常壓電漿反應器處理廚房油煙廢氣中多環芳香烴化合物之研究

Removal of Polycyclic Aromatic Hydrocarbons from Cooking Fumes Using an Atmospheric Plasma Reactor

張弘昌(Hung-Chang Chang)

指導教授 ： 謝連德 ； 趙浩然

國立屏東科技大學/工學院/環境工程與科學系所/博士(2013年)

https://doi.org/10.6346/NPUST.2013.00092

摘要

電漿技術近年來已廣泛應用在環境毒性物質處理。在空氣毒物中多環芳香烴化合物(Polycyclic Aromatic Hydrocarbons；PAHs）之研究備受重視。由於廚房排放油煙廢氣中PAHs被證實具高致突變性與致癌性，廚房油煙暴露及排放廢氣對人體呼吸道健康具有危害性。因此，本研究開發一種油煙處理新技術。研究中，利用自行設計常壓電漿反應器搭配不同輸出功率BP17A(0.112 kJ/m3)、BP24A(0.138 kJ/m3)、BP30A(0.156 kJ/m3）串聯濕式洗滌塔(水洗滌/酵素洗滌)進行廚房油煙廢氣之PAHs處理實驗。此外，為探討電漿反應中活物種組成，藉由光纖(Optical Fiber, 200 μm)與光譜儀(Ocean Optics，型號HR 4000CG)進行常壓電漿光學發射光譜(Optical Emission Spectroscopy; OES)分析，並對電漿活性物種進行定性定量分析。另一方面，利用計算流體力學(Computational fluid dynamics；CFD)方法進行常壓電漿反應器處理PAHs之數值模擬，並將模擬值與實驗數據進行比較解析，以瞭解電漿處理反應中較為重要之分解反應路徑。模擬時，以前處理軟體GAMBIT 2.4.6繪製3D常壓電漿反應器網格以及利用ANSYS FLUENT內建RNG k-ε turbulence模式與Eddy Dissipation Concept Combustion模式進行數值求解。實驗結果顯示：(i)氣相PAHs物種中的Acenaphthylene(Acpy)在電漿功率BP24A與BP30A去除率分別為65.2%及83.8%；Acenaphthene(Acp)在電漿功率BP24A與BP30A去除率分別為48.6%及26.4%；Anthracene(Ant)在電漿功率BP24A與BP30A去除率為42.1%及29.5%；Benz[a]anthracene(BaA)在電漿功率BP24A與BP30A去除率為 53.8%及33.1%。電漿功率對氣相PAHs去除率效能為BP30A>BP24A> BP17A。(ii)常壓電漿反應器光學發射光譜分析到活性物種為在300-599 nm波長範圍發現有活性物種C（492.6 nm、505.2 nm、538 nm）、C2（516.4 nm、563.3 nm）、CH（314.4 nm）、CN（359 nm、388 nm）、Hγ（433.9 nm）、N2（357 nm、580.4 nm）、N2+（427.8 nm）、NO（237 nm）、C+（386.9 nm）、NH（337 nm）、O2+（526 nm、545 nm）；在600-900 nm波長範圍發現有活性物種N2（646.9 nm、891.2 nm）、H2（601.8 nm）、O（846.3 nm）、N（746.8 nm）存在。顯示出隨著功率增加，圖譜中譜線強度(Intensity)呈現增大的趨勢。(iii) 在電漿功率BP24A電漿反應器內氣相PAHs物種中的Acenaphthylene(Acpy)數值模擬值去除率為61.3%與實際電漿反應器65.2%約有6%誤差值。

關鍵字

常壓電漿 ； 廚房油煙 ； 多環芳香烴化合物 ； 計算流體力學 ； 光學發射光譜 ； 空氣毒物

並列摘要

Plasma technology is becoming increasingly vital for treating various environmental toxic pollutants. The toxics of polycyclic aromatic hydrocarbon are critical in the field of air toxics. Numerous studies have shown that production from cooking oil fumes (COFs), especially for polycyclic aromatic hydrocarbons (PAHs), has adverse effects on people health. The emission of PAHs is a serious problem because of its mutagenicity and carcinogenicity. This study investigates the decomposition efficiency of PAHs emitted from kitchens using an atmospheric plasma reactor (APR) with different input power wattages, including BP17A (0.112 kJ/m3), BP24A (0.138 kJ/m3), and BP30A (0.156 kJ/m3) with wet scrubbing tower (water/bio-solution (NOE-7F) scrubbing). In addition, we explore the plasma state by using optical emission spectroscopy (OES) and an optical fiber with a spectrometer (HR4000CG) to reveal its changes. Moreover, this study also presents the simulation of an APR by using a method based on computational fluid dynamics (CFD). A commercial CFD tool was used to solve mass, momentum, and energy equations. The commercial ANSYS FLUENT code was then used to simulate the Acpy compound by using a 3D APR to treat the cooking fume exhaust emitted from a restaurant kitchen. An in-house-reduced chemical mechanism was coupled with the CFD code for an improved computational runtime. The reactivity of the system was considered with the RNG k-ε turbulence model and the classic Eddy dissipation concept (EDC) combustion model. The results showed that (a) for Acpy, the removal efficiencies for BP24A and BP30A were 65.2% and 83.8%, respectively. For Acp, the removal efficiencies for BP24A and BP30A were 48.6% and 26.4%, respectively. Similarly, for Ant, the removal efficiencies for BP24A and BP30A were 42.1% and 29.5%, respectively. For BaA, the removal efficiencies for BP24A and BP30A were 53.8% and 33.1%, respectively. For total gaseous PAH concentrations, the removal efficiency was highest for BP30A, followed by BP24A, and then BP17A. (b) Consequent to OES measurement, the occurrence of 300-599 nm, C (492.6, 505.2, 538 nm), C2 (516.4 and 563.3 nm), CH (314.4 nm), CN (359 and 388 nm), Hγ (433.9 nm), N2 (357 and 580.4 nm), N2+ (427.8 nm), NO (237 nm), C+ (386.9 nm), NH (337 nm), O2+ (526 and 545 nm) and 600-900 nm, N2 (646.9 and 891.2 nm）, H2 (601.8 nm), O (846.3 nm), and N (746.8 nm) were observed. (c) The simulation results were compared with the experimental temperature measurement and the removal efficiency of Acpy. The simulated average removal efficiency of Acpy was 61.3%.

並列關鍵字

Atmospheric Plasma ； Cooking Oil Fume ； Polycyclic Aromatic Hydrocarbons ； Computational Fluid Dynamics ； Optical Emission Spectroscopy ； Air toxic

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