固體廢棄物焚化衍生飛灰中之戴奧辛類化合物分佈特性

本研究為探討廢棄物焚化廠焚化衍生飛灰中戴奧辛類化合物分佈、毒性當量及特徵剖面。結果顯示，廢棄物焚化爐（MSWI）和事業廢棄物焚化爐（IWI）兩廠之袋式灰與混合灰PCDD/Fs濃度皆以OCDD濃度最高物種，MSWI袋式灰和混合灰濃度分別為1.44 ng/g和1.31 ng/g，IWI袋式灰和混合灰濃度分別為0.0213±0.00546 ng/g和0.0200±0.00759 ng/g，兩廠之袋式灰與混合灰中PCDFs濃度均大於PCDDs，表示戴奧辛類生成機制皆為De Novo反應大於Precursor反應。MSWI袋式灰與混合灰毒性當量濃度分別為0.0657 ng WHO -TEQ/g和0.0357 ng WHO -TEQ/g，IWI袋式灰與混合灰毒性當量濃度分別為1.42×10-3±2.40×10-4 ng WHO -TEQ/g和7.69×10-4±1.32×10-4 ng WHO -TEQ/g。MSWI袋式灰與混合灰毒性當量濃度分別為0.0786 ng WHO -TEQ/g和0.0317 ng WHO -TEQ/g，IWI袋式灰與混合灰毒性當量濃度分別為3.13E×10-3±4.19×10-4 ng WHO -TEQ/g和1.70×10-3±4.42×10-4 ng WHO -TEQ/g。毒性主要貢獻物皆為PCDFs，其次為PCDDs、DL-PCBs。MSWI污防前與袋式灰之PCDD和PCDF比值皆小於1，表示兩者戴奧辛類生成機制相同為De Novo反應大於Precursor反應；排放管道與袋式灰之PCDD和PCDF比值不相似，排放管道戴奧辛類生成機制為Precursor反應大於De Novo反應。IWI污防前、排放管道和袋式灰之PCDD和PCDF比值不相似，表示戴奧辛類生成機制不相似，IWI污防前和排放管道戴奧辛類生成機制為Precursor反應大於De Novo反應；IWI袋式灰戴奧辛類生成機制相似為De Novo反應大於Precursor反應。利用微環境模式模擬兩座焚化廠之袋式集塵器之戴奧辛化合物分佈，發現到實際值和模擬值的濃度趨勢MSWI較IWI相似。

關鍵字

戴奧辛類化合物；都市固體廢棄物焚化爐；事業廢棄物焚化爐；分佈特性；戴奧辛生成機制

並列摘要

This study investigate the distribution of dioxins in the incineration-derived fly ash of waste incineration plants. The results showed that the PCDD/Fs concentrations of baghouse filter ash and mixed ash from municipal solid waste incineration（MSWI）and industrial waste incineration（IWI）has the highest concentration of OCDD. The concentrations of MSWI baghouse filter ash and mixed ash were 1.44 ng/g and 1.31 ng/g respectively, while the concentrations of IWI baghouse filter ash and mixed ash were 0.0213±0.00546 ng/g and 0.0200±0.00759 ng/g respectively. The PCDFs concentrations in the baghouse filter ash and mixed ash of the two plants were both higher than PCDDs concentrations, indicating that the formation mechanism of dioxin-like is more in line with De Novo reaction than Precursor reaction. The PCDD/Fs concentrations of MSWI baghouse filter ash and mixed ash were 0.0657 ng WHO -TEQ/g and 0.0357 ng WHO -TEQ/g respectively, while the concentrations of IWI baghouse filter ash and mixed ash were 1.42×10-3±2.40×10-4 ng WHO-TEQ/g and 7.69×10-4±1.32×10-4 ng respectively. The PCDD/Fs TEQ concentrations in MSWI baghouse filter ash and mixed ash were 0.0786 ng WHO -TEQ/g and 0.0317 ng WHO-TEQ/g respectively, while the TEQ concentrations of IWI baghouse filter ash and mixed ash were 3.13E×10-3±4.19×10-4 ng WHO-TEQ/g and 1.70×10-3±4.42×10-4 ng WHO-TEQ/g respectively. PCDFs has a higher toxicity contribution proportion in ash, followed by PCDDs and PCBs. The ratios of PCDD and PCDF between MSWI pre-fouling and baghouse filter ash were below 1, indicated that they have the same dioxin-like generation mechanism, which is more in line with the De Novo Synthesis than the Precursor reaction, while the ratios of PCDD and PCDF between the discharge pipelines and baghouse filter ash were different, indicated that the dioxin-like generation mechanism is more in line with the Precursor reaction than the De Novo Synthesis. The PCDD and PCDF ratios of IWI pre-fouling, discharge pipelines and baghouse filter ash were different, indicated that they have different generation mechanism of dioxin-like. The generation mechanism of dioxin-like of IWI pre-fouling and discharge pipeline is more in line with the Precursor Reaction than the De Novo Synthesis; while the generation mechanism of dioxin-like of IWI baghouse filter ash is more in line with the De Novo Synthesis than the Precursor reaction. The micro-environment model is used to simulate the distribution of dioxin compounds in baghouse filter ash collectors of two incineration plants, it demonstrates that the actual concentration trend and the stimulated concentration trend of MSWI was similar as compared to IWI.