Numerical simulation of MILD combustion on coal-water slurry
Duan Yansong
Zhang Liqi
Mao Zhihui
Zhu Xinyang
Hu Yi
Zheng Chuguang
Abstract：In order to solve the problems of poor operation stability of CWS (coal-water slurry) combustion,the MILD (moderate or intense low oxygen dilution) combustion characteristics of CWS were studied numerically based on the pilot-scale furnace of IFRF.Results show that under the same fuel input,the MILD combustion of CWS has extensive backflow region than the conventional swirl combustion,more intense flue gas circulation,lower and more uniform distribution of furnace temperature.The maximum peak temperature is reduced by 227 K.The rate of combustion reaction is slower,and the area of combustion reaction zone is larger.The whole furnace is in a low oxygen atmosphere,and the emission of NOx is dramatically reduced by more than 50％.In addition,different concentrations CWS have little effect on flow distribution,but it can lower the temperature in the whole furnace and reduce the final NOx emission.
Keywords：coal-water slutty (CWS)MILD combustionconventional swirl combustionNOx emissionnumerical simulation
Publication Date：2017-01-01