折流式管状反应器对室内甲醛的净化效果

Purifying effect of baffled tubular reactor on indoor formaldehyde

利用PCO技术,针对现有的室内挥发性有机污染物,设计一种能与建筑空调系统的通风换气设备相结合的折流式管状反应器,以甲醛为目标污染物,对其净化效果进行实验分析。结果表明:折流式管状反应器对于甲醛的降解处理效果高于传统的管状反应器,其转化率及矿化率均大于传统管状反应器;相较于波长较长的黑光灯,波长为254 nm的杀菌灯利用率更高,实验效果优于黑光灯;不同初始浓度下甲醛的反应有效度η基本不受催化层厚度影响;以波长254 nm的杀菌灯为紫外光源时,由于光强衰减快,使得催化层厚度对传质速率无明显作用;以波长为365 nm的黑光灯为紫外灯源时,甲醛η值随催化层厚度增加而增大,故在此实验条件下的光催化反应中,紫外光吸收量、反应速率以及反应有效度均会随催化剂负载量增加而增大。

Using the PCO technology, aiming at the existing indoor VOCs, the baffled tubular reactor which can be combined with ventilation equipment in the air conditioning system of building is designed. Formaldehyde was chose as the target pollutant and analyse its purification effect. The result shows that the effect of degrading the formaldehyde in the tubular reactor is higher than that of the traditional tubular reactor, and the conversion rate and mineralization rate of the baffled tubular reactor are greater than the traditional tubular reactor. Compared with the black light that have longer wavelength, the sterilizing lamp with the wavelength of 254 nm is more efficient, and the experimental result is better than the black light. The reaction effectiveness η of the formaldehyde at different initial concentrations is not affected by the thickness of the catalyst layer. When using the sterilizing lamp with the wavelength of 254 nm. For ultraviolet light source, the thickness of the catalytic layer has no significant effect on the mass transfer rate due to the fast attenuation of light intensity. Also when the black light with a wavelength of 365 nm is using as an ultraviolet light source, the η value of formaldehyde will increase with the increase of the catalyst loading. Therefore, in the photocatalytic reaction under this experimental condition,the amount of ultraviolet light absorbed, the reaction rate, and the effectiveness of the reaction will increase as the catalyst loading increases.