Address:
Glafo, Box 5157,
SE-350 05 Växjö
SWEDEN

Visitor's address:
Vejdes plats 3

Tel: +46 10 516 63 50
E-mail: info@glafo.se

You find a map at the
"about Glafo" page.

RE-USE OF COLOURED CULLET (P9907)

The aim of the project is to investigate how to re-use some of the cullet that today is rejected because of the content of coloured glass.

Background
Rejected glass, which originates from for example waste in the production, is taken to waste storage. That means heavy expenses for the glass industry and is not in line with their ecopolicy. A great deal of the rejected glass is considered to be of no use as it contains coloured glass.

Possible re-use
It could be possible to re-use the coloured cullet as an addition to clear glass. One condition is that the connection between different cullet qualities, physical decolouring additives and accepted grey tone for different product groups is established.

To hide the discoloration in clear glass, which is caused by the re-used coloured cullet, decolouring agents are added, which gives a neutral grey tone to the glass. It is important that the glass gives a good impression. Therefore we have to find a balance between how much cullet and decolouring agents that could be added without deteriorating the appearance of the glass.

Realisation
A constant amount of cullet is added to the clear glass. At the different melting tests decolouring agent and percentage are varied. The colour of the glass is measured photometrically and the colour tone is determined by means of a CIE L*a*b colour coordinator. The results of the colour system’s coordinates and added percentage of decolouring agent are used to perform a calculation model for how much decolouring agent that has to be added to get the required decolouring tone in the glass.


CURRENT PROJECTS