| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for producing ashless coal including a step enabling separation of a solution containing a solvent-soluble coal component from a solid concentrated liquid without adding (mixing) a solvent to the solid concentrated liquid separated by gravitational sedimentation process.SOLUTION: A slurry obtained by an extraction step is separated, as a first separation step, by gravitational sedimentation process into a solution containing a solvent-soluble component and a solid concentrated liquid containing concentrated solvent-insoluble component. The solid concentrated liquid separated by the first separation step is separated, as a second separation step, by centrifugal separation process into a solution containing a solvent-soluble coal component and a solid concentrated liquid containing further concentrated solvent-insoluble coal component. |
