The problem of frequent slag-dropping troubles exist ever since the beginning of putting boiler into operation for supercritical 600 MW unit in Yangzhou Power plant

affecting seriously the normal operation of unit.On the basis of an approach to several main affecting factors of slagging in boilers

through combustion-adjusting tests of the boiler

such as changing the oxygen concentration

the flow rate of primary air

the open-degree of secondary air gate inside and outside the burner and the intensity of swirling flow

the secondary air gate inside and outside the over-fired air(OFA) and the intensity of swirling flow

the flow rate of OFA

the air distribution mode

the flow rate of central air

and the combination of coal pulverizers etc.

the influence of boiler operating condition and variation of parameters upon the concentration of NOx emission and the slagging tendency has been studied

and the optimal operation mode of boiler under condition of the existing equipments and coal sort being put forward.