Abstract: A system and method for drying particulate material in a dual flow hopper employs multiple flow paths by which heated gas is inserted into the hopper at different levels. Gas is extracted from the hopper and is divided for flow along two flow paths, one of the flow paths receiving gas that has been dried and the other flow path receiving gas that has not been dried.

Abstract: An apparatus and method for control of moisture content of material such as thermoplastic pellets (80) in a hopper (30) is controlled by supplying dehumidified air from a dessicant bed (90) to the hopper (30) and returning air from the hopper (30) to the dessicant bed (90). A dew point sensor (10) in the return air path determines the moisture content of the material (80) in the hopper (30), and when the dew point drops to a pre-set level, a diverter (134) causes the return air flow to bypass the dessicant bed (90) and to be re-supplied to the hopper (30) without dehumidification. Two dessicant beds are provided, one of which is on-process while the dessicant in the other is regenerated.

Abstract: Moisture content of material such as thermoplastic pellets (80) in a hopper (30) is controlled by supplying dehumidified air from a dessicant bed (90) to the hopper (30) and returning air from the hopper (30) to the dessicant bed (90). A dew point sensor (10) in the return air path determines the moisture content of the material (80) in the hopper (30), and when the dew point drops to a pre-set level, a diverter (134) causes the return air flow to bypass the dessicant bed (90) and to be re-supplied to the hopper (30) without dehumidification. Two dessicant beds are provided, one of which is on-process while the dessicant in the other is regenerated.