Millions of used tyres are produced every year by Europe’s vehicles. Some of these can be re-used, but often they must be disposed of.

Credential Environmental, the UK’s leading collector and reprocessor of used tyres, shreds millions into tyre ‘chip’ pieces of rubber approximately 50mm x 50mm that have a variety of uses.

This tyre ‘chip’ is the raw material for our cryogenic recycling process. Every day we take delivery of up to 80 tonnes of chip and put it through our state of the art 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 our 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.

Other materials, including steel and fibre are recovered through the process, and these are also recycled, making the process 100% efficient.