Membrane Life Is a Significant Component of The Operating Costs of MBRs

Membrane life is a significant component of the operating costs of membrane bioreactors (MBRs). Here the membrane life has been determined by analysis of all ZeeWeed MBRs installed in North America since their introduction in 1996. It is found that the estimated membrane life of the current product should be greater than 10 years. Membrane bioreactor (MBR) technology has evolved rapidly over the past two decades, with significant gains in performance and reliability, and reductions in costs. While the MBR process is recognised for providing superior effluent quality in a small footprint, it carries additional operating costs associated with the membrane system – including the periodic replacement of the membranes, which have a life shorter than the civil components of the plant. The methodology used here by Canadian researchers to determine membrane life is to analyse the entire data set of ZeeWeed MBR membranes shipped to North American sites over the period of 15 years since their commercial introduction. This analysis shows that membrane life for the current generation product should be greater than 10 years. The analysis also considers the various mechanisms of ageing and end-of-life triggers. It is determined that a slow increase in operating pressure and the need for more frequent chemical cleaning should be the dominant end-of-life trigger with the current product. The most effective method for membrane replacement is a planned campaign, where a fixed portion of the plant – typically dictated by the membrane train configuration – is replaced on an annual basis in the period of time around the anticipated life of the membranes. Source: workingwithwater.filtsep.com