空气分级对旋风燃烧液态排渣及NOx排放的影响

Influence of Staged Air on Liquid Slagging and NOx Reduction of Cyclone Combustion

为了进一步论证在旋风炉中采用空气分级低氮燃烧技术的可行性,建立了旋风燃烧液态排渣模型和NOx排放半经验公式,并在一台中试旋风炉上开展了实验研究,定量分析了空气分级对准东煤旋风燃烧时液态排渣、NOx排放和燃尽性的影响.实验数据表明,针对不同准东煤种,为兼顾稳定液态排渣和降低氮氧化物排放,可根据容积热负荷、捕渣率和灰临界温度确定合适的空气配比方式.燃用准东天池煤时,最佳的主燃区过量空气系数为0.9,与空气未分级相比,NOx排放可降低20%,但未完全燃烧热损失会增加0.32%.本研究将为旋风炉的设计和运行提供重要参考.

The feasibility of staged air combustion in the cyclone furnace needs to be further demonstrated.In this paper,the liquid slagging model of cyclone combustion was built and the semi-empirical formulas for NOx emission were derived,and the experiments were conducted on a pilot cyclone furnace,to research the influences of staged air on liquid slagging,NOx emission and coal burnout of cyclone combustion of Zhundong coal.The results indicate that,in order to stabilize liquid slagging and reduce NOx emission,the appropriate air mixing mode can be determined by volume heat load,slag capture rate and ash critical temperature for different Zhundong coals.The optimal excess air coefficient for combustion zone is 0.9 when burning Tianchi coal,the NOx emission can be reduced by more than 20%,while the heat loss due to incomplete combustion will increase by 0.32%.This study will provide important reference for the design and operation of cyclone furnace.