环境测试舱表面吸附甲醛的规律

Adsorption of Formaldehyde on the Surface of Environmental Test Chamber

对环境测试舱进行了25d跟踪测试,包括甲醛本底浓度测试、甲醛释放、甲醛浓度衰减、通风换气和舱内表面吸附甲醛重新释放各阶段,考察环境测试舱内甲醛吸附消耗量及重新释放规律,探索有效控制措施.结果表明,环境测试舱中甲醛浓度C的变化符合对数函数C=Alnt+B[舱内甲醛释放时A>0,B>0,舱内甲醛衰减时A<0,B>0,t为时间(h)],其中A与舱内吸附甲醛释放后再次达到相对平衡的浓度密切相关;采用抽气式通风换气系统有利于舱内残余甲醛的消减,关闭此通风换气系统后,舱内甲醛浓度初期浓度快速递增,在相对较低的甲醛浓度(0.3203mg/m3)时再次达到相对平衡;环境测试舱内吸附程度与基体表面吸附比θ和撞到基体表面的吸附质的物质的量U有关.

The tracking experiments in an environmental test chamber for 25 d were carried out, including the stages of intrinsic formaldehyde concentration test, formaldehyde release, formaldehyde concentration attenuation, ventilation and formaldehyde release after it was adsorbed on the chamber surface. So it is necessary to investigate its releasing rules in order to improve the subsequent testing and propose guidance on the control of indoor pollution. The research results show that the formaldehyde concentration （C） in the chamber changes consistent with a logarithmic function： C=Alnt＋B [when formaldehyde in the chamber releases, A〉0, B〉0, when formaldehyde attenuates, A〈0, B〉0, t is time （h）], where A is closely related to the relative equilibrium concentration established again after the adsorbed formaldehyde releases. Using suction type ventilation system for the chamber is in favor of residual formaldehyde reduction. After closing the ventilation system, the initial concentration of formaldehyde in the chamber increases quickly, and then a relatively low concentration of formaldehyde （0.320 3 mg/m3） will be established again in balance. Adsorption degree of formaldehyde in the chamber is related to the substrate surface adsorption ratio Oand hitting quantity of the adsorbate on the substrate surface U.