超细煤焦的细度对再燃还原NO的影响

以烟煤和褐煤混煤超细煤粉制作的煤焦作为再燃燃料，用N2，O2，CO2，NO配制模拟烟气，在立式携带流反应器中进行了煤焦再燃还原NO的实验，研究了超细煤焦的细度对炉内1300℃高温烟气中再燃还原NO 的影响。结果表明：①NO 的还原效率随着超细煤焦细度的提高而增大；②在再燃燃料比为20%~25%、再燃区的初始氧浓度为2%~4%的工况范围内，煤焦细度对NO 还原效率的影响显著；③在其它情况相同的条件下，当煤焦细度由154mm筛下提高到71mm筛下时，再燃还原NO的效率增加幅度不大；当煤焦细度由71mm筛下提高到45mm筛下时，再燃还原NO的效率大幅度增加；④NO还原效率与煤焦粒径的2次方成反比。

Influence of the Micro-pulverized Coal Char Fineness on NO Reduction by Reburning

The experiment of the micronized coal char reducing NO was done in entrained flow reactor，N2, O2, CO2, NO was mixed into simulated flue gas and fuel was coal char made from micronized coal powder mixture of bituminous coal and lignite. The influence of fineness of micronized coal char on the reduction of NO in flue gas at 1300℃ was investigated. Experimental results show that① the reduction efficiency of NO increases with the decreasing of the particle size of coal char; ② the fineness of coal char has an important influence on the reduction efficiency of NO when reburning fuel ratio was 20%-25% and initial oxygen concentration was 2%-4% in reburning zone; ③when the size of coal char particle decreases from 154mm to 71mm, the reduction efficiency of NO does not increase greatly, while coal char particle decreases from 71mm to 45mm, the reduction efficiency of NO increase largely; ④the reduction efficiency of NO is inverse proportional to the square of coal char fineness.