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Show ABSTRACT New, Low NOx Burner Design for High Temperature Process Furnaces R. T. Waibel and S. Napier John Zink Company Tulsa, OK A novel low NOx burner has been developed for radiant wall furnace applications. It is especially suited for applications needing to fire a variety of fuels with ambient or preheated, forced draft combustion air. In the current application, NOx levels less than 0.03 Ib/MMBtu have been achieved with 350 of air preheat firing various mixtures of hydrogen and natural gas. INTRODUCTION The refining, petrochemical and chemical industries utilize a wide variety of furnace designs. One type is sometimes referred to as a radiant wall furnace. It is often used for the high temperature reforming and cracking processes which are used for making hydrogen and ethylene. They are called radiant wall furnaces because the burners are used to heat two of the furnace walls. The walls then heat the process tubes, which are typically located in a vertical row between the parallel radiating walls. The furnace is designed to provide uniform heat transfer along the full length of the process tubes at relatively high temperatures. Exit gas temperatures can range as high as 2400 of, depending on the specific process design conditions. One common method of designing these furnaces calls for several rows of burners that are designed to produce a flat radial flame pattern that is parallel to the furnace wall. This flame, adjacent to the wall, heats the wall to temperatures that can range as high as 2800 OF depending on the fuel composition and process design. A large furnace might have five rows of eighteen burners on each of two sides and a total heat input to the furnace of 180 MMBtu/hr. |