Recycling back to raw materials

USA Today (Society for the Advancement of Education), June, 1995

The Advanced Recycling Committee of the American Plastics Council (APC) is investigating and developing technologies to provide the industry with expanded options for commercializing new recycling methods. One such demonstration project involves a partnership between the APC and Conrad Industries, Inc., Centralia, Wash. The advanced recycling process converts plastics back into the raw materials from which they were made. This represents an exciting development in plastics recycling because it conserves natural resources, diverts materials from landfills, and produces marketable, useful products. The technology is similar to the processes used to recycle steel, aluminum, and glass.

Applying heat to plastics in the absence of oxygen produces liquid petroleum, carbon, and gas products. The process begins by feeding plastics into the system through an air lock to prevent air from entering the system. The plastics then move, via rotating paddles, through a tube heated to roughly 1,000[degrees]F.

Using these high temperatures in the absence of oxygen transforms the plastics into gas and small amounts of carbon that exit the tube. At this point, the carbon drops out of the system and is collected for sale. The majority of the gases are condensed into liquid product. Remaining gases are used within the system to generate heat for transforming plastics entering the tube.

The liquid product is shipped to refineries and plastics production facilities for use in manufacturing such items as synthetic fibers, new plastics, and other petroleum-based goods. It represents about 70-80% of the final output of the system. The carbon (five-10%) is sold for use in producing activated carbon, pigments, rubber goods, and applications in oil and agriculture.