Airborne Fungi Inactivation Using an Absorption Dehumidification System

Abstract

The evaluation of airborne fungal inactivation efficiency by a pilot absorption dehumidification system was investigated in this study. The comparison of two liquid desiccants, TEG (triethylene glycol) and LiCl (lithium chloride), was also illustrated. Two one-stage Anderson samplers of 400 orifices attached to malt extract agar plates with the addition of chloramphenicol were installed in the inlet and outlet of the absorption dehumidification system to collect airborne fungi. The results showed that the best fungal inactivation efficiency, 93.2%, was obtained for TEG absorption system under the conditions: air flow rate, 1.5 kg·m-2 s-1; liquid flow rate, 4.97 kg·m -2 s-1; liquid inlet concentration, 89.5%; and liquid inlet temperature, 24.5°C. Most of the fungal inactivation efficiencies for TEG absorption system were higher than that for LiCl absorption system. The result implied that keeping at room temperature was a better strategy when operating an absorption dehumidification. The study also provided measurement data for the evaluation of fungal inactivation efficiency for liquid desiccants in pilot test and demonstrated the feasibility of an absorption dehumidification system for inactivating airborne fungi to maintain a better indoor air quality environment. The result would provide useful information for application of the absorption dehumidification system to air-conditioning industries for maintaining healthy indoor environments.