Sterilization effectiveness of in-duct ultraviolet germicidal irradiation system in liquid desiccant and indirect/direct evaporative cooling-assisted 100% outdoor air system
| 주 저자 | Jong-Il Bang, Joon-Young Park, Ye-Lim Jo, Jae-Weon Jeong, Anseop Choi, Minki Sung |
|---|---|
| 공동 저자 | - |
| 소속 | - |
| Abstract | Microorganism contamination in air conditioning systems can cause respiratory diseases in building occupants. This study aims to evaluate and predict the performance of an in-duct ultraviolet germicidal irradiation (ID-UVGI) system to reduce the microorganisms that can grow in the liquid desiccant and indirect/direct evaporative cooling-assisted 100% outdoor air system (LD-IDECOAS). Bacteria and mold on the direct evaporative cooling (DEC) element and in the outdoor and supply air were monitored using a swab and Petrifilm for surfaces and impact sampler for air during the operation of the LD-IDECOAS. Microbial contamination was first verified in the air before performing the sterilization experiment. The experimental results showed that the airborne bacteria were reduced by 78.3% after the operation of the ID-UVGI system but there was almost no reduction in the airborne mold. The bacteria and mold concentration on the DEC surface were decreased by 99.7% and 96.7% respectively 3?h after the ID-UVGI operation. Even after the ID-UVGI system was operated for 6 days, the microbial contamination in the downstream water was not decreased significantly; the inside of the DEC element was suspected to be improperly sterilized. The operating times of the ID-UVGI system needed to inactivate the microorganisms were predicted from the UV?C intensity distribution by irradiation analysis. Legionella sp. and Penicillium sp. were predicted to be inactivated by 99.9% with UV?C exposures of 6?s and 15?min 57?s or less respectively when the LD-IDECOAS is operated at the highest air flow rate. |
| Keyword | - |
| 페이지 | pp. 1~11 |
| 논문 파일 | 없음 |
| 게재일시 | - |
| DOI | - |
| 학회/저널명 | Building and Environment Vol.186 |
| 년도 | 2020 |
| 추가 문구 | 107350, https://doi.org/10.1016/j.buildenv.2020.107350 |
| 등록 일시 | 2025-06-18 14:50:37 |