Selected from the coal refers to coal mining coal after washing out (selected from the application of the principles of gravity ore, coal water as a medium to be washing) and screening after processing, has been cleared or reduced ash contained in coal, gangue , sulfur and other impurities, and divided into several grades of coal according to different coal types, ash, calorific value and particle size. Coal having a particle size rating of 50, 25, 20, 13 and 6 mm or less. Washing coal can be divided into washing raw coal, washing coal, mixing coal, washing mixed coal, mixed coal, washing coal, coal, washing coal, pulverized coal and other varieties. The ash content of the washed coal is less than or equal to 32%, and the rest is required to be less than or equal to 40%. The coal preparation process can be divided into screening , physical coal preparation, chemical coal preparation, and bacterial desulfurization . Screening is the separation of coal into different particle sizes. At present, the widely used physical coal preparation methods include jigging, heavy medium and flotation . PREPARATION be physically removed more than 60% ash and 50% pyrite sulfur. Equipment of various coal variety, quality and meet the technical requirements of coal particle size, can improve the thermal efficiency and reliability, and significantly reduce the particulate matter and sulfur dioxide emissions. Therefore, coal preparation is not only the premise of rational coal use , but also the most economical way to reduce pollutant emissions from coal burning equipment . Swivel Clamp,Scaffolding Swivel Clamp,Scaffolding Clamp,Forged Swivel Clamp Hebei Qierjie New Energy Technology co., Ltd , https://www.qejfastener.com