Sustainable Waste Water Treatment Technologies

Abstract

Nowadays, the environmental problems associated with residual colour in industrial effluents have posed a serious threat to many environmental scientists. The effluents from the industries have liberated wide variety of pollutants which can directly introduce into the natural water sources. The industrial sector usually consumes enormous amount of water for manufacturing the sportswear, fashion and luxury brands of clothes. In that, several hazardous chemicals were added for colouring and designing purposes which contains many organic and inorganic substances, ammonia, infectious microorganisms, detergents, heavy metals, pesticides and household cleaning aids. These water pollutants are toxic to fish and other aquatic lives and it is also harmful to humans. So, there is a need for removal of toxic pollutants from the industrial effluents. The methods for controlling the water pollution can be majorly classified into three steps: (i) Primary (screening, sedimentation, homogenization, neutralization, mechanical flocculation, chemical coagulation) (ii) Secondary (aerobic and anaerobic treatment, aerated lagoons, activated sludge process, trickling filtration, oxidation ditch and pond) and (iii) Tertiary (membrane technologies, adsorption, oxidation technique, coagulation and flocculation, electrochemical processes, ion exchange method, crystallization, Evaporation). This chapter describes a critical review of the current literature available on various wastewater decolourization techniques being applied to remove the hazardous chemicals from industrial wastewater.