跳到主要內容 :::

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	1,560,000元
執行期間	2020/1/10 至 2022/11/30
計畫中文摘要	土壤及地下水被石油碳氫化合物污染為一個普遍且嚴重的問題，總石油碳氫化合物(total petroleum hydrocarbon, TPH)污染來自於油品儲槽、管線老舊失修及操作管理不當等原因，導致油品外洩，其整治難度及整治經費均相當高。為加速油污染場址之整治，開發經濟有效的整治技術有其必要性。電催化水(electrolyzed catalytic water, ECW)設備利用電極間高電壓電場，經直流電場改變水分子的結構，經過高壓放電、電催化及電解作用，可快速產生鹼性還原水、酸性氧化水與中性水。電催化水系統陽極的氧化效果使水中氯離子與溶氧產生次氯酸(HClO)與超氧根離子(superoxide, O2-)，兩者互相作用下生成氫氧自由基。此外，帶電微氣泡逐漸於水中瓦解而釋出之能量與水分子作用亦產生暫態的氫氧自由基。本計畫之目的為開發創新電催化技術，以電催化技術產生之氫氧自由基及微氣泡整治TPH 污染之土壤及地下水；此外，本計畫以實驗室電催化及氧化試驗提供污染場址整治所需的參數，探討電催化水對TPH之去除機制及效率，並以現地模場試驗驗證電催化技術應用於實場整治之成效。本計畫亦以模場試驗成果評估利用電催化技術整治油污染場址的經濟效益。實驗室批次研究成果顯示，添加不同濃度電解質可有效提升氫氧自由基的濃度達6.2×10-13至7.4×10-13 M以及氧化還原電位(800-850 mV)，並加速TPH的氧化速率。本計畫以奈米粒子追蹤分析儀進行微氣泡分析，由分析結果可知ECW含有奈米氣泡(41-51 nm)，且氣泡濃度介於9.2×107至1.7×108 particles/mL且帶有較高的負界達電位，由於奈米氣泡的上升速度緩慢，因此帶電微氣泡緩慢瓦解所釋出與水分子作用產生暫態的OH·有助於水中TPH的降解。電子順磁共振(electron paramagnetic resonance, EPR)針對OH·定性分析的結果顯示，ECW具有高強度的自由基訊號。本計畫亦以羅丹明-B試劑(Rhodamine B, RhB)作為氧化能力指示劑，進行自由基濃度檢測。試驗結果得知電催化水中OH·濃度介於6.2×10-13至7.4×10-13 M，可有效進行TPH的氧化降解。由批次試驗結果可知， ECW可降解土壤約79.6 % TPH，可在短時間有效處理土壤TPH污染問題。本計畫選擇一處加油站污染場址進行現地模場試驗，並在該場址設置一口電催化水注入井以及三口下游監測井，評估電催化水灌注後對TPH污染地下水的處理效率。此外，亦在現場設置泥漿相反應槽，評估電催化水以離地的方式處理的TPH污染土壤的效率。評估結果顯示，土壤TPH濃度介於1,196至3,530 mg/kg，地下水TPH濃度介於40.14至19.46 mg/L，水力傳導係數為7.3×10-5 m/s，地下水流向由南向北流動。現地整治試驗結果得知，經過三個批次的電催化水處理，土壤TPH可達到80%的去除率，TPH濃度降低到1,000 mg/kg(法規標準)以下。地下水經過1.5噸(三倍孔隙體積)電催化水注入後，注入井TPH可達到62%的去除率，濃度已降低到10 mg/L(法規標準)以下。本計畫以模場離地整治試驗結果得知，污模場試驗的結果證實本計畫發展的創新電催化水系統可有效處理TPH污染的土壤和地下水，並在短時間內達到整治的目標。電催化水用於實場整治僅需花費電力及實場灌注設備，由模場試驗的結果可推算離地泥漿相每噸的污染土壤需使用240度電，現地淋洗灌注三次的耗電量為15.9度，若加上其他相關的花費，每噸污染土壤處理操作費用初估在1.5~2.5千元。本計畫將於第二年以觸媒的方式強化電催化系統的反應效果，並於實驗室批次實驗製備觸媒，並評估結合電催化系統最佳操作參數，並將此改良的電催化系統應用於模場試驗，評估技術放大的成效以及應用於實場整治的可行性。
計畫英文摘要	Contamination of soil and groundwater supplies by petroleum hydrocarbons is a severe and widespread environmental problem. Corrosion of storage tanks and poor sealing problems are usually the possible causes, which can cause leaks in storage tanks and pipes. Among those petroleum products, heavy-oil contaminated soils are more difficult to treat compared to more volatile petroleum products. Soil contamination with petroleum hydrocarbons has caused critical environmental and health defects. Increased attention has been paid for developing innovative technology for cleaning up this contamination costly and efficiently. The objective of this proposed study will evaluate the potential of applying electrolyzed catalytic water (ECW) to remediate heavy-oil contaminated soils via the chemical oxidation process. ECW can change the water molecular structure and produce the alkaline and acidic water via the electrolyzed catalytic and electrolysis processes. The ECW contains different types of radicals, including hydroxyl radicals (·OH), which can oxidize the petroleum hydrocarbons effectively. During the ECW oxidation study, the mechanisms causing the oxidation of total petroleum hydrocarbon (TPH) will be evaluated, and the results will be used to improve the oxidation efficiency of the ECW system. The advantages of this system include the following: no chemical oxidant addition, no pH adjustment, low operation, and maintenance cost, and high treatment efficiency. Moreover, the ECW also contains microbubbles or ultra-fine bubbles, which can produce ·OH continuously after bursting. The produced radical could also enhance the TPH oxidation mechanism. In the batch experiments, different electrolytes were added to evaluate the effectiveness of electrolyte addition on free radical production. Results show that the produced ECW was in neutral conditions (NECW), and the oxidation-reduction potential was around 800-850 mV. Results show that adding different concentrations of electrolytes can increase the concentration of hydroxyl radicals to 6.2×10-13 to 7.4×10-13 M.Results from the nanoparticle tracking analysis show that the ECW contained nano-scale bubbles (bubble diameter = 41-51 nm), and the bubble concentrations were in the range from 9.2×10 to 1.7×108 particles/mL. Results from the electron paramagnetic resonance (EPR) analysis show that the ECW contained ·OH and its concentration was higher than that in 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 ECW were in the range form 1.5×10-13 to 3.0×10-13 M, which were much higher than the ·OH concentrations in uncatalyzed tape water (2.8×10-15 to 7.4×10-15 M). Results from the batch oxidation experiments show that the approximately 37.5% of the TPH could be oxidized and 42.1% of the TPH could be removed from the soil phase to the water phase after the addition of NECW. This indicate that the mechanisms of TPH removal from the soils via the treatment of NECW included oxidation and desorption processes. Results from the column study show that the NECW could flow into the soil pores and remove the trapped TPH resulting a more complete soil remediation. A TPH-polluted site was selected as the target site pilot-scale study. One remediation well and three monitor wells were installed at this site. Results from the site investigation show that the soils were contaminated by TPH (1,196 to 3,530 mg/kg). The groundwater flow direction was from south to north with a hydrology conductivity of 7.3×10-5 m/s. Results of on-site remediation tests in the mold field show that the TPH pollution in the soil can be washed out through the electrocatalytic water, and the TPH pollution in the liquid can be removed by the electrocatalytic water with strong oxidizing power. After leaching three times, the TPH concentration in the overall well has a decreasing trend, and W1 is below 10 mg/L.According to the results of the on-site remediation tests in the model field, the TPH pollution in the soil is below 1000 mg/kg after stirring contaminated soil and electrocatalytic water.And the overall removal rate is as high as 80%, which confirms the electrocatalytic system It has a practical removal effect on the TPH pollution of the mode field. In this project, by adding a catalyst to the electrocatalytic system, using rhodamine B (RhB) as the chemical probe of ·OH in the measuring system, it is known that the ·OH concentration in the electrocatalytic water ranges from 6.2×10-13 to 7.4×10-13 M increased to 1.1×10-12 to 1.2×10-12 M. Based on the results of pilot-scale study, the cost for soil remediation using the developed ECW is in the range from NT$1,500 to 2,500 per ton of TPH polluted soils, which is much lower than the commonly used remedial technologies. In the second year of this project, the reaction effect of the electrocatalytic system will be increased by means of catalysts, and the optimal operational conditions and the processes for catalyst preparation will be studied via the laboratory batch tests. The results will be applied at the selected TPH-polluted site for performance evaluation.