| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for producing ashless coal which can decrease the flowability and expansibility of ashless coal.SOLUTION: A method for producing ashless coal comprises: a slurry preparation step; an extraction step; a separation step; an ashless coal obtaining step; and a by-product coal obtaining step. In the slurry preparation step, coal and a solvent are mixed to prepare slurry. In the extraction step, the obtained slurry is heated to extract coal components soluble in the solvent. Subsequently, in the separation step, the slurry obtained in the extraction step is separated into a solution in which the coal components soluble in the solvent are dissolved, and a solid-concentrated liquid in which coal components not soluble in the solvent are concentrated. In the ashless coal obtaining step, the solvent is evaporated and separated from the solution separated in the extraction step to obtain ashless coal and the surface of the ashless coal is oxidized. |
