Preserving products after exploitation using foam technology (PU)

The storage cellar is insulated with Polyurethane (PU) foam, lined with stainless steel to prevent scratching the fish, the cold is evenly distributed, and the fish quality is guaranteed. This technology is being applied in many offshore fishing fleets of Southern fishermen.

After being mixed by machine, PU foam (Polyurethane) is sprayed directly into the pre-designed storage mold on the fishing boat with a density of 50 - 55 kg/m3. When sprayed between the wall of the storage room and the hull, the solution mixture will expand to form a mass that adheres tightly to the wooden wall, sealing, insulating well and avoiding impacts from the outside of the hull, increasing the safety of the fishing boat during storms and big waves. At the same time, this solution mixture adheres tightly to the bulkhead and the inside of the hull, preventing water from seeping in and keeping it cool.

With high tightness, PU foam is waterproof, hardens and increases the life of the hull. The PU foam hatch wall is covered with stainless steel, the joints between the two stainless steel panels and the corners of the hatch will be filled with heat-resistant silicone glue to seal. The hatch door is installed with a standard cold storage door (1 mm thick stainless steel on the outside, reinforced frame and PU foam on the inside). To tightly connect with the hatch frame, the door is also fitted with a rubber gasket around it and a stainless steel door lock.

With the above structure, the cellar has a high degree of airtightness, does not escape heat, and prevents water and outside air from penetrating. The cellar is made of PU foam material and will have a lifespan of 12 - 15 years. After exploitation, the products are immediately transferred to the cellar, mixed with crushed stone in layers and the cellar lid is tightly closed.

Through the actual use of PU foam tanks in some offshore fishing fleets in the provinces of Binh Dinh, Phu Yen, Quang Ngai... the results are very positive and much better than the previous cold storage tanks. Such as saving 30% of the amount of ice lost, extending the storage time, increasing the quality of aquatic raw materials after exploitation... The storage time for normal storage tanks is a maximum of 12 - 15 days (after 15 days, the raw materials begin to decline in quality and spoil); As for PU foam tanks, after 15 days or more, the quality of the raw materials is still guaranteed to be good.

The quality of raw materials of PU foam tanks increases by 30% compared to conventional tanks (the rate of raw materials losing quality of PU foam tanks is about 5%, while conventional tanks are about 35% of total output). PU foam tanks through actual use have brought high economic efficiency to fishermen.

>> The investment cost for a PU foam storage cellar is 2 - 2.5 times higher than a traditional storage cellar. But in return, the usage time is 3 - 4 times longer than a normal cellar and the product selling price is also 20 - 30% higher than normal storage.

According to Vietnam Fisheries