PROJECT DESCRIPTION
BACKGROUND
Expanded polystyrene (EPS) foam is used extensively throughout Europe as an insulation material. At the moment of developing the PSLoop project, the amount of EPS construction waste equaled 200 kilotonnes per year in Europe and was increasing, eventually even up to 1 000 ktonnes per year in the decades to come. Some 52.5% of this waste was incinerated and the energy recovered, while only 7.5% of EPS waste was recycled. The rest was landfilled or incinerated without energy recovery.
EPS that was produced before 2015 contains the flame retardant Hexabromocyclododecane (HBCD), which has been listed as a Persistent Organic Pollutant. A product is no longer allowed to contain more than 100 parts per million of HBCD. Recycling of EPS construction waste is already challenging because of the pollutants (glue, cement residues, etc.) contained within it. Removing HBCD increased the challenge to recycle or even upcycle demolition EPS, because most of the buildings demolished nowadays, do contain this flame retardant in its insulation layers.
OBJECTIVES
The objective of the PSLoop project was to recycle EPS construction waste and to demonstrate an economically viable alternative to incineration. The recycling process the project proposed, is based on the dissolution of PS foam and the removal of the HBCD. The process delivers a PS gel ready for use as a raw material for EPS or XPS. The gel is dried, after which a granulate comparable to virgin material is the end product of the PSLoop process. Bromine is recovered from the HBCD fraction and recycled.
The project intended to construct a recycling plant to demonstrate the process on an industrial scale; the process was already proven to be functional at the laboratory scale. The process has been designed to deal with different qualities of input material to maximise internal recycling of the solvent used and to obtain optimised polymers that are in line with virgin quality PS as an output. In addition, the project was working to create a value chain for EPS/XPS with recycling and collection companies by demonstrating a standard collection and pre-treatment system.
The project's climate action implication was expected to be substantial, given that the PSLoop value chain would be much more energy and resource efficient than the production of PS from virgin raw materials. Furthermore, the project contributed to the Circular Economy Action Plan, the Roadmap to a Resource Efficient Europe and the Waste Framework Directive, as it worked towards creating a value chain for EPS. It also contributed to the implementation of the REACH regulation by reducing the impact of chemicals on the environment or human health through their substitution with safer substances.
RESULTS
The overall aim of the LIFE PSLoop project was to prove that demolition polystyrene (EPS) contaminated with HBCD could be recycled at an industrial scale with the CreaSolv (or PSLoop) method. At the end of the project, the demonstration plant was supposed to recycle at a rate of 3,000 T/year, recover 99% or more of the intake polystyrene, and create usable polystyrene granulate with less than 100 ppm HBCD. Doing this had to lead to the production of 2,100 T recycled PS granulate and 43 T of bromine (to be re-used by AB ICL) during at least one full year of operation. In addition, the project intended to vary with input streams and test the method with other polystyrene containing materials.
At the end of the project, the PSLoop demo plant produced polystyrene granulate of an appropriate quality, but not at the industrial scale and through a continuous process. Thus, the recycling rate of 3000 t/year has not been achieved. The total amount of HBCD containing EPS upcycled has not been communicated. The HBCD content in the recycled polystyrene achieved the <100ppm threshold. The expected amount of recycled polystyrene and collected bromine has by far not been reached, because the demo plant did not operate continuously on an industrial scale for at least one year. The foreseen variety in input streams was not tested during the project period. The total amount of upcycled polystyrene sold in the months after project closure was around 50 tons (according to the Appeal letter of September 2024).
Several of the objectives were not achieved at the early termination date of 30/11/2023. Nevertheless, the PSLoop demo plant provided evidence that the PSLoop method works and could eventually be upscaled to the industrial level. Critical points remain the lack of a financial-economical assessment of the process and a lack of a thorough life-cycle analysis (LCA) of the process. Both were foreseen but not delivered because the demo plant did not operate on an industrial scale when the project ended.
The fact remains that recycling existing demolition EPS is likely to be a better solution than burning it in special installations at extremely high temperatures, which is necessary due to the HBCD it contains. As the PSLoop process has proven that it delivers the right quality output polystyrene granulate, it depends on the polystyrene companies to balance the costs and benefits of using this recyclate. In addition, it depends on the European and national environmental policies and their enforcement, if a business case exists for the recycling of HBCD containing demolition EPS. From 2030 onwards EPS must contain a certain percentage of recycled polystyrene, which is likely to support the business case of the PSLoop process.
