Abstract:When a boiler is burning a kind of coal with slagging tendency like Shenhua coal,slagging problem of water wall will happen if it is suffering continuous slow load.The main reason is that great reduction of flue grass temperature can lead to much lower temperature of combustion and primary air,which reduces drying capability of coal pulverizing system and combustion condition of furnace.As pulverized coal without sufficiently drying coming into furnace,it postpones ignition and reduces the burning rate.As a result,some large size burning particles tend to hit and stick to water wall and cause slagging.The generalized regenerative technology is introduced that significantly improves the temperature of combustion and primary air under low load,which fundamentally solves the problem of the water wall slagging under low load and improves the safety of the boiler.