A test of grinding lignite using HP863 medium speed coal mill has been carried out

some major factors affecting the fineness of pulverized coal

such as the total moisture of lignite

the open degree of reflecting damper in the pulverized coal classifier

the gap of gringding roller

the primary air flow rate

and the output capacity of coal mill etc.

being studied.It is obtained from test that the fineness of pulverized coal is improved as increasing the open degree of reflecting damper in the pulverized coal classifier

but the fineness of pulverized coal is worsened as increasing the gap of grinding roller and the output capacity of the coal mill.The total moisture of lignite has great impact on the fineness of pulverized coal

and plays an important role on the output capacity of coal mill.The max.output capacity of HP863 medium speed coal mill can reach 34 t/h

and can grind high moisture lignite under condition of ensuring a dry output capacity.