Danish CO₂ from agriculture becomes bubbles in your soda

When a biogas plant converts food waste and residues from agriculture into the green gas, biogas, 60% of the organic material becomes energy and 40% becomes CO₂. So far, it has been difficult to use the excess CO₂, and it is typically emitted back into the atmosphere. But when construction of the world’s largest biogas plant in Korskro near Esbjerg is completed, Strandmøllen, which shares the same location, will build one of the world’s first CO₂ plants which makes it possible to purify and condense excess CO₂ from the biogas plant.

“If we’re to meet the Paris Agreement targets and continue to be a green winner nation in the future, we must reduce our CO₂,emissions and bind the CO₂ we already have in circulation more effectively. This is the task we’re now undertaking. When the construction of the Korskro biogas plant is completed, we’ll take the 40% CO₂, which would otherwise have been emitted into the atmosphere, and use it for, for example, carbon dioxide in soda. This means that significantly less carbon dioxide needs to be produced using fossil energy, and it increases our possibilities of becoming green winners on the financial bottom line, the environmental bottom line and the climate bottom line,” says Ole Hvelplund, CEO of Nature Energy.

First CO₂ plant in Denmark

The partnership with Strandmøllen on producing green carbon dioxide is the first of its kind in Denmark, and comes after a summer in which several European beer and soft drinks producers have been struggling with a general shortage of CO₂ in Europe. 

Strandmøllen has been conducting research into purification of CO₂ from biogas plants for several years. This means that the CO₂ which has been through the company’s purification process is of a very high quality and can be used for, among other purposes, food production, dry ice and welding.  

“For a number of years, we’ve wanted to produce green CO₂, but it’s only now that biogas plants have become large enough to make it financially viable to establish a CO^₂ plant. Over the past few years, there has been a serious shortage of CO₂ in Europe during the summer months. With this new plant, Strandmøllen’s customers can look forward to much higher security of supply in 2019,” says CEO Alex Buendia from Strandmøllen.

The CO₂ plant in Korskro can produce up to 25% of the annual Danish CO₂ consumption. Denmark imports 65,000 tonnes of CO₂ annually. The imported CO₂ typically comes from fertiliser production based on fossil natural gas. 

The Korskro biogas plant is expected to be completed at the beginning of 2019, and the CO₂ plant will deliver the first bottles of carbon dioxide for the summer of 2019. 

How green carbon dioxide is produced

CO₂ is a natural by-product from biogas production. So far, the total CO₂ quantity from biogas plants has been too low to make extraction and purification viable. With the size of the Korskro plant, recycling of the CO₂ has, however, become profitable. Once the energy has been removed from the biogas, the remaining CO₂ is treated so that it acquires the desired purity. It is then stored in tanks or bottles until it is to be delivered to the customer. The customers then use the processed CO₂ instead of CO₂ from fossil energy. CO₂ is typically used in food production, slaughterhouses, market gardens, in soft drinks, as dry ice for cooling, in laboratories, for medical purposes in hospitals or for welding.

Facts