Aemetis begins construction of biogas cleanup unit
The biogas cleanup unit at the Aemetis Biogas Central Dairy Digester project will produce RNG that meets utility gas pipeline standards and will be used as a transportation fuel.
Construction crews began site preparation and excavation this week, after which they will pour the cement foundation and install and connect process equipment. The unit will be co-located at the Aemetis advanced ethanol plant in Keyes, California, and will be directly connected to the PG&E natural gas pipeline. Plans are in place for an additional 32 miles of biogas pipeline that will connect over 30 dairies to the cleanup unit.
“The $12 million (€9.8 million) biogas cleanup and compression unit is scheduled to be operational by Q4 2021 to generate utility pipeline-quality RNG,” said Aemetis Biogas president, Andy Foster.
“Since September last year, the first two dairies in the Aemetis Biogas Central Dairy Digester Project have been operating, supplying biogas via a four-mile Aemetis-owned pipeline that is processed through a boiler system to produce heat and power for the Keyes ethanol plant.
“The new biogas cleanup and compression unit will allow us to supply fuel for trucks and other natural gas vehicles throughout California by injecting RNG into the utility gas pipeline, and via an on-site RNG fuelling station being built at the Keyes plant.”
Eric McAfee, chairman and CEO of Aemetis, described the construction as a “significant milestone” that will process the biogas delivered by the recently approved 35-mile pipeline.
“The negative carbon intensity RNG to be produced at the unit is scheduled to fuel trucks that deliver animal feed products from our ethanol plant to about 80 local dairies, and biofuel throughout California,” said McAfee.
“Our ability to fuel trucks with -426 carbon intensity RNG is a sustainable operating advantage for dairies and other members of the Aemetis network.”
The next phase of the project is due to complete a further 15 dairy digesters and 32 miles of biogas pipeline by the end of Q2 next year, generating around 440,000 MMBtu per year of biogas.