| 摘要: | 本研究針對國內某大型燃油電廠進行煙道排氣之採樣分析，並就FPM、FPM2.5、CPM及PAHs濃度及排放特性進行探討。研究燃油電廠與相同空氣污染防制設備(ESP)的兩個機組(A、B機組)之煙氣排放，另於B機組於鍋爐低負載(B1)及高負載(B2)條件進行排氣特性之比較。結果顯示A組及B1組鍋爐煙囪排放之FPM濃度分別為0.14及0.17 mg/Nm3，FPM2.5 排放濃度為0.11及0.09 mg/Nm3，而兩座燃油鍋爐之CPM排放濃度分別為24.0及60.2 mg/Nm3，皆遠高於FPM；B機組負載由3成提升至8成時，FPM及FPM2.5 濃度皆呈上升趨勢，濃度分別為1.10及0.60 mg/Nm3，FPM2.5為3成負載之6.5倍，而CPM濃度為65.0 mg/Nm3，與原負載條件相比並無明顯變化，顯示負載對FPM排放影響較CPM顯著。PAHs部分，A組及B1組之PAHs總濃度分別為3.10及2.30 μg/Nm3，而B2組之PAHs濃度為2.44 μg/Nm3，三組之氣固相分布均以氣相為主，PAHs物種分布方面， 以Nap、2-MN及Pyr為主要排放物種；毒性當量方面，A、B1及B2組之PAHs毒性當量濃度分別為48.4、5.0及13.5 ng-BaPeq/Nm3，其中BcFE及BaP為主要之貢獻物種。另外，排放係數計算結果顯示燃油電廠A組每燃燒1公升重油之FPM、FPM2.5、CPM及PAHs排放量分別為1.7、1.3、288及0.04 mg；而B1及B2組則分別為2.3、1.2、818、0.03 mg及14.1、7.7、834、0.03 mg。顯示CPM之排放係數皆遠高於FPM，而負載是影響FPM排放係數的重要因素，研究結果顯示鍋爐負載及溫度對PAHs及PM排放有一定之影響，值得進一步探討以降低污染物之排放。此外由於SCR 觸媒對PAHs具去除效力，本研究亦針對商用 SCR 觸媒於電廠操作條件下探討不同溫度對Ant之去除效率，結果顯示其去除效率為96-99%。;The flue gas emitted from an oil-fired power plant was sampled to analyze the concentrations and characteristics of FPM, FPM2.5, CPM and PAHs. Two boilers (A and B) with the same air pollution control device (APCD) were studied, and the flue gas characteristics of boiler B under different loads were discussed. The results show that the FPM concentrations emitted from the stacks of boilers A and B are 0.14 and 0.17 mg/Nm3, respectively, and the FPM2.5 concentrations are 0.11 and 0.09 mg/Nm3, respectively, while the CPM concentrations of the two boilers are 24.0 and 60.2 mg/Nm3, respectively. As the load of boiler B is increased from 30% to 80%, both FPM and FPM2.5 concentrations reveal upward trends, and the concentrations measured are 1.10 and 0.60 mg/Nm3, respectively, which are 6.5 times that of the 30% load. On the other hand, the CPM concentration is 65.0 mg/Nm3, which does not vary significantly compared with the original load condition, indicating that the effect of load on FPM emission is more significant than that of CPM. In the PAHs part, the total PAHs emitted from boiler A and boiler B are 3.10 and 2.30 μg/Nm3 respectively, while the PAHs concentration of boiler B at 80% load is 2.44 μg/Nm3, and the PAHs are mainly distributed in gas-phase. In terms of toxicity, the toxic equivalent concentrations of boiler A (A), boiler B 30% load (B1) and boiler B 80% load (B2) are 48.4, 5.0 and 13.5 ng-BaPeq/Nm3, respectively, with BcFE and BaP being the main contributing congeners. In addition, the emission factors calculated on the basis of fuel consumption indicate that the FPM, FPM2.5, CPM and PAHs emitted from boiler A of the oil-fired power plant are 1.7, 1.3, 288 and 0.04 mg/L; and the B1 and B2 are 2.3, 1.2, 818, 0.03 mg/L and 14.1, 7.7, 834, 0.03 mg/L, respectively. It shows that the emission factor of CPM is much higher than that of FPM, and the load is the main factor affecting the emission factor of FPM. The results show that boiler load and flue gas temperature have a certain influence on PAHs and PM emissions, and efforts are needed for further reduction of pollutant emissions. In addition, this study also investigates the removal efficiencies of PAHs achieved with commercial SCR catalyst at different temperatures (325°C - 400°C) and the results show that the efficiencies are within the range of 96–99%. |
