April 2019

37 www.drivesncontrols.com April 2019 CONVEYORS AND MATERIAL HANDLING n Enclosed belts deliver food pellets safely on offshore fish farm H alf of the fish that we eat comes from freshwater and saltwater fish farms, such as those located close to the shore in Scotland and Norway. To cope with the growing demand from an expanding population, scientists and companies are now looking to operate fish farms in marine locations further away from the coast. As part of this drive, Norway’s Ministry of Fisheries and Coastal Affairs has awarded a development license to Ocean Farming, a subsidiary of SalMar, one of the world’s biggest producers of farmed salmon. The aim is to encourage new technologies that improve the well-being of the fish, while promoting sustainability and growth in difficult locations. Since November 2017, a 110m-diameter, 68m-tall, floating fish farm called Ocean Farm 1 has been operating off the Norwegian coast, investigating biological and technological aspects of offshore fish farming. The automated facility, which encloses 250,000m 3 of seawater, has the capacity to breed 1.5 million fish – about 8,000 tonnes – in 14 months. The semi-submersible structure, built in China, is designed to survive 15mwaves. It includes around 20,000 sensors and high- definition cameras that allow automated monitoring and feeding of the fish. Food in the form of pressed fishmeal pellets is transported by conveyor from supply vessels to the fish. If these pellets are put under too much pressure, particles can break loose from them and settle on the seabed, polluting the water and promoting the growth of algae. To avoid this, the pellets are enclosed within the conveyor system from the pick-up point to where they are delivered to the fish. The Sicon belts, developed for the application by ContiTech, can negotiate tight curve radii of less than 1m, as well as climbing the 13° gradients fromwhere the pellets are stored in the ships that deliver them, to the fish farm deck. One of the biggest challenges in developing the technology was finding the right compound for the belts. “The pellets are made of fishmeal and fish oil, so we developed a special rubber compound that is oil-resistant and meets the requirements of the fish feed industry,” explains David Grimes, managing director of ContiTech Scandinavia. “Cleanliness is crucial on-board the ship and at Ocean Farm 1. After all, we’re dealing with food here.” At the fish farm’s location in the Atlantic Ocean, the belts are exposed to extreme wind and weather conditions. ContiTech optimised the belt compound to cope with these conditions and to make them resistant to seawater. Using an enclosed conveyor system enhances safety for workers on Ocean Farm 1 and on the fish feed ships, because if oily fish feed fell on the floor, it could be a hazard.“Our belts increase well-being on-board the ships,” Grimes states.“They prevent odours and even help by enabling sailors to take off their shoes on the tween decks and in common rooms.” As well as the belts on the fish farm, five Sicon systems have been installed on-board the delivery ships and two in the fish feed factory. Other versions of the enclosed-belt technology are used to transport materials such as minerals, cement, diamond ore, biomass and fuels. Built-in sensors monitor temperature changes and load differences, allowing operators to intervene to avoid excessive wear and possible belt failures. n The global consumption of fish has almost doubled since the 1960s. In a bid to help meet this demand, the world’s first offshore fish farm has been installed off the Norwegian coast. Food is delivered to the farm’s 1.5 million fish by specially developed conveyor belts. Special enclosed conveyor belts are used to transport fish feed gently on the a pilot offshore fish farm operating in the Norwegian Sea. Photo: SalMar The Sicon conveyor belt system (above) is designed to transport sensitive materials. It consists of two fabric-reinforced profiles, each with a steel cord vulcanised in as tensile member. The profiles lie above one another to form a pouch.

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