PROJECT DESCRIPTION
BACKGROUND
The textile industry is responsible for large water discharges that have an environmental impact. The sector consumes 93 000 million cubic metres of water annually (4% of the total water consumption of the world). Dyeing and textile finishing processes require the most water. Around 150 000 million garments are manufactured annually, producing 17 500 and 50 000 million cubic metres of wastewater. It is responsible for 19-56% of the total water consumption in the textile industry. Nearly one-third (30%) of the textile manufacturing industry is located in Europe. Technical solutions are available to reduce the high demand of for water.
The textile industry is also one of the most chemically intensive sectors, using more than 8 000 chemicals. The finishing processes use enzymes, softeners, resins and dyes, some of which are listed as emerging pollutants in the Directive (2008/105/EC). Most of them are disposed in the wastewater effluent, affecting chemical oxygen demand, biological oxygen demand, colour and conductivity. The wastewater also contains fibres and microfibres (plastic fibres smaller than 5 mm) that also have a negative environmental impact.
OBJECTIVES
The LIFE ANHIDRA project aims to reduce water discharges from textile finishing industry by up to 98% by re-using process water, thus saving resources and protecting the environment. The project will demonstrate water re-use in industrial washing machines over 60 days of operation, saving up to 21 000 m3 during this period and 123 408 m3 annually. This closed-loop process will reduce water consumption by 92% and energy use by 15%.
RESULTS
LIFE ANHIDRA demonstrated a sustainable, efficient, and scalable solution for drastically reducing water consumption and wastewater generation in textile finishing processes.
The technology was validated through a demo plant installed at a Portuguese textile finishing company, working for international brands, connected to real finishing processes in real production conditions (water outlet line of the washing machines).
Different types of wastewater from different processes (enzymatic, bleaching, neutralization) have been evaluated.
By combining mechanical and ultrafiltration solutions and boosted by ozone technology, this integrated system demonstrated the ability to reuse water in industrial washing machines for up to 60 consecutive days, achieving reuse efficiencies between 96% and 98%.
Throughout the project, 2,843.29 m³/year of water were treated, making it possible to recover 9,95 tons of textile fibers/year, and the primary energy consumption was reduced by 2,030.11 kWh/year.
The results confirm that the LIFE ANHIDRA system offers a significant environmental improvement over the conventional denim washing process. Despite the added energy demand for this process, the overall environmental performance is clearly more sustainable.
Key environmental achievements include:
- 92% reduction in water consumption
- 98% reduction in wastewater generation
- 44% reduction in carbon footprint
- reductions in turbidity (up to 97.8%), colour (up to 95%). and COD (more than 50%)
The ANHIDRA technology worked as expected, reducing water consumption and reusing the regenerated water in closed loop for garment finishing processes, contributing to the protection of natural resources and environment and fight against climate change. The system avoids the discharge of emerging pollutants, microfibres, and pathogens, contributing to the protection of aquatic ecosystems. The quality of the treated water is confirmed as suitable for reuse in industrial processes, especially in textile washing. The final products obtained by using regenerated water in garment finishing processes are similar to those using fresh water.
Different valorisation routes for fibre waste have been explored, mainly as pigment in textile and composite applications and in energy valorisation through methane generation. Three of them have been validated: a pigment-like material for dyeing/printing, an energy vector and a filling material for pieces, e.g., cloth hangers.
With a modular and adaptable design, ANHIDRA is ready for replication across diverse production environments, from small batch production to large industrial facilities.
Using ANHIDRA system in production conditions (working in continuous at a flow rate of 15 m³/h), water consumption savings would amount up to 123,408 m³/year in an industrial facility, being possible to recover 432 tons of textile fibres/year.
Recommendations for policy improvement and best practices for enhancing industrial water protection in the European Union are suggested, with a specific focus on the textile sector. Additionally, some best practices are proposed for adoption by the textile industry to achieve significant water savings and reduce environmental impact.
The ANHIDRA system is being patented internationally.
