Drier-extractor for particulate material with closed vessel - using max. capacity of blower for drying

摘要

Drier/extractor comprises a closed vessel contg. a funnel-shaped perforated wall for receiving the material, and a pressurised hot air source inside the vessel beneath the perforated wall. A throttle device allows escape of pressurised air in the vessel, and a pipe transfers material by the Venturi effect. A valve is provided for establishing a periodic variation in pressure in the vessel between min. and max. to allow transfer of material. The hot air source comprises a blower with decreasing pressure-discharge characteristic, so that max. discharge corresponds to min. pressure to ensure proper drying of the material. Valve displacement may be controlled electrically, mechanically or pneumatically by a periodic signal generator.