Flake Ice Machine: What It Is and How It Works

What Is Flake Ice Machine

A flake ice machine makes dry and supercooled small ice, which is flat and has an irregular wafer shape.
An ice flaker or ice flake making machine sprays or pours water onto a cooled surface, like a cylinder or drum.
The water freezes on the surface, forming thin ice sheets (2-3 mm thick).
A scraper removes the supercooled ice and cuts it into small pieces that look like pieces of glass.
The ice pieces usually fall directly from the drum into a cooled compartment for storage.
The cooled cylinder can rotate in a vertical or horizontal plane.

Compact-Sized Flake Ice Makers

A compact-sized flake ice maker is designed for onboard ice production.
It is different from the normal drum style configuration by North Star Ice Equipment Corporation and produces flake ice in a rotating subcooled evaporator disc.
Ice is collected from both sides of the disc with adjustable scrapers.
Due to its compact size and lightness, it can be used in fish warehouses on boats 12 to 16 meters in length.
On smaller ships, it is often mounted on the deck.

Chip Ice: A Variation of Flake Ice

Chip ice is made in an ice flaker machine by draining water into an ice-making roller surrounded by an evaporative coil.
The water freezes in the cylinder at an evaporation temperature of -12 to -30 °C and is removed by a screw that rotates inside the cylinder, pushing the ice upwards.
The ice is pressed at the top of the cylinder, further frozen, and expelled from the top.
The temperature of chip ice is -0.5 °C and its average thickness is 7-8 mm.

Installation on Fishing Vessels

Flake ice machines are usually mounted on the deck, so the produced ice can be discharged directly into the fish hold through a small cover.
Drum-type ice makers designed for fishing boats have an ice discharge port below the drum center, which can be installed with a special cover.
Depending on the machine’s location and the manufacturer’s recommendations, some form of screening or cabinet may be required to protect the control panels or other parts of the unit.

Under-Deck Installation Problems

Most machines rely on gravity to feed ice into storage boxes after it is removed from the hopper.
This requires large fishing vessels with sufficient height to the deckhead to provide space for machine installation and to allow gravity feed to a collection area or storage pens.
Flake or shell ice machines may require a conveyor or auger for larger containers, but in most cases, the paddle crew transfers the produced ice to the storage items as needed.

Advantages and Disadvantages of Flake Ice

Main Advantages of Flake Ice

Efficient Heat Transfer: Flake ice has a larger heat exchange surface compared to other types of ice, making the heat transfer between fish and ice faster and more efficient.
Overcooled Efficiency: Since flake ice is slightly overcooled (-5 to -7 °C), it can release 83 kcal per kg when melted from ice to water, providing slightly more cooling than other types of ice at 0 °C (80 kcal per kg).
Ease of Storage and Transport: When adequately designed, supercooled (-5 °C) insulated storage is provided, making it easy to store and transport.
Compact Plant Size: The plant is small and compact, taking up less space than block ice plants.
Quick Ice Production: Ice production starts very shortly after starting the machine, allowing for almost “ice on demand”.
Immediate Usability: The ice is ready for use immediately after production, with no need for further crushing.

Disadvantages Compared to Block Ice

Complex Maintenance: The facility is less robust and more complex, requiring qualified engineers for maintenance.
Faster Melting: Ice melts faster due to its high surface area.
More Storage Space Required: For the same weight, flake ice requires more storage space.
Weighing for Sale: Produced ice needs to be weighed before sale rather than being sold by the unit.

Flake Ice Plant Installation

Container Coverage: Like block ice plants, flake ice plants can be covered in 20 and 40 ft containers, depending on the capacity of the necessary ice makers and ice storage systems.
Easy Setup: These units can be built to only need connection to a power and water source. With some modifications, they can be installed on very large fishing boats. However, these ship units are beyond the size range of the ships examined in this publication.
Large Capacity Models: Large capacity models for freshwater flake ice production are also available for terrestrial installations, producing 10 to 100 tons of ice with multi-coating systems. These models have a complete ice maker unit mounted on an insulated container used as an ice tank.
Technical Characteristics: Technical characteristics and features of some typical coated leaf and chip ice plants are provided in the Table.

Technical Features and Uses of Container Flake/Chip Ice Plants

Typical Technical Features of Container Flake/Chip Ice Plants

Compressed Small Ice Blocks: It is possible to produce small or flake ice blocks using block compacting machines when ice needs to be transported over long distances or when there are preferences for block ice in some fisheries.
Production and Installation: These machines press small ice (leaf or chip ice) into blocks of standard sizes and can be easily installed in small shore ice facilities.
Usage on Fishing Boats: These compressed small ice blocks can be used on fishing boats, offering the advantages of traditional block ice.
Suitability for Tropical Fisheries: They may be suitable for tropical developing fisheries, where ice melting rates are high and fishermen are accustomed to processing ice blocks from older ice plants.
Ease of Cutting: Compressed small ice blocks are easier to cut into smaller pieces when needed.

Conclusion

Flake ice machines, whether traditional drum types or compact-sized models, offer efficient cooling and immediate usability, making them ideal for various applications, including fishing vessels and shore facilities. While they require more storage space and specialised maintenance, innovations like compressed small ice blocks extend their utility, especially in tropical fisheries. Overall, flake ice plants provide versatile and effective solutions for ice production and storage needs.

What Is Flake Ice Machine | How It Works