Economics are bugaboo in scrap tire recycling

Abstract

IN MOST CITIES BURNING AS A MEANS OF TIRE DISPOSAL IS FORBIDDEN, AND MANY LANDFILLS NO LONGER ACCEPT TIRES. THE RECLAIMED-RUBBER INDUSTRY IS DECLINING IN COMPETITION WITH INEXPENSIVE VIRGIN SYNTHETIC RUBBERS. IN MOST CASES THE TECHNOLOGY FOR RECYCLING SCRAP TIRES HAS BEEN PROVED, BUT TYPICAL COSTS RANGE FROM $9 TO $20 PER TON. ON THE OTHER HAND, BOTH INDUSTRY AND RESEARCH INSTITUTIONS ARE OPTIMISTIC ABOUT THE SUCCESS OF THE RECYCLING PROCESS AND POTENTIAL APPLICATIONS. FOR EXAMPLE, THE FIRESTONE CO. HAS IDENTIFIED AS MANY AS 50 DIFFERENT CHEMICALS IN THE PRODUCTS DRIVEN OFF AND CONDENSED IN ITS AKRON PILOT PLANT, ALL THEM HAVING A PRACTICAL USE. THE RECOVERED OILS CAN BE USED TO MANUFACTURE RUBBER, PREPARE CARBON BLACK FOR RECYCLING, OR USE AS A PETROCHEMICALS FEEDSTOCK. RECOVERED GASES CAN FUEL THE RECOVERED REACTOR. WIRE CAN BE RECLAIMED FOR USE. CHAR CAN BE USED AS A PARTICULATE IN CONCRETE OR AS A FILTERING MEDIUM IN SEWAGE TREATMENT. IT IS GENERALLY THOUGHT THAT THE ECONOMICS OF THE PROCESS WILL STAND OR FALL ON CARBON BLACK. RESEARCH AGENCIES ARE INVESTIGATING THE USE OF RECYCLED TIRES AS A SOIL CONDITIONER, AN ABSORBER FOR CLEANING UP OIL SPILLS, AN ADDITIVE TO ASPHALT FOR ROAD PAVING, A MATERIAL FOR RUNNING TRACKS, ARTIFICIAL REEFS, AND BARRIERS AGAINST VEHICLE COLLISIONS WITH FIXED OBJECTS. THIS LAST APPLICATION IS BEING EXPLORED BY THE TEXAS TRANSPORTATION INSTITUTE UNDER A CONTRACT WITH NCHRP.