The links below answer questions and provide information on how we can reuse and recycle waste tires.
Can we reuse or recycle old tires?
Yes. Four alternative management methods may be utilized for disposing of waste tires: Reuse, Recycling, Pyrolysis, or Energy Recovery. Energy Recovery is discussed separately.
Reuse is the practice of giving a second life to a product, either using it again for the same purpose or using it for a different purpose. Reuse practices are different than recycling because no further processing is required.
Examples of tire reuse:
- Baling whole tires for use in bridge or roadbed construction;
- Using on docks or pilings as boat bumpers;
- Retreading tires for resale; and,
- Constructing lightweight tire-filled concrete blocks for retaining walls (or similar use).
The examples given above involve whole tires. In general, reuse practices do not involve significant processing, as is required in the recycling of materials. Not all proposed methods of reuse are lawful in Montana. For example, tires may not be used for riprap because this would violate Montana's Water Quality Act.
Recycling is the practice of processing waste products back into raw materials and then manufacturing the materials into a new product. The recycling of tires generally involves cutting the tires into smaller pieces, including grinding to create ground rubber.
Examples of tire recycling:
- Using crumb rubber to form new products such as rubberized asphalt, mats, and playground surfaces.
- Cutting, stamping or punching new products out of scrap tire rubber.
- Tire chips are used as daily landfill cover, fill in sewage drainage fields, and civil engineering projects, and as fuel.
For more information on markets and uses for waste tires, visit the EPA website on tires.
Waste tires and the Montana Motor Vehicle Recycling Act
Tires are considered to be "component parts" of a motor vehicle. Tire piles must be shielded from public view. This is why tires cannot be used as fences or building exteriors. If tires are used in alternative building construction, they must be covered with another material, such as stucco.
Does tire recycling occur in Montana? Yes, some tire recycling does occur in Montana, yet the majority of waste tires are landfilled. At this point, Montana has one resource recovery facility dealing exclusively with tires. That business operates a monofill for tires; offers tire chips for sewage drain fields, backfill material, and other products; and actively pursues other recycling opportunities. Another business makes livestock feeders from waste tires. Several businesses retread truck tires only; there is not a business retreading passenger tires in the state. For a list of these businesses and others that offer recycled products, see the Montana Guide for Buying Recycled Products.
There are no reporting requirements for recycling activities in the state and therefore other businesses could exist, but DEQ is not aware of them. Any business that stores tires, however, must comply with state laws and rules regarding their storage.
Pyrolysis is a process that uses thermal degradation in an oxygen-free environment to decompose the tire rubber into three recoverable materials: carbon black, oil, and gas. It is also known as gasification or liquifaction. The gas produced is normally then used to provide the energy to drive the pyrolysis. The oil can be used as a low-grade fuel oil. Tire manufacturers generally use a large percentage of carbon black in new tires, but pyrolysis produces a low quality carbon black that does not meet most manufacturers' expectations. There are no pyrolysis processors in Montana.
Could more recycling occur? Yes, if more recycling businesses operated in geographically diverse locations within Montana, thereby reducing costs associated with transporting waste tires to markets. But would enough waste tires be generated in that geographic location to keep the business solvent?
Challenges to Waste Tire Industries in Montana
Waste tire businesses in Montana face challenges to their success that reflect many of the reasons why recycling is hard to accomplish in Montana. Some of the factors that negatively affect the growth of waste tire industries in Montana are:
- Long transportation distances
- Low population densities
- Lack of in-state markets
- Unreliable supply conditions (due to less costly disposal options, such as landfills)
- High start-up capital investment costs
These same challenges often inhibit the growth and success of recycling programs and businesses across the state for many recyclable materials, including glass and plastic.
Why aren't tires recycled into new tires? Manufacturing tires involves vulcanization, a chemical process that treats rubber with sulfur to make the rubber stronger, more elastic and resistant to temperature changes. Vulcanization is also an irreversible process that prevents the true recycling of tires because the rubber cannot be melted down into virgin material again for reuse in a new tire.
Even separating tires into their basic components is a difficult and expensive process that yields materials with little value. A very small percentage of powdered scrap tire rubber has been used successfully as filler in the manufacture of new tires. Research continues to be done to increase the percentage of scrap that can be used without jeopardizing the integrity of the tire. (See the Rubber Manufacturers Association's online publication for more information about waste tire recycling markets.)