Department of Environmental Management, School of Health Sciences, University of Occupational and Environmental Health, Yahatanishi-ku, Kitakyushu, Japan.
J Occup Health. 2010;52(2):125-31. doi: 10.1539/joh.l9144. Epub 2010 Feb 23.
Thermal reconditioning characteristics of organic vapors from a respirator cartridge were studied by introducing humid air into a cartridge that had adsorbed organic vapors in order to develop a thermal reconditioning method.
Five different organic vapors (methanol, 2-propanol, acetone, dichloromethane and methyl acetate), most of which have relatively weak adsorption affinity to charcoal, were used in this study. Adsorption was carried out at a temperature of 25 degrees C. The relative humidity of the adsorption air with organic vapor was 50%. When the vapor concentration in the downstream of the respirator exceeded the breakthrough concentration, that is, the occupational exposure limits in Japan, the vapor supply was stopped. Then, desorption was started by introducing clean humid air from opposite side of the cartridge under a heated condition. When the desorbed vapor concentration fell below the limit of quantification, desorption process was ended and the next adsorption cycle was started after the temperature had returned to room temperature. This adsorption - desorption cycle was repeated more than three times. The desorption temperature was 65 degrees C and the relative humidity of desorption air was 20%, 50% or 70% at 25 degrees C.
When the relative humidity was 20%, the breakthrough times of regenerated cartridges were shorter than that of a new one, but no difference was observed in the breakthrough curves when the relative humidity was greater than 50%.
The results suggest that the thermal reconditioning of respirator cartridges using humid air is possible for these vapors.
通过向吸附有机蒸气的滤盒中引入湿空气，研究了来自呼吸防护器具滤盒的有机蒸气的热再生特性，以开发一种热再生方法。
本研究使用了五种不同的有机蒸气（甲醇、2-丙醇、丙酮、二氯甲烷和乙酸甲酯），其中大多数对活性炭的吸附亲和力较弱。吸附在 25°C 的温度下进行，吸附空气中的相对湿度为 50%。当呼吸防护器具下游的蒸气浓度超过突破浓度，即日本的职业暴露限值时，停止蒸气供应。然后，在加热条件下从滤盒的相反侧引入清洁的湿空气开始解吸。当解吸的蒸气浓度低于定量下限时，结束解吸过程，在温度回到室温后开始下一个吸附循环。这个吸附-解吸循环重复了三次以上。解吸温度为 65°C，在 25°C 时解吸空气的相对湿度为 20%、50%或 70%。
当相对湿度为 20%时，再生滤盒的突破时间短于新滤盒，但当相对湿度大于 50%时，突破曲线没有差异。
结果表明，对于这些蒸气，使用湿空气对呼吸防护器具滤盒进行热再生是可行的。
