Single Knife DE-STONER® Air Classifier

The GK Single Knife DE-STONER® Air Classifier is a fully proven design operating efficiently in various separating applications. This dry classifying system is capable of handling continuous, high volume production.

The completely dry system eliminates water handling and other “wet” system problems, yet can easily handle moist materials. The DE-STONER® Air Classifier combines vibration, fluidization with a high velocity / low pressure air stream to stratify material. Differences in terminal velocity of particles result in heavy items such as glass, metallics, and stones to be removed from lighter items such as paper, plastic and small wood.

The heart of your sorting system

1. Vibratory action moves material, with high density material settling to the bottom of the trough.
2. Fines drop out section (optional) removes smaller particle sizes like broken glass or dirt before reaching air fluidizer.
3. Air fluidizing section blows air through the material and creates turbulence to promote material stratification.
4. Material conveys over the air knife into the air stream. Heavier materials fall through the air stream to the discharge chute.
5. Marginal density material falls on the adjustable landing plate and drops back into discharge chute.
6. Light materials are carried beyond the landing plate and convey to the end of the DE-STONER®.
7. Ultra-light materials like thin film or paper are carried in the air stream to the product discharge zone.

Optional add-ons include GK’s

Fluff Knife Upgrade or DE-STONER® Drop-Out Boxes.

Successful separating and classifying applications include:

  • C&D materials
  • RDF fuel
  • Glass
  • Commingled materials
  • Shredded MSW
  • Shredded auto scrap fluff
  • Bio-mass fuel



  • The DE-STONER® Air Classifier uses air to separate heavy product from light product.
  • Environmental hazards associated with water separation is thus eliminated along with the inherent mess.
  • Easily adjustable to obtain varying degrees of separation.
  • Adaptable to a wide variety of products.
  • Separates material of different density, or of same density with different particle size.
  • Virtually jam-proof. No moving parts in contact with material flow.
  • Low energy demand with low HP motor and GK’s proven Two-Mass design.
  • Fully isolated design minimizes foundation requirements.
  • Heavy-duty, built to last construction.