Electrodialysis with Bipolar Membranes for Valorization of Brines

Abstract

Several industrial processes, such as desalination or neutralization, generate brines defined as concentrated solutions of salts in water, usually NaCl, typically discharged in the vicinities of the desalination plant or factory. To reduce the environmental impact and promote the valorization of the wasted resources, alternatives must be sought. Among sustainable alternatives for the recovery of brines, the possibility of using Electrodialysis with Bipolar Membranes (EDBM) is of interest, because it allows recovering brines as useful acids and bases. This review focuses on the discussion of the technical aspects of the EDBM as a means to treat streams rich in NaCl from reverse osmosis desalination and industrial processes in order to complete the direct delivery of chemicals for self-supply. The main environmental issues associated with desalination brine disposal are presented. The state-of-the-art of valorization of brines by EDBM to acids and bases is completed. This work concludes with an in-depth discussion of the technical, techno-economic and economic barriers that prevent the widespread use of EDBM technology.

Keywords:

• Brines
• electrodialysis
• membranes
• reverse osmosis
• valorization

FUNDING

The authors gratefully acknowledge the funding for the projects CTQ2013-48280-C3-1-R-D and CTM2014-57833-R. Carolina Fernandez-Gonzalez also thanks the Spanish Ministry of Economy and Competitiveness for the FPI grant awarded BES-2012-053461.

Additional information

Funding

The authors gratefully acknowledge the funding for the projects CTQ2013-48280-C3-1-R-D and CTM2014-57833-R. Carolina Fernandez-Gonzalez also thanks the Spanish Ministry of Economy and Competitiveness for the FPI grant awarded BES-2012-053461.