Severn Trent Commissions the UK’s Largest MABR Plant During Lockdown


Press Release | September 14, 2020

OxyMem membrane aerated biofilm reactor (MABR) at Severn Trent’s Spernal site – the largest MABR in the UK 

Ireland, September 14th, 2020 – July marked a milestone for wastewater treatment in the UK, with the installation of 10 OxyMem membrane aerated biofilm reactor (MABR) modules from DuPont Water Solutions at Severn Trent’s Redditch Spernal site in Worcestershire. This central treatment plant has thus become the largest MABR in the UK, all during a period of restricted access to the site due to the COVID-19 pandemic.

The plant processes wastewater from the surrounding catchment area as well as excess biosolids from satellite plants. Consideration for future population growth and tighter ammonia consents led Severn Trent to look for improved process efficiencies.

Rather than expanding the plant, Severn Trent opted for an upgrade by converting it to an IFAS (integrated fixed film activated sludge) MABR system.  DuPont OxyMem MABR modules were simply lowered into the existing anoxic zone on site, over a two-day period, to boost nitrification capacity of the current process. The advanced technology offers simultaneous COD and ammonia removal, with nitrification rates 2-3 times greater than MBBR technology at the design temperatures.

This full-scale installation follows an extensive 12-month pilot trial at Severn Trent’s Minworth site on the northeastern outskirts of Birmingham. There, the OxyMem system proved its value, producing sludge at just 0.13 kg TSS/kg COD applied compared to the typical 0.3 – 0.4 kg of TSS/kg COD applied for activated sludge. Energy consumption was low and the aeration efficiency was 4.5 kg O2/kWh, two to three times more efficient than conventional technologies. 

Following the pilot and successful installation, Justin Silver, innovation project manager said, “Severn Trent is excited at the potential for MABR technology as a cost-effective way to retrofit and upgrade activated sludge plants to meet tightening effluent standards and to cater for population growth.”

A major advantage of upgrading with DuPont OxyMem MABR modules is due to their “plug and play” nature, as the units can be easily lifted and lowered into place without the need to interrupt the process.  Additionally, Severn Trent can install the modules which is particularly important during the current health crisis that has led to certain restrictions for external personnel to enter the site.

“The modularity of this self-contained solution means not only can it be easily dropped into place, but it is also scalable should needs change.”, said John McConomy, commercial director, DuPont’s OxyMem product line. “Severn Trent have put their trust into our system after it proved itself in trials. They are leading the way in the market in terms of low-impact, sustainable wastewater treatment that enhances and protects the investment in existing infrastructure.”

About DuPont Safety & Construction

DuPont Safety & Construction is a global leader in delivering innovation for life’s essential needs in water, shelter and safety; enabling its customers to win through unique capabilities, global scale and iconic brands including DuPont ™ Corian®, Kevlar®, Nomex®, Tyvek® GreatStuff™, Sytrofoam™, and FilmTec™. More on DuPont Water Solutions can be found at

About DuPont

DuPont (NYSE: DD) is a global innovation leader with technology-based materials, ingredients and solutions that help transform industries and everyday life. Our employees apply diverse science and expertise to help customers advance their best ideas and deliver essential innovations in key markets including electronics, transportation, construction, water, health and wellness, food and worker safety. More information can be found at

About Severn Trent

Severn Trent is the UK’s second biggest water company.  It serves 4.4m homes and business customers in England and Wales. Its region stretches from mid-Wales to Rutland and from north and mid-Wales south to the Bristol Channel and east to the Humber. The company delivers almost two billion litres of water every day through 49,000km of pipes. A further 94,000km of sewer pipes take waste water away to more than 1,000 sewage treatment works.

To find out more about Severn Trent’s performance in comparison to other water companies go to