Aggregate Classifier

Gravitational Inertial

The Buell Aggregate Classifiers combine gravitational, inertial, centrifugal and aerodynamic forces to efficiently classify materials at cutpoints ranging from 50 to 200 mesh (300 to 75 microns). The feed material and primary air enter the top of the unit and travel downward. The air makes a 120 degree change in direction. It then exits through the vanes, carrying fine particles with it. The coarse particles that are too heavy to make the turn fall to the bottom where they pass through the secondary air before they are discharged through a valve. Secondary air, entering below the vanes, passes through the curtain of falling particles. Those particles that are near cutpoint in size are diverted by the secondary air stream into an eddy current within the heart-shaped chamber. Some fines are captured as they enter the unit while others are drawn from the eddy. These are carried by the exiting air to a fabric filter for final recovery. The design of the Buell gravitational inertial classifier uses air flow, gravity and directional changes to achieve material cutpoints from 50 to 200 mesh.

View our Aggregate Classifier Video

• No moving parts within material flow stream
• Internal Lining - AR Plate or Ceramic
• Reduce loading or eliminate settling ponds
• Lower maintenance and operation costs (pumps, dredging, belt presses, flocculants)
• Reduce moisture and minimize asphalt costs
• Develop additional market opportunities for minus 200 mesh material

Centrifugal Classifiers

These Buell units employ centrifugal forces, similar to cyclones, to separate particles at cutpoints between 20 and 100 microns. A series of internal baffles apply drag forces to the coarse particles while allowing air to pass through them, resulting in separation of the fines. The heaviest particles drop to the bottom of the classifier where they are discharged through a valve. Prior to the discharge, secondary air is injected and passes through the material, and particles near the cutpoint are returned to the circulating chamber. The fine particles travel a spiral path into the outlets located on each side of the unit. The two air streams combine and enter a cyclone for final recovery of fine particles.

View our Centrifugal Classifier Video

• Internal Lining - AR Plate or Ceramic
• 75 tph feed rate for Transportable System
• Stationary systems up to 300 tph

Download a printable version of the Aggregate Classifier info. < PDF 419 KB >