Denitrifying submerged aerated filters (DSAF)
With reliable and cost-effective energy efficient blowers, the Rewatec DSAF range provides a robust and efficient long-term solution for larger projects where nitrogen removal is required.

Highly efficient performance
Highly efficient performance
Pre-engineered or bespoke designs
Pre-engineered or bespoke designs
Compact and discreet
Compact and discreet
Perfect for denitrification
Perfect for denitrification
What is a DSAF?
The DSAF process uses individual cells within the tank which are arranged in series. The wastewater flows through each chamber in sequence. Each cell contains media on which biomass forms, and a fine bubble diffuser system feeds oxygen from the blowers to promote the growth of the biomass.

Example applications
- hotels and inns
- leisure facilities
- camping and caravan sites
- schools
- office buildings
- industrial sites
Adaptable to suit your needs
The Rewatec DSAF sewage treatment plant comes in four variations, dependent upon population size and application parameters.

- single tank
- semi modular tank (two tank system)
- modular (three tank system)
- multi stream systems (bespoke application design)
How does the DSAF work?
The Rewatec DSAF sewage treatment plants form three treatment stages; primary settlement, biological treatment (biozone) and humus settlement. Flow through all of the treatment stages from inlet to outlet occurs through gravity and integral airlift.
A blower sends air to the bottom of the bed to provide oxygen for the biomass to support the oxidation process. The air stream promotes both efficient mixing of the effluent and disturbance of any excess solids from the filter medium. The denitrification process also significantly reduces the nitrogen levels within the final effluent.
Rewatec DSAF maintenance
We have a network of local service partners to maximise the life of your Rewatec DSAF system and to provide you with years of reliable operation.
We stand by our products
For over 50 years, we have proudly developed sustainable and long-lasting products that make a real difference for our customers, our professional partners, and above all, our planet.
Our experience in the industry allows us to give you a complete 25 year warranty for our Rewatec DSAF sewage treatment plants and a 12 month warranty for our kiosks.
CPD training course
Our 45-minute CPD certified course "An introduction to off-mains wastewater management" is ideal for Architects, Consultants, Engineers, Installers and Specifiers looking to learn more about what wastewater treatment is and why it is important, regulatory bodies and the current UK regulations, how systems are designed, and what systems are available.
Options and accessories
Personalise your Rewatec DSAF sewage treatment plant to meet your site requirements, with our wide range of options and accessories.
Available products
We offer a complete range of Rewatec DSAF products to meet your needs. From 30PE to 600+PE, wherever your site, whatever the regulations, we have the right sewage treatment plant to transform any challenge into a tailor-made solution.

The Rewatec DSAF range is highly adaptable. As such, we can also provide an above ground wastewater treatment solution to meet your requirements.

The Rewatec DSAF has been designed to have minimal visual impact on site location. This includes a complete below ground installation.

Free quote
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