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Show Log NOx, ppm (3" Oxygen) Altex Burner Results zooo .-------------------------------------~ 1,000 500 200 100 50 20 Conventional -----~mM--- -- ------------------- • ·----------- -- -~--*-*-~*i-----i-- " :'i< -------------------- ~~~- ---- 10 ~----~----~----~----~----~------~ o 500 1,000 Combustion Air Temperature degF Figure 5 1,500 regenerative and recuperative systems. A prototype design has been prepared, and the burner is ready for evaluation in an operating furnace. However, following an assessment of the business opportunity offered by the steel reheat market, Eclipse elected to withdraw from the program. At this time, GRI and Altex are seeking a burner manufacturer to carry the concept to the market. Moderate Temperature Processes The level of NO x emissions from gas-fired boilers is not as high as for forge furnaces and reheat furnaces. However, boilers represent the greatest users of energy in the United States. As a result, they have been the first technology to be identified in NOx emissions regulations. Boilers and fluid heaters also represent a major gas load. This combination has motivated GRI to invest substantial effort to reduce the impact of NO x regulations on moderate temperature processes. Early industry efforts at NOx reduction for these burners focused on reducing flame temperatures using steam or flue gas recirculation (FGR) in conventional burners. These approaches could easily reduce NOx emissions to around 50 ppm. However, steam injection or FGR represent additional costs to the users, and the regulations have gone well beyond 50 ppm. For example, the South Coast Air Quality Management District in California required <30 ppm for existing 8 |