Important Terminology in Wastewater Treatment

The average person may not know a lot about wastewater treatment, but considering how many business interests require some form of treatment for the wastewater they produce, it’s handy to have at least a basic understanding of how these systems function.

This begins with learning common terminology associated with wastewater treatment so that you can have an intelligent conversation on the subject. Here are just a few important terms you should know if your business produces wastewater.


Aeration occurs when air is added to water and/or passed through it. This process takes place in aeration tanks and it is the secondary treatment (after solids are separated from the wastewater). Aeration encourages the growth of bacteria that helps to break down any remaining waste solids in the water before water moves on to finer filtration and chemical processing.


Two common types of wastewater treatment processes are dissolved air flotation (DAF water treatment) and dissolved gas flotation (DGF water treatment). The former works by dissolving air in water under pressure and then releasing it into waste water treatment tanks so that tiny air bubbles cling to suspended waste solids and carry them to the surface of the tank for skimming.

The latter method uses nitrogen gas in place of air bubbles to achieve the same goal. While DAF water treatment is often used for industrial interests, DGF is more often used in the oil industry.


When it comes to wastewater treatment, disinfection is the final stage of treatment, used to remove any remaining bacteria, viruses, or other pathogens before clean water is discharged back into waterways or used for irrigation, just for example.


Effluent is just another word for wastewater or waste liquids, sometimes also referred to as sewage. It could be used to describe wastewater at any stage of the treatment process, which is to say untreated, partially treated, or completely treated.

Effluent may flow from any number of sources, but the more important point is that it is being discharged into another body of water such as a river, sea, or ocean.


There are many different types and stages of filtration in the waste water treatment process, but all include passing water through some sort of porous material in order to remove particulates such as waste solids, debris, and living organisms like bacteria, viruses, algae, and so on.


Sludge is a general term used to describe waste solids that settle in treatment tanks. Sludge is scraped away so that cleaner water can go on to the next stage of treatment.

Leave a Reply