Reclaimed Rubber

Rubber salvaged from tires and other rubber products is used to make hard rubber goods, garden hose, floor mats, and a variety of other rubber goods. The used rubber is shredded and passed under a magnet that removes pieces of metal. The rubber is then processed by either of two methods:

The rubber is cooked in a caustic-soda solution in a pressure cooker, or digester, at 375° F. (191° C.) for 12 to 20 hours. This step destroys any fabric that might be in the rubber and softens the rubber itself. Next, the rubber is washed, dried, and screened to remove foreign substances. It is then passed through a series of rollers that reduce it to a paper-thin sheet. Finally, the rubber is formed into a roll and sliced preparatory to milling.

is used to salvage rubber that does not contain fabric. The rubber is ground, mixed with oils and caustic soda, and then placed in pans that are heated with steam. Further processing, beginning with washing and drying, is as in the Mark process.