When talking about recycling, the discussion very often centres either on a chemical technology or a mechanical process. However, there is a third option available. It's called physical recycling.
A new recycling plant based on this process has been constructed in Terneuzen, the Netherlands. Scheduled for opening on 16 June, it aims to prove the technical and economic feasibility of a large-scale, closed-loop solution for the recycling of EPS demolition waste, such as insulation.
This waste is not only contaminated with impurities, such as cement and other construction residues, in most cases, it also contains the legacy flame retardant HBCD. Used until 2015, today it is classified as POP (persistent organic pollutant), making mechanical recycling of this type of waste impossible. Under the current regulations, it must be incinerated - a costly proceeding - or physically recycled using the dissolution process developed by CreaSolv.
The process is a physical one, as it leaves the chemical structure of the polymers chains intact - changing only the physical state from solid to liquid, a process, moreover, that is reversible.
It also offers an efficient way to close two loops with one solution.
During the solvent-based process, the legacy flame retardant HBCD, is separated from the polystyrene and safely removed, allowing the valuable bromine it contains to be recovered. This polystyrene can then be recycled for reuse in new insulation materials.
The bromine is re-used to produce new polymeric flame retardants to be applied in insulation products made from the recyclate Loop-PS.
“It’s a real plus that the plant can not only take care of current recycling waste but also legacy recycling waste,” said Jan Noordegraaf, co-director of the plant. “Moreover, we can do this with about the same energy input as mechanical recycling and the energy we use comes from windmills.”
The PolyStyreneLoop recycling plant in Terneuzen will pave the way for the construction of similar EPS recycling plants in the rest of Europe, said Lein Tange, Co-Director of PolyStyreneLoop, the cooperative representing the 75 companies from the polystyrene foam value chain behind the project. The initiative also received funding via a European Union LIFE programme grant.
This first plant in Terneuzen will have the capacity to recycle 3,300 tonnes of polystyrene foam demolition waste per year, validating the technical, economic, and environmental viability of the new recycling process.
EPS is a lightweight foam composed of 98% air and 2% technology with outstanding protective and thermal insulation properties. In addition to building and road construction uses, it is widely used in packaging to protect everything from heavy white goods to sensitive electronics, fresh fruit and vegetables, vaccines and even bees.