RECOMMENDATIONS

Further studies into the energy storage requirements as well as compositions required to successfully and economically use scrubbed biogas as an alternative to compressed natural gas (CNG), would expand on a biogas upgrading plants product line but lower capital costs, as the products produced from raw biogas can be increased. In South Africa, a large percentage of the population still rely on CNG and this is a market worth tapping into.

It is recommended that further studies into lowering the production cost by increasing capacities of the plant (and reroute this product gas to be utilised as a source of power in the

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plant) which can lower the energy requirements. Furthermore, preliminary results from the plant highlight that an excess of 400 MJ would lower the running costs substantially as the energy produced can be used to power the plant. This leaves it up to interpretation that the use of more energy-efficient equipment or eliminating the need of flash drums by utilising a multi- component distillation column with the above design, should be seen if it can be more feasible on a larger scale. In conclusion and for comparison, natural gas contains roughly 90% methane, has a calorific value of 39.50 MJ/m3 and biomethane with a methane content of more than 98%, has a calorific value of 36.00 MJ/m3, while the product gas produced by this process has a value of 36.42 MJ/m3. In order to achieve these higher calorific values, a study on utilising propane enrichment must be considered.

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APPENDIX