水萃研磨程序對都市垃圾焚化飛灰重金屬穩定之影響

The effect of water extraction and ball milling process on heavy metals stabilization of MSWI fly ash

陳達松(Da-Sung Chen)

指導教授 ： 高思懷

淡江大學/工學院/水資源及環境工程學系碩士班/碩士(2008年)

https://doi.org/10.6846/TKU.2008.00455

摘要

都市垃圾焚化灰渣回收再利用已成為未來的趨勢，但中飛灰為性質複雜具有高鹼性，部分所含重金屬易於溶出，經常超過有害廢棄物認定標準，因此穩定飛灰中有害物質再利用為重要課題。濕式球磨可提供飛灰物理機械能(mechanical energy)，改變飛灰粉體的特性，並能使飛灰中的重金屬穩定化不易溶出。
本研究使用反應灰探討水萃處理及研磨程序的搭配，對於飛灰中重金屬穩定化的效果。另使用鍋爐灰與反應灰混合而成的混合灰作為材料，經水萃處理後，使用乙醇、水、0.2 M/0.02 M磷酸溶液為助磨劑探討濕式研磨穩定重金屬現象，並進行研磨穩定效率之評估。其中並以高量添加氧化鉛，以利處理成效之觀察。
由實驗結果得知，飛灰經由水萃程序能夠萃出飛灰中可溶性的元素，如:鉛、鈣、鈉、鉀，氯等元素。飛灰經由先水萃處理後研磨程序，在研磨1小時會使飛灰內的重金屬穩定化而不易溶出。僅經研磨或先研磨後水萃程序對於重金屬鉛的穩定，則需要長時間的研磨才能有效果。由高量添加氧化鉛的實驗中，使用乙醇及0.2M磷酸為助磨劑，在研磨1小時研磨穩定效率可達90%，此實驗証實了濕式研磨具有優異的穩定重金屬功能。

關鍵字

飛灰 ； 水萃 ； 研磨 ； 重金屬 ； 磷酸 ； 穩定

並列摘要

Municipal solid waste incinerator (MSWI) ashes have already been considered to recovery and reuse. However, due to the contaminants of dioxins, heavy metals and salts that are enriched in fly ash, it is difficult to be processed due to the heavy metals leaching and chloride dissolution problems. According to the references, mechanical energy which induced by wet-ball-milling could alter the characteristic of particles and transform the heavy metals into more stable status, it is possible to be applied in the stabilization of MSWI fly ash.
In the study, one of the experiments used the reaction product of fly ash as the sample to compare the different effect of heavy metals stabilization between two processes, milled milling water-extraction-ball-milling and ball-milling-water-extraction. The second part of the experiments used mixed fly ash made by boiler ash and reaction product of fly ash as the sample. The mixed fly ash was first processed with water-extraction and then added plenty of lead oxide to enlarge the effect of the treatment. Ethanol, water, 0.2 M and 0.02 M phosphoric acid solution were used for the milling aid respectively to explore the effect of stabilization.
The results shown that water-extraction could extract large amount of soluble element such as Pb, Ca, Na, K and Cl etc. from the fly ash. The lead was faster subjected to stable phase in the water-extraction ball- milling process within only 1 h of milling operation. However, the contrary process, ball-milling-water-extraction, need longer milling time to reach the same effect. The stabilization efficiency could reach 90% only after 1 h of milling when used ethanol and 0.2 M phosphoric acid as the milling aid in the condition of lead added. The results shown that wet ball milling do has effect on stabilization of heavy metals in the fly ash.

並列關鍵字

MSWI fly ash ； heavy metals ； stabilize ； water extraction ； ball milling.

參考文獻

何鴻哲，「垃圾焚化飛灰中揮發性重金屬之移動特性」，淡江大學水資源及環境工程研究所，博士論文，2008。

莊家榮，「濕式研磨對MSWI飛灰特性影響之研究」，碩士論文，淡江大學水資源及環境工程研究所碩士論文，2006。

黃彥為，「高能球磨飛灰內重金屬在高溫環境下穩定之研究」，碩士論文，淡江大學水資源及環境工程研究所碩士論文，2008。

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