Exempt sewage
treatment system
The Allerton MinAir Biofilter
The Allerton MinAir Biofilter is an exempt sewage treatment system suitable for a 3 bed house, 4 bed house or 14 workers in a commercial environment.
Producing high quality effluent the Allerton MinAir Biofilter discharges direct to your watercourse or soakaway.¹
If you are off mains drainage and require an Exemption Certificate from the Environment Agency for sewage treatment, this is ideal for you.
Why use the Allerton MinAir Biofilter
exempt sewage treatment system?
- BBA certified and manufactured in accordance with our BS EN ISO 9001:2008 quality management system.
- BS EN 12566 Part 3 compliant.
- Produces high quality effluent 20mg/l BOD and 30mg/l SS and 20mg/l NH4.
- 3 year warranty on all working parts.
- Low maintenance costs, servicing every year and desludging once every two years. Installation, sewage servicing and sewage maintenance available.
How our exempt sewage treatment system works
See illustration to the right.² Raw sewage flows by gravity into the primary zone (2) of the Allerton MinAir Biofilter. Here, the solids settle out to the bottom of the tank leaving the liquid to pass through to the first of two moving aerated media bioreactors (4).
Each of the bioreactors is aerated by a compressor (1) which pumps air through a bubble diffuser. This flow of air bubbles also causes the liquid and media to circulate within the bioreactors. The constant flow of the liquid in contact with the moving media allows the biomass on the media to purify the liquid.
The treated effluent flows into the final settlement zone (5) where humus sludge settles out. This sludge is re-circulated periodically to the primary zone. The fully treated effluent flows by gravity from the Allerton MinAir Biofilter to soakaway or watercourse.
Environment Agency Exemption Certificate for Sewage Treatment
The Allerton MinAir Biofilter is CE Marked and Certified to the European Standard BS EN12566-3 for small wastewater treatment systems. Customers can apply to the Environment Agency for an Exemption Certificate for this unit so that it can either discharge to surface water (Ditch or River) or to Ground (Soakaway).
¹ An Exemption Certificate is required from the Environment Agency to register exempt water discharge and groundwater activities. ² Allerton MinAir Biofilter illustration is not drawn to scale.
- Compressor
- Primary Zone
- Inlet
- Biorectors
- Final Settlement Zone
- Outlet
Alternative sewage treatment systems
- Small sewage treatment system
- Medium sewage treatment system
- Septic tank conversion
- Wastewater sewage treatment
