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年度	109	專案性質	實驗性質
專案類別	研究專案	研究主題	整治
申請機構	國立臺灣大學	申請系所	生物環境系統工程學系
專案主持人	廖秀娟	職等/職稱	教授
專案中文名稱	結合臺灣現地分離嗜酸硫氧化菌及咖啡渣整治重金屬污染底泥之可行性
中文關鍵字	嗜酸硫氧化菌，咖啡渣，底泥，重金屬
專案英文名稱	-
英文關鍵字	-
執行金額	920,000元
執行期間	2020/1/1 至 2020/12/31
計畫中文摘要	重金屬污染為全球面臨的環境隱憂。河川底泥不僅為重金屬污染物之累積終點，亦為潛在的污染物釋出來源，最終可能危害水中生物或人體健康。由行政院環保署的歷年調查結果得知，臺灣許多重要的河川底泥含有不同程度的重金屬污染物，部分重金屬污染物甚至超過底泥品質指標上限值。為達成土壤及地下水資源之永續利用，改善臺灣河川底泥品質為重要的課題。然而現行整治技術受限於費用昂貴、所需時程長、技術尚未成熟及適用範圍等缺點。因此發展低成本、高效率且對環境友善之整治技術仍為重要的課題。本研究計畫透過瞭解結合生物淋洗法及生物吸附法整治重金屬污染底泥之可行性，期能建立符合經濟效益及有效之整治技術，協助降低河川底泥重金屬對環境之衝擊。 本研究計畫期末報告，依計畫內容已完成桃園老街溪與臺南二仁溪的底泥採樣，並以序列萃取法分析底泥中重金屬的化學形態分布。此外，也確定嗜酸硫氧化菌SV5的硫氧化功能，並進行現地底泥的生物淋洗試驗。經生物淋洗處理的底泥，則進一步以序列萃取法分析經生物淋洗後底泥中重金屬的化學形態分布之改變。研究結果顯示，老街溪與二仁溪底泥中含有多種重金屬，包括As、Cr、Cu、Ni、Pb與Zn總濃度超過底泥品質的下限或上限值，其中Cu、Ni與Zn為老街溪與二仁溪底泥最主要的污染物。此外研究結果發現，二仁溪底泥可能因嚴重污染，比起老街溪對SV5的硫氧化功能造成較明顯的抑制。生物淋洗試驗結果顯示，底泥中生物可獲性較高的Ni、Zn與Mn能夠被有效去除。 生物淋洗出的重金屬則進一步利用咖啡渣進行移除。本研究收集廢棄咖啡渣，首先以模擬生物淋洗液探討咖啡渣對Ni、Zn與Mn的管柱吸附特性，並利用Thomas model擬合吸附曲線，計算出吸附能力q、吸附常數KTh等關鍵參數。由於生物淋洗液中也有一定濃度的Cu、Al與Fe，因此被納入試驗考量。在參數建立的過程中也發現Al對咖啡渣的重金屬吸附能力有負面影響。因此進一步利用Thomas model與上述參數推算固定條件下達到80%重金屬移除率所需咖啡渣量，並以現地底泥淋洗液進行生物吸附試驗，發現咖啡渣對老街溪與二仁溪現地底泥的Cu、Ni、Zn、Fe與Al具有穩定吸附能力，移除率達90%以上。此外咖啡渣對Mn的移除效率會受Al與Fe的影響，因此移除效率不穩定。綜上所述，本研究利用咖啡渣處理現地底泥生物淋洗液，可有效移除重金屬，未來可望以Thomas model為基礎提供有用的參數進一步嘗試將咖啡渣應用於實務操作。 本專案計畫期末報告內容符合預期執行進度，期望本研究計畫之成果，未來有助於推動生物整治在重金屬汙染底泥整治的實務方法應用。
計畫英文摘要	Heavy metal pollution is a global environmental concern. Sediment is not only the ultimate sink for heavy metal pollutants, but also the potential source for the re-release of pollutants, thereby posing potential risks to aquatic organisms or human health. Recent EPA reports have shown that various levels of heavy metal pollutants contaminated several major rivers sediments in Taiwan and some heavy metal contaminants exceeded the upper limits of sediment quality guideline. In order to sustain the use of soil and groundwater resources, it is important to improve the quality of sediments for the rivers in Taiwan. However, there are several limitations for current remediation technologies, including high cost, long process time, unrefined technology, and limited applications. Therefore, development of a low cost, high efficiency, and environment friendly remediation technologies is an important issue. Hence, this research aims to develop a cost-effective bioremediation strategy based on bioleaching and biosorption technique in order to mediate sediment heavy metals pollution, thereby decreasing the ecological impacts posed by heavy metals. In this final report, we have collected sediment samples from Laojie river and Erren river. Heavy metals in the sediment samples were analyzed using a 4-step sequential extraction procedure. In addition, the activity of the in situ isolated acidophilic sulfur-oxidizing bacterium, SV5 was confirmed before proceeding to bioleaching for the sediments. Subsequently, the residual heavy metals in the sediments were analyzed using the 4-step sequential extraction procedure. The results showed that sediment samples from Laojie river and Erren river contain multiple heavy metals and concentrations of As, Cu, Cr, Ni, Pb and Zn exceed the lower or upper limits of sediment quality guideline. In addition, Cu, Ni, and Zn were identified as major pollutants in sediments from both Laojie river and Erren river. Moreover, comparing with Laojie river, a more significant inhibition of SV5 sulfur-oxiding activity was observed in Erren sediment. This suggests that more severe heavy metal pollution in Erren river. Futhermore, bioleaching procedure using SV5 effectively removed the bioavailable fraction of Cd, Ni, Zn, and Mn from the sediments. Furthermore, heavy metals in the bioleachate were further removed by spent coffee ground (SCG). We collected SCG and initially assessed the fixed-bed column sorption capacity of SCG to Mn、Ni and Zn using simulated wastewater. Cu, Al and Fe were taken into account due to their existence in the bioleachate. The sorption kinetics of SCG in fixed-bed column was fitted by Thomas model, generating important parameters including q (sorption capacity) and KTh (Thomas sorption constant). We found that Al in the solution adversely affected the sorption capacity of SCG. Therefore, we initially estimated the required amount of SCG for heavy metal removal of 80% based on Thomas model. The results showed that removal of Cu, Ni, Zn, Fe and Al from the bioleachate was above 90%, which exceeded the original targeted 80% removal. In addition, we found that the removal efficiency of Mn was unstable due to the effects of Al and Fe. Taken together, results from this study showed that SCG is able to successfully remove heavy metals from the bioleachate in sediment and Thomas model provides useful paramaters for further application of SCG in practical pollution treatment. In this final report, we have fulfilled the progress as proposed in the grant proposal. We anticipate the findings from this research would make contribution to the development of practically feasible bioremediation strategy for heavy metals contaminated sediment.