Limitations for transferring lab-scale microfiltration results to large-scale membrane bioreactor (MBR) processes

► Rheology of model feed similar to activated sludge with MLSS ⩽ 3.5 g/L. ► Impact of aeration frequency for single-fibre and single-bundle tests similar. ► Macroscopic circulation flow affects large-scale filtration performance. ► Fibre motion enhances the filtration performance. ► Fibre motion insensitive to packing density variations (⩽4 fibres).