Process for Production of Low Ash Clean Coal from High Ash Coal with Total Solvent Recovery

摘要

A process to produce low ash clean coal from high ash coal with substantially complete solvent recovery, the process including: forming a slurry of coal fines in a N-Methyl-2-pyrrolidone (NMP) and Ethylenediamine (EDA) solution; maintaining said slurry in a reactor at a temperature range of 100° C. to 240° C. and a pressure range of 1 to 4 gauge (kg/cm2) for a period of about 15 minutes to 4 hours; separating the produced sample withdrawn from the reactor, one part being a filtrate and the other a reject; feeding the filtrate into an evaporator to recover 80-85% solvent; precipitating the concentrated filtrate material in an anti-solvent tank to separate coal from solvent; separating the coal by filtration, said separated coal having a reduced ash content; feeding the anti-solvent and solvent mixture into a distillation column to separate remaining solvent from the anti-solvent for reuse in the process.