二氧化氯氧化处理甲醛废气的探索试验研究

Experimental study of treating formaldehyde exhaust by using chlorine dioxide oxidation

以瓷环填料塔为反应装置,研究CIO_2对甲醛的去除效果。试验考察了甲醛质量浓度、进口气体流量、C1O_2液体流量以及C1O_2质量浓度对甲醛去除效率的影响。最佳工艺条件为:甲醛气体质量浓度80～180 mg/L,进口气体流量120～280 L/h,C1O_2液体流量1～3mL/min,C1O_2质量浓度40 mg/L。甲醛的去除率随甲醛质量浓度、C1O_2质量浓度的增加而升高,去除率变化由98%至99%接近100%;而甲醛去除率随进口气体流最的增大略呈下降趋势。

The article aims to search for a new method for purifying the formaldehyde exhaust in high concentration by using ClO2. Our experimental research was done in a device of reaction column filling with porcelain ring, in which ClO2 and HCHO are allowed to come into contact with each other. In so doing, we have mainly studied the removing efficiency of formaldehyde exhaust and the influence by formaldehyde concentration on the incoming air flow and ClO2 concentration and that of ClO2 fluid flow. The experimental results show that, with the increase of ClO2 and formaldehyde concentration, the formaldehyde-removing efficiency tends to rise. However, with the increase of the air flow, the removing rate tends to decrease. Nevertheless, with the increase of the import of ClO2 fluid flow, little change would happen. Statistically speaking, when the concentration of ClO2 increased from 5 mg/L to 100 mg/L, the removal rate would increase from 89.56% to 99.99%, with the formaldehyde concentration increase from 6.31 mg/L to 182.62 mg/L, the formaldehyde removing rate is likely to increase from 98.91% to 99.98%. However, when the air flow increased from 120 L/h to 280 L/h, the removing rate would remain steady in a range of 99.9%. Nevertheless, when the import of ClO2 fluid flow rose from 1.45 mL/min to 9.60 mL/min, the removing rate tended to stabilize with no change at all with the fluctuations kept at 0.55%. When the formaldehyde concentration in range of 80-180 mg/L, the import air flow was 120-280 L/h and import liquid ClO2 flow was 1-3 mL/min, the concentration of ClO2 was 40 mg/L, the removing efficiency could reach almost as high as 100%. Thus, the research has proved that the removing rate in high formaldehyde concentration would be better and feasible both from the point of view of theory and experiment.