Oxygen Enhanced NOX Reduction
At Praxair, we believe that the advancements we make in glass manufacturing and production today will pave the way for a more sustainable future. Our Dilute Oxygen Combustion (DOC) technology, which lowers emissions from glass furnaces by as much as 90%, is a huge step in the right direction. But were not stopping there. Our DOC technology has succeeded in maximizing energy efficiency, while dramatically reducing NOx and particulate emissions. And we continue to actively explore efficient and economical methods of heat recovery from off-gases to further propel todays glass manufacturing process into the future.
The application of DOC technology in your glass production results in two main environmental benefits: low NOx and low particulate emissions. Converting an air-fired furnace to an oxy-fuel furnace eliminates most of the nitrogen in combustion air, reducing NOx emissions by as much as 90%. With the low flame temperature of DOC technology, NOx emissions are further reduced to one fifth of typical oxy-fuel flames. Auxiliary DOC burner applications can reduce NOx emissions even in air-fired furnaces with high nitrogen concentration. In addition, the conversion to Praxairs DOC oxy-fuel system significantly reduces batch carryover and emissions due to reduced gas volumes.
DOC technology reduces particulate emissions by significantly reducing alkali volatilization in glass manufacturing and production. Studies have shown that volatilization is the main source of particulate emissions for gas-fired glass furnaces. Volatilization of NaOH for soda lime silicate glass is dramatically lowered with Praxairs DOC technology in two ways: reduced water vapor concentration at the glass combustion interface, and lower impinging velocity of combustion gases.