Recycling of end-of-life reverse osmosis membrane modules into recycled ultra-and nanofiltration membranes for tertiary treatment

Reverse osmosis (RO) is the most employed technology for water desalination. Energy consumption and membrane fouling represent some of the major concerns in membrane technology because they increase the costs associated with treated water. Membrane lifespan is mainly correlated to the quality of the water and the operation condition and it is estimated that often membrane lifespan is 5 to 10 years. It has been calculated that 81,425 EoL membranes are disposed annually in Spain (1000 Tn). Considering that the 65% of the total worldwide desalination installed capacity (86.8 million m3 per day) uses RO membrane technology and that the average replacement rate is 15%, it can be extrapolated that 840,000 EoL membranes (14,000 Tn/year) are discarded every year worldwide. The constant disposal of EoL membranes in landfills and the con-sequent environmental impact has raised interest on looking for other alternative management routes. Among the different management alternatives (landfill, incineration, gasification, energy recovery, direct reuse and recycling), direct reuse and recycling is the most environ-mentally favourable option, whilst the current landfill disposal is the least favourable one. The technology for RO membrane modules recycling developed by the Spanish research institute can be applied to any EoL RO membranes installed in water treatment facilities such as desalination plants, wastewater treatment plants and industrial applications such as beverage concentration. Depending on the needs, EoL RO membranes can be transformed into NF or UF membranes to be reused for tertiary treatment. The service offers the possibility of conducting a full recyclability study that includes: • EoL membrane characterization by membrane autopsies, where the membrane module is opened to extract membrane coupons and fouling to diagnose the reason for its poor performance. • Study of EoL membrane process performance in terms of permeate flux and membrane rejection capacity. • Recycling process through the exposition of the EoL membranes to an oxidant compound at different exposure doses. • Surface characterization by several techniques such as SEM, AFM, ATR-FTIR and process performance study of recycled membranes. • Viability studies of recycled membranes for tertiary treatment at laboratory and pilot scale. The research center is looking for commercial agreements for the design, implementation and/or monitoring of membrane recycling: · Councils, community of municipalities, provincial councils, rural development associations; · Water Companies and Wastewater Treatment Plants in small municipalities; · Any company (textile, agri-food, etc) interested in treating their wastewater; · Any company interested in developing wastewater treatment projects in developing countries; And research and technical cooperation agreements to also improve both implementation and monitoring: · Associations or waste management industries; · Water resource managers; · Commercial membrane manufacturers and providers · Any company expert in ICTs.