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The coal-fired utility boilers produce nitrogen oxides (NOx) is one of the major pollutants in the atmosphere. With the gradual improvement of the environmental protection requirements, the coal-fired power station flue gas denitrification imminent, urgent need of low-cost, efficient denitrification technology. Advanced reburning technology will reburning with SNCR combined with good technical and economic advantages, is expected to become the mainstream technology of our control NOx emissions of coal-fired power station. Firstly, by a two-stage reaction is one-dimensional combustion reactor coal reburning, SNCR and coal advanced reburning denitrification test, study reburning zone stoichiometric equivalent ratio (SR), coal reburning (RFP), the temperature of the reburning zone (T1), NH3/NO molar ratio (NSR), and the residence time (τ) of pulverized coal the advanced reburning denitration studied and to analyze the impact of the reburning zone exit conditions on the reaction system downstream of the NOx reduction reaction. The test results show that: Considering SR = about 0.8 compared suitable overall advanced reburning off denitration; the SR = 0 ~ 0.6 range within, an RFP = 25% of the advanced reburning the off highest denitration efficiency, the SR = the range of 0.8 ~ 1.2, of RFP = 15% of the advanced reburning the highest denitration efficiency; reburning fuel with nitrogen inputs of the reducing agent is present in an amount to an optimal ratio value, T1 = 1250 ° C, T2 = 900 ° C under the conditions, RFP = 20% NSR = 1, advanced reburning The highest efficiency of denitrification, RFP = 10% NSR = 1.5, advanced reburning denitrification highest efficiency; the advanced reburning T1 best value 1100 ° C; the reburning paragraph export NO, NH3, CH4, CO, HCN, affecting advanced reburning denitrification efficiency gas composition, studies show, the three gases CH4, CO, HCN, advanced reburning denitrification reaction promoted, CH4 and HCN advanced reburning, and the impact of CO is relatively small. Then integration of existing reburning and SNCR reaction mechanism of this article, application software Chemkin chemical kinetics model simulate pulverized coal advanced reburning reaction process, the test results and the simulation results are compared, to verify the correctness and availability of the integration mechanism. Finally, the pulverized coal advanced reburning generate rate analysis, study the important primitive reaction of important reaction objects such as the efficiency of denitrification, and the normalized generation rate coefficients describe the process of de-NOx reaction of conduct, drawing advanced reburning reaction denitration path and react with conventional reburning The SNCR reaction denitration path comparison. The results showed that: The advanced reburning denitration reaction is based on amino led, reburning fuel play an important role in the reduction reaction of the substance that functions in the denitrification process, three off important intermediate product, it is important reactive groups have undergone a change, but NH2 common an important intermediate product in the three processes, OH is a common reactive groups in the three reactions.
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