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年度	108	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	環境工程學研究所
專案主持人	席行正	職等/職稱	正教授
專案中文名稱	利用混合式活性覆蓋材整治受多重重金屬污染底泥
中文關鍵字	活性覆蓋法,重金屬,底泥
專案英文名稱	Using mixed active capping to remediate multiple heavy metal contaminated sediment
英文關鍵字	active capping,heavy metal,sediment
執行金額	900,000元
執行期間	2019/1/10 至 2019/11/30
計畫中文摘要	人類在近數十年之工業化活動，使重金屬排放已經在全球造成嚴重的污染問題，我國亦有污染嚴重之底泥場址。底泥可視為有機物及無機物之匯集地，超過底泥品質標準限值之污染物往往是兩種以上，因此開發整治受多重重金屬污染底泥之技術有其必要性。依台灣101年度重點河川底泥污染檢測成果，本研究鎖定台灣常見重金屬污染底泥，關切重金屬以Cu，Cr，Zn，Ni和Hg進行研究。此類物質通常具有毒害性，經由接觸或攝入生物體內後，將導致生物體病變或死亡，且難以仰賴生物體之消化循環系統排除體外、或藉由微生物分解降低毒害性。透過食物鏈造成生物累積作用，將嚴重影響水域環境與生態系統之平衡。活性覆蓋法(active capping)為一具有經濟可行性之現地整治工法，能降低污染物釋出至水體中，進而降低人體健康與生態風險。本團隊在前期研究計畫中，發現以活性碳混合黏土礦物作為活性覆蓋層能有效抑制總汞以及甲基汞的釋出，而黏土礦物之性質對於覆蓋層的穩定性有一定的影響力。因此本團隊將致力於開發混合式活性覆蓋層，以整治受多重重金屬污染之底泥，並評估其可行性與穩定性。 本期研究主要分兩部分。第一部分為單一吸附材對單一重金屬之水相吸附批次實驗，以了解各吸附材對各重金屬之吸附能力並作為混合配比之評估依據。本研究之吸附材選用廢輪胎碳黑、硫化亞鐵、氫氧基磷灰石、高嶺土與製備氫氧基磷灰石的牡蠣殼粉，進行吸附重金屬 Cu，Cr，Zn，Ni和Hg。第二部分為利用改良自106年度模場試驗計畫之微環境系統，探討混合式活性覆蓋層對於抑制多重重金屬之能力與穩定性。此部分實驗將使用桃園灌溉渠道底泥(接續前期研究)進行人工培養，使底泥同時含有一定濃度之重金屬Cu，Cr，Zn，Ni和Hg。 第一部分的水相吸附實驗結果顯示，對於Cu，Cr，Zn和Ni來說，HAP與牡蠣殼粉總體而言呈現最佳的吸附效果，碳黑材料(CB)的吸附效果次之，FeS和kaolin的效果不明顯；而對於Hg來說，FeS和CB是最佳的吸附材料。在第二部分的擬環境混合式活性覆蓋層實驗中，我們可以看到以碳黑材料主要作為穩定汞的材料，HAP與shell合理分配比重的材料將會對整個擬環境系統的五種金屬及甲基汞的釋出起到最佳的抑制作用。本研究結果提供了一種以合理分配不同吸附材比重來達到多重污染環境治理的方法，更期望能進一步幫助國內底泥實場整治的實踐與應用。
計畫英文摘要	Over decades of human industrial activities, heavy metal wastewater has been discharged to river streams causing severe pollution problems across the globe. In Taiwan, there are also highly polluted sediment sites. Sediment can be seen as a sink of organic and inorganic compounds, often resulted in muti-pollutants with concentrations exceeding the limit of sediment quality guidelines. Due to high toxicity, non-biodegradability, biomagnification and bioaccumulation, heavy metals in sediment have been proved to pose a serious threat to the aquatic environment. Therefore, developing a remediation technology to treat multi-heavy metals sediment is necessary. In this project, we focus on understanding the effectiveness of using vairous adsorbents for capture of copper, chromium, nickel, zinc, and mercury present in sedment, which are five of major heavy metals according to the survey report of Taiwan in 2012 on main rivers with contaminated sediment. Additionally, active capping is an economically-feasible in-situ method for sediment remediation, reducing contaminants release from sediment to overlying water, subsequently reducing human health and ecological risks. Based on several previous research, active capping with AC/clay has been proven effective in reducing mercury and methylmercury species released to overlying water. Therefore, in this research, the feasibility and stability of capping multi-heavy metal contaminated sediment with mixed active caps are further evaluated. The proposed research can be divided into two parts. The first part is the aqueous batch experiments using five adsorbents to capture five heavy metals individually, in order to understand the adsorption affinity for each adsorbent. The capping materials include carbon black, kaolin, iron sulfide minerals (FeS), oyster shell and hydroxyapatite. The second part of the proposed research involves utilizing modified microcosms that were examined during the Year 2017 project to explore the multi-heavy metal inhibition and stability of mixed active caps. The sediment from irrigating canal in Taoyuan was collected then spiked with a fixed concentration of copper (Cu), chromium (Cr), nickel (Ni), zinc (Zn), and mercury (Hg). The adequate mixed active caps with repect to types and quantities were determined based on the aqueous batch experiments. Aqueous batch experiments in this research have revealed that HAP and oyster shell had the better affinity to Ni, Cr, Cu and Zn and carbon black took the third place. But towards Hg, FeS and CB played a more significant role in release inhibition. Results of operating the utilizing modified microcosms with composite materials showed that caps including CB could inhibit Hg and methylmercury better than FeS. Cheaper caps with more oyster shell powder couldn’t reach similar effects than the one with more HAP dealing with Ni and methylmercury. We expect that this technique could be further scaled up in remediation of domestic contamination sediment in actual sites.