Bioenergy / Energy from wasteProject Malabar Biomethane Injection Project
This report shares lessons related to the development of biogas upgrader specifications and community consultation.
The project uses low flowrates of excess biogas from the facility that would have otherwise been flared and high flowrates of biogas when a cogeneration engine is not operating. The minimum flowrate is limited to 30% of capacity of the compressors feeding the membranes but efficiency drops significantly below 50%, this is also generally the case for Pressure Swing Absorption (PSA).
The domination of low and high flows created a challenge for sizing the equipment as a lower maximum flow allowed for more low flowrates to be captured, but high flows represented a high portion of total flows so maximising what could be captured at the top end was also important. Furthermore, if the unit was not consistently operating there would be more gas lost and energy used during starts and stops which also presented issues for maintenance.