Abstract: The problems encountered by the plant during the course of carrying out commissioning and trial operation of washing systems include unsatisfactory coarse slime separation effect, blocking of water collection pipe under the middlings-refuse dewatering screen, and big noise of low-pressure air system in operation. Based on comprehensive analysis and investigations, corresponding measures are taken to deal with the situation. The measures adopted include adjustment of spiral separator′s feed density and pressure, optimization of layout of the funnel-formed drainage pipe beneath the middlings-refuse dewatering screen, renovation of piping of air system and addition of sound-damping material on compressed air receiver. The implementation of the targeted measures has led to shortening of commissioning time and smooth operation of the washing systems of the plant. The work made by the plant may serve as a valuable reference for design and construction of similar plants.