低氧气氛下煤粉燃烧特性

为研究煤粉低氮燃烧时CO_2成分在低氧含量气氛下对燃烧的作用,在热重分析仪上进行了煤粉低氧气氛下的燃烧试验。通过模拟真实燃烧反应中的反应气氛,研究了O_2/CO_2混合比例、升温速率对煤粉燃烧特性的影响。结果表明,在O_2/CO_2混合气氛下,温度为1 000℃以内均存在着燃烧反应和气化反应的竞争关系。CO_2含量高时,CO_2与煤粉的气化反应对煤粉燃烧反应抑制程度逐渐增加。O_2/CO_2比例降低,煤粉的燃尽温度升高幅度明显,煤粉难以燃尽;煤粉的点火温度受CO_2含量影响不大;升温速率由10℃/min升至20℃/min对煤粉可燃性和着火稳定性提升明显,20℃/min升至30℃/min影响不大。

Combustion characteristic of pulverized coal in hypoxic atmosphere

In order to investigate the effect of CO2 component to combustion in the hypoxic atmosphere,while realizing low NOx combustion of pulverized coal,experiments of coal combustion in hypoxic atmosphere were conducted on thermogravimetric analyzer.To simulate the real reaction atmosphere,effects of different O2/CO2 mixing ratios and heating rates to the combustion characteristic were conducted.The results show that a competitive relation is found between combustion and gasification of coal in the O2/CO2 mixing atmosphere,when the reaction temperature is below 1 000 ℃C.Higher CO2 content will improve the restriction level of pulverized coal combustion by gasification reaction with coal.Lower O2/CO2 mixing ratio will restrain the burnout of coal,while the ignition temperature is hardly impacted by the CO2 content.A heating rate improvement of 10 ℃/min to 20 ℃/min will apparently enhance the ignition and combustion stability of coal,while improvement of 20 ℃/min to 30 ℃/min has no such influence.