KTK has three open-pit coal mines with a total annual output of 11 million tons. Among them, the coal mined by vinogravski open pit mine will be sent to kaskad 2 coal preparation plant for processing. Because of the low ash and sulfur content and high calorific value of coal, open-pit mining is suitable for power plant fuel. Kaskad 2 is the first coal preparation plant to combine the two enrichment methods into a complete production process. It adopts a large angle separator for coarse-grained pre screening and heavy medium separation, which can reduce the consumption of gangue from 50% to 12%, and adjust the ash content.