465t/h循环流化床锅炉屏式再热器超温原因分析及改造

<title>erheating cause analysis and retrofitting of platen reheater of 465 t/h circulating fluidized bed boiler

通过对465t／h循环流化床锅炉再热器系统的流量分配、热偏差和吸热量的计算分析,发现原设计中屏式再热器系统进汽方式不合理引起的严重流量偏差是导致该型锅炉屏式再热器超温的主要原因,再热器整体吸热量偏大造成的汽温偏高和焓增过大进一步加剧了超温。经改进屏式再热器连接方式并减少受热面后,消除了屏式再热器超温,保证了机组安全运行。

<abstract>rough the calculation and analysis of the flow rate distribution, heat flux deviation and heat absorption of reheater system in 465 t/h circulating fluidized bed (CFB) boiler, it was concluded that serious flow rate deviation resulted from unreasonable connection mode was the main cause of platen reheater overheating. Bigger enthalpy increment and higher exit steam temperature of platen reheater caused by larger heat absorption further aggravated the overheating. Through improving the connection mode of platen reheater and decreasing the heating surface, the overheating of platen reheater was eliminated and the safe operation of unit was ensured.