Fundamentally, a sewage treatment plant functions by circulating air to encourage the growth of bacteria to break down sewage. The goal is to deliver much cleaner, more environmentally friendly effluent. It involves a similar process to a typical septic tank but has some key differences. Depending on their size, sewage treatment plants can treat the waste of commercial properties or a number of domestic dwellings.
What Are The Stages of Sewage Treatment?
General construction of a sewage treatment plant is very similar to that of a septic tank. Sewage flows from the property being serviced into the first chamber of the sewage treatment plant, just as it does with a septic tank. In this tank, the water sits until grease, oil, and scum have floated to the top and solids have settled to the bottom.
Once the separation process has taken place, the liquid travels into a second chamber, where sewage treatment plants differ from septic tanks. This chamber is fitted with an air pump that circulates air around the chamber to encourage the growth of aerobic bacteria. This bacteria helps to break down the contaminants in the water, effectively cleaning it.
The final stage of a sewage treatment plant is one last settlement tank. This final tank allows the very last solids that may remain to sink to the bottom of the tank before the effluent is discharged into a soakaway or watercourse.
After the treatment process is completed and the wastewater has been treated thoroughly, it can be discharged into the environment. A sewage treatment plant differs from a sewage treatment plant in this important aspect. Whereas you must discharge effluent from a septic tank into a soakaway for further treatment in the ground, subject to an Environment Agency Consent to Discharge, you can discharge your effluent into local water sources straight from your treatment plant. Due to the vastly improved effluent quality produced by the treatment process, this is the case.
Why Are Sewage Treatment Plants Required?
The first thing anyone planning a new development should do is get connected to the main sewer system. Wastewater treatment plants are usually the most cost-effective and reliable option. However, getting a mains sewer connection isn’t always possible. In some scenarios, the distance from the nearest sewer or the layout of the land can make it impossible to have your property serviced by a mains sewer. That’s where sewage treatment plants and other alternatives come in. As long as you have an electrical connection, you can install a sewage treatment plant almost anywhere.
Do Sewage Treatment Plants Still Need Emptying?
The aim of a sewage treatment plant is to treat wastewater as thoroughly as possible. However, even though such plants can often handle more waste than a septic tank, they still need to be emptied periodically. Over time, sludge can also build up in the system, so it’s important that a treatment plant is regularly maintained at least once a year or as the installer advises you.
Advantages of a Sewage Treatment Plant
- Reliable and unlikely to encounter problems with only regular maintenance
- Can be installed even on challenging or compact sites
- Cost-effective over time, with only installation, power and maintenance to pay for
Disadvantages of a Sewage Treatment Plant
- The plant needs a constant supply of electricity to run
- Will require professional maintenance annually, and in the unlikely event of problems
- Design and installation of the system needs to be undertaken professionally
Having a sewage treatment plant has the biggest disadvantage of relying heavily on professional maintenance. Because of this, you have to wait for any problems to be resolved, no matter how unlikely they are, which makes selecting the supplier of the service absolutely crucial.