Abstract: All 3520 days permeate volume and trans-membrane pressure of an A2/O-MBR RWTP in Xi'an Siyuan University have been indiscriminately used to study an evaluation method of MBR hollow fiber membrane replacement. The industrial permeability, VMD, has been defined as a fraction with the numerator of permeate volume and the denominator of trans-membrane pressure, m3/ (1000-m2.day.kPa), without temperature normalization. Based on our practical operation, as membranes age, three phenomena can be observed simultaneously. The VMD is decreased 0.78 m3/ (1000-m2.day.kPa), about 4.28% annually； The TMP is increased 0.66 kPa, about 3.50% annually, and the present production capacity is decreased 47 m3 per day, about 2.47% annually； The frequency of cleaning events is increased. In a practical point of view, the membrane replacement interval is a technical and economic planned exercise. Even though, data used in this paper have come out with limitation, but the methodology used still be meaningful.

Keywords: membrane bioreactor; membrane replacement; industrial permeability； trans-membrane pressure; annual permeability attenuation.

| DOI: 10.17148/IARJSET.2022.9921