2070t/h超临界对冲火焰锅炉飞灰含碳量偏高原因分析

针对湖南某电厂2 070t/h超临界对冲火焰锅炉燃用运行煤种出现的飞灰含碳量偏高的现象,对其锅炉进行了热态调整试验,研究了炉膛氧量、负荷、燃尽风量和煤粉细度的变化对飞灰含碳量的影响。研究结果表明,炉膛氧量、负荷、燃尽风量和煤粉细度的变化对飞灰含碳量有较大影响。负荷增加、煤粉细度减小,飞灰含碳量降低;燃尽风量和炉膛氧量过低或过高都会使飞灰含碳量升高,运行中炉膛氧量和燃尽风量存在一个最佳值;而且,燃尽风对飞灰含碳量的影响与负荷有关。依此对该锅炉运行进行优化调整,使飞灰含碳量降低到4.5%以下。

A cause analysis on high carbon content in fly ash of 2 070 t/h supercritical hedge flame boiler

In practical boiler operation of a Hunan power plant,fully blended coal would lead to high carbon content in fly ash.Focusing on this phenomenon,a series of thermal adj ust-ment experiments are conducted on furnace oxygen amount,loads,over-fired air,coal fine-ness.The results show that carbon content in fly ash is significantly affected by fluctuations of fore mentions：increasing loads and reducing coal fineness would decrease carbon content in fly ash,either excessive low or high of furnace oxygen amount and over-fired air would elevate carbon content in fly ash,thus both furnace oxygen amount and over-fired air have an optimal value respectively in operation;moreover,the interaction between over-fired air and carbon content in fly ash is related to loads.Operating the optimum regulation to the boiler based on the analysis,the carbon content of fly ash would be controlled under 4.5%.