CFD Modeling of Anaerobic–Aerobic Hybrid Bioreactor Landfills
Publication: International Journal of Geomechanics
Volume 18, Issue 7
Abstract
Anaerobic–aerobic hybrid bioreactor landfills, operated in a specific way that combines the benefits afforded by both anaerobic and aerobic processes, can significantly enhance the degradation of municipal solid waste (MSW) and the recovery of energy. The present article describes an application of computational fluid dynamics (CFD) to the numerical simulation of subsurface leachate recirculation and aeration systems in hybrid bioreactor landfills. The objective of the study was to model and investigate the hydrodynamic and biochemical behavior within a hybrid bioreactor landfill. The results indicate that the suitable transition time that ensures that the most methane potential has been exploited and that the hybrid landfill changes to aerobic conditions to shorten the stabilization process effectively is when 70–80% of methane potential has been exploited. A relatively small injection pressure is suggested in the initial stage of aeration for MSW with small permeability, and the injection pressure can be raised after the pore pressure dissipates and leachate flows out of landfills smoothly. Results also show that a reasonable method of intermittent leachate recirculation during aeration is to start it when the water content decreases to the minimum value required for the hydrolysis reaction and stop it once the maximum hydrolysis rate is reached and that the configuration of the group-well system has an obvious effect on the leachate volume, whereas it appears to have a relatively small effect on the air volume.
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Acknowledgments
Much of the work described in this article was supported by the National Natural Science Foundation of China under Grants 41661130153 and 41572265, the National Program for Support of Top-Notch Young Professionals, the Shuguang Scheme under Grant 16SG19, and the Newton Advanced Fellowship of the Royal Society under Grant NA150466. The authors greatly acknowledge all of these financial supports and express sincere gratitude.
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Published In
International Journal of Geomechanics
Volume 18 • Issue 7 • July 2018
Copyright
© 2018 American Society of Civil Engineers.
History
Received: Aug 2, 2017
Accepted: Jan 25, 2018
Published online: May 1, 2018
Published in print: Jul 1, 2018
Discussion open until: Oct 1, 2018
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