A Road of Opportunities

Discarded tires, long a liability to communities and the nation, are finally being recognized as a valuable asset and an eminently recyclable resource. Farsighted states and businesses are initiating efforts to reap the benefits of this new form of “black gold."

The majority of tires that are not recovered are not taken to landfills, but are dumped in tire piles, in vacant lots and ditches, or along railroad tracks and rural roads. In fact, a 1987 Waste Recovery Inc. (Dallas) estimate indicates that close to 200 million tires are improperly disposed of every year, which has led to the accumulation of approximately 2 billion discarded tires during the past 10 years.

The improper disposal of tires creates a breeding ground for encephalitis-carrying mosquitoes and other vermin, posing serious public health problems. Tire piles are also fire hazards. Ignited tire piles are extremely difficult to extinguish, as evidenced by blazes in New England, Virginia, New Jersey, and Ontario that burned for days.

Scrap Tire Markets

On the positive side, tires can be valuable resources. Scrap tires can be used in a variety of applications, from marine docking fenders and shoreline erosion control aids to road asphalt and new rubber products.

Depolymerized rubber or reclaimed rubber from scrap tires can be used in the manufacture of new tires and tubes. In fact, employing scrap instead of virgin natural or synthetic rubber saves money, and, reportedly, the structural change of the compound containing depolymerized rubber caused by recycling produces a superior tire. However, the use of reclaimed rubber as depolymerized rubber in tire manufacture has significantly decreased in recent years due to the change in tire technology to radial tires. Reclaimed rubber is also used in the manufacture of molded rubber goods and brake material.

According to ADL, there's capacity for processing approximately 120 million pounds of crumb rubber per year, but current demand is only about 80 million pounds annually. The most promising application for crumb rubber is in rubber-modified asphalt, which includes between 1- and 4-percent crumb rubber content. This use has been investigated in Connecticut, Florida, Massachusetts, Nebraska, New Hampshire, New Jersey, New York, Ohio, and Washington. Tire chips can also used as a substitute for stone and gravel as lightweight fill in road construction or as a light aggregate material on road surfaces. Minnesota and Wisconsin are evaluating these applications.

In the 1970s, up to 1 million whole tires were used annually to form artificial reefs. However, present demand for whole scrap tires is running between 100,000 and 200,000 tires annually. Split tires have long been reused in such items as woven rubber floor mats, fences, dock bumpers, and sandals, and are consumed in quantities of about 2 million to 3 million annually.

The largest application for old tires, of course, is retreading, a process in which the outer layers of the tires are buffed and a new tread is applied to the used tire casing with a combination of glue and heat treatment. Truck tires can be retreaded two or three times, provided there is sidewall integrity. Used passenger car tires tend to be discarded, even if the casings are suitable for retreading, for several reasons: inexpensive imported tires are available at about the same price as retreaded tires, consumers tend to be concerned about the safety and durability of retreaded tires, and there has been an increase in the manufacture of radial tires, which are subject to belt separation during retreading. ADL estimates that 13 percent of domestic passenger car tires were retreaded in 1986 compared with 39 percent of truck tires.

Recovering Energy

Tires are a heterogeneous mixture of vulcanized or cross-linked polymers, carbon black, dispersing oil, sulfur, synthetic fibers, pigments, processing chemicals, and steel or fiberglass. Because the bulk of these tire materials is derived from petroleum, shredded or chipped tires, with their steel belts removed, have an energy value of approximately 15,000 British thermal units (Btu) per pound.

Therefore, tire chips have been developed as a fuel source, tire-derived fuel (TDF), which has found its greatest use in cement kilns as a 10-percent mixture with coal. The use of TDF in pulp and paper mills, which use large amounts of wood waste as fuel, also has been well demonstrated. Another market for TDF is use as a partial fuel substitute in industrial boilers. Rubber can be burned compatibly with other solid fuels and has a Btu value and sulfur concentration approximately equal to coal.

Tire pyrolysis, a heat process for producing oil and carbon black from scrap tires, has not proved to be economically viable. Even when oil has hit $40 a barrel, there has been no market for the oil and carbon black obtained.

New Market Developments

A number of new uses for old tires are presently in the research and development stage or early stages of marketing and implementation:

Composting facilities have been using tire chips to replace wood chips in sewage sludge processing.

Experiments are now under way by Tire Technologies Inc. (Grosse Pointe, Mich.) to ascertain the effectiveness of using tire chips as landscaping mulch and as an absorbent for oils, hazardous sludge, and chemical wastes.

There has been some success in combining scrap tire rubber with scrap plastics to manufacture buckets and hoses.

Tire mats are being used to curb erosion at construction sites.

Reidel-Omni Rubber Products (Portland, Ore.) has announced plans to manufacture rubber railroad crossings from scrap tires. The company anticipates using 16 million pounds of used tires in the next four years, the equivalent of 400,000 scrap passenger car tires.

Tollbridge Reduction System (Colbourne, Ontario) has developed a novel approach to scrap tire processing. The Tollbridge system will bombard a whole scrap tire with microwaves, thereby reducing a 20-pound passenger car tire to its basic components--9 pounds of carbon, 2 pounds of steel, 0.2 pound of sulfur, and 1 gallon of oil. Each of these components can be marketed separately.

Public Policy Intervention

State government action targeting the recovery and proper disposal of scrap tires has significantly increased in the last two years. In 1989, 13 states passed scrap tire legislation or regulations. Thus far in 1990, 10 additional states (Arizona, Indiana, Kansas, Kentucky, Michigan, Missouri, Nebraska, New York, Utah, and Vermont) have adopted new scrap tire laws or amendments, bringing the total number of states with tire laws or regulations to 34. Most of these laws impose scrap tire fees that are used for scrap tire management and recycling programs.

At the federal level, Rep. Esteban Torres (D-Calif.) introduced the Tire Recycling Incentives Act (HR 4147) in March. At about the same time, Sens. Tim Wirth (D-Colo.) and John Heinz (R-Pa.) introduced a companion piece of legislation, S 2462, in the Senate.

Both of these tire bills would establish a national tire credit system, a major market development incentive. Under this system, scrap tire processors would be entitled to receive variable credit for each tire processed. New tire manufacturers, in turn, would be required to purchase a certain number of credits from scrap tire processors. For the first year, manufacturers would be required to buy credits equaling 30 percent of their annual production; over the following 10 years, the level of credits would increase 5 percent annually, so that by 2001 manufacturers would be required to purchase credits equaling 80 percent of their production.

This Torres-Wirth-Heinz legislation is likely to be added to legislation to reauthorize the Resource Conservation and Recovery Act, which likely will be addressed by Congress in 1991.

Two other federal scrap tire proposals--HR 4321, sponsored by Rep. George Hochbrueckner (D-N.Y.), and S 2477, sponsored by Sen. Claiborne Pell (D-R.I.)-seek to require the Department of Commerce to undertake a study of scrap tire disposal and markets.

Processing Opportunities and Equipment

With this market and legislation information as a backdrop, it's evident that intermediate processing opportunities exist for tire splitting, shredding, chipping, and crumbing operations. Tire Recycling Inc. (Saugerties, N.Y.) is one company that plans to take advantage of this.

In 1990, says Bill Reinhardt, the company's vice president, Tire Recycling will shred and split 1 million scrap tires for proper landfill disposal. In addition, the company plans to expand in 1991 with the purchase of granulators and has located new secondary material markets for its products, which include 3/8-inch TDF chips and crumb rubber for matting and athletic tracks, Reinhardt says.

He forecasts processing 1.3 million tires in 1991 with the following breakdown: 35 percent splitting and shredding for landfilling; 40 percent for TDF; and 25 percent for crumb rubber/recycled products.

For new entrants into the scrap tire processing business, there is a variety of scrap tire processing equipment available to meet end-market requirements. Cutters, slicers, and balers can be used to reduce the volume of tires for storage and landfill purposes. Shredders and choppers reduce tires to fist-sized and smaller particles, preparing them to be burned as TDF. Cracker mills and granulators further reduce tire particle size for rubber reclamation or use in asphalt. Incinerators bum whole or partial tires to produce heat and steam for generating power. Pyrolite systems use heat to break down tires into their components (oil, flammable gases, carbon black, and steel) for reuse.

Cryogenic processes use liquid nitrogen at -320 degrees F to make tires brittler prior to size reduction, which allows them to be ground more easily.

Market Development Initiatives

In an effort to develop new scrap tire recycling markets and to expand existing ones, the Rubber Manufacturers Association recently formed the Scrap Tire Management Council (see sidebar at left). Other market development initiatives have been undertaken by states that are providing funds to the private sector to develop markets for scrap tire rubber.

According to Mary B. Sikora, publisher of Scrap Tire News, a bimonthly newsletter devoted to scrap tire recovery, as of last spring, 10 states had programs established to encourage market development activities for scrap tire recovery. Another eight states had proposals under consideration in their legislatures.

These state tire recovery programs are funded through a tax or fee on tire sales or vehicle registrations, with the exception of Maryland, which uses a state budget appropriation. Tire recycling funds are then established, with a substantial portion earmarked for direct, low-interest loans; research and development grants; and/or scrap rubber subsidies to the private sector.

The use of loans and grants may play a great role in developing new tire recycling business ventures. Private capital markets are usually much less responsive to early stage business development.

Of course, the key to investment in scrap tire recovery, like any other material recycling proposal, lies in the viability of long-term end markets. The use of such market development tools can provide a focused approach to scrap tire management efforts.

[SIDEBAR]

Minnesota Develops Scrap Tire Opportunities

State recycling market development efforts across the country have targeted scrap tires for increased recycling.

An example of such efforts has been undertaken by the Minnesota Pollution Control Agency (MPCA), which has operated a scrap tire loan program since 1985. The program is designed to help the private sector meet the state’s substantial scrap tire processing needs. Up to $1.5 million (or a maximum of 90 percent of eligible capital costs) may be loaned for fixed asset (land, building, and equipment) acquisition at a fixed annual interest rate as low as 3 percent. Shredding operations, product manufacture, and road construction are among eligible projects. The MPCA has made loans totaling nearly $750,000 to two businesses involved in crumb rubber recycling manufacturing.

The MPCA also offers grants up to $30,000 for businesses to conduct feasibility studies to develop alternative disposal methods for scrap tires. For example, it has funded a $30,000 research and development study undertaken by Twin Cities Testing (St. Paul, Minn.) to determine the effects of using tire chips as a substitute material in road building in areas where subsurface soil will not support conventional road building material.

There is $1 million allocated this year to clean up tire dumps in Minnesota, according to Frank Wallner, the MPCA’s project manager. Information on bidding can be obtained by calling 612/296-6300.

[SIDEBAR]

Scrap Tire Management Council Formed

The Washington, D.C.-based Rubber Manufacturers Association (RMA) has announced plans to form the Scrap Tire Management Council, which, according to Thomas E. Cole, RMA president, is “to assist in developing and promoting the use of scrap tires as a valuable resource in an environmentally and economically sound manner.”

The council’s goals include development of enough markets over the next five years to use more than 50 percent of the scrap tires generated annually in the United States, reducing significantly the number of scrap tires going to stockpiles and landfills. The council’s market development efforts will include matching suppliers, distributors, intermediate processors, and end-users in potentially high-volume uses, such as asphalt paving and as a fuel supplement in cement kilns and utility and industrial boilers. To help meet those goals, the council may establish an advisory group of collectors, processors, and end-users.

Plans also call for the council to establish a global data base, which will include information on new recycling and disposal technologies, scrap tire supplies, and specifications for scrap rubber products. Other planned council activities include providing technical assistance to federal, state, and local legislative bodies on establishing scrap tire regulatory or incentive programs.

Discarded tires, long a liability to communities and the nation, are finally being recognized as a valuable asset and an eminently recyclable resource. Farsighted states and businesses are initiating efforts to reap the benefits of this new form of “black gold."

The majority of tires that are not recovered are not taken to landfills, but are dumped in tire piles, in vacant lots and ditches, or along railroad tracks and rural roads. In fact, a 1987 Waste Recovery Inc. (Dallas) estimate indicates that close to 200 million tires are improperly disposed of every year, which has led to the accumulation of approximately 2 billion discarded tires during the past 10 years.

The improper disposal of tires creates a breeding ground for encephalitis-carrying mosquitoes and other vermin, posing serious public health problems. Tire piles are also fire hazards. Ignited tire piles are extremely difficult to extinguish, as evidenced by blazes in New England, Virginia, New Jersey, and Ontario that burned for days.

Scrap Tire Markets

On the positive side, tires can be valuable resources. Scrap tires can be used in a variety of applications, from marine docking fenders and shoreline erosion control aids to road asphalt and new rubber products.

Depolymerized rubber or reclaimed rubber from scrap tires can be used in the manufacture of new tires and tubes. In fact, employing scrap instead of virgin natural or synthetic rubber saves money, and, reportedly, the structural change of the compound containing depolymerized rubber caused by recycling produces a superior tire. However, the use of reclaimed rubber as depolymerized rubber in tire manufacture has significantly decreased in recent years due to the change in tire technology to radial tires. Reclaimed rubber is also used in the manufacture of molded rubber goods and brake material.

According to ADL, there's capacity for processing approximately 120 million pounds of crumb rubber per year, but current demand is only about 80 million pounds annually. The most promising application for crumb rubber is in rubber-modified asphalt, which includes between 1- and 4-percent crumb rubber content. This use has been investigated in Connecticut, Florida, Massachusetts, Nebraska, New Hampshire, New Jersey, New York, Ohio, and Washington. Tire chips can also used as a substitute for stone and gravel as lightweight fill in road construction or as a light aggregate material on road surfaces. Minnesota and Wisconsin are evaluating these applications.

In the 1970s, up to 1 million whole tires were used annually to form artificial reefs. However, present demand for whole scrap tires is running between 100,000 and 200,000 tires annually. Split tires have long been reused in such items as woven rubber floor mats, fences, dock bumpers, and sandals, and are consumed in quantities of about 2 million to 3 million annually.

The largest application for old tires, of course, is retreading, a process in which the outer layers of the tires are buffed and a new tread is applied to the used tire casing with a combination of glue and heat treatment. Truck tires can be retreaded two or three times, provided there is sidewall integrity. Used passenger car tires tend to be discarded, even if the casings are suitable for retreading, for several reasons: inexpensive imported tires are available at about the same price as retreaded tires, consumers tend to be concerned about the safety and durability of retreaded tires, and there has been an increase in the manufacture of radial tires, which are subject to belt separation during retreading. ADL estimates that 13 percent of domestic passenger car tires were retreaded in 1986 compared with 39 percent of truck tires.

Recovering Energy

Tires are a heterogeneous mixture of vulcanized or cross-linked polymers, carbon black, dispersing oil, sulfur, synthetic fibers, pigments, processing chemicals, and steel or fiberglass. Because the bulk of these tire materials is derived from petroleum, shredded or chipped tires, with their steel belts removed, have an energy value of approximately 15,000 British thermal units (Btu) per pound.

Therefore, tire chips have been developed as a fuel source, tire-derived fuel (TDF), which has found its greatest use in cement kilns as a 10-percent mixture with coal. The use of TDF in pulp and paper mills, which use large amounts of wood waste as fuel, also has been well demonstrated. Another market for TDF is use as a partial fuel substitute in industrial boilers. Rubber can be burned compatibly with other solid fuels and has a Btu value and sulfur concentration approximately equal to coal.

Tire pyrolysis, a heat process for producing oil and carbon black from scrap tires, has not proved to be economically viable. Even when oil has hit $40 a barrel, there has been no market for the oil and carbon black obtained.

New Market Developments

A number of new uses for old tires are presently in the research and development stage or early stages of marketing and implementation:

Composting facilities have been using tire chips to replace wood chips in sewage sludge processing.

Experiments are now under way by Tire Technologies Inc. (Grosse Pointe, Mich.) to ascertain the effectiveness of using tire chips as landscaping mulch and as an absorbent for oils, hazardous sludge, and chemical wastes.

There has been some success in combining scrap tire rubber with scrap plastics to manufacture buckets and hoses.

Tire mats are being used to curb erosion at construction sites.

Reidel-Omni Rubber Products (Portland, Ore.) has announced plans to manufacture rubber railroad crossings from scrap tires. The company anticipates using 16 million pounds of used tires in the next four years, the equivalent of 400,000 scrap passenger car tires.

Tollbridge Reduction System (Colbourne, Ontario) has developed a novel approach to scrap tire processing. The Tollbridge system will bombard a whole scrap tire with microwaves, thereby reducing a 20-pound passenger car tire to its basic components--9 pounds of carbon, 2 pounds of steel, 0.2 pound of sulfur, and 1 gallon of oil. Each of these components can be marketed separately.

Public Policy Intervention

State government action targeting the recovery and proper disposal of scrap tires has significantly increased in the last two years. In 1989, 13 states passed scrap tire legislation or regulations. Thus far in 1990, 10 additional states (Arizona, Indiana, Kansas, Kentucky, Michigan, Missouri, Nebraska, New York, Utah, and Vermont) have adopted new scrap tire laws or amendments, bringing the total number of states with tire laws or regulations to 34. Most of these laws impose scrap tire fees that are used for scrap tire management and recycling programs.

At the federal level, Rep. Esteban Torres (D-Calif.) introduced the Tire Recycling Incentives Act (HR 4147) in March. At about the same time, Sens. Tim Wirth (D-Colo.) and John Heinz (R-Pa.) introduced a companion piece of legislation, S 2462, in the Senate.

Both of these tire bills would establish a national tire credit system, a major market development incentive. Under this system, scrap tire processors would be entitled to receive variable credit for each tire processed. New tire manufacturers, in turn, would be required to purchase a certain number of credits from scrap tire processors. For the first year, manufacturers would be required to buy credits equaling 30 percent of their annual production; over the following 10 years, the level of credits would increase 5 percent annually, so that by 2001 manufacturers would be required to purchase credits equaling 80 percent of their production.

This Torres-Wirth-Heinz legislation is likely to be added to legislation to reauthorize the Resource Conservation and Recovery Act, which likely will be addressed by Congress in 1991.

Two other federal scrap tire proposals--HR 4321, sponsored by Rep. George Hochbrueckner (D-N.Y.), and S 2477, sponsored by Sen. Claiborne Pell (D-R.I.)-seek to require the Department of Commerce to undertake a study of scrap tire disposal and markets.

Processing Opportunities and Equipment

With this market and legislation information as a backdrop, it's evident that intermediate processing opportunities exist for tire splitting, shredding, chipping, and crumbing operations. Tire Recycling Inc. (Saugerties, N.Y.) is one company that plans to take advantage of this.

In 1990, says Bill Reinhardt, the company's vice president, Tire Recycling will shred and split 1 million scrap tires for proper landfill disposal. In addition, the company plans to expand in 1991 with the purchase of granulators and has located new secondary material markets for its products, which include 3/8-inch TDF chips and crumb rubber for matting and athletic tracks, Reinhardt says.

He forecasts processing 1.3 million tires in 1991 with the following breakdown: 35 percent splitting and shredding for landfilling; 40 percent for TDF; and 25 percent for crumb rubber/recycled products.

For new entrants into the scrap tire processing business, there is a variety of scrap tire processing equipment available to meet end-market requirements. Cutters, slicers, and balers can be used to reduce the volume of tires for storage and landfill purposes. Shredders and choppers reduce tires to fist-sized and smaller particles, preparing them to be burned as TDF. Cracker mills and granulators further reduce tire particle size for rubber reclamation or use in asphalt. Incinerators bum whole or partial tires to produce heat and steam for generating power. Pyrolite systems use heat to break down tires into their components (oil, flammable gases, carbon black, and steel) for reuse.

Cryogenic processes use liquid nitrogen at -320 degrees F to make tires brittler prior to size reduction, which allows them to be ground more easily.

Market Development Initiatives

In an effort to develop new scrap tire recycling markets and to expand existing ones, the Rubber Manufacturers Association recently formed the Scrap Tire Management Council (see sidebar at left). Other market development initiatives have been undertaken by states that are providing funds to the private sector to develop markets for scrap tire rubber.

According to Mary B. Sikora, publisher of Scrap Tire News, a bimonthly newsletter devoted to scrap tire recovery, as of last spring, 10 states had programs established to encourage market development activities for scrap tire recovery. Another eight states had proposals under consideration in their legislatures.

These state tire recovery programs are funded through a tax or fee on tire sales or vehicle registrations, with the exception of Maryland, which uses a state budget appropriation. Tire recycling funds are then established, with a substantial portion earmarked for direct, low-interest loans; research and development grants; and/or scrap rubber subsidies to the private sector.

The use of loans and grants may play a great role in developing new tire recycling business ventures. Private capital markets are usually much less responsive to early stage business development.

Of course, the key to investment in scrap tire recovery, like any other material recycling proposal, lies in the viability of long-term end markets. The use of such market development tools can provide a focused approach to scrap tire management efforts.

[SIDEBAR]

Minnesota Develops Scrap Tire Opportunities

State recycling market development efforts across the country have targeted scrap tires for increased recycling.

An example of such efforts has been undertaken by the Minnesota Pollution Control Agency (MPCA), which has operated a scrap tire loan program since 1985. The program is designed to help the private sector meet the state’s substantial scrap tire processing needs. Up to $1.5 million (or a maximum of 90 percent of eligible capital costs) may be loaned for fixed asset (land, building, and equipment) acquisition at a fixed annual interest rate as low as 3 percent. Shredding operations, product manufacture, and road construction are among eligible projects. The MPCA has made loans totaling nearly $750,000 to two businesses involved in crumb rubber recycling manufacturing.

The MPCA also offers grants up to $30,000 for businesses to conduct feasibility studies to develop alternative disposal methods for scrap tires. For example, it has funded a $30,000 research and development study undertaken by Twin Cities Testing (St. Paul, Minn.) to determine the effects of using tire chips as a substitute material in road building in areas where subsurface soil will not support conventional road building material.

There is $1 million allocated this year to clean up tire dumps in Minnesota, according to Frank Wallner, the MPCA’s project manager. Information on bidding can be obtained by calling 612/296-6300.

[SIDEBAR]

Scrap Tire Management Council Formed

The Washington, D.C.-based Rubber Manufacturers Association (RMA) has announced plans to form the Scrap Tire Management Council, which, according to Thomas E. Cole, RMA president, is “to assist in developing and promoting the use of scrap tires as a valuable resource in an environmentally and economically sound manner.”

The council’s goals include development of enough markets over the next five years to use more than 50 percent of the scrap tires generated annually in the United States, reducing significantly the number of scrap tires going to stockpiles and landfills. The council’s market development efforts will include matching suppliers, distributors, intermediate processors, and end-users in potentially high-volume uses, such as asphalt paving and as a fuel supplement in cement kilns and utility and industrial boilers. To help meet those goals, the council may establish an advisory group of collectors, processors, and end-users.

Plans also call for the council to establish a global data base, which will include information on new recycling and disposal technologies, scrap tire supplies, and specifications for scrap rubber products. Other planned council activities include providing technical assistance to federal, state, and local legislative bodies on establishing scrap tire regulatory or incentive programs.