Sialon Ceramics and Aktive Arc Últrasonics have made a breakthrough in ultrasonic molten gas technology that can reduce energy costs by 20% and reduce the environmental impact of glass manufacture.
The process uses a new ultrasonic generator and a proprietary ceramic sonotrode to treat large volumes of high viscosity molten glass at temperatures of up to 1,600 degrees Celsius.
“We have developed an ultrasonic gas melt degassing technology which significantly increases the efficiency of this process, reducing the refining temperature and saving up to 20% of the energy cost," Nico Van Dongen, Director of Sialon Ceramics, said.
“Removing gas bubbles from glass during its manufacture is an essential part of the glassmaking process. The gas bubbles form during the glass melting process, which involves several chemical reactions that create the glass.”
The chemical reactions produce large amounts of carbon dioxide and other gasses. Degassing involves bubble agglomeration.
Dissolved gasses diffuse from the melt to form bubbles that rise to the surface and are expelled.
The time this takes depends on the bubble diameter and the viscosity of the melt, which is a function of the melt temperature.
Various methods can improve the efficiency of this process. These range from the addition of fining agents, vacuum fining and even the use of microgravity.
However, the application of ultrasonic-assisted glass refining is highly promising.
Mario Plasencia, Director of Akve Arc Ultrasonics, said: “Our ultrasonic degassing process uses a new ultrasonic generator and a proprietary ceramic sonotrode which can treat large volumes of highly viscosity molten glass at temperatures of up to 1,600 degrees Celsius.
"We carry this out at the forehearth of the glass furnace, placing the sonotrodes directly into the melt. This process allows us to reduce refining temperatures from around 1,450°C to 1,300°C. This is massive, and provides a total energy saving of up to 20%."
