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Aerobic Treatment Units

A 4 Step Process

Step 1

All wastewater from the home flows by gravity into the primary pre-treatment chamber of the ATU, and then into the secondary pre-treatment chamber by way of a mid-water take off. Solids are allowed to settle to the bottom of these chambers and a crust forms on the top. This naturally occurring crust stops odour from escaping from these chambers. Anaerobic (no oxygen) bacteria establish themselves in these chambers and partially digest the organic matter. Any untreatable and potentially harmful solids are retained within these chambers. The mid-water liquor between the bottom sludge based layer and the surface crust then flows by displacement into the aeration chamber.

Step 2

Air is introduced into the aeration chamber by way of a silent Blower with a air diffuser located at the bottom of the chamber. Aerobic (oxygen loving) bacteria proliferate and digest most of the remaining organic material. Fixed biomedia assist the retention and growth of the biomass.

Step 3

The liquid then flows into the clarification chamber for final settling. Sludge is removed from this chamber via an air sludge lift and is returned to the primary pre-treatment chamber for further treatment.

Step 4

The automatic irrigation pump returns the treated effluent to the irrigation field for reuse in the environment.


TMC supplied waste water treatment systems exceed Australian performance standards and produce a colourless and odourless effluent, suitable for either above or below ground irrigation. Quarterly servicing by licensed personnel ensures ongoing system performance bringing piece of mind to you and your family. 

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