Analysis of affecting factors of activated coke denitrationefficiency for sintering flue gas
ZHANG Wei-li1, WU Sheng-li1, HU Zhong-jie1,2
1. School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083, China; 2. Iron Plant, Baoshan Iron and Steel Co., Ltd., Shanghai 201900, China
Abstract:In order to clarify the denitration performance changes of activated coke during the recycling process in the sintering flue gas purification system and the main operating parameters affecting the denitration rate of sintering flue gas,to improve the purification efficiency of sintering flue gas by activated coke method,FTIR and simulation experiments were carried out to study the changes of activated coke property and its effect on denitration efficiency during recycling. The main process parameters affecting the activated coke denitration efficiency for sintering flue gas and its influence law were clarified through statistical analysis of production data. The results show the quantity of phenol and quinine on activated coke increase after recycling,hence the NO adsorption capacity decreases,which leads to the decrease of initial denitration efficiency of active coke. While the pre-adsorption of ammonia can greatly increase the initial denitration efficiency,it can be deduced that the denitration efficiency from top to bottom of cross-flow denitration tower experienced 100%,rapid decreasing,slow rising until equilibrium. Secondly,denitration efficiency is positively correlated with the NH3-NOx ratio,O2 volume percent,NOx mass concentration,and desorption temperature,and negatively correlated with the H2O volume percent,SO2 mass concentration,flue gas flow,and activated carbon bed temperature. Besides,NH3-NOx ratio,O2 volume percent,and NOx mass concentration have great influence on the denitration efficiency,which should be focused on in the parameter optimization process.
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