Mora-Sánchez, J.F.; González-Camejo, J.; Noriega-Hevia, G.; Seco, A.; Ruano, M.V. Ultrafiltration Harvesting of Microalgae Culture Cultivated in a WRRF: Long-Term Performance and Techno-Economic and Carbon Footprint Assessment. Sustainability2024, 16, 369.
Mora-Sánchez, J.F.; González-Camejo, J.; Noriega-Hevia, G.; Seco, A.; Ruano, M.V. Ultrafiltration Harvesting of Microalgae Culture Cultivated in a WRRF: Long-Term Performance and Techno-Economic and Carbon Footprint Assessment. Sustainability 2024, 16, 369.
Mora-Sánchez, J.F.; González-Camejo, J.; Noriega-Hevia, G.; Seco, A.; Ruano, M.V. Ultrafiltration Harvesting of Microalgae Culture Cultivated in a WRRF: Long-Term Performance and Techno-Economic and Carbon Footprint Assessment. Sustainability2024, 16, 369.
Mora-Sánchez, J.F.; González-Camejo, J.; Noriega-Hevia, G.; Seco, A.; Ruano, M.V. Ultrafiltration Harvesting of Microalgae Culture Cultivated in a WRRF: Long-Term Performance and Techno-Economic and Carbon Footprint Assessment. Sustainability 2024, 16, 369.
Abstract
A cross-flow ultrafiltration harvesting system of a pre-concentrated microalgae culture was tested in an innovative anaerobic-based WRRF. The microalgae culture was cultivated in a membrane photobioreactor fed with the effluent from an anaerobic membrane bioreactor treating sewage. These harvested microalgae biomass was then anaerobically co-digested with primary and secondary sludge from the water line. Depending on the needs of this anaerobic co-digestion, the filtration harvesting process was evaluated intermittently over a period of 212 days for different operating conditions, mainly the total amount of microalgae biomass harvested and the desired final total solids concentration (up to 15.9 g·L1 with an average of 9.7 g·L1). Concentration ratios of 15-27 were obtained with average transmembrane fluxes ranged from 5 to 28 L·m2·h1. Regarding membrane cleaning, both backflushing and chemical cleaning resulted in transmembrane flux recoveries that were, on average, 21% higher than those achieved with backflushing alone. The carbon footprint assessment shows promising results as the GHG emissions associated with the cross-flow ultrafiltration harvesting process could be less than the emissions savings associated with the energy recovered from the biogas production from the anaerobic valorisation of the harvested microalgae.
Keywords
Anaerobic digestion (AD); cross-flow; greenhouse gas (GHG) emissions; harvesting; Membrane photobioreactor (MPBR); microalgae; ultrafiltration (UF); water resource recovery facility (WRRF).
Subject
Engineering, Chemical Engineering
Copyright:
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