Cement manufacturer Cemex has been granted permission to double the volume of waste tyres it uses as a fuel at its cement kiln in Rugby.

Chipped tyres awaiting use as a substitute fuel at the Cemex Rugby cement works in Warwickshire.

The Environment Agency has issued a permit allowing the firm to increase the percentage of fuel it replaces with chipped tyres from 12-25%.

Despite Cemex experiencing difficulties in burning tyres at the site in the past, (see letsrecycle.com story), the permission follows a period of "record performance" in which data showed a marked reduction in emissions of oxides of nitrogen by up to 30% when tyres were in use.

The move is expected to bolster Cemex's green credentials and provide a market for 240,000 car-sized tyres. This is particularly important since sending both whole and shredded tyres to landfill was banned last year under European law (see letsrecycle.com story).

Around two million chipped tyres are already supplied to the site by tyre recycling specialist Sapphire Energy Recovery, which is a joint venture between cement giant the Lafarge Group and tyre manufacturer Michelin Tyre PLC.

A spokesperson for Cemex said: "Cemex welcomes the EA decision, which is key to improving the company's environmental performance and will help to ensure that quality cement from the plant is provided as sustainably as possible."

Climafuel

At the Rugby site, over half of Cemex's kiln's fuel can now be replaced from waste-derived products after Cemex also received permission to replace 30% of its fossil fuels with household-waste derived "Climafuel" last month (see letsrecycle.com story) .

The Cemex spokesperson said: "This means that when used together in future, tyres and Climafuel could substitute up to 55% of the fuel used to heat the kiln. This would significantly reduce the carbon footprint of the plant."

Cemex is now planning to gradually increase the use of tyres with immediate effect, and once the trial has been completed, Climafuel will be introduced in a trial which is due to commence in the New Year.

Climafuel is already being trialled at at Cemex's other two cement kilns in South Feriby in Lincolnshire and Barrington in Cambridgeshire, where the firm also burns Secondary Liquid Fuel (SLF) -made up of liquid wastes such as paint and thinners.