整合式薄膜過濾系統回收化學機械研磨廢水之研究

Abstract

半導體產業為我國重要之高科技產業，其中晶圓廠之化學機械研磨 (CMP)製程為近年來 因技術改良、製程升級及擴廠等因素導致用水量劇增，而CMP 廢水中含有高表面電荷奈米 微粒及複雜之化學物質，所以不易處理，目前皆以水中懸浮顆粒為水質管制項目，但是CMP 廢水中顆粒皆為奈米顆粒，所以並不能完全適用此管制方法。科學園區管理處為此訂下水回 收規範，故發展低成本、節能與高效率的水處理與水回收技術將是值得挑戰的課題。 薄膜 (membrane)技術為一物理固、液分離技術，隨著科技不斷進步，薄膜的材質受到改 良價格也更為低廉，近年來相當大量的應用於污水處理、淨水工程、海水淡化等。與傳統處 理方法相比較，有著低耗能及環境友善等優點，處理後能產出優異的水質，唯提高通量與減 少薄膜積垢仍是研究薄膜處理的重要關鍵。 本研究以我國半導體晶圓廠化學機械研磨製程廢水為研究對象，以結合掃流式與截流式薄 膜系統處理CMP 廢水。先以多段掃流式薄膜單元提升廢水處理效能後再以截流式薄膜單元 做徹底的固液分離，並回收CMP 奈米顆粒，並評估資源化與資源化之可行性，研究參數中 包含、原水水質、薄膜種類、最適通量、掃流式與截流式結合之處理與回收顆粒時機及出流 水水質探討，期望藉此達成高效率水回收與CMP 污泥資源化與再利用之目的。

Semiconductor industry is one of the important high-tech industries in Taiwan. In recent years, the water consumption of IC plant chemical mechanical polishing (CMP) process increase rapidly due to the modification of technic, process upgrade and extension of new plants. The CMP wastewater has difficulties to treat because it contain nano-size particles and complex chemical agents. Presently, suspension solid is the main item of wastewater quality control, but it’s not suitable for CMP wastewater which contain nano-size particle. Thus, Science Park Administration defined the rule of water recovery so it’s a challenge to development lower cost, energy consumption and high efficiency water treatment and recovery technologies. Membrane technology is a solid/liquid separation method. It is now cheaper and widely use in wastewater treatment, tap water supply and sea water desalinization. Compare with traditional treatment process, it has such advantages like low energy consumption and environmental friendly. Although the permeate is clean, to increase flux and lower membrane fouling are the keys to research membrane process. This study will combine crossflow and dead-end membrane system to treat CMP wastewater from semiconductor plant process. First, use multi crossflow membrane units to improve treatment efficiency. Then totally separate and recover CMP nano particle by dead-end membrane unit. To investigate the factors include feed water characteristics, membrane type, flux, membrane fouling, and discuss the possibility of recover and recycle about permeate water and CMP sludge. Finally we expect to improve efficiency of water recovery and recycle CMP sludge for other applications.