scrap tire disposal and recycling options

Scrap Tire Disposal and Recycling Options

Presentation to the Border Environment Cooperation Commissionby the Houston Advanced Research Center

December 2003

Agenda• Scrap tire overview• Human health and environmental effects

– Scrap tire stockpiles– Open-air tire incineration– Controlled tire incineration

• U.S. regulatory framework• Mexican regulatory framework• The BECC certification criteria and tire disposal and

recycling projects

Scrap tire generation• In the United States, about 280 million scrap

tires are generated per year (one per person)• In Mexico, about 40 million scrap tires are

generated per year • Many more used tires are imported into

Mexico, both legally and illegally, contributing extensively to the scrap tire problem

I. Scrap tire overviewII. Human health and environmental

effects III. U.S. regulatory framework

IV. Mexican regulatory framework

V. BECC certification criteria

Stockpiled tires in Mexico’s border cities





México Estimated tires in piles

Mexicali 5,000,000

Ciudad Juárez 3,000,000

Matamoros 800,000

Reynosa 500,000

Nuevo Laredo 100,000

Piedras Negras 50,000

Ciudad Acuna 50,000





Millions of tires consumed

% of tires consumed

Tire-derived fuel 115 41%Other uses

Civil engineering 40 14%Ground rubber (incl.

rubber asphalt)33 12%

Export 15 5%Cut/punched 8 3%

Misc/agriculture 7 2%Total use 218 78%Total scrap tires generated annually 281

What happens to tires in the U.S.?





What happens to tires in Mexico?

% of tires consumedDisposed of in piles 91%Retreaded 5%Burned for fuel 2%





Tire-derived fuel

Fuel BTU/lbPine wood 9,100

Bituminous coal 11,000 – 14,000

Coke 14,000

Tire chips 14,000 – 15,000

Fuel oil 18,000 – 19,000





Tire-derived fuel (cont.)• Most developed market for scrap tires worldwide• Depending on the incinerator and primary fuel, tires can be

burned whole or shredded• Used as a supplemental fuel with solid fuels such as coal or

wood• Used predominantly by the cement industry, also by power

plants, pulp & paper mills, and steel mills• Emissions profile is similar to coal’s, but with more particulate

matter and zinc and less SO2

41% of scrap tires generated in the U.S. in 2001 were used as fuel





Civil engineering applications

• Structural backfill• Erosion control• Landfill liners and covers• Municipal sewage treatment• Septic system drainage fields





Civil engineering applications (cont.)• Leaching from the metal in the tire chips is a

concern• Formation of “hot spots” in tire shreds used in

fill projects is a concern• ASTM standards have been developed to

manage these concerns

14% of scrap tires generated in the U.S. in 2001 were used in civil engineering projects





Ground rubber applications• Rubber-modified asphalt• Playgrounds and athletic surfaces• Molded & bound products

– Livestock mats– Speed bumps– Railroad crossings– Roof shingles

• New tire manufacturing

12% of scrap tires generated in U.S. in 2001 were recycled into ground rubber





Ground rubber applications (cont.)Rubber-modified asphalt• Largest use of ground rubber—12 million tires/yr• Withstands hot and cold temperatures better than traditional

asphalt• Lower life-cycle costs

– AZ study found 40% lower life-cycle cost over 25 years

• Increased traffic safety due to increased skid resistance and decreased maintenance needs

• Decreased traffic noise by 4-6 decibels





Other uses for scrap tires• Retreading (for tire casings in good condition)• Pyrolysis

– 40% carbon black– 25% pyrolysis oil– 20% hydrocarbon gases– 15% steel

• Gasification– H2, CO, CH4 and CO2 (Hydrogen economy potential)– 2004 DOE demonstration project of mobile gasification-to-power unit

in El Paso/Juárez area





Financial viability

• Supply — # of locally available scrap tires• Location — Distance of tire stockpiles from the recycling

center, and distance from markets for the end product• Size of system — economies of scale• Labor — costs of transporting, handling, and processing the

tires• Condition — tires that have been in stockpiles may be too

dirty or degraded for some options• Fuel costs — for TDF, cost of competing fuels such as coal

and natural gas

Viability of any tire disposal or recycling project is highly dependent on several project-specific factors





Health effects• Tires provide habitat for vectors of human disease

– Mosquitoes• Yellow fever, dengue fever, malaria, encephalitis and the

West Nile virus – Rodents

• Rabies, hantavirus, lyme disease, and the plague

• Transport of tires spreads invasive species– Asian tiger mosquito (Aedes albopictus) – Yellow Fever mosquito (Aedes aegypti )





Scrap tire pile hazards: Contaminant leaching

Contaminants can leach (in absence of fire) to:• Surface water• Ground water• Soil

• Aluminum • Barium • Chromium • Iron• Lead• Manganese• Zinc

• Volatile organic compounds (VOCs)

• Semi-volatile organic compounds (SVOCs)

Contaminants of concern include:





Scrap tire pile hazards: Fire• Highly combustible

– Ignition by arson or lightning strikes• 20 major tire fires annually in the U.S.• Costly and lengthy firefighting efforts;

substantial clean up problems • Sources of environmental contamination

– Air– Surface water and ground water– Soils





Human health effects of open tire fires• Nearby residents • Emergency responders• Acute and chronic health effects

• Irritation to skin, eyes, and mucous membranes• Respiratory effects• Central nervous system depression• Cancer





Air emissions from open burning of tires• Pose acute and chronic threats to health of nearby residents

– 16 times more toxic than residential wood combustion – 16,000 times more toxic than coal-fired utility emissions

• Contain Criteria Pollutants: Carbon monoxide (CO), particulate matter (PM), nitrogen dioxide (NOx), and sulfur dioxide (SO2)

• Contain Hazardous Air Pollutants (HAPs): Benzene, dioxins/furans, hydrogen chloride, polynuclear aromatic hydrocarbons (PAHs), and polychlorinated biphenyls (PCBs)

• Contain other compounds: Arsenic, cadmium, chromium, mercury, nickel, vanadium, zinc, and additional volatile organic compounds (VOCs)





Air emissions from tire-derived fuel (TDF)• TDF often used as 10-20% supplement to traditional

solid fuels (coal, wood, and coke)• TDF produces slightly less CO2 than municipal solid

waste, wood, and coal• TDF pollutants of concern include:

– Zinc• Three times higher with TDF than with natural gas• Several orders of magnitude greater than other metals

– Total particulate matter– Trace amounts of dioxins/furans

• Emissions may increase during periods of startup, shutdown, and equipment malfunction





TDF emissions research• Data describing emissions from older or

poorly operated TDF facilities are lacking• Research is continuously evolving• Many technical considerations under the

Clean Air Act are under development• Testing protocols and emissions standards

have not been developed for all potential emissions





Human health effects of TDF emissions• Contaminants with greatest potential to do

harm:– Zinc

• Inhalation in dust or fumes • Acute Immune System impacts - “Metal Flume Fever”• Chronic effects unknown

– Particulate matter• PM10 and PM2.5 can become lodged in the lungs

– Dioxins and furans• Highly toxic to humans• Trace amounts can cause irreparable harm





Particulate Matter• The EPA has identified health effects associated with

particulate matter as including: – Premature death, acute respiratory symptoms, asthma,

chronic bronchitis, decreased lung function/shortness of breath, and straining of the heart.

• The health effects of particulate matter inhalation may not be immediately noticed and can be exacerbated by continuous exposure.

• Toxic compounds such as heavy metals can bind to particulates and enter the blood stream and affect other organs such as the liver or kidneys.





Dioxins and FuransTwo closely related classes of chemicals• Highly persistent in the environment, extremely toxic, known human

carcinogens • Not intentionally manufactured; are a byproduct of the combustion of

chlorinated compounds.

Exposure can result in:• Chloracne; liver damage; changes in glucose metabolism; changes in

hormone levels; weakening of the immune system; weight loss; nervous system disorders; reproductive damage; and birth defects

Trace amounts in the air emissions could enter the food chain • Contamination of downwind food crops and livestock pastures

Build up in fatty tissue • Accumulate substantially up the food chain• Found in human breast milk





Risk management and minimization• Public participation• Fire prevention planning and training • Emergency control strategies • Use of best available technologies for the combustion system to

ensure efficient and complete combustion of TDF • Use of best available technologies for the control system to

ensure complete entrapment of particulate matter and metal emissions

– Fabric filters – Electrostatic precipitators

• Baseline testing and trial burns• Regular monitoring of emissions of compounds recognized as a

priority for TDF ambient air quality monitoring• Unannounced site visits and monitoring to ensure compliance

and to build public confidence





• Canada, Sweden, Finland, and South Korea are leaders in tire disposal

• EU landfill directive eliminates whole scrap tires from landfills by 2003, all scrap tires from landfills by 2006

• U.S. – Mexico Border Environmental Relations– La Paz Agreement; IBEP; Border XXI; Border 2012– Attempts to harmonize environmental issues along border– State initiatives– BECC initiatives

International framework





History of U.S. tire regulation• Evolved from public recognition of problem in 1980’s

– Winchester tire fire• Little federal regulation exists

– Scrap tires are classified as solid waste– Managed by states

• Transport, landfill, storage, and incineration permits / restrictions• Manifest programs• Fees• Subsidies for recycling and end use options• Financial assurance

• Aspects of tire disposal and incineration are subject to federal regulation– SWDA, RCRA, CAA





U.S. laws regulating tire incinerationU.S. Law Year Key ProvisionsSolid Waste Disposal Act (SWDA)

1965 Established grant programs to support application of improved disposal methods and the development of solid waste plans by the states

Resource Conservation and Recovery Act (RCRA)

1976 (most recently amended in 1996)

Amends the SWDA. Governs municipal waste disposal and landfills

Clean Air Act 1970 1990 amendment contains Title V Permit Program for air pollution. Governs air quality standards and major sources of pollution





State permitting processes for Clean Air ActArizona Arizona Department of Environmental Quality

Permit approval takes from 124 days to 479 days, depending on type of permit, complexity, and whether a public hearing is held; fees are determined based on industry and quantity of emissions.

California State is divided into 34 air districts, each of which issues its own permits and has its own regulations. The Air Resources Board oversees districts.

New Mexico

New Mexico Environmental Department oversees permitting process and has a universal application for New Source Review and for operating permits.

Texas TCEQ oversees permitting process; all sources of air pollution must obtain New Source Review permits; large sources of air pollution must also obtain operating permits.





Summary of U.S. state tire initiatives

Annual generation (millions)

# tires in stockpiles (millions)

Whole tires

banned from

landfills?

Cut or shredded

tires banned

from landfills?

Subsidies/grants/loans

Marketincentives

Arizona 5.13 0 Yes Yes

Funds to counties to contract with private scrap tire collectors/

processors

None

California 33.87 2 Yes NoGrants and loans

available for scrap tire operations

5% purchase price preference for state

purchases of recycled products. Retreads required on state

vehicles.

New Mexico 1.82 0.24 No No

Rubberized Asphalt Fund; cost

reimbursement for tire recycling centers

5% price preference for state purchases of

recycled products

Texas 20.85 58 Yes No None None





Mexican environmental regulations

• Ley General de Equilibrio Ecológico y Protección al Ambiente (LGEEPA)– Defines hazardous wastes– Sets policy goals– Outlines obligations of federal government

• LGEEPA has been revised many times• Permitting and enforcement agency

– SEMARNAT





Scrap tire regulation in Mexico• Incineration has been federally regulated since 2002; disposal and

storage are managed by states• Norma Oficial Mexicana NOM-040-ECOL-2002, Protección

Ambiental-Fabricación de Cemento Hidráulico – Niveles Máximos Permisibles de Emisión a la Atmósfera – Current use in kilns– Illegal burning of alternative fuels throughout the country

• Ley General para la Prevención y Gestión Integral de los Residuos – Passed in October 2003, requires waste management plans for

significant waste streams, including tires• State regulations

– Current efforts– New Norma to help states manage tire jurisdiction





Mexican laws pertaining to scrap tire incinerationMexican law Year Key provisions

Ley General de Equilibrio Ecológico y Protección al Ambiente (LGEEPA)

1988 Establishes authority of federal government to manage wastes; sets general environmental policy and strategy

Revisions to LGEEPA 1996, 2000 and others

Amends LGEEPA, orienting its strategy towards recycling, reuse, and energy recovery; sets hazardous waste categories and gives jurisdiction over less hazardous wastes to states

NOM-040-ECOL-2002 (Protección ambiental-Fabricación de cemento hidráulico-Niveles máximos permisibles de emisión a la atmósfera)

2002 Sets emissions limits and monitoring requirements for cement kilns burning alternative fuels; divides alternative wastes into categories; regulates emissions based on type of waste and percentage used





Emissions monitoring for cement kilns using alternative fuels

Percentage of alternative fuel substituted for

conventional fuel (%)

Tires Recoverable combustibles

Formulated combustibles

0-5 None None Level 1

5-15 Level 1 Level 1 Level 2

15-30 Level 1 Level 2 Level 3

> 30 Level 2 Individual validation





General Certification Criteria

• Tire-to-energy, civil engineering, and ground rubber projects would all meet goal of solid waste reduction

• Tire-to-energy as well as gasification would also meet key objective of creating a waste-to-energy project

• Emissions controls for particulate matter and zinc may be required at a tire-to-energy facility to comply with U.S. and Mexican laws





Human Health & Environment Certification Criteria

• Tire-to-energy projects could comply with this criteria• Do tire-to-energy projects offer the “high” level of

protection required?• A tire-to-energy project may have cross-border impacts

and require an additional environmental assessment• Civil engineering projects would rate high in this category,

although leaching and “hot spots” must be guarded against

• Ground rubber applications would rate very high in this category





Technical Feasibility Certification Criteria

• Some stockpiled tires may not be usable for many processed tire applications, particularly ground rubber projects

• Supply of tires may challenge the requirement for adequate resource inputs

• Training of locally available labor should be included in project plans





Financial Feasibility Certification Criteria

• Tire-to-energy projects are currently the most economic

• Civil engineering projects can also be financially viable

• Ground rubber projects could be financially viable, but initially may require public grants or subsidies

Financial feasibility is highly dependent on tire supply, system location, energy prices, and labor and operating costs





Community Participation Certification Criteria• Tire-to-energy projects may be met with considerable

public skepticism• Civil engineering and ground rubber projects would

generate less public concern• Transparency of the project plan and sponsor

communications is critical• At public forums, alternative solutions as well as the “no

action” alternative should be discussed• Instituting a public comment period for proposed scrap tire

projects would facilitate participation





Sustainable Development Certification CriteriaSustainability rankings:1. Retreaded tires2. Civil engineering applications3. Ground rubber applications4. Whole tire incineration5. Shredded TDF incineration6. Landfilling shredded tires7. Landfilling whole tires8. Gasification9. Pyrolysis





Overarching themes• Critical tire management strategy—to eliminate scrap

tire piles• Fire prevention planning and training is paramount for

existing tire stockpiles• All options discussed (tire-to-energy, civil

engineering, ground rubber) have the potential to be certified under the BECC criteria

• If economically feasible, civil engineering and ground rubber projects would be the most socially and environmentally sustainable

scrap tire disposal and recycling options

Documents

scrap tire disposal

tire shreds

tire chips

used tires

total scrap tires

scrap tires worldwidedepending

tires consumeddisposed

so2tirederived fuel