Severn Trent Water selects Suez’s ZeeLung to meet ammonia targets

Severn Trent Water has installed Suez’s ZeeLung Membrane Aerated Biofilm Reactor (MABR) technology at its Spernal sewage treatment works (STW) in Redditch, Worcestershire, UK.

The ZeeLung installation, at Severn Trent Water’s Resource Recovery and Innovation Centre at the Spernal STW, will treat a hydraulic capacity of approximately 5800 m3/d. It was designed to upgrade one lane of the existing Spernal STW activated sludge system to demonstrate the ability of ZeeLung to intensify treatment and reduce energy consumption. The project includes the supply and commissioning of five ZeeLung cassettes and ancillary equipment.

The full-scale installation will be used to demonstrate the benefits of the technology to meet more stringent effluent ammonia targets that are a requirement of the newly enacted Asset Management Plan (AMP7) for the UK’s water sector.

The project is part of an innovation strategy focused on the circular economy and net zero carbon emissions, and will be used to promote the adoption of new technologies aimed at intensifying the biological process of existing wastewater treatment schemes without adding civil works.

ZeeLung technology is used to retrofit conventional activated sludge plants for nutrient removal and capacity expansion. ZeeLung employs a gas permeable media to deliver oxygen to a biofilm attached to the media surface. With ZeeLung technology, oxygen is delivered through molecular diffusion without the use of bubbles, which reduces the energy required for oxygen transfer by up to four-times. This allows plants to significantly reduce their energy footprint while also increasing capacity and improving treatment quality.