Patent ID: 7662211

Claim:
A granular-material dehumidification plant including at least one silo or hopper arranged to receive granular material to be dehumidified at the top thereof and provided with a controlled lower delivering mouth, at least one feeding duct designed to be dipped in the granular material contained in each hopper to supply hot and dry processing air thereto, and at least one exhaust duct for humid processing air; at least two molecular sieve towers arranged alternately to supply hot and dry processing air to said at least one hopper, each tower delimiting therein a space for housing molecular sieves and a chamber for housing heating means, said space and said chamber being in fluid communication with one another at one end thereof, while being in fluid communication, at the other end thereof, with a respective air inlet/outlet duct; air pressurizing or pumping means arranged to receive, at the suction (inlet) side thereof, humid processing air from a respective exhaust duct, and to feed pressured air, at the delivery side thereof, to each molecular sieve tower; switching-shunting means located between the delivery of said pressurizing means and said inlet/outlet ducts of said housing spaces for molecular sieves thereby switching at least one of said molecular sieve towers between a processing step and a regeneration step; and a programmable electronic control unit, wherein it comprises pressurizing valve means located between said inlet/outlet ducts of said housing chamber of said heating means for each molecular sieve tower and arranged to ensure a minimum pressure within a tower during a regeneration step, and temperature detecting means electrically connected to an input of said programmable electronic control unit.