Bio-engineers from the universities of Antwerp and Ghent have developed a new type of fertiliser based on bacteria derived from food industry waste flows.
In the Flemish food production industry quite a lot of fertilisers, like phosphor and nitrogen, are lost. Attempts have already been made to transform this waste into microalgae, which is apparently very useful as an alternative fertiliser. “Although the results were successful, it was 5 to 10 times as expensive as conventional fertiliser. We have now cultivated and mixed three types of safe microbes; primarily aerobic heterotrophic bacteria, purple bacteria and – to a more limited extent – microalgae”, explains researcher Siegfried Vlaeminck.
Professors at the University of Ghent set up a pilot project to test the mixture on several plant varieties, such as ryegrass, petunias, parsley and tomato plants. “We noticed that the microbial fertilisers works just as well as conventional organic fertiliser, and in some cases even better”, says Vlaeminck. “It may be more expensive, but because microalgae also protect crops against disease, we believe that this will be acceptable for the market.”
Now that the researchers have completed the pilot project, they are looking to scale up the experiment. A few hundred thousand tons will be needed to ensure a cost-efficient production and reliable supply, concludes Vlaeminck. Greenyard Foods has already professed an interest in participating in the experiment.
Source: HLN. Photo: Mario Bentvelsen.
Greenhouse builder Debets Schalke has a built one of the largest greenhouse for the cultivation of algae in the world in Austria. The greenhouse has a surface area of one hectare dedicated to the annual production of 100 tons of biomass derived from dry algae. When the full expansion of the greenhouse has been achieved in 2021 production figures will run to 300 tons per year.
The production of microalgae is a lucrative enterprise; the total turnover from the production of microalgae comes to billions of euros worldwide. Algae are relatively easy to grow and contain a high amount of high-quality fatty acids (Omega 3 & 6), natural colorants and valuable proteins.
The greenhouse built by Debets Schalke was tailored to the provide algae grower eparella with the facilities necessary for year-round production. A greenhouse with a post height of eight metres is exceptional, but necessary to enable the bioreactors that produce the industrial micro algae to operate to the best of their ability. Additionally, the greenhouse makes use of large ventilation systems to adequately regulate the extremely warm land climate in the greenhouse.
Versatile raw material
The microalgae grown by eparella are cultivated in 43,000 glass tubes distributed across 32 production chains: the bioreactors. It is possible to produce powdered algae of edible quality all year round by growing it in bioreactors. However, eparella does not use the micro algae exclusively for the production of foods and food supplements; eparella’s microalgae are also used as a raw material for cosmetics and medicines.
Because algae contain high-quality fatty acids like Omega 3 they are considered a sustainable alternative to fish oil. The production of algae does not create an imbalance in the existing ecosystems, as opposed to fisheries. eparella’s closed cultivation system ensures that the algae are grown in a pure and largely uncontaminated environment. As a result, the industrial microalgae are a clean raw material for sustainable products.
Text: Leo Hoekstra. Photo: Debets Schalke.