Solvent recovery in a coal deashing process

摘要

An improved coal deashing process wherein coal is mixed with a first dissolving solvent, heated, solubilized and flashed to provide a prepared mixture. The flashing is effected at a temperature below about 650 DEG F. to increase the amount of the first dissolving solvent in the prepared mixture. The prepared mixture then is mixed with a second dissolving solvent to produce a feed mixture which is subjected to two or more successive phase separations. Insoluble coal products present are separated from the feed mixture in a first separation zone and the soluble coal products are recovered from the first and the second dissolving solvents in a second separation zone. The second dissolving solvent is recovered from the first and the second heavy fractions and the second light fraction for recycling to aid in producing the feed mixture. The first dissolving solvent is recovered from the first and second flash zones. This results in an enhanced recovery of the first dissolving solvent for recycle for utilization in the initial solubilization of the coal.