Process of wastewater treatment in sewage treatment plants.
The wastewater is initially passed through a coarse pretreatment. Here, coarse solids such as stones, sticks, and debris are filtered out. A bar screen removes larger objects, while a grit chamber collects sand and gravel.
The treated wastewater is now directed to a biological treatment stage where it comes into contact with microorganisms. These microorganisms, including bacteria, break down organic substances in the wastewater and produce sludge, which is collected and disposed of in the treatment plant.
In the next step, the treated water is directed into a sedimentation basin. Here, solids and sediments settle down. The sludge generated during the biological treatment also settles down in this stage.