Over 300 commercial glass melting furnaces have been successfully converted to oxy-fuel firing worldwide since 1991 when the first full oxy-fuel conversion of a large container glass furnace took place.  The main benefits for oxy-fuel conversion are fuel reduction, glass quality improvement, emissions reduction (NOx, SO₂, particulates), and productivity improvements.  However, despite the demonstrated benefits of oxy-fuel use in glass furnaces and significant penetration of oxy-fuel in the specialty glass furnaces, only about 60 container and float glass furnaces have been converted to oxy-fuel firing, while most of large soda-lime glass furnaces are still fired with air using large regenerators to recover waste heat in the flue gas.  The primary reason has been economic – with the prevailing environment of low natural gas prices in North America and Europe, the nominal 10% savings in fuel from switching to oxy-fuel is more than offset by the additional cost of using oxygen.

More recently though, there has been an increased emphasis on sustainability and lowering CO₂ emissions.  As a result, process industries – refineries, steel mills, cement kilns and glass furnaces are looking for ways to substantially reduce CO₂ emissions from their operations.  More specifically, several glass companies (container, float and fiberglass) have made definitive commitments for CO₂ reduction as part of the Science Based Targets Initiative.

This emerging trend could substantially strengthen the case for oxy-fuel glass melting.

Flue gas typically exits the oxy-fuel glass furnace at 1450 – 1500^oC.  With full flue gas heat recovery, fuel consumption is estimated to decrease by 20 – 30% with a corresponding reduction in CO₂ emissions, thereby enabling glass companies to meet their 2030 CO₂ reduction milestones.

This webinar will be provided by S. Chakravarti  and H. Kobayashi from Linde PLC