12 Person Marsh Ensign Sewage Treatment Plant

Specifications

Inhabitants: Up to 12 people
Length: 2860mm
Width: 1912mm (+/- 50mm)
Height: 2139mm (+/- 50mm)
Depth to inlet invert level: 550mm (+/- 50mm)
Fall between inlet & outlet: 75mm
Pipe & Fittings: 110mm

Effluent Quality

BOD₅: 11.5 mg/l
NH₄: 8.4 mg/l
SS: 19.2 mg/l

This Ensign:Standard sewage treatment plant is designed to treat household wastewater for properties with up to 12 inhabitants, the Marsh Ensign:Standard is widely regarded as one of the most efficient, reliable and economical sewage treatment plants on the market.

Class leading performance

Tested and approved to BSEN12566-3/A1:2009 all Ensign units provide treatment well within national consent requirements. Published test results of 11.5:19.2:8.4mg/ltr (BOD:suspended solids:ammonia), with influent concentrations on test higher than those chosen by most competitor plants, effectively equates to 97% pollutant removal.

Unrivalled choice

Ranging in size from 4 to 50 PE in Ultra, Standard and Shallow versions of each, and with a wide range of ancillaries, almost all site, consent and budget requirements can be met.

• Optional risers to increase invert depth are available on request.
• Optional pumped outlets are also available on request.

Why choose the Marsh Ensign:Standard?

End users, merchants and installers alike recommend the Ensign range due to its ease of installation, reliability, and cost-effective operation and maintenance. All backed by technical support from local contacts.

• Inlets and outlets with ‘Forsheda seal’ 
  Forsheda seals provide flexibility in the joint for easier installation.
• Low-energy compressor with alarm
  Near silent compressor ensures minimal running, maintenance and servicing costs. Integral alarm detects low pressure in air line.
• Compressor housing - Internal or external options available
  The compressor can be housed internally or externally with no difference in cost. External compressor is recommended to increase compressor life – this is supplied as standard on 4PE, shallow and pumped outlet models.
• PVC pressure pipe/diffuser(s)
  Provides a protective conduit for the air diffuser line. Can be easily removed for maintenance and cleaning.
• Bio-media
  High specification bio-media (310m³ per m²) and membrane diffusers ensure even circulation to eliminate 'dead spots'.
• Nylon mesh
  Retains media in aeration chamber during transportation and handling, and in the event of flooding.
• 32mm sludge return
  Larger diameter sludge return prevents the possibility of blockages and improves system circulation. Provides higher effluent quality whilst balancing flow over a 24-hour period or periods of intermittent use.
• Impermeable lid
  Regular lid/frame improves strength and durability whilst blending into the surrounding environment.
• Integral lifting eyes
  For safe and secure on-site handling.
• Stabilising feet
  Stabilising feet prevents the tank from rolling and allows safe and steady transportation and installation.
• Unique ‘keying-in’ lip
  Assists anchoring into granular or concrete surrounds.

Operating Principle

The tank utilises a three-chamber design to produce its high-quality effluent. The first chamber is where primary settlement takes place and where anaerobic digestion produces clarified water. This water then filters into a second aeration chamber where, supported by diffused air and bio-media, bacteria treats the effluent to remove the dissolved constituents. The third chamber is where final settlement takes place before the effluent is discharged into a drainage field or local watercourse.

General guidance

Package Sewage Treatment Plant's (or PSTP's) are often a suitable option where groundwater in the surrounding environment is vulnerable, drainage field percolation values are restrictive, or direct discharge to a water course or surface water sewer is the preferred discharge method.

• PSTP's should be sized using the latest version of British Water Flows & Loads which provides detailed information on sewage production figures and sizing calculations.
• Regulatory authorities for the control of pollution in the UK normally require treatment plants conforming to BSEN12566:3 to be demonstrated as capable of producing a minimum effluent discharge quality of 20:30:20 (Biochemical Oxygen Demand: Suspended Solids: Ammoniacal Nitrogen in mg/ltr), although in certain areas more stringent site-specific qualities may be required.
• No surface water should enter the system as this can reduce the system's capacity and cause solids to be flushed out which may prematurely block drainage field or cause pollution.
• As with septic tanks sludge should be removed annually or in line with manufacturer’s instructions.

Please Note: Tank configuration and components shown for illustration purposes. Due to production processes, dimensions of finished units are within a tolerance of +/-2.5%.