Europe’s Largest Potable Water Brine Electrochlorination Plant Selects System for its Disinfection Needs

Severn Trent Services (UK), has supplied its ClorTec on-site hypochlorite generating system for the largest potable water brine electrochlorination plant in Europe to address the need to reduce risk from bulk storage of liquid chlorine, as part of a £35 million upgrade. The improvements at Huntington Water Treatment Works in Chester, England, are part of a £3.6 billion investment by United Utilities across North West England.

The original project scope called for the construction of a new facility to store drums of liquid chlorine on site. However, the project team identified an alternative process that would eliminate the need to store hazardous liquid chlorine, reducing the risk to operators, and demonstrate best practices in Health & Safety.

Severn Trent Services installed six ClorTec HCT-1500 units, which each have a production capability of up to 680 kg/day of chlorine equivalent. Overall the units have the potential to produce 4,080 kg/day of chlorine equivalent and so are able to produce the 3,360 kg maximum chlorine demand at Huntington in an operating period of 20 hours.

Generating sodium hypochlorite on-site is a simple and straightforward process. The ClorTec system operates by feeding a mix of softened water and brine at a three percent solution through electrolytic cells. A low-voltage DC current is applied and a 0.8 percent sodium hypochlorite solution is produced.

United Utilities area business manager Alex Bolton said, “The ClorTec system allows us to replace bulk chlorine with a much safer alternative for our employees.”

In 2013 Severn Trent Services was recognised as a pioneer of stable, safe and sustainable electrochlorination technology when it received the Global Water & Wastewater Disinfection Systems Technology Leadership Award from Frost & Sullivan.

In addition to the six units installed at Huntington, Severn Trent Services has also supplied ClorTec units to other United Utilities sites. These include Sutton Hall and Oswestry water treatment works with a combined daily water treatment capacity of 2,312 kg.