US2587670A - Processing liquid hydrocarbons - Google Patents

Description

March 4, 1952 w. w. wElNRlc-H 25582670 PROCESSING LIQUID HYDROCARBNS Filed Feb. l, 1950 Snnentor Patented Mar. 4, 1952 TENT OFFICE PROCESSING LIQUID HYDROCARBONS William W. Weinrich, Wallingford, Pa., assigner to Houdry Process Corporation, Wilmington, `Del., a corporation of Delaware Application February 1, 1950, Serial No. 141,723

12 Claims.

The present invention relates to systems and methods for conversion or other processing of hydrocarbons in contact with a granular contact mass and is particularly directed to improvements in the operation of such systems ,wherein the granular mass is circulated to and from a reaction Zone or treating Zone. The invention is especially concerned with those systems and operations wherein the granular contact mass during such circulation is elevated from a lower to an upper level in the system by a lifting fluid stream.

Various hydrocarbon conversion or treating operations employ systems of the type above designated; for example in catalytic conversion of hydrocarbons using a moving bed of adsorptive granular catalyst as in cracking, desulfurization, reforming, etc. Other operations coming into consideration include those wherein a granular contact mass, having little or no catalytic activity, is employed chiefly as a means of transferring contained sensible heat to an oil to be processed, whether for the purpose of thermally cracking or precoking the oil, or for heating the same to required reaction temperature or to vaporization temperature in the case of previously unvaporized liquid oils. While certain aspects of the present invention are applicable to operations of the various types hereinbefore designated, the invention will be more particularly described in connection with the cracking of normally liquid hydrocarbons in contact with adsorptive catalysts to products of lower boiling point and lower molecular weight, such as products in the gasoline boiling range.

Normally liquid hydrocarbons when subjected to certain elevated temperatures, whether or not in the presence of a catalytically active mass, break down to form solid carbonaceous or hydrocarbonaceous deposits called coke As a general rule higher boiling hydrocarbons at a given cracking severity display a comparatively greater tendency to form coke deposit. Where such coke material is inherently or concomitantly formed as a result of contact of hydrocarbons at elevated cumulation of coke on non-circulating contact mass which cannot be subjected to regeneration, or on parts of the apparatus as a result of cokeproducing hydrocarbons remaining on the hot walls thereof, in many instances constitutes a severe problem, often to the extent of precluding practical adaptation of a processing technique that would otherwise be highly desirable from the standpoint of eciency and economy of operation.

It is often found desirable in connection with moving bed hydrocarbon conversion andv treating operations to contact hydrocarbons in liquid state With the hot catalyst or other hot contact mass for purposes of vaporizing and/or otherwise converting such hydrocarbons to vaporized products. The handling of hydrocarbons in liquid state, for instance, offers important advantages particularly but not exclusively in connection with further cracking of condensed gas oil from a catalytic cracking operation; also in cracking or pre-coking of high boiling liquid fractions not readily vaporized below coking temperatures, such as fractions obtained as bottoms in ash vaporization of a crude oil or other oil charge; and in other operations generally where it sought to take advantage of the sensible heat content of hot catalyst or other contact mass from regeneration by directly transferring heat therefrom to relatively cooler hydrocarbons. In practical operation considerable diiculty has been experienced in distributing the liquid; oil uniformly in or on the contact mass, and nonuniform distribution of the oil results in deficient conversion or processing of the oil by reasons of localized cooling of the granular contact mass and in irregular distribution of coke in the contact mass, resulting in regeneration diculties, such as the development of localized hot spots during regeneration of the contact mass. In addition, liquid hydrocarbons migrating from the zone of intended contact with the granular contact mass, may deposit on metallic or other hot surfaces of the apparatus adjacent to the zone with consequent coking, leading to the undesirable accumulation of interfering quantities of coke on such surfaces.

In accordance with the present invention, the above noted drawbacks are overcome by a novel arrangement and operation wherein the liquid hydrocarbons are contacted with and distributed on hot granular catalyst or other hot adsorptive granular contact mass prior to the admission of the granular mass to a processing vessel through Which Such mass descends as a compact bed dur- 3 ing processing of hydrocarbons in contact therewith. Uniform distribution of the liquid hydrocarbons in the contact mass is obtained by introducing the liquid into contact with an upwardly moving stream of the contact mass in a vapor lift conduit. A large portion of the liquid hydrocarbons thus introduced, and While in contact with the hot freshly regenerated contact mass, is vaporized or otherwise converted to vapor products during travel of the contact mass in the lift. The vaporized effluent from the lift can then be contacted in vapor form With a gravitating bed of the contact mass under desired conditions in a reactor or other processing vessel. Any unvaporized liquid in the lift conduit will be distributed in and adsorbed by the granular mass, so that no unadsorbed free liquid as such is admitted to the said reactor or processing vessel and none is deposited on the lift Walls.

In my copending application Serial No.

136,444, filed January 3, 1950, of which the pres-Y ent application is a continuation in part, a novel arrangement and operating method is described wherein liquid hydrocarbons are introduced within the lower portion of the lift channel wherein the contact material is present in comparatively high concentration; complete and uniform distribution of liquid on the contact material is thus favored. It has now been found that under certain conditions it is unnecessary to limit the introduction of liquid to the lower portion of the lift or to a region of the lift con duit wherein the .contact material is present in relatively high concentration. Complete and substantially uniform distribution of liquid hydrocarbons on the contact material within the lift conduit vcan be obtained, particularly in .operations involving the use of an adsorptive contact mass, by introducting the liquid peripherally into the lift conduit into engagement with the upwardly moving contact material, the liquid hydrocarbons being advantageously introduced through diarnetrically opposed paired inlet opening into the lift conduit.

In that form of lift employing an annular stream of gasiform lift medium flowing into the bed of contact material immediately below the mouth of the lift conduit, the flow pattern of the contact material is such that at the bottom of the lift conduit and for a short height thereabove within the conduit, the contact material. is more concentrated near the radial center of the conduit. Above that height the contact material becomes substantially uniformly distributed over the lateral cross section of the conduit, 4By introducing the hydrocarbon liquid feed peripherally into the lift conduit, particularly from opposed inlets, and into engagement with the upwardly moving contact material approximately at or above the level at which the contact material is substantially uniformly distributed over the cross section of the conduit good distribution of liquid on the contact material is obtained, as well as in the like introduction of the liquid hydrocarbons into the lower portions of the lift wherein the liquid feed engages relatively high concentrations of the contact material.

By operating in accordance with the present invention, as in the operation described in the prior application above referred to, the coke formed as a result of subjecting the liquid hydrocarbons to the high temperatures prevailing in the vicinity of the lift conduit and the transfer hop-per therebelow, is deposited in OI' QI). QQlltact material that is in positive upward motion and which can be subjected to regeneration as required, thereby precluding the accumulation of interfering quantities of coke deposit within the lift hopper, as on the exposed walls thereof or on any stagnant or relatively slower moving contact material that may be present in the hopper.

In typical procedures directed to the preparation of a charge stock for catalytic cracking, a bottoms fraction of crude oil or other high boiling fraction containing heavy ends which are not vaporized at the prevailing heating tempera ture, may be sent from the preheating furnace to a flash distillation zone, providing a vapor efiu= ent and a high boiling liquid fraction. The syse tem and operation of the present invention are advantageously adapted to the handling of both the liquid and vapor products from such flash distillation Zone. Conveniently such vapor prod ucts may be employed as all or part of the lifting fluid for the granular contact mass, while the liquid hydrocarbons are introduced directly into the lift conduit on the moving contact mass as above indicated. The vapor introduced into the transfer hopper for lifting or assisting in lifting of the granular solid contact material therein is; of course, not limited to such vaporous efiluent from flash distillation, and may be any gas or vapor not incompatible with hydrocarbons, but is preferably Vhydrocarbon vapor and/or steam. When hydrocarbon vapors are employed as lifting fluid or to assist in lifting the granular catalyst or other contact mass, such vapors may comprise all or a part of the vaporous effluent from a tar separator or other flash distillation apparatus. The liquid hydrocarbons may com prise the non-vaporized fraction from flash distillation, preferably free from tars as such and from undesirable salts present in tar residues. Alternatively the liquid feed may be composed in whole or part of heavy liquid separated from products of cracking, either recycled from the particular cracking operation or from some other source.

The operation of the novel features of the invention will be understood and other advantages thereof appreciated from the description which follows, read in connection with the accompanying drawings illustrating one form of apparatus that may be employed in practice of the invention, wherein:

Figure 1 is a schematic representation in ele vation of va hydrocarbon conversion system ern-A ploying a lift conduit for elevation of catalyst or other contact material, particularly illustrating the arrangement of the lift conduit and the processing or treating vessels directly associated therewith;

Figure 2 is a partial view in vertical section of the transfer hopper and a portion of the lift conduit associated therewith; and

Figure 3 is a plan view taken along the line 3 3 of Figure 2.

Referring now particularly to Figure l, there is shown a transfer hopper i, into which catalyst or other contact material is continuously admitted through a run down conduit 2, to form a bed within the hopper maintained at a substantially constant level as indicated at 3. Rising vertical-- ly from the transfer hopper l is a lift conduit 4, having its inlet end, in the illustrated embodiment, below the maintained bed level indicated at 3.

Thev lift conduit Lextends for a substantial dis-A tance above the top of the hopper l and has its upper terminus within a separating or disengaging vessel 5, which vessel is provided with a discharge conduit 6 at or near the bottom thereof.

The conduit 6, in the embodiment shown, discharges into a reactor or processing vessel which in turn is connected to a regenerating vessel or kiln 8 by means of a conduit il. By the arrangement described, accordingly, catalyst or other contact mass is continuously circulated from the bed in the transfer hopper I upwardly through the lift conduit 4 discharging into the vessel il, and then passes through a downward path including conduits E, 9 and 2 and the vessels I and 8. in returning tothe hopper I.

As better shown in Figure 2, the lift conduit 4 is surrounded by a concentric sleeve or housing' I0, which terminates at its lower end approximately at or near the bottom periphery of the lift conduit 4f There is thereby formed between the outer wall of conduit 4 and. the inner wall of sleeve I0 an annular chamber II which is open at its al vapor inlet, as indicated at I5, for reasons f which will hereinafter appear.

Referring particularly to Figures 2 and 3, it will be seen that conduit l, at a level intermediate the ends thereof, is surrounded by an annular' manifold I5, communicating with the interior of the lift conduit by a plurality of branches I1 passing through ports provided in the wall of the conduit. Preferably the branches I'I are slanted upwardly and in the direction of movement of the contact mass through the lift conduit li. A liquid supply line I 8 communicates with the manifold I6 for furnishing liquid hydrocarbons thereto for distribution into the conduit 4 by means of the branches I1.

A discharge line I9 communicates with the upper portion of the vessel 5 above the outlet of conduit 4 therein, to carry off vapors separated from the granular mass. The discharge line I9 communicates through a branch line 2t! with the reaction or processing vessel 1, through which all or a portion of the vapors in line IS may bc brought into the vessel 1.

In the illustrated embodiment the vapors are brought into the top of the vessel 1 and passed downwardly concurrently with the solid granular 5 contact mass gravitating therethrough, and the vessel 'I is provided near the bottom thereof with a disengaging section 22 wherein vapor products are again separated from the granular contact material and are withdrawn from the vessel by means of a vapor discharge line 23. It will be understood, that the oil vapors may be passed upwardly through vessel 1, ii" desired in countercurrent contact with the descending bed of contact material therein.

Below the disengaging section 22, the processing vessel 1 is provided with a purge section 24, which may be in the form of a tube sheet having depending downcomers. The purge section is in communication with a vapor supply line 25 for admission of steam or other inert gas into Vessel 1 for purging the contact material therein prior to its discharge from the vessel. The conduit 9 between the vessels 1 and s operates as a seal leg to prevent admixture of incompatible gases or vapors between these vessels, a small amount of an inert gas being flowed into the leg for that purpose, which may be a portion of the gas introduced through line 25 or separately introduced to ow in the leg 9 in appropriate direction de- 6 pending upon the pressure relation of the bottom portion of the vessel 'I and the top of the vessel 8.

The regenerating vessel 8 may be of any known or desired construction. In the embodiment shown, the regenerating gas is introduced at an intermediate point in the vessel through line 25 and iiows in both directions from the point oi introduction so that gases and vapor products formed as a result of combustion of coke are separately discharged at the top and bottom of the vessel respectively through lines 21 and 28.

In the operation of the embodiment thus far described, the lift vapors, such as steam and/or hydrocarbon vapors are introduced at the required pressure and in required quantity through line I4 into the annular zone II between the sleeve and the lift conduit. These vapors ow downwardly in the annular zone II and issue through the bottom I2 of that zone as an annular stream which ows to a level somewhat below the lower end of conduit 4. The vapors then reverse their direction of ilow and pass upwardly to the lift conduit 4. In doing so the vapors contact granular material from the bed in hopper I which lie in the vapor path adjacent the lower ends of sleeve I0 and'conduit 4, causing the granular material to pass beneath the lower periphery of conduit 4 and upwardly into that conduit. The granular material is then impelled upwardly in the conduit 4 by the vapors passing into and through that conduit, and is discharged from the upper end of the conduit into the disengaging vessel 5. Because of the expanded cross section of the vessel 5, the vapors discharged therein from conduit 4 lose velocity to the extent that the granular material is no longer supported by the vapors and settles out therefrom to accumulate as a bed in the vessel 5.

In the illustrated embodiment of Figure 2, hydrocarbons in liquid state are introduced into contact with the upwardly moving granular material in conduit 4, at a level some distance above the inlet to the conduit, at which level the contact material has become uniformly distributed over the cross section of the conduit. Thus, as shown the liquid hydrocarbons are introduced through supply line I8 into the distributing manifold I6, entering the interior of conduit 4 through branch lines I1 to contact the granular material ascending therein. Although four such branches I1 are shown, it will be understood that a larger or smaller number may be provided, preferably paired and opposed, so that the liquid hydrocarbons are brought into contact with the ascending stream of granular material /from opposite directions directed generally toward the center of the conduit. By slanting the ports upwardly in an inward direction the discharge of particles of granular material or nes thereof into the branches I1 is avoided. Y

Liquid hydrocarbons thus introduced through the line I8 and associated manifold into the lift conduit 4 are uniformly distributed in and on the upwardly moving mass of granular contact the top and bottom of the conduit 4. It is preferred, however, to locate the liquid introducing means at a point suiciently below the outlet of conduit 4, such that complete distribution of the liquid hydrocarbons on the granular contact material and adsorption therein is assured, so that no non-adsorbed liquid as such is discharged into the vessel 5. The level at which complete adsorption of the liquid which is not vaporized by Contact with the granular material is obtained will, of course, depend upon the temperature diierential between the contact material and the liquid hydrocarbons as well as on the adsorbency and relative flow rates of liquid and ,granular material. As a general rule, in practical operation, however, the point of liquid introduction should be no higher than about within, Lio feet of the tcp of the lift conduit 4.

To prevent upward iiow of hydrocarbon lift vapors through the bed of catalyst or other contact material in the hopper toward the space above the catalyst level 3, a gas pressure may be maintained above that level substantially equal to or siightiy above the pressure of the vapors at the outlet l2 of the annular chamber. For this purpose seal gas, which may be steam or other inert gas, admitted into the catalyst inlet leg 2 may be introduced at a suitable pressure so iat a portion of the gas ows concurrently with the catalyst and down that leg, entering the space above the catalyst level in the hopper. Alternatively or in addition, such seal gas might be introduced directly into the hopper above the catalyst level by means of the valve-controlled inlet iine i5. The use of steam for this purpose has the advantage of providing at least a portion of the steam that may be desired to be employed as process steam added to the hydrocarbon conversion reaction.

The vapors entering the lift conduit 4 together with vapors formed in that conduit by vaporization and conversion of the liquid feed introduced through line I8 are discharged together with the catalyst into the disengager vessel 5. Any liquid hydrocarbons that are not vaporized in the lift conduit will be completely adsorbed by the catalyst, and will be largely vaporized or converted by remaining in contact with the catalyst in the vessel 5, during gravitation of the catalyst therein and its discharge through the conduit 6. A portion of the vapor products disengaged from catalyst at the top of the lift may pass downwardly with the catalyst bed in the vessel and be discharged into the vessel 'l by means of conduit S. All or part of the hydrocarbon vapors discharged through line I9 are brought into the reactor 'l by means of branch line 2|, and are subjected to further conversion in contact with the catalyst in that vessel. Unvaporiaed liquid hydrocarbons, if there are any, carried by the catalyst into the vessel in adsorbed state, will also be vaporized and converted in the reactor 1. The total vapor conversion products and unconverted vapors are withdrawn from the reactor 'I through line 23 from which they flow to apparatus for separation into desired fractions and further processing as required.

The catalyst continuing its descent in the vessel 1, and below the disengaging Ameans 22, is l subjected to purging to remove adsorbed vapors by means of steam or other inert gas admitted through line 25, and the purged catalyst is then discharged into the regeneration kiln 8. In that kiln the catalyst is contacted with an oxygen- ,interfering with the lifting containing gas to effect combustion of coke in the catalyst, which raises the catalyst in temperature and stores sensible heat therein, to be subsequently employed for vaporization of liquid hydrocarbons, heating of hydrocarbon vapors to reaction temperature, and for maintaining the endothermic heat of reaction required in the conversion of the hydrocarbons.

In the embodiment illustrated in Figure 2, an auxiliary vapor inlet line is shown at 3|, operative to pass vapors upwardly through the catalyst bed. In employing this arrangement, these vapors admitted through line 3| at a comparatively low velocity merely serve to reduce resistance in the catalyst bed below the lift conduit 4 so that the catalyst is more readily picked up by the annular stream discharged into the bed through sleeve I0. The vapors admitted through line 3| mingle with the vapors discharged from the annular chamber passing together upwardly into the lift conduit 4 and eiTecting elevation of the granular contact material engaged by these vapors. By regulating the rate and quantity of vapors admitted respectively through lines I4 and 3| eicient control of the circulation rate of the contact material can be maintained. The vapors introduced through lines |4 and 3| may be of the same or different composition; for instance steam may be admitted through one of these lines and hydrocarbon vapors through the other. The line 3| may be an open ended pipe or may be provided with a diffuser head of suitable design. As shown at 32, the discharge outlet of the pipe may be provided with a suitable baille or screen to prevent granular material from falling into the pipe.

As in the embodiments described in the prior application referred to, the introduction of the more readily cokeable liquid hydrocarbons into initial contact with the catalyst or other granular contact material takes place at a point that the granular material is already flowing positively upward within the lift conduit, thereby avoiding the possibility of undesired coke accumulation within the hopper and rendering unnecessary the elaborate precautions that might otherwise be required to safeguard aga-inst the building up in a comparatively short period of an accumulation of coke in the hopper to an extent operation. By bringing the liquid charge into the lift conduit peripherally and from opposed directions, uniform distribution of the liquid by and adsorption in the solid contact mass is assured, without causing substantial deflection of the catalyst toward opposite Walls of the lift conduit, by the force oi the liquid stream.

To avoid'possibility oi liquid deposition with accompanying coking in the vessel 5, the quantity of liquid introduced into the lift conduit should be no greater than that which can be vaporized by and/or adsorbed in the catalyst over the path of travel of the catalyst between the point of liquid introduction and the top of the lift. In practical operation, however, the quantity of liquid introduced will be governed largely by the heat content of the catalyst stream, the heat content of the hydrocarbon stream, and the desired reaction temperature. For this reason the amount of liquid in such practical operations generally should not exceed about 1/3 of the catalyst volume and preferably should not be in excess of 1A; of the catalyst volume. The quantity of vaporized hydrocarbons charged in addition to the liquid hydrocarbons, will depend upon the esagero operating conditions established for the principal reaction zone (compact moving bed reactor), including the selected catalyst to total hydrocarbon ratio as one of these conditions. Such additional vaporized hydrocarbons may be introduced, entirely or only in part into the lift conduit, as previously described; to serve as lifting vapors, and additional hydrocarbons may be brought into the compact bed reactor, as by means of a line 33, if needed to make up the required hydrocarbon to catalyst ratio.

The chamber should be maintained at a sufficient pressure above atmospheric so that the vapor products discharged through line i9 can be sent into the processing vessel i and through that vessel with accompanying pressure drop, to be discharged through line 2-3 at a pressure such that the vapor efliuent can be sent to further processing without necessitating pressure boosting. charge line 23 should be in the order of at least about 6 p. s. i. g. Efficient and smooth operation of the lift with adequate mass flow rate of solids to obtain adsorption of the liquid hydrocarbons contacted therewith, can be obtained under lift operating conditions providing a pressure drop of about 1 to about 12 p. s. i. g. in the lift conduit 4, so that the pressure in hopper I immediately below the conduit e must be sufficient to take care of the pressure drop in the lift conduit, in lines I s and 20, through the bed in vessel l and to provide the desired discharge pressure at line 23. The required pressure in hopper l will determine the pressure of introduction of vapors through line M or through that line and line 3l if the latter is employed.

Instead of separately admitting vapors and catalyst from the vessel 5 into the vessel l, if desired, the vapors as well as the catalyst may be permitted to flow through the conduit 5 into the processing vessel 'l'. In such case the conduit 6 may be of suflicient diameter such that it will be only partly lled by the discharged catalyst fiovving therethrough.

As a general rule, practice of the invention does not necessitate a departure from the usual processing conditions used in conventional systems for carrying out hydrocarbon conversion reactions, for instance those employing gravitating compact beds of catalyst or other contact mass, as in catalytic cracking of hydrocarbons to gasoline, catalytic reforming of naphthas to products of improved quality, or corresponding non-catalytic operations vwherein the granular contact mass is relied upon chiefly as a heat source.

As catalysts for hydrocarbon cracking operations there may be employed the known siliceous and other cracking catalysts including acid-activated clay pellets or synthetic silica-alumina in the form of cylindrical or spherical pellets (beads), of a size range designated as granular as distinguished from finely divided powders of up to 10G-200 'mesh size. S-uch granular catalyst or other solid contact mass is characterized by the property of forming compact beds through which gases and vapors can be passed upwardly at practical operating velocity without signincantly disturbing the bed, as distinguished from nnely divided powders which are irnpelled or form fluidized beds by passage of gases or vapors therethrough at considerably lower velocity. The granular catalyst or other contact mass employed in practice of the present invention should generally be of a size greater than about Generally pressure at the disio .05 inch in major dimension, and up to about 0.5 inch.

Example The following example illustrates a typical operation in the practical adaptation of the invention as applied to processing about 2000 barrels of oil per day as fresh feed. The arrangement is based on the use of a unit comprising a i2 inch diameter lift conduit of about 200 feet in height.

An East Texas crude oil is fractionated and the bottoms fraction constituting about 40% of the total crude separated. This fraction, having a gravity of 23.7 A. P. I. and an initial boiling point of 425 F., 80% boiling up to l0l4 F., is admitted at appropriate temperature to a flash vaporization zone, such as a conventional tar separator, operating at a temperature of 850 F. at a pressure of about 17.5 p. s. i. gauge, steam being admitted to the zone at the rate of about 24.7 pounds per barrel of oil charged. All of the vaporized hydrocarbons and steam withdrawn overhead are sent to the lift hopper to operate as vapor lift medium, entering the hopper at about the flash distillation temperature. The non-vaporized hydrocarbons, constituting about 37.5% of the oil charged to the iiash distillation zone, are removed as a bottoms fraction and sent to a vacuum flash distillation Zone to remove the heavy tars Aand salt contaminants. The vacuum distillation zone is operated at a pressure of about mm. of mercury and steam is added thereto at the rate of approximately 2.9 pounds per barrel of oil. About one-fifth of the original 40% bottoms fraction of the crude oil, is discharged as tar bottoms from the vacuurn distillation zone, while the overhead therefrom is permitted to condense and pumped as liquid feed (23.4 A. E. I. gravity) to the lift through line I8. On the basis of an original 2,000 barrels per day charged to the flash. distillation zone, this will provide for introduction into the lift about 1250 barrels of hydrocarbon vapors at the stated temperature plus the added steam, and about 350 barrels of liquid feed at about 650 F. Freshly regenerated synthetic silica-alumina bead catalyst at about 100 F. enters the lift at a rate giving a weight ratio of catalyst to oil of 6 to 1.

With the average reaction temperature in the gravitating bed reaction Zone at 850 F., average pressure of 10 p. s. i. gauge, and a space rate of 7 pounds of oil per pound of catalyst in the reaction zone per hour, the products are as It will be understood that the operating conditions above set out are merely illustrative and may be varied over a fairly wide range. Thus, the regenerated catalyst will usually be admitted to the lift at a temperature above that of the oil, say at about 900-1100 F. to take advantage of the heat content of the catalyst. At high catalyst to oil ratios the liquid feed may be admitted to the lift at temperatures as low as 40G-500 F., while in some cases the liquid feed may be at temperatures as high as 900 F., or above. In certain 11 operations, the entire liquid bottoms from flash distillation may be sent directly to the lift without removal of the heavy tars. Various other sources of liquid feed may be used, such as slop oil from a lube refining operation.

Since the vaporizatio'n of the liquid hydrocarbons takes place within the lift conduit, the vapors thus produced do not signicantly inuence the catalyst circulation rate. Accordingly, uncontrolled changes in catalyst flow rate that might result from variation in the nature or condition of the liquid feed, if it were vaporized in the lift hopper, are avoided.

Obviously, many modifications and variations of the invention as hereinbefore set forth may be made Without departing from the spirit and scope thereof and therefore only such limitations should be imposed as are indicated in the appended claims.

I claim as my invention:

l. The method o processing a liquid hydrocarcon charge containing components boiling above the range of gasoline, which comprises heating such a charge by contacting the same in liquid state and in controlled quantity with hot granular adsorptive contact material, said granular material being at a temperature higher than said charge and directly transferring heat contained therein to said charge eiecting at least partial vaporization of said charge, the contacting of the charge with said granular material being eiected by admitting the liquid charge peripherally into a laterally confined upwardly. moving stream of said granular material impelled by an upwardly flowing gasiiorm medium compatible with hydrocarbons, limiting the quantity of` liquid hydrocarbons thus contacted with the granular material to an amount such that any oi' such hydrocarbons` not vaporized thereby are adsorbed in the granular material during upward travel of ing the same in liquid state with hot catalyst at a temperature capable of causing coking of said liquid hydrocarbons, said contacting being eiected by introducing the liquid hydrocarbons peripherally into a laterally confined upwardly moving stream comprising said granularv catalyst impelled by an upwardly flowing gasiform medium compatible with hydrocarbons, limiting the quantity'of liquid hydrocarbons thus introduced so that any unvaporized hydrocarbons are adsorbed in the catalyst and no unadsorbed liquid hydrocarbons as .such are carried by said stream beyond the point of discharge of said stream, discharging the catalyst from said stream to terminate upward movement of said catalyst, thereafter passing the catalyst by gravity as a compact bed through a conversion zone, and contacting with said bed of catalyst in the conversion zone at least a portion of the hydrocarbon vapors formed from said'liquid hydrocarbonsv toY effect 12 desired conversion of these hydrocarbon vapors under catalytic conversion conditions. l

3. The method in accordance with claim 2 wherein said impelling gasforin medium cornprlses hydrocarbon vapors.

4. The method in accordance with claim 2 wherein said liquid hydrocarbons are introduced into contact with said catalyst as paired liquid streams from opposing directions.

5. The method in accordance with claim 2 wherein said catalyst is one having cracking activity and said catalytic conversion conditions are selected to effect cracking of said hydrocarbon vapors in said conversion zone.

6. The method in accordance with claim 2 wherein said confined upwardly movingstream comprising granular catalyst contains the catalyst in substantially uniform distribution over the transverse cross section of said stream at the locus of introduction of said liquid hydrocarbons into said stream.

'7. The method in accordance with claim 2 wherein said liquid hydrocarbons comprise condensate of above gasoline boiling range and separated from products of a catalytic cracking operation. l

8. In the catalytic cracking of hydrocarbons in contact with granular catalyst, the method of handling a hydrocarbon` charge stock containing higher boiling hydrocarbons which do not vaporize at normal pressure below the coking temperature thereof, which comprises subjecting such a charge stock to iiash vaporization thereby obtaining a vapor overhead and an unvaporized liquid hydrocarbon fraction, introducing at least a portion of said vapor overhead in vapor state and under pressure into a body of hot freshly regenerated cracking catalyst to cause elevation of catalyst thereby, impelling thus elevated catalyst by these hydrocarbon vapors through an elongated laterally conned vertical path, introducing at least a portion of said liquid hydrocarbon fraction in liquid state as a lateral stream into said confined path and into contact with the upwardly moving hot catalyst in said path, said catalyst being at a temperature suiilciently high to cause coking of the liquid hydrocarbon fraction contacted therewith, thereby vaporizing the liquid hydrocarbons while in said path and adsorbing on the catalyst any liquid which is not thereby vaporized, any coke formed as a result of such contacting with liquid hydrocarbons being deposited in the catalyst, discharging the thus contacted catalyst at the upper end of said confined path, passing the discharged catalyst -as a compact gravitating bed through a vapor cracking Zone maintained under catalytic cracking conditions, and contacting hydrocarbon vapors formed in and discharged from said confined path with said gravitating bed of catalyst to effect catalytic cracking of said vapors and deposition of coke in said catalyst, transferring the coke-containing catalyst from said vapor cracking zone into a regeneration zone, burning coke contained in said catalyst in said regeneration zone thereby heating the catalyst to required temperature, and discharging the hot Yfreshly regenerated catalyst for further contact with and elevation by said vapor overhead from said ash vaporization.

9. The method in accordance with claim 8 wherein said liquid hydrocarbon fraction is introduced into said confined path as a plurality of streams directed inwardly toward the radial center of said path.

10. 'Ihe method in accordance with claim 8 wherein said liquid hydrocarbon fraction is introduced at a level along the vertical extent of said confined path at which the catalyst is substantially uniformly distributed over the transverse cross-section of said path.

11. The method of treating hydrocarbon oils which comprises engaging hot granular cracking catalyst with a vapor stream comprising normally liquid hydrocarbons in vaporized state, to effect elevation of said catalyst into and through an elongated laterally confined vertical path under the impelling inuence of said vapor stream, introducing hydrocarbon oil in liquid state peripherally into said vertical path from opposing directions and at a level along the vertical extent of said path wherein the catalyst therein is substantially uniformly distributed over the lateral cross-section of said path, transferring heat from said catalyst to the liquid oil to effect vaporization of said oil within said path, discharging the catalyst and vaporized oil from said path, and further contacting the vaporized oil with a ycompact downwardly moving bed of the thus discharged catalyst under catalytic cracking conditions to effect further conversion of said oil.

12. The method of cracking of hydrocarbon oils with granular cracking catalyst which comprises passing hydrocarbons solely in Vapor state into contact with a compact gravitating bed of such catalyst present in a cracking zone at a temperature supplying heat for the cracking of such hydrocarbons, discharging a vapor eiiluent comprising cracked hydrocarbon products from said cracking zone, separately discharging used catalyst from said cracking zone and containing therein carbonaceous deposit from cracking of hydrocarbons, regenerating the catalyst thus discharged by combustion of carbonaceous deposit therein, thereby raising the temperature of said catalyst and storing sensible heat therein, passing the hot freshly regenerated catalyst to a lifting zone, contacting the catalyst in said lifting zone with a vapor streamy under pressure effecting elevation of catalyst from said lifting zone into a laterally confined vertical path, and continuously impelling the catalyst upwardly in said vertical path by concurrently owing said vapor streams past the catalyst in said path; fractionating the vapor eiliuent from said crack ing zone and separating from the fractionated products a condensed liquid hydrocarbon fraction higher boiling than gasoline; introducing the condensed liquid fraction in liquid state, without intermediate heating, into said vertical path and into direct contact with the hot freshly regenerated catalyst moving upwardly in said path thereby cooling said catalyst and heating said liquid fraction to a temperature eiecting at least partial vaporization of said liquid fraction, said liquid fraction being introduced peripherally from opposed directions as owing liquid streams at an intermediate point in said vertical path at which said catalyst is substantially uniformly distributed over the transverse cross section of the path, to eiect uniformv'distribtion of liquid on the catalyst and complete adsorption of any unvaporized liquid in the :catalyst: thereafter passing said catalyst to saldi-first named cracking zone to form a compact bed therein and contacting the compact bed of catalyst with hydrocarbons in vapor state formed from vaporization of the liquid fraction in said path.

WILLIAM W. WEINRICH.

REFERENCES CITED The following referencesv are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 2,432,344 Sinclair Dec. 9, 194'? 2,437,222 Crowley et al. Mar. 2, 1948 2,463,623 Huff Mar. 8, 1949 2,487,961 Angell Nov. 15, 1949

Claims (1)

1. THE METHOD OF PROCESSING A LIQUID HYDROCARBON CHARGE CONTAINING COMPONENTS BOILING ABOVE THE RANGE OF GASOLINE, WHICH COMPRISES HEATING SUCH A CHARGE BY CONTACTING THE SAME IN LIQUID STATE AND IN CONTROLLED QUANTITY WITH HOT GRANULAR ADSORPTIVE CONTACT MATERIAL, SAID GRANULAR MATERIAL BEING AT A TEMPERTURE HIGHER THAN SAID CHARGE AND DIRECTLY TRANSFERRING HEAT CONTAINED THEREIN TO SAID CHARGE EFFECTING AT LEAST PARTIAL VAPORIZATION OF SAID CHARGE, THE CONTACTING OF THE CHARGE WITH SAID GRANULAR MATERIAL BEING EFFECTED BY ADMITTING THE LIQUID CHARGE PERIPHERALLY INTO A LATERALLY CONFINED UPWARDLY MOVING STREAM OF SAID GRANULAR MATERIAL IMPELLED BY AN UPWARDLY FLOWING GASIFORM MEDIUM COMPATIBLE WITH HYCARBONS, LIMITING THE QUANTITY OF LIQUID HYDROCARBONS THUS CONTACTED WITH THE GRANULAR MATERIAL TO AN AMOUNT SUCH THAT ANY OF SUCH HYDROCARBONS NOT VAPORIZED THEREBY ARE ADSORBED IN THE GRANULAR MATERIAL DURING UPWARD TRAVEL OF THE GRANULAR MATERIAL, DISCHARGING SAID GRANULAR MATERIAL FROM THE IMPELLING INFLUENCE OF SAID GASIFORM MEDIUM TO TERMINATE UPWARD MOVEMENT OF SAID GRANULAR MATERIAL, THEREAFTER PASSING SIAD GRANULAR MATERIAL, AS A COMPACT GRAVITATING BED THROUGH A LATERALLY CONFINED HYDROCARBON PROCESSING ZONE, AND CONTACTING SAID BED OF GRANULAR MATERIAL WITH HYDROCARBON VAPORS TO BE PROCESSED AND INCLUDING VAPORS FORMED FROM SAID LIQUID CHARGE.

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