THIS CONTENT IS BROUGHT TO YOU BY SINTEF - read more
The construction sector must learn to reuse plastic insulation after demolition
Tonnes of reusable polystyrene ends up as plastic waste when buildings are demolished. Researchers want to see more recycling and reuse.
With strict energy requirements for buildings, we are using more insulation than ever before. Every year, we manufacture and import tens of thousands of tonnes of plastic pellets for the production of insulation materials. At the same time, we dispose of and incinerate insulation equivalent to one-third of what we use.
“ To prevent such large amounts of plastic waste from being incinerated or ending up in landfills, we need to develop new systems for waste sorting and disposal, as well as for the reuse and recycling of building materials. This will benefit both the industry and the environment,” researcher Birgit Risholt says.
She is a senior research scientist at SINTEF and leads the project Circular EPS, which aims to recycle EPS insulation materials from the building and construction industry. EPS refers to expanded polystyrene.
- Expanded polystyrene (EPS), also known as ‘white cork’, has many applications, including as building insulation. It contains 98 per cent air and thus has a very low density and excellent insulation properties. It also exhibits low humidity absorption, high compressive strength, and is extremely durable.
- More than half of all EPS that is manufactured is used in the building industry, and material from this source also accounts for more than half of all EPS waste.
- In 2020, Norway produced a total of 70,000 tonnes of plastic pellets for insulation materials, and imported about 9,000 tonnes. In the same year, we generated 30,550 tonnes of EPS waste. It is estimated that half of this waste was sent to combustion plants, and the other half to landfill.
(Source: The Norwegian Environment Agency (link in Norwegian))
A circular economy value chain will improve access to insulation materials and reduce the need for costly waste disposal after demolition.
The goal is to adapt reusing and material recycling for the future. The work is being done in collaboration with the building industry.
“It will also result in the better management of natural resources, less environmental damage, and lower greenhouse gas emissions,” Risholt says.
Polystyrene is well-suited for recycling
The global demand for polystyrene in construction is increasing, mainly due to energy efficiency efforts.
In essence, polystyrene is made of entirely recyclable materials and is thus highly suited for reuse. In many cases, the plastic insulation will outlast the building it is used in.
Non-contaminated materials should be usable for new insulation applications, ground up for use in new products, or recycled into new raw materials.
“As part of this project, we’ll be analysing used EPS and identifying methods of recycling that ensure circular and sustainable resource use," Risholt says.
The entire industry must be involved
Project owner BEWI (formerly Jackon) is one of the companies that supplies building systems and insulation solutions to the building and construction industry. Now, they aim to lead the way in using recycled materials.
BEWI's goal is to use 50 per cent recycled raw materials in EPS production, which is more ambitious than current regulatory requirements. To achieve this goal, they need access to a significant amount of EPS waste from the construction sector, both from new-build projects and demolitions.
Used expanded polystyrene (EPS) can be recovered from buildings throughout Norway. It takes up a lot of space and is thus expensive to transport. Used EPS may also be contaminated with dirt or chemicals. For these reasons, a logistics system is needed to compress used EPS before transport, as well as a system to sort out contaminated materials.
“In order for us to get hold of sufficient used EPS, the entire value chain will have to get behind the new approach. We can never have enough partners,” Tone-Cecilie Lie says. She is a senior sustainability manager at BEWI.
Assessing the potential for reuse
Ín this project, SINTEF is responsible for assessing existing building stock to determine how much EPS there is and the potential for reuse. It is also important to assess whether the materials can be reused in their current form, or if they have to be processed in some way. Not everything can be recycled.
“Before we can reuse EPS that is recovered from demolished buildings, we have to make sure that it doesn’t contain any harmful substances,” Risholt says.
For example, we know that some EPS from the 1980s contains brominated flame retardants. We cannot use such EPS in new buildings, the researcher adds.
SINTEF will be testing a variety of technical building solutions involving recycled EPS in its laboratories. Researchers will also assess costs, market scenarios, and the need to adapt regulations to facilitate easier recycling and trading of used materials.
About the project
- Plastic recycling is a political objective, and the control of material flows is crucial to its success. Thus, the aim of the project ‘Sirkulær EPS’ (Circular EPS) is to contribute towards establishing a circular value chain for expanded polystyrene (EPS).
- The project partners BEWI, Optimera, Franzefoss Gjenvinning and SINTEF will be working together to develop new services for waste management, sorting, transport and materials control, as well as creating a construction system and technical building solutions for EPS and XPS (extruded polystyrene) that are adapted to the targeted reuse and recycling of these materials.
- The aim of the project is to enable collaboration along the entire value chain and among all the various sectors involved.
- The project ‘Sirkulær EPS’ is an IPN (Innovation for Business) project and is being funded by the Research Council of Norway, BEWI and the project's commercial partners.
Visit the project website here.
More content from SINTEF:
Active control of wind turbine speed can lead to fewer bird strikes
Could farming these small snails become big business?
Have researchers managed to create the healthiest crisps on the planet?
The aquaculture sector is aiming for better plastic recycling
A tiny liver or a minuscule heart can now grow on a microchip
In Palma, researchers will use VR headsets to encourage residents to participate in developing future neighbourhoods