Pushing MBR Design Further to Drive Reuse in the Face of Scarcity

Veolia recently shared the latest findings from its work pushing membrane bioreactor (MBR) technology to new performance thresholds. Our presentation detailed a pilot project that tested the limits of solids and hydraulic retention times, high-flux operation, and membrane fouling tolerance — all in service of enabling a lower cost of ownership and more flexible system operations.

The session reflected the growing momentum behind MBR as a core building block for both non-potable and potable reuse. As regulatory frameworks evolve and utilities aim to make better use of limited water supplies, the performance and reliability of MBR systems continue to offer a compelling solution. 

MBRs are often the preferred technology for reuse applications because they combine biological treatment with membrane filtration in a single step, producing consistently high-quality effluent. The ability to meet stringent nutrient and pathogen removal requirements, being ideal effluent for feeding downstream unit operations in advanced reuse flowsheets and their cost effectiveness makes them ideal for water reuse.

Unlike conventional activated sludge (CAS) systems, MBRs eliminate the need for secondary clarifiers and tertiary filtration.  They consistently produce improved effluent quality by physically retaining suspended solids and microorganisms with the membrane barrier. That makes them especially well suited for applications where space is limited, effluent quality must be tightly controlled, or additional barriers are required for pathogen removal credit.

Evolving biological design to lower costs and improve resilience
As water recycling becomes a necessity for communities to have a sustainable water supply the cost of implementing additional treatment for recycling can be a huge burden on utilities.  Therefore, there is a need to innovate in a way that can enable cost saving for all treatment technologies, including MBR systems. We showed how thoughtful changes to biological design can make a measurable impact on capital and operating costs without sacrificing performance.

The focus of this session was on lowering solids retention time (SRT) and hydraulic retention time (HRT) to reduce aeration needs and bioreactor size. A potable reuse pilot at the Encina Water Authority in North San Diego County, California, demonstrated that MBRs could maintain stable performance at just three hours of HRT and aerobic SRTs as low as 4.7 days. These parameters were stress-tested with high membrane flux rates for a variety of time periods to simulate abnormally high peaking events. The system maintained complete nitrification, showed strong filterability and handled colder winter temperatures without performance loss.

A New Precedent for Water Reuse in Latin America
Recently, Veolia was selected to deliver Latin America’s world’s first large-scale facility to convert a municipal wastewater treatment plant into a water reuse production station combining advanced membrane bioreactors and reverse osmosis to address key challenges such as biological phosphorus and nitrogen removal, delivering a cost-effective and reliable supply of high-quality water. 

Located in Brazil, the Vitória Water Reclamation Station will have a processing capacity of 38,880 cubic meters per day, regenerating 85% of the Camburi basin's wastewater. This will provide a secure water supply for major industrial users like ArcelorMittal and Vale, both essential to the region's socio-economic development.
This groundbreaking project, which is the first of its kind to emerge from a public tender for water reuse in Brazil, transforms an underused waste stream into a valuable resource. When in operation, the facility will produce enough recycled water for industry that will in turn free up the equivalent local freshwater to supply nearly 200,000 people, setting a precedent on how to increase water resilience with advanced, decentralized water reuse, currently representing less than 1% of total water consumption, according to the Brazilian Water Agency statistics (ANA). 

High-performance water reuse
Veolia’s work on MBR system design reflects a deep understanding of what it takes to deliver reliable, cost-effective reuse treatment. From pilot testing to full-scale implementation, our team helps utilities rethink biological design, optimize membrane operation and support water recycling goals in the face of growing scarcity.

With decades of experience and proven technologies like PROflex, ZeeWeed and Reverse Osmosis and more recent innovations like memDENSE, Veolia is ready to help your facility meet its reuse objectives. Contact our experts to learn how we can support your next project with best in class advanced treatment solutions.