The project has been completed. The methane content of the raw biogas ranged from 35 to 70.5 percent. Biomethane from food waste digesters had methane contents above 90 percent. Other targeted constituents include ammonia, alkanes, sulfur compounds, VOCs, siloxanes, metals, bacteria, pesticides, and others. The composition of biogas and upgraded biomethane produced in California depends on the feedstock and the design of the anaerobic digester. The tests conducted to date suggest that the composition of biogas produced at different facilities varies significantly. The findings have lead to additional work supported by CARB to further investigate particular chemical compounds identified by this study.
The researchers conducted a comprehensive set of measurements of biogas composition for thirteen different biogas/biomethane sample streams and a single natural gas stream. They derived sample streams from seven different production sources: two wastewater treatment plants, two dry green waste and solid waste facilities, one wet green waste and solid waste facility, and two landfills. [br /]
Key Project Members
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