Textile wastewater treatment options: A critical review

Abstract

Textile industry is one of the largest water-consuming industries in the world, and its wastewater contains many pollutants such as dyes, degradable organics, detergents, stabilizing agents, desizers, inorganic salts, and heavy metals. In Pakistan, most of the textile industries discharge untreated wastewater into water bodies without any treatment, which percolates into the groundwater posing a threat to the health and socioeconomic life of the people. Pretreatment, dyeing, printing, and finishing are the main steps in dyeing and printing process of textile industries. A large amount of wastewater is being generated by all these processes, which contains many pollutants like reactive dyes, chemicals, high chemical oxygen demand (COD), biological oxygen demand (BOD), and organic compounds. Research has been conducted since long to treat textile wastewater in an economical and efficient way. There are many processes for removal of polluted compounds from water that include physicochemical, biological, combined treatment processes, and other technologies. All over the world, ecological standards are gaining importance in every step of textile unit. Due to the strict implementation of environmental standards, it is important to adopt an eco-friendly model of textile industry that overcomes all flaws from its start to end product. The main challenge is to develop a design that can be considered as cost-effective and to substitute chemicals that are less harmful or can be easily treated. On the basis of wastewater characteristics and literature review, appropriate scheme of treatment processes was proposed.