Wärtsilä delivers and installs biogas upgrading solution in Denmark

In Denmark, Wärtsilä has engineered, delivered, and installed the biogas upgrading solution to a new biogas 17 tons per day liquefaction plant in Hjørring, Denmark. The contract was awarded to Wärtsilä in 2022, and the official start-up took place in June 2023.

The facility is one of two biogas plants owned and operated by GrønGas A/S in Denmark. The other plant, located in Vrå, also features a Wärtsilä biogas upgrading solution. The plant in Hjørring has an annual production capacity of more than 6,200 tons of bioLNG. Denmark is a world leader in biomethane development, and these plants are seen as being an important element in securing the country’s green energy future.

The Wärtsilä Mixed Refrigerant (MR) liquefaction unit alone has an exceptionally low power consumption of <0.75 kWh per kilogram of bioLNG liquified. This, in combination with Wärtsilä’s Puregas CA technology for biogas upgrading & polishing, with a total methane loss of less than 0.1 percent, makes it extremely energy efficient. The Puregas CA at Hjørring is equipped with the patented VAC (vacuum) option that offers greater flexibility in delivering heat to the upgrader, heat sources down to a temperature of 95 degrees C are possible to use.

The Hjørring plant transforms manure-based biogas into bioLNG, representing annual CO2 savings of approximately 41,000 tons when replacing natural gas.