantially lower level in the vessel than pipes I30, thereby providing for a, quench zone in the upper portion of the column and a conversion zone therebelow. Liquid petroleum residuum is charged from manifold I52 and nozzle pipes I53 onto the column below angle baffles I54 at a level below that of the hot contact material supply. The vapors resulting from the coking reaction pass up through the cooler material in the quench zone I where they are quenched to inhibit further reaction and to effect condensation on the contact material of entrained liquid hydrocarbons. The quenched vapors pass from the gas space MI via by-pass pipe I53 into distributor troughs I54 positioned in the bed I80 of contact material shortly above partition I23. The reactant vapors are then heated to a temperature suitable for effecting catalytic conversion thereof by means of the contact material entering from zone I01 at a suitable controlled temperature. Preheated vapors then pass via conduit I55 to the catalytic reactor. The contact material from the preheating bed I00 passes via pipes I51 onto the surface of column I40 at a temperature which is usually below that of the contact material supplied through pipes 85 but above that of the cooled material entering via pipes I30. Flow throttle cones I mounted on rods I6I which slide through bushings I62 are positioned below pipes I30. The cones may be raised or lowered by rotation of the eccentrics I85 mounted on shaft IE6 below the Y-shaped end of rods ISI. Slide valves I62 operated from the back side of the unit similarly to valves 86 of Figure 2 are mounted on pipes 05. By means of cone valves I60 and slide valves I62 the rate and relative proportion of heated and cool contact material delivery to the column I40 may be controlled. The valves are set so that the total of these two streams is less than the total contact material wihdrawn from the bottom of the vessel. The differential is automatically taken up by the contact material flowing through open pipes I5! from the preheating bed I80. It will be noted that since the other two contact material streams are individually controlled by throttle valves, the rate of contact material flow from zone I01 onto the preheating bed I may be controlled by control of the rate of solid withdrawal from the bottom of the vessel and at the same time the stream from the zone I01 serves automatically to maintain constant the surface levels of bed I80 and column I40. The escape of hydrocarbons through the solid material feed pipes is prevented by introduction of a seal gas such as steam or flue gas via pipes I95, I96 and I91 at rates suflicient to maintain the inert gas pressure in the zones of its introduction slightly greater than the reactant pressure in the. bed

I80 and column I40. u The particular operating conditionsto be employed in the process of this invention vary over a'wide range depending upon theoriginal charge stock, the heat carrying material andcatalyst employed and the desired severity of the pyrolytic "cracking reaction. In general, the operation W111 fall within the following approximate ranges of temperature:

Contact Material Streams rin Ookin Zone Broad Range. FnteD g Preferred Range.

Broad Range. Preferred Range. Broad Range. Preferred Range. Broad Range. Preferred Range.

Broad Range. Preferred Range. Broad Range. Preferred Range.

e Entegng Quench Zone o Leaving Catalytic Reactor l.

Charge to Coking Zone Broad Range.

, Preferred Range.

Broad Range.

The temperatures given above for thequench zone inlet stream are those for operations when a preheating zone is not provided) thereabove. When a preheating zone is provided the solid material inlet temperature to thequench zone 1 is somewhat lower than that given: in the above table, for example the preferred inlet temperature may be of the order 0?;650-850 F. The pressure in the coking zone is usually of the order of nearly atmospheric up to about-30 pounds per'square inch-gauge but may range up to about 200 pounds per square inch in some operations. The temperature ranges given above are for the low pressure operation; The pressure in'the catalytic reactor is usually of the orderof 5-30 pounds per square inch but may in someinstances be substantially higher. The relative rates of heat carrying material and reactant flow injthe coking, quench and preheating zones is purely a question .of thermal balance, the heat carrying material being regulated in rate of flow and inlet temperature to carry substantially the entire heating or cooling load in the zone in question. In the catalytic reactor the reactant space velocity may range from about 0.5'to'10.0 volumes of oil'charge 'per hour (measured as a liquidat 60F.) per volume of'catalystein the reaction zone." The catalyst to oil ratio may vary from about 1 to parts of catalyst per part of oil charge per-hour by weight.

The specificexamples of operation and details of apparatus arrangement and process technique given hereinabove are intended as exemplary and should not be construed as limiting the scope of this invention except asit may be limited by the following claims. 1 I claim: I

1. A method for.conversion-of-highboiling liquid hydrocarbons to lower boiling ihydrocarbon products: which: comprises: maintaining a substantiallyrcompact bed of granular solidheatcarrying material in an upright confined zone, withdrawing a stream of solid material from the lower section of said 'zone to cause downward movement of thesolid material in saidbed, introducing high-boiling liquid hydrocarbons into said bed at an intermediate level. alongits length to' contact -said-heatcarrying material and to effect a partial I conversion of said, liquid hydrocarbons to a gasiform product. containing lower boiling hydrocarbonsand a small amount of entrained unvaporizecl liquid hydrocarbons and with th deposition 7 -of a carbonaceous coky material on the heat carrying material, said liquid hydrocarbons being introduced at a temperature below that required for 1 products.

; boiling .version thereof to lower ing products.

some but only a small portion of said gasiform product, passing said ga'siform product containing entrained liquid upwardly through said bed to contact said cooler solid material whereby the 'conversion reaction is substantially inhibited and a small portion of the gasiform product is condensed and deposited upon the solid material along'with said entrained liquid, withdrawing the gas'iforrn product from the upper section of said zone and passing it into contact with a finely divided adsorbent catalyst under conditions of temperature and pressure suitable for effecting further conversion to gasiformfgasoline containing 2. A method for catalytically converting high petroleumiractions containing constituen'ts which decompose belowtheir boilin temperatures which comprises, maintaining a substantially compact column of granular heat carrying material in a confined upright zone, introducing a high boiling petroleum fractionas aliquid into said column at an intermediate level along its length to-effect thermal coking 'of said petroleum fraction to a gasiform product containing a small amount of relatively high boiling entrained liquid and to a coky deposit on the heat carrying material, introducing a first stream of heated inert heat carrying material into said column shortly above the level ofliquid hydrocarbon introduction at a temperature above that of said petroleum fraction and above the average coking temperature and sufficiently high to supply the heat required for the cokingreaction, introducing a second stream of substantially, cooler inertheat carrying material onto the surfaceor" said column, said cooler heat carryingmaterial being at a temperature; above that at which most of said product will condense, withdrawing .used

heat carrying material from the bottom of said column to cause-downward movement of the heat carryingmaterial through said confined zone,

passing the gasiform product formed in said cokingreaction along with the entrained high boiling liquidhydrocarbons upwardly within said column to contact progressively hotter heat carrying material until it reaches the level of the heated material introduction and then to contact progressively cooler heat carrying material in the upper portionof said column whereby theentrained liquid hydrocarbons are left behind on the heat carrying material as'the gasi form products leave the surface-of said column, and passing thegasiform products substantially free of entrained liq- .uid hydrocarbons'into contact with a finely divided catalyst tokeifect the-catalytic c'rackingconboiling gasoline contain- 3. A method for conversion of petroleum residuums to high antiknock gasoline comprising, maintaining a substantially compact column of granular, petroleum coke, in an elongated, confined zone, supplying, heated granular coke into said column at an intermediate level to maintain the column temperature below said level of introduction at a suitable range of coking temperatures below about 1200" F., supplying granular cokeonto the surface of said column at a temperature substantially below that of the heated coke introduction and below about 1000 F., withdrawing used granular coke from the bottom of said column, introducing petroleum residuum charge in the liquid phase into said column below the level of heated coke introduction to eifect coking of said charge to lower boiling gasiform hydrocarbons, said petroleum charge being introduced at a temperature insufiicient to effect its coking so that the heat required for the coking is supplied by said granular coke passing the gasiform hydrocarbons upwardly through said column along with a small amount of nonvaporized liquid hydrocarbons to contact first the heated coke and later the cooler coke in the upper section of said column, whereby the gasi-form product is cooled to a temperature substantially below the highest level to which it was heated by said heated coke, whereby the entrained liquid hydrocarbons areideposited on said coke, withdrawing the gasiform product from said. column below the temperature required for its catalytic cracking conversion temperature and heating it to said catalytic cracking conversion temperature which is above about 800 F., passing the heated gasiform product into contact with a granular cracking catalyst to effect its further conversion to a high antiknock gasoline containing product and separating said gasoline containing product from said catalyst. I

4. A method for conversion of petroleum residuums to high antiknock gasoline comprising, maintaining a substantially compact column of granular, substantially inert heat carrying material in an elongated, confined zone, introducing petroleum residuum charge as a liquidrinto the lower portion of said column to effect coking thereof at a suitable range of coking temperatures to provide a stream of lower boiling hydrocarbons in the gaseous phase in which is entrained some non-vaporized liquid hydrocarbons, passing said stream upwardly into a cooler and intermediate portion of said column wherein it is cooled by contact with the heat carrying material to a quench temperature at which the coking reaction is substantially inhibited and the entrained liquid is deposited on the solid heat carrying material, said quench temperature being substantially below the highest temperature reached in said lower portion of said column and being below the suitable catalytic cracking temperature, passing the cooled stream, substantially free of entrained liquid up through an upper portion of said column wherein itstemperature is raised to a suitable temperature for its catalytic conversion which is below the maximum temperature reached by said stream in said lower portion of the column, withdrawing the heated stream from said column and passing it into contact with a finely divided catalyst to efiect its cracking conversion to a gasoline containing product in a separate zone and effecting a separation of said product for the used cracking catalyst, introducing a first portion of inert solid heat carrying material into said column at a level shortly above 12 that of the liquid residuum charge and at a temperature substantially above the average coking temperature in said lower portion of said column,

introducing a second portion of said heat carrying material into said column at an intermediate level below its surface and above the level of said first portion and at a quench temperature substantially below that of said first portion, controlling the rate and temperature of introduction of said second portion of heat carrying material to effect the quenchin of said stream of gasiform hydrocarbons as aforesaid, introducing a third portion of said heat carrying material onto the surface of said column at a temperature substantially abovethat of said second portion, controlling the rate of introduction of said third portion to effect heating of said .gasiform stream to said suitable catalytic cracking conversion temperature and withdrawing said inert heat carrying material at a controlled rate from the bottom of said column.

5. A method for conversion of petroleum residuums to high antiknock gasoline comprising, maintaining a substantially compact column of granular substantially inert heat carrying material in an elongated, confined zone, introducing petroleum residuum charge as a liquid into the lower portion of said column to effect coking thereof at a suitable range of coking temperatures to provide a stream of lower boiling hydrocarbons in the gaseous phase in which is entrained some non-vaporized liquid hydrocarbons, passing said stream upwardly into a cooler and intermediate portion of said column wherein it is cooled by contact with the heat carrying material to a quench temperature at which the coking reaction is substantially inhibited and the entrained liquid is deposited on the solid heat carrying material, said quench temperature bein substantially below the highest temperature reached in .said lower portion of said column and being below the suitable catalytic cracking temperature, passing the cooled stream, substantially free of entrained liquid up through an upper portion of said column wherein its temperature is raised to a suitable temperature for its catalytic conversion which is below the maximum temperature reached by said stream in said lower portion of the column, introducing a first portion of inert solid heat carrying material into said column at a level shortly above that of the liquid residuum charge and at a temperature substantially above the average coking temperature in said lower portion of said column, introducing a second portion of said heat carrying material into said column at an intermediate level below its surface and above the level of said first portion and at a quench temperature substantially below that of said first portion controlling the rate and temperature of introduction of said second portion of heat carrying material to effect the quenching of said stream of gasiform hydrocarbons as aforesaid, introducing a third portion of said heat carrying material onto the surface of said column at a temperature substantially above that of said second portion, controlling the rate'of introduction of said third portion to effect heating of said gasiform stream to said suitable catalytic cracking conversion column, withdrawing used heat carrying material at a controlled rate from the bottom of said column, passing a part of the used heat carrying material through a separate heat- 1 ing zone wherein it is heated to a temperature suitable for reuse, uti1izin ga part of the heated heat carrying material to supply said first portion of heat carrying material introduced into said column, utilizing. the remainder of the heated heat carrying material to supply said third por tion introduced onto said column, passing the remainder of the ,used heat carrying material through a separate heat exchange zone wherein it is regulated to a suitable quench temperature and utilizing the latter heat carrying material to supply said second portion introduced into said column, withdrawing the heated stream from said column and passing it into contact with a finely divided catalyst to effect its cracking conversion to a gasoline containing product in a separate zone and efiecting a separation of said product from the used cracking catalyst.

6. A method for conversion of petroleum residuums to high antiknock gasoline-comprising, maintaininga substantially compact column of granular, substantially inert heat carrying material in an elongated, confined zone, introducing petroleum residuum charge as a liquid into the lower portion of said column to effect partial conversion and gasification thereof at an elevated temperature suitable for pyrolytic cracking of the residuum to form a stream of lower boiling gasiform hydrocarbons containing a small amount of entrained non-gasified liquid hydrocarbons, passing said stream upwardly into a cooler and intermediate portion of said column wherein it is cooled by contact with the heat carrying material to a quench temperature at which the pyrolytic cracking reaction is substantially inhibited and a minor fraction of the stream is condensed and deposited on the solid heat carrying material along with the liquid entrained from the lower portion of said column, said quench temperature beingsubstantially below the highest temperature reached in said lower portion of said column and being below the suitable catalytic cracking temperature, passing the cooled stream, substantially free of entrained liquid up through an upper portion of said column wherein its temperature is raised to a suitable temperature for its catalytic conversion which is below the maximum temperaturereached by said stream in said lower portion of the column, withdrawing the heated stream from said column and passing it into contact with a finely divided catalyst to effect its cracking conversion to a gasoline containing product in a separate zone and effecting a separation of said product from the used cracking catalyst, introducing a first portion of inert solid heat carrying material into said column at a level shortly above that of the liquid residuum charge and at a temperature substantially above the average pyrolytic cracking temperature in said lower portion of said column, introducing a second portion of said heat carrying material onto the surface of said column at a temperature at least equal to said suitable catalytic crackin temperature and substantially below that of said first portion of heat carrying material, introducing a third portion of said heat carrying material into said column at a level intermediate the levels of introduction of said first and second portions of heat carrying material and at a quench temperature which is below that of said second portion but insufiiciently,

low to condense most of said stream of lower boiling hydrocarbons formed in saidlower portion of said column, and

heat carrying material at acontrolled rate from the bottom of said column.

'7. A method for conversion of highiboiling liquid petroleum fractions to a lower boiling gasowithdrawing said inert 14 line containingconversion product' comprising, maintaining a substantially compact column of granular heat carrying material of low catalytic activity extending upwardly through a lowermost pyrolytic conversion zone, anintermediate quenching zone and an upper preheating zone,

withdrawing :heat carrying material from, the bottom of :said column to cause downward move existing mainly in the gaseous phase butcontaining small'amounts of non-vaporizedliquid hydrocarbonasubjectin a second portion of the heat carrying material withdrawn frem-sai'd-celunmto cooling to effect reduction in its temperature to a level suitable-for substantially quenching the pyrolytic cracking reaction but above that which would cause condensation of more than about 15 percent of said intermediate product and introducing this latter-material into said column at an intermediate level corresponding to the upper section of said quench zone," passing the gasiform intermediate product with entrained liquid up wardlyfrom said pyrolytic conversion zone into contact with the cooler heat carryingmaterial in said quench zone whereby the reaction is substantially inhibited'and the entrained liquid is deposited onto the heat carrying material, adjusting the temperature of a third portion of the heat carrying material withdrawn from said columnto a level intermediate that of said first and second portions and at least equal to a suitable temperature for the catalytic cracking conversion of said intermediate product and supplying said third portion onto the surface of said column which corresponds to the top of said upper. heating zone, passing the quenched intermediate gasiform productupwardly from said quench zone into contact with-the hotter heat carrying material in said heating zone whereby it is heated to a suitable temperature for its catalytic cracking conversion and passing the heated intermediate product into contact with a suitable finely divided adsorbent cracking catalyst in a separate, confined zone to efiect its conversion to a gasoline containing product.

8. -A method for coking high boiling petroleum fractions to lower boilin products comprising, maintaining a substantially compact column of granular heat carrying material of low catalytic activity extendingthrough a lower coking zone and an upper quench zone, withdrawing heat carrying material from the bottom of said column terial therein, whereby it undergoes coking to form a lower boiling gaseous product existing mainly in the gaseous phase but containing small amounts of high-carbon-residue liquid hydrocarbons, subjecting a second portion of the heat carrying material withdrawn from said column to cooling to effect reduction in its temperature to a level suitable for substantially quenching the coking reaction but above that which would cause condensation of more than about 15 percent of said lower boiling product and introducing this latter material into said column at a level corresponding to the upper section of said quench zone, passin the lower boiling product with entrained liquid upwardly from said coking zone into contact with the cooler heat carrying material in said quench zone whereby the reaction is substantially inhibited and the entrained highcarbon-residue liquid is deposited upon the heat carrying material, withdrawing said lower boiling product in gaseous form and substantially free of entrained liquid hydrocarbons from the upper section of said column at a temperature above that at which more than 15 percent of the product condenses,

9. A method for conversion of petroleum residuums to high antiknock gasoline comprising, maintaining a substantially compact column of granular, substantially inert heat carrying material in an elongated, confined zone, introducing petroleum residuum charge as a liquid into the lower portion of said column to eifect partial conversion and gasifioation thereof at an elevated temperature suitable for pyrolytic cracking of the residuum to form a stream of lower boiling gasiform hydrocarbons containing a small amount of entrained non-gasified liquid hydrocarbons, passing said stream upwardly into a cooler and intermediate portion of said column wherein it is cooled by contact with the heat carrying material to a quench temperature at which the pyrolytic cracking reaction is substantially inhibited, said quench temperature being below a suitable catalytic cracking temperature, passing the cooled stream up through an upper portion of said column wherein its temperature is raised to a level suitable for catalytic conversion of the hydrocarbons, withdrawing the heate stream from said column and passing it into contact with a suitable catalyst to effect its cracking conversion to a product containing high octane gasoline and effecting separation of said product from the cracking catalyst, introducing a first portion of inert solid heat carrying material into aid column at a level shortly above that of the liquid residuum charge and at a temperature substantially above the average pyrolytic cracking temperature in said lower portion of said column, introducing a second portion of said heat carrying material onto the surface of said column at a temperature at least equal to said suitable catalytic cracking temperature and substantially below that of said first portion of heat carrying material, introducing a third portion of said heat carrying material into said column at a level intermediate the levels of introduction of said first and second portions of heat carrying material and at a quench temperature which is below that of said second portion but insufliciently low to condense most of said stream of lower boiling hydrocarbons formed in said lower portion of said column, controlling the rate of introduction of the first and third portions of the heat carrying material into said column to supply the heat for said py olytic reaction and to supply the cooling capacity for the product quenching respectively, withdrawing heat carrying material from the bottom of said column at a rate which is in excess of the total rate of supply of said first and third portions by an amount approximately equal to the required rate of supply of said second portion to effect the reactant preheating and supplying said second portion onto the surface of said column at a rate adjusted to maintain constant the surface level of said column.

10. A method for efiecting high temperature conversions of high boiling petroleum fractions comprising maintaining a substantially compact column of granular heat carrying material in a confined upright zone, introducing a high boiling petroleum fraction as a liquid into said column at an intermediate level along its'length to effect thermal cokin of said petroleum fraction to a gasiform product containing a small amount of relatively high boilin entrained liquid and to a coky deposit on the heat carrying material, introducing a first stream of heated inert heat carrying material into said column shortly above the level of liquid hydrocarbon introduction at a temperature above the average coking temperature and at a rate positively controlled to effect upply as sensible heat in the heat carrying material the heat required for the coking reaction, introducing substantially cooler heat carrying material into said column at a higher level therein spaced substantially below the column surface, said cooler heat carrying material being at a temperature substantially below said coking temperature and the rate of said cooler heat car ying material introduction being positively controlled to efiect quenching of the gasiform product flowing up from the lower and hotter portion of said column and the deposition of entrained liquid on the solid material, withdrawin heat carrying material from the bottom of said'column at a rate substantially above the combined rates of introduction of said first and second streams, flowing by gravity a stream of heat carrying material existing at a temperature intermediate said first and second streams from an external supply zone down onto the surface of said column to maintain said column continuously replenished and to supply into the upper portion of said column sufficient heat to raise the temperature of the quenched gasiform product to a level intermediate the coking and quench temperatures and withdrawing the reheated gasiform product from the upper portion of said column.

11. A method for coking high boiling petroleum fractions to lower boiling products comprising, maintaining a substantially compact column of granular heat carrying material of low catalytic activity extending through a lower coking zone and an upper quench zone, withdrawing heat carryin material from the lower section of said column to cause downward movement of the heat carrying material through all of said zones, supplying heat carrying material at a temperature suitable for supporting the coking reaction and upplying it into said column at a level corresponding to the upper portion of the coking zone, introducing a high boiling liquid petroleum fraction into said coking zone at a temperature below that of said heat carrying material and insufficient to provide the heat for said coking reaction to contact said heat carrying material therein, whereby it undergoes coking to form a lower boiling gaseous product existing mainly in the gaseous phase but containing small amounts of 17 high-carbon residue liquid hydrocarbons, introducing a second portion of solid heat carrying material into aid column at a level corresponding to the upper section of said quench zone at a temperature level suitable for substantially quenching the coking reaction and also condensing a minor fraction of but not more than about 15 percent of said lower boiling product, passing the lower boiling product with entrained liquid upwardly from said coking zone into contact with the cooler heat carrying material in said quench zone, whereby the reaction is substantially inhibited and a minor fraction of the lower boiling product stream is condensed and deposited on the solid heat carrying material along with said entrained high-carbon-residue liquid, withdrawin the remaining lower 18 boiling product in gaseous form and substantially free of entrained liquid hydrocarbons from the upper section of said column at a temperature above that at which more than 15 percent of the product condenses.

SYLVANDER C. EASTWOOD.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 7 2,348,699 Tuttle May 9, 1944 2,403,608 Payne et al July 9, 1946 2,466,005 Crowley Apr. 5, 1949 2,513,294 Eastwood et al July 4, 1950

Claims

1. A METHOD FOR CONVERSION OF HIGH BOILING LIQUID HYDROCARBONS TO LOWER BOILING HYDROCARBON PRODUCTS WHICH COMPRISES: MAINTAINING A SUBSTANTIALLY COMPACT BED OF GRANULAR SOLID HEAT CARRYING MATERIAL IN AN UPRIGHT CONFINED ZONE, WITHDRAWING A STREAM OF SOLID MATERIAL FROM THE LOWER SECTION OF SAID ZONE TO CAUSE DOWNWARD MOVEMENT OF THE SOLID MATERIAL IN SAID BED, INTRODUCING HIGH BOILING LIQUID HYDROCARBONS INTO SAID BED AT AN INTERMEDIATE LEVEL ALONG ITS LENGTH TO CONTACT SAID HEAT CARRYING MATERIAL AND TO EFFECT A PARTIAL CONVERSION OF SAID LIQUID HYDROCARBONS TO A GASIFORM PRODUCT CONTAINING LOWER BOILING HYDROCARBONS AND A SMALL AMOUNT OF ENTRAINED UNVAPORIZED LIQUID HYDROCARBONS AND WITH THE DEPOSITION OF A CARBONACEOUS COKY MATERIAL ON THE HEAT CARRYING MATERIAL, SAID LIQUID HYDROCARBONS BEING INTRODUCED AT A TEMPERATURE BELOW THAT REQUIRED FOR ITS PARTIAL CONVERSION, INTRODUCING HEATED SOLID HEAT CARRYING MATERIAL INTO AN INTERMEDIATE PORTION OF SAID BED NEAR THE LEVEL OF LIQUID HYDROCARBON INTRODUCTION AT A TEMPERATURE ABOVE THAT OF THE LIQUID HYDROCARBONS AND SUFFICIENTLY HIGH TO SUPPLY THE HEAT REQUIRED FOR EFFECTING THE VAPORIZATION AND SAID PARTIAL CONVERSION OF SAID LIQUID HYDROCARBONS, SUPPLYING COOLER SOLID HEAT CARRYING MATERIAL TO THE SURFACE OF SAID BED AT A TEMPERATURE CONTROLLED AT A LEVEL SUITABLE FOR QUENCHING THE CONVERSION REACTION AND FOR CONDENSING SOME BUT ONLY A SMALL PORTION OF SAID GASIFORMPRODUCT, PASSING SAID GASIFORM PRODUCT CONTAINING ENTRAINED LIQUID UPWARDLY THROUGH SAID BED TO CONTACT SAID COOLER SOLID MATERIAL WHEREBY THE CONVERSION REACTION IS SUBSTANTIALLY INHIBITED AND A SMALL PORTION OF THE GASIFORM PRODUCT IS CONDENSED AND DEPOSITED UPON THE SOLID MATERIAL ALONG WITH SAID ENTRAINED LIQUID, WITHDRAWING THE GASIFORM PRODUCT FROM THE UPPER SECTION OF SAID ZONE AND PASSING IT INTO CONTACT WITH A FINELY DIVIDED ADSORBENT CATALYST UNDER CONDITIONS OF TEMPERATURE AND PRESSURE SUITABLE FOR EFFECTING FURTHER CONVERSION TO GASIFORM, GASOLINE CONTAINING PRODUCTS.