ABSTRACT
Adequate and cost-effective treatment of wastewater is a more challenging task. In most countries, large-scale environmental initiatives have been taken, which resulted in the application of strict rules and regulations regarding the discharge of industrial wastewaters into the environment. A combination of physical, chemical, and biological processes is included in the conventional wastewater treatment processes, which are not only operated to remove solids and organic materials but also nutrients from the wastewaters. Preliminary solids settled at the bottom of the tanks are removed through sludge rakes, which fix the sludge to the central well and from there, it is pumped to sludge processing units. The microorganisms get attached on the surface of the supporting media, forming a biological film or layer where organic materials get metabolized by diffusing into the film. Tertiary treatment, more commonly known as advance wastewater treatment, removes specific wastewater constituents that were not removed by secondary treatment processes.
