UV/H2O2氧化联合CaO吸收脱除NO的传质-反应动力学

在实验室规模的光化学反应器中,基于实验研究﹑动力学理论以及双膜理论,研究了UV/H₂O₂氧化联合CaO吸收(UV/H₂O₂-CaO工艺)脱除燃煤烟气中NO的传质-反应动力学。分析了NO吸收的传质-反应过程,明确了NO吸收过程的主要控制步骤和强化措施,测定了关键的动力学参数,推导了NO吸收过程的理论模型。结果表明:在实验范围内,NO吸收速率随着NO浓度的增加几乎呈线性增加。随着H₂O₂浓度和CaO浓度的增加,NO的吸收速率均呈现先增加后变缓的趋势。UV/H₂O₂-CaO工艺脱除NO是一个拟一级快速反应过程,强化气相主体扰动﹑增加气液接触面积和提高NO分压可有效提高NO的吸收速率。NO吸收速率方程的计算值和实验值具有较好的一致性。

Mass transfer-reaction kinetics for NO removal by combination process of UV/H2O2 oxidation and CaO absorption

Based on experimental results,kinetics and two-film theory,the mass transfer-reaction kinetics was experimentally studied for NO removal using a combination process of UV/H₂O₂ oxidation and CaO absorption(UV/H₂O₂-CaO process) in a lab-scale UV-bubbling column reactor.The mass transfer-reaction process of NO absorption was analyzed to determine its rate controlling step and some measures that can effectively strengthen NO absorption,and some key kinetic parameters were measured and a theoretical model for NO absorption was established.The results indicate that under experimental conditions,the rate of NO absorption almost linearly increases with NO concentration.With increase of H₂O₂ and CaO concentrations,the efficiencies of NO removal increase greatly at first,and then its change is small.The absorption of NO by combined UV/H₂O₂-CaO process follows pseudo-first-order kinetics.The NO absorption rate can be effectively strengthened by increases of turbulence in gas phase body,gas-liquid contact area and NO partial pressure.The values calculated from the theoretical model of NO absorption are in good agreement with the experimental values.