Each Gasum biogas plant produces biogas and recycled nutrients –fertilizer from the Lohja biogas plant in Finland can be used in organic farming

Did you know that besides biogas, Gasum also produces recycled nutrients in its biogas plants? For example, the recycled nutrients produced at the Lohja biogas plant in Finland that started operating earlier in the year are particularly suited for organic farming. The recycling of nutrients is still a fairly untapped resource. Enough phosphorus could be recycled from biomasses in Finland to sustainably fertilize all the arable land in the country.

Gasum is the largest biogas producer in Finland and each year recycles around 500,000 tonnes of biomass, turning it into a low-emission transport fuel, biogas. Besides biogas, Gasum’s plants produce various recycled nutrients. For example, the Lohja biogas plant, which opened in 2021 and it produces fertilizer suitable for use in organic farming. There is little of this type of fertilizer available regionally on the Finnish market.

Biowaste from shops and consumers together with side streams from the food industry are used to produce biogas and fertilizer in Lohja. Regarding recycling services, the plant serves in particular companies in the Helsinki region and increases the availability of fertilizers suitable for organic farming to farmers in the Lohja region.

“The Lohja plant is close to the Helsinki region and is home to a lot of organically farmed arable land, which benefits from recycled fertilizer. An advantage of recycled fertilizers compared to fossil fertilizers is the organic matter they contain and which plays an important role in maintaining the growing condition and weather resistance of arable land. Recycled fertilizers improve the soil fertility of arable land ecologically and thanks to the organic matter in the fertilizers, fields fertilized also sequester carbon better,” says Katja Alhonoja, Development Manager, Fertilizers and nutrients, Gasum.

Biomasses have enormous latent energy and fertilizer potential

There are currently many farms in Finland facing the problem of where to put manure containing phosphorus. These farms simply do not have enough arable land for all the manure they produce and so there is a high phosphorus loading in the fields. Using biogas production, for example, to recycle and process agricultural biomasses would enable more effective recycling of nutrients to different areas. This would reduce the unnecessary loading on arable land in individual areas.

All the same, there is still little manure used in biogas production. Alhonoja says that the aim going forward is to be able to utilize arable biomasses in biogas production and then return them to the fields. If biomasses, and the energy and nutrients they contain, can be used more efficiently we can speak of creating a truly resource-efficient ecosystem.

”There is enormous latent energy potential from utilizing biomasses in Finland. Gasum is a major processor of wastewaters and biowastes, but only a fraction of agricultural biomasses is utilized nationally. If all the phosphorus rationally extracted from biomasses were to be recycled, there would be enough to replace all the mineral phosphorus currently used on arable land in Finland,” Alhonoja says.

Fertilizers suitable also for industrial use

Besides being used in agriculture, recycled nutrients and fertilizers can replace fossil fertilizers used by industry. They can be used for example as a nutrient supplement in soil products used for landscaping and for covering landfills, and as a source of nitrogen in treatment plants in the forest industry.

“Recycled nutrients are an integrated part of the circular economy and their use contributes to enabling our customers to reach their sustainability goals. We are constantly identifying new applications for nutrients and developing our operations. A good example of our innovation is the ammonia water produced by our Turku biogas plant and which is used for scrubbing flue gases in the concrete industry,” says Alhonoja.

17.3.2021