Study on Indoor CO2 Control using a Lab-Scale CO2 Adsorption System

초록

Indoor CO2 level in subway is guided to keep lower than 2,500 ppm during non-rush hour, and 3,500 ppm during rush hour. Ventilation is one of the easiest ways to lower indoor CO2 level, but many particulate pollutants may come into the car duriong ventilation. In addition, Ventilation may cause thermal discomfort of passengers in winter or summer season because cold or hot comes into the car. In this study, solid type CO2 adsobent made of alkali metal was used to control indoor CO2 level by adsorption. A small lab-scale CO2 adsorption system was prepared, and installed in a 5m^3 enviromental chamber. CO2 level change with and without the operation of the CO2 adsorption system was investigated while CO2 is constanly supplied by breathing of humans. when this CO2 adsorption system was not turn on, CO2 level increased drastically and linearly to reach more than 8,000 ppm in 30 minutes. However, when the CO2 adsorption system was turn on, CO2 level reached only 6,000 ppm. Develoment of more efficient CO2 adsorbent is prerequisite condition for practical application of this system to indoor space. Regeneration of used CO2 adsorbent is another project to be studied.