US2775546A - Conversion of hydrocarbons in the presence of inert solids - Google Patents

Description

Dec 25, 1956 c. N. KIMBERLlN, JR., ETAL 2,775,546

CONVERSION OF HYDROCARBONS IN THE PRESENCE OF INERT SOLIDS 4 Sheets-Sheet l Filed June 20, 1951 T @H E o w@ c n. n C VV w n c 5 n: ub w.; hun .mm f3 M nr 5e eb u@ o Q Dec. 25, 1956 C. N. KIMBERLIN, JR., ET AL CONVERSION OF HYDROCARBONS IN THE PRESENCE OF' INERT SOLIDS 4 Sheets-Sheet 2 Filed June 20, 195] Dec. 25, 1956 c. N. KIMBERLIN, JR., ET A1. 2,775,546

CONVERSION OF HYDROCARBONS IN THE PRESENCE OF INERT SOLIDS Filed June 2O 1951 4 Sheets-Sheet 4 @harLeS QKimberUn J Bru/enters United States e. non li:

This invention relates to a process for treating hydrocarb.onsand.moreparticularly relates to the conversion 1oricracking of-.heavyresidual petroleum oil to p1'oduce .lowerrboiling:hydrocarbons. 4 v

The petroleum oil residuumor residual oil which is to beeonvertedcaccording to the present process is ahigh boiling-.hydrocarbonoil `which cannot bewvaporized.` at ordinary. pressures without cracking. the high boiling con- .stituentsr. .Atvpresent there is a 4relatively/largev accumuglation of'reduced icrudegor heavy bottoms becausey lower l.grade .crude..oil feedstocks are being-processed 'which .leave morev residue andbecause there is a` larger demand "for .motorffuelsuch as 'gasoline .and other petroleumfoil products. such ,asheating'oil which meansprocessing frnore .crude` :oil to leavetmore residue.` Also .the tendency .is todistill the crudes to recovenhigher boiling, feedstocks .diofrv-oatalyticwcracking and. this leaves higher boiling residualbils. f f A u f nv-It-isknown to crack or coke heavy residual petroleum oils `in thepresence.oiiinely` divided inert solid particles maintained as..a.uidized bed. `Such colingis diilcult to operate at relativelylow temperatures. except ativeryllow ,efeed ratesdueio tle-..sticky feedcausingloss ofjluidity in the-bed of solids. .In delayed colcing, the-,process is Adiscontinuous and: lpresents a problem oi ,removingwgcoke -ronr the coking vessel.. AnotherY known processofpQksing is.one.wherethe, residuum is sprayed ontoa moving fbedrofhot coke .but this process ,requires large and yeX- v pensive equipmentand :is inoperable below about 930 exceptat .very -low-residuum feed rates-because of-.fthe 1' bridging yof .themoving coke bed-, by .the stickyresiduum ,-feedL f .;1 1 n." r. A.' ..:.-Qther conversion processesy are known wherein the residuum or heavy petroleum residualoil is-heated in a :g ,coil fand/or. .soaking :f,drum under.. sufficient,Y pressure to prevent 7distillationo the gas oil asitis ,produced but, in this type otr-.process the coke-,remains largelywsuspended theeoil. and the only means. available,heretoiorehas been lti'ation or centrifuging to remove the ookefparmticles; neither of whichds desirable. `When operating at ,-:desirably L-highconversions the. reaction vproducts directly`from .the conversion vzonecannot befed directlydo a `distillation zonedue, tothe high-.content ofucoke which 1..would resultin fouling of the Vdistillation equipment,

u The..pre`sentinvention `overcomes Ytheobjections `and shortcomings of prior process by providing`- an improved distillation zone for the, productsofconversion leaving jithe coking zone. The productsof conversion orcolring are flashed or sprayedinto or onto .a lluidized bed of ^heatediner-t solids, preferably coke particles. The uid- "likedv bed of solids is maintained at a temperature of about 900 F. to 1050 to rapidly vaporize the distillable oil leaving thelcoke particlesY behind in the ludized bed.

wgfhelheated fluidized bed of solids acts as a distillation -zone primarily and not as a `coking or conversion zone.

Vrious`modications of the inventionare presented Va williappearrfrom the detailed description to be given after.

`for vacuum residua. 30

2,775,546 atented Dec. 25, 1956 ICC In the drawings:

Fig. .1 represents one form of apparatus adaptedto carry outrthe process of the invention;V i

.Fig 2 represents a modification in which some of the coke is burned inthe distillation zone and heat issupplied to the coking step by submerging a coking coil inthe iluidized bed in the distillation `zone; v

Fig. 3 represents a modification where some of the coke isburnedrin a coil submerged in the iluidized bed inthe distillation zone to `indirectly supply heat tothe distillation zone; and v Fig. 4 represents another modification in which the iluidized solids bed distillationzone is maintained under vacuum. l

Referring now to Fig. 1 of the drawings, the reference characterltldesignates a line` for feeding heavy residual petroleum oil', to a preheating coil 12 anda coking or conversion Vzone 14 which may bea coil or coil and drum or a drum for icokingthe residual `oil and to produce vcokegas and distillable oils including gasoline, heating 4whole petroleum crude oil, ,tars, pitches, s hale oil, heavy cycle oil, etc, The residual oil mayhave a gravity of about l'0 to 20 API anda Conradson carbon ofabout 5 to 30 wt. percent andan initial boiling point above about 800 F.` for atmospheric residua or above about 1050 `F.

The oil is heated in coking zone 1d to a temperature of about 750 to 950 and is -nfiainntained under a pres- (sure of about 100 to 3000 pounds persq. in.` gage with the residence timerbeing-about 2 Vto`240 minutes depending onthe vtemperature selected and the degree* of conversion desired. ToF avoid coke adhering `to the internal walls ot 'the coil` or drumvit isrpreferred to add nely divided solids preferably coke of a size of about 5 toV 250 microns to the oil feed through line 16 to serve fas nuclei upon which coke formed during colingis deposited. vThe added coke particles also act toV scour andclean the walls ofthe-coking zone. The amount of solids added through line ld is about l5 to .100 lbs. per barrelof yoil..fered, preferably about 30 to 60llbs.` per-barrel.

A diluentsuch as steam orllowerl boiling kpetroleum fractions maybe added to theresidual oil feed through K -line` `1&5 to aid in vaporization of the residual oil'or tonirnv#prove product distribution inthe' coking Vzone and to improve volatilityffin the iluidfdistillation zonen When processing theVery heavy vacuum residual oils, itjis, particularlydesirable to add a diluent of lower'bQiling petroleum fraction such as a heavy naphtha'boiling in 'the rangeor" about' 250 to 5001 F. This naphtha diluentlmay be added in amounts' of 20 to' 120 vol. vper- ;Cent, preferably'rabout 50 to 100 vol. percent of the residual'oil to be processed. rThis naphthadiluent decreases' the `viscosity of the residual oil.thus permiting greater turbulence and a 'more `effective scouringaction on the vessel walls by the seed coke with the resultthat foulingofthe wallsis avoided. t

r The total products of conversion or coking inthe iorm of a slurry of coke in liquid oil leave coking zone`f14 through line'22 and are passed toa'uidized solids dis- -tillation zone 24 -maintained at a temperature of about 800 to 1050 F.V and under a pressurefof about 0 to 25 lbs. per sq. in. gage.y Substantially all of the cracking or coking has taken place in` coking zone 14 so that the tainsfthe bed iluidized having a level indicated at 28 with a dilute phase 32 thereabove. The density of the fiuidzed bed when using nely divided coke having a particle size of about 100 to 400standard mesh is about l5 Ito 40 lbs. per cu. ft. Preferably a gas-solids separating meanssuch as a cyclone separator (not shown) is arranged in the upper part of the distillation zone 24 to remove etrained particles from the vaporous .products leaving the distillation zone 24 through outlet `line 34 and return them to thewden'se b'ed 26.

The total products o'f coking from line 22 may pass through pressure reducing valve 35 in line 36 where they 'are dashed or sprayed through a spray nozzle device 38 'above llevel 28 and onto the top of dense fluidized bed 26 `1-11 d1st1llation zone 24. Due to the reduction in pressure some .of the coking products are immediately flashed or vaporized and pass overhead through line 34 to a fractionatcr tower r42 presently to be described. The nonvaporiz'ed constituents drop into the fluidized bed 26 and me ve'poiiz'ed and pass overhead through line 34 to leave 'only the coke particles in the bed 26. Alternatively, the total products of :colcing may be passed through line 44 anto ruidizedbed 26 below the level 28 thereof.

For supplying heat to the distillation zone '24, lluidized Y 'coke or solid particles containing coke formed during cokng and coking vessel `14 are withdrawn from 4the bottom of distillation zone 24 by means of a standpipe 46 having a control slide or other valve 48 to control the rate of Withdrawal* of solids from zone or vessel 24. The with- `drawn. solids yare picked up by air or other oxidizing gas lintroduced through line i512 .and the resulting suspension .passed through line 54 into the lower portion of a burning o r heater vessel 56 provided with a dense fluidized `-turbulent bed 58 of solids having a Ilevel indicated at '62 :with la dilute phase 6-4 thereabove. The supericial Velocllty bf the gasiform material passing upwardly through some solids which are carried over into the fractionator 42through line 34.

Referring now to Fig. 2 of the drawings, the reference character 102 designates a feed line -for the heavy residual oil feed into which steam or light petroleum oil diluent may be 4introduced through line 104, bottoms recycle through line 106 and coke particles to serve as nuclei for coke and for scouring the coil heater 108 introduced through line 1512. Steam may be used .as the carrying gas for said coke as shown in line 113. The residual oil admixed vwith other materials passing through preheater 108 is then passed through coil heater 112 most of which is submerged in uidized solids bed =114 in distillation vessel 11-6. -The dense fluidized highly turbulent bed 114 has a level indicated at 118 .above whic-h is .a disperse or dilute phase 122. The oil passing through coil heater 112 is heated to colting temperatures of about 900 F. to 1000 and is maintained under a pressure of about 500 to 3000 lbs. per sq. in. gage and the residence time of the oil in heater 1112 is about 2 to 5 minutes.v The oil 'in heater 112 receives heat from the dense fiuidized bed 114 by indirect heat exchange.

The upper or outlet end of coil heater CD12 extends abo-ve the level 118 in vessel 116 and at its extremity is directed downward and provided with a nozzle member 124 for spraying .the liquid products `of colcing onto the bed 114. Adjacent nozzle member 124 the upper end of vessel 5'6 is selected to be between about 0.5 and 2.5 feet l -per second to give a density of the bed of about l5 to 40 lbs. per cu. .f-t. when using 100-400 mesh coke or finer. rIhe heater 56 is maintained at a temperature to heat the solid particles to a temperature of :about 1000 F. to 1400 I".

jIot combustion gases pass overhead through a gassollds separating device such as a cyclone separator 66 ror removmg entrained solids from the combustion gases and returning them'to bed 58 via dip leg 68. The gases pass overhead-through line 72 and may be passed through a Waste heat boiler or the like to recover heat therefrom. The heated solids are withdrawn from the bottom heater 156 through a standpipe 7'4 having a control valve 76 and Ijllked 11p by a .gas such as steam introduced through line .78. The resulting suspension is passed through line 82 rand returned to the lower portion of the distillation zone 24 where ythe heated solids supply heat for distillation. .Excess coke particles are withdrawn from fluid bed 26 'through Withdrawal line 84. The amount of steam and .'gaSeS Passing upwardly through bed 26 in distillation ZOU@ 2/6 is selected so that the superficial velocity of the 'llpllowiing gasif-orm material is between about 0.5 to 2.5 Pfer sec. to .give the density of bed 26 above referred I The vaporous products of coking lealving the top of listillation zone 24 `and passing through line 34 are fracni'onated in fractionatng system 42 to separate la light -tnaction comprising gas and about 430 F. end point lgasoline withdrawn through line -86 which is .further treated vas desired ito recover gasoline. From the upper corti-on of `fractionator 42 through line 88 is recovered heating oil of about 430 to 650 F. boilin-g range and "lower down through line 92 is recovered a gas oil boiling between yabout 650 and 1000 which is suitable as a 'v stock 'for catalytic cracking. A bottoms fraction boiling above .about l000 F. is withdrawn from`fractiona'tor 42 f through line 94 and may be removed from the process through line 96 but is preferablyV recycled to eedline 10 ahead of preheater 12. The bottoms fraction contains coil heater 112 is provided with a pressure release valve 1526 to ash the products of coking so that vapors are released and pass upwardly out through outlet line 128 into tractionating system 132 similar to that above described' in connection with Fig. l. The distillation vessel 1t1i6 is maintained at a temperature of .about 900 to 1050 F. and under 1a pressure of about 0 to 25 lbs. per sq. in. gage. Vaporized and distilled products pass overhead through `line 128 but are preferably irst passed through -a gas-solids separating means such as a cyclone separator (not shown) to separate most ofthe entrained solids from Ithe outgoing vapors and gases.

The distillation vessel is heated by introducing air or oxygen through line 1'34 into the uid bed of coke l1=14 to Iburn some of the coke. The products o'f combustion pass out with the conversion products through outlet line 128. These combustion products dilute the" dry gas produced in the process; however, this slight degradation in the value of this fuel gas is oiset by the great economy of heating the uidized solids distillation-zone by the direct injection of oxidizing gas into themass of duidized coke. Excess coke in the form of finely divided solids is withdrawn from the dense bed '114 through line 136. Coke particles in heated condition are withdrawn trom the bottom portion `of distillation vessel 116 and passed through line 112 for admixture with the residual oil as -above described. Instead of using coke from vessel 1-16, coke particles from an external sourcemay be passed through line 112.

Bottoms withdrawn from fractionating vessel 132 are recycled through line 106 to feed line 102 but may be withdrawn from the process through line 138.

Referring now to Fig. 3 of the drawings, the reference character 152 designates a line for feeding residual oil together with steam or light petroleum oil diluent and added coke particles, if desired, to heating and coking coil 154 substantially completely submerged in the upper portion of a dense fludzed turbulent bed of coke particles 156 in distillation zone 158. vThe dense bed 156 A has a level indicated at 162 with a dilute or disperse phase 164 thereabove. The upper portion of coil 154 extends above the level 162 of the dense bed and is then directed downward with the outlet being provided with a spray or nozzle member 166 for spraying the products of coking onto the dense bed 156. The. outlet end of coil 154 is provided with a vpressure release valve 168 adjacent nozzle member 166. The .temperature and "pressure conditions in coil 154 are substantially the same asin the coking coil of Fig. 2. The distillation zone functions similarly to that described in Figs. 1 andV -2 in that coke particles are separated from distillable oilsand gases formed4 by a coking process.

:Steam is introduced into the lower portion of distillation vessel 158 throughline 172 to assistv in maintaining they particles in dense iluidized condition in distillation vessel `158 and to aid in vaporization of the coledproducts. Arranged and submerged in the lower portion of the fluidized solids bed 156 in distillation vess`e1`158 is a coil 17,4- for Supplying heat to the fluidized bed Vof soilds` 1 56 by burningfcoke particles or coke in the coil. Cokefcontaining particles are withdrawn from the lower portion of ther iluidized bed 156 through standpipe 176 providedwitha control valve 178. The Withdrawn coke-containing solids lare mixed with air or other oxygen containing gasV introduced through line 182 and the mixture or suspension, passed through line 184 and coil 174 so that thebfurningnmixture as it passes through coi1l174 gives. of heatwhich byindirect heat exchange is vtransfnred'to4 the luidized solids bed 156. The ilue gas"l or gases of combustion leave the coil 174 through line 186Yand mayhefpassed through a Waste heat boiler to recover heat therefrom. M

Excess coke may be withdrawn from the fluidized bed I156 yof solids via line 18.8. Vaporous and gaseous pr'oducts leave overhead through line 192k after having preferably passed through agas-.solids separating device and are introduced into a fractionating system or the like as described in` connection with Fig. 1 above.

Referring now toFig. 4 of the drawings, the residual oil feed is "iirstt distilled under a vacuum or subatmospheric pressure lto remove some of the vaporizable constituents therefrom;M andV the thus. treated residual oil is coked and then distilledundersubatmospheric pressure.

The residualoil which is of the type above described is` passed through. line 202 and preheater coil 204. where it is heated toa temperature within the range of about 400 to 750 As abovel described. steam may be added to the residual. oil and, also. coke particlesA as nuclei forthe coke formedmay be added. The` heated residualoillundena pressure of about. 10 to 100.*lbs.. per sq. in. gageis passedthrough valved` line 206.to.a.dis tillation tower.208 maintained under a; subatmospheric pressure of about 1` to 20 inches of. mercury absolute by attaching a, vacuumpump (not. shown). and condensing system (not shown) to outlet line 212 from distillation tower 208. t

Distillable vapors go overhead through line 212 and are condensed and form cracking stock for catalytic or thermal units. The unvaporized residual oil is Withdrawn from the bottom of tower 208 through line 214, passed through heating coil 216 by pump 218 under a pressure of about 250 to 3000 lbs. per sq. in. suiiicient to prevent vaporization of the oil and heated to a temperature of about 800 to 1000 F. The oil during coking is preferably maintained under the above conditions for about 5 to 60 minutes. Coke particles and steam or a light petroleum oil diluent may be added to line 214 by line 219 to prevent or minimize coking of the oil in coil 216. The products of coking are then passed through line 222 having a pressure reducing means 224 into iluidized coke distillation zone 226 having a dense fluidized highly turbulent bed 228 with a level indicated at 232 and dilute or disperse phase 234 thereabove. The outlet end of line 222 is provided with a nozzle or spray member 236 preferably directed downward so that the products of coking are sprayed or ashed in a downward direction onto the dense bed 228.

Vapors from the products of coking pass overhead through line 238 to distillation tower 208 to separate high boiling fractions and to remove any entrained solids and unvaporized liquids. Vapors from line 238 are introduced at a lower point than the residual oil feed introduced via line 206. so that. the latter may exertl a scrubbing action. upon the former. Inv this manner vaporization of the lighter fractions of the residual feed is aided while the heavier portions of `thevapors from line 238 are condensed and the entrainedr solids and unvaporized liquid particles are scrubbed out. Coke dis-1 tillation zone 226` is maintained under a subatmospheric pressure of about 1 to y20 inches of mercury absolute. Steam is supplied throughline 242 to fluid. bed 228 in the coke distillation zone tomaintain the bed in a dense fluidized highly turbulent condition and to aid in vaporie zation. The supercial velocity of the steam Apassing upwardly through the iluidized bed of solids 228 is between about 0.5 and 5.0 feet per second when the solid particles are of a size between about and 400 mesh or finer.

Heat is supplied to the coke distillation zone to maintain it at a temperature of between about 800 and l050 F. by burning coke particlesin a coil submerged in the bed 228.` Coke particles are Withdrawnfrom the bottom of the fluidized bed 228- and passed to standipe or barometric leg 244 provided at its lower-` end with a control valve 246 for controlling the rate of withdrawal of coke from the fluidized bed 228.` Air introduced through line 248- picks up the withdrawn coke or coke containing particles and forms a suspension which is passed through line 252 and through coill 254 submerged in the lower portion of thefluidized bed 228 in the distillation zone 226; In this way heatfrom the burning coke is supplied to the iluidized bed 228 by indirectrheat exchange. Thehot combustion gases leave coil 254 through 'outlet 1ine-256and may be passed through a waste heat boiler, if desired, to recover heat from the hotcombustion gases.

Excess coke may be withdrawn from Huidized bed 228 via line 258.

In all the above forms of the invention inert materials such as sand, pumice, kieselguhr, Carborundum, etc., but preferably nely, dividedpetroleum coke is used to form the lluidized bed in the distillation zone and' some inert Solids in finely divided form may be added in amounts lof l5 to 100 lbs. per barrelof' feed to keep the interior of the coil` or coking equipment clean of coke; During the coking operation coke is formedand excess coke in iinelydivided'form is'removed from the process.

The conversion ofthe residual-oil, reducedcrude, whole crude, etc., is substantially complete to coke, gas` and distillable oil before it enters the distillation zone where the gas oil is rapidly vaporized and leaves the distillation zone after only negligible contact time. Because the conversion of the heavy residual oil is substantially complete in the conversion coil or equipment, the use of a relatively high temperature in the fluidized bed distillation zone does not adversely affect the product quality. The fluidized bed distillation zone functions as a means for distilling the gas oil product from the coke and forms an excellent way of separating coke particles formed during the coking or conversion of the heavy residual oil from distillable gas oil.

A specific example will be given with reference to Fig. 1. A vacuum residuum derived from a mixture of West Texas and South American crude oils and having an API gravity of about 7.4; a Conradson carbon of about 20 wt. percent, a viscosity greater than 1000 seconds Saybolt Furol at 210 F., and an initial atmosphelic pressure boiling point above about 1050o F. is diluted with 106 volumes of naphtha boiling in the range of about 300 to 400 F. per 100 volumes of residuum. Seed coke having a particle size of 100 to 200 mesh is added in amounts of 55 lb. per barrel of mixed feed. The mixed feed containing seed coke is introduced into heater 12 and soaker 14 and heated to about 800 F. at about 2100 p. s. i. g. pressure. Turbulence is maintained in soaking zone 14 by means of mechanical agitation. The residence time of the oil in liquid phase in heater 12 and soaker 14 at temperatures above about 775 F. is

about 150 minutes. Under these conditions the residual' feed is substantially completely converted to coke and distillable 4products without fouling of the'vessel walls. The coked products from soaking Zone 14 are introduced into uid solids distillation zone 24 containing a bed of fluidized coke maintained at about 900 F. and 0 p. s. i. g. Steam amounting to about wt. percent of the oil feed is introduced into distillation zone 24 to maintain the coke in a fluidized condition and to aid in the distillation process. The coked oil feed rate to distillation zone 24 is about 5 weights per hour per weight of coke in zone 24. As the coked oil is sprayed onto the hot iluidized coke in zone 24 it is rapidly vaporized and removed overhead by line 34 without substantial further conversion in zone 24. The coke content of the coked oil entering zone 24 amounts to about 86 lbs. (including the 55 lb. of seed coke introduced with the feed) per barrel of residuum plus naphtha feed; this coke remains in zone 24 in a dry, finely divided form and becomes a part of the lluidized mass in this `Zone. rl`he distillate from zone 24 is introduced into a fractionator 42 and fractionated into gas, gasoline, heating oil, gas oil and bottoms. From each barrel of mixed residuum plus naphtha feed the following products are obtained from the distillation zone; (l) about 16.7 lbs. of dry gas, (2) about 24 gal. of gasoline cut boiling below about 430 F. (including the naphtha introduced in the feed as diluent), (3) about 4.8 gallons of heating oil boiling in the range of about 430 to 650 F., (4) about 7.5 gallons of gas oil boiling in the range of about 650 to 1000 F. suitable for catalytic cracking feed, and (5) about 1.5 gallons of higher boiling bottoms suitable for fuel oil or for recycling to the process.

What is claimed is:

1. A residual oil conversion process which comprises coking a residual oil in liquid phase in a coil and ydrum cokng zone at a coking temperature in the range of 750 to 950 F., a pressure in the range of 100 to 3000 p. s. i., and for a time in the range of 2 to 240 minutes while in admixture with to 100 lbs/bbl. of coke particles of a size in the range of 5 to 250 microns and in admixture with to 120 vol. percent of naphtha diluent boiling in the range within the limits of 250 to 500 F. to obtain coke, distillable oils and gas, ashing the total efuent from said coking zone directly into a distillation zone containing a dense turbulent bed of fluidized coke particles maintained at a temperature in the range of about'800"F. to 1050- F. and aepressurein the range of 0 to 25 p. s. i. gauge to obtain said distillable oils as vapors without substantial coking and relatively dry coke, said drycoke becoming a part of said dense turbulent fluidized bed, recovering said vapors overhead Afrom said distillation zone as product, circulating a portion of said dense turbulent bed to a fluid solids heating zone wherein the solids are heated by combustion, and returning heated solids to said distillation zone to supply heat thereto.

2. A process for the conversion ofheavy residual petroleum oils containing extremely high boiling constituents, which comprises heating residual oil in a suspensoid coking coil zone at a coking temperature of about 750 F. to 950 F. and a pressure of about 100 to 3000 lbs. per sq. in. in liquid phase for about 2 to 240 minutes to convert the residual oil substantially completely to coke, distillable oil and gas, passing the total products of coking `to a distillation zone containing a relatively dense bed of nely divided cokeparticles uidized by upflowing gases and maintained at a temperature of about 800 VF. to 1050 F. and a pressure of about 0 to 25 lbs. per sq. in. gauge so that the products of coking .are llashed and distillable oils are taken overhead without substantial further conversion while the coke particles are separated and collected in the dense fluidized bed.

3. A process according to claim 2 wherein the heating of the residual oil is carried-out in a coil submerged in said dense uidized bed in said distillation zone and heat is supplied to said dense fluidized bed by withdrawing a porton of the coke partclesfromsaid dense bed and burning the Withdrawn coke particles in a coil submerged in said dense iluidized bed in `said distillaton zone to supply heat thereto by indirect heat4 exchange.

References Cited in the le .ofthis patent UNITED STATES PATENTS 2,382,755 Tyson Aug. 14, 1945 2,388,055 Hemminger Oct. 30, 1945 2,436,938 Scharmann et al Mar. 2, 1948 2,447,149 Wier Aug. 17, 1948 2,471,104 Gohr May 24, 1949 2,485,315 Rex Oct. 18, 1949 2,527,575 Roetheli Oct. 31, 1950 2,557,748 Liedholm J-une 19, 1951 2,598,058 Hunter May 27, 1952 2,675,294 Keith Apr. 13, 1954

Claims (1)

1. A RESIDUAL OIL CONVERSION PROCESS WHICH COMPRISES COKING A RESIDUAL OIL IN LIQUID PHASE IN A COIL AND DRUM COKING ZONE AT A COKING TEMPERATURE IN THE RANGE OF 750* TO 950*F., A PRESSURE IN THE RANGE OF 100 TO 3000 P.S.I., AND FOR A TIME IN THE RANGE OF 2 TO 240 MINUTES WHILE IN ADMIXTURE WITH 15 TO 100 LBS./BBL. OF COKE PARTICLES OF A SIZE IN THE RANGE OF 5 TO 250 MICRONS AND IN ADMIXTURE WITH 20 TO 120 VOL. PERCENT OF NAPHTHA DILUENT BOILING IN THE RANGE WITHIN THE LIMITS OF 250* TO 500* F. TO OBTAIN COKE, DISTILLATE OILS AND GAS, FLASHING THE TOTAL EFFLUENT FROM SAID COKING ZONE DIRECTLY INTO A DISTILLATION ZONE CONTAINING A DENSE TURBULENT BED OF FLUIDIZED COKE

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