Adsorptive Removal of Indoor Carbon Dioxide by Using Carbonate Salt

초록

CO2 is one of the most well-known greenhouse gas, and its capture and storage from stack gases have been studied extensively. However, CO2 of indoor space is also gaining wide attention due to its adverse effect on the residents. Since CO2 is generated during the breathing of residents in indoor spaces, CO2 concentration is apt to be high when the ventilation is not enough. High concentration of CO2 is known to cause headache, drowsiness, and dizziness for residents. Ventilation is most commonly applied to reduce CO2 concentration, but ventilation is not available when the outdoor air is severely polluted. For subway cabin, since the tunnel air is polluted by particulate matters, ventilation may worsen the indoor air quality. For this reason, there have been several efforts to reduce CO2 concentration by adsorption. In this study, carbonate salt was used as CO2 adsorbent to reduce indoor CO2. Carbonate can adsorb CO2, and it can be easily regenerated by heating. Carbonate salts was pelletized by mixing with substrate, while the mixing ratio was varied. Carbonate salts and substrate was pretreated under various temperature conditions to investigate the effect of treatment temperature. CO2 adsorption performances of prepared carbonate salts were studied by using a lab-scale CO2 adsorption testing equipment. The effect of reaction temperature and relative humidity was also investigated.