IN2014KO00022A - - Google Patents

Abstract

The invention relates to an improved process to produce low ash clean coal from high ash coal involving 100% solvent recovery with 75% lower energy consumption, the process comprising: (i) forming a slurry of coal fines in organic solvent with a small amount of co-solvent; (ii) maintaining said slurry in a reactor at a temperature range between 100°C to 240°C and pressure range of 1 to 4 gauge (kg/cm2) for a period of about 15 minutes to 4 hours; (iii) separating the produced sample after withdrawal from the reactor, separation cut size being variable depending on the particle size to be treated including application of the end product, a first part of the separated sample being a filtrate or extract and the second part being a reject; (iv) drying the reject by a horizontal dryer, said separated reject having high ash content; (v) feeding the extracted part into an evaporator to recover the solvent; and (vi) feeding the concentrated material (bottom product of evaporator) into a vertical dryer to separate coal from the solvent, said separated coal having a reduced ash content.