油脂及有機物皆為汙染水資源的主因，而現今市場的技術大部分耗時及高成本，如何快速且有效的去除為此研究之主要目標。本研究主要為分離乳化油水及降低電鍍廢水的化學需氧量，根據台灣107年公布之最新環保法規，化學需氧量需降至100 mg / L以下才達到放流水標準。本研究以超臨界二氧化碳逆流柱系統處理電鍍廢水及含油廢水，分別以不同的壓力、溫度、滯留時間下探討其化學需氧量移除效率及除油率，並透過重鉻酸鉀迴流法及卡爾費雪法來進行檢測。此外，本研究也探討帶入模擬軟體算出其量產化後的經濟技術成本分析以每天處理量250噸來計算，所得到的最低建議售價為1.12元(美金)，而投資回收期為1.29年，且相對於其他技術而言，此技術為更低成本、更高效率且更為環保。而此實驗流場也將與計算流體模擬軟體進行比對與驗證。

Wastewater treatment has been considered as a major cost not only for the industry but for the society. Current technologies in the market are mostly costly and time consuming. This study proposed a supercritical CO2 (SCCO2)-driven countercurrent system for separating the emulsified oil from water (case 1) and reducing the chemical oxygen demand (COD) from electroplating wastewater (case 2). The effects of the operating parameters such as temperature, pressure and residence time were discussed. In addition, the design of recycling CO2 was developed for saving the CO2 costs. For the consideration of commercialization, the process was scaled-up to 250 tonnes/day and the recommended processing fee was $1.12/tonne for the payback period of 1.29 year, through the process simulation and techno-economic analysis (TEA). Compared to current process, this technology obtains the advantages of low cost, high efficiency and most importantly, environmental friendly. This study also employed the technique of computational fluid dynamics (CFD) for predicting the flow behaviors between the feed (wastewater) and SC-CO2

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