Rampf claims first in making polyols from waste flexible foam
By Liz White, editor
A startling amount of all the flexible foam made globally – up to 30 percent – ends up as process waste, according to Fraunhofer ICT expert Dr Ulrich Fehrenbacher.
Flexible foam is made in huge blocks and then cut to shape/size, leaving a considerable amount of offcuts as scrap. In Germany this amounts to 20 kilotonnes per annum (ktpa), and to about 145 ktpa in the EU (Germany makes 95 ktpa and the EU 750 ktpa of new foam annually), Fehrenbacher said.
About half of all flexible foam made goes into furniture and mattresses, 20 percent each goes into vehicle uses (cars, trains and planes) and the construction sector, with 10 percent going into other uses, according to Fehrenbacher.
He listed three main routes for foam recycling:
- Thermal energy recovery (24-30 MJ/kg);
- Material recycling or rebonded foam (for US carpet underlay, a saturated market and hence a relatively low value product); or
- Chemical recycling (solvolysis).
Glycolysis of rigid foam is an established chemical recycling route, used as an industrial process, while solvolysis/acidolysis for flexible foam is at an early stage, Fehrenbacher told the audience at the FSK meeting in Essen, Germany, 21-22 Nov.
To make rebonded foam, producers grind flaked foams, mix it with a binder and…