US2678874A

US2678874A - Gas distributing and collecting channels for reaction vessels

Info

Publication number: US2678874A
Application number: US124058A
Authority: US
Inventors: Charles S Parker; Robert M Shirk
Original assignee: Houdry Process Corp
Current assignee: Houdry Process Corp
Priority date: 1949-10-28
Filing date: 1949-10-28
Publication date: 1954-05-18
Anticipated expiration: 1971-05-18

Description

May 18, 1954 c. s. PAR l-:iRv ETAL 2,678,874

3 rwentors Gttorneg Patented May 18, 1954 GAS DISTRIBUTING AND COLLECTING CHANNELS FOR REACTION VESSELS Charles S. Parker, Philadelphia, Pa., and Robert M. Shirk, Wilmington, Del., assgnors to Houdry Process Corporation, Philadelphia, Pa., a corporation of Delaware Application October 28, 1949, Serial No. 124,058

7 Claims. 1

This invention relates to gas distributing and collecting channels for reaction vessels, and particularly to the type of channel commonly employed in reactors for converting hydrocarbons in the presence of a moving bed of granular solid particles, and in kilns for regenerating or reactivating by combustion the granular solid particles after they have received a deposit of carbonaceous material as a result of their previous contact with hydrocarbon vapors in the conversion zone. The invention is more particularly directed to systems wherein the granular solid particles are passed downwardly in the form of a moving bed through a vessel in which a plurality of inverted channel members are horizontally arranged sideby-side and spaced to provide a grid through which the catalyst passes in traveling downwardly through the vessel. The channel members may be conveniently grouped in a series of vertically spaced grid-forming layers, so that the channels in certain layers may be used to introduce a gaseous reactant to the moving bed of solid particles and the channels in other layers may be used to convey out of the vessel the gaseous reaction products which have become separated from the particles in the zones beneath the channels. A typical system embodying structure to which the present invention is especially applicable has been described by R. H. Newton, G. S. Dunham, and T. P. Simpson in a paper entitled The T. C. C. Catalytic Cracking Process for Motor Gasoline Production, reported in Transactions of American institute of Chemical Engineers, volume 4l, Number 2, April 25, 1945.

For the purpose of illustrating the invention the channels will hereinafter be referred to and described in connection with a kiln for regenerating the catalyst.

Heretofore, it has been a common practice to support the ends of the channel members on short complementary-shaped channel sections attached to the chamber wall and to the central beam, and adapted for nested engagement with the channel ends, provision being made for limited longitudinal movement of the channels to allow for expansion requirements in view of the high temperatures employed in the kiln. Several disadvantages are inherent in this type of construction, the principal disadvantage being the lack of uniform gas seal between the ends of the f channels and the side walls of the beam header or of the vessel, depending upon whether internal or external manifolding is employed, as a result of longitudinal shifting of the channels on the supports. Failure to maintain an adequate seal permits by-passing of the oxygen-containing gas through the space between the end of the channel and the adjacent Wall surface directly into the bed above the channel, producing an undesirable concentration of oxygen at such point, and also permits ley-passing streams of gaseous products of combustion to carry solid particles into the flue outlets. Various expediente have been employed to maintain the channels in their proper position but these expedients usually ineluded fastening means, such as straps or bolts, which, while they overcame the problem of shifting, introduced a different problem in that the work of assembling and dismantling the units required additional expenditures of time and labor.

In accordance with the present invention the channels are supported at the ends which are in communication with the gas inlet or gas outlet conduits by members having contacting support surfaces inclined to the vertical, so arranged that the end-plate of the channel is constantly urged in the direction of its opposite sealing surface. The opposite ends of the channels are supported on suitable members which are xed with respect to the chamber wall, sufficient clearance being left between the end of the channel and the supporting means to permit longitudinal movement of the channel, such as may occur when the channel is expanding as a result of increased temperature or when the channel is being installed or removed.

The invention is adapted to be used in either a system in which the channels are continuous for the full width of the kiln and are externally manifolded, or a system in which a beam manifold is provided diametrically across the kiln with lateral conduits on either side communicating with the channel. In either case, the same construction may be provided for the` end of the channelv communicating with the manifold.

For a more complete understanding of the invention reference may be had to the accompanying drawing forming a part of this application, in which:

Fig. l is an elevation View of a typical kiln l embodying the channel construction of the present invention, in which a portion of the kiln has been broken away to show in section the details of the channel structure.

2 is a fragmentary enlarged view of a single channel with a portion broken away to show the details of construction at the ends.

Fig. 3 is a section View taken along the line 3-3 of Fig. 2; and

Fig. 4 is a view showing a preferred channel arrangement for use in a circular kiln, in which the gas manifolds extend diametrically across the kiln.

Referring to the drawing, Fig. 1 shows a typical regenerator or kiln, .such as. may be used in connection with the-catalytic crackingof hydrocarbons, generally indicated by the numeral li.

Granular catalytic material withdrawn from a.

reaction zone, not shown, and bearing a carbonaceous deposit thereon, is introduced to# the kiln through an inlet i2 located. centrally iniztheupper end. Within the kiln H, .the catalyst passes downwardly as a compact ymoving, bed

through a series of regeneration stages, several: of which are shown through the opening formed.

by breaking away a portion of the Vessel. After a residence time within thekiln suill'cient to` remove by combustion the carbonaceous deposit, the regenerated catalyst ris withdrawn from the bottoni of. the kiln through` outlet i3, after which itmay be reintroduced tothe aforementioned reaction: zone. inthe specific embodiment il lustrated in Figi the gas distributingand collecting channelsr ofthe present invention are shown' in-'connection witlrakiln ci rectangular cross-section, butit is to ybe understood that the`invention-is not so limited, and that thev channels'and channel supporting devices hereinafter-'described indetail may be used in kilns of-'circularvor other desired cross-section.

In passing downwardly through the kiln Il, themovingfbed'of catalyst passes successively through a series of Igridsfeach comprising a plural-ity" of invertedA channels arranged side-byside in a horizontall plane/andlaterally spaced to Iprovide-narrow spacesor slotsthrough which the catalystmay pass downwardly. The series of horizontal grids `formed by the channel mem-- bers are-verticallyspaced within the kiln so lthat the-catalyst-bed which has been separated into individual*l streams in passing throughi'a grid may reform-into ay single compact mass before againi'b'eingsubdivided in passing Athrough the next llower-grid.' In'the embodiment of Fig. lA

three such' grids 'areillustrated the middle grid, general-ly indicated by the numeraly lf,'being a gasfdistributing grid, and grids land `ldisposed above and'below the grid it; respectively; being-1: gas collecting grids.

part-:of .the'sgas .passingf upwardly toward the Oxygen containing gas,=. suchi'asxair; isf intrmiucedv into the moving catalyst bed through the channelsiof grid Ill,

vaporccollectingigrid" l5 'countercurrent to the downward-now of 1' catalyst;r and the remaining portion-of the oxygen containing'gas passing`- downwardly toward. the-:lower vapor collecting grid 1 l E :concurrent 1 to the moving Y catalyst bed.l

Engagement .between Ithe catalyst. and nthe oxye genhcontaining gasentering `the. rkiln, andidis-v engagement-,between the catalystand 'the-gas The details of the channel members forming grids vlli; i5 Vand iii Aand the means for supportm ing themY within the kiln are Ashown enlarged ln'FigaiZ and 3. Referring to Fig; 2, a channel ment.

i is shown as comprising three separate sections interengaging to form a continuous inverted V- shaped channel. Each channel consists of two identical elongated end sections it, of sufficient length to extend from a point near the center of the vessel .to a pointadjacent. the side wall, and a short intermediate section: i5 adapted at each end to t under the inner ends oi channel sections i5, in an overlapping nested arrange- The middle sections i9 of a single grid are 'rigidly attached, as by fillet welds along the lower edges thereof to the upper' surface of the conventional .center bea-m 2i) which extends diametrically across Athe kiln at e.. right angle to the channels, .the end of the beam 2d being rigidly connected to .thewalls of the kiln in any suitable manner. A transverse rod 2l extends across each'channcl section i8, projecting through the sidewallsin the lower inner corners thereof, the rod being rigidly held in position by nuts 22 threadedon the outer ends oi the rod, The lower corners of the short channel section .i9 'are undercut so that the ends of section i9 may fit within the channel members i8," just clearing theitransverse rodZi. In assembled position,"

the'inner end of sections It .rest on the outer ends'i'or .section i9, with the transverse rod 2l positioned beneath and adjacent the lower 'edge '2 "formed'loyv undercutting the lower cornersof The Klower inner corners of channel sections Itvr are also undercut slightly to permit'the undersuraces 2d to clear -the centerbeam ''when' the channel sections ES? are moved inwardly beyond the edge ofl the beam, as may occur when thegrids are being assembled yor dismantled.

The louter endof channel section I3 yis'closed byan end-plateihaving a vertically elongated central opening itladapted to receive the inner end 'ofv aconduit 2l extending through the side V, wall ofthel chamber, the conduit 2 'being either an inlet or an outlet dependent upon'whether the associated channel is in -a vgas distributing grid or 1n a gas collecting grid; The outer end of fconduit 2l `may be connected to a horizontal external manifold 28A which communicates with' each? ofI the channel conduitsI 2 at the endoia gridlieferring to Fig. l, a riser 2!) supplies oxygen-'containinglgas to manifold 28 associated withithe conduits of grid l, and a riser 3l serves as a ue for manifolds Ztlassociated with'th'e' conduits of grids :i tand 'l Ei.'

Theinner face of end-plate .7:5 is provided with projections 32'son either side of opening 25 the forward surfaces 33 of which slope downwardly and .inwardly vtoward the surface of the endplategiving the appearance of wedges attached tozzthetinner 'face of the end-plate.

The-'outer face of end-plate 25 isin contact with the vertical sidewall 34 of an insulation retainer 35 of L-shaped cross-section extending horizontally along the side wall of the chamber. The conduits 2l pass through the retainer H. 35 and are embedded in eastable refractory insulation. material 36. Refractory material 31 of any suitable type 'lines the wall of the chamber Il above and below the retainer 35. The short pipe section 2l', which extends inwardly through' the insulated wall of the kiln El passes through vthe ropening 2S in the channel end-plate.

25- #and-.terminates at atponta short distance within the channel. A thrust collar 30 mounted on pipe 21 Within the retainer 35 is rigidly secured along its inner circumference to the pipe section 21 and along its outer circumference to the vertical wall 34, as by welding.

The inner end of pipe section 21 is provided with a pair of diametrically opposite lugs 38 secured to the outer surface of the pipe on a horizontal diameter. The surfaces 39 of the lugs facing outwardly toward the wall of the kiln are inclined to the vertical, the inclined surfaces being complementary to the sloping portions 33 of the wedge-like projections 32. Immediately below the sloping surfaces 33 notches 4| are formed in the end-plate 25 at the sides of the opening 26. The notches 4| are slightly larger than the lugs 38, so that when the channel endplate 25 is slipped over the end of the pipe section 21 the lugs 38 pass through the notches 4l. When the end-plate 25 brought into contact with the vertical wall 34 of the insulation .re-A tainer the end of the channel is permitted to fall in place so that the sloping faces 33 of the wedgelike projections 32 contact the complementary sloping portions 39 of the lugs 38. The wedge connection formed by the projections 32 and the lugs 38 force the end-plate 25 against the vertical wall 34 so that there is an effective seal between the two against the by-passing of gas directly to the space above the channel, and against the admission of catalyst into the flue outlets.

Referring to Fig. 4 of the drawing a modified arrangement of the channels is shown which is especially suitable for use in a kiln of circular cross-section, although such arrangement may also be used in a kiln of rectangular cross-section when it is desired to provide internal headers for introducing combustion supporting gases to the channels and for removing gaseous porducts of combustion therefrom. Fig. 4 shows fragmentary portions of a kiln 42 of circular cross-section in which a central beam 43 supports a header or manifold 44 provided on either side with short pipe sections 45, these pipe sections being similar to but shorter than pipe sections 21. The channel sections 45 of this modification have end-plates 25 at their inner ends which are held in abutting engagement with the outer side surface of the header 44. The outer end of channel section 45 may be supported on a bracket mem ber 41 attached to the wall of the kiln, a sumcient space being provided between the refractory lined wall and the end of 'the channel to allow for expansion of the channel with increasing temperature. An end-plate 48 closes the outer end of channel 46. The end-plate is set inwardly from the channel end, thus providing a recess 49 to receive catalyst that has become trapped between the end of the channel and the refractory lining of the kiln. Downwardly sloping louvers 50 are set horizontally in the recess 45 to permit catalyst to rise upwardly therein when the ex# panding channel is forced against the trapped catalyst.

The channel of the present invention is selflocking and may readily be installed or removed. By reason of the wedging device between the end of the channel and the wall of the kiln, the weight of the bed of catalyst above the channel applies additional force to provide an effective seal at the end of the channel.

While the invention has been particularlydescribed in connection with a kiln for regenerating catalyst, it is to be understood that it is equally well adapted for use in other reaction vessels.`

We claim:

l. In a gas-handling grid for a vertical vessel in which gaseous reactants are contacted with a compact moving bed of granular contact material, said vessel having an internal vertical gridsupporting surface in contact with said moving bed, the combination of a relatively short conduit extending from said grid-supporting surface and having a radially projecting lug member at each side of its free end, said lug member having its rearward face inclined downwardly and inwardly toward said gridsupporting surface, an inverted horizontal trough member having an end closure plate provided with an opening to receive said conduit, said opening being vertically elongated to permit limited vertical movement ofy said tro-ugh member with respect to said conduit and being horizontally extended by cut-out portions at the sides adapted to receive said lug members, and wedge-like members projecting from the inner face of said end closure plate immediatelyf above said cut-out portions, the end surfaces of said wedge-like members being sloped complementary to the inclined surfaces of said lug membersI the arrangement of said lug an d wedge-like members being such that, when said conduit is inserted thro-ugh the lower portion of said elongated opening to a point where said wedge-like members are rearwardly of said lug members and said trough member is released, the sliding engagement of said complementary inclined surfaces will force said end plate tightly against said veitical grid-supporting surface.

2. Apparatus as defined in claim 1 in which said vertical grid-supporting surface is the side wall of said vessel.

3. Apparatus as defined in claim 2 including means supporting the opposite end of said trough member and adapted to permit free longitudinal movement thereof in response to changes in temperature. v

4. Apparatus as defined in claim l in which said vertical grid-supporting surface is a side wall of a gas manifold conduit passing transversely through said bed.

5. Apparatus as dened in claim 4 in which the opposite end of said trough member is freely supported on a support member extending inwardly from the wall of said vessel, and including an end closure plate for said opposite end, and a plurality of vertically-spaced horizontal louver-like members sloping downwardly and outwardly from said opposite end closure plate and terminating adjacent to said vessel wall, the space between said vessel wall and said opposite end closure, and having said support member as its lowermost boundary, being adapted to contain a static compact mass of said contact material which is forced by the longitudinal expansion of said trough member upwardly into the spaces between said louver-like members.

6. In a gas-handling grid for a vertical vessel in which gaseous reactants are contacted with a compact moving bed of granular contact material, and including a gas manifold conduit passing transversely through said bed, an inverted horizontal trough member supported at one end in substantially gas-tight connection with the side of said manifold conduit, a relatively short conduit connecting said trough member to said manifold conduit, support means extending inwardly from the wall of said vessel and freely supporting the opposite end of said trough memben; .anendaclosure folate-.fon f sald'f-opposte Tende and a plurality of vertically-spaced lfiozemtaln;l louVer-like members sloping downwardly and outwardly from said opposite; endiclosure plate and: teicminatngk adjacent -tosaidV vesselwall; i the i spaoefbetween said yessel wall. and saidopposite end closure,y and havingsaid-.snpport 4member asV itsflowei'most boundaiyi being adapted ,-to containaa statica compact` mass of .saidrcontact `ma ter-ialswhich is `forced bythe:longitudinali-expensionv of-'saidtirough-member upwardly; into the spaces'between said louver-l-ike-members.

- 7. In a: gas` handling grid fora -Vertical vessel aclapteduforconducting av reaction ofi`V gaseous reactants-in vtl=1e-presenceof acompact -movingi bedofgranular Contact materiaL' an .in-veitecl.I

trough; member a closedv at' one end by AanV -end plate providedwith` a.1.'eitically-elongated ,een` tra-l Op ening,. a conduit. extending-through. aside I Wallifof.. said vessel and projecting inwardly., through said opening, the inner end-of said con duit .having f lugamembers .extending outwardly alongarhcrizontaldiameter, and having. inclined rearward/surfaces, saidopening insaid endplate being.y and arranged to `permit limited. 'vertical-Y sorted... into .,said...opening to: a/.fpoint Where said-.fx lugs extend. beyond saidv projections. and ithe endl of. :said trough member-fis lowered to bringeinto w engagement said complementary:-y inclined surfaces@ the :foroef oagravity Awill-,cause said .iendfA plate. Y to be v.urged into y substantially ygasetiglit- Contact` VfzitlrsaidA Verticaly wall surface.'

ReferenceswCited in the le .of `lthis patent" UNITED STATES PATENTS .y

Number i Name Date 213615623.. Guyer .etal s Oct. 131, 194e?` 2,458,468 U Sinclait letal' Ap1'.^26,=19%9.:y 2,499,805 Fahnesto'ck 1T"eb.128;f195(11v 2,522,354@ l5a`hnestock"- Sept;112,"1950f?

Claims

1. IN A GAS-HANDLING GRID FOR A VERTICAL VESSEL IN WHICH GASEOUS REACTANTS ARE CONTACTED WITH A COMPACT MOVING BED OF GRANULAR CONTACT MATERIAL, SAID VESSEL HAVING AN INTERNAL VERTICAL GRIDSUPPORTING SURFACE IN CONTACT WITH SAID MOVING BED, THE COMBINATION OF A RELATIVELY SHORT CONDUIT EXTENDING FROM SAID GRID-SUPPORTING SURFACE AND HAVING A RADIALLY PROJECTING LUG MEMBER AT EACH SIDE OF ITS FREE END, SAID LUG MEMBER HAVING ITS REARWARD FACE INCLINED DOWNWARDLY AND INWARDLY TOWARD SAID GRID-SUPPORTING SURFACE, AN INVERTED HORIZONTAL TROUGH MEMBER HAVING AN END CLOSURE PLATE PROVIDED WITH AN OPENING TO RECEIVE SAID CONDUIT, SAID OPENING BEING VERTICALLY ELONGATED TO PERMIT LIMITED VERTICAL MOVEMENT OF SAID TROUGH MEMBER WITH RESPECT TO SAID CONDUIT AND BEING HORIZONTALLY EXTENDED BY CUT-OUT PORTIONS AT THE SIDES ADAPTED TO RECEIVE SAID LUG MEMBERS, SAID WEDGE-LIKE MEMBERS PROJECTING FROM THE INNER FACE OF SAID END CLOSURE PLATE IMMEDIATELY ABOVE SAID CUT-OUT PORTIONS, THE END SURFACES OF SAID WEDGE-LIKE MEMBERS BEING SOLPED COMPLEMENTARY TO THE INCLINED SURFACES OF SAID LUG MEMBERS, THE ARRANGEMENT OF SAID LUG AND WEDGE-LIKE MEMBERS BEING SUCH THAT, WHEN SAID CONDUIT IS INSERTED THROUGH THE LOWER PORTON OF SAID ELONGATED OPENING TO A POINT WHERE SAID WEDGE-LIKE MEMBERS ARE REARWARDLY OF SAID LUG MEMBERS AND SAID TROUGH MEMBER IS RELEASED, THE SLIDING ENGAGEMENT OF SAID COMPLEMENTARY IN CLINED SURFACES WILL FORCE SAID END PLATE TIGHTLY AGAINST SAID VERTICAL GRID-SUPPORTING SURFACE.