Study published in the international journal "Resources, Conservation and Recycling"
The membrane technology group of the IMDEA Water Institute, has published a new paper regarding Life Cycle Assessment and economic analysis of the current state of the membrane recycling at pilot scale. This study published in the international journal of Resources, Conservation and Recycling, has as goal the comparison of pilots for end-of-life reverse osmosis recycling to nanofiltration (NF) and ultrafiltration (UF) to assess the most efficient and environmental favourable solution.
In this study two real pilots, called passive and active systems, were evaluated with Life Cycle Assessment methodology and 16 ILCD (International Life Cycle Data system) categories (reference method for the JRC) and a cost-effectiveness analysis.
The selection of the most eco-effective (passive system) allows the production of recycled membranes with a reduction of a 60% of the economic costs and between the 31-70 % of the potential environmental impact (depending on the environmental impact category) for the industrial implementation.
Photograph of the active system pilot (left), photograph of the passive system pilot (centre) and passive system design drawing (right). The images and virtual design were kindly provided by the Valoriza Agua Company
Furthermore, the techno-economic and environmental viability of the reverse osmosis membrane recycling, originally designed to treat seawater and brackish water into recycled NF and UF membranes was studied. This analysis, based in the substitution approach has integrated the performance comparison. It helped in the identification that the membrane recycling of brackish water membranes is more favourable than the one with seawater membranes. The comparative results between the commercial NF and UF membranes and the recycled membranes evidence a lower environmental impact around the 90-97%, depending on the impact category. These results with the low cost (€25.9-41.5/ module), would point to a greater environmental and economic competitiveness of the recycled membranes in applications of high replacement of NF and UF membranes such as landfill leachate or brine treatments.
Also, researchers have developed new indicators from environmental criteria such as minimum useful life through LCA result. These indicators point to a minimum life of 3 months to generate environmental credits from the recycling. The researchers emphasize that some of these membranes have already been validated for more than 1 year.
This study has allowed identifying hotspots and feasible solutions from BREF documents (Reference document of the best available technics of the Industrial Emissions Directive (IED, 2010/75/EU)) from other sectors as a reference to solve some common to other sectors. This approach aims to prevent the impact of recycling on subsequent industrial applications of recycling.
This work is the result of the synergies between the European project LIFE TRANSFOMEM and the national project INREMEM (Innovation and recycling of membranes for water treatment) and the collaboration of SACYR-SADYT and Valoriza-Agua to achieve sustainable membrane recycling systems.
Information about projects:
- LIFE TRANSFOMEM “Transformation of disposed reverse osmosis membranes into recycled ultra-and nanofiltration membranes”. Ref. LIFE13 ENV/ES/000751
- INREMEM “Innovation and recycling of membranes for water treatment”. Ref. CTM2015-65348-C2-1-R (MINECO/FEDER, UE)
- INREMEM 2.0 “Hybrid wastewater treatments based on recycled membranes with the objective of zero liquid discharge (ZLD)”. Ref. RTI2018-096042-B-C21 (MCIU/AEI/FEDER, UE)