Biogas Upgrading Plant

The Puregas CA process recovers more than 99.9% of the biomethane present in the raw biogas. The process separates the CO2 from the biogas by a process of chemical absorption. The selective organic solvents (Amine) used in this process are so efficient that the end product can contain more than 99% methane and is suitable for vehicle fuel or to be injected into the natural gas grid. As the final product is so pure there is often no requirement to enrich with propane. Siloxane removal is extremely efficient with contents of less than 0.05 mg/Nm3, which is the lowest detectable level for today’s instruments.

Unlike other technologies the Puregas CA process is highly tolerant of changes to the raw gas composition resulting from changes in feedstocks.

    99.9% Methane Recovery

    Puregas CA technology achieves the highest methane recovery, reducing methane slip to below 0.1%. There is no additional cost or energy requirement associated with treating the tail gas and harmful emissions to the environment are avoided.

    The long life, biodegradable organic solvents used in the Puregas CA process are not susceptible to changes in gas composition and form part of a closed-loop system where water consumption is kept to a minimum.

    • 99.9% methane recovery
    • Greatest life cycle profit
    • Lowest operational cost
    • Local service support
    • 24/7 remote monitoring
    • CO2 revenue stream
    • The greenest process
    • Integrated Solutions

    Integrated Solutions

    Availability guarantees of individual component parts of the biogas plant will not provide expected long term returns alone, particularly if the entire facility is not integrated to work as one. A biogas plant is the sum of several critical components, each interdependent, and the performance of the plant is driven by how well those components interface.

    Wartsila Biogas Solutions work with our customers to ensure our offering optimises performance across the entire biogas plant.

    The Puregas CA process includes a unique heat recovery option. Energy is recovered from the biogas upgrading process and fed into the anaerobic digestion by pre-heating the substrate. Compared with other biogas upgrading techniques, CApure heat recovery reduces the need for electric power, which can reduce energy cost by up to 50%.

    Additional value can be derived from the pure CO2 stream produced as is it removed from the biogas. This CO2 can be captured and used for propagation in glass houses, as a cooling agent or in general industrial applications.

    Case studies

    Innovation in Biogas Upgrading

    Biogas solutions providing flexible, cost effective, renewable energy to off grid customers tackling fuel poverty

    Read more »

    Biogas is Booming in Denmark

    Wärtsilä have recently supplied four biogas upgrading plants to inject biomethane into the Danish natural gas grid

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    Europe Needs More Biogas

    Wärtsilä have recently supplied four biogas upgrading plants to inject biomethane into the Danish natural gas grid

    Read more »

    Press releases

    Related products

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