| 摘要 |
Methods of and apparatus for mining, transporting, cleaning, treating, and otherwise processing coal and other solids and for recovering liquid media used in such methods and apparatus. In the method, the coal is beneficiated to separate it from foreign matter mixed therewith by introducing the coal into a body of a parting liquid which is or contains a halogenated hydrocarbon and has a specific gravity intermediate that of the coal and foreign material so that the coal will rise toward the top of the body of liquid and the foreign material will sink toward the bottom thereof. Any halogenated hydrocarbon present in the parting liquid in the beneficiation step is 1,2-difluoroethane or a fluorochloro derivative of methane or ethane selected from the group consisting of 1-chloro-2,2,2-trifluoroethane, 1,1-dichloro-2,2,2-trifluoroethane, dichlorofluoromethane, 1-chloro-2-fluoroethane, 1,1,2-trichloro-1,2,2-trifluoroethane, 1,1dichloro-1,2,2,2-tetrafluroethane, and trichlorofluoromethane. The apparatus comprises a separator in which coal and foreign material can be separated by a parting liquid, conveyors in which parting liquid can drain from coal and foreign material discharged from said separator, dryers for separating additional parting liquid from the clean coal and the foreign material in the gaseous state, and a system for recovering the vaporized parting liquid and converting it to liquid form. |
