Chae TY  Lee JW  Lee YJ  Yang W

Vol. 28,  No. 2, pp. 117-122, Jun.  2022
10.7464/ksct.2022.28.2.117

Coal LNG NOx emission Particulate Matter Coal burner

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This study developed and tested an ultra-low NOx burner in an 80 kW combustion furnace. The experiment was conducted in an 80 kW single burner combustion furnace with changing the swirl numbers, total equivalence ratios, and primary/secondary oxidizer ratios. In this study, liquefied natural gas (LNG) was used as an auxiliary fuel to significantly reduce NOx production. In a thermal power plant, the amount of NOx generated during coal combustion is about 300 ppm. However, using the burner tested in this study, it was possible to reduce the amount of NOx generated via LNG co-firing to 40 ppm. If the input amount of the primary oxidizer is enough for the gas to be completely combusted and the gas and coal are added simultaneously, the combusted gas forms a high-temperature region at the burner outlet and volatilizes the coal. As a result, the N contained in the devolatilized coal is discharged. Therefore, when the coal is subsequently burned, the amount of NOx produced decreases because there is almost no N remaining in the coal. If a thermal power plant burner is developed based on the results of this study, it is expected that the NOx generation will be significantly lower in the early stage of combustion.