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Paris — Veolia Water is pleased to announce that its subsidiary, Veolia Water Solutions & Technologies (VWS) has developed the new generation of clarifier for potable and process water. Referred to as the ultimate of all clarifiers, Actiflo® Turbo incorporates the best in water clarification performance and is compact, quick and flexible, making it suitable for the needs of industrial companies in terms of process water, and for municipalities.

Since its introduction by Veolia Water Solutions & Technologies (VWS) in 1989, Actiflo® benefits from constant improvements in order to optimise its performance and applications. With more than 410 installations in the world, VWS benefits from unequalled experience which has enabled the Company to develop and exclusively patent a new generation: Actiflo® Turbo.

The process covers numerous applications and can be integrated into many treatment chains to produce high quality treated water. It is also an innovative solution for the production and recycling of industrial process water through technological combinations.

The system is equipped with a coagulation tank, a flocculation tank which contains a Turbomix™ to enhance flocculation by installing a draft tube around the mixer impeller. This enables optimisation of agitation and thus the flocculation process. After these two tanks there is a lamellar settling tank with a sludge scraper, lamellas and collection launders. A centrifugal pump draws the sludge and microsand towards a hydrocyclone which separates and recovers the microsand.

The Treatment (Step-by Step)
After straining, which separates large-size debris, the treatment can begin. In the first tank a coagulant such as an iron or aluminium salt is injected to the raw water to destabilize the particles in suspension which will form microflocs. The coagulated water is then channelled to the flocculation tank where microsand and polymer are added. The microflocs formed during the coagulation stage are ballasted by the agglomeration of microsand. In the flocculation tank the water is vigorously mixed by the Turbomix™ which causes the microflocs to swell and mature. The microsand has a large contact surface and thus improves flocculation.

Finally, the water reaches the settling tank. While the flocs slide down into the settling tank, the clarified water rises up along the lamellas and is collected by overflow into launders. The mixture of sludge and microsand are collected by a scraper before being pumped to hydrocyclones for separation. The hydrocyclone separates the sludge from the microsand by centrifugal effect. The recycling microsand is re-injected back to the flocculation tank and the sludge is discharged by gravity for further treatment.

Thanks to improvements of the flocculation by the Turbomix™, ACTIFLO® TURBO has become more compact while providing the same treatment performance with reduced energy consumption and lower construction costs. The contact time in the maturation tank has been reduced from 6 minutes to 3 minutes, the injection tank has been eliminated (previous time required by the tank was 2 minutes), the rise rate in the settling tank has risen from 40- 60m/hr to 80m/hr thus resulting in a smaller footprint of the clarifier, and water loss has been reduced by 10-20 times to less than 0.5% of the influent flow, thereby increasing the thickness of the sludge allowing it to be fed directly to the centrifuge or press. Simple and rapid operation makes ACTIFLO® TURBO the ultimate clarifier.

SOURCE: Veolia Water Solutions & Technologies