ADVANCING SUSTAINABLE TEXTILE DYEING SLUDGE MANAGEMENT: A COMPREHENSIVE REVIEW OF CO-PYROLYSIS AS AN INNOVATIVE THERMAL TREATMENT FOR CIRCULAR ECONOMY INTEGRATION AND ENVIRONMENTAL IMPACT MITIGATION

Abstract

This literature review critically discusses sustainable management techniques for textile dyeing sludge (TDS), a chemically toxic waste generated in huge quantities by the textile industry, leading to extensive environmental damage by chemical pollution, heavy metal toxicity, and excessive water and carbon release. The primary objective is to estimate the prospects of pyrolysis and co-pyrolysis as advanced, sustainable treatment methods for TDS out of available conventional methods, as part of the broader framework of circular economy strategies. Through a systemic approach, the study combines peer-reviewed research, and industry data to analyze and contrast biological, conventional thermal, and pyrolysis-based treatment technologies. Key findings indicate that pyrolysis and co-pyrolysis successfully reduce sludge volume, stabilize toxic components, and convert waste into useful commodities such as biochar, syngas, and bio-oil, optimizing resource recovery and waste valorization. Compared to biological processes, pyrolysis has enhanced contaminant immobilization and lowers environmental impact in various analyses. Co-pyrolysis, simultaneous thermal treatment of TDS with some other biomass or waste streams, achieves optimal energy recovery efficiency and lower emissions, enhancing circular economic ideas through closure of material loops and industrial symbiosis. The review has recognized pyrolysis as an economically and environmentally sustainable method for treating textile sludge, and co-pyrolysis contributes more to this with enhanced waste valorization and efficiency. These technologies are critical for guiding the textile industry towards green, circular production processes with less ecological harm while promoting economic resilience.