Potential upgrading of bio-refinery streams by electrodialysis

• Published in: Desalination 2017-08, Vol.415, p.20-28
• Main Authors: Luiz, Audrey, McClure, Dale D., Lim, Kylie, Leslie, Greg, Coster, Hans G.L., Barton, Geoffrey W., Kavanagh, John M.
• Format: Article
• Language: English
• Subjects: Bio-refinery streams; Electrodialysis; Organic-salt separation; Waste valorization
• ISSN: 0011-9164; 1873-4464
• DOI: 10.1016/j.desal.2017.02.023

Modern bio-refineries generate considerable volumes of wastewater that are highly coloured (5600–572,000 PtCo) as well as being concentrated in both salts (conductivities up 72.4mScm−1) and organics (up to 380gCODL−1). In this study, bench-scale batch electrodialysis was performed to examine the feasibility of separating salts from organics for a range of industrial biorefinery streams. High levels of salt removal (up to 96% for a lignocellulosic effluent) were possible with minimal organic losses (0.3–6.3%), while key performance parameters were highly encouraging (current efficiencies=69–104%; specific power consumption=0.44–1.59kWhkg−1 of salt recovered). Collectively, the experimental results obtained here showed the cost-effective potential of electrodialysis to separate salts from organics in complex bio-refinery streams at the industrial scale. •Electrodialysis was used to separate salts from organics in bio-refinery effluents.•High salt removals were possible (up to 96%) with minimal COD losses (up to 6.3%).•Current efficiencies were found to be between 69 and 104% after 1h.•Specific power consumptions were between 0.44 and 1.59kWhkg−1.•Study shows potential method to valorize bio-refinery waste streams.