US3120485A - Method and apparatus for contacting liquid with granular contact material - Google Patents

Description

Feb. 4, 1964 w. J. cRoss, JR 3,120,485

METHOD AND APPARATUS FOR CONTACTING LIQUID WITH GRANULAR CONTACT MATERIAL Filed Jan. 18, 1961 2 Sheets-Sheet 1 IN V EN TOR.

ATTORNEY W. J. CROSS, JR

Feb. 4, 1964 D I U Q I L GA NI R TE T m 0 m RT 0 8 m P R G D mm m w m E M 2 Sheets-Sheet 2 Filed Jan. 18, 1961 aw... n

INVENTOR. Phi/Z20 cf Cram; :5? BY ATTORNEY United States Patent 3 120,485 METHOD AND APPARATUS FOR CONTACTING LIQUID WITH GRANULAR CONTACT MATERIAL Willis J. Cross, Jr., Media, Pa., assignor to Air Products and Chemicals, Inc, a corporation of Delaware Filed Jan. 18, 1961, Ser. No. 83,427 11 Claims. (Cl. 208-167) 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 gnanular, 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 U.S. Patent 2,906,705 of Willis J. Cross, Jr., for Method for Contacting Liquid With Granular Contact Material, and U.S. Patent 2,886,- 520 of Julius J. Cicalese for Method and Apparatus for Contacting Liquid With Granular Contact Material.

The use of higher boiling fractions of crude oil, such as vacuum gas oils, tar separator bottoms, reduced crudes, 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 degrees F. or higher. Hence, even if these fractions are vaporizable at temperatures of 900 degrees F. to 1000 degrees 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 tendto 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 off 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 ment of the contact material, even to the point of stopping the flow of contact material out of the reactor. The prior art has diligently and actively sought methods which avoid these 'difiiculties. A commercially successful method is disclosed in U.S. Patent No. 2,520,146, to Rueben T. Savage. It involves the projection of liquid hydrocarbons 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.

" design which will give improved distribution of liquid In the aforementioned Cross patent there is disclosed a liquid feed nozzle comprising a cylindrical member provided with internal sloping v anes 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 circumferentiallycomplete 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 sufiicient 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 Ian-d 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 Cross patent, descends concentrically around and below the liquid feed nozzle to the sur iace 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.

The Cicalese patent is directed to an improved nozzle 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. The patent provides 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 Cross patent, 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 manner so that the desired flow characteristics are achieved in each flow path.

It is highly desirable to provide a liquid hydrocarbon spray emitting from the nozzles of the above-described apparatus, as nearly horizontal as possible, without increasing the horizontal impact force of the liquid spray droplets. This permits the liquid droplets to meet and uniformly coat the granules of contact material at a level closer to the top of their free fall, i.e., the top of the annular curtain, and permits a reduction in the distance of free fall, thereby minimizing loss of contact material caused by attrition of particle to particle contact. A spray closer to the horizontal also permits the more uniform distribution of liquid over the contact material surface because the liquid droplets are directed to larger areas of undersurface of the falling particles, which areas are not exposed to a downwardly directed spray.

The provision of rotation to the liquid of the mixedphase by the use of vanes and the like provides outstanding results in converting the mixed-phase into a rotating liquid helice with a vapor core and thereby spraying the liquid when it emits from the nozzle. If the rotational velocity of the liquid is too low, however, large liquid droplets tend to form on the central portions of the vanes and the lips of the nozzle through merging of the smaller droplets and eventually the droplets become sufficiently large to drip off onto the bed of contact material below. This inadvertent dripping of liquid onto the bed of contact material represents a loss of efiiciency and an increased loss of liquid hydrocarbon, e.g., through coke formation, carried out with the contact material withdrawn for regeneration. In any event, such liquid drippings do not uniformly distribute over the free-falling particles of contact material and thus are not completely converted. To avoid such possibility of dripping because of too low velocity, it has heretofore been necessary to adhere to fairly fixed vaporliquid ratios and throughput rates of the mixed-phase feed or to adjust the vapor content by addition of steam to the feed.

A principal object of the present invention, therefore, is to provide an improved nozzle design which will provide greater flexibility of operation with reduced requirement for addition of steam to control velocity, while obtaining improved distribution of liquid over the falling curtain of contact material. Moreover, practice of the invention will minimize or eliminate the possibility of liquid hydrocarbon dripping directly onto the bed of contact material below the nozzle as a result of reduction in charge rate of the mixed-phase feed, thus providing a more efficient conversion of the mixed-phase hydrocarbons.

The present invention provides an improved method and apparatus of the type described in the Cross and Cicalese patents, wherein, the rotation of the mixed-phase hydrocarbon stream, or streams, and a more efficient separation of said stream into a liquid annulus and a vapor core, are more readily obtained, relatively higher, more horizontal liquid spray is obtained, and the occurrence of dripping at the vane or nozzle outlet is considerably reduced or eliminated.

The present invention more particularly is an improvement on the methods and apparatus of the Cross patent and the Cicalese patent and comprises feeding the mixedphase hydrocarbons tangentially into the nozzle downspout in order to provide an initial rotation and thereby cause separation of some of the liquid hydrocarbons of the mixed-phase prior to reaching the vanes which provide the final rotational motion to the stream. The initial rotation provided by tangential feeding of the mixedphase hydrocarbons reduces the steam requirement otherwise needed to maintain the velocity effective in directing the liquid outwardly toward the curtain of falling catalyst without dripping of liquid onto the catalyst bed below. In addition, the initial rotation effects better distribution of the liquid phase since such rotation tends to avoid uneven concentration of liquid in the feed line and the formation of droplets when the mixed-phase stream reaches the vanes, and thus permits better separation of the liquid phase as an annulus from the vapor phase as the core of the stream.

The methods and apparatuses of the above-mentioned Cross and Cicalese patents are also improved by this invention by deflecting the vapor stream emitting from the nozzle, for example, by the use of a bell-shaped deflector mounted just below the nozzle outlet, and thereby directing the vapor phase in a substantially horizontal direction for a short distance, whereupon the liquid droplets of the spray exiting from the nozzle are carried for a short distance by the horizontally deflected vapor phase. By thus assisting the liquid spray in a horizontal direction, lower rotational velocities may be utilized effectively without dripping despite temporary velocity reduction. No substantial additional momentum is provided to the spray which would normally 4.- cause disruption of the falling curtain of contact material. The defiection of the vapor stream as it exits from the nozzle also tends to prevent the dripping of liquid from the nozzle lips.

For a fuller understanding of the invention, reference is made to the following detailed description of a specific embodiment described in connection with the accompanying drawings in which:

FIGURE 1 is an elevation view of the upper regions of a typical reactor, the bottom half of which is cut away, portions of the reactor being illustrated in partial section to show the arrangement of the improved nozzle;

FIGURE 2 is a plan view of the nozzle taken along line 22 of FIGURE 1; and

FIGURE 3 is an enlarged fragmentary view in partial section of the central portion of FIGURE 1, showing the details of the lower portions of the said nozzle.

In the drawings the invention is disclosed in connec tion 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 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 acid-activated 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 upper mouth of each downcomer 17 is provided with a grating cage 17a, which prevents oversized particles from entering and possibly clogging the downcomer. 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 reac tion 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 (not shown).

'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. 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. 1 and the details of the nozzle are more clearly illustrated in the enlarged view of FIG. 3. While the liquid-vapor 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 spaces or flow paths.

Specifically, the nozzle comprises three elongated cylindrical members 22, 23 and 24, numbered in the order of increasing diameter. The innermost cylinder 22 provides a flow path 26 for a mixed-phase stream of hydrocarbons. The annular passageway 27 formed between cylinder 22 and its next outward adjacent cylinder 23 is available for insulation or for the passage of steam or another stream of mixed-phase hydrocarbon, as desired. The annular space 28 between cylinders 23 and 24 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 24 extends through an opening in the tube-sheet 14 and communicates with the catalyst bed 16. The top of cylinder 24 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 ag glomerated masses of catalyst which might eventually clog the catalyst discharge gap at the lower end of annular passageway 28.

The cylinder 22 is closed at its upper end and hydrocarbon feed line 32 is tangentially connected to and tangentially communicates with cylinder 22 adjacent its upper end as best shown in FIGS. 1 and 2. The mixed-phase hydrocarbon is thus fed tangentially into cylinder 22 to provide an initial rotation which assists the separation of liquid hydrocarbon into an annulus and vaporous hydrocarbon into a core within the liquid annulus. -It is to be understood, however, that provision maybe 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, e.g., as shown in the Cicalese patent.

Annular space '27 can serve to insulate the hydrocarbon stream within the flow path 26 from the high temperature catalyst stream flowing downwardly through annular space 28. Optionally steam or other suitable gaseous material may be introduced into annular space 27 so as to flow downwardly through said annular space and be discharged into chamber 13 about the lower end portion of cylinder 22, thereby carrying ofi some of the heat from the wall of cylinder 22. The lower end of cylinder 24 is at a level substantially higher than the lower end of cylinder 23. A relatively short cylinder 33 concentrically surrounds and is spaced from the lower end of cylinders 23 and 24 and is rigidly supported by and spaced from cylinder 23 by suitable radial fins or struts, not shown. Cylinder 33 is spaced outwardly from cylinders 23 and 24 so as to form an upper annular gap 34 and a lower annular gap 35.

Catalyst flowing downwardly through annular passage 28 is deflected outwardly by the mass of catalyst retained Within the cylinder 33. In flowing outwardly beneath the lower end of cylinder 24', the catalyst forms an annular exposed surface of solids 36 through which gaseous material accompanying the catalyst along annular path 28 may be disengaged. The disengaged gas is discharged into chamber 13 through the annular passage or gap 34.

The lower ends of cylinders 23 and 33 also are provided with annular re-enforcing rings 37 and 38 respectively, to the underside of which are attached inner and outer flat annulus rings 39 and 40 respectively. The inner periphery of annulus ring 39 is slightly spaced from the outer wall surface of cylinder 22 so as to form therewith a narrow gap through which gas flowing downwardly through annular passage 27 may escape into chamber 13. The opposed vertical edges of annulus rings 39 and 40 are horizontally spaced to provide the catalyst flow control gap 35. Catalyst flowing downwardly be tween cylinders 23 and 24 discharges through gap 35 to form an annular free-falling curtain of solids.

The feed nozzle formed by cylinder 22 is similar-to that disclosed in the aforementioned Cross, Jr., patent. The nozzle comprises a central cylindrical plug member 41 surrounded by a plurality of inclined vanes 42. Three vanes, at an angular spacing of 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 suflicient 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. In the nozzle passage 26, 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.

The cylindrical plug member 41 extends substantially concentrically below cylinder 22 and has attached to its lower end a bell-shaped deflector 43 which deflects the vaporous hydrocarbons outwardly after the exit from the cylinder 22 to carry the liquid droplets horizontally for a short distance. The diameter of the largest circumference of bell-shaped deflector 43 is preferably at least as great as the diameter of cylinder 22 although said diameter can be greater or smaller, depending on the length of horizontal deflection desired, the larger diameters providing a longer horizontal travel.

Although but one embodiment of this invention has been illustrated and described in detail, it is obvious that various modifications are possible within the spirit of the invention. For example, the multiple nozzle arrangement taught by the above-mentioned Cicalese patent can be employed with tangential feeding to one or any number of the nozzles. Similarly, the lower nozzle construction of either of the above-mentioned Cicalese or Cross patents can be employed. The deflector below the nozzle can also be applied to one or more of the nozzles of the Cicalese patent as well as being applied to the nozzle of the Cross patent. If desired to provide cooling water or process steam to the liquid feed nozzle, water in liquid state may be introduced through cylinder 22 while the mixed-phase hydrocarbon feed is introduced tangentially into and passed through a concentric annular space surrounding said cylinder and provided in said space with a vaned propeller member as already described. 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 wherein liquid and vaporous hydrocarbons are converted in the presence of a compact moving bed of granular contact material which gravitates through a conversion zone and is continuously replenished by particles of said material introduced downwardly into said zone as an annular curtain of solids falling freely onto the surface of said bed, the method for contacting said particles with said liquid hydrocarbons which comprises the steps of: feeding a mixed-phase stream of fluid comprising said liquid hydrocarbons tangentially into a downward, straight, confined path substantially concentric with said curtain to cause said mixed-phase stream to flow helically downward, which path, except for an intermediate portion spaced at least one path diameter from the lower end thereof, is of substantial-1y uniform flow area throughout its length; deflecting said mixed-phase stream helically along said intermediate portion, the helical flow of said mixed-phase stream causing the liquid component of said stream to rotate about the axis of said path, the centrifugal force of said rotation causing said liquid to flow along said confined path as a rotating circumferentially complete annular stream having a hollow substantially liquid-free central portion forming an unobstructed flow path for the vaporous portion of said mixed-phase stream; discharging said mixed-phase stream of hydrocarbons axially downward at an upper central location within said falling curtain of granular material; and deflecting said hollow, substantially liquid-free central portion of said vaporous portion outwardly from the approximate axis of said central portion after discharge; whereby said discharged annular rotating stream of liquid is directed outwardly from the lower perimeter of said confined .path toward said annular curtain as an expanding hollow stream of dispersed liquid droplets which are substantially entirely intercepted by the falling granular material before the latter reaches the surface of said bed.

2. The method as defined in claim 1, wherein said mixed-phase stream is deflected helically along said intermediate portion by flowing the latter along said intermediate portion of the vertical confined path as a plurality of separate parallel streams of equal flow area, said parallel streams being directed along substantially helical paths disposed about the longitudinal axis of said confined path.

3. A method as defined in claim 1 in which the velocity of discharge from said vertical confined path is the maximum consistent with the formation of a discharging liquid spray of fine droplet size and uniform peripheral distribution without appreciable formation of mist.

4. In a hydrocarbon conversion process wherein liquid and vaporous hydrocarbons are converted in the presence of a compact moving bed of granular contact material which gravitates through a conversion zone and is continuously replenished by particles of said material introduced downwardly into said zone as an annular curtain of solids falling freely onto the surface of said bed, the method for contacting said particles with said liquid hy drocarbons which comprises the steps of: feeding a mixedphase stream of fluid comprising said liquid hydrocarbons tangentially into a downward, straight, confined path substantially concentric with said curtain to cause said mixedphase stream to flow helically downward, which pat-h, except for an intermediate portion spaced at least one path diameter from the lower end thereof, is of substantially uniform flow area throughout its length; deflecting said mixed-phase stream helically along said intermediate portion, the helical flow of said mixed-phase stream causing the liquid component of said stream to rotate about the axis of said path, the centrifugal force of said rotation causing said liquid to flow along said confined path as a rotating circumferentially-complete annular stream having a hollow substantially liquid-free central portion forming an unobstructed flow path for the vaporous portion of said mixed-phase stream; and discharging said mixedphase stream of hydrocarbons axially downward at an upper central location within said falling curtain of granular material, whereby said discharged annular rotating stream of liquid is directed outwardly from .the lower perimeter of said confined path toward said annular curtain as an expanding hollow stream of dispersed liquid droplets which are substantially entirely intercepted by the falling granular material before the latter reaches the surface of said bed.

5. In a hydrocarbon conversion process wherein liquid and vaporous hydrocarbons are converted in the presence of a compact moving bed of granular contact material which gravitates through a conversion zone and is continuously replenished by particles of said material introduced downwardly into said zone as an annular curtain of solids falling freely onto the surface of said bed, the method for contacting said particles with said liquid hydrocarbons which comprises the steps of: passing a mixedphase stream of fluid comprising said liquid hydrocarbons axially and downwardly along a straight, confined path within said conversion zone, which path, except for an intermediate portion spaced at least one path diameter from the lower end thereof, is of substantially uniform flow area throughout its length; deflecting said mixedphase stream helically along said intermediate portion, the helical flow of said mixed-phase stream causing the liquid component of said stream to rotate about the axis of said path, the centrifugal force of said rotation causing said liquid to flow along said confined path as a rotating circumferentially-complete annular stream having a hollow substantially liquid-free central portion forming an unobstructed flow path for the vaporous portion of said mixed-phase stream; discharging said mixed-phase stream of hydrocarbons axially downward at an upper central location within said falling curtain of granular material; and deflecting said hollow, substantially liquid-free central portion of said vaporous portion outwardly from the approximate axis of said central portion after discharge; whereby said discharged annular rotating stream of liquid is directed outwardly from the lower perimeter of said confined path toward said annular curtain as an expanding hollow stream of dispersed liquid droplets which are substantially entirely intercepted by the falling granular material before the latter reaches the surface of said bed.

6. In apparatus for the conversion of mixed-phase hydrocarbons in the presence of a compact moving bed of granular contact material contained within a reactor vessel including means for introducing said contact material downwardly into said vessel as a free-falling annular curtain of particles depositing upon the surface of said bed, the combination therewith of a mixed-phase fluid supply conduit having its discharge end extending axially downward into the space within said falling curtain, said lower end portion comprising a straight, non-tapered cylindrical member; a mixed-phase feed conduit tangentially communicating with the upper end of said supply conduit to provide a helical path to said mixed-phase fluid as it enters said supply conduit; a plurality of inclined vanes uniformly distributed about the axis of said cylindrical member at a common intermediate level therein and at a distance of at least one diameter above the lower end thereof, said vanes being inclined to the axis of said cylindrical member, and a bell-shaped deflector mounted substantially concentrically below said discharge end of said supply conduit to deflect the discharging fluid outwardly from the axis of said lower end portion; thereby providing a plurality of helical flow paths at said intermediate level through which the liquid component of a mixed-phase stream is rotated sufiiciently to cause said liquid component to flow through the remaining portion of said cylindrical member as a rotating circumferentially-complete annular stream of liquid and be discharged therefrom as an expanding hollow stream of dispersed liquid droplets.

7. In apparatus for the conversion of mixed-phase hydrocarbons in the presence of a compact moving bed of granular contact material contained within a reactor vessel including means for introducing said contact material downwardly into said vessel as a free-falling annular curtain of particles depositing upon the surface of said bed, the combination therewith of a mixed-phase fluid supply conduit having its discharge end extending axially downward into the space within said falling curtain, said lower end portion comprising a straight, non-tapered cylindrical member; a mixed-phase feed conduit tangentially communicating with the upper end of said supply conduit to provide a helical path to said mixed-phase fluid as it enters said supply conduit; a plurality of inclined vanes uniformly distributed about the axis of said cylindrical member at a common intermediate level therein and at a distance of at least one diameter above the lower end thereof, said vanes being inclined to the axis of said cylindrical member, thereby providing a plurality of helical flow paths at said intermediate level through which the liquid component of a mixed-phase stream is rotated sufiiciently to cause said liquid component to flow through the remaining portion of said cylindrical member as a rotating circumferentially-complete annular stream of liquid and be discharged therefrom as an expanding hollow stream of dispersed liquid droplets.

8. In apparatus for the conversion of mixed-phase hydrocarbons in the presence of a compact moving bed of granular contact material contained within a reactor vessel including means for introducing said contact material downwardly into said vessel as a free-falling annular curtain of particles depositing upon the surface of said bed, the combination therewith of a mixed-phase fluid supply conduit having its discharge end extending axially downward into the space within said falling curtain, said lower end portion comprising a straight, non-tapered cylindrical member; a plurality of inclined vanes uniformly distributed about the axis of said cylindrical member at a common intermediate level therein and at a distance of at least one diameter above the lower end thereof, said vanes being inclined to the axis of said cylindrical member, and a bell-shaped deflector mounted substantially concentrically below said discharge end of said supply conduit to deflect the discharging fluid outwardly from the axis of said lower end portion; thereby providing a plurality of helical flow paths at said intermediate level through which the liquid component of a mixed-phase stream is rotated sufliciently to cause said liquid component to flow through the remaining portion of said cylindrical member as a rotating circumferentially-complete annular stream of liquid and be discharged therefrom as an expanding hollow stream of dispersed liquid droplets.

9. 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 eifecting 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; separate means tangentially communicating with the upper end of the first cylinder and the upper end of said second annular space for tangentially distributing thereto liquid-containing feeds, at least one of said feeds being mixed-phase hydrocarbon charge, and a bell-shaped deflector mounted substantially concentrically below the lower end of said first cylinder to deflect the fluid discharged therefrom outwardly from the axis of said cylinder.

10. Apparatus as defined in claim 9 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 liquid-containing feeds passing through said first cylinder and through said second annular space.

11. Apparatus as in claim 9 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 passage-way 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 circumferentially-complete annular curtain of freely-falling solids concentrically surrounding said means for introducing the mixed-phase charge of hydrocarbons.

References Cited in the file of this patent UNITED STATES PATENTS 2,886,520 Cicalese May 12, 1959 2,903,420 Wilki Sept. 8, 1959 2,906,705 Cross Sept. 29, 1959

Claims (1)

1. IN A HYDROCARBON CONVERSION PROCESS WHEREIN LIQUID AND VAPOROUS HYDROCARBONS ARE CONVERTED IN THE PRESENCE OF A COMPACT MOVING BED OF GRANULAR CONTACT MATERIAL WHICH GRAVITATES THROUGH A CONVRSION ZONE AND IS CONTINUOUSLY REPLENISHED BY PARTICLES OF SAID MATERIAL INTRODUCED DOWNWARDLY INTO SAID ZONE AS AN ANNULAR CURTAIN OF SOLIDS FALLING FREELY ONTO THE SURFACE OF SAID BED, THE METHOD OF CONTACTING SAID PARTICLES WITH SAID LIQUID HYDROCARBON WHICH COMPRISES THE STEPS OF: FEEDING A MIXED-PHASE STREAM OF FLUID COMPRISING SAID LIQUID HYDROCARBON TANGENTIALLY CONCENTRIC WITH SAID CURTAIN TO CAUSE SAID MIXED-PHASE STREAM TO FLOW HELICALLY DOWNWARD, WHICH PATH, EXCEPT FOR AN INTERMEDIATE PORTION SPACED AT LEAST ONE PATH DIAMETER FROM THE LOWER END THEREOF, IS OF SUBSTANTIALLY UNIFORM FLOW AREA THROUGHOUT ITS LENGTH; DEFLECTING SAID MIXED-PHASE STREAM HELICALLY ALONG SAID INTERMEDIATE PORTION, THE HELICAL FLOW OF SAID MIXED-PHASE STREAM CAUSING THE LIQUID COMPONENT OF SAID STREAM TO ROTATE ABOUT THE AXIS OF SAID PATH, THE CENTRIFUGAL FORCE OF SAID ROTATION CAUSING SAID LIQUID TO FLOW ALONG SAID CONFINED PATH AS A ROTATING CIRCUMFERENTIALLY COMPLETE ANNULAR STREAM HAVING A HOLLOW SUBSTANTIALLY LIQUID-FREE CENTRAL PORTION FORMING AN UNOBSTRUCTED FLOW PATH FOR THE VAPOROUS PORTION OF SAID MIXED-PHASE STREAM; DISCHARGING SAID MIXED-PHASE STREAM OF HYDROCARBONS AXIALLY DOWNWARD AT AN UPPER CENTRAL LOCATION WITHIN SAID FALLING CURTAIN OF G RANULAR MATERIAL; AND DEFLECTING SAID HOLLOW, SUBSTANTIALLY LIQUID-FREE CENTRAL PORTION OF SAID VAPOROUS PORTION OUTWARDLY FROM THE APPROXIMATE AXIS OF SAID CENTRAL PORTION AFTER DISCHARGE; WHEREBY SAID DISCHARGED ANNULAR ROTATING STREAM OF LIQUID IS DIRECTED OUTWARDLY FROM THE LOWER PERIMETER OF SAID CONFINED PATH TOWARD SAID ANNULAR CURTAIN AS AN EXPANDING HOLLOW STREAM OF DISPERSED LIQUID DROPLETS WHICH ARE SUBSTANTIALLY ENTIRELY INTERCEPTED BY THE FALLING GRANULAR MATERIAL BEFORE THE LATTER REACHES THE SURFACE OF SAID BED.

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