Continuing the all-Scottish theme, the ‘Kallista Helen’ was built by Ferguson Marine Engineering in Glasgow, with Macduff Ship Design’s innovative design reflecting the owner’s key requirements of minimal fish handling and maximum fish welfare.
Central to the vessel’s principles is a thermolicer designed and engineered by ScaleAQ and the first of its kind to be constructed in Scotland. A sudden rise in water temperature is a well-known method of killing lice so the thermolicer has been developed to bathe the fish in temperate water for a short period, causing the lice to die and fall off the fish, after which they are separated from the water using a 500-micron filtration system and collected to be removed from the marine environment.
Wider pipes with an overall straighter and simpler layout have been utilised to create a gentler experience for the fish. This method allows for de-licing up to 120 tonnes per hour of fish. The system allows for high levels of fish welfare and, as the process only utilises seawater, at the same time avoids pumping any chemicals into the sea. The system is at the heart of fish welfare.
The thermolicer is protected from the elements in an enclosed shelter deck to shield it from the elements. In turn, this provides a safer working environment for the crew as well as better operational efficiency and improved seaworthiness. Additionally, it provides a large area on the top deck for cargo and equipment, namely 3 x 40 ton/m cranes with a max outreach of 15.1m and able to all work simultaneously without any restrictions. This capability allows the vessel to operate the entire system including all intakes and return systems and the vessel will be less dependent on other workboats while on site. Incorporation of cargo space and container latching points in the top deck allows for the haulage of ISO tanks should it be required.
With the capacity to carry over 56m3 of fuel and over 40m3 of freshwater, the vessel has the ability to stay at sea for an extended period. The systems and machinery onboard have a high peak electrical load, resulting in a large engine room that spans over half the length of the hull. Propulsion is derived from 2 x Cat C32 main engines delivering a total power of 1300hp, the engines are paired with two ZF W1800 reverse reduction gearboxes. The shafts are connected to twin fixed pitched 1500mm propellors which are combined with low drag nozzles, supplied by Kort propulsion, to improve free running speed whilst maintaining a bollard pull of 15 tonnes.
The vessel is also fitted with high lift rudders by Wills Ridley and a 250 Kw hydraulic bow thruster by Kort Propulsion which ensures the excellent manoeuvrability required when working in and around the salmon farm. Two Cat C32 generators are also installed, providing 860kW each. These generators are used to power the thermolicing equipment, including the heating elements used to warm and maintain the temperature in the 22,000 Litres of seawater contained in the fish treatment system. A heat recovery system draws heat from the engines and transfers it to the de-licing system, saving on both fuel usage and carbon emissions. Smaller Cat C4.4 auxiliary engines are also used to power ships systems when the main generators are not in use.
Macduff Ship Design said, “We are thrilled to have been part of this project which showcases Scottish maritime strength with local businesses supporting each other, from initial design and conception through to the final deployment.”
Following completion of the vessel in Glasgow, the ‘Kallista Helen’ departed for Shetland for final outfitting with a short stop at her homeport of Tobermory. Following the installation of the thermolicing equipment, she will go on a long-term charter to Scottish Sea Farms.
Exhibitor: Macduff Ship Design Ltd