Over the past decades, the anaerobic digestion (AD) process has been employed as a potential medium to produce valuable resources from the waste-based feedstock. Moreover, the use of AD technology can generate not only resources, but it also creates an avenue for useful chemicals recovery to further use in commercial purpose, which is a part of the circular economy consortium. Volatile fatty acids (VFAs) are one of the most precious chemical feedstock that can be recovered from anaerobically digested effluent through the use of a pressure-driven membrane filtration process. In an effort to improve the recovery percentages of VFAs from anaerobically digested effluent, this study proposed a sustainable pathway by reusing the permeate effluent in the nanofiltration process. For this purpose, particles free feed solution was produced using the ultrafiltration process and sequentially subjected to the nanofiltration process in the presence of a 200-300 Da nanofiltration membrane. Each permeate was mixed with a known amount of fresh feed and continues up to 3 cycles to be improved the recovery percentages of total VFAs concentrations. Results indicated that recycling strategies could be a potential way to modulate the concentration of VFAs compounds.
The use of membrane reactor in wastewater treatment gained interest for the past years due to its high-quality effluent. However, expensive membranes and high operational costs due to membrane fouling limit the wide application of this process. Research on fouling control by combining membrane use with different techniques have been studied to address this challenge. This study particularly uses electrochemically-enhanced self-forming dynamic membrane bioreactor (e-SFDMBR). The main feature of the SFDMBR technology is that the biological filtering layer self-forms on a support of cheaper, inert coarse-pore membrane. This work focuses on describing the treatment performance of the bioreactor and the effect of lowering the current density and application period of electric current on the effluent quality and membrane fouling. Two systems of e-SFDMBR were operated and compared in terms of ammonium-nitrogen and orthophosphate removal and concentration of fouling precursors. The lower application period system (0.5 mA/cm2, 3 min ON/27 min OFF) posted 99.71% ammonium-nitrogen removal while the lower current density system (0.3 mA/cm2, 5 min ON/20 min OFF) achieved 99.68% removal. Both systems were able to completely remove phosphate and produce low concentration values of known fouling precursors.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.