US2348156A - Conversion of hydrocarbon oils - Google Patents

Description

y 2, 1944. B. SHEPPARD 2,348,156

CONVERSION OF HYDROCARBON OILS Filed June 15, 1939 2 She ets-Sheet l 42 a, 9 Gauge Rad WWW A INVENTOR ATTORNEY 1 BRUCE SHEPPARD.

v Patented May 2, i944 um- 15D S A-res, PATENT or-P cs I .cc wosoigiwm oms Bruce Sheppard, Bridgewater Township,

Somerset County, N. 1., asllgnor to Petroljeum Oonversion 'N. .L, a oorporationof Delaware Application June is, 1939, Serial No. 21am 3 Claims. (01. 196-52) My present invention relates to improvements in the art of hydrocarbon oil conversio Processes of hydrocarbon oil conversion have for some years been proposed in which the hydrocarbon material is passed through a'reacticn zone containing a solid contact agent, which by the action of adsorption or catalysts or decarbonization or otherwise, favorably affects the conversion process, either by increasing the yield or by improving the quality of the products, especially in the increased in antiknock value of vent leakage of, the'conversion products either the gasoline product. considerably difficulty, howevenhas been. experienced by reason of the fact that the solid contact agents become quickly coated with heavy tars or with free carbon, which prevent access, of the hydrocarbon to the agent, especially by choking up the'flne passages through the agent. To overcome this difllculty the proposal has been made to restore in situ the free. surface of the contact substance by periodically burning out the-tar or carbon. In

so doing, however, the temperature of combustion is often high enough to affect the contact substance adversely, or to cause damage to the containing vessel, and in some cases the carbon can not be completely removed because of failure of the air to penetrate into the contact mass. Other attempts have involved the provision of molded contact masses in special-containers with complicated devices for automatically cutting out a given contact mass, regenerating the same, and cutting in the regenerated contact mass, such arrangements involving great expense and unsatisfactory operation.

It is therefore aprincipal object of my present invention to overcome these difliculties by providing for substantially continuous movement of the contact substance during the conversion period, with the substantially continuous removal of the spent contact mass from the conversion zone, thereby obviating the necessityof regenerating the contact mass inthe same apparatus which is used for conversion. In this manner fresh surfaces of contact substance are constantly presented in the conversion process, stop- Dase of the operation by deposition of carbon and tar is obviated, the capacity of the equipment for conversion is increased as the regeneration of the contact. mass is conducted separately and in apparatus especially adapted for this purpose.

.A further object of my invention is to facilitate the conversion reaction by providing for the introduction into the conversion zone of a hot inert gas, preferably a hydrocarbon gas,'for both heating the said zone and for facilitating the release of the cracked products- A further object also is to provide for the preheating of the solid contact material prior to its introduction into the column or reaction zone, preferably by use of said hot gas. A still further object is to provide forcirculation of the inert gas in a manner "to preinto thebulk supply of the contactmaterial or into the accumulation of spent material from the conversion zone.

Other advantages and objects to be attained will be apparent as the description proceeds.

Referring to the drawings,

Fig. 1 is a view in side elevation, partly in vertical section, of an illustrative embodiment;

Fig. 2 is an enlarged view of a form of valve employed for moving the contact substance;

Fig. 3 is aside view of the device shown in Fig. 2.

Fig. 4 is a view in vertical section of a modifled reaction chamber and valve for material;

Fig. 5 is an elevational view showing the lower end "of the reaction chamber. the valve employedv and the upper portion of the hopper for receivins spent contact material; Fig.6isaviewonlineHofFlg.4.

In carrying out myinvention I make use of I a hopper for fresh contact material leading into a conversion chamber or column, desirably well insulated, a valve for controlling the flow of contact material through the reaction chamber, and a hopper for the spent contact material. In addition, means are provided for maintaining the proper temperature within the reaction chamber. For a complete understanding of the inveri- 'tion. reference is now made to the following detailed description of the illustrative embodiments. I

Referring to Fig. 1, III is a hopper to be filled with the desired contact material,-wi'th the nature of which this invention is not concerned except'that it be of a particle size as .will flow freely and. provide for the free passage of vapors therethrough, all as will be evident to those skilled in the art. Specific contact materials which have been successfully employed are .silica gel, silica gel on which carbon has been deposited,

silica gel on which aluminum oxide has been deposited, activated carbon of various kinds.

- Hopper "terminates in a neck or pipe H ex tending into the top of the reaction chamber [2 so as to provide a vapor space it above the level ll of the contact material in said chamber. As shown in Fig; 1, the reaction chamber l2 comthe contact prises an inner wall spaced from which is a jacket l6. Surrounding the latter is insulating material ll. Heatingfluid is supplied within said jacket by inlet pipe l8 and exit pipe l9. Reaction chamber l2 terminates in a reduced portion communicating with pipe 2| containingvalve chamber 22,, pipe 2| thereafter communicating with ahopper 23 for the spent contact material. Various other inlet and exit pipes are also shown, which will be referred to specifically during the description of the process.

As shown in Figs. 1 and 2,valve chamber 22 contains avalve 25 of the start type, the same being mounted upon a shaft 28 (Figs. 2 and 3) driven bymotor 21 throughreduction gears 28.

. off except forinlet line 32 at the bottom of thelower hopper 23 and inletpipe 34 on upper hopper l0, whereupon flue gas, steam or other inert gas under suitable pressure is forced in by lines 32' and SI to sweep air out of the system, the purge gas leaving bylines 35 and 26 and discharging into the atmosphere at the top of the reaction chamber. When the air has been dis-' placed from the system thepipes 32, 34 and 36 are closed off by valves therein, as shown, and hot inert 'gas, preferably hot hydrocarbon gas, termed flash gas, is admitted through valved pipes- 31 and 38. The hot flash gas may have a temperature of 850 F. 'more or less, andvalve 39 inpipe 35 kept closed until the pressure in the system is built up to any desired value; for example, 10 pounds per square'inch or 100 pounds per square inch, after whichvalve 39 is opened and flow continued through the contact material imtil the latter is brought up to substantially the conversion temperature. After the run is under waythe flashv gas admitted in illmay be somewhat cooler than that stated inorder that it may pick up heat from the spent contact material in and above pipe 2|. Then while flash g'as continues to be admitted throughpipes 31 and 38, valve 4! inline 6| leading to the reaction chamber I2 is opened and oil vapor or a mixture of. oil vapor and liquid oil from a suitable vaporizing system, not shown, admitted through said line (ll). The mixture of vapors and gases leaves the conversion system by line SI. Pres-.

sure in the reaction chamber I2 is maintained slightly less than that Of the gas admitted bypipes 81 and II. as for example, 9 pounds .per

square'inch or 98 pounds per square inch, respectively, with 10 pounds per square inch or 100 poimds per square inch for the pressure of the flash gas. The slightly greater pressure of the hot gas. as compared to the vapors insures that there will be no leakage of the vapors from the the desired rate, the star valve. 25 is rotated at a uniform rate as by themotor 21 andgears 28..

The motion or thestar valve 25 transfers the contact substance from conversion chamber l2 through thereceiver 23, at which time the column of contact material in chamber 12 gradual-' ly drops and fresh material from hopper i0 passes. by way of pipe ll into the conversion chamber. The operation is continued untilthe hopper it has been emptied, as may be determined by testing with a gauge rod 52, passing through a gland 42a. Preferablyreceiver 28 has sufllcient capacity to hold the entire charge from the hopper IO and conversion chamber I2. The

condition of the charge in the system may be I further ascertained by viewing through the peep hole ll inhopper 23.

During the operation of the system, heating fluid, as for example hot flue gas, is passed through the space between the inner wall of the conversion chamber In and the jacket It by ad-; mitting same through pipe is and removing it through pipe is; or, if desired, flash gas may be" used for this purpose, heat being conserved in the chamber by the insulating material H. Desirably one or more additional inlets for hot gas may be provided-throughout the column, one such inlet being indicated at It. Occasionally some of the contact mass tends to stick in thestar valve 25 due to adherent tars or soft coke. To remedy this, the supply of heated gas through pipe 31 may be increased by further opening the valve (31a) controlling same. Or, to prevent tars from reachingvalve 25, hot gas may be admitted throughpipe 44 immediately above valve When the run is completed, as determined by the fact that hopper iii no longer contains any contact material, and by the fact that thereceiver 28 is filled to the level ofpeephole 30, the admission-or vapor through pipe ll is stopped by closing valve 10, the admission ofgas bylines 38 and" is continued to sweep all vapors out of the system, whereupon allvalves excepting valve 39 are closed; and when the pressure has dropped.valve 38 is also closed. The system may then be purged and cooled by means of or cold fluegas using line 32 for admission and line I for discharge. when the cooling has been carried far enough to prevent spontaneous ignition of the carbon-loaded contact substance. bottom flange ll is removed and the spent contact substance is permitted to drop into a car (not shown), and is transported into a. regenerator which latter may consist of a rotary kiln or other device in which the contact substance is conversion chamber into either the hoppers II or 2 3, the vapors and gases leaving the reaction chamber through pipe :5. The vapors and gases from the line 2| pass to a recovery system (not shown), which separates the liquid products, fractionating them simultaneously as desired, yielding a lean gas substantially free of C and heavier hydrocarbons, which lean gas may be heated and propelled to provide the flash gas for the system.

when the admission of vapors has reached 10 regenerated by burning with air.Top flange 50 is similarly removed, the hopper is filled with fresh contact material and the run repeated.

The temperatures employed in the reaction chamber are those which have beenfoimd to be best for this type of conversion, namely: 850 F.-950 F. for materials such as gas oil, 950' F.- 1025 F. for such materials as straight run gasoline for reforming. If the conversion temperature is established at 850 F., for example, the temperature of the inert'or flash gas may be 860-875 F., it being desirable to vary either the temperature or volume of the flash gas in order that the temperature of the exiting reaction products may be kept at a constant value during the run.

Fig. 4 shows a similar reaction-chamber to that of Fig. 1 exce n'sthat heat is supplied to the employed, the same being the subject of a co-- pending application filed August 2, 1939. Serial No. 287,891, in the name of William E. Joor, Jr. In this form of valve a flat approximatelysemicircular plate 56, preferably about half the thickness of the distance betweenspacing plates 51 and 58 suitably secured together by means of devices 51a, is employed, the same being mounted for rotation in bearing 59 ofplate 58, means for rotating same consisting of amotor 60 andgears 6|. When spacingplate 58 is uncovered beneath the discharge end of the conversion chamber [2, the charge drops down thereupon, whereupon the deposited material is swept by leadingedge 62 of said plate across the opening of pipe 2|. By use of this type of valve a, minimum of crushing of the contact substance takes place. may be employed. It is also possible to operate Any other type of measuring valve 2. In the method of hydrocarbon oil conversion in which the conversion to other hydrocarbon compounds of difie'rent properties is brought about by pyrolysis in the presence of a solid contact material or agent, the improvement which consists of moving in a column said contact material from a source of supply through' a conversion chamber andto a receiver therefor, introducing hydrocarbon vapor to be converted adjacent one end of said chamber, withdrawing converted products adjacent the other end of said chamber, supplying hot inert gas at points spaced away from the inlet and outlet for the hydrocarbon vapor to be converted for the flow of said gas concurrently with the contact material entering said conversion chamber and countercurrently to the contact material leaving said conversion chamber, said hot inert gas being suppliedat a somewhat greater "pressure the unit continuously by providing for the periodic admission to the hopper IU of additional fresh contact substance and removal periodically from thereceiver 23 of spent contact substance. Other variations in the process and apparatus will occur to those skilled in the art,

the spirit of my inventhis purpose.

I claim: 1. In the method of hydrocarbon oil conver-' sion in which the conversion to other hydrocarbon compounds of difl'erent properties is brought about by pyrolysis in the presence of a solid contact material or agent,the improvement.

which consists of moving in a, column said contact material from a source of supply through a conversionchamber and to a receiver therefor, introducing hydrocarbon vapor to be converted adjacent one end of said chamber, withdrawing converted products adjacent the other end of said chamber, supplying hot inert gas at points above and below the path of said vapors to be converted, said gas being supplied at a somewhat greater pressure than that existing in said chamber to prevent leakage of vapors ,of conversion from said chamber into said source of supply or into said receiver, said inert gas being at a sumcient temthan that existing in said chamber to prevent leakage of vapors of conversion from said chamber into either said source of supply or said receiver, said gas being of quantity and temperature adequate to supply heat for the maintenance of the active conversion temperature of said hydrocarbon vapor, and withdrawing said gas admixed with said converted vapor products.

3. In the method of hydrocarbon oil conversion in which the conversion to other hydrocarbon compounds of difierent properties. is brought about by pyrolysis in the presence of a solid contact material or agent, the improvement which consists of moving in a column said contact material from a source of supply through a conversion chamber and to a receiver therefor, introducing hydrocarbon vapor to be converted adjacent one end of said chamber, withdrawing converted products adjacent the other end of said chamber, supplying hot inert gas at points spaced away from the inlet and outlet for the hydrocarbon vapor to be converted for the flow of said gas concurrently with the contact material entering said conversion' chamber and countercurrently to the contact material leaving said conversion chamber, said hot inert gas being supplied at a somewhat greater pressure than,-

that existing in said chamber to prevent leakage of vapors of conversion from said chamber into either said source of supply or said receiver, said gas being of quantity and temperature adequate to supply heat for the maintenance of the active conversion temperature of said hydrocarbon vaponand withdrawing said gas admixed with said converted vapor products, withdrawing a measured quantity of said contact material from said chamber, and prior to said withdrawal of said material introducing an additional stream of hot inert gas into said contact material to dry it Just before its withdrawal from said chamber.

BRUCE SHEPPARD.

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