According to VTT Technical Research Centre of Finland municipal solid waste can be used as material for design products. In the ReLight project, soiled, used grave candles were turned into high-standard plastic material, which was utilised for making a trial batch of Origo keyrings designed by Eero Aarnio. 85% of the plastic parts originated from the plastic material collected from graveyards.
Even though plastic collected with mixed waste can be used for energy production, recycling it as material would be a more desirable alternative in terms of the environment and material economy. Generally, municipal solid waste is regarded as secondary material. The ReLight project showed, however, that it can be used as material for high-quality design products. In the future, even design products can increase their brand value by using recycled materials.
In this trial, VTT chose to use grave candles, soiled with soot, paraffin and stearin, as raw material. Scouts collected them from graveyards in Tampere, and a school class currently collecting money for a school trip, was invited to VTT to sort the load. VTT recovered certain fractions of the material, cleaned them and ground them to be used for melt processing of a material mixture. The design used for the demo piece was a keyring made in the shape of Origo bright light lamp designed by Eero Aarnio. Injection moulding was performed by Merocap in collaboration with All-Plast, and the idea generation and assembly of the design keyring was conducted by Innolux.
The result was a keyring, where 85% of the plastic parts contain recycled plastic materials from graveyards, with some added fillers and colourants. The keyrings will be displayed at the Habitare Furniture, Interior decoration and Design Fair in Helsinki on stand 7k20 on 9–13 September.
"The demonstration project implemented using grave candles succeeded well. It lays foundations for seeking other potential material flows, and disseminates the know-how gathered through the project for raising the degree of plastic recycling. The rest depends on the attitudes and the will to make things better with a view to the environment. I believe consumers to value products that are of high quality and contain skilfully refined recycled materials," says Satu Pasanen, Research Scientist at VTT.
"In this project implemented with an open mind, we succeeded in combining several ethically sound matters. The challenge is how to make the lighting characteristics of the material suitable for lighting fixtures requiring large amounts of material. Use of recycled materials in lighting fixture applications requires further development", states Jukka Jokiniemi, CEO and founder of Innolux.
The plastic fraction collected from graveyards mostly consists of polyethylene terephthalate (PET) or polypropene (PP). It can also contain small amounts of PVC or plastics filled with fire retardants. The materials can be effectively sorted for industrial use. The plastic fraction can be cleaned, for example, simply by heat treatment, where stearin or paraffin residues are drained from the ground plastic material. Soot particles can be left in the final product to give a certain look for the product, or the material can be lightly coloured to hide the particles.
CAPTION. In the ReLight project, used grave candles were used for manufacturing high-standard plastic material, which was utilised for making a trial batch of Origo keyrings designed by Eero Aarnio. (Photos 1-4: VTT and photo 5: Innolux)