Патент USA US2403486код для вставки
July 9, 1946. J. M. BARRON 2,403,486 COMBINATION CATALYTIC AND THERMAL CONÑ‘ÍERSIONA Filed Dec. 19, 1944 ‘ 2,403,486 Patented July 9, 1946 UNITED STATES PATENT OFFICE 2,403,486> COMBINATION CATALYTIC AND THERMALv CONVERSION `loseph Mason Barron, Port Arthur, Tex., assignor to The Texas Company,¿NeW York, N. Y., a cor poration of Delaware Application December 19, 1944, Serial No. 568,886 6 Claims. (Cl. 196-f49l l This invention relates to the combination cata lytic and thermal conversion of hydrocarbons and contemplates particularly a method of processing high boiling or residual petroleum stocks to ulti mate yields of coke and high antiknock gasoline` or motor fuel. A 2 such as crude oil or topped crude containing a large content of gas oil is introduced by a pump I0 to heating coil II whereinrit is heated to a cracking temperature. The heated eiliuent is di rected through a transfer line I2 to the upper portion of a reaction chamber I3. Highly heated vapors and gases enter the lower portion of the reaction'chamber through a line I4. The reac-ï In accordance with the invention, petroleum stocks such as crude oils and topped crudes are contacted with highly heated light stocks of the tion Vchamber is maintained at a high cracking tained under superatmospheric pressure and at a cracking temperature. The contacting of these a superatmospheric pressure such as v20G-60d p. s. i. The downilowing liquid is subjectedto nature of gasoline or naphtha as well as normally 10 temperature of theorder of 900° F. by reason of the heated entering ñuids and maintained under gaseous hydrocarbons in a reaction zone main countercurrent contacting with the- upwardly> obtain thermal conversion of the intermingled 15 rising vapors at the high temperature, in a zone free from bañles or other obstructions, to not only constituents and also to obtain maximum vapori produce cracking but also to cause `maXimum zation so that the separated vapors will contain vaporization. Liquid is prevented from accumu not only the gasoline components but'also the lating by rapid withdrawal from the chamber bulk of the gas oil constituents. The thermal cracking to which the constituents are subjected 20 through a line I5 and it is, in fact, best to'oper ate the reaction chamber “dry," that is, without in the reaction chamber functions particularly to any liquid level therein. » „ Y crack paraiiìns and concentrate naphthenes and The separated vapors pass from the separating aromatics to produce good material for a succeed and cracking chamber I3 through a vapor line I6 ing catalytic cracking step. Products vaporizedk in this combination cracking and separating step 25 to a catalytic cracking zone I1 wherein the vapors dissimilar stocks is conducted in s_uch a way as to constitute the charging materialfor a succeeding catalytic cracking step. The residual product from the thermal cracking and separating step is sub jected to coking and vapors evolved in the coking , are subjected to catalytic conversion in contact with a solid comminuted or pulverulent catalyst.V The contacting of the vapors and gases with the catalyst may beaccomplished in various ways„` 30 such as passing the vapors through a stationary bed of catalyst, passing the vapors over a con ing fractions from higher boiling fractions. . The operation are fractionated to separate lower boil lower boilingvfractions, after being subjected to tinuously moving mass of granular catalyst, or thermal conversion or reforming, are directed to the thermal cracking and separating Zone for. in the stream of gases and vapors for conversion promoting the vaporizing and cracking of the re sidual charging stock. Higher` boiling fractions from the coking operation are passed through a heating zone and subjected to thermal cracking. Higher boiling fractions obtained in fractionating l the catalytically cracked products are likewise passed through a heating zone and subjected to thermal cracking. The thermally cracked prod ucts from these two heating zones are combined and the mixture is subjected to catalytic crack ing, Normally gaseous hydrocarbonsrecovered from the combination process arersubjectedl to thermal conversion and then directed to Vthe by suspending finely divided or powdered catalyst;v under iluid catalyst conditions. The preferred catalysts are the silica-alumina catalysts, such as` in the form of activated clays or as synthetic pre cipitated composites vof silica and alumina. When using the catalyst in the form of iixed beds a plurality of catalyst cases are employed which may alternate on processing and regenerating in a well-known manner, and when using catalyst suspended in the vapor stream or under ñuid catalyst cracking conditions, the catalyst may be f continuously withdrawn for regeneration. Thev vapors and ïgases are contacted with the catalyst at temperatures such as 800-1000° F, under mod- - thermal cracking and separating Zone or com erate superatmospheric pressures, preferably not` invention, reference is had to the accompanying drawing which is a flow diagram illustrating Aa while at the vsame time recombination reactions with the gaseous hydrocarbons and catalytic re exceeding about 100 p.V s. i_` to affect the catalytic bined with the vapori'zed eñluent therefrom, which passes to the catalytic cracking stepV mentioned. 50. cracking of higher boiling hydrocarbons into lower boiling products of gasoline boiling range, For` the purpose of completely disclosing the` particular embodiment of the invention; . Referring now to the drawing, charging stock `ist. formingof gasoline constituents takes place. The products ofthe catalytic conversion pass" 2,403,486 3 4 through a transfer line I8 to a fractionator I9. mary section 20 and a secondary section 2I sepa rated by a condensate tray 22 and the transfer line I8 is branched so that the catalytically cracked products may be delivered to either the line 45 to a heating coil 46 wherein the oil is subjected to conditions of thermal cracking. In the cracking coils 42 and 46 the oil is subjected to temperatures such as 900-10G0° F. with coil outlet pressures of from 400-'700 p. s. i. to produce extensive thermal conversion. The particular primary or secondary fractionating zones. The fractionator is provided with suitable cooling and conditions obtained in the cracking coils 42 and 46v may be varied in accordance with the char The fractionator is preferably formed with a pri refluxing means so as to take off as vapors a prod acter of the stocks directed to these coils, but in uct of desired end point, as for example, 400° F. 10 general the catalytic gas oil being cracked in coil end point for ordinary motor fuel or 375° F; end 46 will stand a soaking volume factor of from point for aviation motor fuel. The overhead va 5-'7 (basis '750 p. s. i.) at about 950° F. heater outlet temperature, and the gas oil from the cok ing operation being cracked in coil 42 will stand pors are condensed in a cooler 23 and the distil late is collected in a distillatedr'uni or gasïsepa rato;1 24. ` Referring now to the disposition of the residue withdrawn from the reaction chamber I3 through line I5, this residue is directed through a pres sure reducing valve 25 to a coking drum 26. By 15 a soaking volume factor of 8-10 with a coil out let temperature of about 1000° F. In the crack ing coils 42 and 46 extensive thermal conversion takes place which involves particularly the crack ing of oleñns and paraihns, with the result that reason of the manner of contacting the heavy 20 the effluent from these cracking coils is 4of re stock with the light stream of gases and vapors duced parafñnicity and contains high concen ink the reaction chamber it is possible to main trations of oleñns, naphthenes and aromatics. tain the liquid residue being vwithdrawn at a The thermal cracking not only produces gaso suflicient temperature and sufliciently free from line but also yields higher boiling components of gas oil constituents that this residue may be 25 increased susceptibility to catalytic cracking. flashed to coke in the coking drum solely by its The effluent from the thermal cracking coils contained heat. While any deficiency in heat 42 and 46 is combined in a transfer line 41 which may be overcome by including a portion of the vapors with the residue withdrawn from the re mixture is subjected to catalytic cracking in con action chamber, it `is preferable to maintain the ’ tact with cracking catalysts, such as any of those quantity of vapor thus withdrawn at a minimum and to rely on the temperature of the liquid resi due to accomplish vautogenous- coking. By with drawing the residue at temperatures around S20-930° F. conversion to a marketable coke may be accomplished by flashing solely by the con tained heat of the residue. In practice, a plu rality of c-oking drums are employed so as not to leads to a catalytic cracking zone 48 wherein the previously mentioned, in accordance with any of the several methods which have been outlined forv the _catalytic cracking Zone I1. The mixed stocks subjected to catalytic cracking undergo various reactions including conversion into lower boiling hydrocarbons accompanied with exchange reac tions and cyclization functioning to form con stituents in the gasoline boiling range of high antiknock quality. And the oleñn content of the interrupt the continuity of the complete process. The coking drum is maintained at loW pressure 40S gasoline constituents, formed by the preceding such as 50 p. s. i. down to approximately atmos thermal cracking, is reduced. pheric pressure. ` The catalytically cracked products are directed The vapors evolved in the coking‘drum pass through a line 49 to the fractionator I9 or more through a vapor line 21 to a fractionator 28 which i particularly to the fractionating section 26 there is preferably formed with a primary section 29 ~ of. The effluent from the catalytic cracking zone and a secondary section 30, separated by a con 48 will generally contain some higher boiling con densate tray 3l, with the vapor line entering the stituents of a somewhat more refractory nature primary' fractionating zone 29. In the latter frac than those _contained in the eflluent from the cata tionating vzone the vapors are subjected to a pri lytic cracking ’zon'e I1 and consequently it is or 50' mary dephlegmation at relatively high tempera dinarily desirable to direct the products from the tures' approximating 800° F. throughout the zone cracking zone 48 to the primary separating sec to separate out the synthetic tar. This tarry tion 20 while delivering the products from crack product may be withdrawn as a fuel oil product ing Zone I1 to the secondary fractionating section through line 32 or directed by a pump 33 to the 2|. A quantity of residue may thus be separated coke drum 26 for conversion to coke. The gasv 55 in the dephleämator 29 which may be withdrawn oil condensate is collected on the tray 3l; the through a line 50. This residue may be removed naphtha vapors'pa'ss'to a cooling coil 34 for con from the system as a product of the process or densation and the naphtha distillate is collected it vmay be sent to the fractionating Zone 29 for in a receiving drum or gas separator 35, having re'fractionation therein. Y a Vgas line 36 which may extend to a low pressure en The ultimate gasoline product resulting from gas` recovery system (not shown). n the combination of the several thermal and cata The coke still naphtha is lwithdrawnfrom the receiver 35 -and directed by pump 31 through lytic conversion processes described herein is col lected in the receiving drum 24, This distillate may be withdrawn from the receiving drum and line38 to a heating coil 39 wherein it is subjected to/thermal reforming at temperatures such as 65 directedAv by ,pump 5I through line 52 to a sta 900-1050° F. under pressure such as 400-600 p. s. i. The vaporous products of conversion Yare directed bilizer 53. Uhcondensed vconstituents are re moved from the receiver 24 through a line 54. through the transfer line I4 to the lower portion On account of the relatively low pressure exist of >the reaction chamber I3. ing in the receiver 24 the gases will contain con Condensate from tray 3| is directed by a pump 70 siderable quantities of hydrocarbons adapted for 40 through line 4I to a heating coil 42 wherein inclusion in the gasoline product. To recover the condensate is subjected to conditions of ther these constituents the gases flowing in line 54` mal cracking. The catalytic gas oil collected on may be diverted to a 'pump or compressor 55 by the tray 22 of fractionator I9 isl withdrawn which the gas may be placed under several hun- ' through a line 43 and ydirected by pump' 44 through 75 dred poundsvv pressure and directed through a espansa 6 petroleum and‘containing both residual and gas 0001er 5.6 te. a. drip v,drum- 51; .from lwhich . con densate (may be withdrawn through _a line 58 and sent to the ,stabilizer 53. rIfhe latter- is provided o'il¿_ components thereof, the process " that com prises introducing said charging> stock to a reac with suitable` cooling, refiuxing vand reboiling means *_ (not shown) for rectifying the gasoline tion chamber, passing naphtha through a heating zone ‘wherein it is heated to a cracking tempera distillate, the final stabilized product being with drawn through _a line 59. Uncondensedconstitu ents Spass through cooler 50 to a distillatedrum 6|V from which uncondensed gases are removed ture and. subjected to reforming, introducing the heatedA naphtha into said reaction chamber’to> subject the residual stock to> cracking and vapori zation, passing _separated vapors from the reac tionchamber to a'catalytic cracking zone where throughaline62._ y I , o L l . `„v _ 10 The distillate. collecting in> drum 6| under pres sures of .ZOO-400 p. s. i. consists largely or essen-_ tially of 'C3 and C4 hydrocarbons.v '_I‘hese nor Inally gaseous constituents Yare. _directed by a pump A63 through a line 64, thence through a in the vapors are subjected to >catalytic crack ing, fractionating the y resultant catalytically cracked products in a fractionating zone to sepa rate higher boiling from lower boiling products, 15 branchline 65 to heating coilA 66 or through a branch line 6l tol heating coil 68, or a portion of thezgases may be directed to each of these heat ing coils. The gases are subjected inthese heat ing coils to high conversion temperatures of the 20 order of 1000°`F.-1100° F. under 400-800 p. s. i. to ' eifect'the cracking of parañîns as well as the passing the higher boiling products to a heating zone wherein they are subjected to cracking tem perature with su?licient time of reaction to ef fect extensive thermal cracking including the, cracking of oleñns and paran-ins, withdrawing re,-~ sidual products from the reaction chamber'and subjecting them to coking, fractionating the vapors from the coking operation to obtain Aa lower boiling fraction comprising gasoline con polymerization of oleñnic constituents. The ef fluent> from gas conversion> coil 6B is delivered stituents and a higher boiling fraction, directing through a transfer line 69>to the lower portion 25 said lower boiling fraction to the aforesaid heat of the reaction- chamber I3, `together with’the in_g'zone- for reforming therein, directing _said eiliuent from the naphtha reforming coil 39. The higher boiling fraction to a heating zone where in it is heated to a cracking temperature and sub eil‘luent from the gas conversion coil 68 is deliv jected to extensive thermal cracking including ered through a transfer line 10 to the vapor -line IS. The stream from the coil 68 may.- thus serve 30 to increase the temperature of the vapors flow ing fromV the reaction chamber to the catalytic cracking Zone lvl and Aalso to vary the space ve locity or time of contact of the Vhydrocarbons with the catalyst. - - t ~ the cracking of olefìns and paraffins, combining the resultant heated products of reduced paraf ?inicity from said thermal cracking operations and subjecting the mixture vto catalytic cracking and >passingthe resultant catalytically cracked 35 product to said fractionating zone. _ ` y v3v. In the combination thermal and catalytic Although apreferred embodiment of the> in vention has been described herein, it will be un derstood that various changes and modiñcations may be made therein, while s_ecuring to agreater or less extent some or all of the benefits of the cracking of hydrocarbon oils for the unitary proc essing of a charging stock obtained from crude petroleum and containing both residual and-gas oil components thereof, the process that com invention, without departing from the spirit and prises passing lower boiling fractions ‘through a scope thereof. heating zone wherein they are heated to a crack-_ vIclaim: l ~ . „ ' » . A . i Y ingte'mperature, directing the resultant heated products to the lower portion of a vertically vdis cracking of hydrocarbon oils for the unitary 45 posed reaction chamber maintained under super atrnospheric pressure and wherein separation of processing- `of av charging stock obtained from vapors fromwliquid residue takes place, intro crude petroleum and containing both residual dncing saidycharging stock to the upper portion and gasoilV components thereof, the processr that of the vertically disposed reaction chamber, sub comprises introducing said charging stock to a reaction chamber, passing lower boiling hydro 50 jecting the down-flowing liquid and upwardly rising vapors to countercurrent contacting with carbons through a heating zone wherein they are in the reaction chamber at cracking temperature, heated to a cracking temperature, directing the passing separated vapors from the reaction resultant heated products to said reaction cham chamber to a catalytic cracking zone wherein ber to subject the residual stock to cracking and suchofractions are subjected to catalytic crack-_ vapori-zation therein,_ passing. separated vapors ing, withdrawing residual products from the re from the reaction chamber to a catalytic cracking action chamber and subjecting them to coking, zone wherein such fractions are subjected to cata fractionating vapors evolved from the coking lytic cracking, withdrawing residual products operation to separate light fractions from higher from the reaction chamber and subjecting them to coking, fractionating vapors evolved from the 60 boiling fractions, directing said light fractions coking operation to separate lighter fractions to the aforesaid heating zone for conversion, sub from higher boiling fractions, directing said jecting said higher boiling fractions to cracking '1. In the combination thermal and catalytic lighter fractions to the aforesaid heating zone temperature with suñîcient time of reaction to ef for conversion, subjecting said higher boiling fect extensive thermal conversion including the fractions to cracking temperature with su?licient 65 cracking of oleñns and parañins, subjecting the time of reaction to effect extensive thermal con resultant thermally cracked products of reduced version including the cracking of oleñns and parainnicity to catalytic cracking and fraction paraii‘ins, subjecting the resultant thermally ating the products produced in the catalytic cracked products of reduced paraiiînicity to cata cracking operations to recover the catalytically lytic cracking and fractionating the products 70 cracked gasoline. produced in the catalytic cracking operations to 4. In the combination thermal and catalytic recover the catalytically cracked gasoline. cracking of hydrocarbon oils for the unitary 2. In the combination thermal and catalytic processing of a charging stock obtained from cracking of hydrocarbon oils for the unitary proc crude petroleum and containing both residual essing of a charging stock obtained from crude 75 and gas oil components thereof, the process that 2,403,486 7 8 compr1ses passing naphtha through a heating passing the separated vapors to a catalytic crack Zone wherein it is heated toY a cracking tempera ing zone wherein the vapors are subjected to catalytic cracking, fractionating the resultant ture and subjected to conversion, introducing the catalytically cracked products in a fractionating zone to obtain'fractions comprising a normally heated ynaphtha into the lower portion'of a ver tica-lly disposed reaction chamber maintained un der superatmospheric pressure and wherein sep gaseous fraction, a gasoline fraction and a higher boiling fraction, heating the normally gaseous fraction to subject it to thermal conversion and aration of vapors from liquid residue takes place, heating -said charging stock to cracking temper directing the resultant conversion products into ature and directing the heated oil tothe‘upper portion Íof the vertically disposed reaction cham 10 the lower portion of said vertically disposed re actionchamber, heating the higher boiling irac ber, subjecting the downño‘w liquid and upwardly tion to a cracking temperature to subject it to rising vapors to countercurrent contacting with’ thermal cracking, withdrawing residual products in the reaction chamber at cracking temperature, from the reaction chamber and subjecting them passing the separated vapors to a catalytic cracking zone wherein the vapors are subjected to coking, fractionating the vapors from the cok ing operation to obtain a lower boiling fraction containing gasoline constituents and a higher boiling fraction, directin‘g said lower boiling frac to catalytic cracking, fractionating the-resultant catalyti'cally cracked products in a fractionating zone to separate higher boiling from lower boil ing products, subjecting the higher boiling prod ucts to cracking temperature with suiîicient time of reaction to'e?fect extensive thermal cracking including the cracking of ole?ìns and parafñns, withdrawing residual products from the reaction chamber and subjecting them to coking, irac tion to the aforesaid heating zone for reforming therein, directing said higher boiling fraction to a heatingA zone wherein it is heated to a crack ing temperature and subjected to thermal cracking, combining the resultant heated prod ucts from said thermal cracking operations and subjecting the mixture to catalytic cracking and passing the resultant catalytically cracked prod tionating the vapors from the coking operation to obtain a lower boiling fraction containing gas oline-,constituents and a higher boiling fraction, directing said lower boiling fraction to the afore» said heating zone for reforming therein, direct ucts to said iractionating zone. 6. In the combination thermal and catalytic cracking of hydrocarbon oils the process that comprises introducing a heated' residual 'stock to a reaction chamber, passing lower boiling hydro ing said higher boiling fraction to a heating zone - wherein it is heated to a cracking temperature and subjected to cracking temperature with suf ñcient time of reaction to effect extensive ther mal conversion including the cracking of ole carbons through a heating zone whereinl they are heated to a cracking temperature, directing the resultant heated products to said reaction cham ñns andparaiiins, combining the resultant heat 35 ber to subject the residual stock to cracking and vaporization therein, passing lighter fractions ed products of reduced parafñnicity from said evolved from the reaction chamber to a catalytic thermal cracking operations and subjecting the cracking 'zone wherein such fractions are sub mixture to catalytic cracking and passing the jected to catalytic cracking, withdrawing resid resultant catalytically cracked products to saidr fractionating zone. 40 ual products from the reaction chamber and subjecting them to coking, fractionating vapors evolved from the coking operationV to separate lighter fractions from higher boiling fractions, 5.7Inv the combination thermal and catalytic cracking of hydrocarbon oils the process that comprises passing naphtha through a heating directing said light ‘fractions -to the aforesaid zone wherein it is heated to a cracking tempera ture and lsubjected to conversion, introducing the l heating zone for conversion, subjectingfsaid high heatedA naphtha into the lower portion of a ver tically disposed reaction chamber maintained'un der superatmospheric pressure and wherein sep aration> of vapors from- liquid residue takes place, heating a residual stock to cracking tempera 50 er boiling fractions to thermal cracking, subject ing the resultant thermally’cracked products to catalytic cracking and fractionating the products produced in the catalytic cracking operations to recover the catalytically cracked gasoline and a ture and directing the heated cily to the upper normally- gaseous fraction, heating the normally portion of the vertically disposed reaction cham ber, subjecting the downiiow liquid and upwardly rising vapors to countercurrent contacting with in the> reaction chamber at cracking temperature, gaseous fraction to-subj'e'ct it to thermal conver sion and directing the resultant conversion prod uct’s to saidreaction chamber. JOSEPH IMASON BARRO'N.