| 摘要: | 污水處理廠被觀察到可以藉由氣液交換的廢水處理程序釋放大量的生物氣膠和懸浮微粒到空氣中，而這些微粒可能包含著人體機會性病原體，或是藥物類新興污染物。有鑑於此，全面性的調查及表徵污水處理廠空氣環境中的氣膠微粒之物理、生物及化學特徵至關重要。故在本研究中，主要目的為表徵由污水處理廠生成之微粒在全粒徑尺度下的粒徑分以及生物氣膠的分布特徵。此外，紫外線氣動粒徑分析儀（UV-APS; 型號3314;TSI, USA）用於即時性的監測污水處理廠空氣環境中的活性生物氣膠。同時利用高流量採樣器（HV-RW; 型號 080130-1203; SIBATA, Japan）收集空氣樣品以分析新興污染物在污水處理廠的排放狀況，以及在曝氣池所生成的微粒中的分布情形。
位於台灣北部的污水處理廠被選為本次研究的調查對象。實驗設計了兩種不同的採樣模式，一種採樣模式為在距離曝氣池（AM）一公尺遠處進行量測；另一種模式為靠近曝氣池水面處（CAT）進行量測。基於數目濃度的情況下，全尺度的粒徑分布呈現單峰分布且由奈米級微粒所支配，其占整個粒徑分布約99%；而基於體積的情況下，分布則呈現雙峰，峰值分別落在0.5-0.7 μm 以及2-3 μm。針對UV-APS 所揭示的微粒生物特徵結果顯示，熒光信號的峰值位於3-4 μm 左右，這意味著大多數的熒光微粒可能是細菌群聚體或是真菌物種。另一項值得注意的是本研究在空氣和水的樣品中分析出了九種常見的新興污染物，包括全氟辛磺酸（PFOS）、苯并三唑（Benzotriazole）、甲苯基三唑（Tolyltriazole）、持續性糖衣錠（Pentoxifylline）、脫水紅黴素（Erythromycin-H2O）、克拉黴素（Clarithromycin）、K 他命（Ketamine）、甲基安非他命（Methamphetamine）以及全氟辛酸（PFOA）。而這些化學物質中以脫水紅黴素（191.45 pg/m3）和甲基安非他命（39.02 pg/m3）在空氣中含量最多，且主要存在於PM1.0 之中。;Urban wastewater treatment plants (UWTPs) could be an emission source of bioaerosols and particle matters into the air through the air-liquid exchange process and
bubble-jet-droplet mechanism. It poses the potential of spreading human opportunistic pathogen and pharmaceutical emerging pollutants in wastewater into the air. In view of the potentials of emission and exposure risks of airborne particles in UWTPs, there is a need to comprehensively characterize the physical, biological and chemical characteristics of particles emitted from UWTPs. The main objective of this study is to characterize the
wide-size-range particle size distribution (PSD) and the characteristics of bio-aerosols generated in a UWTP. In addition, the ultraviolet aerodynamic particle sizer (UV-APS; model 3314; TSI, USA) was used to detect viable bio-aerosols in real time. Meanwhile, the air samples were also collected by high-volume samplers (HV-RW; model 080130-1203; SIBATA, Japan) for investigating the occurrence and the distribution of emerging
pollutants on the particles emitted from the aeration tank.
The measurements were conducted at two sampling ports in a UWTP located in northern Taiwan. One is 1 meter away from aeration tank (AM), and the other is close to the water surface of the tank (CAT). On the number-based, the full particle size distribution exhibits a unimodal distribution and dominated by nanoparticles, which is
accounted for about 99% of the whole PSD. On the volume-based, the distribution exhibits dual peaks and the modes of particle size are located at 0.5-0.7 μm and 2-3 μm. For the results of the biological characteristics revealed by UV-APS, the peaks of the fluorescent signal were sitting around 2-3 μm, implying that the most of fluorescence particles may be bacteria aggregates or fungal species. In addition, the concentration of the bio-aerosols in the UWTPs may be underestimated by the traditional cultivating method. Moreover, pharmaceuticals and emerging pollutants can also be transferred into the air. Nine common emerging contaminants, including PFOS, Benzotriazole, Tolyltriazole, Pentoxifylline, Erythromycin-H2O, Clarithromycin, Ketamine, Methamphetamine, PFOA were analyzed and found in both air and water samples. Among them, the most abundant
chemicals in the air are Erythromycin-H2O (191.45 pg/m3) and Methamphetamine (39.02 pg/m3) and mainly reside on PM1.0. |
