Enhancement of Gas Absorption by utilizing Condensation and Mist formation

保护地球环境是21世纪最受关注的问题。高效气体吸收技术是保护地球环境的重要技术之一。与一般的物理气体吸收一样，下降液膜和/或喷雾方法受液膜中气体扩散输运速率的支配。因此，即使采用声波对液膜进行外部扰动、分散小液滴而增加表面积等方法，吸收率的提高也是有限的。从这一观点出发，本研究旨在寻求高性能的气体吸收方法。提出了利用冷凝过程和雾状形成吸收气体的新概念，并进行了垂直冷却管内水冷凝率和包括雾状形成率在内的气体吸收率的验证实验。对冷凝液和雾滴在冷却管中的吸收速率进行了理论分析，并与实验数据进行了比较，验证了本文提出的概念，阐明了冷凝液和雾滴吸收气体的机理。在此基础上，获得了物理气体吸收过程的基本知识.

Protection of global environment is the gravest concern in the 21st century. High efficiency of gas absorption may be one of the important techniques for protection of global environment. The falling liquid film and/or the spray methods as the general physical gas absorption were dominated by the rate of gas diffusion transport in the liquid film. So that the enhancement of absorption rate is limited, even if any improvement such as the external disturbance of liquid film by a sound wave, the increase of surface are due to dispersed small droplets and so on were applied.From this standpoint, this study has been conducted to pursue a high-performance gas absorption method. A new concept of gas absorption by utilizing condensation process and mist formation was proposed, and its proof experiment was conducted with regard to the water condensation rate and the gas absorption rates in vertical cooling tube including mist formation rate. Theoretical analyzes were performed on the gas absorption rates of the condensate formed on the cooling tube surface and of the mist droplets in the tube.Comparing the analytical results with the experimental data, the concept proposed in this paper was identified and mechanism of the gas absorption through the condensate and/or the mist droplets was clarified. On the basis of these findings, the fundamental knowledge of physical gas absorption process was obtained.