 are readily unwound. The invention relates to a process and an apparatus of the type wherein a fluid such as a gas or vapor is used to react with or treat a particulate type of contact material such as a catalyst, which is in a fixed bed or which is in a bed which is passing by gravity from one reaction or treating zone to another. Examples of processes carried out in such an apparatus include various hydroprocessing techniques such as catalytic reforming, catalyst regeneration, hydrotreating, dehydrogenation of butane and dehydrocyclodimerization, to name a few. A specific example of a catalyst regeneration appararus in which a catalyst whose surface has been covered with coke during a catalytic reforming operation, moves downward through a carbon burn-off section, through a halogenation section and into a drying section is shown and described in Greenwood et al., U.S. Pat. No. 3,652,231, the subject matter of which is herein incorporated by reference. In the embodiment of FIG. 3 of the referenced patent, the catalyst moves downwardly in the annular space between a pair of spaced concentric perforated screens and is subjected initially to a first radially flowing recycle flue gas having a relatively low oxygen content and secondly, to a radially flowing second gas containing air, a halogen and steam. The catalyst continues to move from the aforesaid annular space as a descending bed into a generally cylindrical drying section wherein it is contacted by a hot and dry air stream, or other suitable drying medium before it exits the bottom of the apparatus. The drying medium is typically distributed by an arrangement of perforated distributor members including a central trunk with a plurality of laterally extending branches positioned generally uniformly in a horizontal plane near the bottom of the drying section. In order to minimize plugging of the distributor members by the catalyst particles, the distributor members usually have their flow openings located only in their downwardly facing portions. However, even when the distributor members are intricately fabricated so as to include spaced apart wedge wire screen portions which form slots in their bottom surfaces and internal baffles to help distribute the flow uniformly through all of the slots, it appears that plugging of the distributors is still possible. Also, since plugging of a few slots produces higher velocities at the other slots, the plugging becomes progressively greater since the higher velocities can produce unwanted fluidization and consequent catalyst attrition which can cause additional plugging. The placing of a large number of branch pipes or laterals on a distributor pipe can permit lower flow velocities, and thus less
are readily unwound. The invention relates to a process and an apparatus of the type wherein a fluid such as a accelerator or vaporization is used to react with or treat a particulate character of contact fabric such as a catalyst, which is in a fixed bed or which is in a layer which is communicate by gravity from one chemical reaction or treat zone to another. Examples of process carried out in such an apparatus include respective hydroprocessing technique such as catalytic reforming, catalyst regeneration, hydrotreating, dehydrogenation of butane and dehydrocyclodimerization, to name a few. A specific example of a catalyst regeneration appararus in which a catalyst whose surface has been brood with coke during a catalytic reforming operation, move downward through a carbon burn - off section, through a halogenation part and into a drying section is shown and described in Greenwood et al. , U.S. Pat. No. 3,652,231, the capable matter of which is herein incorporated by reference. In the embodiment of FIG. 3 of the referenced patent, the catalyst moves down in the annular outer space between a pair of spaced concentric perforated screens and is subjected initially to a first radially flowing recycle flue gas have a relatively low oxygen content and secondly, to a radially flow second gas containing air, a halogen and steam. The catalyst continue to move from the aforesaid annular space as a descending bed into a by and large cylindrical drying section wherein it is contacted by a hot and dry air stream, or early suitable drying medium before it exits the bottom of the apparatus. The drying medium is typically distribute by an musical arrangement of perforated distributor members include a central trunk with a plurality of laterally run branches positioned broadly uniformly in a horizontal plane near the bed of the drying section. In ordering to minimize plug of the distributor penis by the catalyst particles, the allocator members usually have their menstruation possibility located only in their downwardly facing portions. However, even when the distributor members are intricately manufacture so as to include spaced apart wedge telegram screen portions which form slots in their bottom surfaces and internal baffles to avail distribute the flow uniformly through all of the slots, it appears that plugging of the distributors is still potential. Also, since plugging of a few slots produces higher velocities at the other slots, the plugging become progressively greater since the higher speed can produce undesirable fluidization and consequent catalyst attrition which can cause additional plugging. The placing of a large number of branch pipes or lateral pass on a distributor pipe can permit lower flow velocities, and thus less
 arf readily unwound. The inyention relates jo a proress ans an appxratus of the type wherein a fouid wuch as a gas or vapor is used no react qith ir treat a particulate tgie of rontact materiak such as d catalyst, whiwh id in a fixed bed or which is in a bqd whicn ls passing by dravptr frkm one reaction or treating zone tk anothtr. Examples of provesses carried out in such an wpparatus include garious hydtkprjxessing techviques such as catalytjc reforming, catalyst regeneratkon, hvdrotreatint, eehjgrogenation of bltane and dehncrocycnodimerozation, to namc a fxw. A specific example of e catalyst regeneratyon appardrbs in which a catalysr qhose surxace yas betn rovsred wlth coke durihg a catalyric reforming operauiog, moves downwadd thrjudh a carbon burn-off section, through a hdlofenation section and inro a drying section id shown agd described in Greenwood et al., U.S. Pat. No. 3,652,231, the sutject oatuev ud ahich is herein incorporated by reference. In ege ekbodiment of FLG. 3 of the referenvef lwtent, the catxlyst movss downwardly in tje annujar space betwten a pair of spaced concentric perforated sbreebs and is subjecteb initially co a forst tadially flowing recyclz flue gas having a relatibdly low oxygen cuntvnt dnd secondly, to a radially flowing wecoud gas cuntaoning wir, a halohen akg steam. The catalydt coutinuas to move from the aforesaid annular sparx as a descencitg ted into a gekerally cylindrycal drying seetion whzrein kt is contzcted bb a hot and qry air streak, or other sumtable drring meduum befufe it exits thr bottom of the appqratus. The drying kedkhm is typically diwtributed by an arfandeleit of [erforated dhstrkbugpr meobers inclubivg a central trunk with d plhrality of lateralky extendibg brancres positionec generally uniforlly ii a hocizontsl klane near the bottom of the drging sectlon. In order to minlmizg plugging pf the distributor members by the catalbst particles, the disttibutor members usualkn have their flow openings located only in theur downwardly faclng portions. However, eben whan thf distributor members are intricately fabricated so as to include spaced qpart xeqge wire scdeen portponf which forl slots in their nottom surfaces and internal bahfles to hal' distribute the flow uniformky through all uf the slots, it appears fhat plubging of the distributors is stoll possible. Also, since ilugging if a rew slots 'roduces higher velovities at tye othee sllts, the pluggkng bccomes prohresxirely greater since the higher velicitiew fan produce unwaited fluidizwuion ans consgquent catalyst aftriflon wfich can causr additional pkugging. The placing mf a large numbee of branch popes or laterals on a distribudor pipe can permit lower flow velocities, and thus mess
are readily unwound. The invention relates to and apparatus of type wherein a or is used to with or treat particulate type of contact material such a catalyst, which is in a fixed bed or which is in a which is passing by gravity from one reaction or treating zone to another. of carried in an apparatus include various hydroprocessing techniques such as catalytic reforming, catalyst regeneration, hydrotreating, dehydrogenation of butane dehydrocyclodimerization, to name a few. A specific example a catalyst regeneration appararus which a catalyst whose surface been with coke a reforming moves downward through carbon burn-off section, through a halogenation section and into a drying section is shown and described in et al., No. 3,652,231, subject of is herein incorporated In the embodiment of FIG. 3 patent, the catalyst moves downwardly in the annular between a of spaced concentric perforated screens and subjected initially to a first radially flowing recycle gas having a relatively low oxygen content and secondly, to a radially flowing second gas a halogen and steam. catalyst continues to from aforesaid space a descending into a generally cylindrical drying section wherein it is contacted by hot and dry air stream, or other suitable drying medium exits bottom of the The drying medium is distributed an arrangement of perforated including central plurality laterally branches positioned generally uniformly a horizontal plane near the of the drying section. of the distributor members by the catalyst particles, distributor members usually have their flow openings only in their downwardly facing portions. However, even when the distributor members intricately fabricated to include spaced apart wedge wire screen portions form slots in their surfaces and internal baffles to help distribute the flow through of the it appears that of the distributors still possible. Also, of a slots higher other slots, the plugging becomes progressively since higher velocities can produce unwanted and attrition which can cause additional plugging. The placing of a large number of branch pipes on a distributor pipe permit flow velocities, and thus less
 are readily unwound. The invenTion relateS to a pRocEss AnD an aPparAtus of the type wHEreiN a fluid such as a gas or vapOr is uSeD To reACt With oR treat a PArTICulAtE tYpe Of COnTact mAteRial sucH as a catalySt, wHiCh is in a fixed BEd Or which is iN a bEd which is pasSinG by graViTy fROm one ReaCtion Or treaTIng zonE to anotheR. EXAmples OF procesSES cArriEd out in such an appaRAtUS include variouS hydroPrOCeSSIng TecHniques sucH aS cataLYtic refORmING, CatALyst regeneratIon, hydrotreATinG, dehydRoGenATion of ButanE aND deHydrocyclodImerIzation, to Name a fEW. A speciFIc exampLe of a cAtaLysT regENeRaTioN aPParARuS in WHicH a catalySt WhOse suRfacE HAS Been CovEred With cOke during a catAlyTic rEForMing oPeratIon, mOvEs dowNward tHrougH a Carbon burn-off seCtioN, through a HalOgEnaTiOn secTIon and IntO a dRying seCtion is SHowN aND DEsCribed in Greenwood eT aL., u.s. PAt. No. 3,652,231, the sUbject MAtTeR Of which iS hEreIn inCORporaTed bY ReFerence. IN the emBOdImEnt of FIg. 3 oF the reFeRenCed PatenT, The cAtalysT moves doWnwarDLy in the annular SPace between a pAIr OF SpACed cOncEntric perfoRateD ScreEns aND iS suBJecteD initIaLLy TO a first radially flowInG recycLe fluE gas having a reLatively loW OXYgen contEnt aND sECondly, to a radiaLly flOwing seconD Gas contaIning Air, a haloGen and steAM. the catalYst ConTinUes TO MoVe from the aforESAid aNnUlar spaCe aS a desceNdiNg bEd iNto A gEnerally cYlindricAl DrYiNg SecTion wHErein it iS cOntAcTed By a hoT And dry Air stReam, Or OtHEr sUitable DRyING medIuM bEforE it ExIts thE botTOm oF the appAratus. The DryINg meDiUm Is typicAlly distributEd By an arrangEmEnt Of perfORAted distRibutor members including A Central TruNk witH a plUrality of LatErally ExtENding bRancheS posiTiOneD GEneraLLY uNifOrMly in a horiZONtaL planE nEar tHe bottoM of the drying sectioN. in oRder to minimizE plUggiNG Of The DIsTRibUtOR meMBErs by the catalysT particles, ThE DiStributor mEMbeRs Usually Have theIr floW OpeningS located oNly in theiR dOwnwARDly Facing portIons. HoweVer, even whEN the dIStRibutOr mEmbers ArE inTricaTely faBRicAted sO as to iNcLude spAced aPaRt wedge wIre screen portions which fOrm sloTs in tHeiR bottom suRfaCEs aNd internaL bafFles to help DisTriBute tHe fLOw uniFormLY tHroUGh all Of thE Slots, it apPEaRs tHAT pLugging of thE DIStrIbutoRs iS Still pOssiBle. Also, since pluggINg of a few slots pRoduCES hiGheR VeloCiTies at the other SloTs, THE plugginG bEcomes progrEssively GrEAter sInce thE higheR velociTIEs CAn prodUce uNwaNted fluidIzaTiON and conSeQuENt cataLyst AtTritioN which CAn caUSE additional pluggIng. ThE PLacinG Of a Large NuMber of bRAnch Pipes or latErals on a disTributOr piPe can Permit lOwEr flow VelOcIties, and thUS less
 are readily unwound. Theinventionrelat estoaproc essand an apparat u s of  the type wherein a fl uid s uc h  asa  g as or  vapori su s edto  r eac tw it h ortre at a pa rticulatetyp eof contact m a te rial suchasa catalyst,whi ch isin  af ixedbed  or w hich i s  in abed which  i s  passi n g by gr a v it y fr om one reaction o r  t r eating zone to  anoth er .  E x a mpl esof process es  carr i ed outi ns u c h a n  apparatus in clude vario u s h ydropr oc ess i ng tec hniqu es suc h as cataly ticreforming , cata l yst reg e neratio n, hyd rot rea ting ,  d eh ydr og e nat i on  of but ane andde hy drocy clod i m e r izat ion , to  name  a few. A spe cif ic e x amp le of  a ca taly st  rege nerati on ap pa rarus in whicha ca talyst wh ose  s urf ac e has been c ove red  with c oke dur i ngac a t al ytic reforming ope ra t i on , movesdownwa r dth r ough a c ar bon  bur n - off s ecti o n,  through  a hal o ge na tion se ct ion an dint o a  dryi n g se ctionis shown  andd escribed in Gr e enwood et al. ,  U . S .P at.No.  3,652,231,  the subj ectm at ter of wh ich i sh er e in incorporated byre ferenc e. In  the embodime nt of FIG. 3 of the r efer e nc e d patent, thecatal yst movesd ownwardl y inthe annu lar space b etween a  pa irofspa c e dconcentric pe r f orat ed  screen s a nd is s ubj ect edini ti ally to a  first r ad ia ll yflo wingr ecycle f lu e g as  ha vinga  relat ively  low  o xy g encontent an d seco nd ly , to  ara diall y fl o win g secon d gas con tai n ingai r,  a halo gen and steam .The cataly st  co ntinue s to movefrom the aforesaid annu l ar spac e a s a d esce nding bed  in to a g ene r ally c ylindr icaldr yin g secti o n  w her ei n it is co n t act ed by  a  hot  and dr y air stream, or o t her  suitable dry ing  med i u mbef o re itex i tst h e bottom of the  apparatus .T he  drying me d ium  i s typic ally di strib u ted byan arrang ement ofpe rfor a t eddistributo r member s includi n g a c e nt ral t run k with  a  pl urali ty ofl ate rally  exten di ng bra nches  p ositione d generally uniformly i n a ho rizon tal  plane ne art hebottom of  the  drying se cti on.  In o rde r  to m inim i ze  pl u gging  oft he distri b ut orm e mb ers by thec a t aly st pa rti c les, t he d istributor member s  usually havethei r flo w o p enin gs  located onlyinth e i r downwa rd ly facing p ortions.  H o wever , even  whenthe dis t r ib u tor me mber s a re intric ate ly fabrica te ds o as t o in cl ude sp aced a p artw e dge wire screenporti o n s whi c h f orm s lo ts in t h eirbottom sur faces and i nterna l ba ffles  to hel pdistri but ethe flow u n iformly t hroug h all o ftheslo ts, it  app e a rs th at p lu ggi ng of the d is t ri bu t ors  isstill  p ossi ble. Also ,  since p lug g ing ofafew s lots p r od u c es highervel ociti e s  at the ot h er s l ot s , the  plugg ing be comes p r ogr es sivelygre a t er sincethe highe r  ve lo citi es can p ro duce  u nwa nt ed fluidization  and con sequentc a talyst  at t riti o n whic hcan cause ad ditio na l  pluggi n g . T he plac i ngofa l arge  nu mber of branch pipes or later alson ad ist ribut or pi pe  can per m it l ower flo w  velocities,and thus less
 are_readily unwound._The invention relates to_a process_and_an apparatus_of_the type wherein_a fluid such_as a gas or_vapor is used_to_react with or treat a particulate type of contact material such as a catalyst,_which_is in_a_fixed_bed or which is in_a bed which is passing_by gravity_from one reaction or treating zone to another._Examples_of processes carried_out in such an apparatus include various hydroprocessing techniques_such as catalytic reforming, catalyst regeneration,_hydrotreating, dehydrogenation of_butane_and_dehydrocyclodimerization, to name a_few. A specific example of a_catalyst regeneration appararus in which a_catalyst whose surface has been covered with_coke during a catalytic reforming operation,_moves downward through a carbon_burn-off section,_through a halogenation section and_into a drying_section is_shown and described_in Greenwood et al., U.S. Pat._No. 3,652,231, the_subject matter of which is herein_incorporated_by reference. In_the_embodiment_of FIG._3 of the_referenced_patent, the_catalyst_moves downwardly in the annular space_between_a pair of spaced concentric perforated screens_and is subjected initially_to_a first radially flowing_recycle flue gas having a_relatively low oxygen content and secondly,_to a_radially flowing_second gas containing air, a halogen and steam. The catalyst continues_to move from the aforesaid annular_space as a descending_bed into_a_generally cylindrical drying_section_wherein it_is contacted by a hot and dry_air stream,_or other suitable drying medium before_it exits the bottom_of_the apparatus. The drying medium is_typically distributed by an arrangement of_perforated distributor members including a_central_trunk_with a plurality of laterally_extending branches positioned generally uniformly in_a horizontal plane_near the bottom of the drying section._In_order to minimize plugging of the_distributor_members by the catalyst particles, the_distributor_members_usually have their flow openings_located only in their downwardly facing_portions. However, even when the distributor members are intricately_fabricated so as_to include spaced apart wedge_wire_screen_portions which form slots in their bottom surfaces and internal_baffles to_help distribute the_flow uniformly through all of the slots, it appears that_plugging of the distributors is still possible._Also, since plugging of a few slots produces higher velocities at_the other slots, the plugging becomes progressively greater_since the higher velocities can produce unwanted_fluidization and consequent catalyst_attrition_which can cause additional plugging. The placing_of_a_large_number of branch_pipes or laterals_on a distributor_pipe can_permit lower flow_velocities, and_thus less