用臭氧氧化技术同时脱除锅炉烟气中NO_x及SO_2的试验研究

Experimental Research for the Simultaneous Removal of NO_x and SO_2 in Flue Gas by O_3

对臭氧氧化锅炉烟气同时脱硫脱硝技术进行了基础试验研究，主要对臭氧的无催化热分解特性、臭氧与NO和SO2的氧化特性以及结合湿法洗涤的整体脱除效果进行了试验研究。研究结果表明臭氧在典型锅炉排烟温度150℃下10s内分解率为28％，该温度下臭氧的生存时间远长于其与NOx／SO2的动力学反应时间，对反应过程影响不大。在100～200℃范围内，臭氧均可以对NO进行高效氧化，在[O3][NO]=1．0时，NO氧化率分别达到了85．7％和84．8％，随温度升高，臭氧的分解速度加快，NO氧化效率不断下降，至400℃时已无氧化能力。SO2与03之间的氧化反应进行较弱，SO2氧化率最高达29．75％，有效温度为27～300℃。系统中加入200mL／m^3的SO2对O3／NO之间的氧化反应影响不大。通过结合尾部湿法洗涤，在[O3]／[NO]=0．9时，脱硫效率接近100％，脱硝效率达到86．27％。

The simultaneous removal of NOx/SO2 by O3 injection technology was investigated by experiment. The fundamental researches include the ozone decomposition property, O3/NO and O3/SO2 reaction kinetics, the overall removal efficiency of the NOx and SO2. Results show that the thermal decomposition of O3 is 28% at 150℃ in 10s. At this typical flue gas temperature, the lifetime of O3 is longer enough for the OflNO/SO2 reactions. In the range of temperature from 100℃ to 200℃, the NO can be oxidized efficiently by O3, The reaction characteristics at 100℃ and 200℃ are very similar, the NO oxidization efficiencies are 85.7% and 84.8% respectively at [O3]/[NO]=1.0. The O3 decomposition rate increases with the raising of temperature. As a result, the NO oxidization efficiency decreases when temperature is above than 200℃. There is non-effective when temperature is higher than 400℃. The reaction between O3 and SO2 is weak, the higher conversion rate is 29.75%, and the effect temperature range is 27～300℃. There is only minor influence to the O3/NO reactions when 200mL/m^3 SO2 is added to the system. In the assistance of wet washing tower, NOx and SO2 can be removed effectively by the ozone injection technology. The SO2 removal efficiency is nearly 100% and the NOx reduction efficiency is 86.27% at [O3]/[NO]=0.9.