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Primary and secondary clarification

The aim of the primary and secondary clarification processes is to remove all floating and settleable solids, as far as possible, and to draw off clear water. Aqseptence Group develops robust, low wear scraper technologies for the removal of sediments in circular and longitudinal tanks, which are suitable for a wide range of installation conditions and requirements.


Primary clarification is normally installed downstream of the grit removal and completes the inlet works / headworks. After biological processing, the water / sludge mixture is
separated in the secondary treatment process.
In order to separate the water from the solids, the wastewater is allowed to settle in sedimentation tanks so that the sludge is deposited on the tank bottom and the treated water can be drawn off via the launder channels. The sludge sediment is removed by means of scraper blades or suction pipes, whilst the floating matter is scraped from the surface of the water into an outlet channel. The scrapers move at a very low velocity, to avoid a renewed disturbance of the sediment from the bottom of the tank.
The cleaning process is supported in the grit traps by additional aeration systems which stir up floating matter and prevent organics from settling. As aeration alone is not sufficient, sand washers are then utilized to wash out the organics and ensure the separation of the organic content. The result: lower investment and operating costs which lead to a perceptible reduction in disposal costs.
Aqseptence Group offers you durable low wear scraper systems for circular and longitudinal tanks with a tried and tested robust and reliable construction.

Fields of application

Browse through the products offered for Primary and Secondary Claryfication and contact us for more information.

Passavant Grit Chamber Scraper

Passavant Scraper Technology for Circular Tanks

Passavant Scraper Technology for Longitudidunal Tanks

Locations and Contact


Aqseptence Group GmbH, Aarbergen

Sales and Manufacturing Location
Passavant-Geiger-Strasse 1
65326 Aarbergen

Tel: +49 6120 280

Fax: +49 6120 28 2182


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