Experimental study on increasing the outlet temperature of HP983 coal mill was conducted on No.2 660 MW unit in a power plant.The concentration of CO

CO2 and O2 in variety of pulverized bituminous coal/air flows was investigated.Moreover

the operation performance of coal mill and boiler before and after the coal mill outlet temperature was enhanced were compared.The results showed that

increasing the outlet temperature of HP983 mill to 82 ℃ to 100 ℃ for pulverizing bituminous coal

and to 75 ℃ for pulverizing high volatile Indonesia coal

can ensure the safety operation of pulverizing system and the burner.With an increase in the mill outlet temperature

the fineness of pulverized coal and the NO emission will increase slightly

and the mill power will decrease obviously

so the economical efficiency of the unit operation will be enhanced.