Saltwater freezer is an ideal choice for quickly freezing shrimp, whitebait, squid, sardine or similar products after fishing. These aquatic products can be frozen to -12-14 ℃ within 7-10 minutes after spraying sodium chloride through tunnels in perforated frames. Subsequently, the product enters a -35 ℃ air-cooled tunnel and is further frozen to below -18 ℃.
Saltwater is the most effective and economical way to freeze aquatic products. The heat transfer speed is fast, and the freezing time is reduced to a surprising extent. Fibers and cell walls do not rupture during freezing. The final frozen product has a good appearance and a small dehydrated weight. This product will not lose its nutritional content and maintain good sensory quality and a fresh appearance.
system composition
The system consists of six parts
1. The feeding end is equipped with a feeding conveyor belt. The conveyor belt with baffle is made of PE material. The belt width is 1800mm. The bracket is made of 304 stainless steel material.
2. The saltwater freezing tunnel consists of saltwater tanks, heat exchangers, circulating mixing devices, saltwater lifting devices, product conveying devices, saltwater distribution devices, and insulation covers. The tanks, heat exchangers, conveying parts, and water distributors in contact with saltwater are all made of 316 stainless steel. Belt width 1800mm, saltwater temperature -18 ℃. Low temperature saltwater can be sprayed onto the product through a pump, and the product can be frozen to -12 to -14 ℃ in 7-10 minutes. The evaporation temperature of the refrigeration system is -25 ℃.
3. The transition conveyor belt separates the saltwater portion from the rear equipment to prevent saltwater from entering the tunnel. The conveyor belt is made of PE material, with a width of 1800mm, and the bracket is made of stainless steel 304.
4. The secondary freezing tunnel freezer consists of a heat exchanger, a circulating fan, a product conveying device, and an insulation shell. The conveyor belt has a width of 1800mm and is made of 304 stainless steel mesh belt; 2-4-6-8 fans, the cold air temperature inside the chassis is -35 ℃, reducing the product temperature from -12 ℃ to -18 ℃. The evaporation temperature of the refrigeration system is -42 ℃.
5. The output descent conveyor is made of PE material, with a conveyor belt width of 1800mm and a bracket made of stainless steel 304 material.
6. There is also a saltwater tank and mixer, as well as a pump for transporting saltwater, which can be placed near the main equipment mentioned above, or in adjacent rooms or other locations to supply saltwater to the saltwater tank. The water tank capacity is 500-1000 liters. The main shaft and impeller of the mixer are made of stainless steel 316L. Frozen products are packaged in plastic frames (such as 600x400x200) and can be frozen through tunnels. Under normal circumstances, the weight inside the box is usually 10kg, and the load can be adjusted as needed. After freezing, a slight vibration can be used to remove the frozen product from the frame in a separate form.
characteristic
The width of the mesh belt is 1800mm, and it adopts a mesh belt form with high load-bearing capacity.
The salt water quick freezing machine adopts an immersion type 316 stainless steel plate heat exchanger with high heat transfer efficiency.
Salt water concentration display and control system.
The belt operation adopts frequency conversion control, and the speed is continuously adjustable.
Efficient saltwater circulation and transportation system.
The height of the channel is 300mm.
