Your web browser is out of date.

Update your browser for better security, speed and to get the best experience on this website.

Update your browser
Schematic of complete immersed MBR process, showing screen, blowers and pumpsCredit: Judd Water and Wastewater Consultants
Features arenales fig 7
SEM cross-section of the Rising Sun membrane

MBR basics

Membrane bioreactors provide enhanced biological treatment and clarification through integrating a membrane with the aerobic conventional activated sludge process or CAS, though anaerobic MBRs have also been developed.

MBR technologies were first commercialised in the early 1990s, subsequently achieving rapid implementation in response to the increasing stringency of global environmental legislation for discharged wastewater quality.

Introduction to MBRs

MBRs represent an enhancement of the conventional activated sludge process (CAS), where the usual secondary clarification step is replaced by membrane separation. This offers a number of advantages, including operation at longer solids retention times without impairment of the treated water quality.

Introduction to MBRs
A composite image of different membrane module configurations from different providers.
Credit: Berghof | Ecologix | PCI Membranes | Toray

MBR materials and configurations

Various polymeric and ceramic materials have been used to form membranes for MBRs. The membranes can be configured as three different geometries: flat sheet (FS), hollow fibre (HF), and multitube/multichannel (MT/MC). The membranes can either be immersed in a tank or mounted outside of the tank on a skid.

MBR materials and configurations

From our sponsors…

RisingSun Membrane
Ecologix side banner
Transcend carousel banner
SINAP
Sperta MBR Membrane
immersed membranes in iMBR, schematic

Designing an MBR

The design of a membrane bioreactor system largely relates to the configuration of (a) the membrane (FS, HF or MT/MC), (b) the membrane separation process (immersed or sidestream), and (c) the biological treatment process.

In all MBR processes, the biological stage is a suspended growth process, whereas in a membrane-aerated film process it is configured as a fixed film.


Designing an MBR
Dollar sign
Credit: Judd Water and Wastewater Consultants

MBR costs

MBRs tend to have higher operating costs than the CAS due to the additional energy demanded by the membrane permeation stage. However, capital costs can be lower due to the reduced plant size, and MBRs offer the potential economic benefit of a higher treated water quality.

MBR costs

From our sponsors…

Advert
Advert
Advert