(Photo: Puregas will convert methane gas from cow manure into a viable transportation fuel. Credit: Puregas Solutions)The existing anaerobic digester for a dairy operation in Oregon is getting upgraded to produce biomethane. Puregas Solutions, part of the technology group Wärtsilä, has been contracted for the renewable gas project.
Manure from more than 50,000 dairy cows will get processed into biogas at a rate of 3,100 cubic feet per minute using Puregas technology. From there, the renewable natural gas will get injected into a pipeline for use as transportation fuel in nearby California, according to the company.
Wärtsilä acquired Sweden-based Puregas Solutions last year. The company uses a process called CApure to convert raw biogas into biomethane and renewable natural gas. Puregas says that the order in Oregon is their first contract in the United States.
The project calls for installing gas conditioning equipment, and compression to 975 psi for pipeline injection. As part of the contract, the company will supply and install a hydrogen sulphide removal system.
Puregas says that their CApure CA80 biogas upgrading plant is scheduled to be completed during the first quarter of 2019, generating Renewable Identification Numbers under the federal Renewable Fuel Standard as well as credits under California’s Low Carbon Fuel Standard.
Once complete, the upgraded plant is expected to produce around 81 mmBTU of biomethane annually, which Puregas notes is equivalent to the annual energy consumption of over 15,000 households, 570 city buses, or 10,000 cars. In addition, the plant has an annual carbon dioxide reduction of 51,000 tons.
“This project, which essentially converts the methane gas from animal manure into a sustainable transportation fuel, is environmentally significant and an indicator perhaps of a future trend in biogas upgrading in the agricultural industry,” said Jan Molin, managing director at Puregas Solutions.
Earlier this year, four utilities invited dairies and agricultural companies in California to submit proposals for projects capturing and processing biogas from dairy cows to make natural gas. Although the biogas produced this way isn’t likely to offset much of the natural gas demand in the United States, a Michigan Tech University study published in 2017 found bigger potential to mitigate methane emissions.
