Economic and environmental assessment for integrated biogas upgrading with CO2 utilization in palm oil mill

In Malaysia, one of the source of biogas is from anaerobic digestion of palm oil mill effluent (POME). This biogas trapped is upgraded to biomethane by removal of CO2 and other unwanted components. Normally biogas upgrading process is designed not to further utilize the CO2 that can be raw material to produce useful product. Furthermore, CO2 released is a greenhouse gases that will cause environmental problems. By considering most of the POME treatment in palm oil mills is ponding system in Malaysia, microalgae CO2 utilization is suggested because the culture can be grown on ponding system of mill. The objective of this study is to assess the applicability of microalgae CO2 utilization in biogas upgrading technologies. In this study, economic and environmental aspect of microalgae CO2 utilization in biogas upgrading technologies are investigated. The profit penalty for the biogas upgrading technologies by applying microalgae CO2 utilization are in the range of 0.036 - 0.111 % and the CO2 reduction are in the range of 156,439,300 - 175,994,200 kg/y