Influence of dioxin reduction on chemical composition of sintering exhaust gas with adding urea

• Published in: Journal of Central South University 2012-05, Vol.19 (5), p.1359-1363
• Main Authors: Long, Hong-ming, Li, Jia-xin, Wang, Ping
• Format: Article
• Language: English
• Subjects: Engineering; Metallic Materials
• ISSN: 2095-2899; 2227-5223
• DOI: 10.1007/s11771-012-1150-y

With the addition of urea as an inhibitor, four groups of reducing dioxin emission experiments in sintering pot were conducted. The results show that, adding 0.05%, 0.1% and 0.5% (mass fraction) urea, the emission concentrations of dioxin are 0.287, 0.258 and 0.217 ng-TEQ/m 3 , respectively. The dioxin emission rates drop substantially compared to 0.777 ng-TEQ/m 3 free of urea. With an increase of the urea content, the concentration of SO 2 emission reduces sharply. (NH 4 ) 2 SO 4 , formed by the reaction of SO 2 and NH 3 , goes into the dust and part of NH3 is released before reaction with the emission of exhaust gas. The NO x emission presents an increasing trend because the reaction of NH 3 and O 2 at high temperature produces NO x . Based on the consideration of factors such as the effect of reducing dioxin emission, and the chemical composition of exhaust gas, 0.05% is the optimum adding content of urea.