Coal slime is a by-product in the process of washing and processing in coal preparation plant, and its main source is flotation tail coal which has many adverse factors such as fine particle size, high viscosity, high water holding capacity and low calorific value. The traditional treatment method is to stack the coal slime in the storage shed for direct sales after being filtered by the filter press, which is difficult to realize the industrial efficient and clean utilization. Reducing the moisture content of coal slime and realizing the high efficient and clean utilization have become an important topic of coal preparation technology research of Fengfeng Group. Through the research on low temperature drying technology of coal slime, the bottleneck problem that the coal slime can not be comprehensively utilized due to large moisture content was solved. After drying, the moisture content of coal slime is reduced to 14%, which improves the calorific value of coal slime, reduces environmental pollution, and achieves better economic and social benefits.