Advances in Physicochemical and Biological Treatment of Textile Wastewater: An Applied Review of Methods, Technologies, and Costs

The textile industry is a major source of water pollution worldwide, including many countries in the Global South. Effluents from washing, bleaching, and dyeing contain dyes, heavy metals, surfactants, and other toxic compounds that threaten ecosystems and human health. Although wastewater treatment plants (WWTPs) reduce pollution, they face high costs, sludge generation, and limited removal of persistent contaminants. To improve performance, physicochemical, biological, and hybrid technologies have been developed. Coagulation-flocculation and adsorption are cost-effective but produce secondary waste. Biological systems such as enzymatic treatment and microbial fuel cells enable pollutant removal with potential energy recovery, though scale-up remains limited. Emerging methods such as nanofiltration, nanobubble technology, and electrochemical advanced oxidation processes (AOPs) provide higher efficiencies but face material stability issues. This review examines current technologies, their mechanisms, limitations, and prospects for achieving effective, economical, and environmentally sustainable textile wastewater management, supported by an assessment of effluent quality compliance and techno-economic feasibility. The ultimate goals of the review are to identify major research gaps and treatment processes that are effective, scalable, and implementable in real textile wastewater treatment installations and to propose concrete research directions that will enable the translation of promising laboratory results to full-scale implementation for textile wastewater treatment.