Ashless coal production method

Abstract

A method for producing an ashless coal includes an extraction step, a separation step and an ashless coal acquirement step. In the extraction step, a slurry obtained by mixing a coal with a solvent is heated and thereby a solvent-soluble component of the coal is extracted. In the separation step, the slurry is separated into a solution of the solvent-soluble component of the coal and a solid content-concentrated liquid. In the ashless coal acquirement step, an ashless coal is obtained by evaporating and separating the solvent from the solution. The solvent is a mixture of a dissolution medium and a coal extraction accelerator added thereto. The solvent contains a bicyclic aromatic compound that is liquid at ordinary temperature. The coal extraction accelerator containing no nitrogen has two benzene rings and has at least one cyclic structure having no double bond.

Dependencies are inferred from the claim text.