Abstract
The drive for finding alternative energy to
supplement fossil based fuel within the South African energy
sector has led to research on waste to energy in particular biomethane
as vehicular fuels. Biogas is produced from the
anaerobic decomposition of organic matter with 40-70% vol. of
methane. Biogas if upgraded, by removing the non-combustible
component, can achieve 99% methane concentration which
makes it a potent vehicle fuel and a direct substitute to natural
gas. In this paper, a biogas upgrading plant operation that uses
gas permeation technique for methane enrichment of biogas
was studied and simulated. The effect of recycling permeate
stream on methane recovery was studied. Recycling of the
permeate stream improved the methane recovery of the
simulated process by 18%. The overall methane recovery of the
simulated process is 81.23%.