跳到主要內容 :::

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	國立中山大學	申請系所	環境工程研究所
專案主持人	高志明	職等/職稱	西灣講座
專案中文名稱	開發電催化及微氣泡整治系統處理 油污染土壤及地下水：現地模場試驗
中文關鍵字	電催化水、總石油碳氫化合物、土壤污染、氫氧自由基
專案英文名稱	Development of electrocatalytic and microbubble remediation system treatment Oil contaminated soil and groundwater: local model field test
英文關鍵字	Electrocatalytic water, total petroleum hydrocarbons, soil pollution, hydroxyl radicals
執行金額	1,600,000元
執行期間	2021/2/24 至 2022/2/28
計畫中文摘要	石油碳氫化合物(petroleum hydrocarbon)對土壤和地下水供應的污染是一個嚴重而普遍的環境問題。人們越來越重視開發創新技術來清除這種污染，成本高、效率高。這項擬議研究的目的是評估應用納米電解催化水(nano-electrolyzed catalytic water, NECW)通過化學氧化和納米氣泡過程修復石油-烴污染土壤的潛力。NECW可以改變水分子結構，通過電解催化和電解過程產生鹼性和酸性水。開發的EC系統利用直流電施加高壓和高電場來改變水分子的結構。催化電極之間在高壓作用下的放電、電極之間鋪設的催化劑增強的EC以及電解反應可以產生用於有機污染物氧化的電解催化水(electrolyzed catalytic water, ECW)。通過在電極之間鋪設獨特的離子分離膜，還可以生產氧化水和酸性水(pH 5)以及還原水和鹼性水(pH 10)，以供進一步應用。ECW包含不同類型的離子和自由基，包括羥基自由基(·OH)，它是最具反應性的自由基，可用於總石油碳氫化合物(total petroleum hydrocarbon, TPH)的氧化。我們團隊研發的創新催化劑，可以有效提高羥基自由基的生產效率。此外，在EC過程中產生的納米氣泡可以在ECW中存在更長的時間，並且它們在破裂後可以連續產生羥基自由基。產生的自由基還可以增強TPH的氧化機制。因此，可以獲得長期的羥基自由基產生和持續的污染物氧化效率。我們的研究團隊完成了以下任務：ECW系統設計、創新催化劑生產和ECW原型開發。通過一系列批量 EC 和氧化測試、柱研究和反應器實驗，建立了EC系統和納米氣泡的反應和理論以及用於現場規模應用的參數。該原型已成功應用於位於高雄市的 TPH 污染加油站，用於土壤和地下水淨化。 電子順磁共振(EPR)分析結果表明，NECW含有·OH，其濃度高於未催化的帶狀水。這表明電解催化體係可以有效提高·OH的生產效率。在這項研究中，羅丹明B (RhB) 被用作檢測·OH 的探針。結果表明，NECW 中的·OH 濃度遠高於未催化自來水中的·OH 濃度。實驗結果表明，電催化水中的OH·濃度範圍為6.2×10-13～7.4×10-13 M，可以有效地進行TPH的氧化降解。 當RhB用作化學探針時，結果表明OH·濃度的增加與電流密度呈正相關。催化催化劑載體實驗結果表明，銅催化劑可在20 min內有效提高TPH降解效率，土壤中TPH濃度由27,868±818 mg/kg下降至5,170±140 mg/kg。 30 min後羥基自由基濃度增加到4.0×10-13 M，遠高於鐵為催化劑的濃度。結果表明，隨著催化劑的加入，電催化水中的羥基自由基顯著增加。此外，透過管柱模擬現地整治試驗結果得知TPH可有效地被氧化和降解，土壤TPH可達到80%的去除率，TPH濃度可降至1000 mg/kg以下（監管標準）。。結果還表明，處理後水相中的TPH也被完全去除，表明產生的羥基自由基可以有效降解水相中的TPH。 現地整治試驗結果得知，當使用催化劑時，土壤處理效率可達到TPH去除率的 85%。此外，還產生了鹼性水，表明在反應過程中產生了羥基自由基。根據研究結果，證實本研究開發的創新電催化水系統能夠有效處理TPH污染的土壤和地下水，並在短時間內達到修復的目標。使用電催化水進行現場修復只需要電力和EC設備。結果表明，EC系統的運行需要大約 240 kWh 的電力來修復一噸受污染的土壤。如果加上人力等其他相關成本，每噸污染土壤的修復成本約為新台幣1,500至2,500元，比傳統的化學氧化和熱處理低五至十倍。 所開發的EC系統可有效應用於修復不同環境條件下具有不同特性的有機化學污染介質。這項研究的結果將有助於開發一種創新且經濟的技術來處理 TPH 和其他有機化學污染的土壤和地下水。 關鍵字: 電催化、總石油碳氫化合物、土壤污染、氫氧自由基、奈米氣泡
計畫英文摘要	Contamination of soil and groundwater supplies by petroleum hydrocarbons is a serious and widespread environmental problem. Increased attention has been paid for developing innovative technology for cleaning up this contamination costly and efficiently. The objective of this proposed study was to evaluate the potential of applying nano-electrolyzed catalytic water (NECW) to remediate petroleum-hydrocarbon contaminated soils via the chemical oxidation and nanobubble processes. NECW can change the water molecular structure and produce the alkaline and acidic water via the electrolyzed catalytic and electrolysis processes. The developed EC system applies high voltage and high electric field using direct current to change the structure of water molecular. The electric discharges between catalyzed electrodes under the activities of high voltage, enhanced EC by catalysts laid between electrodes, and electrolysis reactions can produce electrolyzed catalytic water (ECW) for organic contaminant oxidation. With a unique ion separation membrane laid between electrodes, oxidized and acidic water (pH 5) as well as reduced and alkaline water (pH 10) can be also produced for further application. The ECW contains different types of ions and radicals including hydroxyl radicals (·OH), which is the most reactive radical and it can be used for organic contaminant [e.g., total petroleum hydrocarbon (TPH)] oxidation. The innovative catalysts developed by our team can effectively improve the production efficiency of hydroxyl radicals. Moreover, the nanobubbles produced during the EC process can exist in the ECW for a longer period of time and they could produce hydroxyl radicals continuously after bursting. The produced radicals can also enhance the TPH oxidation mechanism. Thus, a long-term hydroxyl radical production and continuous contaminant oxidation efficiency can be obtained. Our research team has completed the following tasks: design of the ECW system, innovative catalyst production, and ECW prototype development. The reactions and theories of the EC system and nanobubbles and parameters used for field-scale application have been established via a series of batch EC and oxidation tests, column studies, and reactor experiments. The prototype has been successfully applied at a TPH-contaminated gas station site located in Kaohsiung City for soil and groundwater cleanup. Results from the electron paramagnetic resonance (EPR) analysis show that the NECW contained ·OH and its concentration was higher than that of uncatalyzed tape water. This indicates that the electrolyzed catalytic system could effectively improve the efficiency of ·OH production. In this study, rhodamine B (RhB) was used as a probe for ·OH detection. Results show that the ·OH concentrations in NECW were much higher than the ·OH concentrations in uncatalyzed tape water. The experimental results show that the OH· concentrations in the electrocatalytic water ranged from 6.2×10-13 to 7.4×10-13 M, which could effectively carry out the oxidative degradation of TPH. When the RhB was used as a chemical probe, results show that the increased OH· concentrations had a positive correlation with the current density. The results of the catalytic catalyst carrier experiment show that the copper catalyst could effectively improve the TPH degradation efficiency within 20 min, and the TPH concentration in the soils dropped from 27,868±818 mg/kg to 5,170±140 mg/kg. The concentration of hydroxyl radicals increased to 4.0×10-13 M after 30 min, which was much higher than that using iron as the catalyst. Results indicate that the hydroxyl radicals in the electrocatalytic water had a significant increase with the addition of catalysts. Moreover, results show that TPH can be effectively oxidized and degraded, and more than 80% of TPH could be obtained. Results also show that the TPH in the water phase was also completely removed after the treatment process, indicating that the produced hydroxyl radicals could effectively degrade the TPH in the water phase. The results of the pilot-scale study show that the soil treatment efficiency was around 80%, and the TPH concentration could be reduced to below 1,000 mg/kg (regulatory standard). The results of the pilot-scale study also show that the soil treatment efficiency could reach 85% of TPH removal when catalysts were applied. Moreover, the alkaline water was also produced, indicating that the hydroxyl radicals were generated during the reaction. According to the results of the pilot-scale study, results confirmed that the innovative electrocatalytic water system developed by this study could effectively treat the soil and groundwater polluted by TPH, and achieve the goal of remediation in a short period of time. The use of electrocatalytic water for field remediation only requires electricity and the EC equipment. Results show that approximately 240 kWh of electricity was required for the operation of the EC system to remediate one ton of polluted soils. If we included the other related costs such as man power, the remediation cost for each ton of contaminated soil was around NT$1,500 to 2,500, which is five to ten times lower than that of conventional chemical oxidation and thermal treatment. The developed EC system can be effectively applied to remediate organic chemical contaminated media under different environmental conditions. Results from this study will be useful in developing an innovative and economic technology for the treatment of TPH and other organic-chemical contaminated soils and groundwater. Keyword: Electrocatalysis, Total petroleum hydrocarbons, Soil contamination, Hydroxyl radical, Nanobubble