The recovery rate for end-of-life tyres in Europe increased from 38% in 1994 to 80% in 2004. Favourable policy drivers and a diversifying range of reuse and recycling options for tyres have been crucial to the phenomenal rise.
by Fazilet Cinaralp
More than 2.7 million tonnes of used tyres were generated in Europe in 2004, reflecting an average annual increase of 2.6% since 1994. Since 2004 and the accession of 10 new Member States to the European Union, this figure has increased still further (to 3.2 million tonnes/year). In response to environmental and economic challenges posed by end-of-life tyres (ELTs), the European tyre industry anticipated the need for an efficient, sustainable and responsible strategy towards their management.
End-of-life tyre arisings and recovery
In 2004 the largest volumes of arisings were in the biggest Member States (Germany, France, Italy, Spain and the UK) where the totals vary between 300 and 600 thousand tonnes per year. All the other Member States have arisings of less than 150 thousand tonnes per year and at least six (e.g. the Baltic states and the Netherlands) have 15 thousand tonnes or less to manage.
The estimated annual cost for the management of these arisings is at least €600 million. This is a high cost for a product that represents a valuable resource of secondary raw materials or energy.
In 2004, 10 European countries successfully recovered 90% or more of their annual arisings. For the same year, the EU-25 had an average recovery rate of 80% while the figure for the EU-15 was 85%. This level of recovery compares favourably with other sectors; for example, in 2004 the European Environment Agency (EEA) published recovery rates of 84% for aluminium and 56% for paper and cardboard.
Management systems
The EC Landfill Directive (1999/31/EC), which banned landfilling of tyres from July 2006, has been a major driver over the past decade for the development of waste management policies at the national level. Although all Member States have to implement the Directive, they are free to manage it in different ways. There are three different systems for managing the issue of ELTs within the EU:
- producer responsibility
- tax system
- free market system.
Producer responsibility
In planning for the implementation of the Landfill Directive, the tyre industry initiated a strategic programme based on extended producer responsibility. It was developed by the European tyre manufacturers (see below) gathered within the European Tyre & Rubber Manufacturers’ Association (ETRMA).
 End-of-life tyre treads waiting for reprocessing. all photos: aliapur |
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European tyre manufacturers
Tyre manufacturers in Europe include:
- Bridgestone Europe
- Continental
- Cooper Tires
- Goodyear Dunlop Tires Europe
- Marangoni
- Michelin
- Nokian Tyres
- Pirelli
- Vredestein
This has lead to the gradual setting-up of national ELT management companies backed with a proper statutory regime. Figure 1 shows the location of these companies, which arrange the collection and ecologically sound treatment of ELTs via the most economic route available. Their ongoing work, both in practice and in research and development, supports a continually expanding knowledge base. Their reporting obligation towards the authorities provides a good example of clear and reliable traceability. For the end-user, this system guarantees transparency of costs through a visible contribution, clearly indicated on invoices.
 FIGURE 1. ELT management companies in Europe. source: etrma |
To date, 14 European countries operate a producer responsibility system for ELTs and, hopefully, this will soon expand to 16 with the inclusion of Italy and Turkey.
Tax system
Under the tax system, each country is responsible for the recovery and recycling of its ELTs. It is financed by a tax levied on tyre production and subsequently passed on to the customer. This is an intermediate system whereby the producers pay a tax to the state, which takes overall responsibility for the organization of the system and remunerates the operators in the recovery chain. This system is applied in Denmark, Latvia, the Slovak Republic and Slovenia.
Free market system
Under the free market system, the legislation sets the objectives to be met but does not designate those responsible. In this way, all the operators in the recovery chain contract under free market conditions and act in compliance with legislation. This may be backed up by voluntary co-operation between companies to promote best practices. Countries such as Austria, Germany and the UK apply this system.
A turnaround in market trends
Over the past decade, there has been a dramatic turnaround in the disposal strategy for end-of-life tyres, with a decline in landfilling from 62% in 1994 to 20% in 2004. This fall looks set to continue as countries improve their ELT management systems and actively seek new and innovative ways to expand treatment capacity. The major markets (Figure 2) benefiting from this turnaround are energy recovery and recycling, with 31% and 28% respectively in 2004.
 FIGURE 2. End-of-life tyre recovery in Europe, 1994-2004 (data up to 2002 includes EU-15; data after 2002 includes EU-25, Norway and Switzerland) |
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Growing market for energy recovery
End-of-life tyres can be used as an alternative to fossil fuels; the calorific power of one passenger car tyre is equivalent to 7.6 litres of oil. The increase in the price of oil and the necessity to preserve resources could favour the development of this type of application.
Combustion industries are currently facing a number of significant issues with the peak in energy costs and the constraints imposed by the introduction of air emission standards. In both these cases, this could create opportunities for tyre-derived fuel (TDF).
Currently in Europe, whole or shredded tyres are used as a supplementary fuel to partially meet the energy demand of the cement industry. The cement sector requires 30 million tonnes of fuel equivalent per year. If all ELTs were sent to cement kilns, this would still only represent 10% of their overall need. In reality, the European cement industry currently restricts alternative (non-fossil) fuels to no more than 20% of its total fuel consumption. But this still leaves significant opportunity for this type of application. In 2004, 981,000 tonnes of ELTs were sent to cement kilns.
Use in thermal power stations is underdeveloped in the EU but much more widespread in the US. Again the elevated cost of energy could create openings for TDF in this sector. At present, its use in pulp and paper mills is not developed in Europe but is quite common in the US. According to the US Rubber Manufacturers Association, 17 pulp and paper mills were consuming 26 million scrap tyres per year by the end of 2003.
The various market segments face different challenges and the rising cost of energy will no doubt remain a critical factor and stimulate market growth for TDF as an alternative fuel.
In the US, a system of standards has been created by the American Society for Testing and Materials (ASTM) for TDF. The improvement in the quality, consistency and supply chain for TDF will enhance its chances of being seen as a valid alternative fuel for the larger customers. One of ETRMA’s current projects is to support the elaboration of a set of standards for cuts, shreds and chips in Europe.
An increased array of recycling applications
In terms of material recycling, civil engineering applications are the main recovery route for whole tyres. Applications vary from coastal protection, erosion barriers, artificial reefs, breakwaters and avalanche shelters to slope stabilization, road embankments, landfill construction operations, sound barriers and insulation. At present the market for this type of reuse is largely confined to single projects and is therefore fairly small in scale. However, this application is under-utilized and could represent a significant growth area for ELTs.
 Wheels for caddies |
Tyres can also be sheared mechanically into shreds ranging in size from 25 to 300 mm. Tyre-derived aggregate (TDA) is used as foundation for roads and railways, as a draining material replacement for sand and gravels, in landfill construction, for fill and embankments; backfill for walls and bridges, and as an insulating under layer for roads. TDA is lighter than aggregate by 30%-50%; it drains up to 10 times better than well-graded soil; and provides eight times better insulation than gravel.
 As flooring for playgrounds |
After the removal of the steel and fabric components, the remaining rubber is reduced to granular rubber. Applications for this material include moulded rubber products such as wheels for caddies, dustbins, wheelbarrows and lawnmowers, urban furniture and signposts.
Crumb and powdered rubber can also be used as:
- flooring for playgrounds and sports stadiums
- shock absorbing mats for schools and stables
- paving blocks or tiles for patios and swimming pool surrounds
- roofing materials.
A promising use of crumb rubber is in the construction of artificial turf, for example, in football fields.
 ELTs used as fill and embankment |
Rubber-modified asphalt takes advantage of the elasticity and noise-absorbing characteristics of the rubber. This material increases the life-span of the road surface, reduces the noise emissions and increases safety in wet road conditions, but is still relatively under-utilized in this area.
Promising new opportunities
2004 saw the emergence in Europe of an important new market for ELTs in steelworks equipped with electric arc furnaces (EAFs). This application was validated for industrial use in France and, in 2006, one industrial site is already capable of processing 7000 tonnes of ELTs per year. This is a promising application, which uses both the carbon and steel content of the tyres. New steel plants have come into operation in other parts of Europe. Figure 3a summarizes the EAF process, and Figures 3b and 3c the electric arc and chemical conversion concepts, respectively.
 FIGURE 3a. Electric arc furnace process. source: arcelor |
Thermal treatment technologies - pyrolysis, thermolysis and gasification - are some of the other emerging solutions for recovering value from ELTs. Tyre pyrolysis involves the thermal decomposition of ELTs into intermediate substances such as gas, oil and char. The economic viability of this alternative route for high-temperature resource recovery from tyres is hampered by the fact that the prices obtained for the by-products often fail to justify the process costs.
 FIGURE 3b. The electric arc concept. source: arcelor |
Under current market conditions, the economic viability of these options has yet to be proved (there are few or no large-scale plants currently in operation), but they have the merit to offer scope for increasing recycling rates.
 FIGURE 3c. Chemical energy conversion. source: arcelor |
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Constraints will not prevent confirmation of the positive trends
The efficient and cost-effective management of ELTs as a valuable and versatile resource with a high potential still has a long way to go. Many countries have successfully achieved a managed transition away from landfilling, but evolving market trends and regulations should not compromise market development.
End-of-life tyres are classified as waste, which undoubtedly creates hurdles for the development of certain markets. According to the application, this classification can create difficulties concerning permits, emissions, transportation and incineration. Even for use in civil engineering applications, this denomination raises problems of perception in the minds of the general public.
Shredding, crumbing or thermal processes have relatively high operational costs and the sale of the by-products (crumbs, textiles and steel) does not always offset the initial cost, creating a need for significant gate fees payable to the granulating industry.
However, ETRMA members are convinced that more research into technologies for improving these market options and development of industry standards under the aegis of CEN (European Committee for Standardization) will undoubtedly contribute further to establishing sustainable markets for ELT applications.
End-of-life tyres are a recognized resource with a wealth of potential. While there is still room for improvement, the European tyre manufacturers are committed to pursue the promotion of best available techniques in the effective recycling and recovery of ELTs. Future trends will surely confirm that their strategy is paying off.
Fazilet Cinaralp is Secretary General of European Tyre & Rubber Manufacturers’ Association (ETRMA) based in Brussels.
Fax: +32 2 218 61 62
e-mail: info@etrma.org
web: www.etrma.org
ETRMA’s End of life tyres, 2006 Report can be accessed at www.etrma.org/pdf/ETRMA_ELTs_report_2006.pdf
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The tyre
The tyre is a complex and high-tech safety product representing a century of manufacturing innovation, which is still ongoing. It consists of many materials - the very best the metallurgical, textile and chemical industries can produce. There is no room for even the slightest defect and it is an extremely complex process to develop and manufacture the product.
From a materials point of view, the tyre is a mixture of synthetic and natural rubber, to which are added a range of specific substances to ensure performance, durability and safety. These include mineral oil, reinforcing fillers (carbon black and silica) and vulcanizing agents (sulphur), which act as catalysts to accelerate the vulcanization process.
Tyres can therefore be used for their calorific value equivalent to that of good quality coal or for their intrinsic quality giving added value to a variety of recycling applications. The characteristics of a tyre contribute in many ways to the broad scope for recovery.
