Holcim uses GRP waste to power cement production

Holcim uses GRP waste to power cement production
Published: 20 September 2010

Denmark-based pultrusion processor Fiberline has struck a deal with Holcim and waste-to-fuels company Zajons Logistik Entsorgungsgesellschaft (ZLE) - both located in northern Germany – to supply surplus glass fibre reinforced plastic for thermal recycling in cement production.

Beginning this month, Fiberline is sending its GRP waste to ZLE, which is located 331km away at Melbeck in Germany, where it is shredded and other recycled waste added to achieve a defined calorific value above of the polyester resin alone. The modified waste is then sent on a further 119km to Holcim in Lägerdorf, where the waste is fed into the company’s cement kilns. The waste is used to provide process heat while the glass fibre content substitutes sand.

Based on information from Holcim, Fiberline calculates that recycling 1,000t of its GRP profile waste in cement production saves up to 450t of coal, 200t of chalk, 200t of sand and 150t of aluminium oxide. It also eliminated Fiberline’s GRP waste disposal problem.

Fiberline sustainability manager Benedikte Jørgensen says: “In the short term, this contract marks an important breakthrough for our company, but the next step will naturally be to look at a formalised collection scheme that also meets customer and user needs by ensuring that their GRP waste – such as life-expired low energy windows – will not simply pile up but be recycled”.

Jørgensen was referring to the Fiberline translucent GRP pultruded window profiles that it first showed at the Fensterbau Frontale 2006 fair in Nuremburg, Germany.

Prior to the development of this thermal recycling route into cement production, recycling of GRP has been limited to grinding into fine and coarse fractions to partially substitute mineral filler and glass fibre reinforcement in new GRP formulations such as BMC (bulk moulding compound) and SMC
(sheet moulding compound).

ZLE has decided in 2008 to invest €4m to build a second plant for alternative fuel production at its Melbeck headquarters, increasing total annual capacity from 50,000 to 200,000 tonnes. The new plant will be designed to process windmill rotor blades into fuel. ZLE claims the Melbeck plant will be the largest alternative fuel plant in Germany.