利用小型室內環境暴露艙評估三種生物氣膠控制技術之去除效能

Evaluation of the Removal Efficiency of Three Type Bioaerosol Controlling Technologies by Using a Small Indoor Environmental Test Chamber

本研究利用小型暴露艙評估中性電解次氯酸水噴霧、奈米碳管電漿技術、石墨烯負離子等3種生物氣膠去除技術效能。暴露艙測試選用大腸桿菌（E.coli）做為測試生物氣膠，生物氣膠是利用Collison three-jet nebulizer產生，採樣則是以BioStage impactor進行採樣，採樣時間為10秒。整體暴露艙環境條件設定在換氣率1.0（1/hr）與相對濕度30%，進行生物氣膠去除實驗。當去除設備未開啟時，E. coli生物氣膠在換氣率為0與1.0（1/hr）控制條件下，自然衰減率分別為0.028與0.187（1/min）。生物氣膠去除實驗結果顯示，中性電解次氯酸水噴霧在自由餘氯為50 ppm濃度下，暴露艙中E. coli生物氣膠衰減常數為0.501（1/min）；奈米碳管電漿放電技術在6 kV之放電條件下，暴露艙中E. coli生物氣膠衰減常數為0.283（1/min）；石墨烯負離子對於E. coli生物氣膠去除測試中，暴露艙中E. coli生物氣膠衰減常數為0.217（1/min）。3種去除設備在開啟後20～40分鐘內，暴露艙中生物氣膠濃度均會降至0CFU/m^3。3種生物氣膠去除技術均具有有效之生物氣膠去除能力。

This work evaluated the bioaerosol removal efficiency of three bioaerosol removal technologies, including neutral electrolyzed water spraying, carbon nanotube plasma, grapheme negative air ions in an indoor environment-simulated chamber. E. coli bioaerosol was chosen as the challenging bioaerosol. Bioaerosols were generated using a Collison three-jet nebulizer and sampling by BioStage impactor. The air exchanged rate and relative humidity of the chamber was set at 1.0 (1/hr) and 30%. The natural decay coefficient under ACH 0 and 1.0 (1/hr) was 0.028 and 0.187 (1/min). The removal coefficient under ACH 1.0 (1/hr)was 0.501 (min-1) for E. coli of FAC 50 ppm neutral electrolyzed water spraying; the removal coefficient under ACH 1.0 (1/hr) was 0.283 (min-1) for E. coli against 6 kV carbon nanotube plasma; the removal coefficient was 0.217 (min-1) for E. coli against grapheme negative air ions was. When these three removal technologies were working, the bioaerosol concentration would decrease to CFU/m^3 within 20 to 40 minutes. These finding indicated that three bioaerosol removal technologies have effective bioaerosol removal capability.