Fractionation

JSC "Devulco" has developed the process for producing fine particles of devulcanized rubber reclaim, which is unique and unparalleled in the world. Devulco RRP™ combines the benefits of effectively devulcanized reclaim with the availability of necessary granulometric characteristics. The finest fraction of Devulco RRP™ may be 40 Mesh, i.e. 0.45 mm and smaller. This is a completely new type of product in the rubber industry, as most refiners produce the rubber reclaim in a form of leaves or sheets that are layered on top of each other and subsequently compressed into bales, coils, cylinders, blocks and other similar solid items. This might give the reclaim apparent similarity with the packaged virgin rubber, which comes in bales or other similar form. Neither kind of virgin rubber, including natural, isoprene rubber, styrene-butadiene (SBR), and all others, can be supplied as a powder for two main reasons:

  1. it is very difficult to form fine particles of rubber due to excessive flexibility and self-healing character of the solid, unless cryogenic processes are employed;
  2. 2. even if virgin rubber is transformed into small particles, they can easily adhere to each other at room temperature (or higher), and become hard to separate again.

That is why considerable engineering resources are directed to the development of rubber mixing equipment for the purpose of efficient processing of large pieces of source rubber. Other rubber components such as Carbon Black, sulfur, ZnO, stearic acid, etc., are usually supplied in the powder form, and sometimes as liquids, for example, mineral oil plasticizers. Powders can be stirred, dispersed and processed together much easier, compared to the large pieces of rubber.