Horsley WTW’s raw water supply comes from the River Tyne at Ovingham and the Whittle Dene complex of reservoirs. The Veolia Actiflo plant, part of a works upgrade being carried out by Northumbrian Water’s partners Doosan Interserve Joint Venture, consists of three streams of Actiflo Turbo AC8 units.
The Actiflo Turbo uses Veolia’s ballasted floc, high rate clarification technology in which Actisand is dosed as a seed for floc formation. The resulting rapidly settling flocs means a plant footprint which is 5 to 20 times more compact than conventional clarification systems. The process also provides the option of dosing powdered activated carbon to remove organic compounds and THM precursors – a seasonal problem at Horsley.