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年度	110	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	國立高雄科技大學	申請系所	環境與安全衛生工程系
專案主持人	陳勝一	職等/職稱	教授
專案中文名稱	油品污染土壤超微氣泡清洗技術之開發
中文關鍵字	油品, 土壤, 超微氣泡, 清洗技術, 綠色科技
專案英文名稱	Remediation technology for oil-contaminated soils with ultra-fine bubbles
英文關鍵字	green technology, ultra-fine bubbles, soil washing, TPH
執行金額	800,000元
執行期間	2021/3/1 至 2022/2/28
計畫中文摘要	近年來由於油品洩漏或非法傾倒事件時有所聞因而導致土壤及地下水之污染日益嚴重，對於原本土地資源取得不易之台灣投資環境，無疑是雪上加霜，同時也對於環境與人體健康之潛在危害逐漸升高。土壤一旦受到污染，常需要花費數年乃至於數十年之功夫才能整治完成，而且必須投入極高之整治經費。一般而言，油品土壤之物化整治技術或多或少都有其實際應用上之限制，不外乎是處理效率不佳、成本高或是不符合綠色科技概念；而生物處理技術則有反應時間長之缺點。本計畫之目的主要是在研究應用創新超微氣泡清洗技術處理油品污染土壤之可行性，希望利用超微氣泡之高反應性、操作機動便利性及毒性副產物少等能力，優化及本土化油品污染土壤整治復育技術，藉由不同操作參數之影響探討，進行油品污染物自土壤中去除之最佳化；同時亦從反應動力學上，對於土壤中油品污染物去除學理上之探討，以對於油品污染土壤的整治復育有進一步之瞭解，並可以作為未來實際運用於污染土壤整治時之設計參考。 　　本計畫主要以含超微氣泡之清洗水自反應系統底部進流使土壤顆粒膨脹呈現流體化床之現象；此時，附著於土壤顆粒上之高黏滯力油品物質則因為超微氣泡爆裂所釋放之震波、能量及氫氧自由基而產生分離現象；最後再利用部分超微氣泡之浮除作用順利地將所分離的油品自水中去除。研究結果發現，超微氣泡產生器可以產生極佳之曝氣/曝氧速率，並且可以將水中溶氧快速提升至過飽和或超飽和狀態。另外，超微氣泡產生器將能有效延長曝氣後水中氣體之停留時間，此將有利於提升土壤中油污染物之去除效率。超微氣泡產生器確實可以有效生成高比例、高濃度及直徑大小分布較為集中之奈米級氣泡，其確實較傳統細氣泡曝氣盤更為微細，具有更大的接觸表面積，更長的停留時間。添加低劑量化學藥劑 (皂素或多元氯化鋁) 於超微氣泡土壤清洗程序中並無法明顯提升土壤中柴油之去除效率。氣泡爆裂釋放之氫氧自由基被確認為土壤中柴油去除的重要機制之一。在超微氣泡土壤清洗程序中，當土壤處理量越高時，土壤中柴油之去除效率會隨之降低；而當柴油濃度增加時，土壤中柴油之去除效率則呈現增高之趨勢。超微氣泡土壤清洗程序之最佳操作參數為土壤處理量 200 g/L、柴油濃度32,250 g/L時，土壤中柴油之最高去除效率達到81.5%。
計畫英文摘要	The soil pollution from oil spillage is a serious environmental problem, not only in the highly industrialized countries all over the world but also in Taiwan. A novel, green and environmentally-friendly technology is urgently required for the remediation of oil-contaminated soils in future. Due to the generation of shock wave and ·OH radical at the moment of bursting of ultra-fine bubbles in water, the bubble bursting energy can be subsequently applied to remove the oil pollutants from contaminated soils. Therefore, the purposes of this project are to develop an innovative soil washing technology for oil-contaminated soils with ultra-fine bubbles, and to investigate the applicability and efficiency of this soil washing technology for contaminated soil remediation by ultra-fine bubbles. In this novel soil washing technology, the up-flow washing water containing ultra-fine bubbles is firstly introduced into the reactor from the bottom, expansion of soil particles occurs during soil washing. Then the oil pollutants attached to soil particles are separated by several forces such as particle collision and friction, fluid shear stress, and bubble collapse energy. Additionally, the detached oils are floated from the wastewater to water surface during the soil washing. In this project, a soil washing process with ultra-fine bubbles for removal of diesel (TPH-d) from contaminated soil will be first established. In addition, the effects of process parameters and kinetics of diesel removal in this soil washing technology will be investigated. The size of ultra-fine bubbles will be also determined by nanoparticle tracking analysis (NTA). Finally, the treated soils will be evaluated for the feasibility of reuse and recycling. Based on the experimental results, it was found that high percentage (> 90%) and high concentration (2 x 10^7 #/mL) of ultra-fine bubbles generated in this study belonged to the nanobubbles with mean diameter of 58 nm. These ultra-fine bubbles also had higher dissolution rate of oxygen and longer retention time in water than microbubbles generated from traditional devices, which will be beneficial to the remediation of oil-contaminated soils. The removal efficiency of TPH-d from contaminated soils was not enhanced by adding low concentration (20 mg/L) of chemicals (saponin and polyaluminium chloride) in the soil washing process with ultra-fine bubbles. Free hydroxyl (-OH) radicals generation from collapsing ultra-fine bubbles was found to be the one of main mechanisms for TPH-d removal from the soils in the soil washing process with ultra-fine bubbles. The results showed that the removal efficiency of TPH-d increased with decreasing soil solids content and increasing TPH-d concentration in soil. The results of response surface methodology indicated that the maximum efficiency of TPH-d removal was achieved at 200 g/L of soil solids content with 32,250 mg/kg of TPH-d concentration in soil, where up to 81.5% of TPH-d were removed from the contaminated soil.