Chapter 2 - Wastewater Treatment Processes—Techniques, Technologies, Challenges Faced, and Alternative Solutions

Abstract

Wastewater treatment has been a major concern to the environmentalists. Common sources of contaminants are the metal pollutants that enter the aquatic environment through the discharge of different industrial effluents such as electroplating, textile, etching, milling industries, and so on. Most of these contaminants are carcinogenic agents and toxic. Therefore it is necessary to reduce the level of heavy metals in municipal and industrial effluents before their discharge to the environment. In other word the contaminants presented in an industrial effluent must meet certain standards of purity before they can be discharged into waterways. Depending upon the volume of wastewater, the employed technique can be different. There are different methods to remove/recover pollutants, including adsorption, precipitation, ion exchange, membrane separation, filtration, chemical oxidation, and biological treatment. In general, these methods can be classified as chemical, physical, and biological depending upon the nature of the effluent and the principle of operation and also the method of implementation. This chapter summarizes wastewater treatment methods and provides a concise chapter as a reference for researchers and environmental engineers.