FRAM FORUM 2018
Mass cultivation requires large amounts of CO2 gas – which can cost as much as 12 000 NOK per tonne. That is why the Faculty of Biosciences, Fisheries and Economics at UiT entered into an unusual partnership with Finnfjord AS. The company was sceptical at first, but eventually agreed.
“The notion that algae could clean industrial emissions sounded too good to be true. It was a pretty wild idea,” says CEO Geir Henning Wintervoll with a smile.
Diatoms use photosynthesis to convert carbon dioxide and inorganic nutrients into high-energy organic matter: algae biomass. To do this, they need light as an energy source. The UiT researchers usually cultivate algae in tank reactors, which take up much less space than standard photobioreactors. When the first reactor was set up at the smelting plant in 2015 and the researchers prepared to lead exhaust fumes through the water, they didn’t know what would happen. Would the algae tolerate these gases at all? DRAMATIC EXPANSION In 2008, Finnfjord decided to become the world’s first carbon-neutral ferrosilicon plant. They installed Norway’s largest thermal energy plant to convert excess heat into electricity. This allows the smelting plant to recover more than 30% of the energy used in production. The temperature of the seawater that passes through the plant and the composition of the gasses the plant emits are favourable for algae cultivation. The researchers inject flue gas into the algae tanks to produce algae biomass. The gasses dissipate in the water and are absorbed by the algae, which grow by cell division. The algae biomass is then separated from the cultivation fluids in a centrifuge. Algae have proven to be very good at absorbing these exhaust fumes, and the biomass qualifies as “clean” according to standards set by the Norwegian Food Safety Authority. But it has been a bumpy road.
“The reason we got much better results is that our method of cultivation runs counter to all the other cultivation initiatives. Our challenges have always been related to scaling up the biological and technological processes and making production profitable,” says Eilertsen.
RESEARCH NOTES
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ALGAE AND DIATOMS – Algae is a generic term for a variety of aquatic plants, from single-celled species to seaweed many metres in length. – Algae make up most of the earth’s biomass. All life in the sea is based on primary production by autotrophic microalgae. – Diatoms are a class of microscopic, single-celled algae. They are among the world’s smallest organisms. The class includes about 200 000 species. – Diatoms have lived on the earth for over 150 million years and are considered fossils. – Diatoms can be found in fresh water and salt water, in humid environments on land and in the polar regions. – Diatoms are one of the main components of phytoplankton in Norwegian seas and in other oceans. – Diatoms are the cause of the algae blooms that occur every spring in Norwegian coastal waters. – Researchers at Finnfjord only work with one type of diatom, which has been carefully selected and tested over time. The algae have been growing at the Tromsø campus for several years.