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年度	110	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	2,010,000元
執行期間	2021/2/24 至 2022/2/28
計畫中文摘要	本研究為應用空蝕清洗結合臭氧高級氧化兩種技術，開發新穎土壤清洗技術，應用於污染土壤及底泥整治，其原理乃是利用空蝕(cavitation)現象，使清洗水在短時間經由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，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，透過本研究所發展之離地土壤清洗整治技術，期望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為75.28%，而將進入空蝕清洗流程之土壤佔56.56%。 在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，模場試驗於第一年4月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，移除效率約介於70.07-83.82%，而經空蝕清洗污染土壤後清洗用水其化學需氧量(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。 2020年6月中旬開始進行臭氧空蝕清洗試驗，期間分別調整臭氧添加量或空蝕清洗時間，以尋找移除污染土壤TPH之最佳操作條件，由這一年半的試驗結果得知操作條件為臭氧添加量27 L/min、清洗時間為20分鐘之TPH移除效率較佳，其TPH移除效率約為84.29-91.92%。 檢視清洗用水水質，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7.12至7.97之間，DO值維持在3.01與6.30 mg/L之間。在採用空氣空蝕清洗污染土壤後，TOC明顯上升由1.30-20.7 mg/L增加為7.10-50.0 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分別由1.60-2.40 mg/L增加為8.00-35.2 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3.20-62.6 mg/L增加為18.9-260 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。清洗廢水除空蝕清洗系統建置操作初期外，廢水中TPH濃度多維持在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，TPH差距並不大，可能與清洗時間較短添加臭氧並未與水中TPH作用，達成減少水中TPH濃度。 由於不同油品污染土壤取得及運送入公告之污染場址較不易，後續沒有成功取得其他適合進行空蝕水洗試驗的油品污染土壤或底泥進行試驗，因此無法將本技術運用於其他污染油品進行成效比較。 本計畫以空蝕土壤清洗技術作為清洗油品污染土壤之方法，空蝕清洗系統無需另外增加清洗用水即可提高洗淨率；空蝕清洗時土壤混合泥水，可藉由所產生的微泡直接使含油之坋、黏土上浮，達到油水分離，無需另外添加藥劑來分離油污；而泥水以離心機脫水後，降低脫水污泥之含水率，廢水則進行處理後再循環利用。除了以上所述，本技術每日可處理約100噸污染土壤，每公噸污染土壤所需之花費3,238元，所需花費低於其他處理技術。本系統經數年操作可應用於大型石化污染場址，加速場址解除列管。
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. 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 soil washing system (CMS) was employed onto petroleum hydrocarbon contaminated soils. A two-year study is 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. Concentration of TPH 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, 2020. The recruitment of ozone or the cavitation cleaning time were adjusted to assess the best operating conditions for removing TPH from contaminated soils. The addition of ozone in the soil washing treatment was increased to 27 L/min and the cavitation cleaning time was 20 minutes. Currently this is the optimal operating condition for the past 18 months. Overall the removal efficiency of TPH was about 84 to 92%. Water quality paraters were monitored in the CMS system. The pH was maintained at 7.12 to 7.97 in the wastewater. Dissolved oxygen was at 3.01 mg/L to 6.30 mg/L. Apparent increase of TOC and COD was observed. After the cavitation washing, TOC in wastewater was increased to 7.10 to 50.0 mg/L and concentration of COD increased to 18.9-260 mg/L. While in the ozonation treatment system, TOC varied from 8.00 to 35.2 mg/L in the wastewater and concentration of COD increased to 25.4-116 mg/L. The study used the cavitation soil cleaning technology to clean up oil-contaminated soil. The CMS system does not require to add additional clean water to increase the contaminant removal rate; the soil was mixed with muddy water during cavitation cleaning, and the microbubbles generated can directly make oil-contaminated clay to float to achieve oil-water separation, without the addition of chemicals to separate the oil. The muddy water was dewatered by a centrifuge to reduce the moisture content of the dewatered sludge, and the water was treated and recycled. Overall, the cost of this technology for soil treatment is also lower than other treatment technologies.