From 1998 to 2001, all three major markets for scrap tires have expanded, while the number of stockpiled tires has fallen, according to a soon-to-be-released scrap tire market study by the Rubber Manufacturers Association.
Not only have those three markets-tire-derived fuel (TDF), ground rubber and civil engineering applications-grown since 1998, but the RMA also found that 77.6 percent of all scrap tires generated in 2001were reused, recovered or recycled into an end product, said Michael Blumenthal, the RMA's senior technical adviser.
Last year the number of tires recycled into ground rubber surged 120 percent to 33 million tires, largely due to greater demand for 5/8-, 3/4- and 1/2-inch pieces used in playground surfaces, horse arena flooring, running tracks, soil amendments and horticultural applications, Mr. Blumenthal said. Tire usage in civil engineering applications doubled since 1998 to 40 million tires as tire shreds were used not only for road embankments but also in landfill construction projects.
In contrast, TDF usage grew slightly to 115 million tires, from 114 million tires. However, Mr. Blumenthal noted that the TDF sector still grew despite overcapacity and consolidation in the paper and pulp industries, which caused many mills to shut down. The Enron scandal further impacted the TDF market by causing utility companies to scale back on costs.
Cement kilns, which in 1998 were not a big end-user of TDF, helped compensate for the downturn in TDF demand in the paper and pulp industries.
``Where we've made up ground is in the cement industry, which, a couple of years ago, was a soft spot because of the strong economy and the fact that a lot of cement kilns are at full capacity,'' he explained. ``They weren't that interested in tires because they wanted to make it as convenient for themselves to make cement as possible. Now a lot of kilns are looking to save money and increase efficiency. Once again, tires became a component of that management theme.''
Use of tire shreds is less costly to cement kilns than coal, Mr. Blumenthal added, and tire shreds help increase production capacity because of the amount of heat generated in the kiln.
Based on its survey of state agencies, the RMA estimates that the national stockpile of scrap tires totaled 306 million-unchanged from 1998's total, but a dramatic decline from 1 billion in 1990.
Mr. Blumenthal emphasized that states had cleaned up millions of tires in the three-year period, but the factor that caused the estimate to remain the same is that two states-Colorado and Connecticut-each have begun to count existing storage sites as abandoned.
It has become apparent, he added, that 85 percent of stockpiled tires are concentrated in nine states: Texas, New York, Michigan, Alabama, Ohio, Colorado, Connecticut, Pennsylvania and West Virginia.
Mr. Blumenthal wouldn't predict when the U.S. will reach a point of 100 percent recycling and reuse of scrap tires generated, but he said the RMA will continue to work with state governments to help achieve that goal.
``I think we're in a good position now,'' he said. ``We have created a lot of new information and training courses that the RMA has..., which we're taking into the field. We're working with all kinds of federal and state agencies on these training courses.''
Mr. Blumenthal predicted ``an era of more private/public partnerships,'' with the RMA partnering with Environmental Protection Agency regional offices and a growing number of state agencies.