FISH FARMING TECHNOLOGY by Renate Hjørnevik, AKVA group, Norway
The latest innovation in cage technology under development is submersible cages for large-scale salmon production. AKVA group has been developing submersible cages since 1991 and has acquired great expertise, but as they have found - it takes time to develop this technology on the scale required to achieve efficient salmon production and a key part of the learning process has been large-scale trials.
GOOD CAGE SYSTEMS ARE ESSENTIAL IN ORDER TO ACHIEVE GOOD PRODUCTION AKVA group ASA’s subsidiary Helgeland Plast has manufactured plastic cages for more than 40 years. The first plastic cages were launched as early as 1974 at Lovund, and the start-up is a minor entrepreneurial miracle. The first plastic cages had a circumference of 40 metres and were a 1-ring cage with 160 mm diameter floating pipes, while supports and handrails rails had a diameter of 63 mm. In the 1980s’ the cages had becomes so large that a new 2-ring cage was launched. Polarcirkel Type 3 (2-ring with 200 mm diameter floating tube) and Polarcirkel Gigante (2-ring with 225 mm diameter floating tube), and several major deliveries were made to export markets such as Tunisia, Greece, Shetland, Canada, etc. In 1989 the sinker tube concept was developed, and as early as 1995-6 AKVA group supplied submersible cages to the export market. These were specially developed for submersion of biomass in the event of typhoons, oil spills, drift ice, algae, etc. As the first supplier to the aquaculture industry, Helgeland Plast was certified in accordance with ISO 9001 in 1994. In the 2000s’ the cages continued to grow in size, and since 1974 the company has supplied more than 50,000 cages all over the world. Developments have continued, and today cages as huge as 200-250 metres in circumference with floating tube dimensions of 630 mm are manufactured. The new 630 models also have new brackets with integrated attachment of bridle mooring lines, attachment of sinker tube, attachment for glass fibre pole for bird net and attachment of net. Developments have been fast-paced, and both material quality and design have been focus areas for AKVA group.
Lengthy experience with submersible cages
The latest innovation in cage technology under development is submersible cages for large-scale salmon production. As previously mentioned, the company has worked on developing submersible cages since 19956 and has acquired the basic expertise, but it takes time to develop submersible cages at the scale required to 50 | May 2017 - International Aquafeed