The recycling of composite profiles for cement manufacture takes place in a closed loop in which 30% of the composite is used as an energy source and 70% as a raw material. In this recycling application, granulated composite replaces fossil fuels and is used as a substitute for new raw materials.

In 2010 Fiberline became the first Danish enterprise to join forces with the German company Zajons, which has established a plant in north Germany to preprocess composite for recycling. A grinding mill at the plant reduces the composite to granulate, after which the calorific value of the granulate is adjusted by blending with other recycled materials in a patented process. The finished product is used as a substitute fuel and raw material by Holcim, one of the world's leading cement manufacturers.

The recycling of one thousand tonnes of Fiberline profiles in cement manufacture saves up to 450 tonnes of coal, 200 tonnes of chalk, 200 tonnes of sand and 150 tonnes of aluminium oxide. And no dust, ash or other by-products are formed in the process. (Ref. Holcim, 2010).