Abstract: The invention disclosed relates to a method for drying low-quality solid carbonaceous fuels such as lignite and sub-bituminous coal to reduce the moisture content substantially to zero, and to minimize re-adsorption of moisture during storage and transporation. The method involves drying the solid fuel in a mildly reducing atmosphere at a temperature in the range of 150.degree.to 300.degree. C., preferably 200.degree.to 210.degree. C. The mildly reducing atmosphere may be provided by a gaseous lower-alkane e.g. propane and methane. In some cases, the coal may beneficiated by agglomeration with small amounts of oil.

Abstract: An improved process is described for agglomerating ground coal in which a bridging oil is used as the agglomerating vehicle. This bridging oil is a mixture of a heavy gas oil obtained from coal/oil coprocessing and a heavy hydrocarbon oil, such as bitumen or heavy oil, preferably mixed in the proportion of about 23-40% heavy hydrocarbon oil and 60-77% heavy gas oil. The agglomerated product is mixed with additional heavy oil or bitumen and it becomes the feedstock to a coal/oil coprocessor, with heavy gas oil being formed as one of the product streams. At least part of this heavy gas oil product stream is recycled to the agglomeration stage as the heavy gas oil component of the bridging oil. This agglomeration procedure has the advantage of providing an agglomerate of excellent quality, while carrying out the agglomeration in a short time at ambient temperature and using less than 10% by weight of bridging oil.

Abstract: In the present invention, iron sulfate is added in the form of an aqueous wash solution to coal agglomerates after separation of ash from the agglomerated coal. As the agglomerates remain in a continuous water phase, a good dispersion of the iron sulfate solution throughout the agglomerate matrix occurs. At this stage an unexpectedly strong adsorption of Fe ions onto the coal surfaces occurs without any adverse effects on agglomerate integrity and the ability to separate it selectively by floatation. Furthermore, this good dispersion also results in over 94% of the iron sulfate in the wash solution being transferred to the agglomerates. This manner of addition of iron sulphate to coal has been shown to elevate advantageously the lowest temperature at which coke formation occurs during coprocessing.

Abstract: Carbonaceous components are separated from particulate coal containing inorganic solids by agitating and aerating the coal, agglomerating oil and water to form agglomerates of carbonaceous components of the coal and oil with air trapped in the agglomerates. The air trapped in the agglomerates makes them buoyant so that they collect at the surface of the water, for easy removal, while inorganic residual solids collect at the bottom of the water. The inorganic solids containing coal comprise previously formed agglomerates which are broken down by the agitation to form a slurry. In the latter case the process is for removal of inorganic solids which were not removed during the initial agglomeration. The agitation may be accomplished by a stirrer, impeller or a pump.

Abstract: Carbonaceous coal particles, essentially free of pyritic sulphur, are removed from an aqueous coal slurry in two steps. In the first step the carbonaceous particles of the slurry, with the pyritic sulphur essentially free of surface conditioning agent, are micro-agglomerated with agglomerating oil added in an amount varying from about 0.5 wt % (dry basis), when the coal particle average size is about 100 microns, to about 10 wt % (dry basis) when the average coal particle size is about 4 microns to remove relatively coarser particles of pyritic sulphur. Then, without adding any further agglomerating oil, relatively finer pyritic sulphur particles trapped with water in the micro-agglomerates are removed.

Abstract: Low-rank or oxidized coal is processed to produce fuel of relatively higher calorific value by conditioning a slurry of the coal with an electrolyte, and then agglomerating the carbonaceous portion of the coal using a coal derived agglomerating oil. Agglomerates may be first formed in a high shear mixer and then larger agglomerates formed in a low speed mixer. The agglomerates may be processed in a coal liquefaction plant and a portion of the coal derived oil produced in the plant used as the agglomerating oil.

Abstract: Persistent chemisorption bonds of clay solids in clay-containing heavy oil and water emulsions, from oil sands, heavy oil or conventional oil wells, are broken down by mixing the emulsion with an aqueous mixture of coal particles so that the mixture has a suspension density in the range 1 to 50 weight % solids. The coal particles have a particle size in the range 5 to 100 .mu.m so that occluded hydrophilic, inorganic solids are separable from a substantial portion of the hydrophobic, carbonaceous substances of the coal. The mixing of the emulsion with the aqueous suspension of coal particles is continued until agglomerates are formed comprising essentially carbonaceous components of the coal and the heavy oil thereby breaking down the chemisorption bonds by interdependantly dissociating carbonaceous components of the coal and heavy oil from the clay solids and other hydrophilic, inorganic solids and water from the coal and heavy oil.

Abstract: An aqueous phase continuous, fuel slurry is claimed, and its method of production from agglomerates consisting essentially of carbonaceous particles, agglomerating oil and residual water. The slurry may be formed by thoroughly mixing with agglomerates an agglomerate dispersing and coal/oil/water system interfacial tension reducing agent with the agglomerates so that the agglomerates are broken down and an aqueous phase continuous fuel slurry is formed containing residual, oil produced flocs from the agglomerates and having an oil content of the fuel slurry no greater than 10 weight % of the solids content of the fuel slurry. The solids content of the fuel slurry is in the range of the order of 50 weight % and of the order of 80 weight % of the total weight of the fuel slurry, and is preferably in the range of the order of 65 weight % to of the order of 70 weight %.

Abstract: A process for selectively removing hydrophilic constituents from flowable hydrophobic mixtures and suspensions which comprises forming a tenacious paste by mixing water with finely divided material which is insoluble or substantially insoluble in water and in the organic liquid in the hydrophobic mixture or suspension, which is inert to the organic liquid and the hydrophobic materials in the hydrophobic mixture or suspension and which is capable of selectively adsorbing said hydrophilic constituents. The paste is formed in a mixing-type liquid-liquid contactor so that a layer of the paste forms on and clings to the impellers and other internal surfaces of the contactor.

Abstract: An in-line method for the beneficiation of coal and the formation of a coal-in-oil combustible fuel wherein the coal is wet pulverized, micro-agglomerated with light oil to dissociate a large amount of inorganic impurities and some water, agglomerated with heavy oil to form relatively larger agglomerates and dissociate mainly water with some inorganic impurities, and then mixed with further heavy oil to form the coal-in-oil combustible fuel.

Abstract: The sulfide surfaces of finely-divided impure iron sulfide-containing minerals such as pyritic ores or coals are rendered hydrophilic by the adsorption of conditioned, inorganic sulfide-oxidizing bacteria. This adsorption of conditioned bacteria occurs in a short time to render the surfaces hydrophilic and allows these altered sulfide particles to be separated from hydrophobic solids by flotation, oil-agglomeration or the like. This bioadsorption process has particular applicability to pyritic coal beneficiation.