How Many Types of Aeration System in STP Plant? The functioning of Sewage treatment plants is very important in the sense that they are used to remove pollutants from wastewater and discharge it back. But the most significant step in the treatment process is aeration, which involves spraying or injecting air in the wastewater. The oxygen provided assists bacteria in digesting the waste materials making the water cleaner. Visit the link for more information: https://www.netsolwater.com/sewage-treatment-plant-aeration-system-types.php?blog=7117