Publications

Effect of furnace operating conditions on alkali vaporization, batch carryover, and the formation of so2and NO in an oxy-fuel fired container glass furnace

MOLINA OCHOA, Alejandro N.; Shaddix, Christopher R.; Blevins, Linda G.; Walsh, Peter M.; Neufeld, John W.

Oxygen-fuel fired glass melting furnaces have successfully reduced NO x and particulate emissions and improved the furnace energy efficiency relative to the more conventional air-fuel fired technology. However, full optimisation of the oxygen/fuel approach (particularly with respect to crown refractory corrosion) is unlikely to be achieved until there is improved understanding of the effects of furnace operating conditions on alkali vaporization, batch carryover, and the formation of gaseous air pollutants in operating furnaces. In this investigation, continuous online measurements of alkali concentration (by laser induced breakdown spectroscopy) were coupled with measurements of the flue gas composition in the exhaust of an oxygen/natural gas fired container glass furnace. The burner stoichiometry was purposefully varied while maintaining normal glass production. The data demonstrate that alkali vaporization and SO2 release increase as the oxygen concentration in the exhaust decreases. NOx emissions showed a direct correlation with the flow rate of infiltrated air into the combustion space. The extent of batch carryover was primarily affected by variations in the furnace differential pressure. The furnace temperature did not vary significantly during the measurement campaign, so no clear correlation could be obtained between the available measurements of furnace temperature and alkali vaporization.