Actiflo® High Rate Clarifiers
Scottish Waters’ WTW at Newmore in the Scottish Highlands supplies 9 million litres of drinking water per day (Ml/d). The raw water source for Newmore WTW is characterised by high colour, particularly from the peaty soil in the catchment area. This can give rise to very rapid increases in raw water colour and natural organic matter, particularly following rainfall after a prolonged dry period.
Scottish Water needed to increase the treatment capacity of the works while improving the process response to sudden high raw water colour events, often combined with a turbidity increase.
Veolia Water Technologies provided the process design, construction, installation, testing and commissioning of 2 package unit Actiflo® high rate clarifiers. The project included the sand storage and transfer system, polymer make up and dosing system, coagulation and pH correction system, MCC and software for the process.
Furthermore, due to its ability to start-up and achieve treatment requirements within minutes, Actiflo® has proved to be more effective and versatile than the original clarifiers in dealing with the raw water variations.
The Actiflo® process is a patented compact clarification system that utilises microsand as a seed for floc formation. The resulting sand-ballasted floc displays rapid settling characteristics that permit clarifier designs with high rise rates and short retention times. These designs result in system footprints that are between 5 and 20 times smaller than conventional clarification systems of a similar capacity. Actiflo® is ideally suited for difficult-to-treat waters, such as rapidly fluctuating water sources.