US2886520A - Method and apparatus for contacting liquid with granular contact material - Google Patents

Description

M y 1959 J. J. CICALESE 2,886,520.

A METHOD AND APPARATUS FOR CONTACTING LIQUID WITH GRANULAR CONTACT MATERIAL I 2.Sheets-Sheet 1 Filed Dec. 2, 1957 MMD-P/IZSE OVA/P65 cnrflzysr 1V6 VAPd/P STEAM/ IN V EN TOR.

\AALW'MM.

CICALESE METHOD AND APPARATUS FOR CONTACTING LIQUID WI ggssaszo May 12, 1959 GRANULAR CONTACT MATERIAL 2 Sheets-Sheet 2 Filed Dec. 2, 1957 9 R. w M] mm m& J J m I w A SKIN. MM

ATTORNEY United States Patent METHOD AND APPARATUS FOR CONTACTING WITH GRANULAR CONTACT MA- Julius .l. Cicalese, Drexel Hill, Pa., assignor to Houtlry Process Corporation, Wilmington, Del., a corporation of Delaware Application December 2, 1957, Serial No. 700,217 8 Claims. (Cl. 208-467) This invention relates to hydrocarbon conversion systems and particularly to systems in which mixed-phase hydrocarbons are contacted with granular contact material to carry out the desired conversion.

Typical of the conversion processes and systems to which the present invention is applicable are the cracking of relatively high-boiling liquid hydrocarbons to gasoline, using granular, adsorptive, hydrocarbon cracking catalyst, and the viscosity breaking or coking of such hydrocarbons, using relatively catalytically-inert granular solids of the type known as heat carriers. The invention is in the nature of an improvement on the method and apparatus for contacting liquid hydrocarbons with granular contact material disclosed in co-pending application, Serial No. 431,376, of Willis I. Cross, In, filed May 21, 1954 for Method for Contacting Liquid with Granular Contact Material.

The use of higher boiling fractions of crude oil, such as tar separator bottoms, reduced crudes, heavy fuel oil and the like, as charging stock for the preparation of gasoline and/or light fuel oil presents difiiculties because of the ease with which such fractions thermally decompose to form coke, whether or not volatile cracked products also are formed. For example, many of such fractions coke up the tubes of heating furnaces when heated to temperatures of 850 F. or higher. Hence, even if these fractions are vaporizable at temperatures of 900 F. to 1000 F., they cannot be handled as vapor, because such practice would result in frequent shut-down of the heating equipment. For this reason, it has been a practice to contact such charging stocks in liquid phase with hot granular contact material, so as to convert the liquid hydrocarbons to volatile products, with attendant formation of a hydrocarbonaceous deposit, including heavy, nonvaporizable hydrocarbons, on the contact material. The hydrocarbonaceous deposit on the contact material generally further decomposes during the conversion period to form additional volatile hydrocarbons and coke, the latter being removed by combustion with oxygen-containing gas during a subsequent regenerative operation.

However, when the aforementioned charging stocks and other liquid charges, such as, virgin or cracked light gas oils and naphthas, contact the reactor walls and other metallic surfaces within the reactor which are at hydrocarbon cracking temperatures, the resulting cracking reactions tend to produce a cumulative deposit of coke on such surfaces. Such deposits accrete above the level. of solid contact material within the reaction vessel and from time to time break ofi as large pieces or chunks of coke fall into the moving mass of contact material. These chunks of coke thereafter interfere with the proper move- I ment of the contact material, even to the point of stop- T. Savage. It involves the projection of liquid hydro-- carbons toward a curtain of free-falling particles of granular contact material, which curtain has such density and thickness as to intercept substantially all the liquid hydrocarbons directed thereto.

In the aforementioned co-pending application, Ser. No. 431,376 there is disclosed a liquid feed nozzle comprising a cylindrical member provided with internal sloping vanes disposed at a common level located at least one diameter above the lower end of the cylindrical member and disposed at such angle to the axis thereof that a mixed-phase stream passing through the nozzle is whirled about such axis so as to concentrate the heavier liquid portion of the stream along the inner wall surface of the cylindrical member. Thus, in passing through the vaned portion of the nozzle the mixed-phase stream is centrifugally separated into a liquid portion which thereafter flows as a circumferentially-complete annular confined stream along the remaining portion of the cylindrical member, and a gaseous portion which flows centrally through the substantially liquid-free hollow center of the discharging liquid stream.

The angularity of the internal vanes is such that the whirling liquid component, in leaving the vaned region of the nozzle, will not impinge upon the lower inner-wall surface of the nozzle with sufficient force to effect any substantial atomization of the liquid. Consequently, upon discharge from the lower end of the liquid feed nozzle, the liquid component discharges as a rapidly-rotating hollow annular stream which, upon leaving the lower perimeter of the confining surface provided by the cylindrical member, is cast outwardly and downwardly as an expanding stream of dispersed liquid droplets. These liquid droplets are intercepted by an annular, free-falling curtain of granular contact material which, in the manner disclosed in said co-pending application, descends concentrically around and below the liquid feed nozzle to the surface of a compact moving bed of such contact material maintained within the conversion zone at a constant level some distance below the liquid feed nozzle.

In order to provide a flexibility of operation which will assure a velocity within the nozzle sufficient to effect the desired centrifugal separation, and to discharge the liquid portion with sufficient centrifugal force to attain the proper liquid dispersion and interception by the falling curtain of contact material, it is necessary to have a proper proportion between the circumference of the surface which confines the annular rotating liquid stream and the remaining cross-sectional area of the hollow cylindrical stream which is available for the passage of the gaseous material. It is especially desirable that the gaseous material be discharged from the lower end of the liquid feed nozzle at a velocity within a pre-selected range. Such velocity, for example, is preferably great enough to provide the proper dispersion of liquid droplets and yet not so great as to cause the liquid droplets to forceably penetrate or break up the falling curtain of granular material.

It has been observed that, within certain limits, there is a relatively Wide range in the respective quantities of vapor and liquid which may be handled simultaneously in a vaned nozzle of the type referred to herein, and that the proportions of vapor and liquid may vary independently, consistent with satisfactory nozzle performance, regardless of substantial changes in process conditions in the hydrocarbon conversion unit as a whole. It was found that the maximum amount of liquid hydrocarbons that can be handled efiiciently is a function of the circumference of the cylindrical member comprising the body portion of the nozzle. Expressed in terms of nozzle diameter, the ratio of liquid flow in cu. ft./sec. to nozzle diameter in inches should be less than 0.040, and preferably less than about 0.0365, regardless of the velocity of accompanying vapor. It was noted also that with an acceptable ratio of liquid flow to path diameter the operable range of vapor velocity was approximately to 75 feet per second, and preferably about 35 to 65 feet per second.

Since at least a certain minimum vapor velocity is essential for efiicient operation of a given nozzle designed to handle the desired quantity of liquid, in those cases where the normal vapor velocity is below such minimum either additional vapor, such as steam, may be added upstream of the nozzle, or the flow area in the region of the nozzle wherein the rotary motion is imparted may be suitably restricted.

In order to achieve such restriction within the nozzle a central plug may be provided within the vaned portion of the nozzle. A reduction of the total flow area may thereby be obtained to increase the vapor velocity to a magnitude sufiicient to maintain the desired liquid flow.

While the eificiency o'f aforementioned type of nozzle has been satisfactorily demonstrated in cases where the nozzle did not exceed several feet in diameter, it has been found difificult to achieve the desired operating flexibility with liquid feed nozzles of larger size, such as up to about 4 :feet in diameter. The problem becomes especially acute when the larger size nozzles are employed with a charge stream having relatively low feed vaporization. In such cases, the relatively-large nozzle circumference required for the liquid portion of the feed stream necessitates the use of an extremely large central plug in order to obtain the required gas velocity. For example, it has been determined that a nozzle having a 46' ID. might require a 76% plug, that is, a central plug cutting off 70% of the flow area. Also, that a 38 ID. nozzle might require a 50% plug.

A principal object of the present invention, therefore, is to provide an improved nozzle design which will give the necessary distribution of liquid over the falling curtain of contact material while at the same time minimizing the size of the various nozzle elements in the interest of economy and ease of fabrication.

In accordance with the present invention the foregoing and other objects are attained by providing inner and outer concentric flow paths, each adapted to convey separate mixed-phase portions of the total charge stream, with control over the oil distribution between the two paths. The inner or central flow path conforms in general to that disclosed in the aforementioned application, Serial No. 431,376, while the outer flow path is in the form of an annulus surrounding the inner flow path. The annular flow path is similarly vaned so as to effect a comparable centrifugal separation of the gaseous and the liquid components of its portion of the total charge. Suitable proportioning of the total flow is effected in known man ner so that the desired flow characteristicsare achieved in each flow path, and provision is made for the intro duction of additional gaseous material, such as steam, into one or both of the separate streams prior to such centrifugal separation.

In one embodiment of the invention, the novel method is carried out by a nozzle comprising two elongated con centric cylinders adapted and arranged to provide a vaned nozzle within a vaned nozzle. At a location at least one diameter above the lower end of the inner cylinder there is positioned a central solid plug member which substantially restricts the flow area of the inner cylinder by as much as about 50%. At a common level within the an nular passageway formed between the-central solid plug and the walls of the inner cylinder there are a plurality of inclined vanes, so that the portion of the charge stream passing through the central cylinder is subdivided into a plurality of separate streams each flowing along a helical path throughout the vaned portion of the cylinder.

A second annular path, provided by the annular space between the two cylinders, receives the remaining portion of the total charge stream. At a distance of at least one diameter of the larger cylinder above its lower end a plurality of inclined vanes are provided Within the annular space, so that fluid flowing downwardly between the cylindrical members also is given a whirling motion by being subdivided into a plurality of helical flow paths while passing through the vaned portion of the larger cylinder. Thus, the nozzle formed by the inner cylinder is, in effect, the central restricting plug for the outer cylinder. Any additional restriction of the annular path between cylinders which may be desired is readily obtained by providing a collar about the outer circumference of the inner cylinder at the level where the annular space is provided with vanes.

Although, generally, it may be preferable to have the lower ends of the cylinders at the same level, such arrangement is not essential. Within practical limits, the inner nozzle may extend below the outer nozzle, or possibly slightly above.

An annular curtain of catalyst is caused to descend by free fall about the outer cylinder and be deposited upon the surface of a compact moving bed of such catalyst whose surface is maintained some distance below. The liquid components of the streams flowing through the inner and outer nozzles are caused to flow as hollow, circumferentially-complete rotating streams throughout the lower end portion of each nozzle flow path. At their level or levels of discharge the rotating cylindrical streams of liquid are directed outwardly and downwardly as sep arate concentric conical streams of dispersed liquid droplets. The central portion within the innermost liquid stream contains the gaseous discharge from the inner cylinder, and the annular space between the liquid streams receives the gaseous discharge from the outer cylinder. There is substantially no atomization of the liquid particles, and the gaseous material flowing through the annular passageway between the cylindrical members fiows in part downwardly through the dispersing cone of liquid particles moving outwardly and downwardly from the lower rim of the inner cylinder toward the falling curtain of solids.

For a fuller understanding of the invention reference may be had to the following specification and claims taken in connection with the accompanying drawings forming a part of this application in which:

Fig. 1 is an elevation view of a typical reactor to which the nozzle of the present invention may be applied, portions of the reactor being illustrated in partial section to show the arrangement of the nozzle;

Fig. 2 is an enlarged sectional elevation of the liquid feed nozzle; and

Fig. 3 is a plan view of the nozzle taken along the line 3-3 of Fig. 2.

In the drawings the invention is disclosed in connectron with the reactor of a typical hydrocarbon conversion system involving the use of granular contact material, such as catalyst. The catalyst gravitates within the reactor in the form of a compact moving bed comprising the main reaction zone, which bed is continuously replenished by confined compact moving streams of catalyst fed directly to the surface thereof and by catalyst introduced into the upper region of the reactor and deposited by free fall upon the surface of the bed in a manner hereinafter to be described.

Fig. 1 of the drawings shows a reactor vessel 11 constituting the conversion portion of a hydrocarbon conversion unit. The upper portion of vessel 11 is cut away to show an upper catalyst distribution or surge chamber and a lower reaction chamber, 12 and 13 respectively, separated by a horizontal tube-sheet 14.

The granular catalyst ranges in size from about 0.05 to about 0.5 inch in average diameter, and comprises freshly regenerated contact material supplied from a regeneration zone or chamber, not shown. The catalyst is introduced into the upper end of reactor 11 through catalyst inlet conduit 15 and is deposited upon the surface of a compact moving bed of catalyst 16.

The catalyst may comprise freshly regenerated solid hydrocarbon cracking catalyst, such as granular acidactivated montmorillonite clay, synthetic-silica alumina gel in pellet or bead form, or other solid refractory composition known to the art as suitable catalysts for the cracking of hydrocarbons.

The catalyst bed 16 is supported upon tube-sheet 14. The tube-sheet is provided with a circumferential row of elongated downcomers 17 having their upper ends set in the tube-sheet. The downcomers extend downwardly around the peripheral region of the reaction chamber 13. Catalyst is continuously withdrawn from the bottom of bed 16 and is passed as a plurality of compact moving streams through the downcomers 17 to the surface of a compact moving bed of catalyst 18 located at the bottom of the reaction chamber 13 and comprising the main reaction zone. The flow of catalyst through downcomers 17 is such as to maintain the surface of moving bed 18 at a relatively constant level regardless of variations in the flow of catalyst introduced by free fall, as aforesaid, or in the rate of catalyst discharge from the bottom of bed 18. Only a relatively minor portion of the total catalyst discharging from distributor bed 16 passes through downcomers 17, the purpose of the latter being primarily for bed level control.

In a manner known to the art, a description of which is not considered necessary for a complete understanding of the present invention, the catalyst comprising bed 18 catalyzes the desired hydrocarbon conversion and is subsequently discharged from the lower end of the reactor 11 through catalyst discharge outlet 19.

In order that the hydrocarbon vapors formed within the reaction chamber 13 may be prevented from migrating upwardly into the distributing chamber 12, and from the latter chamber upwardly through the catalyst inlet 15, an inert gaseous sealing medium, such as steam, flue gas and the like, is introduced into the upper region of chamber 12 through inlet conduit 21. The pressure within chamber 12 is maintained high enough to cause a constant flow of seal gas from chamber 12 to reaction chamber 13.

The arrangement of the liquid-vapor feed nozzle of the present invention is shown in elevation in Fig. l, and the details of the nozzle are more clearly illustrated in the enlarged views of Figs. 2 and 3. While the liquidvapor feed nozzle is independent of the means for discharging catalyst as an annular free-falling curtain surrounding the discharging gas and liquid streams, the present embodiment of the invention combines the catalyst and hydrocarbon feed means into a unitary structure for the purposes of mutual support and ease of fabrication and installation.

The nozzle in general comprises a plurality of hollow cylindrical members concentrically arranged, one within the other, to form a central or axial flow path surrounded by a plurality of annular flow paths.

Specifically, the nozzle comprises four elongated cylin drical members 22, 23, 24 and 25, numbered in the order of increasing diameter. The innermost cylinder 22 provides a flow path 26 for a mixed-phase stream of hydrocarbons, as does also the annular passageway 27 formed between cylinder 22 and its next adjacent cylinder 23. The annular space 28 formed between cylinders 23 and 24 is relatively narrow and provides an insulating space which may be used as a passageway for steam. The annular space 29 between cylinders 24 and 25 is relatively wide, and provides a passageway for a compact moving annular stream of catalyst withdrawn from the distributor bed 16. The upper end of outer cylindrical member 25 extends through an opening in the tube-sheet 14 and communicates with the catalyst bed 16. The top of cylinder 25 is flared outwardly and is covered with a grating 31 of such size and configuration as to freely pass catalyst from the distributor bed 16, while preventing the admittance of agglomerated masses of catalyst which might eventually clog the catalyst discharge gap at the lower end of annular passageway 29.

Separate hydrocarbon feed lines 32 and 33 extend downwardly through the upper end of vessel 11 and are joined, as by butt-welding, to the upper ends of cylinders 22 and 23, respectively. By appropriate valve control means, not shown, hydrocarbon feed line 32 introduces a portion of the total charge into the central passageway 26 provided by conduit 22, and hydrocarbon feed line 33 introduces the remaining portion of the charge into the annular passageway 27 formed between cylinders 22 and 23. It is to be understood, however, that provision may be made for introducing additional vaporous hydrocarbons into the upper region of the reaction chamber 13 at one or more locations above the surface of the reactor bed 18 through suitable vapor feed means, if desired.

Cylinder 24 extends upwardly through chamber 12 and through the upper end of vessel 11. A gas inlet line 34- communicates with the upper end region of annular space 28 through the external upper end portion of cylinder 24. Annular space 28 serves to insulate the hydrocarbon stream within annular space 27 from the high temperature catalyst stream flowing downwardly through annular space 29. Optionally, steam or other suitable gaseous material may be introduced through inlet 34 so as to flow downwardly through annular space 28 and be discharged into chamber 13 about the lower end portion of cylinder 23, thereby carrying ofr some of the heat from the wall surface of cylinder 24.

The lower end of cylinder 24 is at a level substantially higher than the lower end of cylinder 23, and has secured thereto a hollow frusto-conical skirt member 35 provided with radial spacers 36 which allow for differential expansion between cylinder 24 and the cylinder formed by members 23 and 33. Spacers 36 also serve to maintain concentricity between the cylindrical members.

As more clearly shown in the enlarged drawings of Figs. 2 and 3, cylinder 24 is provided at its lower end with an annular reenforcing ring 37, and the adjacent upper end of frusto-conical member 35 also is provided with an annular reenforcing ring 38, so that member 35 may be removably attached, as by bolts, to the lower end of member 24. A short cylindrical ring 39 is attached to and extends upwardly from the outer perimeter of ring 37 so as to form an annular catalyst-retaining trough 41 about the lower perimeter of cylinder 24.

A relatively short cylinder 42 concentrically surrounds frusto-conical member 35 and the lower end portion of cylinder 25, and is rigidly supported from member 35 by suitable means, such as radial fins or struts, not shown. Cylinder 42 is spaced outwardly from members 25 and 35 so as to form an upper annular gap 43 and a lower annular gap 44. Catalyst flowing downwardly through annular passage 29 is deflected outwardly by the mass of stagnant or nonmoving catalyst retained within the trough 41. In flowing outwardly beneath the lower end of cylinder 25, the catalyst forms an annular exposed surface of solids 45 through which gaseous material accompanying the catalyst along annular path 29 may be disengaged. The disengaged gas is discharged into chamber 13 through the annular passage or gap 43.

The lower ends of frusto-conical member 35 and cylinder 42 also are provided with annular reenforcing rings 46 and 47 respectively, to the underside of which are attached'inner and outer flat annulus rings 48 and 49 respectively. The inner periphery of annulus ring 48 is slightly spaced from the outer wall surface of cylinder 23 so as to form therewith a narrow gap through which gas flowing downwardly through annular passage 28 may escape into chamber 13. The opposed vertical edges of annulus rings 48 and 49 .are horizontallyspaced to pro- '7 vide the catalyst flow control gap 44. Catalyst flowing downwardly between members 35 and 42 discharges through gap 44 to form an annular free-falling curtain of solids.

As to the feed nozzles formed by cylinders 22 and 23, the innermost nozzle 22 is similar to that disclosed in the aforementioned application Serial No. 431,376 of Willis J. Cross, Jr. The nozzle comprises a central cylindrical plug member 51 surrounded by a plurality of inclined vanes 52. Three vanes, at an angular spacing of 120, have been found most satisfactory for general use. Although the vanes may be inclined at an angle to the horizontal in the range of about 2070, the best angle is one which will provide a rapid whirling of the mixed-phase stream of hydrocarbons sufiicient to form an annular rotating circumferentially-complete layer of liquid adjacent the lower inner wall surface of cylinder 22 and a central rapidly-rotating vapor stream having the characteristics of a cyclone, Without any substantial atomization of the liquid component. A vane angle of about 45 has been found quite satisfactory.

The cylinder 23 also is provided with inclined curved vanes 53 within the annular space 27. Cylinder 22, in efiect, acts as a central plug for cylinder 23, similar in function to plug 51. Although, conceivably, it might be desirable in certain cases to have vanes 52 and 53 oppositely inclined, so that the hydrocarbon streams rotate in oposite directions, for general use it is contemplated that the vanes will be inclined in the same direction.

The arrangement is such as to provide a nozzle within a nozzle. In each of the nozzle passages 26 and 27 the vanes are located at least one nozzle diameter, and preferably not substantially more than 1 /2 nozzle diameters, above the lower end of the nozzle. In the illustrated embodiment of the invention nozzle flow path 27 is unobstructed except for the vanes 53. However, it is contemplated that the flow path may be restricted along the vaned region by placing a sleeve of suitable wall thickness around the conduit 22. Such sleeve would then support the inner edges of curved vanes 53.

The nozzle of the present invention overcomescertain difiiculties inherent in the use of single, large-diameter nozzles for handling a mixed-phase charge with relatively low feed vaporization, in that it avoids the necessity for employing extremely large plugs to increase the vapor velocity. This will be apparent from inspection of the following data comparing the results obtained first (Table I) in the use of a conventional single feed nozzle and then (Table II) in the use of a multiple nozzle in accordance with the present invention, two examples being given in each case.

Table 1 Ex. 1 Ex. 2

Steam to heater inlet, lbs/hr 1,500 l, 500 Total steam to nozzle:

wt. percent h 2.0 2.0 lbs/hr 4, 270 7,270

Steam assumed to be in partial pressure equilibrium at nozzle, lbs.[hr 1, 500 1, 270 Nozzle loading at liquid loading factor of 0.033 c.f.s./m.

of diameter, inches 46 38 Plug required to give vapor velocity of 38.5 it./sec. at

above conditions, percent 70 50 Table II [33% of charge to 16" I. D. inner nozzle with a 50% plug. 67% of charge to 32" I. D. outer nozzle with a 50% plug] Ex. 1 Ex. 2

Inner Outer Inner Outer Steam to heater inlet, lb./hr 500 1 000 500 1,000 Total steam to nozzle, lb./hr 500 6, 720 500 6, 770 Steam assumed to be in partial pressure equilibrium at nozzle, lh./hr. 500 1, 000 500 6, 770 Liquid loading 0.115. inch of diameter 0. 0308 0.0308 0. 0.508 0. 0250 Vapor velocity, it./sec 40 35 40 40 From the foregoing data it may be seen that the desired high vapor velocities in the range of about 35-45 ft./'sec. are readily attained with a multiple nozzle of considerably smaller overall diameter than would be required with a single nozzle, while at the same time providing substantially increased operating flexibility. The nozzle design of the present invention permits desirable control over the oil distribution through the inner and outer nozzles by connecting separate heater passes to each nozzle. Furthermore, it has the advantage of permitting the steam addition to be varied between the inner and outer nozzles in order to obtain optimum vapor-liquid relationships.

Although but one embodiment of the invention has been illustrated and described, it is obvious that various modifications are possible within the spirit of the invention. For example, as previously stated, the nozzles 22 and 23 may discharge at the same level within chamber 13, or at diiferent levels. When nozzle 22 is at a lower level, it must not be so far below as to cause its liquid discharge to spray too far down on the falling curtain of solids; and when it is at a higher level it must not be so far above the outer nozzle as to cause the two liquid sprays to merge before reaching the curtain. Also, and particularly when the level of discharge for nozzle 22 is at or below the level of discharge for nozzle 23, an inclined deflecting ring may be secured about the lower outer perimeter of nozzle 22 so as to outwardly deflect the vaporous material discharging from annular path 27. Such deflection will cause the gaseous material to flow more nearly parallel to the discharging liquid streams at the level of discharge. It is desired, therefore, that only such limitations shall be imposed upon the invention as are indicated by the appended claims.

What is claimed is:

1. In a hydrocarbon conversion process in which a mixed-phase stream of hydrocarbons is introduced into a conversion zone from within an annular curtain of granular contact material falling freely onto the surface of a compact moving bed of such material maintained within said zone, the method for contacting the falling solids with the liquid component of said mixed-phase stream which comprises the steps of: passing a portion of said mixed-phase stream vertically downward as a confined stream coincident with the axis of said annular curtain; passing the remaining portion of said mixedphase stream downward as an annular confined stream surrounding said axial stream; imparting a rotating motion to each of said streams along a portion of its respective confined path located at least one path diameter above the lower end thereof, said rotating motion being sufficient to eifect a separation of each mixed-phase stream into an outer portion comprising a rapidly-rotating, circumferentially-completc liquid layer and an inner portion comprising substantially liquid-free vaporous hydrocarbons; passing the separated hydrocarbon streams, without substantial flow restriction, along the remaining portions of their confined paths; and discharging each of said rotating liquid layers concentrically within said curtain, whereby each annular rotating stream of discharged liquid is directed downwardly and outwardly from the lower outer perimeter of its respective confined path toward said annular curtain as separate, superimposed, expanding, hol low streams of dispersed liquid droplets which are substantially entirely intercepted by said curtain of falling solids before the latter reach the surface of said bed.

2. The method as in claim 1 in which said annular confined path discharges at a level higher than the discharge level of said axial confined path.

3. The method as in claim 1 wherein the rotation of said mixed-phase streams is effected by flowing the same helically along the intermediate portion of their respective confined paths.

4. The method as in claim 3 wherein the mixed-phase axial and annular confined streams are subdivided into a aesacsae 9 plurality of helical streams along said intermediate portions.

5. In a hydrocarbon conversion system wherein a mixed-phase charge of hydrocarbons are converted within a reactor in the presence of a compact moving bed of granular contact material, and wherein said granular material is introduced into said reactor as an annular curtain of solids falling freely onto the surface of said bed, the combination therewith of means for introducing said mixed-phase charge into said reactor from within said curtain and for effecting contact of the liquid component thereof with said curtain of solids comprising; a vertical cylinder positioned axially within said falling curtain; a cylindrical plug member located axially within said cylinder at a distance of at least one diameter above its lower end and forming therewith an annular space; a plurality of inclined vanes uniformly distributed around said annular space and serving to support said plug member rigidly within said cylinder; a second cylinder concentrically surrounding said first cylinder so to form therewith a second annular space; a second plurality of inclined vanes uniformly distributed about said second annular space; and separate means communicating with the upper end of the first cylinder and the upper end of said second annular space for distributing thereto a controlled proportion of said mixed-phase charge.

6. Apparatus as defined in claim 5 in which said first cylinder extends downwardly below the lower end of said second cylinder so as to provide different levels of discharge for the separate streams of hydrocarbons passing through said first cylinder and through said second annular space. I

7. Apparatus as defined in claim 5 including deflector means around the lower end portion of said first cylinder adapted to deflect outwardly the vaporous hydrocarbons flowing downwardly around the outer periphery of said first cylinder.

8. Apparatus as in claim 5' including means surrounding said second cylinder and defining therewith a narrow annular insulating space; means surrounding said insulating space and defining with said last-mentioned means a confined annular passageway adapted to convey said granular material as a compact moving stream downwardly into said reactor; and means for discharging said granular material within said reactor as a circumferentiallycomplete annular curtain of freely-falling solids concentrically surrounding said means for introducing the mixedphase charge of hydrocarbons.

References Cited in the file of this patent UNITED STATES PATENTS 2,296,426 Coutant Sept. 22, 1942 2,538,195 Henkel Jan. 16, 1951 2,636,805 Lassiat et a1. Apr. 28, 1953 2,663,677 Savage et al. Dec. 22, 1953 2,683,109 Norris July 6, 1954 2,786,801 McKinley et al. Mar. 26, 1957

Claims (1)

1. IN A HYDCARNON CONVERSION PROCESS IN WHICH A MIXED-PHASE STEEAM OF HYDROCARNON IS INTRODUCED INTO A CONVERSION ZONE FROM WITHIN AN ANNULAR CURTAIN OF GRANULAR CONTACT MATERIAL FALLING FREELY ONTO THE SURFACE OF A COMPACT MOVING BED OF SUCH MATERIAL MAINTAINED WITHIN SAID ZONE, THE METHOD FOR CONTACTING THE FALLING SOLIDS WITH THE LIQUID COMPONENT OF SAID MIXED-PHASE STREAM WHICH COMPRISES THE STEPS OF: PASSING A PORTION OF SAID MIXED-PHASE STREAM VERTICALLY DOWNWARD AS A CONFINED STREAM COINCIDENT WITH THE AXIS OF SAID ANNULAR CURTAIN; PASSING THE REMAINING PORTION OF SAID MIXEDPHASE STREAM DOWNWARD AS AN ANNULAR CONFINED STREAM SURROUNDING SAID AXIAL STREAM; IMPARTING A ROTATING MOTION TO EACH OF SAID STREAMS ALONG A PORTION OF ITS RESPECTIVE CONFINED PATH LOCATED AT LEAST ONE PATH DIAMETER ABOVE THE LOWER END THEREOF, SAID ROTATING MOTION BEING SUFFI-

Images