Vinardell Cruañas, SergiAstals Garcia, SergiJaramillo, MartaMata Álvarez, JoanDosta Parras, Joan2022-07-222023-01-012021-01-010048-9697https://hdl.handle.net/2445/187942This research evaluated the performance of a lab-scale anaerobic membrane bioreactor (AnMBR) treating municipal sewage pre-concentrated by forward osmosis (FO). The organic loading rate (OLR) and sodium concentrations of the synthetic sewage stepwise increased from 0.3 to 2.0 g COD L-1 d-1 and from 0.28 to 2.30 g Na+ L-1 to simulate pre-concentration factors of 1, 2, 5 and 10. No major operational problems were observed during AnMBR operation, with COD removal efficiencies ranging between 90 and 96%. The methane yield progressively increased from 214 ± 79 to 322 ± 60 mL CH4 g-1 COD as the pre-concentration factor increased from 1 to 10. This was mainly attributed to the lower fraction of methane dissolved lost in the permeate at higher OLRs. Interestingly, at the highest pre-concentration factor (2.30 g Na+ L-1) the difference between the permeate and the digester soluble COD indicated that membrane biofilm also played a role in COD removal. Finally, a preliminary energy and economic analysis showed that, at a pre-concentration factor of 10, the AnMBR temperature could be increased 10 °C and achieve a positive net present value (NPV) of 4 M¿ for a newly constructed AnMBR treating 10,000 m3 d-1 of pre-concentrated sewage with an AnMBR lifetime of 20 years.35 p.application/pdfengcc-by-nc-nd (c) Elsevier B.V., 2021https://creativecommons.org/licenses/by-nc-nd/4.0/BioreactorsAigües residualsBioreactorsSewageinfo:eu-repo/semantics/article7037602022-07-22info:eu-repo/semantics/openAccess