前驅物對戴奧辛類化合物催化生成效應之研究

Study the Catalytic Effects of Precursors for PCDD/Fs Formation

陳建呈(Chien-Cheng Chen)

指導教授 ： 林傑

國立屏東科技大學/工學院/環境工程與科學系所/碩士(2009年)

https://doi.org/10.6346/NPUST.2009.00173

摘要

戴奧辛之前驅物質，如氯酚、氯苯、多環芳香烴等，藉由飛灰表面結合並與催化金屬作用，而縮合反應形成戴奧辛類化合物。由於戴奧辛於煙道中以粉狀活性碳噴注處理有效控制與吸附戴奧辛類化合物，但受到排氣擾動重新進入空氣污染防治設備或排放管道中之細小飛灰微粒可能因高比表面積催化再合成戴奧辛與呋喃污染物於污染防治設備中。本研究蒐集某廢棄物焚化爐之袋式集塵灰進行實驗室模擬研究。添加0.2 %之三氯酚及0.5 %之氯苯於飛灰中生成之戴奧辛濃度分別為27.9 ng/g及8.3 ng/g，兩者比較，添加三氯酚比添加氯苯之戴奧辛濃度高出2.4 倍。氯酚以PCDDs為主要戴奧辛濃度之優勢物種，而氯苯則以PCDFs為主要戴奧辛濃度之優勢物種。結果顯示氯酚可能比氯苯更易促成戴奧辛濃度之增加。添加0.2 %之三氯酚及0.1 %之五氯酚於飛灰中生成之戴奧辛濃度分別為27.9 ng/g及142.2 ng/g，顯示添加五氯酚比三氯酚於飛灰中增加之戴奧辛濃度高出了4.1倍，且PCDDs及PCDFs皆有增加之趨勢，顯示添加五氯酚於飛灰中會比添加三氯酚於飛灰中更易促成戴奧辛濃度之增加。添加0.1 %及0.2 %之五氯酚於飛灰中所生成PCDD/Fs濃度分別為 142.2 ng/g及166.0 ng/g，增加了約0.2倍，發現當隨著添加五氯酚濃度增加時，PCDD/Fs濃度增加量成正相關趨勢。無添加與添加二氯化汞於三氯酚及飛灰中，其戴奧辛濃度分別為27.9 ng/g及111.5 ng/g，顯示添加二氯化汞可能會造成三氯酚於飛灰中促進戴奧辛濃度增加，增加倍率約為3倍。添加氯酚類化合物、氯苯、二苯呋喃、多環芳香烴於飛灰中，生成之戴奧辛趨勢，氯酚類化合物與多環芳香烴會造成大量PCDDs之增加趨勢，而氯苯及二苯呋喃會造成大量PCDFs之增加趨勢。

關鍵字

飛灰 ； 戴奧辛 ； 2,4,6-三氯酚 ； 五氯酚

並列摘要

The precursors of Dioxin, such as chlorophenols, chlorobenzenes, and polycyclic aromatic hydrocarbons are combined with fly ash surface, the role catalytic metals, and a condensation reaction to form Dioxin compounds. A powdered activated carbon injection is used to effectively control and adsorb dioxin compounds in the flue. However, when the exhaust of the previous reaction is disturbed, small particles of fly ash may re-enter the air pollution prevention equipment to form dioxin and furan. In this study, the bag house of a waste incinerator was used in laboratory simulations. The results of the study show that adding 0.2% trichlorophenol onto fly ash forms a PCDD/Fs concentration of 27.9 ng/g, whereas adding 0.5% chlorobenzene onto fly ash forms a PCDD/Fs concentration of 8.3 ng/g. Therefore, the addition of trichlorophenol is more favorable than chlorobenzene because the trichlorophenol forms a dioxin concentration that is 2.4 times greater. Furthermore, adding 0.1% pentachlorophenol onto the fly ash produces a PCDD/Fs concentration of 142.2 ng/g, and adding 0.2% pentachlorophenol produces a PCDD/Fs concentration of 166.0 ng/g. Compared to the aforementioned trichlorophenol, the pentachlorophenol forms a dioxin concentration that is at least 4.1 times greater. Up to now, pentachlorophenol most effectively treats dioxin-type compounds in the flue. Also, increasing the concentration of pentachlorophenol subsequently increases the adsorbed concentration of PCDD/Fs. Further simulation revealed that the addition of mercurydichloride and trichlorophenol increased the PCDD/Fs concentration from 27.9 ng/g to 111.5 ng/g. Certainly, the mercurydichloride triples the adsorption of dioxin compounds. In conclusion, adding chlorophenol compounds, chlorobenzene, diphenyl furans, and polycyclic aromatic hydrocarbons onto fly ash generated positive trends of PCDD/Fs adsorption. The addition of chlorophenol compounds and polycyclic aromatic hydrocarbons resulted in large positive trends of PCDDs species adsorption. The addition of chlorobenzene and dibenzofurans resulted in large positive trends of PCDFs species adsorption.

並列關鍵字

Fly Ash ； PCDD/Fs ； 2,4,6-Trichlorophenol ； Pentachlorophenol

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