Wetting challenges in treatment of raw textile wastewater by membrane distillation: A case study

This case study investigated the effectiveness of Direct Contact Membrane Distillation (DCMD) in treating real textile wastewater. Textile wastewater treatment presents a critical challenge in the field of environmental sustainability, requiring innovative approaches for its treatment to mitigate adverse impacts on ecosystems. DCMD emerges as a promising solution for the treatment and reuse of textile wastewater. However, the intricate composition of real textile wastewater represents a major bottleneck for the process, as the effectiveness of DCMD is influenced by numerous factors, complicating its application. In this study, experiments with an untreated sample demonstrate the detrimental impact of suspended solids on membrane performance. The application of simple pretreatment steps prior to DCMD, involving sedimentation and filtration, substantially enhanced the quality of the permeate, resulting in 100 % color removal, 99.99 % turbidity removal, and considerable removal rates for Chemical Oxygen Demand (COD) and Total Organic Carbon (TOC). Nevertheless, wetting remained a significant issue, as evidenced by the persistence of commonly used volatile organic contaminants and surfactants in the textile industry detected within the permeate. The findings in this case study reinforce that DCMD holds promise for textile wastewater treatment but emphasize the necessity of pretreatment and wetting mitigation strategies to fully unlock its potential. This research offers crucial insights for future MD applications in addressing the complexities of textile wastewater treatment.