焚化底渣再利用於道路工程之長期環境監測

The Environmental Monitoring of a Road Application with Incineration Bottom Ash

盧宥宇(Yo-Yu Lu)

指導教授 ： 童心欣

國立臺灣大學/工學院/環境工程學研究所/碩士(2008年)

https://doi.org/10.6342/NTU.2008.01459

摘要

在台灣都市焚化廠每年約排放將近90萬噸的焚化底渣，底渣再利用逐漸取代傳統底渣掩埋處理。底渣資源化途徑中，以底渣作為道路骨材配比再利用方式，所需要的技術及處理成本是最低的，在世界各地也廣泛被利用，且國內外道路現場案例研究中，皆屬無對環境負面影響。本研究針對台灣台北縣萬里鄉的路基含有底渣配比的試驗道路進行現場及實驗室相關研究。其目標除了重金屬，同時也針對總有機氯進行分析，有機氯是包含近年來發現底渣中含有致癌¬性物質也是持久性有機污染物(Persistent organic pollutants, POPs)重要的組成之一。本研究建立總有機氯檢測方法並應用在道路場址上外，並針對當地土壤與底渣滲出水進行研究探討是否因底渣含有大量氯鹽在經過土壤後衍生成有機氯污染物。
萬里道路監測結果發現雖底渣骨材存已離鋪設完工兩年半，但經過分析尚存在重金屬溶出現象，其中以鋇及銅溶出現象最為明顯。且針對排水瀝青表層鋪面測量其滲透性後進行監測期間溶出總量分析，96年8月起至97年2月底約有0.133(毫克/公斤-底渣)其次為銅0.047(毫克/公斤-底渣)溶出至環境內，而有機氯則無溶出現象。參照此場址剛完工至完工兩年期間監測結果中發現重金屬鉻、鉛、鎘及砷在底渣骨材溶出濃度有降低之趨勢。原始底渣在30公升淋洗下，重金屬中鋇、鉛、銅有明顯的大量溶出，其中以鋇的溶出量最大約為70 mg/kg、鉛約為21 mg/L及銅約為20 mg/L。總有機鹵素因pH值有明顯差異、以pH 3及pH 7在30公升淋洗後溶出量較多約為35 mg/kg。經過計算30公升淋洗量約等於場址完工至今的降雨量，因此在管柱重金屬溶出總量數據對近期現場具有相當代表性。場址土壤及底渣淋洗液培養結果顯示15天及30天皆有額外的有機氯物種產生，且推測可能氯鹽跟有機物反應衍生或由底渣溶出的多環含氯有機物的降解所產生的。

關鍵字

焚化底渣 ； 道路 ； 有機氯 ； 重金屬 ； 溶出

並列摘要

In Taiwan, approximately 900 thousand tons of bottom ash produced form municipal solid waste incinerator (MSWI) each year. The application of bottom ash as the road pavement is widely used around the world. The environmental impact on these applications were unclear. In our study, laboratory experiments and on site monitoring were conducted in Wanli Township, Taipei Country. Heavy metals and organic halides (TOX) were monitored form the experimental site.
The results showed that heavy metals leaching form the road site which was constructed 2.5 years ago, especially for copper and barium. Form August 2007 to the end of February 2008, about 0.133 mg-Ba/kg-ash and 0.047 mg-Cu/kg-ash was from the site. Compare the results form previous years, the concentrations of Cr, Pb, Cd and As were decreasing gradually. In column tests, bottom ash leached about 70 mg-Ba/L, 21 mg-Pb/L and 20 mg-Cu/L after washing with 30 liters of buffer. The pH value of washed buffer affects the leaching of total organic chloride, it approximately 35 mg/kg of TOX by using pH 3 and pH 7 washing buffer. The 30 liters of washing buffer volume in column test was equilibrant to three years of rainfall in Wanli Township. Some species of organic chloride were produced by the incubation of washing buffer and on-site soil. It is possible that chloride leached form incineration bottom ash could react with organic matter in the soil.

並列關鍵字

incinerator bottom ash ； road ； organic chloride ； heavy metal ； leaching

參考文獻

劉彥均, 2004. 以逐步萃取程序及溶出試驗評估都市垃圾焚化底渣長期穩定特性之研究. 國立台灣大學環境工程學研究所碩士論文.

Abbas, Z., Moghaddam, A.P., Steenari, B.-M., 2003. Release of salts from municipal solid waste combustion residues. Waste Management 23, 291-305.

Åberg, A., Kumpiene, J., Ecke, H., 2006. Evaluation and prediction of emissions from a road built with bottom ash from municipal solid waste incineration (MSWI). Science of The Total Environment 355, 1-12.

Bhattacharya, S.C., Abdul Salam, P., Sharma, M., 2000. Emissions from biomass energy use in some selected Asian countries. Energy 25, 169-188.

Bouvet, M., Franc¸ois, D., Schwartz, C., 2007. Road soil retention of Pb leached from MSWI bottom ash. Waste Management 27, 840-849.