Evoqua’s CoMag® System Selected by Severn Trent Water for Phosphorus Removal at Finham Facility

Mar 21, 2018

Evoqua Water Technologies has been selected by Severn Trent Water and its design and construction partner, Costain Ltd., to supply Evoqua’s CoMag® ballasted clarification system to reduce phosphorus at the Finham Sewage Treatment Works in Coventry.

Finham will be Europe’s first wastewater treatment plant with a permanent installation of Evoqua’s ballasted settling technology, which has been proven in facilities throughout the United States for more than a decade.

“After evaluating several technologies, we selected the CoMag system because it allows us to cost effectively meet new phosphorus discharge limits,” said Peter Sugden, programme manager for Severn Trent Water. “We are saving a significant amount of money by reusing existing but redundant sand filter infrastructure as the reaction tanks. We are also saving space by using custom-designed clarifiers from Evoqua that can process wastewater ten times faster than a conventional clarifier, thanks to the CoMag system.”

The CoMag system uses magnetite – fully inert, iron ore particles – to enhance the clarification process. The system settles chemical floc up to 30 times faster than conventional clarification.

For communities that face challenging wastewater characteristics due to industrial discharge or dense populations, the CoMag system is the ideal solution. The tertiary CoMag system will help Severn Trent Water reduce both total suspended solids and phosphorus before the treated water discharges into the River Sowe.

Algal blooms and poor river ecosystems are triggered by high levels of phosphorus in the river. To combat the blooms and restore water bodies to “good” status, the UK Environment Agency’s National Environment Programme (NEP) is imposing low phosphorus limits on many wastewater treatment plants, including Finham. The CoMag system will significantly decrease the amount of phosphorus that the works discharges and will ensure compliance with the new phosphorus limit of 0.22 mg/l of total phosphorus (T-P).

“For Finham, the CoMag system has been designed to achieve phosphorus limits of less than 0.18 mg/l T-P,” said Simon Radford, UK sales manager of Evoqua’s Municipal Wastewater Treatment business. “This capability gives Severn Trent the confidence that the CoMag system can meet the 0.22 mg/l limit in the future, even if there are increased demands on the facility from population growth or greater amounts of industrial discharge.”

Currently, the Finham Sewage Treatment Works processes on average 1,597 litres of wastewater every second, which is the equivalent of 14 bathtubs full of water.

About the CoMag System

The CoMag system can achieve total phosphorous down to 0.05 mg/L and can achieve UV transmittance greater than 75 percent when integrated into any type of coagulation/flocculation process or clarifier. Retrofit costs are also reduced with the CoMag system because it is compatible with most existing infrastructure and clarifiers. Additionally, the CoMag system’s magnetite ballast is 75 percent smaller than sand particles and less abrasive, which helps extend equipment service life. More than 99 percent of magnetite is recovered for reuse in the system. For more information, visit www.evoqua.com/comag.

About Evoqua

Evoqua Water Technologies is a leading provider of mission critical water treatment solutions, offering services, systems and technologies to support its customers' full water lifecycle needs. Headquartered in Pittsburgh, Pennsylvania, Evoqua Water Technologies operates 160 locations in eight countries and, with over 200,000 installations and 87 service branches, holds leading positions in the North American industrial, commercial and municipal water treatment markets.


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