کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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6368025 | 1316896 | 2011 | 9 صفحه PDF | دانلود رایگان |
The critical flux and chemical cleaning-in-place (CIP) in a long-term operation of a pilot-scale submerged membrane bioreactor for municipal wastewater treatment were investigated. Steady filtration under high flux (30Â L/(m2Â h)) was successfully achieved due to effective membrane fouling control by sub-critical flux operation and chemical CIP with sodium hypochlorite (NaClO) in both trans-membrane pressure (TMP) controlling mode (cleaning with high concentration NaClO of 2000-3000Â mg/L in terms of effective chorine was performed when TMP rose to 15Â kPa) and time controlling mode (cleanings were performed weekly and monthly respectively with low concentration NaClO (500-1000Â mg/L) and high concentration NaClO (3000Â mg/L)). Microscopic analysis on membrane fibers before and after high concentration NaClO was also conducted. Images of scanning electron microscopy (SEM) and atomic force microscopy (AFM) showed that NaClO CIP could effectively remove gel layer, the dominant fouling under sub-critical flux operation. Porosity measurements indicated that NaClO CIP could partially remove pore blockage fouling. The analyses from fourier transform infrared spectrometry (FTIR) with attenuated total reflectance accessory (ATR) and energy dispersive spectrometer (EDS) demonstrated that protein-like macromolecular organics and inorganics were the important components of the fouling layer. The analysis of effluent quality before and after NaClO CIP showed no obvious effect on effluent quality.
Journal: Water Research - Volume 45, Issue 2, January 2011, Pages 863-871