SYSTEM FOR IMPROVING THE BALANCING OF COLD GASES IN A QUICK-FREEZING TUNNEL USING BUFFER ZONES AND EXTERNAL AIR-BLOWER CEILINGS

摘要

The invention relates to a method and unit for the cryogenic quick-freezing or cooling of products, in which the products to undergo cooling or quick-freezing travel through a cryogenic tunnel of the type in which a cryogenic fluid is injected indirectly into exchangers (batteries) that are located in the internal space of the tunnel and distributed along the product route in the tunnel. The tunnel is provided with means for injecting a cryogenic fluid, as well as a first buffer zone (ZT) located between the tunnel loading zone (ZC) and the first battery encountered by the products, and a second buffer zone located between the last battery encountered by the products and the tunnel outlet. The system is characterised in that the balancing of the cold gases inside the tunnel is improved by means of the following measures: the first buffer zone at least partially overlaps the loading zone; two air-blower ceilings (3) are provided outside the tunnel, placed against the inlet and outlet of the tunnel; and, if necessary, the air flow passing through one or each of the two air-blower ceilings is adjusted in order to re-balance the tunnel.