Professor Hailiang Song and Dr. Yuli Yang published a research paper in Desalination (2020, 496, 114730)
By combining the merits of bioelectrochemical systems and osmotic membrane bioreactors (OMBRs), bioelectrochemically assisted OMBRs (BEA-OMBRs) can achieve simultaneous water/electricity recovery and salinity mitigation. One of the key challenges is reverse solute flux (RSF). The “negative effect” of RSF was turned into a “beneficial effect” by using a reverse-fluxed draw solute (DS) as a buffering agent or a carbon source supplement. The reverse-fluxed anions from the alkaline buffering DSs (NaHCO3 and PBS) stabilized the anolyte pH and had a positive effect on system performance, such as a high total Coulomb of 278.16–289.80C, a high recovered water of 261.64–277.80 mL, and a high COD removal of 90.91–91.61%. The reverse-fluxed cations from the acidic buffering DS (NH4Cl) promoted the accumulated ammonium to diffuse from the feed/anode to the cathode side due to the production of ammonia gas in the alkaline catholyte. The organic DS exhibited a lower RSF and a lower anolyte conductivity of 5.12–8.49 mS cm−1. However, the reverse-fluxed organic DSs (glucose and NaOAc) had a negative effect on the electricity generation due to carbon source competition. These results have demonstrated the advantages of the reverse-fluxed DS to enhance the system performance and to encourage further development of BEA-OMBR technology.