ANR 3VER : Towards more Virtuous Glasses

Project funded by Agence Nationale de la Recherche (ANR)

Glass is a highly versatile material that has been ubiquitous in daily life for millennia and plays a key role in future carbon-neutral advanced technologies. However, the current glass production models are not sufficiently environmentally friendly and produce high CO2 emissions.
In order to meet the requirements of a carbon neutral supply chain by the mid-21st century, the challenges for glass lie in CO2-neutral raw materials and melting processes. Currently, almost all glass both on an industrial as well as an artisanal scale, is manufactured in gas furnaces that emit large quantities of CO2, because these furnaces allow great flexibility and constant adaptability of production volume, temperature and redox conditions, all of which have a significant impact on the physical and chemical properties of the final product.

To limit greenhouse gas emissions in all sectors of the glass industry as soon as possible, carbon-free alternatives must be developed for both raw materials and melting technologies. With regard to CO2 emissions and energy consumption, several possible improvements have been explored, such as (1) increasing the proportion of hydrogen in the gas mixture, (2) using electric furnaces, and (3) re-utilizing cullet as raw material in both the glass and cement industries. Advanced protocols are already in place for the first two alternatives, and the use of recycled materials in industry is already widespread.

What has not yet been explored is the addition of different proportions of volcanic lava to glass cullet (max. 50 wt%) to produce new glass compositions, which would completely eliminate carbonates, one of the main sources of CO2 emissions in the glass industry. In combination with recycled glass, this would drastically reduce the energy consumption of the melting and fusion process. A limiting factor is the working range of glass within the limits of its physical and chemical properties. These restrictions apply equally to glassmakers in ancient times and artisanal
glass makers today, as it does to industrially manufactured glass. Specifically, the various glass working processes like gathering, blowing and annealing are the same independent of scale and constrained by the working range of glass at high temperature.

Our project 3Ver addresses all these factors and aims to develop new glass recipes in an electric furnace for the carbon-free production of everyday objects. These new compositions will be based on the use of cullet in combination with different proportions and types of volcanic lava to bypass the use of carbonates. The objective is to formalize and adapt the new compositions to the different glassmaking processes, then optimize the new compositions in an electric furnace, and ultimately to translate the laboratory research to an industrial application – from bench to bedside.

In addition to developing new glass compositions, we will be training future generations of master glassmakers to work with these new materials and to adapt to future developments. The research on new compositions and their adaptation to glassmaking crafts will be carried out with all the partners, in particular the Lycée’s teachers and students.