Performance and Evaluation of Wastewater Treatment Processes, State-of-the-Art Review

Water is a scarce commodity and there is the need to protect the available water resources from discharges of untreated wastewater. The supply of freshwater is limited and threatened by indiscriminate discharge of untreated wastewater effluents. Additionally, the discharge criteria of wastewaters are becoming stricter, according to the new legislation in force, in order to prevent environmental pollution and/or infection of drinking water sources. It is evident that more effective water and wastewater treatments are needed. Therefore the aim of this paper is to provide an overall description of wastewater treatment process. In developed countries, wastewater systems are well organized and cover most parts of the regions but this is not the case in developing countries. Various forms of wastewater treatment exist; however this study provides valuable information on waste treatment system that meets standard requirements before discharge into surface waters. Furthermore, the study was planned to generate information that could be used by wastewater treatment in order to develop or review an effective policy for wastewater treatment in meeting standard requirements for discharge of effluents into water sources.