采用两段反应器研究了三种煤在不同燃烧方式下抑制NOx生成的效果.结果表明,煤的热解气和部分气化生成气再燃均能较好的抑制NOx生成,抑制效果优于空气分级燃烧,解耦燃烧方式抑制NOx生成的效果最显著,相对于传统燃烧其NOx排放降低了32％以上.煤种对各种燃烧方式降低NOx的程度有明显影响,煤中单位氮含量的燃料比(固定碳/挥发分)越小,煤的热解气和部分气化生成气再燃以及解耦燃烧方式下NOx的排放量越低.在煤部分气化生成气再燃烧方式中,部分氧化气化段通氧量不同,降低NOx排放的效果也不同,在氧气体积分数为8％～10％时的NOx生成量最低.基于解耦燃烧技术原理,研制了1.4MW解耦燃烧工业锅炉,在燃烧同一煤种时,解耦燃烧锅炉和传统立式锅炉相比,烟气中NOx排放量降低了32.9％.%The reduction of NO, emission via different coal combustion methods was studied in a two-stage reactor using 3 different coals. The NO, formation is effectively suppressed by reburning the gas from pyrolysis and partial gasification of coal, making the NO, emission obviously lower than that of the air-staged combustion. It is found that the decoupling combustion leads to the higher NO, reduction rate, which is over 32% in comparison with the normal combustion. The NO, reduction rates vary with the coal properties. The smaller the fuel ratio (fixed carbon to volatile matter) at per nitrogen content in coal, the lower NO, emission is for reburning the combustible gas from pyrolysis and gasification and also for the decoupling combustion. The NO, emission due to reburning the partial gasification gas varies with the oxygen amount applied in the gasification, and the lowest NO, emission is realized in the oxygen concentration from 8% to 10%. A 1. 4 MW industrial boiler was designed according to the principle of the decoupling combustion technology. The running data for the same coal show that the decoupling combustion reduces 32.9% NOx emission in comparison with the traditional combustion.
展开▼
