Patent ID: 7472494

Claim:
A dehumidification plant for granular material which comprises a compressed air source, control means for controlling the flow rate of compressed air applied by said source, at least one heating chamber of compressed air which is in fluid communication with said flow rate control means, at least one container of granular material to be dehumidified, diffuser means disposed in said container for dispersing compressed and hot air through said granular material in said at least one container, temperature sensor means arranged to detect the temperature of air leaving said at least one container, at least one programmable control unit, at least one compressed-air dehumidifying group located downstream of said flow rate control means, and at least one flow rate adjusting group for the dehumidified air coming from said at least one dehumidifying group located upstream of said at least one heating chamber each dehumidification group comprising: at least one pair of molecular sieve cartridge units, a valve distributing means having an inlet in communication with said compressed-air flow control means, and two outlets in fluid communication with said at least one pair of sieve cartridge units and an outlet in communication with the atmosphere, and a pair of unidirectional flow, regulator units for at least one pair of said sieve cartridge units is provided which are in fluid communication with one another through a connection duct, each unidirectional flow regulator unit being located downstream of at least one molecular sieve cartridge unit, each flow regulator unit comprising respective check valves and respective flow regulator means connected in parallel with said check valve; wherein each check valve is arranged to allow air to controllably flow from a molecular sieve cartridge unit while operating as an adsorbing unit to said connection duct, whereas air flow from one sieve cartridge unit to the other can occur through said flow regulator means thereby causing an air flow pressure drop.