Sequential Batch Reactor (SBR)

The Sequential Batch Reactor is designed to provide full biological treatment to crude sewage produced in a normal domestic environment. These units are normally installed in situations where there is no public sewer and where a septic tank or CAP is not environmentally acceptable. The SBR treats the effluents to a very high standard (normally to 15mg/litre suspended solids and 10mg.litre BOD) which is suitable for discharging directly into a watercourse.
Benefits

• Unrivalled effluent quality

• Reduces main pollutants including ammonia by 96%

• Reduces phosphates by 88%

• Batch system eliminates peak surges

• Controlled by an integrated programmable control unit

• Automatic " Holiday Mode" aeration cycle

• Powered only by a small air compressor

• Safe - no 240 volt electrics within tanks

The SBR has been designed and built by a leading Tank Manufacture in association with the University of Abertay, Dundee, and Waste Water Technology Centre, who acted as external consultants. The university carried out an in-depth test programme during which the SBR was tested and evaluated alongside a leading competitor’s model.
The aim of the development programme was to design a unit which was not only very robust and reliable but which would provide outstanding effluent quality without the need for expensive? Add on? Equipment and would also overcome technical problems - (such as media clogging and peak surges through the bio-zone), which most current designs have failed to adequately address.
The final report from the WWTC confirms that the SBR out-performs its rivals in almost every respect and that it has the capability to meet even the most onerous effluent requirement.

Technical information
The SBR is an advanced biological aeration type treatment plant designed to produce a very high quality of final effluent in addition to overcoming several of the common problems associated with packaged domestic sewage treatment units.

Common problems which can occur are:

• Peak surges flow (i.e. mornings and evenings) can
  force effluent through the plant before it has had
  sufficient treatment time

• Fixed film? Types, which have a "media" matrix,
  can suffer from media blockage because of
  excessive bacteria growth. Replacement/maintenance
  of the media material may be required at regular
  intervals

• Mechanical/electrical components within the tanks are
  difficult to maintain and can be a safety risk

• The liquor is not spread evenly over the available
  bacteria preventing an adequate oxygen supply
  The SBR overcomes these problems by:

• Operating on a storage and batching system - storing the
  effluent at peak times in the primary settlement tank
  and treating it in small batches throughout the rest of
  the day - thereby ensuring that each batch receives the
  full treatment time

• There is no "fixed" media within the SBR to become
  blocked up - it operates on the "activated sludge"
  principal whereby the bacteria float in suspension in the
  reactor vessel and form an "active soup" of "mixed liquor"

• There are no moving parts or electrical components
  within the tank. All functions within the tank are operated
  by air power generated by a small compressor which is
  housed in a remote kiosk, allowing
  maintenance to be carried out safely and easily

• The bacterium receives a high quality air supply and is
  completely mixed and aerated by the high volume
  bubble diffuser.