Cost and energy needs of RO-ED-crystallizer systems for zero brine discharge seawater desalination
Name
Nayar et al. RO-ED-Crys. Zero Discharge Final PrePrint.pdf
Size
13.18 MB
Format
Adobe PDF
Checksum (MD5)
c0a96439d783e5bf84a83d875a2685a5
Author(s)
Fernandes, Jenifer
Al-Anzi, Bader S.
Nayar, Kishor Govind
McGovern, Ronan Killian
Lienhard, John H
Date Issued
February 2019
Journal
Desalination
Publisher
Elsevier
Citation
Nayar, Kishor G. et al. “Cost and Energy Needs of RO-ED-Crystallizer Systems for Zero Brine Discharge Seawater Desalination.” Desalination 457 (May 2019): 115–132 © 2019 Elsevier B.V.
Version
Author's final manuscript
Abstract
A zero brine discharge seawater desalination concept integrating reverse osmosis (RO), electrodialysis (ED) and crystallizer into a single system (REC) is presented. Analytical models were used to optimize parameters and minimize water production costs. Parameters varied were: the ratio of seawater to RO brine in the ED diluate channel, ED current density, ED diluate outlet salinity, electricity and salt prices, and RO recovery by adding high pressure RO (HPRO). Using only RO brine instead of only seawater in the ED diluate channel reduced water production costs by 87% from 27 to 3.5 $/m³ while increasing salt production costs 26% from 135 to 170 $/tonne-salt. The former was best for brine minimization, and the latter for salt production. Optimizing ED current density reduced REC costs by another 14% to 3.0 $/m³ while increasing specific energy consumption 26% to 12.7 kWh[subscript e]/m3, corresponding to a Second Law efficiency of 18%. Adding an HPRO stage was uneconomical as it increased specific costs 21%. A salt price of 104.5 $/tonne-salt will justify the cost of adding an ED-crystallizer. REC systems may be economically feasible in parts of the Middle-East. Producing other products such as Mg(OH)₂ or Br₂ may further improve economics. Keywords: Reverse osmosis; Electrodialysis; Hybrid; Salt production; Brine concentration; Seawater
MIT Department
Massachusetts Institute of Technology. Department of Mechanical Engineering
Terms of Use
Creative Commons Attribution-Noncommercial-Share Alike
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1016/j.desal.2019.01.015
