Valmet will supply a flue gas condensing plant to Helen Ltd’s Vuosaari C bioenergy heating plant in Helsinki, Finland.
The new bioenergy heating plant will feature very high energy efficiency, as the heat from flue gases will be recovered to increase district heat production by 69MW with Valmet’s advanced environmental technology.
The order is included in Valmet’s orders received of the first quarter 2020. The value of these types of orders is approximately between EUR 20–30 million. The flue gas condensing plant will be handed over to Helen in December 2022.
“Our company’s target is to be carbon neutral by 2035. As the flue gases after combustion are led to the condensing plant, it is possible to utilize the fuel to its fullest. The heat recovery at the Vuosaari plant will increase plant efficiency to about 122 percent based on the fuel’s effective heating value,” says Antti Saikkonen, Project Director, Helen Ltd.
“The exceptionally high heat recovery is achieved by using absorption heat pumps to cool down the scrubber water and by cooling the flue gas going into the stack to below 12 Celsius. The absorption heat pumps use low-pressure steam as the driving media instead of electricity,” says Risto Hämäläinen, Director, Environmental Systems, Pulp and Energy, Valmet.
Valmet’s delivery consists of a flue gas condensing plant and condensate treatment equipment, including a boiler make-up water production system.
Flue gas from the bioenergy heating plant’s circulating fluidized bed (CFB) boiler is recovered by condensing flue gas moisture in a wet scrubber. Flue gas moisture is increased by moisturizing the combustion air going into the boiler. Heat recovery increases district heat production by an additional 69 MW, which is over 30 percent of the fuel heat input based on the effective heating value.
Flue gas condensate from the process is treated and utilized as raw water at the boiler plant and as boiler make-up water after demineralizing.
Helen Ltd. is one of the largest energy companies in Finland with more than 500,000 customers.
The company produces and sells electricity, district heating and district cooling. Furthermore, it offers solutions for regional and renewable energy, smart housing and electric mobility. Helen’s target is to achieve 100% carbon neutrality in its energy production in 2035.