Upgrading wastewater treatment plants for capacity expansion or nutrient removal is challenged by process complexity, the need for larger tank volumes and increased energy consumption. ZeeLung is an innovative solution that maximizes the treatment capacity from existing tank volumes while also reducing energy consumption.
While conventional solutions require the construction of new tanks and other process intensification technologies can be complex and energy-inefficient, ZeeLung is a simple solution that increases treatment capacity with existing assets and reduces energy.
ZeeLung technology employs a gas-permeable media to deliver oxygen to a biofilm that is attached to the surface of the media. Oxygen is delivered to the biofilm by diffusion without the use of bubbles, resulting in lower energy consumption.
Pollutants — such as ammonia and organics — diffuse from the bulk solution into the biofilm where bacteria in the biofilm have optimal conditions to remove them.
Process intensification with ZeeLung
Installing ZeeLung cassettes into an activated sludge reactor increases the inventory of biomass in the system without increasing the mixed liquor concentration. As a result, the same reactor volume has more treatment capability.
The process interaction of oxygen and pollutants is different in a ZeeLung system compared to conventional active sludge and biofilm processes. With ZeeLung, oxygen and substrates such as ammonia and organics enter the biofilm from opposite sides in a counter-diffusion configuration. This creates conditions that favor the growth of nitrifiers in the biofilm due to the high diffusivity of ammonia into a biofilm, as compared to organic substrates, and the availability of dissolved oxygen, which is highest at the media surface.
Preferential growth of nitrifiers versus heterotrophs means that the ZeeLung biofilm “supercharges” nitrification in an activated sludge system. Simultaneous nitrification and denitrification can be achieved by installing ZeeLung cassettes in an anoxic zone.
Key benefits
Some of the principal benefits to operators using ZeeLung are process intensification with up to 50 percent more treatment capacity and/or performance in existing tank volumes; attached-growth biofilm that is resilient to load variations and upset conditions; simple installation into existing bioreactor tanks; and significant energy savings on oxygen transfer compared to fine bubble aeration.
SUEZ has operations in 130 countries and employs more than 10,000 people worldwide. The company has a comprehensive set of chemical, equipment and digital-enabled services and products, helping customers optimize water resources and overcome process challenges. SUEZ works with customers across numerous industries, including food and beverage; metals and mining; power; chemicals and pharmaceutical; oil and gas downstream and petrochemicals; upstream oil and gas; pulp and paper; and utilities.
