Reinforced mixed type gas low-nitrogen burner for aluminum hydroxide roasting furnace

Abstract

The invention provides a strengthened mixed type fuel gas low-nitrogen burner for an aluminum hydroxide roasting furnace, which comprises a burner body, the burner body is fixed on a furnace wall through a flange I, the burner body comprises a burner gun barrel and a burner gun head, the tail end of the burner gun barrel is communicated with a fuel gas supply pipe through a flange II, and the tail end of the burner gun barrel is communicated with a fuel gas supply pipe through a flange II; the head end of the burner gun barrel is fixedly connected with the burner gun head, the burner gun head extends into a furnace wall, a plurality of gas spraying holes are formed in the spherical surface of the burner gun head, and the sum of the areas of the gas spraying holes located in the center of the spherical surface is larger than the sum of the areas of the gas spraying holes located in the non-center of the spherical surface. And the sum of the areas of the gas spray holes is gradually reduced from the central position of the spherical surface to the two sides. Non-uniform distribution of fuel gas is achieved, the flow of the fuel gas injected to the center of the hearth is increased, the amount of fuel injected to the position near the furnace wall is reduced, the mixing effect of the fuel gas and air vertically flowing from bottom to top is enhanced, and generation of thermal NOx is reduced.

Description

technical field [0001] The invention belongs to the technical field of low-nitrogen combustion, and in particular relates to an enhanced mixed gas low-nitrogen burner used in an aluminum hydroxide roasting furnace. Background technique [0002] The existing domestic production capacity of aluminum hydroxide roasting furnaces is 90 million tons per year, accounting for more than half of the world's production, and the number of roasting furnaces is about 100. At present, domestic aluminum hydroxide roasting furnaces are mainly suspended roasting furnaces. Natural gas and low calorific value coal gas are diffused and burned at a preheated air temperature of 600-750°C. The flue gas temperature after combustion is 950-1100°C. Remove the attached water and crystal water of aluminum hydroxide to produce alumina that meets the requirements of electrolysis and other uses. Due to the high-temperature roasting process, although the flue gas temperature after combustion is only 950-11...

AI Technical Summary

Problems solved by technology

[0003] Since the NOx emission of the roaster is much higher than the currently implemented "Aluminum Industry Pollutant Emission Standard" (GB25465-2010) (2013 revised version), the NOx is required to be 100mg / m 3 The following emission standards, the current main method to control NOx emissions is to perform selective catalytic reduction (SCR) or selective non-catalytic reduction (SNCR) on the flue gas after combustion for denitrification, but there are environmental problems caused by high cost and ammonia escape. Secondary pollution and other issues

At present, the application of low-nitrogen burners in domestic aluminum hydroxide roasters has not yet been carried out, and most of them are single-channel burners. Therefore, a low-nitrogen burner is urgently needed to solve the above problems and realize low-cost nitrogen oxide emission reduction in aluminum hydroxide roasters. Target

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