División de Ciencias Ambientales, Instituto Potosino de Investigación Científica y Tecnológica (IPICyT), Camino a la Presa San José 2055, Lomas 4a Sección, 78216, San Luis Potosí, Mexico.
Centro de Innovación Aplicada en Tecnologías Competitivas, CIATEC AC, Omega no. 201 Col. Industrial Delta, 37545, León, Gto, Mexico.
Environ Sci Pollut Res Int. 2021 Mar;28(11):13970-13980. doi: 10.1007/s11356-020-11583-5. Epub 2020 Nov 17.
Bioaerosols are emitted during the biological treatment of water, soil, and air pollutants. The elimination of these pollutants has become a priority due to their detrimental effects on human health. Advanced oxidation technologies have been used to control bioaerosol emissions specially to improve indoor air quality. This investigation was focused on evaluating the biofiltration of ethyl acetate vapors in terms of removal efficiency and bioaerosol emission. Also, a continuous photocatalytic process to inactivate bioaerosols emitted from the biofilter was assessed as a post-treatment. The photocatalysis was developed with ZnO and TiO immobilized onto Poraver glass beads. Flow cytometry (FC) coupled with fluorochromes was used to characterize and quantify bioaerosol emissions in terms of live, dead, and injured cells. Ethyl acetate removal efficiencies were maintained in a steady state with values of 100% under 60-g m h inlet load (IL). Biomass concentration in the biofilter reached values up to 228 mg g at day 56 of operation, but the spontaneous occurrence of predatory mites diminished biomass concentration by 33%. Bioaerosols emitted during the steady-state operation of the biofilter were composed mainly by bacteria (~ 94%) and in a less extent of fungal spores (0.29-6%). The most efficient photocatalytic system comprised TiO/Poraver with 78% inactivation of bioaerosols during the first 2 h of the process, whereas the ZnO/Poraver system showed null activity (~ 0%) of inactivation. FC results show that the main mechanism of inactivation of TiO/Poraver was cell death.
生物气溶胶是在水、土壤和空气污染物的生物处理过程中排放的。由于它们对人类健康的有害影响，消除这些污染物已成为当务之急。高级氧化技术已被用于控制生物气溶胶排放，特别是为了改善室内空气质量。本研究重点评估了乙基乙酸酯蒸气的生物过滤在去除效率和生物气溶胶排放方面的性能。此外，还评估了连续光催化过程作为生物过滤器排放生物气溶胶的后处理。该光催化作用是通过将 ZnO 和 TiO 固定在 Poraver 玻璃珠上开发的。流式细胞术 (FC) 与荧光染料结合使用，用于根据活细胞、死细胞和受伤细胞来表征和量化生物气溶胶排放。在入口负荷 (IL) 为 60-g·m-3·h 的情况下，乙基乙酸酯去除效率保持在稳定状态，达到 100%。在运行的第 56 天，生物过滤器中的生物量浓度达到 228 mg·g-1，但捕食性螨虫的自然发生使生物量浓度降低了 33%。在生物过滤器稳定运行期间排放的生物气溶胶主要由细菌 (94%)组成，真菌孢子（0.29-6%）含量较少。最有效的光催化系统由 TiO/Poraver 组成，在过程的头 2 小时内，生物气溶胶的灭活效率达到 78%，而 ZnO/Poraver 系统的灭活效率为零（0%）。FC 结果表明，TiO/Poraver 的主要灭活机制是细胞死亡。
