Effect Of Membrane Selectivity And Configuration On Purity And Recovery Of Methane From Selected Landfill Bio-Gas
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Date
2021-07-01
Authors
Hiew, Yen Kei
Journal Title
Journal ISSN
Volume Title
Publisher
Universiti Sains Malaysia
Abstract
This thesis developed a simulation membrane model for methane enrichment from selected
landfill biogas. The simulation was used to investigate the impact of methane feed composition,
feed pressure, and stage cut on methane purity and recovery, as well as the impact of selectivity
on methane and carbon dioxide purity and recovery in biogas. The complete mixing model was
constructed in Mathcad and performance was optimized using Design Expert's Response Surface
Methodology. The optimization of membrane technology in methane enrichment of biogas from a
landfill in this project yield 100 % methane purity and recovery at CO2/CH4 selectivity of 623.12,
stage cut of 0.43 and feed pressure of 3.79 bar using membrane configuration type 1 at methane
concentration 0.53, CO2 permeability of 3871.00 barrer, CH4 permeability of 6.21 barrer, permeate
pressure of 1 bar. This exceeded the performance of the previous work without staging the
membrane process. At the methane composition of 0.60 in the feed gas, increasing the stage cut to
0.80 caused the purity of methane in retentate to be higher (100 %), but lower recovery of methane
(37.97%). Feed pressure did not seem to affect the purity and recovery of methane in retentate
significantly, but it caused carbon dioxide purity and recovery to slightly increase from 29.72 %
to 46.20 % at the permeate side. When the methane composition in the feed was increased to 0.60,
the 100 % purity of the methane in retentate was achieved whereas the recovery decreased to 37.97
%. The small error between previous work and the present study was 7 % and suggesting that the
mode is highly accurate in forecasting the purity and recovery of the two gas species using the
complete mixing model.