Proper product handling and efficient cooling are known to be the critical factors in preserving the quality and freshness of the catch. More than ever, consumers are demanding the highest quality seafood. To achieve this, initial rapid cooling of the product is required.
In addition to RSW and flake ice equipment, Highland Refrigeration has developed slurry ice machines that are capable of producing up to 70t of slurry ice per 24 hours.
Ice is harvested via BUUS standard horizontal ice machines. The flake ice enters a mixing chamber where seawater is added. The mixing process involves an agitator that converts the ice to slurry. From the mixing chamber, the slurry is homogenized and pumped to the desired location.
The viscosity of the mixture depends on the percentage of ice that exists in the slurry. 40% ice to water ratio is typically desired; however, the machine can produce the slurry at a wide range of ice to water ratio to satisfy the need. The lower the salinity of the seawater, the harder it is to make slurry reliably. Most slurry ice machines can only operate at 3% (by mass) salinity or higher, needing to add salt if the salinity is less. Some might be fishing near a mouth of a river or inshore where the salinity on an outgoing tide might be much lower than 3%.
Highland slurry ice machines operate with salinity as low as 1.5% using a unique mixing chamber design.
The slurry ice machines are manufactured for flexibility with equipment allowing them to produce standard flake ice by simply by-passing the slurry equipment. The slurry produced is 29 to 30°F, a few degrees lower than the melting point of freshwater ice. This speeds up the heat removal process. However, temperatures are not so low that there is a risk of partially frozen product.
Highland says its slurry ice system is extremely simple to operate with only one adjustment to set the viscosity of the slurry and an On/Off switch. Less than a minute after the machine is turned on, slurry ice starts to flow.
Testing onboard Jim Odlin’s Atlantic Trawlers, Highland received feedback to perfect the machine. “Two other manufacturers had to take their equipment back as it could not handle the low salinity seawater. With growing demand for quality, Highland slurry ice technology is providing the solution to our need for a reliable and easy to run system,” said Mr Odlin.
