More than 60% of these tires in Ontario are currently being landfilled. Burying whole tires, however, is not a good disposal option because tires are resistant to compaction and take up a disproportionate amount of space. In some landfills, methane gas, given off by decaying wastes, collects in the cavities of tires, which causes them to float to the surface, becoming a potential breeding ground for mosquitoes and rats.
Roughly 10% of scrap tires are stockpiled in anticipation of finding a market for them in the future. The problem is, markets for tires and the demand for products made from recycled rubber have been slow to develop.
Technological developments over the past few decades have resulted in higher quality tires that meet tougher safety and performance standards, and have longer life spans. This addresses the first of the three Rs - Reduction. The major drawback, however, is scrap tires are now much more difficult to recycle because of their complex chemistry. Tires today are manufactured from natural and synthetic rubbers, elastomers, and fine powders called carbon blacks in variable mixtures. As a result, current technology has not been successful at reclaiming rubber from scrap tires close enough to its original form so it can be used again in the production of new tires. Experts say it's like trying to recycle a cake back into its original ingredients.
In 1989, the Ontario government introduced a $5 tire tax (plus 8% sales tax) on the purchase of every new tire in the province. Only tires for bicycles, farm machinery and garden tractors were exempt. The money raised from the tax was to be spent financing tire recycling projects, cleaning up stockpiles and creating markets for recycled tires. Instead, four years later, the tire tax succumbed to public ridicule and was killed after raising $120 million, of which only $12 million was allocated to the scrap tire industry. (Source: Canadian Press). The rest of the money disappeared into the province's general revenues.
Since tires have no positive sale value the illegal dumping of tires is on the rise. Hundreds of tires are dumped on private properties overnight, leaving rural landowners and municipalities paying for the costly clean-up. Currently in Ontario, anyone with a truck can pick-up tires without a waste hauling permit because the Ontario government has deregulated tire hauling to encourage collection. Haulers therefore are not required to report their drop-off destination. Consequently, a number of individuals are offering businesses a below market price for pick-up, and instead of taking the tires to a recycling company and paying a fee to leave them there, they just find a location to dump them late at night.
Reduction & Reuse
Twenty years ago, technological advances resulted in the introduction of the steel-belted radial tire that extended the service life of tires threefold. In fact, during the period 1979-1989, the number of cars on the road in Canada increased approximately 20 percent, yet replacement tire sales in 1989 were approximately 12 percent lower than 10 years previously. (Source: The Rubber Association of Canada).
The resale of reusable tires also contributes to reduction. When replacement tires are purchased, tire dealers take back used tires from consumers, a proportion of which are still in good condition and can be resold back to the public. David Morgan of the Rubber Association of Canada estimates that 5-10% of Ontario's used tires are re-sold.
The best use for a worn tire is to have it retreaded. This diverts an estimated 10-15% of tires from the waste stream. Every time a passenger tire is retreaded over 4 gallons of oil is saved from producing a new tire, and the savings on a truck tire can be as much as 15 gallons per tire. (Source: The Tire Retread Information Bureau).
Retreaded tires must meet strict performance and safety standards and just like new tires they will last a long time with proper maintenance. The retreading of passenger tires, however, has severely declined over the last 15 years mainly because the cost of buying new tires is comparable to quality retreads, and the public's perception of retreads is that they are of poorer quality and of questionable reliability. In contrast, retreaded truck tire sales have increased due to a larger price differential between new and retreaded truck tires and customer satisfaction in overall performance.
Other uses for whole scrap tires include landscape borders, playground equipment, dock bumpers, highway crash barriers, artificial reefs and breakwaters.
To prolong the service life of your tires check them regularly for proper inflation pressure, rotation, correct balance and wheel alignment. Avoid making sudden starts and turns which wear tires out more quickly, and anticipate stops. Don't drive into curbs. Driving less i.e. taking alternative forms of transportation also helps extend the life of your tires.
Recycling
Less than 5% of tires worldwide are now being recycled. (Source: The Rubber Association of Canada). Some manufacturers of scrap tire products shred whole tires into pieces or stamp parts out of tire side walls for assembly into new products such as door mats, handbags or floor coverings. The market potential for this type of low technology end-product remains relatively small, however, and it is not a viable solution to the scrap tire problem.
Other manufacturers use a combination of physical and chemical processes to produce granulated rubber, commonly known as crumb rubber. Whole tires are ground to a degree of fineness or they can be frozen and shattered. The rubber, steel and fibre is then separated out using screens, magnets and density techniques. (Source: National Rubber Company Inc.). Crumb rubber can be used as a substitute for virgin rubber in a variety of rubber-based products including: bonding tape, irrigation pipes, carpet underlay, footwear, recreational surfaces, waterproofing compounds for roofs and walls, and joint and crack sealants.
Today, however, the greatest demand for crumb rubber is to use it as an additive in asphalt cement for paving roads. For example, using a 3 per cent rubber mix, one kilometre (three-fifths of a mile) of rubberized highway could absorb as many as 7,500 scrap tires. While the United States Federal Highway Administration and the Environmental Protection Agency have approved the use of certain types of rubber asphalt cements over other formulas available on the market, Ontario is still studying the option in a number of demonstration projects. Some experts in the U.S., however, are arguing that the use of rubberized asphalt is premature mainly because the long-term performance of the product has not been adequately evaluated, nor have the environmental impacts that includes air emissions from the cement plants and the recyclability of the end-product.
National Rubber Company Inc. in Toronto is one of the largest independent manufacturers of recycled rubber products in North America. The company currently uses about 24,000 tonnes of various types of scrap rubber a year to produce a number of automotive, industrial and consumer products. In 1992 the Ontario Ministry of the Environment gave National Rubber an $8 million grant to build a new plant (National Rubber Recycling Inc.) to process their own crumb rubber. The plant began operating at the end of January '94, processing 350,000 tires in its first year. The company expects to process 1.5 million tires in its second year.
The three major crumb rubber producing plants in Ontario are National Rubber in Toronto, Recovery Technologies Inc. in Cambridge, and Thermofriction Waste Recycling Inc. in Agincourt.
Recovery
In 1984, the Ontario Ministry of the Environment produced a Blueprint for Waste Management in Ontario which advanced the concept of a "4Rs" approach to waste management: Reduce, Re-Use, Recycle, Recover. Ten years later the 4th R was widely dismissed as a unacceptable means of disposal because it was seen as a quick-fix solution and it's not "green" to destroy a resource that could otherwise be utilized. Furthermore, when costly cement kilns are built they require an ongoing supply of large volumes of tires to continue operating, and that will likely limit the availability of tires to the recycling industry, which should be supported first.
The scrap tire crisis, however, has lead to the burning of whole or shredded tires to recover energy, which can be used as an alternative or supplement to fossil fuels. David Morgan reports that scrap tires have about 10% more heat value by weight than coal and burns comparatively cleaner.
Tire-derived fuel (TDF) has proven to be a very good market for tires in Japan, the U.S., and Europe, and the demand is expected to grow. While some Canadian provinces have accepted using tires as a fuel for paper mills, industrial boilers and cement kilns, Ontario has banned incineration efforts. In the U.S. 9% of scrap tires are presently being burned for energy.
Environmentalists are concerned about the toxic emissions which are unavoidably going to end up in the environment when tires are incinerated. Pollution control devices are never 100% effective no matter how new and improved.
The most common emissions include volatile organic chemicals (VOCs) such as benzene, chloroform, 1,2-dichloroethane (DCE), methylene chloride (MC) and metals such as lead, mercury, chromium and zinc. All of these VOCs and the heavy metals are recognized carcinogens, capable of damaging the central nervous system and the liver. (Source: Citizen's Clearinghouse for Hazardous Wastes). Furthermore, during the combustion process, new chemical by-products are created which didn't exist in the original waste. These are called "Products of Incomplete Combustion" (PICs), and dioxins and furans are the most common PICs.
Experts have also warned that incinerators over time, like any machine, are likely to wear out and break down with constant use, which could have a negative impact on emission controls.
Contacts:
The Recycling Council of Ontario's e-mail address is: rco@rco.on.ca.