1. A 44% yield of coking concentrate with 8% ash can be obtained by preparing Urgal coals with 32–33% ash by a combined system including centrifugal separation. Preparation of these coals by the use of hydrocyclones+flotation give a concentrate with>11% ash with yield 37%, or a concentrate with 9.3% and yield 23% based on run-of-mine coal. If the centrifugal concentrate's ash content is brought to the level of the product obtained in hydrocyclones, the yield is increased to 48%. 2. The use of centrifugal preparation eliminates the need for individual extraction of coal seams in the Urgal coal field; after preparation, the total output of a pit can be used for coking plants, the middlings being used for power plants.