Double contact plate freezing is one of the fastest and efficient ways of freezing due to double contact of condenser and freezing product. They are known for ergonomic and cleaning-friendly design, fast freezing and maximum freezing speed. The process of freezing is following: product is placed in pallets and then ready pallets are placed between plated filled with coolant.
Freezing product is pressurized to improve contact with plates and efficiency of freezing process. Maximum heat exchange area is used and which positively affects the quality of freezing. Plate freezers are well-known for their efficient freezing and widely used in agro-industrial facilities.
Plate freezers are available both in vertical and horizontal types. Liquid refrigerant delivers to the evaporator plates from the special tank receiver. Uniform feeding of refrigerant to the plates excludes stagnant zones and provides intensive heat removal from the frozen product.
Using a pump for refrigerant circulating allows to obtain the same boiling point in plates compared with the non-pump equipment, regardless of their location (upside or downside). Therefore, you get the same temperature in frozen blocks regardless of what part of tile evaporator the freezing unit was.
The high velocity of the refrigerant in the plates provided by pump allows to avoid the accumulation of oil in the evaporator and reduce the intensity of heat exchange (to reduce the speed of freezing). Pump circulation scheme in freezers acceptable for medium and large capacities (above 10 tons per day). Plate freezers can be used when there is no need in saving original product’s shape.
Advantages of plate freezers
It is the most important factor determine the quality of the frozen product. The intensity of the heat and the freezing speed is proportional to the temperature difference. When products are placed into the freezing frames between plates they stay in direct contact with the evaporator, where the refrigerant constantly boils.
In air freezing refrigerant cools the air first, and the air cools the product in turn. In this case, air temperature in very good (and expensive) evaporators is higher than the boiling point by 5…6 °C. Therefore, while contact freezing the temperature difference between the product and the cooling medium is 5…6 °C higher than in air freezing.
Freezing speed while air freezing is closely connected with the speed of air blowing the product, which should be at least 3…5 m/s. To ensure these parameters air coolers require powerful fans which produce heat themselves. This heat must be compensated with an additional cooling capacity which increase the energy consumption.
Device and dimensions of freezers
Considered to be one of the most important factors determining the cost of capital construction or reconstruction.
Overall dimensions of air freezers with the same capacity as a rule have the volume several times exceeding the volume of locations with plate freezers installed. This is related to the fact that in the case of air-freezing, a sufficiently large number of products are simultaneously processed, and considerable amount of space must be left for proper air circulation.
At the same time, it’s necessary to consider the fact that production facilities where plate freezer is located have normal temperature condition and doesn’t require heat insulation of floor, walls, ceiling and installation of special doors, which significantly reduce the final cost in comparison with air freezers.
Plate freezer can be installed both on land and on fishing boats or vessels designed for processing products directly on the water.
Safety and operational requirements. The temperature maintained inside production facilities with plate freezer installed allows personnel to work without time constraints, providing both basic technological process and decontamination of rooms and equipment.
If you need detailed information on plate freezers, please send us your request or question by email@example.com or call us at (812) 346-56-66.