1 School of Metallurgy Engineering , Anhui University of Technology , Ma��anshan 243002 , Anhui , China 2 Key Laboratory of Metallurgical Emission Reduction and Resources Recycling, Ministry of Education , Anhui University of Technology , Ma��anshan 243002 , Anhui , China
Effect of.metallurgical dust on.NO.emissions during.coal combustion process
1 School of Metallurgy Engineering , Anhui University of Technology , Ma��anshan 243002 , Anhui , China 2 Key Laboratory of Metallurgical Emission Reduction and Resources Recycling, Ministry of Education , Anhui University of Technology , Ma��anshan 243002 , Anhui , China
ժҪ NO emissions from coal combustion are receiving signi. cant attention in recent years. As a solid waste generated from metallurgical industry, metallurgical dust (MD) contains a large amount of metal oxides, such as Fe2O3, CaO, SiO2 and Al2O3, as well as other rare metal oxides. The in.uence of MD on the NO emissions and the mechanism of the coal com-bustion systems were analyzed. The results show that the peak values of NO emission decrease with the increase in MD mass percent, and the curve of NO emission can be divided into two stages including rapid generation (400.600.��C) and slow release (800.900.��C). The reduction of NO is signi. cantly a.ected by temperature, volatile components, O2 and CO. CO has a signi.cant catalytic action which can deoxidize NO to N2. The results obtained by X-ray di.raction and scanning electron microscopy indicate that multiple components in MD, such as Fe9TiO 15, Fe2O3 and TiO 2, can react with NO to produce TiN. Besides, the alkali metals in MD, such as Na, K and Ca, may catalyze NO precursor to inhibit NO emission. These results indicate that MD is cheap and highly e.cient in controlling NO emissions during coal combustion processes.
Abstract��NO emissions from coal combustion are receiving signi. cant attention in recent years. As a solid waste generated from metallurgical industry, metallurgical dust (MD) contains a large amount of metal oxides, such as Fe2O3, CaO, SiO2 and Al2O3, as well as other rare metal oxides. The in.uence of MD on the NO emissions and the mechanism of the coal com-bustion systems were analyzed. The results show that the peak values of NO emission decrease with the increase in MD mass percent, and the curve of NO emission can be divided into two stages including rapid generation (400.600.��C) and slow release (800.900.��C). The reduction of NO is signi. cantly a.ected by temperature, volatile components, O2 and CO. CO has a signi.cant catalytic action which can deoxidize NO to N2. The results obtained by X-ray di.raction and scanning electron microscopy indicate that multiple components in MD, such as Fe9TiO 15, Fe2O3 and TiO 2, can react with NO to produce TiN. Besides, the alkali metals in MD, such as Na, K and Ca, may catalyze NO precursor to inhibit NO emission. These results indicate that MD is cheap and highly e.cient in controlling NO emissions during coal combustion processes.
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