330 MW CFB锅炉落煤管和二次风管的改造及应用

Modification and Application of Coal Drop Tube and Secondary Air Cuct in 330 MW CFB Boiler

某循环流化床(CFB)锅炉的问题主要表现为落煤管磨损严重、漏煤现象频繁,给煤口及密封盒烧损变形严重,炉内温度场分布不合理,环保耗材用量大,飞灰含碳量大,2021年电厂对2号炉锅炉本体实施了改造,主要措施有改变落煤管型式,提升落煤管材质等级,提高给煤口高度;将原有的油枪风管部分封堵,下二次风口上移至和原上二次风口同样标高。改造后结果表明,满负荷时床温最高点降低10℃,整体床温分布均匀,环保耗材用量减少13%~24%。研究成果可在同类型CFB锅炉上推广。

The problems of a circulating fluidised bed(CFB)boiler are:serious wear of the coal drop tube and frequent coal leakage;serious burnt and deformed coal feed opening and sealing box;irrational distribution of the temperature field in the furnace;large amount of environmental protection consumables and high carbon content of fly ash.2021,the power plant implemented the modification of the boiler body of furnace No.2,and the main measures are to change the type of the coal drop tube,to improve the material grade of the drop tube,to increase the height of the coal feed opening,;to modify the original oil gun duct and secondary air duct;and to improve the height of the oil gun air duct.The main measures include changing the type of coal drop pipe,upgrading the material grade of coal drop pipe,increasing the height of coal feeding port;partially blocking the original oil gun duct,and moving the lower secondary air outlet to the same elevation as the original upper secondary air outlet.The results of the modification show that:the highest point of bed temperature at full load is reduced by 1o C,the overall bed temperature distribution is even,and the amount of environmental protection consumables is reduced by 13%~24%.The research results can be promoted in the same type of CFB boiler.