[[1]] is removed and decomposed separately with the help of anaerobic bacteria.

 

Sludge is a semi-solid, residual material that is generated during the treatment of wastewater or industrial wastewater. It typically consists of a mixture of organic and inorganic solids, along with water and some dissolved materials.

In the primary settling process, the sludge is removed and decomposed separately with the help of anaerobic bacteria. During this process, the organic matter is converted into biogas, which can be used as a renewable energy source, and stabilized biosolids, which can be used for beneficial purposes such as land application.

Overall, anaerobic bacteria play a critical role in the treatment of sludge, helping to reduce its volume, stabilize its composition, and generate renewable energy and useful byproducts.