台灣地區有含砷地下水存在，根據台灣地區水質統計年報資料指出其部分區域的 含砷濃度為 0.100-0.612 mg/L，而國內的飲用水水質標準對於「砷」的管制為 0.01 mg/L 以下。一般淨水程序的混凝、沉澱、過濾等單元，對於「砷」的去除效果有限，雖然 以增加混凝劑加藥量來加強「砷」的去除，但亦導致加藥成本增加，也增加了污泥量 的產生。 於現場的操作中，氧化、混凝沉澱過濾常見的砷處理技術，除砷效率較高之技術 如薄膜過濾、離子交換及活性鋁等，但相對傳統技術而言卻是高處理成本，一些研究 指出利用鐵鹽混凝搭配微過濾方式顯示出最低的初設成本以及操作維護費用，可將含 砷初始濃度為 10~500 μg/L之含砷水樣處理至 10 μg/L以下。 本研究利用 PTFE材質之 MF膜搭配氯化鐵膠羽與淨水場污泥，建置一「膠羽薄 膜反應器」，利用含砷之模擬原水來進行試驗。評估氯化鐵混凝產生之膠羽與淨水場 鐵錳污泥於反應器之中砷的吸附效果，之後再評估此一反應器產生之污泥特性並進行 污泥燒結，再以毒性溶出試驗測試燒結體的砷溶出情形。 There are regions in Taiwan where the groundwater contains arsenic. According to data from the annual report of the Taiwan Regional Water Quality Statistics, groundwater from a few regions contain arsenic concentrations of 0.100–0.612 mg/L; the maximum contaminant level of arsenic for drinking water has been regulated below 0.01 mg/L by Taiwan EPA. In traditional water treatment process, generally used coagulation, precipitation, and filtration have a limited effect on arsenic removal. Although increasing the coagulant dosage can help to enhance the removal of arsenic, this also increases the amount and the costs of produced water treatment sludge. Although techniques such as membrane filtration, ion exchange and activated alumina have high arsenic-removal efficiencies, these techniques also tend to have relatively high treatment costs. Some studies showed that the pre-coagulation followed microfiltration (MF) was the most economical and effective method as it had the lowest initial set-up costs, as well as the lowest operating and maintenance costs. The literatures also showed that this technique was able to reduce initial arsenic concentrations of 10–500 μg/L to below 10 μg/L. In this study, MF membranes made of polytetrafluoroethylene (PTFE), combined with Ferric Chloride coagulation floc and drinking water treatment sludge, were used to set up the “Flocculation and Microfiltration Reactor (FMR)”, and tested using synthetic arsenite raw water. The study mainly assessed the efficiency of arsenite removal using FMR. The characteristics of sludge produced from FMR will be evaluated in this study. And, the arsenite leaching condition after sludge sintered also will be evaluated with TCLP test.
