Advances in tank melter, refractory, controls, and heat source technology have paralleled progress in glass chemistry, quality, and production scale for decades. These same advances have also led to a revival of the 75-year old concept of bottom heating for glass melting. To create high-intensity heat transfer and rapid melt homogenisation, bottom heating, or submerged combustion melting, uses forced convection and direct contact heat transfer. The work of EU, American and Ukranian scientists has demonstrated that bottom heating offers energy savings, emissions reductions, and cost savings relative to conventional melting. Recent work by the Gas Technology Institute of the USA, in partnership with a consortium of glass companies, has advanced the bottom heating technology for a number of glass products to the brink of commercialisation. With ongoing work a practical, rapid refining process could be developed to enable bottom melting as an alternative melting approach for a broad range of commercial glasses.
