本研究利用海綿擔體結合薄膜生物反應槽處理化糞池出流水，實驗室規模的複合型MBR系統包括兩個生物反應器（i）無氧槽及（ii）好氧MBR槽。本研究主要目的為研究不同的操作條件下，瞭解海綿擔體與水力停留時間（HRT）對系統效率與薄膜阻塞的影響，並使用修正型積垢指數（MFI），瞭解操作條件下薄膜阻塞的趨勢。
實驗分三階段進行，污泥由好氧MBR槽返送至無氧槽為1Q，第一階段無海綿擔體添加，總水力停留時間為6小時，第二階段在無氧槽添加海綿擔體，總水力停留時間不變，第三階段則將水力停留時間由6小時縮短為3小時，其餘條件與第二階段相同。
本系統在第二階段有最高的去除效率，TCOD， SCOD氨氮（〖NH〗_4^+-N）和總氮（TN）最高去除率為98.81％，97.53，99.98％ 和82.39％。MFI實驗數據亦說明了海綿擔體的添加可有效降低薄膜阻塞，實驗結果顯示本系統薄膜可在無化學清洗下連續操作116天。研究結果證明此實驗室規模的複合型MBR系統可為化糞池出流水再處理的替代方案之一。 The membrane technologies are getting growing interests for wastewater treatment due to the high removal efficiency and small footprint and also it can be regarded as an alternative way to achieve the design of compact wastewater treatment plants. Even the high quality, however, fouling is always a main problems in membrane bioreactor which is becoming a critical maintenance issue and the membrane performance reduction. The objectives of this study were to examine the test condition, to compare the effects of operating conditions such as sponge addition, hydraulic retention time (HRT) and to investigate the removal efficiency, sludge properties, membrane fouling by using modified fouling index (MFI).
A laboratory scale hybrid MBR process consisted of two bioreactors which included (i) an anoxic tank and (ii) an aerobic tank was conducted in this study. The influences of operating mode as well as the system performance for polishing of septic tank effluent treatment were evaluated. The purpose of this study was to investigate the (i) flexibility of the hybrid MBR for polishing of septic tank effluent as well as (ii) the fouling prevention by sponge addition as a bio-carrier in the anoxic tank. This study also investigated the system performance when operation condition was changed.
The results present several important issues of build-up stage and the removal efficiency of pollutants in terms of chemical oxygen demand (COD), ammonium-nitrogen (〖NH〗_4^+-N) and total nitrogen (TN). The study consisted of three stages, constant permeate flux and recirculation rate was 1Q. The first stage was operated with anoxic combined with oxic-MBR tank. For the second stage, the system was operated with anoxic (which that sponge was supplied as a mobile carrier) combined with oxic-MBR. For the third stage, the condition of HRT was change from 6 to 3 hrs to investigate the performance of this condition.
The highest removal efficiency was obtained at the second stage. The results showed that the highest removal efficiency of TCOD, SCOD, 〖NH〗_4^+-N and TN was 98.81%, 97.53, 99.98% and 82.39% respectively. It indicated that the hybrid system could be an alternative for polishing of septic tank effluent. As for fouling investigation, the results apparently showed that the sponge addition in the anoxic tank was functional for membrane fouling reduction in MBR tank. The modified fouling index (MFI) was employed for the study of membrane fouling rate. The experimental results indicated that the system could be operated without chemical cleaning for 116 days. The study finally led to a conclusion that the anoxic-sponge-MBR process is efficient for treating the septic tank effluent with a low membrane fouling potential.
