The screw de-stoner can be used in conjunction with all root crops. The integration of this system into a processing line dramatically reduces the potential for extreme wear and tear to associated equipment further along the installation. The screw de-stoner is constructed with a reception hopper with a vertical transport screw. The screw is driven by a reduction gearbox.

The circular water filled hopper receives the product to be de-stoned and in combination with the rotational action of the vertical screw auger draws the water and crop gently up the tube supported by the regular closed screw. The rotational action raises the product allowing the water to gravitate down the side of the auger. Heavy particles with negative buoyancy fall back into the base of the circular hopper where they can be collected for removal through an inspection door. Clean roduct (without stones) are transported out off the upper side of the transport screw. In the bottom there is a sieve which separates the stones and earth.

This machine is simple and effective, gives no damage to the product, is extremely durable, hard wearing and reliable  and easily to clean.

The capacity of the machine depends on the size of the product, and can be up to 8 tons/hour.