H_2O_2氧化-碱液吸收脱除NO_x的工艺研究

Study on Removal Technique of Nitrogen Oxides by H_2O_2 Oxidation-Alkali Liquor Absorption

针对制药行业NOx废气氧化度低、间歇排放的特点,提出了H2O2氧化-碱液吸收脱除NOx的方法。考察了H2O2质量分数、喷淋密度、氧化时间对NOx氧化度的影响以及氧化度、碱度对NOx吸收率的影响。结果表明,当温度为25℃、气体流量为8m3.h-1、NOx进口浓度为5000～6000mg.m-3、H2O2质量分数为2.5%、氧化时间为13s、H2O2喷淋密度为15m3.m-2.h-1时,NOx氧化度最高,达到67.2%;当NOx氧化度为50%、碱度为30g.L-1时,NOx吸收率最高,达到96.1%。

Removal of nitrogen oxides by H2O2 oxidation-alkali liquor absorption was proposed according to the feature of low oxidation degree and intermittent discharge of NOx waste gas from pharmaceutic industries.The effects of H2O2 mass fraction,H2O2 spray density,oxidation time on NOx oxidation degree and the effects of NOx oxidation degree,alkalinity on the absorption rate of NOx were investigated.The results showed that NOx oxidation degree could reach 67.2% under the optimum conditions as follows：the temperature was 25℃,the gas flow rate was 8 m3·h-1,the NOx initial concentration was 5000~6000 mg·m-3,the H2O2 mass fraction was 2.5%,the oxidation time was 13 s,the H2O2 spray density was 15 m3·m-2·h-1.The alkali absorption experiment indicated that when NOx oxidation degree was 50% and alkalinity was 30 g·L-1,the absorption rate of NOx could reach 96.1%.