Sewage treatment plant for 21-55 people

The WPL Diamond range from Arti Construction in France offers sewage treatment plants for properties that are not connected to mains drainage. The DMC range includes sizes suitable for 21-55 people.

Maintenance Manual, Installation Manual, Sewage Treatment Product Brochure

Diamond sewage treatment DMC complete

Why Diamond?

There are several key reasons to choose a Diamond solution for your development:

  • Minimal maintenance, low running cost - unlike other sewage treatment plants on the market, the Diamond’s unique design has no internal moving parts.  This means that it requires minimal annual maintenance, making it economical to run.
  • Kind to the environment – the Diamond’s treatment process requires no chemicals, so it’s kind to the environment.
  • Minimal visual impact – the Diamond’s tank is buried entirely underground, so it has minimal visual impact.
  • No smells – most other treatment plants have primary tanks which store settled solids and can emit odours.  The Diamond has no primary tank and is therefore odour-free.
  • Long emptying cycle – the Diamond’s continuous bacterial digestion treats wastewater to a standard that meets all the normal Environment Agency consents.  The DMC range can achieve a de-sludge (emptying) period of up 12 months – much longer than that of most other plants.

Sewage Treatment Process Performance Guaranteed

The Diamond treats wastewater to a 95 percentile standard of:

  • 20mg/l Biological Oxygen Demand (BOD)
  • 30mg/l Suspended Solids (SS)
  • 20mg/l Ammoniacal Nitrogen (AMM-N)

If more stringent environmental requirements are specified, please contact us.

How does the Diamond DMC treatment plant work?

  • Wastewater enters the Diamond via the inlet pipe directly into the central aeration chamber (1)
  • The central aeration chamber (1) empties into the bottom of the outer clarifier chamber (2).
  • A drop pipe (7) releases air through a disc plate diffuser (4).
  • An upward flow of process fluid draws settled solids (5) through the draft tube (3) to discharge at the surface of the aeration chamber.
  • The design of the draft tube (3) ensures complete mixing of oxygen with the sewage. Oxygenation allows aerobic organisms, that biologically degrade wastewater contaminants, to grow.
  • Gravity causes aerated solids to settle at the tank bottom (5) where they are drawn back up through the draft tube (3).
  • Raw sewage displaces biological solids (8)from the aeration chamber (1) to the clarifier chamber (2). Quiescent conditions in the clarifier allow digested solids to settle at the base (5) and  return to the aeration chamber (1).
  • The clarified effluent flows up through the scum baffle (9) and over the weir arrangement (6) prior to discharge via the outlet pipe.
Diamond DMC Schematic

How is the Diamond DMC sewage treatment plant installed?

The Diamond sits below ground and is straightforward to install - often without the need for concrete backfill, subject to ground conditions. A comprehensive installation manual is supplied with each plant, which you should read thoroughly prior to installation. We recommend that you use an experienced and qualified installer – for details of those in your area, please contact a member of the WPL sales team in the UK or Arti Construction in France.

Diamond DMC Installation

The plant is supplied with an air blower, together with an alarm and an enclosure to protect it from the weather.  This comes with 10 metres of airline to connect the blower to the tank.  The Diamond can accommodate longer airlines – up to 30 metres.  Please contact us for more information.

Diamond DMC after installation

After Installation with just the lid visible

Where to use the Diamond DMC range

  • Single houses
  • Small groups of houses
  • Small commercial premises
  • Replacing existing septic tanks

 Download DMS Sewage Treatment Plant Documentation.

Maintenance Manual, Installation Manual, Sewage Treatment Product Brochure

Contact us with any Questions and Enquiries on the Sewage Treatment Plants