IMPINGEMENT FREEZER

摘要

A tunnel freezing system employs multiple high velocity refrigerated air impingement jets (74) to quick freeze food products such as hamburger patties and fish or chicken filets. Ultra high molecular weight polyethylene blocks (92) are provided with a multiplicity of internal jet nozzles (98). These blocks are located in air ducts (70, 72) located above and below a conveyor belt (13, 15) so that the topsides and bottomsides of food products are impinged with the high velocity jets of refrigerated air so as to break up the boundary layer around the products to effect a much higher rate of heat transfer. A dual conveyor line (12, 14) employs direct drive centrifugal fans (46) to deliver high pressure refrigerated air to the air ducts. The air ducts are spaced apart so that return air can freely return to be re-refrigerated after impinging on the food products.