In the light of existing problems of the Coal Washery of Tunlan Mine, this paper makes feasibility analysis on the scheme of the transformation of coal washing techniques including the three products' dense-media technique, crude-coal's refuse discharging with moving screen and recovery and transformation of float fine coal's pressure filter.

A historical leap of research on three-product HM cyclone;

lower productivity and unreasonable product structure,it was converted to a process of three-product HM cyclone with un-pressurized feeding as proposed by Guohua Sc.

regarding to its cleaning process,power supply and distribution,control system,and economic and technical indices;this process employing only one un-pressurized fed three-product HM cyclone and one jet-aerating flotation machine as its main cleaning equipment;production practice gave such merits as low investment of plant construction,high selectivity of cleaning,low power consumption.

In view of failure to meet the product quality and market requirement by present cleaning process at Xin- ghua Coal Preparation Plant,a proposal of adopting large model three-product HM cyclone is rinse.

In view of failure to meet the product quality and market requirement by present cleaning process and aged equipment at Hengshan Coal Preparation Plant,given is a proposal of adopting large model three-product HM cyclone for fully utilizing the coal resources,meeting the quality variation of feed coal and quality requirement from market,and increasing clean coal yield and economic benefit.

This article introduces the application effect of 3GDMC1200/850A three-product dense medium cyclone in Wangfenggang Coal Preparation Plant through technical reform,which lift efficiency of separation and increase the economic benefit.

Then according to the equation, we can get the diameter of the first overflow orifice, and then we determined the diameter of the three most important mouths of three-product dense medium cyclone structure parameters.

The paper has introduced the handling capacity improvement of no-volt product heavy media cyclone,solution to clean coal product with dirt,decrease of medium lose,together with the separation efficiency of cyclone and problems existing in dressing technology.