How Are Tyres Recycled?

Over 50 million tyres (just over 480,000 tonnes) were scrapped in the UK in 2001 and around 80,000 tonnes was disposed of in landfill. When disposed of in landfill sites, tyres in large volumes can cause instability by rising to the surface of the site, affecting its long term settlement and therefore posing problems for future use and land reclamation. Rubber materials contain proportions of organic chemicals and little is known about the long-term leaching effects of these materials.

Tyres account for around 3.5% of the weight of an average vehicle, and as a controlled waste under the Environmental Protection Act 1990, a Duty of Care is placed upon waste producers to ensure that waste material is disposed of safely through registered carriers to licensed sites. According to the Used Tyre Working Group's 2001 survey 22% were recycled, 8.3% went to energy recovery, 9.9% were retreaded, 16% were reused and 3.3% were used in landfill engineering. The remainder (approximately 40%) will have been landfilled, stockpiled or illegally disposed of.

There are many ways tyres can be recycled in their original form;

• Reuse of part-worn tyres
  Extracting the maximum safe life from a tyre saves valuable resources (oil, rubber, steel etc).
• Reuse through landfill engineering
  Whole tyres can be used in the preparation/construction of landfill sites, where they are used as leachate draining systems.
• Tyre Retreading
  Tyre retreading is a major industry in the UK. Colway, now C-Tyres, processed 1 million tyres in 1999. Manufacturing a retread tyre for an average car takes 4.5 gallons less oil than the equivalent new tyre and for commercial vehicle tyres the saving is estimated to be about 15 gallons per tyre. Car tyres can only be retreaded once but truck tyres can be retreaded up to three times.
  
  

However when they can't be recycled in their original form they can be chipped. TyreGenics, the UK and northern Europe’s only cryogenic tyre recycling company has officially opened in Baglan, Neath Port Talbot, Wales. The £4m facility (£1.4m of which came from a grant from the European Union’s Objective One fund in support of the jobs and commercial opportunities) will process in excess of 9 000 tyres a day, amounting to 30 000 tonnes a year which would have otherwise been disposed in landfill or in some cases burned producing toxins. The launch follows on from a statement from the Environment Agency in 2003 that urgent action was needed to cut the number of tyres dumped illegally in Welsh beauty spots.

"The volume of tyres being recycled was the equivalent of all the tyres produced in Wales annually. Instead of those going for landfill, drainage or being burnt in cement kilns, they are getting recycled into usable product"
Nick Wyatt, TyreGenics

So how are tyres recycled?, first they are collected and reprocessed by shredding the tyres into millions of tyre ‘chip’, pieces of rubber approximately 50mm x 50mm that have a variety of uses. In the case of TyreGenics, this process is complete by their venture partner Credential Environmental, this company will also collect tyres for recycling in most parts of England & Wales.

This tyre ‘chip’ is the raw material for the cryogenic recycling process. The ‘chip’ is loaded into an enclosed freeze chamber cooled using quantities of inert liquid nitrogen. The 17m chamber takes the chip, cooling all the way along the 15 minute journey, to banks of mechanical hammers. When the chip reaches the hammers, it has been cooled to a temperature of –80 degrees centigrade where the rubber becomes very brittle. The hammers are enclosed in large steel chambers mounted some 2.5m below ground level, where drive shafts running through the chambers propel the hammers to strike against themselves thousands of times each minute. As these hammers hit the frozen tyre chip, they smash rubber off in pieces of various size (known as grade) of tyre ‘crumb’. This crumb is then extracted from the hammer chambers and graded and sorted within the plant into one of 6 grades of crumb for further treatment or direct use.

The process delivers three end products; rubber crumb, steel and fibre.

• The main by-product is rubber crumb, separated and graded for a variety of uses. Around 70 percent of the plants output is used by Field Turf Tarkett who designs and manufactures the surfaces at some of the world’s most famous sporting clubs and stadia including the Denver Broncos, New York Jets and Barcelona’s Nou Camp. Other uses for the crumb include as a component in the manufacture of durable recycled safety flooring systems, within specialist sound insulating wall coverings and in the manufacture of other rubber products.
  
  
• Annually the 4000 tonnes of steel that is recovered during the process at the plant is used by Welsh steel works to produce a wide range of steel products.
  
  
• Annually the 6000 tonnes of fibre extracted during the process is recovered and is currently sent to landfill, but soon hopefully to be used to produce energy. Other potential uses include insulation and cattle bedding.
  
  

If you have Tyres that need recycled find a company that can take them off your hands.