跳到主要內容 :::

年度	107	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	國立中正大學	申請系所	地球與環境科學系
專案主持人	陳建易	職等/職稱	教授
專案中文名稱	微生物固定化之地下水除砷技術之研究
中文關鍵字	微生物固定化; 地下水; 砷
專案英文名稱	Arsenic Removal in Groundwater with Microbial Immobilization
英文關鍵字	Arsenic Removal , Groundwater , Arsenic
執行金額	697,500元
執行期間	2018/1/10 至 2018/11/30
計畫中文摘要	本計畫利用三座淨水廠之富含氯化鐵之污泥廢棄物製備輕質骨材(孔隙性陶粒)，公園、觸口和水上淨水場之陶粒經由燒製後粒徑大小分別為16-22mm、16-22mm和16-18mm，而孔徑大小分別為0.21-9.7 mm、0.22-6.68 mm和0.07-1.54 mm。利用輕質骨材作為微生物固定化基材，預期可以透過微生物氧化作用、氧化鐵吸附作用及微生物固化作用，達到含砷地下水的整治目的。透過實驗室規模的處理箱模型，探討孔隙性陶粒對於含砷水樣的砷吸附動力學模式。但期中實驗結果不如預期，當含砷地下水進入實驗模擬水箱反應後，可發現樣本中砷濃度不降反升，水樣中砷初使濃度為77.41 µg/L，放置72小時後砷濃度達105µg/L。懷疑是實驗中的陶粒或是細菌產生的反應與預期不符，因此期末報告中進行了數項檢測。在污泥吸附與溶出實驗中發現三座淨水廠陶粒皆會釋出砷離子，造成砷濃度上升，其中以公園陶粒砷釋出量最高，72小時後可達19.59 mg / kg。重金屬化學序列萃取實驗分析表明，實驗結果顯示砷的化學狀態在污泥中為穩定的鐵鎂氧化態和殘留物態，但經過高溫燒結後會轉換成不安定的離子交換態、碳酸鹽態和鐵鎂氧化態。此實驗結果證實了污泥吸附與溶出實驗的結果。微生物降解砷實驗中表明，B. pasteurii可以吸附砷離子，24小時後砷濃度從3.31 mg/kg下降至1.14 mg/kg有著大幅度的下降。本計畫執行的成果，包含新型陶粒吸附材料的開發與效能測試結果，作為含砷地下水的砷去除技術核心，以及陶粒砷脫附、再生與後續處理建議方案，也可作為地下水污染整治技術之參考。
計畫英文摘要	The aim of this project is to optimize the process for the synthesis of lightweight aggregates (porous ceramsites) from the ferric-rich clay waste of three water supply plants. The lightweight aggregates from Gong Yuan, Chu Kou, Shui Shang water supply plant, the particle size was 16-22mm, 16-22mm, 16-18mm, and pore size was 0.21-9.7 mm, 0.22-6.68 mm, 0.07-1.54 mm. The lightweight will be used as a substrate for microbial immobilization. It is expected that the porous ceramsite filled with ferric oxide / bacteria in the lightweight aggregate prepared in this project could achieve the remediation of arsenic-containing groundwater through microbial oxidation, iron oxide adsorption and microbial solidification. Through the laboratory-scale treatment box model, the kinetic model of adsorption of arsenic on porous arsenic-containing water samples. But the mid-term experiment results ware not as expected. When the arsenic-containing groundwater entered the treatment box model, we found the sample concentration of heavy metal arsenic was increased. The initial concentration of arsenic in the groundwater water sample was 77.41 μg/L, and the arsenic concentration was increased to 105 μg/L after 72 hours. The results didn’t square with the team’s expectations and it couldn’t discover why. Therefore, several experiments were carried out in the final report. Adsorption and dissolution experiment results indicated that the lightweight aggregate from three water supply plants were released arsenic ions. Among them, the Gong Yuan Water Supply Plant had the highest release of arsenic, and the arsenic concentration was increased to 19.59 mg / kg after 72 hours. Sequential extraction results indicated that the sludge chemical fractionation of arsenic was in the iron and manganese oxide-bound fraction and residual fraction. And the lightweight aggregate chemical fractionation of arsenic was in the oxide-bound fraction, carbonate-bound fraction and exchangeable or easily bioavailable fraction. Results showed that when sludge was converted into lightweight aggregate by high temperature sintering, the chemical fractionation of arsenic was changed. Microbial adsorption of arsenic experiment results indicated that Bacillus pasteurii could adsorb arsenic ions, the arsenic concentration was decreased from 3.31 mg/kg to 1.14 mg/kg after 24 hours. The implementation of this project includes the development and performance test results of the new ceramsite adsorbent material as the core of arsenic removal technology for arsenic-containing groundwater and the proposal of recycle, regeneration and follow-up of arsenic, which could also serve as an alternative for the treatment of groundwater pollution.