600MW燃煤机组锅炉排烟温度偏高的原因分析

Cause Analysis for High Exhaust Gas Temperature of 600 MW Unit

某电厂600 MW燃煤机组存在锅炉排烟温度比设计值明显偏高的现象,严重影响机组的经济运行。通过从环境温度、入炉煤煤质、锅炉结渣、空预器漏风状况及空预器传热性能方面分析,研究结果表明:环境温度偏高、入炉煤水分Mt增大、空预器传热性能较差(烟气侧传热效率及X比低于设计值)是排烟温度升高的主要原因,其中因空预器传热性能较差,A、B两侧排烟温度(进风温度修正后)分别因此升高了5.6℃与6.2℃.锅炉结渣及空预器漏风较轻,未对排烟温度造成明显影响。

The exhaust gas temperature was much higher than designed value in 600 MW unit in Tieting Power Plant, which seriously affects economic benefits. By analysis in environment temperature, coal quantity index of coal as fired, boiler slagging, air leakage situation of air pre-heater as well as heat transfer efficiency of air pre-heater, the results shows that the higher environment temperature, higher moisture of coal as fired and poor heat transfer efficiency of air pre-heater （the heat transfer efficiency in flue gas side and X ratio are higher than designed values） are the main reasons for high exhaust gas temperature. During to the poor heat transfer efficiency of air pre-heater, the exhaust gas temperature （environment temperature correction） in both A and B sides increased by 5.6 ℃ and 6.2 ℃. The boiler slagging and air leakage of air pre-heater were.slightly and had no effects on exhaust gas temperature.