Experiment study and optimization reformation of the SNCR of the pulverized coal industrial fired boiler

DUAN Lu

doi:10.3969/j.issn.1007-7677.2024.02.008

Abstract：The use of the Selective Non Catalytic Reduction(SNCR)need to overcome the problems of the low deni-trification efficiency and serious ammonia escape.The optimization experiment was carried out to improve the denitrifi-cation performance of types of boiler furnace.Based on coal powder industrial boiler SNCR test system,by experimen-tally measuring the temperature distribution of two types of furnace structures and different capacities of coal powder industrial boilers,the influence of the number of spray guns and temperature on SNCR denitrification performance is explained,the SNCR of the 15 boilers of four heating stations were optimizing modified.The holes of the spray gun and the electromagnetic flowmeters were added and the pipelines were reformed for the SNCR system.The effective-ness of SNCR optimization and transformation were further evaluated.The results shown that the denitrification effi-ciency with two spray guns is higher than that with one spray gun,which is mainly depended on the temperature distri-bution.The optimal denitrification reaction temperature and ammonia nitrogen substance ratio should be obtained,and the optimal spray gun position for boiler SNCR should be found.When the average temperature of the furnace cross-section is 800～900℃and the ammonia nitrogen ratio is 1.5～2.0,SNCR can achieve good denitrifica-tion efficiency and low ammonia escape;the dosage of denitrification reagents before and after the renovation of the heating station were analyzed,the dosage of urea is decreased by 23.2%compared with that before optimization reformation and the dosage of liquid oxygen is reduced by 75.3%.The urea and liquid oxygen consumption after the renovation were significantly reduced,which indicates that the SNCR renovation of the heating station can significantly reduce the operating cost of coal powder boilers.