Double-regenerative combustor

Abstract

The invention discloses a double-regenerative combustor, which comprises a blast furnace gas burner and a combustion-supporting air burner which are embedded on the furnace wall in pair. The blast furnace gas burner and the combustion-supporting air burner comprises a blast furnace gas burner block and a combustion-supporting air burner block respectively, one end, leading to a furnace, of the blast furnace gas burner block is provided with gas burner nozzles, one end, leading to the furnace, of the combustion-supporting air burner block is provided with air burner nozzles, and the spaying directions of the nozzles inwardly incline to one another and form an included angle of 2-15 degrees relative to the horizontal plane. A gas burner block hollow cavity is arranged at one end, facing the outer side of the furnace wall, of the blast furnace gas burner block, an air burner block hollow cavity is arranged at one end, facing the outer side of the furnace wall, of combustion-supporting air burner block, and a thick-walled honeycomb ceramic heat accumulator, a conventional honeycomb ceramic heat accumulator, a metal barrier and a pipe connecting box are arranged on each of the gas burner block hollow cavity and the air burner block hollow cavity from inside to outside. By the means, the purposes of effectively delaying damage process of the double-regenerative combustor, greatly prolonging the service lives of the burner blocks, and improving usability of the double-regenerative combustor and thermal property of the heating furnace are finally achieved.

Description

technical field [0001] The invention relates to an industrial furnace gas burner, in particular to a double regenerative burner. Background technique [0002] Regenerative combustion technology usually recovers waste heat from flue gas through regenerative heat storage, preheats the combustion medium to 800-1100°C, and at the same time realizes high-temperature oxygen-lean combustion through the jet flow of the combustion medium and cigarette smoke during the combustion process. It significantly reduces the NOx concentration in the combustion process, and has the technical characteristics of energy saving and environmental protection. Due to the high preheating temperature of the combustion medium, the physical heat brought in by the combustion medium is increased, so the use of low calorific value gas can also meet the heating needs of industrial furnaces. [0003] In domestic iron and steel enterprises, the fuel used in industrial furnaces is mainly the by-product gas of ...

AI Technical Summary

Problems solved by technology

The utility model with the patent number ZL03268896.2 discloses a circular regenerative burner, which aims at the uneven thermal expansion of the square casing of the conventional regenerative burner, poor thermal shock stability, serious cracks and peeling at the four corners, and a service life of about If one year is not enough, the thermal insulation lining and shell of the burner are designed as a cylindrical structure to alleviate the process of crack peeling and damage caused by the uneven thermal expansion of the conventional square shell regenerative burner. The service life of the burner thermal insulation lining and shell is expected to reach 3 years, about 3 times that of conventional square casing regenerative burners

The utility model with the patent number ZL01236401.9 discloses an energy-saving and environment-friendly double regenerative burner that can adapt to low calorific value blast furnace gas and low nitrogen oxides. The gas nozzle channel structure has the problems of high furnace temperature, high nitrogen oxides, and insignificant energy saving and environmental protection effects. Referring to the design principle of the flue gas in the Japanese FDI burner with multiple small nozzles and high-speed jet ejection in the furnace, through the center of the burner At least two pairs of combustion-supporting air channels are arranged symmetrically around the blast furnace gas channel. The nozzles of each pair of combustion-supporting air channels are not equal to the nozzles of the central blast furnace gas channel. 5~20°, it can delay the mixing of combustion air and blast furnace gas, and achieve the purpose of staged combustion; through the regenerator set at the entrance of the combustion air channel and the central blast furnace gas channel, the combustion air and blast furnace gas can be mixed double warm up

[0006] It can be seen that the domestic research on dual regenerative burners mainly focuses on the energy saving and environmental protection of gas combustion and the containment of burner damage, and does not involve the influence of the working conditions of the burner.

However, the double regenerative heating furnace is a wide and short high-yield heating furnace. In order to ensure the heating load of the heating furnace, the heat load of the double regenerative burner is high, resulting in a large size of the burner; at the same time, in order to save the layout of the burner space, which is convenient for burner layout and reduces the flow resistance of high-temperature double preheating combustion medium. The burner nozzle and burner brick generally adopt a square structure design to expand the nozzle flow area, reduce the surface area of ​​the furnace wall occupied by the burner brick, and thin the burner The wall thickness of the brick nozzle part expands the built-in space of the burner heat storage body

However, the structure of the large-sized square nozzle and the thinner wall thickness lead to a large structural stress of the nozzle, a decrease in structural stability and stress damage resistance, and at the same time, it also leads to the direct impact of high-temperature radiation in the furnace on the front heat storage body on the high-temperature side of the burner through the nozzle. Radiation heating aggravates the high-temperature deformation, ablation and damage of the front heat storage body, reduces the heat transfer performance of the heat storage body, and improves the flow resistance. Therefore, a high-temperature performance Excellent fire-blocking brick with large wall thickness, which can block the influence of radiation in the furnace on the honeycomb ceramic regenerator on the high temperature side

However, the setting of the fire brick occupies the built-in space of the burner's regenerator. In the case of limited layout space in the burner, in order to maintain the volume of the built-in regenerator, the wall thickness of the nozzle area of ​​the burner brick will inevitably be further reduced. Thin, which further reduces the damage resistance of the burner brick and the stability of the combustion characteristics of the burner

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