本研究探討醋酸纖維膜利用直接滲透技術(FO)應用於水回收之可行性探討。首先利用醋酸纖維素(CA)自行製備之平板膜，藉由電子顯微鏡(SEM)探討薄膜表面結構、表面粗糙度及量測接觸角探討薄膜表面之親疏水性。應用於直接滲透及壓力延遲滲透(PRO)技術試驗，利用氯化鈉(NaCl)溶液做為驅動液(Draw Solution)，以生活污水為進流液，探討兩系統之滲透量、鹽阻率及水回收效益之影響。
實驗操作變因如下(1)鑄膜液之不同醋酸纖維素濃度、(2)FO及PRO操作技術試驗之影響、(3) Draw Solution之濃度變化、(4) Feed Solution變化對不同濃度醋酸纖維膜之過濾效果。
結果顯示鑄膜液之高分子CA濃度12wt%，因薄膜孔洞較緻密導致通量較低，但鹽阻率較高且有助於以FO技術回收生活污水時，有效阻擋氨氮、COD、TOC、鈣、鎂、銅、及錳等金屬濃度，達到本次實驗之研究目的。 In this study prepared by different concentrations of cellulose acetate(CA) for the forward osmosis (FO) and pressure retarded osmosis(PRO) process applies in the domestic sewage recovery technology. Membrane structure, pore size, and surface porosity characterized by scanning electron microscopy (SEM). Measuring hydrophilicity of membranes by contact angles. Using NaCl solution as the draw solution by conducting the batch FO and PRO process, the water flux and salt rejection for the prepared membrane were measured.
Experiments of filtration by forward osmosis system were conducted under various operating conditions including cellulose acetate concentration, draw solution concentration, and feed solution.
The results show that CA membrane is dense structure. Water flux achieved by the 12wt%CA membrane was much lower than 8wt%. 12wt%CA membrane had high salt rejection, and rejected NH4＋, COD, TOC, Ca2＋, Mg2＋,Mn2＋ and Cu2＋ of feed solution effective. NH4＋rejection higher then 99%.
