United Utilities is using pioneering chlorine dioxide (CIO2) to upgrade its Oswestry water treatment works in Shropshire - the first chlorine dioxide system of this scale at a UK water treatment works.
C2V+, a VolkerStevin and CH2M joint venture, is partnering with Scotmas Group to provide the new pioneering system on behalf of United Utilities.
Using chlorine dioxide for the pre-oxidation of iron and manganese contaminants in the water means engineers can retire the existing 23 slow sand filter beds. The new works also include clarification and a new clear water storage tank plus a general site upgrade/modernisation including Rapid Gravity Filters and on site power generation. Once complete this will result in the plant treating up to 210 million litres of water a day for customers.
Graham Callanan, United Utilities project manager, said:
“This is a flagship project for us. Oswestry Water Treatment works is one of our most important sites in the North West, supplying almost a million customers in Liverpool and Cheshire.”
“This £54m investment will help preserve drinking water for future generations and we’re using the latest technology to make this happen.”
The installation will be the first chlorine dioxide system of this scale at a UK water treatment works. The process is used in Europe and in the USA for the treatment of public water supplies. In Italy ClO2 has completely replaced chlorine based treatments in some cities - improving water quality and eliminating Trihalomethane (THM) contamination – making water safer to drink and to bathe in.
Darren Hynes, framework director for C2V+, said:
“We’re excited to be using a system of this size for the first time in the UK. Working with Scotmas will mean we are using the latest technology at Oswestry.”
Alistair Cameron, Scotmas managing director, explained that chlorine dioxide is already widely used around the world for producing safe, clean water supplies; and its advantages over traditional chlorination are well established, commenting:
“With a number of water treatment plants across Europe, the Middle East and Asia now relying on our ClO2 systems for safe and reliable water, we are delighted to have this opportunity to work with C2V+ on bringing this technology closer to home. We expect this to be the first of many with UU and other UK water utilities.”
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