Deashing process for coal

摘要

A process for reducing ash content of coal with an initial concentration of inherent ash of approximately 0.25 w/o to approximately 3 w/o. The coal is swollen and wetted with an alcohol solution such as methanol, then deashed with a mineral acid solution such as hydrochloric and hydrofluoric acid. The demineralized coal is neutralized, washed, and dried for use in making coal slurries with a very low ash content.