Abstract: The cleaned coarse slime is rather high in ash due to poor performance of the clean coal magnetic tailings classification-desliming system and high equipment failure rate. Through analysis of the magnetic tailings separation and recovery processes and equipment used, work is made on renovation of the magnetic tailings classification-desliming and ash reduction system by using the DZSN3028 3-mass high-frequency screen. Application of the renovated system has led to reduction of ash of clean coarse slime from 10.92% to 8.18% and a rise of yield of clean coal, and the plant′s heavy medium separation system is no longer required to reduce the ash of its clean coal product down to an unnecessarily low level.