Within three years, researchers and industries aim to establish a growth-concept that replaces parts of the problematic soy importation to Denmark. According to researchers, it is a ‘Keep It Simple Stupid’- project. The comprehensive soy import for Danish forage monopolises large areas of land in South America.
The objective is for Denmark to become independent from the import of proteins used in animal forage. In this context, plant breeders are working at full throttle to replace soy-forage with grass that has higher amounts of protein. Algae-experts estimate that they are now ready to work onshore.
Usually the algae production is maritime. However, if everything goes according to plan Danish chickens will, in a few years and on a trial basis, eat forage containing proteins from microalgae grown in a field located in Southern Jutland.
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‘’With this project, we are able to produce proteins in a sustainable way. If all goes well, we will be able to produce 15 to 20 tonnes of protein per hectare. This means that if enough biogas facilities existed, we would be able to provide protein for all of Denmark on just 30.000 hectare – which is not a lot’’, said Claus Felby, Professor in Biomass at the Department of Geoscience and Natural Resource Management at Copenhagen University.
A growing side current
Researchers and industries are cooperating on the project, Remapp, where they want to exploit side currents combined with excess CO2 and degassed slurry filled with nutrients. The slurry is derived from NGF Nature Energy’s biogas facility in Holsted, located in Southern Jutland.
Here, side currents are used for growing microalgae in long pipes or bags. When the algae are ready to be harvested, the proteins are separated and ready to be used in forage products.
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Currently, the biomass is used in fields, however, researchers believe that fields will not be affected by the project.
‘’Our results show that even though this is a big project, there will still be plenty of nutrients that can be used for agriculture’’, said Jesper Aaslyng.
A fraction of the side current
Algae biologist Malene Olsen from the Danish Technological Institute has used several years on creating the right algae mix with naturally grown algae from Danish nature, and the method is now certain.
‘’We have tested this on a small scale for three years, without being connected to a biogas facility but instead having liquid CO2 and slurry running through different pumps. It is time to upscale the process. Side currents are now to run directly from the biogas facility and into the production’’, said Jesper Aaslyng.
The first attempt is, however, a smaller one where only a fraction of the side current is used.
The biomass facility in Holsted annually produces 13 million m3 biogas, and nutrients and CO2 from a production of this size can provide around 4.700 tonnes of algae proteins annually, which corresponds to a value at approx. EUR 2.700.000.
‘’If we were to use the entire potential in Holsted, we would have to install a 275 hectare production. Therefore, this project only uses a minimal amount of the possible outcome. When the project is finished and we have proved that it works on a semi-large scale, Nature Energy will expand the production’’, said Jesper Aaslyng.
Enzymes break through the algae’s cell wall
The production process also includes the Department of Geoscience and Natural Resource Management at Copenhagen University, where Claus Felby and his team are working with the algae after they are harvested. The algae have a hard cell wall, which can be torn down by enzymes, and Felby and his team are experts in this process.
‘’The algae mass is centrifuged until it becomes a paste, which we then keep working on by using enzymes to break the algae in smaller pieces. The algae are then dried and after this, we have a forage protein product, which can be added to the chicken forage’’, explained Claus Felby.
The process is still under development, but according to Felby, the right types of enzymes have been found.
‘A lot of the technology, which we have already developed for bio fuels, can be directly transferred using the same principles. This is why it is a spinoff that technologies are connected’’, said Claus Felby
Allowing the algae to grow naturally
The project is running for four years and has a total budget of approx. EUR 3.500.000. The Danish Innovation Fund donated EUR 2.500.000 to the budget.
Operators assess that they are going about the protein production in a more clever way than former algae projects, where they have tried to manipulate the algae into doing something specific.
Around 50 percent of the algae consists of protein, and it is possible to produce algae almost all year. However, there may be a few months where algae cannot grow in the pipes without a little heating.