Packaged Sewage Treatment Plants

Packaged Sewage Treatment Plants

Packaged Sewage Treatment Plants

Designed and tested in accordance with BSEN12566-3:2005 and with the The British Water Code of Practice for Flows and Loads, the ASP will serve a population range from 6-25 persons and is suitable

for residential and commercial projects where mains drainage is not available. Typical applications include single dwellings, small communities or developments, refurbishments and septic tank conversions.

For homeowners and self-builders the key features of the new Clereflo ASP are its discreet below ground installation, its quiet odourless operation and the low ongoing maintenance and running costs. For builders and developers, as well as being price competitive, the ASP’s compact design offers a low-cost, easy installation process.


Process and Plant Description

The Clereflo ASP treatment plant comprises a single tank. Within the tank there is an inner central bio-zone chamber and an outer  settlement zone. The plant accepts and treats the incoming sewage, using the extended aeration principle, in the central bio-zone chamber.

A simple coarse bubble diffuser, housed in a draft tube, introduces the air that provides the oxygen to the bacteria, which then treats the sewage.

The bio-zone retains the mixture of sewage and bacteria until the level of treatment has been achieved. The treated effluent then enters the settlement zone where settlement

takes place. The settled solids are drawn back towards the draft tube, with the diffuser in it, and are returned via the airlift principle to the

bio-zone for further treatment. The treated (final) effluent subsequently leaves the plant over a weir, at the outlet level, that extends around

the circumference of the tank. The movement of fluid through the whole system will be by gravity displacement or if using our pumped system, this will be displaced via the integrated pump chamber to the point of discharge.


Optional Extras


Extension kit

Deeper inverts can be accommodated by means of an access extension kit which is available in 1.0m length. These are designed to be cut to suit on site and can also be retrofitted, again on site, taking away the worries of installing at incorrect levels.


Package Pump Stations

Inlet sewage and final effluent pump chambers are available in single or dual units, at varying inverts designed to suit the customer’s on site

requirements. Again these can be retrofitted if problems occur during installation.


Sample Chamber

A Sample Chamber is required in order for the regulatory authority to take representative samples of the final effluent for testing.


Package sewage treatment plants are installed to treat wastewater and to protect the environment. They must be cared for and maintained so

that they can continue to operate effectively. Failure to do this will undoubtedly lead to pollution of the water environment, which is an

offence and may result in prosecution.


For the Sewage Treatment Plant it is recommend that a maintenance agreement is taken out to service the plant as indicated in the

Environment Agency Guideline PPG4.

 A plant de-sludge should be carried out between 1 and 3 years (depending on the plant loading).