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年度	106	專案性質	實驗性質
專案類別	模場試驗	研究主題	整治
申請機構	國立中興大學	申請系所	環境工程系所
專案主持人	張書奇	職等/職稱	副教授
專案中文名稱	二仁溪污染底泥整治模場試驗計劃(結合相反轉法與再利用加蓋法技術研發)
中文關鍵字	底泥整治,二仁溪,模場試驗,相反轉法,底泥加蓋
專案英文名稱	Remediation pilot study of the contaminated sediments in Er-Ren River (technology development of coupling phase inversion temperature and active capping using cleaned-up sediments)
英文關鍵字	Remediation of sediments, Er-Ren River, Phase inversion temperature, Sediment capping
執行金額	2,100,000元
執行期間	2017/1/9 至 2017/11/30
計畫中文摘要	台灣地區之底泥污染情況相當嚴重，多項疏水性有機污染物以及重金屬污染監測濃度在全世界之監測濃度均名列前茅，如中國石油化學工業開發(股)公司台南安順場址海水池底泥中之戴奧辛、五氯酚與汞以及二仁溪底泥中之PCBs、多溴聯苯醚、多環芳香烴類、聯苯二甲酸酯類塑化劑以及重金屬等。由於部分污染物之監測濃度已經屢次超過法規規範值，且因絕大部分污染物是附著於較小粒徑之底泥顆粒，在水體經過反覆擾動後再沉降之過程中，小粒徑底泥顆粒之沉降速度明顯較慢，故容易沉積於淺層底泥，且容易為底棲生物與浮游生物所接觸與攝食，且因這些疏水性鹵化有機物不易代謝降解，一旦進入生物體內將導致食物鏈中污染物隨營養層次向上傳遞而形成生物放大（biomagnification）現象，損害生態系與人體健康福祉。為有效去除表層底泥中之疏水性鹵化有機污染物，本研究主要應用四項技術及污染物之物化特性進行疏水性氯化有機物污染底泥整治技術研發，即(1)利用高溫之水在油中乳化液進入孔隙中直接接觸疏水性有機污染物增加接觸機會，藉著高溫使污染物之脫附與擴散加快之特性可將其有效傳輸至油相中；(2)再利用上層底泥造成降溫完成相反轉與形成超小油顆粒之技術，快速有效地將污染物傳輸至底泥上方以去除污染物；(3)利用已經完成整治並達標之淺層底泥作為現成加蓋材料，進行直接壓實之生物主動式加蓋（Bioacitve capping）；(4)於完成加蓋後，可利用下方底泥中經過熱篩而佔優勢之產氫微生物成為優勢菌群進行殘餘乳化液之發酵產氫，上方底泥中之厭氧還原脫鹵菌群利用氫氣進行有效且持續之生物降解作用，將由下層底泥中擴散進入上層底泥之鹵化污染物持續降解，形成有效之主動式生物屏障（active biobarrier）。本計畫原本為2年期計畫之第2年計畫，截至目前為止，符合進度要求，初步結論為歷年來二仁溪匯流處PCBs濃度似乎未見降低，不同深度樣品中有73%超出底泥品質指標下限值；相反轉單次操作可回收約62%之風化之Aroclor 1254，風化污染物組之回收去除程度明顯優於添加污染物組，可能與乳化液現地相反轉可大幅提高與風化之疏水性有機污染物接觸所致，且高溫可能極有助於污染物之質傳，HCB整體去除及降解情況均優於Aroclor 1254。無論HCB或是Aroclor1254，只要是風化之污染物，以現地相反轉乳化液回收結合生物分解可以達到98%以上之整體去除率，此可能為文獻中最佳之結果。本研究之結果應可確認此技術在遭受疏水性有機物污染底泥之現地整治具有高度可行性。
計畫英文摘要	Sediment contamination in Taiwan is an imperative environmental problem. Concentration levels of some hydrophobic organic compounds (HOCs) and heavy metals are ranked at the front all over the world. For example, the sediments in a seawater lagoon at An-Sun site in Tainan is heavily contaminated by dioxin, pentachlorophenol, and mercury while the sediment in Er-Ren River is highly contaminated by polychlorinated biphenyls, polybrominated diphenyl ethers, phthalate esters, polycyclic aromatic hydrocarbons, and heavy metals. Monitoring results often showed that some HOCs already exceeded the regulated levels. These HOCs easily accumulated at the surface sediment because finer particles tend to deposit on top of the sediments and they offer larger surface area for HOCs to adsorb on. Thus, HOCs are easy for benthic organisms to access and uptake and can be biomagnified through trophic levels. At the end, these HOCs would affect ecosystem integrity and human health. To remove HOCs in shallow sediments, we proposed a study to employ four technologies and the inherent properties of HOCs. Major mechanisms are as follows: (1) higher contact opportunity between hot water-in-oil emulsion and HOCs in sediments, (2) more efficient desorption and diffusion of HOCs at higher temperature, (3) phase inversion at the cooler upper region of sediments to facilitate oil droplet transportation in pores, (4) utilization of the cleaned sediment material as an active capping materials,(5) higher hydrogen generation rate at the heat-treated lower region of the sediment, and (6) enhanced reductive dechlorination of halorespirers at the upper region of the sediments. This study has shown that single inverse phase operation can remove 62% of weathered Aroclor 1254 and the the following biodegradation generally is decreasing. For weather HCB and Aroclor1254, the overall removal could reach higher than 98% in 70 days. These results strongly support that this new technology has high feasibility to be implemented in full-scale field remediation.