烧结过程中CO还原NO的模拟研究

Simulation of NO Reduction by CO in Sintering Process

为了考察烧结过程中烧结矿各主要组分对NO脱除反应的影响,研究了有O2和无O2条件下CO还原NO的反应规律,并在还原性气氛下对烧结矿催化还原NO进行了动力学分析。在500～1 000℃,分别以CaO、MgO、Fe2O3和烧结矿为填料层,在固定床石英反应器中研究NO的脱除规律。研究结果表明,不同填料对CO还原NO反应催化作用的强弱顺序为CaO〉烧结矿〉Fe2O3〉MgO。烧结矿作用下,CO体积分数为1.2%时,NO的转化率可达90%以上,CO还原NO反应的Arrhenius曲线以780℃为界分为两段,两段的反应机理不同。反应体系中O2存在时不利于NO还原反应的进行。

To investigate the effects of the major components of sintering ore on NO reduction in sintering process, the reduction of NO by CO with or without oxygen was performed. The dynamics of the reduction of NO by CO under the action of sinter ore was calculated. The NO reduction was studied in a fixed bed quartz reactor using calcium oxide, magnesium oxide, ferric oxide and sinter ore as bed materials at temperature ranging from 500 ℃ to 1 000 ℃. The results showed that the catalytic effects on the reduction of NO by CO were as follows： CaO〉sinter ores〉 FezO3〉MgO. Under the action of sinter ore, the conversion of NO was over 90% when the volume fraction of CO was 1.2%. The break in the Arrhenius plot at 780 ℃ suggested that the reaction mechanism was changed in the dynamics calculation. The presence of oxygen did not favor the reduction of NO.