Process control is an effective approach to reduce the NO_(x) emission from sintering flue gas.The effects of different materials adhered on coke breeze on NO_(x) emission characteristics and sintering performance wer...Process control is an effective approach to reduce the NO_(x) emission from sintering flue gas.The effects of different materials adhered on coke breeze on NO_(x) emission characteristics and sintering performance were studied.Results showed that the coke breeze adhered with the mixture of CaO and Fe_(2)O_(3) or calcium ferrite significantly lowers the NO_(x) emission concentration and conversion ratio of fuel-N to NO_(x).Pretreating the coke with the mixture of lime slurry and iron ore fines helped to improve the granulation effect,and optimize the carbon distribution in granules.When the mass ratio of coke breeze,quick lime,water and iron ore fines was 2:1:1:1,the average NO_(x) emission concentration was decreased from 220 mg/m^(3) to 166 mg/m^(3),and the conversion ratio of fuel-N was reduced from 54.2%to 40.9%.展开更多
Fe-ZSM-5 catalysts modified by Cu and Ce by aqueous solution ion-exchange and incipient wetness impregnation methods were tested in the selective catalytic reduction of NO_(x) with NH_(3).A variety of characterization...Fe-ZSM-5 catalysts modified by Cu and Ce by aqueous solution ion-exchange and incipient wetness impregnation methods were tested in the selective catalytic reduction of NO_(x) with NH_(3).A variety of characterization techniques(NH_(3)-SCO,BET,XRD,XPS,UV-Vis,NH_(3)-TPD,H_(2)-TPR)were used to explore the changes of the active sites,acid sites and pore structure of the catalyst.It was found that the dispersion of active Cu species and Fe species had great influences on the catalytic activity in the whole catalytic process.The Cu doping into the Fe-ZSM-5 catalyst produced new active species,isolated Cu ions and CuO particles,resulting in the improved low-temperature catalytic activity.However,the NH_(3) oxidation was enhanced,and part of the Fe^(3+)active sites and more Brønsted acidic sites in the catalyst were occupied by Cu species,which causes the decrease of the high-temperature activity.The recovery of hightemperature activity could be attributed to the recovery of active Cu species and Fe species promoted by Ce and the promotion of active species dispersion.The results provide theoretical support for adjusting the active window of Febased SCR catalyst by multi-metal doping.展开更多
基金Project(2017YFC0210302)supported by the National Key R&D Program of ChinaProjects(U1660206,U1760107)supported by the National Natural Science Foundation of China
文摘Process control is an effective approach to reduce the NO_(x) emission from sintering flue gas.The effects of different materials adhered on coke breeze on NO_(x) emission characteristics and sintering performance were studied.Results showed that the coke breeze adhered with the mixture of CaO and Fe_(2)O_(3) or calcium ferrite significantly lowers the NO_(x) emission concentration and conversion ratio of fuel-N to NO_(x).Pretreating the coke with the mixture of lime slurry and iron ore fines helped to improve the granulation effect,and optimize the carbon distribution in granules.When the mass ratio of coke breeze,quick lime,water and iron ore fines was 2:1:1:1,the average NO_(x) emission concentration was decreased from 220 mg/m^(3) to 166 mg/m^(3),and the conversion ratio of fuel-N was reduced from 54.2%to 40.9%.
基金Project(51906089)supported by the National Natural Science Foundation of ChinaProject(NELMS2018A18)supported by the National Engineering Laboratory for Mobile Source Emission Control Technology,China+1 种基金Project(XNYQ2021-002)supported by the Provincial Engineering Research Center for New Energy Vehicle Intelligent Control and Simulation Test Technology of Sichuan,ChinaProject(GY2020016)supported by the Zhenjiang City Key R&D Program,China。
文摘Fe-ZSM-5 catalysts modified by Cu and Ce by aqueous solution ion-exchange and incipient wetness impregnation methods were tested in the selective catalytic reduction of NO_(x) with NH_(3).A variety of characterization techniques(NH_(3)-SCO,BET,XRD,XPS,UV-Vis,NH_(3)-TPD,H_(2)-TPR)were used to explore the changes of the active sites,acid sites and pore structure of the catalyst.It was found that the dispersion of active Cu species and Fe species had great influences on the catalytic activity in the whole catalytic process.The Cu doping into the Fe-ZSM-5 catalyst produced new active species,isolated Cu ions and CuO particles,resulting in the improved low-temperature catalytic activity.However,the NH_(3) oxidation was enhanced,and part of the Fe^(3+)active sites and more Brønsted acidic sites in the catalyst were occupied by Cu species,which causes the decrease of the high-temperature activity.The recovery of hightemperature activity could be attributed to the recovery of active Cu species and Fe species promoted by Ce and the promotion of active species dispersion.The results provide theoretical support for adjusting the active window of Febased SCR catalyst by multi-metal doping.