论文标题    Numerical and experimental study on co-firing of low volatile coal in a 330 MW tangentially fired boiler
作者    Xing Liu, Jiaye Zhang, Houzhang Tan, Qingfeng Mo, Xuebin Wang, Yibin WANG
发表/完成日期    2021-03-17
期刊名称    Journal of the Energy Institute
论文简介    Burnout related problem occurs in the utility boiler burning low volatile coals. The infurnace co-firing of low volatile coal (LV) experiments and simulation were carried out in a tangentially fired PC furnace to investigate the effect of co-firing ratio, injection position and particle size on NO x emission and carbon in fly ash (C fh ). The results of full-scale experiment show that C fh increases from 2.16% to 4.21% as the LV cofiring ratio rises from 33% to 50%, while the NO x emission increases from 356.0 mg/Nm 3 to 385.2 mg/Nm 3 (@6% O 2 ). The model is validated against the experimental data. The numerical simulation results show that NO x increases from 308 mg/Nm 3 to 567 mg/Nm 3 when the co-firing ratio of LV increases from 0% to 100%, while C fh increases from 1.20% to 7.15%. It is found that the contribution of top two layers ( E and F ) to the total C fh is significantly higher than that of the other layers. Under the working conditions of burning bituminous coal in the bottom layer and lean coal (particle size 70 μ m ) in the upper five layers, C fh is 5.4%. When the particle size of lean coal in the five layers is reduced to 40 μ m , C fh rapidly decreases to 2.0 %. And the C fh can be reduced to 2.5% when only the top two layers feeding lean coal with small particle size (40 μm). Only 40% marginal cost of coal grinding is needed to reach the marginal benefit corresponding to 8 3 % C fh improvement while all layers of LV coal are ground into the small size.