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Show Introduction Low NOx High Temperature Burners Robert V. Gemmer Senior Technology Manager The Gas Research Institute Chicago, Illinois, USA The Gas Research Institute is the research arm of the natural gas industry in the United States. GRI conducts cooperative research, development and deployment of technologies and information to measurably benefit gas consumers and the gas industry. Programs are conducted on a wide range of topics, from exploration and drilling of natural gas to its use in homes and industry. A significant portion, nearly 50%, of GRIls annual budget of approximately 200 million US$ is devoted to enhancing the end use of natural gas, and of that, over one fifth is applied to developing industrial technologies that enable the use of gas as the fuel of choice. In 1991, nearly 45% of the 20 quadrillion cubic feet of gas used in the United States went to process heating and steam generation in industry. Because of the importance of industrial gas use to the US gas industry, as well as to the general economy, a great deal of concern was generated on the passing of the Amendments to the Clean Air Act in 1990. Much of this concern was about the impact of the more stringent emissions regulations on the use of gas in industry. Natural gas is recognized as a "clean" fuel. Even so, it can be the source of undesirable emissions. In particular, nitrogen oxides, or NOx, are emitted to varying degrees when gas is burned. NOx are identified in the Clean Air Act Amendments (CAAA) as criteria pollutants because of their role in ozone and smog formation. Control of NOx emissions is mandated by law. High temperature processes present a particular challenge to designers of low NOx combustion equipment. Because the process temperature itself is high, frequently approaching the 2600 F threshold for thermal NOx formation, very careful control of the combustion process is necessary if the application of expensive post-combustion cleanup is to be avoided. In general, it is preferable to do as much as possible in the combustion zone to reduce NOx, since even advanced burner designs are many times less expensive than selective or non-selective catalytic NOx reduction technologies. Excluding steam generation, high temperature industrial processes are the heaviest users of natural gas. Because of the threat to gas use in high temperature processes presented by NOx emissions regulation, GRI has been supporting research since 1989 1 |