NUMERICAL STUDY ON NOX REDUCTION DURING MICRONIZED COAL REBURNING
Three dimensional numerical simulation of micronized coal reburning in full-scale tangentially fire boiler was conducted by using CFD method. Bituminous coal was chosen as reburn fuel to study the effects of reburn zone length, the height of reburn nozzles, the stoichiometry ratio in reburn zone, the reburn fuel fraction and the reburn coal fineness on NOx emissions. The results indicated that when the relative height of reburn nozzles was about 0.210 and the stoichiometry ratio was between 0.8 and 0.9 in reburn zone, the NOx reduction efficiency reached the largest value. NOx reduction efficiency increased with reburn zone length and reburn fuel fraction. The optimum reburn fuel fraction is 20％. NOx reduction efficiency increased with the reduction of reburn coal particle size. The optimum particle size of reburning fuel is 20μm. Compared with conventional coal reburning, micronized coal reburning is superior. This technology not only has less influence on combustion efficiency but also has higher NOx reduction efficiency.
Micronized coal NOz reduction Numerical simulation Full-scale boiler
Yanyan JIA Mingshu BI Zhi LIU
School of Chemical Engineering, Dalian University of Technology, Dalian 116012, Peoples Republic of China
国际会议
第六届煤燃烧国际会议(The 6th International Symposium on Coal Combustion)
武汉
英文
315-321
2007-12-01（万方平台首次上网日期，不代表论文的发表时间）