Recycling of cullet : Challenges in the melting of glass

Ecological constraints, especially the limited availability of landfill sites, in conjunction with economic advantages, i.e. energy savings in glass melting, have initiated the large scale utilization of recycled cullet in particular of glass containers. Difficulties result from the incorporation of impurity components such as heavy metals and ceramic particles, and furthermore from the changing organic contaminants giving rise to alterations of the redox state of the glass melt which in turn has an impact on glass melt properties.