STP

A sewage treatment plant is a facility used to treat wastewater before it is released back into the environment. The process of treating wastewater is divided into three stages: primary, secondary, and tertiary. 

• In the primary stage, large objects such as rags, sticks, and stones are removed from the wastewater. This is done using screens and other mechanical equipment. The wastewater is then pumped into a sedimentation tank where the solids settle to the bottom of the tank and are removed. 
• In the secondary stage, biological treatment is used to remove organic material from the wastewater. This is done by introducing bacteria and other microorganisms into the wastewater, which consume the organic matter and convert it into gases such as carbon dioxide and methane. 
• In the tertiary stage, the wastewater is disinfected to remove harmful bacteria and viruses. This is usually done using chlorine or ultraviolet light. The treated wastewater is then released back into the environment. The entire process of treating wastewater can take anywhere from a few hours to several days depending on the type of treatment plant and the amount of wastewater it needs to process. The treated wastewater is generally safe for human contact and can be discharged into rivers, streams, and other bodies of water.

In addition to the three stages of treatment described above, some wastewater treatment plants also use additional treatment processes such as nutrient removal, advanced oxidation, and filtration. These processes help to further reduce the amount of pollutants in the wastewater and make it safe for discharge into the environment. The process of treating wastewater is an important part of protecting the environment.