Optimization of Energy Consumption in a Wastewater Treatment Plant: An Overview

Wastewater Treatment Plants (WWTPs) play a crucial role in maintaining ecological balance, a cornerstone of environmental health for thriving biodiversity and undisturbed natural processes. This balance is crucial for the sustainability of ecosystems, directly influencing human health, biodiversity, and the overall quality of our natural environment. WWTPs contribute to this equilibrium by efficiently removing pollutants and harmful substances from wastewater, thus averting the degradation of water bodies that are essential for numerous ecological processes. WWTPs encompass multiple stages of wastewater and sludge treatment and are significant energy consumers globally, especially in secondary treatment, particularly the activated sludge method which is the most common method. With an upcoming directive from the European Union aiming to reduce energy consumption in WWTPs, this paper focuses on a literature review examining global practices implemented across all stages of WWTP treatment processes. It summarizes the key points of each study, focusing primarily on the outcomes of each application. This document concludes with an in-depth review of each study and provides general conclusions for each group of studies. The objective is to identify methods that have effectively reduced energy consumption and enhanced the overall energy efficiency of WWTPs. The main conclusions indicate that the studies encompass a wide range of applications that achieve significant reductions in energy consumption. However, additional testing of these applications in more diverse operating environments through trials could further enhance their reliability and increase acceptance among WWTP operators.