超声雾化过硫酸钠联合氢氧化钙吸收脱硫脱硝

Ultrasonic atomization of sodium persulfate combined with calcium hydroxide absorption desulfurization and denitrification

使用超声雾化/紫外光/热量协同活化过硫酸钠(Na2S2O8)溶液,联合Ca(OH)2吸收作用,脱除烟气中的SO2和NO,获得了较高的脱除效率。实验研究了影响烟气中SO2和NO脱除的主要因素,并且对实验过程中的主要活性物质以及反应机理进行了分析。使用超声波雾化器产生的液滴d(50)值为7.2μm,粒径小于10μm液滴占总数的72%。超声雾化可以加速Na2S2O8溶液在受紫外光/热量协同活化时分解产生SO4^-·和·OH等自由基,提高污染物的脱除效率。Na2S2O8浓度、UV功率的升高会促进烟气中NO和SO2的脱除;烟气流量、溶液pH值等参数的升高不利于NO和SO2的脱除;烟气温度变化对NO的脱除具有双重影响。在最佳的条件下,NO和SO2的脱除效率分别为97.5%,86.3%。同时确定了该实验体系下脱硫脱硝过程中的主要活性物质为SO4^-·和·OH。

Ultrasonic atomization/ultraviolet light/heat synergistic activation of Na2S2O8 solution and combined with Ca(OH)2 absorption were used to remove SO2 and NO from flue gas.The main factors affecting the removal of SO2 and NO in flue gas were studied experimentally,and the main active substances and reaction mechanism in the experiment were analyzed.The droplets generated by ultrasonic nebulizer show d 50 value of 7.2μm,with 72%possessing the size less than 10μm.Ultrasonic atomization can accelerate the decomposition of Na2S2O8 solution to generate free radicals such as SO4^-·and·OH activated by ultraviolet light/heat,and improve the removal efficiency of pollutants.The increase of Na2S2O8 concentration and UV power will promote the removal of NO and SO2 in flue gas;the increase of flue gas flow and solution pH are not conducive to the removal of NO and SO2;the change of flue gas temperature has the double impact on NO removal.Under the optimal conditions,the removal efficiencies of NO and SO2 were 97.5%and 86.3%,respectively.At the same time,the main active substances in the desulfurization and denitrification process under the experimental system were determined to be SO4^-·and·OH.