Graduate Institute of Environmental Engineering, National Central University, Chungli, 320, Taiwan.
Graduate Institute of Environmental Engineering, National Central University, Chungli, 320, Taiwan.
Chemosphere. 2020 Mar;243:125443. doi: 10.1016/j.chemosphere.2019.125443. Epub 2019 Nov 22.
Long-term sampling is essential for monitoring the air pollutants emitted from stack since it can monitor the pollutants emission continuously including the stages of start-up, shutdown and normal operation. However, commercial continuous sampling equipment such as AMESA faces the challenges of high weight and complicated sampling procedures. This study has developed a long-term and automatic sampling system (National Central University continuous stack sampling system, NCU-CS), and compared the efficiency with manual sampling train (MST). The results indicate that relative standard deviation (RSD) of PCDD/Fs concentrations measured between NCU-CS and MST is <20%, demonstrating that the difference between NCU-CS and MST in measuring PCDD/Fs is insignificant. Besides, the effects of adsorbent temperature, adsorbent amount and type of adsorbent on breakthroughs of PAHs and unintentional-persistent organic pollutants (UPOPs) such as polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs), chlorinated phenols (CPs), chlorinated benzenes (CBs) and polychlorinated naphthalenes (PCNs) are evaluated. The results indicate that the breakthrough of pollutants increases with increasing temperature of XAD-2 and decreases with increasing XAD-2 amount. Moreover, XAD-4 is used as alternative adsorbent to test the breakthrough and the results indicate that the breakthroughs of UPOPs of XAD-4 as adsorbent are lower than that with XAD-2 due to higher specific surface area of XAD-4. Furthermore, the residual of PCDD/Fs with NCU-CS as the sampling train is relatively low (1.5-3.8%), which meets the regulation of EN 1948-5 (10%).
长期采样对于监测烟囱排放的空气污染物至关重要，因为它可以连续监测污染物的排放，包括启动、关闭和正常运行阶段。然而，商业连续采样设备如 AMESA 面临着重量大、采样程序复杂等挑战。本研究开发了一种长期自动采样系统（国立中央大学连续烟囱采样系统，NCU-CS），并将其与手动采样系统（MST）的效率进行了比较。结果表明，NCU-CS 和 MST 测量的 PCDD/Fs 浓度的相对标准偏差（RSD）<20%，表明 NCU-CS 和 MST 在测量 PCDD/Fs 方面的差异不显著。此外，还评估了吸附剂温度、吸附剂用量和吸附剂类型对多环芳烃和无意持久性有机污染物（UPOPs）如二恶英和呋喃（PCDD/Fs）、多氯联苯（PCBs）、氯苯酚（CPs）、氯苯（CBs）和多氯萘（PCNs）穿透的影响。结果表明，随着 XAD-2 温度的升高，污染物的穿透量增加，而随着 XAD-2 用量的增加，穿透量减少。此外，还使用 XAD-4 作为替代吸附剂来测试穿透情况，结果表明，由于 XAD-4 的比表面积更高，因此作为吸附剂的 UPOPs 的穿透量低于 XAD-2。此外，NCU-CS 作为采样系统，PCDD/Fs 的残留量相对较低（1.5-3.8%），符合 EN 1948-5（10%）的规定。
