US 2639982 A
Description (OCR text may contain errors)
May 26, 1953 J. c. KALBACH PRODUCTION oF FUEL GAS FROM cARBoNAcEoUs soLIns Filed Apri; 3o, 1949 Nwl ' INVENTOR. JoH C. /y Ach' B WWY Patented May 26, 1953 PRODUCTION OF FUEL GAS FROM CARBONACEOUS SOLIDS John C. Kalbach, New York, N. Y., assgnor to Hydrocarbon Research, Inc., New York, N. Y., a corporation of New Jersey Application April 30, 1949, Serial No. 90,645
(Cl. liii- 197) 6 Claims.
This invention relates to a process for the generation of gas of high heating value from solid carbonaceous material. cic aspects, it relates to the hydrogenation of coal in the presence of a hydrocarbon oil which is vaporized under reaction conditions to orm a fuel gas of high heating value. An important feature of the present invention is the method `of charging solid particles as a dispersion into a zone of elevated pressure.
The process of the present invention is especially useful as applied to the production of fuel gases from solid carbonaceous minerals. It is contemplated that the process will nd particular application to the gasification of coal and similar fuels containing volatilizable constituents. Various grades of coal may be treated including anthracite, bituminous coals and lignite.
Waste coals, such as slack coal and the like, are suitable for use in the present process. The process is also applicable to the treatment of oil shale.
An object of this invention is to provide an improved process for the .production of gas of high heating value from solid carbonaceous material.
Another object of this invention is to provide an improved process for the hydrogenation of solid carbonaceous material,
A further object is to provide an improved method for feeding solids to a fiuidized hydrogen ation system operating at a high pressure.
Still another object is to provide an improved method for forming a dispersion of solid particles in a vapor stream.
A further object of this invention is to provide an improved process for the treatment of coal and similar carbonaceous materials containing volatlizable constituents to produce a fuel gas of high heating value.
Other objects and advantages of this invention will be apparent from the following detailed description.
In accordance with this invention, solid carbonaceous material in particle form is admixed with a hydrocarbon oil to form a slurry. This slurry or suspension of coal in oil is pumped into a reaction Zone Where it is contacted with a hydrogen-rich gas under conditions of elevated temperature and pressure suitable for hydrogenr ation. The hydrocarbon liquid used for the preperation of the slurry is preferably derived from the solid carbonaceous material. The oil is vaporized and converted to the extent that a fluidized bedlof substantially dry solids v is maintained@ In one of its more spe-` in the reaction zone. Vaporization of oil within the hydrogenation reaction zone is effective as a means for controlling the temperature at which the hydrogenation reaction is conducted.
In one embodiment of the invention, the slurry is passed through a heating zone under elevated pressure wherein it is preheated without substantial vaporization and the resulting preheated slurry injected into the hydrogenation Zone. Unvaporized oil passing to the reaction zone is vaporized, aided by the exothermic heat of hydrogenation, and at the same time some of the oil may undergo destructive hydrogenation whereby it is converted to hydrocarbons of lower boiling point. In another embodiment of the present invention, substantially all of the oil is vaporized, forming a suspension of coal particles in oil vapor. l
The hydrogenation step is carried out under iluid bed reaction conditions, the hydrogen-rich gas and hydrocarbon oil vapors serving as the fiuidizing medium for the solid particles of carbona-ceous material. Volatile constituents associated with the solid carbonaceous material, as well as the carbonaceous material and oil, are hydrogenated in the hydrogenation reactor. The resulting product comprises a large proportion of gaseous constituents of high heating value. Normally liquid products may be recovered from the product Vgas stream and part or all recycled to the process as the oil for preparation of the slurry. A solid residue or char is produced in the hydrogenation reaction whi-ch is suitable for use as a fuel, production of briduettes, production of4 hydrogen-containing gas, as by reaction with oxygen and steam, etc. The hydrogen for the hydrogenation reaction may be produced by gasification of the char with steam or a mixture of oxygen and steam, as is known in the art. The present process produces fuel gases of high heating value.
About equal parts of oil and carbonaceous solid by weight form a fluid slurry. Larger amounts of oil may be used if desired. The slurry may be readily pumped with conventional equipment and passed through pipe lines into the hydrogenation reactor. The slurry may be sprayed into the stream of hydrogen-rich gas entering the reactor.
,The size of the parti-cles used in making up the slurry is subject to considerable variation. The particles may range in size, for example, from a powder to particles of 1/4" in average diameter. The smaller particlesizes are advantageous in that they facilitate handling and increase the rate of hydrogenation.
The slurry is preferably preheated before introduction into the reactor. This may be effectively accomplished by passing it through a pipe heater of conventional design. Part or all of the hydrocarbon oil may be vaporized in the heater. The temperature Iat the outlet of the vheater should generally Abe `approximately` the temperature at which the reaction is carried out. Thus, the temperature may vary from about 550 tc about 1000 F. for the hydrogenation of coal. The heater should generally be opperated at a pressure at least the same as or higher than the pressure at which the reaction is carried out. The reaction pressure may range frein `about. 750
to 1000 pounds per square inch vgauge or' higher.
It is not necessary to use pure hydrogen for the reaction. A mixture of hydrogenand carbon oxides, such as lmay be readily obtained ,hy the gasification of carbonaceous solids withisteain or a mixture of oxygen and steam is suitable lor they present" process." Preferably ythe*hydregen cntent of the' lhy'drogen-co'I it'ainn'gV gass Ain excessY of G percehtbyvclume.' In m'ost applications of the prcessdisclosed herein-',"it-iscohtempiateii that 'the'char lor residue frqijn the drogenation reaction will be reacted with -a'mixture of steam and oxygen to produce a' hydrogenrich g'as 'which may be` fedf'dirctly`tothe hydrogenation Zone;
` Morev or less cracking of the hydrocarbon oil may take" place within'the heating zone.' `At thc same time, somel ofl the" yolatilizable constituents oi" the solid'carbonaceous material may be' released. 'The amun't'of cracking :of hydrocarbons and distillationcf'fthefcoalinay be controlled bl controlling the temperaure and Contact time of the'fslurr'yinthe'heatiig step."
-A hydrogenation catalyst is 'preferably used to accelerate 'th'hydicgnation reaction.' Various" imetals and* metal compzuri'dsy suitable as hydrogenation'`vcatalysts;`A as' V,forv example', nickelfhicll sulfide, oxalate iron'sulee; 'ne @aarsspiefeaav their@ te slurry prir to passing the mixture through the preheater. Hyclr'cgeri f'l's'" be' added Ato the simplicit aangetaste@ The 4igureisa diagrammatic: elevational View illustrating v'preferred methci f" i?l1,frY ,1g` out tiieprccsfs f'uisiritetitnl' For simiiity in the til'ed elfptiOn-f a rrie'frredmot 0f operation of tli'eprocess, (to follbw, caly is' 'used an example of thesolid arbonac'ccus material.
other and efbaaeais'iffa subst- With feiertage t@ the drawing.. @al f .Saibable partitie Size isjharseethr aan .lips l te. a feed besser .flolriiflicli it befed'in 'resuletled mamita-flte eh, va v 3.1.1 te @meer 4- 01` is Sipg'ied igt-he meer' @rves lief A suitable cataly'st',y such asniclxel 'sldefmlay be interlaced t0, the mixer ihrqush ,lge @y suitably, 11i the 'fQr ef e 'Paste'erf Slrfv *with The mixer 4 is provided with a suitable stirring mechanisn I for the preparation cf as/bstantially uniform slurry of coal particles inthe'il.v The'slurry producedwin the mixer'lis withdrawn thrughlineftoa pump 9l Where it is subjected'to increased pressureI and discharged thr'ough'line lI'I'to "a'prehea'ter I2 which risv of conventional design with""the slurry passing through externally heated pipes. Part y'of the slurry may be passed'through't'lie preheater and part "of 'the slurry passed-through line` I3,"or all of theslurry may be' passd'throu'gh' either, as determined by control valves I4 and I5.
erally, it is desirable to pass at least a portion of the slurry through the preheater I2. The slurry, under elevated pressure, is admitted to the hydrogenation reactor I'I through line I 8 into admixture with hydrogen-rich gas supplied to the hydrogenation Azone through line I 9. The heat ,supplied't/o the hydrogenatlon 'reaction l,zone by lines I 8 and 'Ilf'togetherwith the 'exothermic fenergy of the hydrogenation reaction, insures substantially complete vaporization of the oil in the slurry. yaporization of the oil may be acwcompli-shed in'the preheater in which case the hydrogen-,rich gas entering through line I9 need siippljf'A r1i5'f;"`of the heat requirements. Qn the the slurry may be supplied to lzone with substantially all of the oil in liquid phase whereupon sufficient heat is required from the hydrogen-rich gas stream supplemented by the heat of reaction to vaporize the oil in the hydrogenation zone. In this event. tu@ slueifyimayfbe sprsyegfdirlcuy into the nulazed Ibedfin the 'hydrogenatlcn sone-or int'o the hydrogen-.rich 'gas stream Yflowing'into the fluidized bed.' In any event, the hydrogen-'rich gas and vthe resultant foil vapors' v.pass upwardly through the "hydrogenation zone vin contact with alilu-idized bed' cf'f-soli'd carb'onaceous' material, thev vapors and gaspividing theluidi'zing mediurnfor agitation-oflthe'lbed of particles. Part of the oil may react -With hydrogen yor otherwise be converted 'to 'gaseous productsduring the process and some' `oil mayprc'ducedas'a result of hydroger'i'ation'.'` The 'oil 'vapors' are discharged from `the hydrogenation zone with the'product gas through linle2-I. Solid" residue or char re- 'su-lting from 'the hydrogenation is discharged fronithe reactor througlline 22 'as controlled by valve 23K. 'This char may contain 'a considerable quantity of 'carbon' and is 'suitable for use' as fuel or' for thegeneratidn'of'water gas, synthesis gas or the like by' reaction 'with -oxygen and steam.
The pressure at which the hydrogenation 4zone is operated'is 'co'trolled by4 valve 25. The pressureand temperaturevdthin the reactor are generally keptwithin'the range o'f from'about 750 to about 1000 pounds per square inch gauge :and 000 `t`o"900F." The 'oil ls' recovered from the product 'gas stream Iby a're'covery unit 26. Product gases are dischargedithrough line 24 as a fuel gas of `high fheating valuewhile the oil is recycled through line 2'I to a, mixer 4. Excess oil produced' by Vthe' process may be discharged from the'system through line 28. Oil from any outsidesource'may"be"supplied to the process through line 29. The amount 'of oil produced or consumed in' the hydrogenation reactor is a function -of the Vtemperature and pressure' at which the "reaction is' carried out. The quantity of liquid'produc'e'd may be"co`ntrolled bycontrolling the pressure and temperature and a balance 'may be' reached whereby there is no net oil production or loss in the process and the process is self-sucient. The quantity of oil recovered from the operation mayk be increased bydecreasing the operating temperature or by increasing the operating pressure and may be decreased'by" increasing the temperature or by decreasing the pressure:
An"especially important application of the process' of this' invention" is the production of fuel gases from solid carbonaceous materials, such as coal, by'hydrgenation at elevated pressure's where hydrocarbon oils are 'not readily availableand are not desired as products.` In suclia case, by'means of the prsent process all of the oils derived from the coal are converted to gases simultaneously with conversion of the coal. Sufficient oil is recycled within the system to form a slurry of the coal feed with the quantity of process oil controlled as described hereinabove.
Obviously many modications and variations of the invention, as hereinabove set forth, may be made without departing from the spirit and scope thereof and, therefore, only such limitations should be imposed as are indicated in the appended claims.
1. In a process for the hydrogenation of a solid carbonaceous material Iat an elevated temperature and pressure, the improvement which comprises forming a slurry of said solid carbonaceous material in particle form with a liquid hydrocarbon which is substantially completely vaporizable under reaction conditions, passing said slurry into admixture with a hydrogen-rich gas in a hydrogenation zone, vaporizing said liquid hydrocarbon within said hydrogenation Zone, maintaining a dense-phase fluidized bed of said carbonaceous material in said hydrogenation zone, passing said hydrocarbon vapors and hydrogenrich gas upwardly through said bed thereby effecting fluidization and reaction of said carbonaceous material with hydrogen, and recovering from the reaction zone the products of hydrogenation and vaporized liquid hydrocarbon.
2. A process as defined in claim 1 wherein the hydrogenation reaction is carried out at a pressure within the range of from about 750 to about 1,000 pounds per square inch gauge and at a temperature Within the range of from about 600 F. to about 900 F.
3. A process as defined in claim 2 wherein said solid carbonaceous material is coal.
4. A process as dened in claim l wherein a hydrogenation catalyst is admixed with said slurry.
5. In a process for the production of a fuel gas of high heating value, the improvement which comprises admixing coal in particle form with a vaporizable liquid hydrocarbon to form a slurry, passing said slurry through a heating Zone Wherein a substantial portion of the hydrocarbon is vaporized, passing said coal particles dispersed in hydrocarbon vapors into a reaction zone into admixture with a hydrogen-rich gas at a temperature Within the range or from about 600 F. to about 900 F. and at a pressure within the range of from about r750 to 1,000 pounds per square inch gauge, maintaining a dense-phase fludized bed of solid particles from said coal in said reaction zone, passing said hydrocarbon vapors and hydrogen-rich gas upwardly through said bed thereby effecting uidization thereof and reaction of said solid particles with hydrogen, discharging the resulting products of hydrogenation and hydrocarbon vapors from the reaction zone, and separating normally liquid hydrocarbons from normally gaseous hydrocarbons to produce said fuel gas.
6. In a process for the production of a fuel gas of high heating value from a solid carbonaceous material containing volatilizable constituents by hydrogenation of said solid carbonaceous material at an elevated temperature and pressure, the improvement which comprises forming a slurry of said carbonaceous material in particle form with liquid hydrocarbons, passing said slurry into admixture With a hydrogen-rich gas in a reaction zone maintained at an elevated temperature and pressure such that said carbonacecus material is hydrogenated, maintaining a dense-phase luidized bed of said carbonaceous material undergoing reaction Within said reaction Zone, eiecting vaporization of said liquid hydrocarbons within said reaction zone, passing the hydrocarbon vapors and hydrogen-rich gas upwardly through said bed to eiIect uidization thereof and reaction of said carbonaceous ma terial with hydrogen, discharging from the reaction zone the products of hydrogenation and vaporization comprising normally gaseous and normally liquid hydrocarbons, separating normally liquid hydrocarbons from the normally gaseous hydrocarbons discharged from said reaction Zone to produce said fuel gas, forming additional slurry of car-bonaceous material with said normally liquid hydrocarbons, and maintaining the pressure and temperature Within said, reaction zone such that the quantity of liquid hydrocarbons recovered therefrom is just suiiicient for the preparation of slurry feed to said reaction zone.
JOHN C. KALBACH.
References Cited in the le of this patent UNITED STATES PATENTS Number Name Date 1,342,790 Bergius June 8, 1920 1,996,009 Krauch et al. Mar. 26, 1935 2,414,586 Egloi Jan. 21, 1947 2,438,439 Hemminger Mar. 23, 1948 FOREIGN PATENTS Number Country Date 503,183 Great Britain Apr. 3, 1939 OTHER REFERENCES Meade: Modern Gasworks Practice, 2nd edition, page 384.