| 摘要: | 本研究分為兩個部分，第一部分研究為中部某科學園區污水處理廠之三套不同的薄膜生物反應槽(Membrane bioreactor, MBR)模廠，已現有的操作參數進行半導體廠工業廢水的處理研究，第二部分研究則為增設實驗室規格之MBR系統，並以混凝劑做為前處理，探討降低薄膜阻塞之研究。
第一部分MBR模廠的研究中，現場數據顯示，此操作參數並無法有效的來處理半導體廠工業廢水，第二部分研究中，則以活性污泥與工業廢水配置成不同濃度(分別為4000mg/L、6000mg/L、8000mg/L)，加入不同混凝劑量後(分別為1ppm、3ppm、7ppm)，進行瓶杯試驗(Jar test)、界達電位分析、臨界通量(Critical flux)試驗等實驗，探討混凝劑之效用與薄膜阻塞的變化情形。研究結果顯示，在添加污泥的溶液中，加入聚丙烯醯胺（Cationic Polyacrylamide , C-PAM）後，比單一以半導體廢水加入C-PAM的整體去除效率提升許多。在低污泥濃度時，加入低劑量的C-PAM即可去除污染物質，但於高污泥濃度時，需添加高劑量的C-PAM才能有效的提升處理成效。在8000 mg/L的高污泥濃度下，添加7ppm的高劑量C-PAM的研究中，整體的去除效果較佳，濁度、TCOD、氨氮的去除效率分別為83.7%、25.2%、24.1%。臨界通量的研究中，在3種不同污泥濃度下，未添加C-PAM的最終過膜壓力分別為15.3Kpa、21.95Kpa與29.93Kpa，添加7ppm的C-PAM後，最終過膜壓力分別降低至7.32Kpa、15.63Kpa與15.3Kpa，臨界通量也從原本的12.2 L/m2-hr、9.2 L/m2-hr與9.2 L/m2-hr，分別提升至17.8 L/m2-hr、15.0 L/m2-hr及15.0 L/m2-hr。數據顯示，添加C-PAM後，大大的降低了薄膜阻塞現象，且在高污泥濃度中(8000mg/L)，降低薄膜阻塞可達到50%的處理成效。
This study consists with two parts. The first study, the field operation at the central area of science park with three different membrane bioreactor (MBR) for semiconductor wastewater treated and the second study, in laboratory scale for compared between MBR systems specification and the coagulant mixing with wastewater for pretratement and define the membrane fouling reducing.
In this field data operating parameters is not effective with treating the semiconductor wastewater. As the laboratory study scale, a polymeric coagulant was used as pre-treatment to a membrane bioreactor system treating semiconductor wastewater to evaluate its effect on the MBR performance and in mitigating membrane fouling. Jar tests using three dosages (1ppm, 3ppm, 7ppm respectively) of cationic polyacrylamide coagulant (CPAM) were tested for three (4000 mg/L, 6000 mg/L and 8000 mg/L respectively) different sludge concentrations to determine the optimum dose of coagulant. The results showed that the MBR overall performance is better when adding sludge solution and C-PAM as opposed to only adding C-PAM to a semiconductor wastewater. In the low sludge concentration (4000 mg/L), addition of low doses of C-PAM can remove most contaminants. While in the high sludge concentration (8000 mg/L) high dose of C-PAM ( e.g. 7 ppm) is needed to improve the overall removal efficiency of turbidity, total chemical oxygen demand (TCOD)and ammonia nitrogen (NH4+-N) which are at 83.7 %, 25.2% and 24.1% respectively. In the critical flux study on the three levels of sludge concentration and wastewater mixtures, non-addition of C-PAM resulted to the final trans-membrane pressures of 15.3 Kpa, 21.95 Kpa and 29.93 Kpa for 4000 mg/L, 6000 mg/L and 8000 mg/L respectively. While addition of 7 ppm C-PAM for the same sludge concentrations resulted to reduced trans-membrane pressures of 7.32 Kpa, 15.63 Kpa and 15.3 Kpa and the corresponding critical fluxes were increased from the original 12.2 L/m2-hr, 9.2 L/m2-hr and 9.2 L/m2-hr, to 17.8 L/m2-hr, 15.0 L/m2-hr and 15.0 L/m2-hr for 4000 mg/L, 6000 mg/L and 8000 mg/L respectively. The results showed that addition of C-PAM can reduce membrane fouling and at high sludge concentration (8000mg/L), as high as 50% membrane fouling reduction can be obtained. |
