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Show IT -McGill Pollution Control Systems UL TRALOW NOX™ Burner Systems March 18, 1991 Abstract ULTRALOW NOX™ theory and technology has evolved over the past 33 months. The culmination of this work has resulted in a new and revolutionary combustion process and computer designed system that can significantly reduce the production of oxides of nitrogen in all direct fired heat transfer equipment. This paper summarizes both the theoretical concepts of ULT RA LOW NOX™ technology, the hardware involved and the system design approach that has brought the theory into reality. It is now appropriate that this knowledge be made public and contribute to future research and discussion. History Development of UL TRALOW NOX™ Technology ULTRALOW NOX™ development was ajoint effort between experts in the design of direct fired heaters and experts in the design of burners and combustion equipment. The allowable levels of NOx production for fired equipment has been significantly reduced in the Los Angeles, California area by the South Coast Air Quality Management District (SCAQMD). Rule 1146 requires that fired equipment with a heat release below 40MM BTU IHr produce 40ppmv or less of NOx (approximately 0.051b/MM BTU). Rule 1109 requires that fired equipment above 40MM BTU/HR shall produce 0.031b/MM BTU or less of NOx (approximately 25ppmv). Both Rules 1109 and 1146 mandated NOx levels that .were well below the capabilities of existing combustion equipment to maintain on a constant basis for all fuel types and firing conditions. In June of 1988 the IT-McGill research team identified certain goals and objectives that must be achieved in order to create a new technology which would meet the NOx reduction requirements of Rules 1109 and 1146 and would also be commercially accepted by owners and operators of combustion equipment. NOx Reduction Goals and Objectives The following is a summary of the goals and objectives identified by the IT-McGill research team. Nt) To create a burner and/or burner system that would meet O.03Ib NOx per million BTU but would not require fans, \ \ complicated measurement devices, additional instrumentation, catalyst or chemical injection. N2) To utilize the flue gas already in the firebox as an inen medium. From this concept, the terms "natural flue gas recirculation" and ULTRALOW NO? were created. This concept is incorporated in the IT-McGill pending patent. N3) To develop a burner that would exceed existing performance standards for natural draft and forced draft raw gas burners. Commercial Acceptance Goals and Objectives el) SAFETY - Achieve or exceed raw gas burner stability limits over a wide range of oxygen levels and turndown. Never sacrifice safety for NOx reduction. |