Environmental sustainability assessment of different strategies for the treatment of wastewater from textile industry

Severe water consumption and highly polluted wastewater are the main issues of textile industries, which can affect environmental safety. Advanced oxidation processes (AOP) emerged as innovative strategies to enhance conventional wastewater treatments, for their strong ability to reduce chemical oxygen demand (COD) and pollutants. Among these, hydrodynamic cavitation (HC) stands out as a promising technique to minimize the chemical additive uses, thereby improving the process sustainability. A life cycle assessment (LCA) was conducted to compare four scenarios, traditional biological treatment, membrane treatment combined with AOP and HC used either as pre- or post-treatment to the biological process. The results showed that biological process followed by HC offers the lowest environmental impact. This is attributed to a configuration change (compared to HC as pre-treatment) that reduces energy consumption without compromising water quality. In the climate change category, one of the most relevant, HC as a post-treatment (scenario 4) reduces the impact by 94%, compared to HC pre-treatment (scenario 3). It also achieves around 30% impact reduction relative to biological treatment, while ensuring the highest water quality, with a 98% reduction in COD. This quality supports the potential for water recirculation within textile manufacturing. Furthermore, the possibility of water reuse offsets the environmental cost of producing high-quality water, with an average environmental credit between 440 (scenario 3) and 600 (scenario 1) m3-world eq, in the water use category. The superiority of the HC post-treatment setup was also confirmed from a performance standpoint, as it reduces the complexity of process management.