Patent ID: 6436343
Filing Date: 2002-08-20
Classification: A61L

Abstract:
A method for the cold sterilization of a tunnel-type oven for pharmaceutical purpose, provided with at least one input chamber (3), fit to receive a plurality of bottles to be sterilized from oven input opening (31); at least one hot sterilization chamber (4) for said bottles, subsequently arranged with respect to said input chamber (3) and in communication therewith; at least one cooling chamber (5), subsequently placed with respect to said hot sterilization chamber (4) and in communication therewith, fit to receive sterilized, cooling down bottles, and having at least one oven output opening (51); conveying means (6), for conveying said bottles from said input chamber (3), subsequently to said sterilization chamber (4) and said cooling chamber (5), said oven (1) having a plurality of input ducts (33, 43) for introducing external air into said oven (1), and at least one output duct (34) for draining said air to an external environment, said method consisting essentially of the following operating steps which are periodically carried out:emptying the tunnel-type oven of bottles; airtightly closing said oven input opening (31) and said at least one oven output opening (51) and said input ducts (33, 43) and said at least one output duct (34) to airtightly seal the tunnel type oven; opening forced input means (35, 45, 55), for introducing a mixture of air and a cold sterilization fluid at least into said cooling chamber (5); supplying a predefined amount of said mixture of sterilization fluid and air, until a predefined static pressure is attained within the airtightly sealed oven; opening at least one output duct (37) for said sterilization fluid; stopping the supply of said sterilization fluid, and supplying said oven (1) with humidity controlled air, until a percentage of said sterilization fluid inside said oven (1) falls to a predefined value; closing said forced input means (34, 45, 55) and said at least one output duct (37), and reopening said oven input opening (31) and said at least one oven output opening (51), to allow entry of bottles into the oven.