Objective: To effectively reduce the concentration of poisons in cleanroom, protect the health of workers, realize the optimization and automatic control of the new return air device. And the influence of initial concentration, air volume, temperature and relative humidity of formaldehyde on the purification effect of the new return air device was explored. Methods: The purification effect of the new return air device installed with the activated carbon and the photocatalyst purification net or ordinary activated carbon purification network was tested in a 60 m(3) simulated cleanroom. The concentration of formaldehyde was determined by solution absorption-phenol reagent spectrophotometry. Based on the single factor experiment to determine the combination of two purification nets. The effects of air volume, initial formaldehyde concentration, temperature and relative humidity on the purification effect of the new return air device were investigated by orthogonal test. Then, the performance parameters of the return air device to purify formaldehyde were determined. Results: The formaldehyde purification efficiency of the two types of purification nets in the new return air device was higher than that of the ordinary activated carbon purification network (P<0.05) . The combination of activated carbon and photocatalyst purification net has no effect on the formaldehyde purification efficiency of the return air device (P>0.05) . According to the direct analysis and variance analysis, air volume was the most sensitive factor (F value is 18.894, P<0.05) , followed by initial concentration (F value is 16.128, P<0.05) , while temperature and relative humidity have little effect (F value is 0.041 and 0.599, respectively, P>0.05) . LSD analysis showed that there was no significant difference in the purification efficiency of formaldehyde between 475 m(3)/h and 626 m(3)/h (P>0.05) . From the perspective of formaldehyde purification efficiency and energy saving, when the air volume is set to 475 m(3)/h, the new return air device has higher purification efficiency for high concentration of formaldehyde. Conclusion: The new return air device consisting of activated carbon and photocatalyst purification net can play a good purification role in cleanroom with different temperatures and different humidity. Its formaldehyde purification efficiency is affected by air volume and initial concentration.
目的： 为有效降低洁净厂房毒物浓度，保护劳动者健康，实现新型回风装置优化及其自动控制，探讨甲醛初始浓度、风量、温度、相对湿度对新型回风装置净化效果的影响。 方法： 在60 m(3)的模拟洁净厂房内，对安装有普通活性炭净化网、活性炭与光触媒净化网组合的新型回风装置15 min净化甲醛效率进行测试。采用溶液吸收-酚试剂分光光度法测定甲醛浓度，在单因素试验确定两种净化网组合方式的基础上，采用正交试验，探讨风量、甲醛初始浓度、温度、相对湿度对新型回风装置净化效果的影响，确定回风装置净化甲醛的性能参数。 结果： 新型回风装置中两种净化网组合方式的甲醛净化效率均高于普通活性炭净化网（P<0.05）。通过正交试验直接分析和方差分析显示，风量是最敏感的影响因素（F=18.894，P<0.05），其次是初始浓度（F=16.128，P<0.05），而温度、相对湿度几乎没有影响，差异均无统计学意义（F=0.041、0.599，P>0.05）；LSD分析显示，风量475 m(3)/h与626 m(3)/h净化甲醛效率差异无统计学意义（P>0.05），从甲醛净化效率和节能角度综合考虑，风量设定为475 m(3)/h时，新型回风装置对高浓度的甲醛有较高的净化效率。 结论： 由活性炭与光触媒净化网组成的新型回风装置在洁净厂房不同温度、湿度的情况下，均能较好地发挥净化甲醛的作用，风量、初始浓度对其净化效率有影响。.
Keywords: Activated carbon; Clean room; Formaldehyde; New return air device; Photocatalyst.