锅炉低氮燃烧改造对煤灰熔融特性影响

Effect of low NOx combustion retrofit on coal ash fusion behavior of coal-fired boilers

为研究低氮燃烧改造对锅炉主燃区气氛以及对煤灰熔融特性的影响规律,首先对2台完成低氮燃烧改造的燃煤锅炉主燃区烟气成分进行测试,得出烟气成分分布范围;然后搭建一套气氛可调节的煤灰熔点测试系统,依据炉膛烟气成分测试结果,配制相应模拟气氛进行灰熔点测试,研究气氛变化对煤灰熔融特性的影响规律。结果表明:锅炉低氮燃烧改造后,主燃区CO体积分数由2%~3%上升至7%~15%,燃烧气氛由弱还原性气氛转变为强还原性气氛,煤灰熔点明显下降。

In order to study the efifects of low NOX combustion retrofit on the atmosphere in main combustion zone of the boiler and on the coal ash fusion behavior, the compositions of flue gas in main combustion zone of two coalfired boilers after low NOX combustion retrofit were tested and the flue gas composition distribution range was obtained. Then, an atmosphere-adjustable ash fusion test system was built up. The atmosphere of the ash fusion tests were prepared to simulate the combustion area flue gas atmosphere of ttie boilers studied・ The results show that, after the low NOx combustion retrofit, the volume fraction of CO in the main combustion area increased from 2%~3% to 7%~15%, the combustion atmosphere changed from weak reducing atmosphere to strong reducing atmosphere, and the ash fusion point decreased obviously.