Norrmejerier
Transforming dairy waste into clean biofuel
Norrmejerier in Umeå is the first dairy in Sweden to close the production loop with its own biogas facility. A unique system uses whey and dairy production waste to generate biogas for fuel and heating. The result is lower oil consumption, greenhouse gas emissions and transport costs.
Effluent and waste into fuel
Built in 2005, the plant turns waste residues and effluent from dairy production into clean biogas that not only benefits the environment but makes the dairy more competitive too.
The system works by pumping filtered whey and waste water from the production line into tanks where a microbiological process breaks down the organic matter under oxygen-free conditions.
The digestion process produces biogas, which is then combusted in a gas steam boiler to produce high-pressure steam. The steam powers the dairy’s production machinery and provides heating and hot water.
Environmental benefits...
In total, the digestion process produces 35,000 kWh of energy per day and 10,000 MWh of biogas annually, with an additional 7,000 MWh generated by a heat pump. The sludge produced during digestion is transported to a nearby sewage treatment plant and used to manufacture sludge pellets, a filler material used in road building.
The biogas plant has reduced Norrmejerier’s annual oil consumption by 2,500m³ and cut annual emissions of CO₂ by 9,500 tonnes and of nitrogen oxide and sulphur dioxide by 9.3 and 3.9 tonnes respectively .
...and economic gains
The benefits are economic too, with Norrmejerier expecting to recoup its investment cost through energy savings and production efficiencies within 6-8 years.
The facility has cut the company’s transport footprint by the equivalent of 20,000 kilometres per year and also created added capacity for cheese-making, making the dairy more efficient and competitive.