June 13 - Scientists say the recent discovery of how glass is formed at a molecular level will make it possible to produce high quality glass more efficiently at lower temperatures. Unprecedented visual evidence of the process by French researchers may also help glass manufacturers lower their energy consumption levels. Jim Drury reports.
The art of glass-making goes back 6000 years but the chemistry behind the transformation of powder into super-heated liquid glass has mystified scientists. Until now. This is crystalline powder, heated to a temperature of 1500 degrees Farhenheit, transforming into molten glass, a process recorded for the first time. Created by French scientists, this unprecented visual record, unravels the mystery of glass production and opens new possibilities for the industry. Merging hundreds of X-ray CT images they have shown how different grains move and fuse into molten glass at high temperature. The team was led by Emmanuelle Gouillart. SOUNDBITE (English) EMMANUELLE GOUILLART, LEAD SCIENTIST FROM THE CNRS-SAINT GOBAIN JOINT RESEARCH UNIT, SAYING: "The movie that was made was done by selecting one vertical cut into each of these cubes that we get directly from the tomography experiment and just making a movie out of these cuts, one cut per temperature.....Our research aims at understanding better the chemical reactions during glass melting and the interaction between the chemistry and the granular micro-structure." That understanding could have a significant impact .Glass-making is expensive and costly to the environment. On an annualised basis, worldwide production consumes as much energy as the entire electricity use of a medium-sized country. The team's CT images confirm the importance of good contact between the sand, sodium and calcium carbonate grains required to make glass...contact that might be achievable at lower temperatures. The discovery raises the prospect of manufacturers developing faster, more environmentally neutral, techniques. SOUNDBITE (English) EMMANUELLE GOUILLART, LEAD SCIENTIST FROM THE CNRS-SAINT GOBAIN JOINT RESEARCH UNIT, SAYING: "It might be possible, if we understand better the order of the reactions, maybe to lower the temperature of glass furnaces by 50 degrees....Up until now it's really science fiction to say that 100 degrees would be possible....but it might be one of our goals in the future." The research was carried out by the French National Centre for Scientific research and glass manufacturer Saint Gobain. Glass was first developed in the Middle Eastern kingdom of Mesopotamia in 3500 BC. Production methods haven't changed much since then but manufacturers are taking a close look at the new research, and the possibility of giving their ancient industry a new edge. Jim Drury, Reuters