The arguments surrounding the precise target sludge (or mixed liquor suspended solids, MLSS) concentration to use when running an MBR are pretty well developed but what is it that ultimately sets the solids concentration range?
Sequential anaerobic and microalgal membrane bioreactor for water, energy and nutrient recovery from wastewater
The study outlined in this article aims to evaluate a treatment scheme comprising an AnMBR with a downstream algal membrane photobioreactor (MPBR). The AnMBR performance was assessed in terms of its organic carbon removal and biogas generation.
It is most often assumed that the main cost associated with operating a membrane separation plant relates to the energy consumption, followed by the membrane replacement. Consequently, considerable efforts have been devoted to fouling control and mitigation, with more than one fifth of all MBR research literature publications devoted to this topic (Judd, 2017).
The University of Technology in the wonderful city of Sydney, Australia was the venue for the 10th IMSTEC (International Membrane Science & Technology Conference) from 2–6 February 2020. Despite the very real challenges of bushfires and the coronavirus, the organisers – Pierre Le-Clech (University of New South Wales) and Hokyong Shon and Duc Long Nghiem (both of the University of Technology, Sydney), together with their teams of supporting committees and volunteers – delivered a stimulating and well-organised event on behalf of the Membrane Society of Australasia.
The increasing interest in anaerobic MBRs (AnMBRs) relates largely to resource recovery and the circular economy. Anaerobic treatment permits energy recovery through conversion of the organic carbon (OC) to a methane biogas, rather than the considerably more energy-intensive aerobic process which converts the OC to carbon dioxide.
Clogging can take place within MBR module channels as a thick deposit which fills the channel (‘sludging’ or ‘localised dewatering’). Sometimes long rags or braids can develop in the tank itself which wrap around the membrane tank infrastructure (‘ragging’ or ‘braiding’). Chemical cleans are largely ineffective since they can only attack the foulants on the membrane surface, so leaving the clogged material filling the membrane channels largely unaltered. Cranfield University and Qatar University have completed work on this largely neglected research area.