Abstract: A process for converting coal to liquid hydrocarbonaceous products involving a liquefaction reaction in the presence of a coal derived recycle slurry and a non-coal derived solvent comprising a hydrocarbonaceous oil or distillation bottom residue thereof intrinsically contaminated with greater than 300 ppm total of vanadium and nickel. The liquefaction reaction is performed under hydrogen pressure (approximately 500-4000 psi) and under elevated temperature (approximately 300.degree.-500.degree. C.) using a weight ratio of non-coal derived solvent to coal of about 1/1 or less. The conversion of coal to liquids is greatly enhanced by the use of such a non-coal derived solvent under these conditions.

Abstract: Pyrite addition to a coal liquefaction process (22, 26) is controlled (118) in inverse proportion to the calcium content of the feed coal to maximize the C.sub.5 --900.degree. F. (482.degree. C.) liquid yield per unit weight of pyrite added (110). The pyrite addition is controlled in this manner so as to minimize the amount of pyrite used and thus reduce pyrite contribution to the slurry pumping load and disposal problems connected with pyrite produced slag.

Abstract: Conversion of raw coal to distillate liquid and gaseous hydrocarbon products by solvent liquefaction in the presence of molecular hydrogen employing recycle of mineral residue is commonly performed at a higher thermal efficiency than conversion of coal to pipeline gas in a gasification process employing partial oxidation and methanation reactions. The prior art has disclosed a combination coal liquefaction-gasification plant employing recycle of mineral residue to the liquefaction zone wherein all the normally solid dissolved coal not converted to liquid or gaseous products in the liquefaction zone is passed to a gasification zone for conversion to hydrogen. In the prior art plant the amount of normally solid dissolved coal passed to the gasification zone is just sufficient to enable the gasification zone to produce the entire process hydrogen requirement.

Abstract: In a coal liquefaction process the yield of liquid coal is increased with a concomitant decrease in the yield of normally solid dissolved coal by recycle of a product slurry containing mineral residue. In an integrated coal liquefaction-gasification process employing product slurry recycle wherein the net yield of normally solid dissolved coal from the liquefaction zone comprises the entire hydrocarbonaceous feed to the gasification zone, a moderate net yield of normally solid dissolved coal is conducive to an optimized efficiency for the integrated process. However, it is frequently difficult to perform the process at slurry recycle rates which are sufficiently low to be economically practicable because of a pumpability constraint on the solids level in the feed coal mixing vessel.

Abstract: In a coal liquefaction process including recycle to the liquefaction zone of a product slurry containing mineral residue, the minimum slurry recycle rate is determined by a pumpability constraint on the solids level of the slurry contained in the feed coal mixing vessel. If the solids level in the feed coal mixing vessel rises above the constraint level, the slurry recycle rate must increase. For coals which generate a high mineral residue content, adequate dilution of the slurry in the feed coal mixing vessel requires the slurry recycle rate to rise to an economically impracticable level. To avoid a high recycle rate the catalytic advantage of recycle solids is increased by reducing the median diameter of the particles in the recycle slurry stream by passing a portion of the product slurry through a hydroclone to produce a second recycle slurry comprising hydroclone overflow.

Abstract: In a coal liquefaction process including recycle of a product slurry comprising normally solid dissolved coal and mineral residue, the minimum slurry recycle rate is determined by a pumpability constraint on the solids level of the slurry contained in the feed coal mixing vessel. If the solids level in the feed coal mixing vessel rises above the constraint level, the slurry recycle rate must increase. For coals which generate a high mineral residue content, adequate dilution of the slurry in the feed coal mixing vessel requires the slurry recycle rate to rise to an economically impracticable level. In the present process, mechanical operability is improved and enhanced conversion of normally solid dissolved coal is achieved at a given constraint solids level by passing a portion of the liquefaction zone product slurry through a hydroclone with the hydroclone overflow stream constituting a second recycle slurry.

Abstract: In a coal liquefaction process which includes a recycle of a product slurry which contain recycle mineral residue and recycle of extraneous catalytic material to said liquefication zone, hydrocracking of the hydrocarbonaceous material from the mineral residue occurs and a mixture of hydrocarbon gases, dissolved liquid, normally solid dissolved coal, suspended mineral residue and suspended extraneous catalytic mineral results. A first portion of said residue slurry is recycled to the liquefication zone, a second portion is passed to separation means and the third portion goes to a hydroclone. Overflow from the hydroclone goes to the liquefaction zone to reduce the median diameter of the particles recycled.

Abstract: A combination coal liquefaction-gasification-naphtha reforming process wherein the slurry containing substantially the entire yield of normally solid dissolved coal produced in the liquefaction zone comprises substantially the only hydrocarbonaceous feed for the gasification zone and wherein a portion of the naphtha produced in the liquefaction zone is passed through the reforming zone for conversion to gasoline with the remainder of the naphtha being burned as fuel within the process. The amount of hydrocarbonaceous material charged to the gasification zone is established so that the thermal efficiency of the process is substantially unaffected by changes in the ratio of naphtha passed through the reforming zone to naphtha burned as process fuel. The thermal efficiency of the process is maintained at a high level regardless of minor variations in normally solid dissolved coal yield by changing the ratio of naphtha passed through the reforming zone to naphtha burned as process fuel.

Abstract: An integrated coal liquefaction-gasification-naphtha reforming process wherein the slurry containing substantially the entire yield of normally solid dissolved coal produced in the liquefaction zone constitutes the only hydrocarbonaceous feed for the gasification zone and wherein substantially all of the naphtha fraction produced in the liquefaction zone is passed through the reforming zone for conversion to gasoline. The cost in terms of thermal efficiency for performing the reforming step is very low when the amount of syngas produced in the gasification zone is adequate to provide upon direct combustion a considerable proportion of the fuel requirements of both the liquefaction and reformer zones.

Abstract: This invention relates to a combination coal liquefaction-gasification process wherein hydrocarbonaceous mineral residue-containing slurry from the liquefaction zone is recycled to the liquefaction zone and all non-recycled hydrocarbonaceous mineral residue-containing slurry is passed to a gasification zone for conversion to synthesis gas to supply hydrogen for the liquefaction zone. It has now been discovered that in this process a surprisingly high reaction selectivity in favor of the desired distillate oil product is achieved by combining low liquefaction zone residence times and relatively high rates of recycle of mineral residue-containing slurry compared to feed coal rate. Under these conditions the yield of the desired distillate oil product can be increased to an unexpectedly high level while the yields of both higher and lower boiling products are each being decreased and while hydrogen consumption is being reduced.

Abstract: A process for liquefying coal involving heating only a portion of a the total process hydrogen stream to increase its temperature to a relatively high level and admixing said heated hydrogen with only a portion of the total coal slurry in the upstream region of a dissolver zone. The hydrogen stream has a relatively low specific heat and the addition thereto of a relatively small amount of heat increases its temperature to a level which is sufficiently high to initiate hydrocracking reactions when the hot hydrogen stream is intermixed with only a portion of the dissolver feed slurry, provided that the dissolver feed slurry contains recycle mineral residue in an amount adequate to catalyze hydrocracking reactions. Because the recycle mineral residue catalyzes the exothermic hydrocracking reactions, sufficient process heat is generated to permit addition to the dissolver zone in a downstream region thereof the remainder of dissolver feed slurry and process hydrogen in a relatively cool condition.

Abstract: A coal liquefaction process wherein a feed coal-solvent slurry is preheated in a thoroughly back-mixed preheater zone and then passed to a dissolver zone. Hot hydrogen is introduced to the process downstream from the preheater zone at or in advance of the dissolver zone and exothermic hydrocracking reactions occur in the dissolver zone. A dissolver zone effluent stream is passed through a vapor-liquid separator and separated hot dissolver vapor at process pressure is vented through the preheater zone wherein it is quenched to provide direct transfer to the preheater zone of the exothermic heat generated in the dissolver zone. The preheater zone is continuously vented to provide rapid removal of cooled vapor from the preheater zone and from the process, advantageously leaving an accumulation of liquid in the preheater zone boiling between the temperatures of the vapor-liquid separator and the preheater zone at process pressure.

Abstract: Conversion of raw coal to distillate liquid and gaseous hydrocarbon products by solvent liquefaction in the presence of molecular hydrogen employing recycle of mineral residue is commonly performed at a higher thermal efficiency than conversion of coal to pipeline gas in a gasification process employing partial oxidation and methanation reactions. The prior art has disclosed a combination coal liquefaction-gasification process employing recycle of mineral residue in the liquefaction zone wherein all the normally solid dissolved coal produced in the liquefaction zone is passed to a gasification zone for conversion to hydrogen, where the amount of normally solid dissolved coal prepared and passed to the gasification zone is just sufficient to enable the gasification zone to produce the exact hydrogen requirement of the process.

Abstract: Conversion of raw coal to distillate liquid and gaseous hydrocarbon products by solvent liquefaction in the presence of molecular hydrogen employing recycle of mineral residue is commonly performed at a higher thermal efficiency than conversion of coal to pipeline gas in a gasification process employing partial oxidation and methanation reactions. The prior art has disclosed a combination coal liquefaction-gasification process employing recycle of mineral residue to the liquefaction zone wherein all the normally solid dissolved coal produced in the liquefaction zone is passed to a gasification zone for conversion to hydrogen, where the amount of normally solid dissolved coal passed to the gasification zone is just sufficient to enable the gasification zone to produce the process hydrogen requirement.

Abstract: Conversion of raw coal to distillate liquid and gaseous hydrocarbon products by solvent liquefaction in the presence of molecular hydrogen employing recycle of mineral residue is commonly performed at a higher thermal efficiency than conversion of coal to pipeline gas in a gasification process employing partial oxidation and methanation reactions. The prior art has disclosed a combination coal liquefaction-gasification process employing recycle of mineral residue to the liquefaction zone wherein all the normally solid dissolved coal not converted to liquid or gaseous products in the liquefaction zone is passed to a gasification zone for conversion to hydrogen, where the amount of normally solid dissolved coal passed to the gasification zone is just sufficient to enable the gasification zone to produce the process hydrogen requirement.