Non-Electric Monoblock

Designed and manufactured by BioRock, the Monoblock sewage treatment plants are unlike most other sewage systems as they do not require any electricity and use a completely natural process for the ‘treatment’ of wastewater.

Used for rural properties without access to mains drainage, the Monoblock non-electric sewage treatment plant can cater for up to six-persons. Designed to operate effectively for both permanent and seasonal use, the Monoblock system works without any electrical or mechanical components and simply uses natural air draft for the aeration of sewage.

Monoblock non electric cross section


  • Completely Silent Operation.
  • 25 Year Tank Guarantee.
  • Low Carbon Footprint.
  • EN12556-3 Certified.
  • Low Maintenance Requirements.

How it works

Contained within a single tank structure, the Monoblock sewage treatment plant functions with a three-stage treatment process.

Stage 1 – Primary Tank

Initially the raw sewage enters a primary chamber to provide separation and the breakdown of organic solids (Primary Treatment). Within this chamber solids settle to the floor of the chamber whilst oils, fats and tissues float to the effluent surface.

Stage 2 – Filtering Effluent

Liquids (effluent) pass through the primary chamber and into the effluent filter before discharging into the Bioreactor.

Stage 2 – Bioreactor

When entering the Bioreactor, liquids discharge onto a Tipping Tray, which disperses the flow evenly onto a distribution plate and treatment media. The media contained within the Bioreactor treats the wastewater naturally with an aerobic digestion process. Air is drawn into the media using an ‘above ground’ air vent / drafting system. The liquids percolate through the Bioreactor media where the aerobic micro-organisms ‘treat’ the contaminants.

Supply & Installation

Since 1988, BioRock has become an internationally acclaimed and experienced leader in the field of onsite and decentralised non-electric sewage treatment technologies. Providing expertise and experience in installing BioRock sewage treatment plants, Mantair engineers can provide advise and a full installation service for property owners. Contact us on 01255 853890 or complete the form below.