Abstract: The present invention relates to a particle separator device which comprises a centrifugal separator with a loading duct, a duct for discharging the agglomerated particles and a duct for the discharge of the gaseous flow. The device comprises Venturi-meter throttling means, a pressure element which has a pressure containment chamber which is preferably formed with a diaphragm which supports a movable part. A pneumatic connection is provided between the chamber and the throttling means, and a mechanical coupling is provided between the movable part and valve means for adjusting the width of the passage of the gaseous flow. The device is capable of self-adjusting according to the amount of granular material which is kept in suspension. The invention furthermore relates to an apparatus for the pneumatic conveyance of granular materials which uses the device described above.