(473b) Applying the Attainable Region Approach to Biogas Production

Applying the Attainable Region Approach to Biogas Production

Ralph Farai Muvhiiwa*, Diane Hildebrandt, David Glasser, Tonderayi Matambo

Materials and Process Synthesis, College of Science, Engineering and Technology, University of South Africa (UNISA), c/o Christiaan de Wet & Pioneer Avenue, Florida Campus 1710, Johannesburg, South Africa

*r.muvhiiwa@gmail.com, hilded@unisa.ac.za, glassd@unisa.ac.za, matamts@unisa.ac.za

In this paper the authors present theoretical targets for producing biogas from one mole of glucose. The research reported here shows the relationship between the mass of substrate used versus the methane produced from a feedstock of glucose. The calculations undertaken to determine the production rates and environmental targets of the biogas production system were based on mass and energy balances as well as the second law of thermodynamics. These were applied to determine the limits of the process. The combined results were used to draw up an attainable region plot that shows the minimum work and energy requirements for sustainable biogas production. It shows that the process is hydrogen and enthalpy limited. The theoretical results show the region where no work and energy needs to be applied to the biogas process, and that neither temperature nor pressure in the reactor has much effect on the attainable region.

Key words: Biogas, Thermodynamics, Glucose, Attainable Region