Water recovery from brines and salt-saturated solutions: operability and thermodynamic efficiency considerations for desalination technologies
Citation:
Vane, L. Water recovery from brines and salt-saturated solutions: operability and thermodynamic efficiency considerations for desalination technologies. Journal of Chemical Technology and Biotechnology. John Wiley and Sons, LTD, , Uk, 92(10):2506-2518, (2017). https://doi.org/10.1002/jctb.5225
Impact/Purpose:
Water recovery from saline sources, such as seawater, brackish ground water, wastewaters, and industrial process waters, is necessary to meet municipal and industrial fresh water needs in many regions. In addition, industries are pursuing means to achieve zero liquid discharge (ZLD) to reduce their environmental footprint, while salt recovery presents a resource recovery opportunity. One unresolved challenge in desalination is the management of brine streams - the concentrated waste salt solutions remaining after water is removed from saline streams. In this article, the efficiency and practicality of different technology options for industrial and municipal brine treatment and salt crystallization are reviewed.
Description:
This review provides an overview of desalination technologies and discusses the thermodynamic efficiencies and operational issues associated with the various technologies particularly with regard to high salinity streams. When water is recovered from a saline source, a brine concentrate stream is produced. Management of the brine stream can be problematic, particularly in inland regions. An alternative to brine disposal is recovery of water and possibly salts from the concentrate. Due to the high osmotic pressures of the brine concentrates, reverse osmosis, the most common desalination technology, is impractical. Mechanical vapor compression which, like reverse osmosis, utilizes mechanical work to operate, is reported to have the highest thermodynamic efficiency of the desalination technologies for treatment of salt-saturated brines. Thermally-driven processes, such as flash evaporation and distillation, are technically able to process saturated salt solutions, but suffer from low thermodynamic efficiencies. This inefficiency could be offset if an inexpensive source of waste or renewable heat could be used. Overarching issues posed by high salinity solutions include corrosion and the formation of scales/precipitates. These issues limit the materials, conditions, and unit operation designs that can be used. Published 2017. This article is a U.S. Government work and is in the public domain in the USA.
URLs/Downloads:
DOI: Water recovery from brines and salt-saturated solutions: operability and thermodynamic efficiency considerations for desalination technologies
http://onlinelibrary.wiley.com/doi/10.1002/jctb.5225/abstract
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