Wärtsilä Gas Solutions, Biogas has supplied four biogas upgrading plants to inject biomethane into the Danish natural gas grid: Hemmet Bioenergy, Rybjerg Biogas in Roslev, Grøngas Vrå - and to date the largest single upgrading plant in the world, Sønderjysk Biogas.
Put into operation in April 2018, the Sønderjysk Biogas anaerobic digestion plant is located in Bevtoft - close to Vojens - and has the capacity to process over 600,000 tons of manure from local farms and additional organic waste each year.
The biogas production plant is owned and operated in a 50-50 % joint-venture between E.ON and Sønderjysk Biogas Invest A/S, which is owned by local farmers. Overall investment in the project has been over DK250m, and as part of the project, Wärtsilä Gas Solutions has delivered their largest Puregas CA Technology plant ever with a capacity of 6,000 Nm3/h of Biogas.
The plant in Bevtoft is expected to produce around 21 million m3 of biomethane per year. This is equivalent to the annual energy consumption of over 15,000 households, 571 city buses or 10,000 cars, with an annual CO2 reduction of 51,000 tons.
We chose Wärtsilä Gas Solutions as supplier for the biogas upgrading plant, primarily because the integration of the plant is a key aspect of the heating system of the whole production plant, and adds to the overall total energy efficiency. Puregas Solutions also has a well proven track record from previous projects with E.ON. The Puregas CA Technology solution gave the best value when considering both investment and operation over a 10 year period.
Wärtsilä Gas Solutions unique Puregas CA Technology recovers over 99.9% of the biomethane present in the raw biogas, by chemically absorbing the CO2 in the raw gas. The selective organic solvents used in this process are highly efficient, resulting in an end product containing more than 99% methane. The biomethane is of high enough calorific value to be directly injected into the natural gas grid without the need to enrich with propane saving significant costs.
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.
With more than 20 years of experience Wärtsilä Biogas Solutions provides fully integrated solutions for biogas upgrading and have over 30 plants already operating across Europe.
Wärtsilä Gas Solutions deliver several options for treating biogas, ranging from upgrading to biomethane (Renewable Natural Gas) for grid injection, compression for bioCNG, to liquefaction for bioLNG and fuelling infrastructure.