Well boats are used to transport live fish in modern fish-farming, both out to the sea-cages and from the cages to the processing plants. By using well boats the live fish can be transported over long distances in a controlled environment and the fish maintains its high quality during transportation to processing plants ensuring high quality and more consistent products.
The biggest challenge while utilizing well boats is to ensure that the storing facilities are hygienic and the water in the containers in which the fishes are housed, are changed periodically. Just like any other aquarium, the water in which the fishes are housed need to be changed and the right temperature needs to be maintained throughout. But while fresh water is transferred into the housing container, many fishing vessels dump the older water – unclean and contaminated – into the sea or the ocean. This leads to pollution of the entire oceanic ecosystem and potential adverse effects for the aquatic lives contained within it.
A mode to combat this challenge is to install filter systems to treat the waste-water before it is discharged or the water can be recycled after treatment, which allows the boats to go for long periods without discharging water.
The Bernoulli Filter can play an important part in the waste-water filtration system on well boats. By acting as pre-filter before UV-sterilization the Bernoulli Filter removes larger aquatic animals and debris, enabling the UV system to work effectively.
Case story: Patagonia Wellboat
To reach their target fish in the best physical condition and with less stress, Patagonia Wellboat has a fleet of seven ships specialized for the transportation of live salmon and trout. Patagonia Wellboat is a pioneer in moving services of live fish on board and made the first trip with live fish in 1993 by the ship Patagón I. All ships of last generation well boats have been built in the shipyards of ASENAV in Valdivia, Chile.
In 2012 Patagón VII, a well boat of 1500 m3 capacity, with the latest technologies for this type of vessel incorporated was built by Asenav for Patagonia Wellboat. This well boat has movables bulkheads in its fish holds, UV system and sophisticated sanitary control system.
The filter system to treat waste water at Patagón VII holds two Bernoulli Filters, BSG 300 with 300 micron filter baskets, capable of handling up to 2400 m3/h. The Bernoulli Filters are installed prior to UV sterilizer at the outlet of the fish tanks. By reducing the load particles the UV sterilisers will work more effectively. The treated water is then disposed in the ocean and the risk of contamination and spread of pathogens is minimized. The flushing water from the Bernoulli Filters is transported to a tank and there from pumped to a bag filter to remove sea lice before returned to the fish tank.
Facts and figures
Customer: Patagonia Wellboats
Location: Puerto Montt, Chile
Application: Prefilter UV disinfection
Filter model: 2 x BSG 300
Filtration: 0,3 mm
Operating flow: 2 x 750 m3/h
Design pressure: 6 bar
Operating pressure: 1,5 bar