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US 4,304,573 AGranted
Process of beneficiating coal and product
AssigneeGulf & Western Industries, Inc.
InventorsLester E. Burgess, Karl M. Fox, Phillip E. McGarry
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AssigneeGulf & Western Industries, Inc.
InventorsLester E. Burgess, Karl M. Fox, Phillip E. McGarry
Estimating the term…
Mine run coal is pulverized and the extended surfaces of the coal particles are rendered hydrophobic and oilophilic by a chemical bonding and graft polymerization reaction with a water unsoluble organic polymerizable monomer under peroxidation influence in a predominantly water reaction medium. The mineral ash present in the coal and particularly the iron pyrites remains hydrophilic and is separated from the polymeric organic surface bonded coal product in a water washing step wherein the washed coal floats on and is recovered from the water phase and the ash is removed with the separated wash water in a critical wash step. The hydrophobic and oilophilic organic polymeric surface bonded coating about the coal particles is fortified by inclusion of additional unbound free fatty acids by further small additions thereof. Excess water is removed from the beneficiated hydrophobic surface-altered coal product mechanically, and the carboxylic acid groups present in the coal-oil product are thereafter converted to a metal soap. The beneficiated coal product can be used "dry", or additional quantities of a liquid hydrocarbon fuel can be incorporated with the "dry" beneficiated coal product to produce a flowable fluid or liquid coal product having the rheological property of marked thixotropy. Introduction of this physically induced property into the liquid coal-oil-mixture prevents settling out of the heavier coal particles from the relatively ash-free fluid fuel composition under extended storage periods.
A beneficiated particulate coal product comprising coal particles coated with surface treating amounts of a polymerized organic coating sufficient to render said coal particles both hydrophobic and oleophilic, said coal particles having been provided with said polymerized organic coating by contacting pulverized coal with a mixture comprised of a polymerizable monomer, a free radical catalyst, free radical initiator, a major amount of water and a minor amount of fuel oil and wherein said hydrophobic and oleophilic coal particles have been water washed.
A process of cleaning coal which comprises suspending pulverized coal in water, subjecting the surface of the pulverized coal in suspension in water to a graft polymerization step to render said coal both hydrophobic and oleophilic, said graft polymerization step comprising contacting said pulverized coal in suspension in water with a mixture comprising a polymerizable monomer, a free radical catalyst, a free radical initiator and a minor amount of a liquid hydrocarbon fuel oil, water washing said hydrophobic and oleophilic coal to remove select impurities, and mechanically extracting the water from said cleaned coal thereby reducing the water content thereof to levels less than about 15% by weight.
A process for beneficiating coal which comprises pulverizing a first coal-water slurry to a coal particle size of 48 mesh or greater in the presence of a free radical initiator comprising an active metal ion and a polymerizable unsaturated organic monomer thereby initiating graft polymerization and then completing the graft polymerization reaction by adding a free radical polymerization catalyst whereby said particles are surface coated with a polymer of said monomer to render said particles hydrophobic and oleophilic.
A coal beneficiation process which comprises slurrying coarse particulate coal in water to form a fluent aqueous suspension, subjecting said aqueous suspension to attrition and coal particle size reduction, introducing into said suspension, during or subsequent to completed attrition, coal particle surface treating amounts of a graft polymerizable unsaturated water insoluble monomer, a minor amount of a water insoluble organic liquid fuel, a free radical polymerization initiator comprising an active metal ion, and subjecting said coal particle surfaces to a chemical grafting reaction by treatment of said suspension with a peroxidation catalyst, thereby polymerizing said unsaturated monomer on the surfaces of the coal particles rendering said surfaces both hydrophobic and oleophilic, whereby said hydrophobic and oleophilic coal becomes intimately associated with the liquid fuel to form a coherent mass, which coherent mass separates and floats on the water phase of said suspension and whereby hydrophilic ash released from the coal during attrition and processing migrates into the continuous water phase;
A beneficiated pulverized coal -oil mixture having reduced sulfur and ash content comprising an intimate admixture of pulverized coal particles, the surfaces of which have been chemcially grafted with a polymerizable unsaturated monomer, a metal salt or soap of a water insoluble organic acid and an amount of fuel oil in excess of about 2%.
A coal beneficiation process which comprises slurrying coarse particulate coal in water to form a fluent aqueous suspension, subjecting said aqueous suspension to attrition and coal particle size reduction, introducing into said suspension, during or subsequent to completed attrition, coal particle surface treating amounts of a graft polymerizable unsaturated water insoluble monomer having the general structure ##STR6## wherein R is an aliphatic unsaturated hydrocarbon radical having at least about 8 carbon atoms, a minor amount of a water insoluble organic liquid fuel oil, a free radical polymerization initiator comprising a metal ion derived from a water soluble copper salt, and subjecting said coal particle surfaces to a chemical grafting reaction by treatment of said suspension with a peroxidation catalyst comprising hydrogen peroxide which polymerizes said unsaturated monomer on the surfaces of the coal particles rendering said surfaces both hydrophobic and oleophilic;
A beneficiated coal product of reduced sulfur content comprising coal particles, wherein the surfaces of said coal particles are coated with surface treating amounts of a hydrophobic and oleophilic polymerized organic coating sufficient to render said coal particles preferentially wetted by a hydrocarbon fuel oil phase, said coal particles having been provided with said polymerized organic coating by contacting pulverized coal with a mixture comprised of a polymerizable monomer, a free radical catalyst, free radical initiator, a major amount of water and a minor amount of fuel oil.
A process of beneficiating coal comprising pulverizing coal in an aqueous slurry in the presence of a minor amount of a liquid hydrocarbon fuel, the improvement which comprises including in said coal-water-oil slurry a polymerizable monomer and a metal ion graft polymerization catalyst initiator and reducing the particle size of said coal particles to 48 mesh or greater in said slurry and thereafter polymerizing said monomer about said reduced coal particles by addition to said pulverized coal slurry of a peroxidation catalyst.
A process for the beneficiation of coal by removal of ash comprising pulverizing coal in an aqueous slurry to a particle size of 48 mesh or greater, including in said water slurry a minor amount of a liquid hydrocarbon fuel, a polymerizable monomer, a metal graft polymerization ion catalyst initiator and a peroxidation catalyst thereby polymerizing said monomer about said pulverized coal particles to alter the surface of said particles to a hydrophobic and oleophilic quality.
A process for beneficiating coal which comprises mixing the coal in water and fuel oil, pulverizing the foregoing coal slurrry, chemically grafting a polymerizable monomer on the surfaces of the coal particles and separating the coal-oil phase from the water phase.
A beneficiated coal product of reduced ash content comprising pulverized coal particles the surfaces of said particles coated with a hydrophobic and oleophilic organic coating by chemical graft polymerization, said particles dispersed in a flowable hydrocarbon fuel.
A coal-oil mixture comprised of beneficiated pulverized coal particles, the surfaces of said coal particles coated with a hydrophobic and oleophilic organic coating prepared by contacting an aqueous slurry of pulverized coal particles with a mixture of a polymerizable monomer, a free radical catalyst, a free radical initiator and a minor amount of a liquid hydrocarbon fuel oil, said beneficiated pulverized coal particles dispersed in a liquid hydrocarbon fuel, said liquid hydrocarbon fuel being present in excess of 1% by weight of the total coal-oil mixture.
Dependencies are inferred from the claim text.