A heavy-fluid coal-cleaning process in which a calcium chloride solution having a specific gravity of approx. 1.4 is used for the separation, which takes place in a cylindrical tank 6 to 10 ft (1.8 to 3 m) in diameter with a conical bottom, the total height being nearly 30 ft (9.1 m). The cleaned coal rises to the top where it is removed by a chain scraper and delivered to draining towers.