How Do Aerated Wastewater Treatment Systems Work?

Occasionally referred to as a household sewage treatment plant, your aerated wastewater treatment system is designed to begin the process of cleaning wastewater before it is sent to its secondary treatment area. The aerated wastewater treatment system is the most common of all household sewage treatment systems.

When it comes to understanding the upkeep and wastewater system you have for your household, it’s important to consider how the system itself is actually designed to work.

In this blog post, we’ll be outlining exactly how aerated wastewater treatment systems work and how this results in some common problems with the system.

How the aerated wastewater treatment system works

AWTSThere are four compartments (also known as tanks) to an aerated wastewater treatment system that the wastewater will move through. Each compartment processes the wastewater and it is eventually directed through to the pump and land application area out of the system.

The first compartment is known as the Primary Sedimentation Chamber. Here, wastewater passes in from the house inlet and the majority of solids are consumed by anaerobic bacteria.

After this compartment, the wastewater enters the Aeration Chamber. Here, air is mechanically introduced to the wastewater and this causes a secondary consumption of solids and organic impurities. This time, it is by aerobic bacteria.

Flowing over from this is the tertiary compartment, the Settling Chamber or “Clarification Tank”. This is where any remaining solids drop out of liquid suspension and settle at the bottom of the compartment. From here, they collect in the Sludge Return pipe and are returned to the Primary Sedimentation Chamber to restart the process.

Only the enhanced wastewater around the top of the tertiary compartment passes into the final compartment, the Disinfection Chamber, where it is disinfected with chlorine and pumped into the irrigation zone (land application area).

Common problems with aerated wastewater treatment systems

  • Disruptions to or outages of power can mean the pump burns out and wastewater is not moved through the system.
  • If the tank is too low then stormwater may infiltrate the system.
  • If the amount of wastewater loads becomes intermittent or lower than usual, it can mean a reduced level of treatment.
  • When purchasing the treatment system, if your chosen service provider does not provide regular inspections then underlying problems at any stage of the system may threaten its operating quality.

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Central Septics CastlemaineCentral Septics Castlemaine is a Victorian agent for Eco-Septic, completing septic tank and wastewater treatment work in Victoria, Australia.

Get in touch with the Cental Septics Castlemaine team for the highest quality Eco-Septic septic tanks today. We offer high-quality installation services for Eco-Septic products and can answer any questions you might have about using treated sewage for irrigation. Contact our suppliers Eco-Septic today to find out more.