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年度	100	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	國立中興大學	申請系所	環境工程系
專案主持人	梁振儒	職等/職稱	教授
專案中文名稱	柴油污染土壤之快速整治-石灰水合反應結合現地過硫酸鹽化學氧化處理技術評估
中文關鍵字	柴油、化學氧化法、活化過硫酸鹽、石灰、總石油碳氫化合物
專案英文名稱
英文關鍵字	diesel, chemical oxidation, persulfate activation, lime, TPH
執行金額
執行期間	2011/11/26 至 2012/11/25
計畫中文摘要	油品洩漏導致之土壤及地下水污染，對環境及人體健康造成潛在之危害，因 此，尋求對於油品污染之土壤及地下水整治復育技術為一值得探究之主題。現地 化學氧化法(ISCO)為一項快速整治污染土壤及地下水之處理技術，過硫酸鈉 (NaS2O8, SPS)氧化劑經由適當之活化程序(熱、金屬、鹼或過氧化氫活化)可有效 生成硫酸根自由基(SO4 -∙)或氫氧根自由基(HO∙)強氧化劑之反應環境，藉此提升氧 化破壞污染物之能力。本計畫嘗試利用石灰(CaO)之水合反應以提供熱能及鹼性條 件，活化過硫酸鹽之氧化程序，對於處理高碳數油品污染(例如：柴油)之可行性 進行評估。 結果顯示CaO 的添加所造成之熱(~80oC)及鹼性條件(pH>12)，無法有效活化 過硫酸鹽處理柴油污染，約達43%之柴油移除率，若僅以NaOH 活化(pH 13)及熱 活化(50oC)反應7 天，分別造成約15%及20%之柴油降解，得知CaO 水合反應結 合過硫酸鹽氧化程序尚未能造成完全之柴油降解成效。進一步由其他活化過硫酸 鹽氧化程序處理柴油污染土壤之試驗結果顯示，SPS/H2O2 及SPS/Fe2+系統為較佳 之反應程序，且提高二價鐵及過氧化氫濃度可有效提高柴油之降解成效，反應一 天即可達約60%移除率，然而較高濃度之過硫酸鹽並無法提升鐵活化處理柴油之 效率，但於SPS/ H2O2 之反應系統，較多之過硫酸鹽參與反應則造成柴油降解明 顯提升。此外，SPS/Fe2+系統中，若調整提高螯合劑濃度控制Fe2+活化過硫酸鹽 之反應條件下，於反應1 天後，可有效增加柴油污染物之降解達90%以上，大幅 降低柴油之污染濃度，反應後續添加CaO 與土壤進行拌混，可調整土壤pH，避 免氧化過後之所產生之酸性pH，依據CaO 水合生成Ca(OH)2 所造成之土壤重量 增加，可使柴油濃度稀釋降至法規標準值以下。此外，高濃度螯合劑螯合鐵活化 之組別除可達到較高之柴油移除效率外，相較於H2O2 活化處理成本亦較低，估 算結果顯示，其螯合鐵活化程序每頓污染土所需之藥劑費用介於$1,200-$1,400 間， 處理後之土壤若添加5%之CaO 予以混拌，每噸土處理費用則需額外增加約 $100。
計畫英文摘要	The oil-contaminated soil and groundwater poses significant environmental impact and hazard to human health. Therefore, it has been the subject of considerable interest for developing efficient remediation technologies. In-situ chemical oxidation (ISCO) is receiving great interests of environmental engineers because it is capable of rapidly oxidizing organic contaminants. Among available oxidants, sodium persulfate (Na2S2O8, SPS) can be activated by several ways including heat, metals, alkaline and hydrogen peroxide to produce free radicals such as sulfate radical (SO4 -∙) and hydroxyl radical (HO∙). The generation of SO4 -∙and HO∙ could improve the efficiency of destruction of organic contaminants. The goal of this proposal was to investigate lime (CaO) hydration reaction by providing heat energy and alkaline condition to induce persulfate activation for the treatment of diesel-contaminated soils. The results showed that addition of CaO coupled with SPS cannot trigger the effective diesel destruction (e.g., 43%) through the generated heat (~ 80oC) and alkaline pH (> 12). Compared with the resuls from the experiments of SPS/NaOH and heat (50oC)/SPS after 7 d reactions, ~15% and ~20% of diesel removals were achieved, respectively. Therefore, it can be seen that the CaO/SPS process may not be an effective way for treating diesel contaminated soils. Among all possible persulfate activation processes, SPS/H2O2 and SPS/Fe2+ appeared as the preferable options for treating diesel. Morever, evalated concentrations of ferrous ion and hydrgen peroxide could significantly enhance diesel degradation efficiency. Around 60% of diesel removal would be achieved with 1 day of reaction. With different persulfate concentrations, no obvious improvement of diesel removal was found with higer concentrations of SPS in the SPS/Fe2+ system. On the contray, it indicated that more persulfate involved in the SPS/H2O2 system and lead to the increase in diesel degradation. Additionally, when significantly increasing complexing agent concentration in regulating Fe2+, removal of diesel can be greatly improved to around 90% within one day reaction in the SPS/Fe2+ system. Afterwards, mixture of CaO and treated soils resulted in an increase in soil pH to avoid the concern of increasedsoil acidity by oxidation. The hydration product Ca(OH)2 may increase the overal weight of soils and dilute the diesel concentration to reduce the concentration to meet the regulation. With respect to cost of treatment, the procedure employing elevated complexing agent in the SPS/Fe2+ system exhibited a lower cost (e.g., comparing to the SPS/H2O2 system) at $1,200-1,400 per ton of soils. When CaO is added at 5% by weight to treated soils, additional $100 per ton of soils would be costed.