BAKKAFROST SET TO BOOST CIRCULAR ECONOMY CREDENTIALS IN SCOTLAND

Bakkafrost set to boost circular economy credentials in Scotland with new system to turn by-product into fertiliser. Bakkafrost Scotland is set to boost its circular economy credentials at its flagship recirculating aquaculture system (RAS) facility at Applecross with a new cutting-edge treatment system which turns the by-product into fertiliser.

Scottish Environmental Protection Agency (SEPA) has granted the first Waste Management Licence in Scotland for a hatchery pyrolysis unit and Bakkafrost Scotland will build the new treatment system to create biochar from surplus produced at the RAS facility.

The surplus is a by-product of the wastewater treatment process, consisting of organic and inorganic solids held in water. The process dries the sludge and turns it into inert biochar which is known as a fertiliser and soil improver, refining the structure and water retention in soils. This process also ‘locks away’ carbon permanently.

In the first stage, hatchery ‘sludge’, roughly 97 percent water, is treated by going through a filter belt. The water content is reduced to about 80 percent and the dry matter content is increased to about 20 percent.

The next stage requires the license as it incorporates a pyrolysis unit which dries sludge at about 300°C, generating sludge pellets. These are then heated to 700°C without the presence of oxygen during a pyrolysis process. Heat is effectively absorbed and repurposed inside the system, increasing total energy efficiency. The end product is a biochar which is a material with a high stable carbon content.

Ian Laister, Managing Director, Bakkafrost Scotland, said:

“In a RAS facility, substantial quantities of unused ‘waste’ materials are generated, which must be separated from the water circulating back to the fish.

“Traditionally, that material has been considered waste, but technological advancements have opened the door to a more sustainable management process and that must be good news for helping protect our environment.

“All of this is very much in line with Bakkafrost Scotland’s sustainability goals and supports building a circular economy from farm to fork.”

The new project aligns with Bakkafrost Scotland’s commitment to play a leading role in the sustainable transformation of the aquaculture industry to ensure it is fit for the future with a significant investment programme over the next ten years designed to strengthen, grow, and transform the business.

Bakkafrost Scotland’s ambition for its RAS facilities is to reduce waste by 90 per cent, to use 100 per cent sustainable power and to reduce the water used in the process by 90 per cent. Hydro, solar, recycled material, and heat recovery systems will be used to reduce impact on the environment.