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年度	109	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	國立高雄師範大學	申請系所	生物科技系
專案主持人	陳士賢	職等/職稱	教授
專案中文名稱	空蝕清洗結合臭氧之新穎技術整治污染土壤及底泥
中文關鍵字	土壤清洗, 空蝕清洗, 臭氧高級氧化技術, 石油探氫化合物污染土壤, 有機物污染底泥
專案英文名稱	Treatment of Petroleum Hydrocarbon Contaminated Soils and Sediments by Soil Washing with Cavitation Technique and Ozonation
英文關鍵字	Soil washing, cavitation micro jet shock wave, ozonation, Petroleum hydrocarbon contaminated soils, Organic contaminated sediments
執行金額	2,230,000元
執行期間	2020/1/1 至 2021/12/31
計畫中文摘要	本研究應用空蝕清洗結合臭氧高級氧化技術，開發新穎土壤清洗整治技術應用於污染土壤及底泥，其原理乃是利用空蝕(cavitation)現象，使清洗水在短時間經壓力變化而形成空蝕氣泡的生成與破滅，造成連續的破碎衝擊力量，並形成微米氣泡微觀物理衝擊效應，應用空蝕技術清洗單元，能連續取得空蝕氣泡破裂的瞬間高爆力、高壓力、高溫，作為破碎污染土壤之細小土壤團塊，清洗吸附於其上之殘留石油碳氫化合物，用於清洗吸附於細砂，極細砂甚至於坋土、黏土之附著油品，同時利用臭氧微米氣泡處理土壤清洗水中所殘留有機物，回收清洗用水，建立整治操作最佳條件，期望透過本研究所發展之離地土壤清洗整治技術，突破現有整治技術瓶頸，發展本土化且實際可行之整治技術。 本計畫以台灣南部某一大型石化污染場址進行研究，該場址為公告之整治場址，目前正進行整治工作，亦有相關土壤清洗設備供本模場計畫使用，污染物種類主要以石化污染物為主，場址原生土壤地質環境以砂質為主，地質分層在地表下約4至6 m為砂質坋土，其下有約1~2 m的細砂層；再向下則以中砂為主。進行模場試驗之土壤以現地原有潤滑油污染土壤為主，透過粒徑分析可得知其砂質高達92.91%，而將進入空蝕清洗流程之土壤佔46.15%。 在實場土壤清洗系統試運轉測試結果發現，油品污染土壤總石油碳氫化合物濃度範圍介於1500~12000 mg/kg之間，模場試驗於4月份以空氣進行空蝕清洗，空蝕清洗時間為10分鐘，潤滑油污染土壤經採用空氣空蝕清洗後，其總石油碳氫化合物(TPH)濃度約介於在1358 mg/kg至2424 mg/kg之間，移除效率約70.07~83.82%，而清洗用水經空蝕清洗污染土壤後，其化學需氧量(COD)增加3.6~16.2倍、總有機碳(TOC)增加6.3~8.3倍，綜合以上結果可證實空氣空蝕清洗運用於移除油品污染土壤中TPHd之效用。 6月中旬開始進行臭氧空蝕清洗試驗，至9月7日空蝕清洗試驗之臭氧添加量為12 L/min而清洗時間為15分鐘，臭氧空蝕清洗移除TPH之效率約在19.15~88.96%，而空氣空蝕清洗同樣清洗15分鐘之移除效率為31.11~83.15%，兩者效率差異不大。 自9月中開始增加臭氧添加量至20 L/min而清洗時間為20分鐘，所測得TPHd之移除效率為82.12~85.32%；而9月21日開始將臭氧添加量提升至24 L/min、清洗時間為20分鐘，所測得移除效率約在64.36~81.20%。顯然添加臭氧與空蝕技術對TPH移除率並未有具體顯著效果，甚至在四個批次試驗中，添加臭氧對TPH移除率反而比未添加者較差。因此由目前試驗結果得知臭氧添加量為20 L/min、清洗時間為20分鐘之移除效率較佳，但就目前試驗數據，欲比較添加臭氧與否對TPH移除率提升是否有幫助，可能需更多批次試驗，方能提供較明確方向。 針對清洗水之水質在空蝕清洗試驗之臭氧添加條件採12 L/min，清洗時間為15分鐘，清洗後之臭氧濃度維持在0.48 mg/L，將臭氧添加量提升至20 L/min，並延長清洗時間為20分鐘，清洗後之臭氧濃度維持在0.6 mg/L至0.72 mg/L，當臭氧添加量提升至24 L/min，清洗時間為清洗20分鐘，清洗後之臭氧濃度維持在0.90 mg/L至0.96 mg/L。 在本計畫中不論是空氣空蝕清洗潤滑油污染土壤或空氣空蝕結合臭氧清洗潤滑油污染土壤操作模式，使用後之清洗用水pH值維持在7.42~7.98之間，DO值維持在1.15~4.68 mg/L之間。在採用空氣空蝕清洗污染土壤後，TOC由4.3~6.0 mg/L增加為27.1~50.0 mg/L，在採用空氣空蝕結合臭氧清洗污染土壤後，依不同臭氧添加條件下，TOC由7.2~20.7 mg/L增加為12.1~31.1 mg/L，由2.9 mg/L增加為7.7 mg/L，由1.9~2.8 mg/L增加為8.0~27.7 mg/L。 在採用空氣空蝕清洗污染土壤後，清洗水中COD呈現顯著增加的狀態，COD由16.0~24.4 mg/L增加為87.9~260 mg/L，在多批次操作多數情況下，添加臭氧並未與水中COD作用，減少水中COD濃度。清洗廢水除CMS操作初期外，TPH濃度多能維持在10 mg/L以下，比較空氣空蝕清洗污染土壤之廢水，與空氣空蝕結合臭氧清洗污染土壤之廢水中，TPHd差距並不大，添加臭氧並未與水中TPH作用，達成減少水中TPH濃度，可能與清洗時間較短有關。 第二年工作預計將本技術運用於受有機物污染之土壤及底泥，預計工作項目由第一年模場試驗成果，修正及調整空蝕結合臭氧高級氧化技術操作參數，評估加入臭氧與未加臭氧時針對不同油品如汽油、柴油或燃料油污染土壤之處理效能，歸納污染底泥適合水洗粒徑範圍及污染底泥適合操作之污染濃度範圍及污染物移除率，評估空蝕清洗結合臭氧高級氧化技術其對有機污染物底泥整治效果及適用範圍。處理成本計算及操作參數最佳化，提出技術之適用性及限制性。
計畫英文摘要	Soil washing is a technique of concentrating contaminants through separation. It is a dynamic, physical process that cleans contaminated soil through transfer of the contaminant into a liquid stream. It does not destroy or immobilize the contaminants. Three mechanical washing methods such as jet reactor, attrition, and ultrasonic washing were commonly used on a laboratory scale. Consequently, the resulting concentrated soil must be disposed of carefully. Soil washing systems are used for soils contaminated with semivolatile organic compounds, fuels, and heavy metals. Adopting soil and groundwater remediation technologies such as soil washing to clean up petroleum hydrocarbon contaminated soils in the case that contaminated soil coupled with high sand content is considered as a fast and economical method. However, high organic content of the soil may require pretreatment and thus fully characterizing and understanding the site is of utmost importance. Wash water requires treatment before it can be discharged, as it is usually not completely free of smaller particles or organic particles. Soil washing processes for soil contaminated with volatile organic compounds may require emission controls. In order to facilitate the removal efficiency, certain physical and chemical processes will be incorporated. Given the above mentioned limitations, the promotion to obtain ultimate operation parameters and to improve the success of soil washing is proposed. The objective of this study was to evaluate treatment efficiency of the soil washing system in a petroleum hydrocarbon contaminated site. In particular, the technique of cavitation micro-jet shock wave (CMS) soil washing system was employed petroleum hydrocarbon contaminated soils. A two-year study was conducted in a petroleum hydrocarbon contaminated site which is located in Kaohsiung. The major tasks in the first year were to evaluate the removal efficiencies of total petroleum hydrocarbons (TPH) from contaminatd soils by CMS soil washing processes under various operation conditions. The first step was to use air-injected CMS soil washing system to treat lubricant contaminated soils. The cavitation cleaning time was set up at 10 minutes. TPH concentration ranged from 1500 mg/kg to 12000 mg/kg in the contaminated soils. After the cavitation, the concentration of TPH in the lubricant contaminated soil is about 1358 to 2424 mg/kg. The removal efficiency of TPH is about 70 to 83.2%. The ozone treatment was initiated in June to September 7, the ozone addition in the treatment was 12 L/min and the cavitation cleaning time was set up at 15 minutes. The removal efficiency of TPH was about 19 to 89%. At the same time, the removal efficiency of TPH with cavitation soil washing was about 31 to 83%. No enhanced removal of TPH was observed with ozonation. The ozone addition in the soil washing treatment was increased to 20 L/min and the cavitation cleaning time was set up at 20 minutes since September 15. The removal efficiency of TPH is about 82 to 85%. Since September 15, the ozone addition in the treatment was increased to 24 L/min and the cavitation cleaning time was still set up at 20 minutes. The removal efficiency of TPH is about 64 to 81.2%. Water quality paraters were monitored in the CMS system. The pH was maintained at 7.42 to 7.98 in the wastewater. Dissolved oxygen was at 1.15 mg/L to 4.68 mg/L. Apparent increase of TOC and COD was observed. After the cavitation washing, TOC in wastewater was increased to 27.1 to 50 mg/L and concentration of COD increased to 87.9-260 mg/L. While in the ozonation treatment system, TOC varied from 7.7 to 31.1 mg/L in the wastewater. Soil particle size and contamination level onto removal efficiency was examined. The operating parameters for each washing process were investigated in detail and mechanisms were proposed for the observed effects. Factors such as soils contaminated from different fuel types such as gasoline and diesel will be assessed in the second year. Treatment of organic contaminated sediments will also be the tasks in the second year. Contaminant extent and level, particle size in the sediment will be the focus. Addition of ozone to treat contaminated sediments will also be evaluated. Moreover, design and operation parameters for full-scale CMS soil washing will be suggested. It is anticipated the system can serve as an option of treatment train in soil and groundwater remediation technique.