Land-based salmon production using RAS (Recirculation Aqua System) technology (RAS2) from Billund Aquaculture.
Billund Aquaculture is a global leader in building RAS facilities and has built more than 500 RAS plants, the majority being smolt facilities.
In our deployment of the system, water from the canal is pumped through filters and a water cleaning facility before being poured into the fish tanks. Some of the fresh water used in the smolt phase will then be used in a greenhouse to produce salad. The rest will be cleaned and re-used.
Eggs and hatchery
Columbi Salmon will buy fish eggs (ova) from an external supplier. The eggs are contained in shelves where temperate freshwater flows through the shelves.
Tanks for small fish
After hatching, the fish is moved to tanks, where they remain in fresh water until reaching 100-300 grams. In this phase, the smallest fish are called fingerlings,while the larger fish are referred to as smolt.
The grow-out stage corresponds to the period when the fish in traditional farming are moved from fresh water on-shore, to the ocean. Meanwhile, in our system the fish are transferred to the largest grow-out tanks.
Brackish water from the canal is pumped into large tanks and 99.9% of the water is re-circulated in a recirculating aquaculture system with various filters. The residual sludge and feed waste are removed and used in the production of biogas.
When the fish reaches its target weight (4-5 kilos), it is transferred to the primary processing plant, which is situated next to the largest grow out tanks. The fish is slaughtered, and gutted salmon, including the head, is packed in boxes, chilled and transported to consumers.
Salad production based on recycled water
The fresh water from the fingerling/smolt phase is normally taken out and cleaned for particles and nutrients. In our system, some of this water will instead be transferred to a large greenhouse (aquaponic) which has the capacity of growing up to 4,000 tonnes of salad annually, without using a single gramme of soil.
From one kilogramme (kg) of fish feed we can produce ten kg of food; one kg of fish and nine kg of salad. Moreover, initial calculations indicate that the salad may bind 2-3 times more carbon than is emitted in the process of producing the fish at this stage of the production.