General Overview of Wastewater Treatment Process with Special Focus on Secondary Treatment Method


  • Krishpa Adhikari
  • Dipendra Wagale
  • Pedro Arce
  • Robby Sanders


Wastewater is used water that comes down the drains from buildings such as household, factory, school, or offices and includes sources like showers, sinks, dishwasher, toilet, etc. It contains substances from various sources including organics, medicine, and several other substances like toilet paper, cleaning & personal products that are harmful to the environment. It also contains diverse trophic level of microorganisms such as protozoans, fungi, and varieties of bacteria (aerobic, anaerobic, and facultative). Therefore, a treatment facility needs to be equipped with several processes and unit operations so that a complete decontamination can take place before water is released to the natural environment. Each unit operation in a wastewater treatment plant (WWTP) is associated with mechanical, physical, biological, and chemical aspects of cleaning.
This contribution is focused on reviewing these general cleaning processes and operations and identifying connections with fundamental principles in engineering. Thus, we are looking for appropriateness of employing more effective and efficient variations associated with the biological processes (activated sludge). The aim is to develop an environment to mimic the naturally occurring microbiology and biochemistry in the human system during the metabolic breakdown of these chemicals and biopharmaceuticals. The secondary treatment is identical to a metabolic type of biological reactor that can be modelled and optimized. The targeted outcome is to identify the key factors controlling the metabolic degradation and make potential observations helpful to increase the degradation efficiency. Our study could be potentially useful for the design of a more efficient and better maintained treatment.