sewage treatment plant

How Does a Domestic Sewage Treatment Plant Work

If you are wondering “how does a domestic sewage treatment plant work” we’re here with the answers. Read this guide to learn more about one of the top wastewater treatment solutions available on the market.

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sewage treatment plant

How Does a Domestic Sewage Treatment Plant Work



Domestic sewage treatment plants are a fairly recent invention. They were created as sophisticated alternatives to septic tank systems and are mostly used in parts of the UK where mains drainage is not available. Of course, since domestic sewage treatment plants are a relatively new technology, people are not as familiar with them. From time to time, someone will ask, “How does a domestic sewage treatment plant work?” Read on to learn all about the ins and outs of the functions of domestic sewage treatment plants!

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Early Sewage Treatment Processes 

The process of treating domestic sewage basically consists of a series of filters. Each filter removes a certain kind of contaminant from the water. As a good rule of thumb, earlier treatments will remove larger contaminants, while later treatments will remove smaller contaminants.

The first filter in a domestic sewage treatment plant consists of a simple screen. This first screen will have relatively large holes. 

It is not designed to really make the water any cleaner. Instead, its purpose is to remove any large objects from the water. 

These objects will generally consist of plant material like sticks or bunches of leaves. In some cases, they might also include items like rags that have been disposed of improperly. 

It is important to remove these items so that the treatment plant remains free from the damage they can cause to more delicate processes later on.

The next two parts of early treatment at domestic sewage plants rely on gravity to clean water. They run water through a series of chambers. 

In each chamber, the water flows for some amount of time before moving on to the next chamber. The chambers have short walls that the water flows over. 

The end result is that the heaviest contaminants in the water sink to the bottom of the chambers. This allows the water to flow to the next chamber free of those heavier contaminants. 

The first couple of tanks like these remove contaminants like grit and sedimentation.


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Later Domestic Sewage Plant Processes

Later stages in the treatment process address subtler contaminants. These include organic and chemical contaminants.

The water is run through a series of interlocking corrugated plastic sheets. On the sheets, there are special bacteria that eat up many organic contaminants.

Later on, the water will be mixed with chlorine to disinfect it. At the end of the process, the water will not yet be ready to drink or wash with, but it will be safe to return to the environment.

Learn How a Domestic Sewage Treatment Plant Works

If you have ever wondered how a domestic sewage treatment plant works, we hope that this brief article on the subject has given you an increased understanding. Along with septic tanks, domestic sewage treatment plants are one of the best options for managing the waste products of an ordinary home. Regardless of which of these options you choose, it is important to find a quality provider. 

To learn more about domestic security plans, septic tanks, and more, feel free to reach out to us at any time here! 

How do sewage treatment plants work?

Stage 1: the primary settlement chamber

In the first stage of sewage treatment, anaerobic breakdown takes place in the primary settlement chamber. The wastewater is introduced and the solids drop to the bottom, becoming separated from the liquid.

Stage 2: the aeration chamber

The next stage of the wastewater treatment involves aerobic breakdown. This takes place in the aeration chamber, where masses of naturally occurring bacteria inhabit specially designed filter media.

These bacteria are sustained with air, which is continuously supplied from a purpose-built pump in the unit’s top section. As the liquid flows slowly through the filter media, the bacteria feed on the waste and remove it from the liquid.

Stage 3: final settlement chamber

In the last stage of wastewater treatment, the liquid flows from the aeration chamber into the final settlement chamber. Suspended sludge consisting of bacteria is carried with the liquid into the settlement chamber and settles to the bottom of the chamber.

From there, a continuous sludge return system pumps it back to the primary settlement chamber. The remaining treated liquid now meets the required standard to be safely passed out of the Tricel system.

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    Tricel Environment UK

    A trading brand of Dewey Waters Ltd.,
    Tricel Weston, Winterstoke Road, Weston-super-Mare, BS24 9AN, United Kingdom.
    Tel: +44 (0)1934 422 311