Patent ID: 6944969

Claim:
A method for drying a mass of wet fibrous material, and in particular a mass of laundry, located in a drying zone; the method comprising the step: of ventilating, via a ventilation circuit, through the mass of fibrous material located in the drying zone, very moist air, whose moisture content is less than that inside the drying zone, at a pressure close to atmospheric pressure and at a temperature higher than that of the material to be dried; whereby it is then possible to extract from the fibrous material, by evaporation, in the form of water vapor, the moisture that it contains; the method additionally comprising the steps: of recovering the heat of condensation of the water vapor extracted from the fibrous material to heat the moist air, of providing leaks between the outside ambient air and said ventilation circuit upstream and downstream of the drying zone; wherein, the leaks are located on the part of the ventilation circuit upstream of the drying zone for exchanging a mass and heat to the outside ambient air; and the leaks are located on the part of the ventilation circuit downstream of the drying zone for exchanging a mass and heat by inlet of ambient air; whereby a balance of heat and mass is achieved without expelling large amounts of moist air into the ambient air; and whereby it is then possible to introduce natural leaks at least in part, and in particular in parts of the system that are mobile, in the normal operating cycle of the drying method.