Multi-Fuel Low-NOx Burner Development, Phase II

摘要

The objective of this program was to develop high-efficiency, low-nitrogen-oxides producing multi-fuel industrial burners having flame and heat-transfer characteristics that are suitable for specific industrial processes in cooperation with burner manufacturers for process heating applications. Burners for three industrial processes were designed to achieve a reduction in NOx emissions compared with currently used standard burners: (1) A high excess air burner used in direct air dryers for applications in the food processing industry, (2) A hot air burner having high convective heat transfer for direct fired metal processing furnaces, and (3) A hot air burner with a long, luminous flame for direct fired process furnaces in the steel, aluminum, and glass industries. Bench scale tests on catalytic combustors verified the possibility of achieving extremely low-NOx emissions from a burner designed for food drying applications. Unfortunately, the high preheat temperature required for the air/fuel mixture is impractical. The high-convective, hot air burner achieved NOx emission reduction of up to 50%. However, additional work is required to determine whether or not the burner would perform adequately in metal processing applications. NOx emissions from the hot air burner with a long, luminous flame were 45 to 60% lower than the standard burner. Although the flame characteristics were slightly different, they seemed acceptable for many industrial applications.