Step 3: Rinsing and fractioning

This is the final phase of the course, in which the rubber granulate is split up in the requested sizes and cleaned to remove the last remains of steel, textile, stones and sand. This is an extensive process, in which the use of different high technology separation techniques is spread through several steps of the production.

All processes of the production of granulate are mechanically based. Neither nitrogen nor other utility materials are used.

Powder production

Depending on the requirements, granulates can be further processed into rubber powder of varying degrees of fineness. For that purpose special mills are used, in which the material is accelerated up to supersonic speed until crushed into powder. The powder may either be produced totally mechanically (ambient), or by addition of liquid nitrogen (cryogene), or by a combination of both these methods.

Mechanically ground powder has a big and irregular surface structure, which makes it suitable for combination with rubber compounds. Cryogen ground powder has a smooth and uniform surface structure, which for instance makes it suitable for use in paint or other products, which pass through nozzles when used.