zeeDENSE* Membrane Aerated Biofilm Reactor:

Super-Intensification of Activated Sludge

Veolia’s zeeDENSE MABR is a state-of-the-art application combining ZeeLung MABR & densification technology for activated sludge plants that need to expand both biological and hydraulic capacity by up to 50% while simultaneously improving nutrient removal.

Overview
How It Works
Case Studies
Resources

Overview

Activated sludge plants typically have two process bottlenecks that limit treatment capacity:

Bioreactor capacity is limited by the tank volume and inventory of bacteria in the system. This constrains the amount of nutrient removal that the process can achieve.

Secondary clarifier capacity is limited by the clarifier surface area and the settling characteristics of the mixed liquor.

zeeDENSE MABR breaks through both bottlenecks by combining two proven intensification technologies – ZeeLung MABR & densification.

zeeDENSE MABR Benefits:

Increased treatment capacity for biological reactors and secondary clarifiers
Improved settling
Enhanced nutrient removal, including biological phosphorus removal
Greenhouse gas mitigation
And more

Municipal wastewater treatment applications:

Plants with footprint constraints and increasing capacity demands
Plants needing improved nutrient removal

How It Works

zeeDENSE MABR couples the synergies of ZeeLung MABR and densification.

ZeeLung MABR intensifies nutrient removal in existing bioreactor tanks. ZeeLung cassettes are immersed in the mixed liquor and support the growth of a biofilm that increases the inventory of nutrient removal bacteria in the system. The ZeeLung media “breathes” – transferring oxygen to the biofilm without the use of bubbles, which reduces energy and mitigates N2O emissions. ZeeLung can deliver up to 50% capacity expansion while reducing aeration energy by up to 75% and mitigating greenhouse gas emissions.

Densification intensifies secondary clarification. Hydrocyclones technology use gravimetric selection pressure to retain dense biomass & selectively waste less dense biomass, including filamentous bacteria. Waste activated sludge or mixed liquor is processed through the zeeDENSE system and the dense biomass is returned to the bioreactor while the less dense biomass is wasted from the process. The result is improved settling characteristics of the mixed liquor, which enables up to 50% intensification of secondary clarification.

zeeDENSE MABR is tailor made for the upgrade of activated sludge plants with modularity, process flexibility, and speed of implementation The combination of densification and ZeeLung MABR creates a wastewater technology more efficient than ever without having to increase your plant footprint.

Case Studies

ZeeLung MABR & zeeDENSE MABR intensify wastewater treatment at the Yorkville-Bristol Sanitary District: Download Full Case Study

The Yorkville-Bristol Sanitary District faced multiple challenges including capacity constraints from population growth and industrial loads, space limitations, and phosphorus discharge compliance requirements. In 2017, they implemented ZeeLung MABR technology as a solution. When increased flow created new clarifier capacity challenges, the facility was further upgraded in 2023 with zeeDENSE MABR technology to address these ongoing needs.
zeeDENSE MABR technology intensifies nutrient removal at United Utilities Bolton Wastewater Treatment Works: Download Full Case Study

United Utilities facility in Bolton, UK, faced challenges to meet stricter ammonia limits while increasing plant flexibility, supporting sustainability goals, and enhancing climate change resilience. They chose zeeDENSE MABR technology as the solution, making Bolton WWTP the world's largest MABR installation at the time of construction.
zeeDENSE upgrade for nutrient removal intensification in Gold Coast Australia: Download Full Case Study

The Elanora facility faced challenges due to regional population growth, requiring capacity expansion to 144,000 PE over 25 years, while conventional upgrades were cost-prohibitive and limited by space constraints. zeeDENSE MABR technology was chosen as the solution, offering increased hydraulic capacity and enhanced nutrient removal without requiring new concrete tank construction.