Abstract: Aiming at the problem of recovery rate of lump coal is low in Meihuajing branch of Ningdong coal preparation plant,adding a bypass chute into the feeding chute of lump coal sizing screen,and designed bypass chute,based on that carried out the optimization on the separation process. After the renovation and optimization,the clean coal recovery rate increased,and the power consumption and matcrial cost both reduced,obtained significant economic benefits.