A gas burner for a pelletizing rotary kiln and a method of using the same

Abstract

The present application relates to a kind of pellet rotary kiln gas burner and its using method, and the gas burner includes premixing chamber, combustion air chamber, isolation air chamber and reinforcing air chamber arranged coaxially in order from inside to outside;Premixing chamber is equipped with gas inlet, premixing air inlet and premixed gas outlet;Combustion air chamber is equipped with combustion air inlet and combustion air outlet, isolation air chamber is equipped with isolation air inlet and isolation air outlet, reinforcing air chamber is equipped with isolation air inlet and isolation air outlet.Introduce isolation air (inert gas) in the gas burner, form dynamic isolation channel in the periphery of premixed gas, increase the moving distance of gas in dynamic isolation channel by reinforcing air (oxygen-rich gas), and realize secondary reinforcing combustion at the end of isolation air, to improve the appearance of rotary kiln gas combustion flame, effectively lengthen flame length, and make flame concentrated combustion, to achieve the purpose of optimizing pellet roasting process condition, saving fuel consumption.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of pellet rotary kiln, and particularly relates to a pellet rotary kiln gas burner and a use method thereof. BACKGROUND

[0002] The gas burner is an important component of the rotary kiln, and the performance of the gas burner directly affects the operation of the combustion equipment, and further affects the product quality, energy consumption and economic benefits of the steel enterprise.

[0003] In the rotary kiln pellet production of iron-making process, the combustor sprays the combustible and air to fully burn and provide heat energy, and then provides heat for the pellet roasting in the rotary kiln through radiation, convection and other heat exchange modes. The combustible used is divided into solid combustible (such as coal powder, biomass powder, etc.), gaseous combustible (such as coke oven gas, natural gas, etc.) and liquid combustible (such as heavy oil, etc.). The solid combustible is transported by gas-solid two-phase flow, and the gaseous combustible and the liquid combustible are transported by pressurization. Based on the inherent characteristics of the material, the gaseous combustible such as coal gas has some unfavorable factors in the combustion process in the rotary kiln, such as short flame length and scattered heat after combustion.

[0004] The Chinese utility model patent with the authorized announcement number CN206522771U discloses a "rotary kiln burner", which aims to provide a rotary kiln burner with strong flame adjusting capacity. The rotary kiln burner comprises a gas pipe assembly and a nozzle. The gas pipe assembly comprises six nested gas pipes, and the nozzle comprises six nested nozzle pipes. The six nozzle pipes are respectively arranged and connected with the six gas pipes to form six burner pipes. The innermost burner pipe and the spaces between the burner pipes form six gas passages. The six gas passages are the pilot gas passage, the center air duct, the first gas duct, the second gas duct, the cyclone air duct and the straight-flow air duct from inside to outside. The flame adjusting mode is more diversified, the long flame can be adjusted to be longer, the short flame can be adjusted to be shorter, and the thickness, angle and quadrant of the flame can be adjusted freely.

[0005] The patent for utility model with publication No. CN212581984U discloses "a belt type pellet induration machine induration system of energy saving and emission reduction", which includes induration burner, flue gas circulation pipeline, flue gas circulation fan, exhaust gas pipeline, exhaust gas fan and chimney. The induration section of the belt type pellet induration machine is provided with a plurality of induration burners, the induration burner is a two-section burner, and the burner is provided with a gas fuel inlet, a primary combustion-supporting gas inlet and a secondary combustion-supporting gas inlet. The flue gas outlet of the belt type pellet induration machine is connected with the flue gas circulation pipeline and the exhaust gas pipeline through the flue gas outlet pipeline, the flue gas circulation pipeline is connected with the primary combustion-supporting gas inlet and the secondary combustion-supporting gas inlet of the induration burner, and the flue gas circulation pipeline is provided with a flue gas circulation fan. The exhaust gas pipeline is connected with the chimney, and the exhaust gas pipeline is provided with an exhaust gas fan. The patent realizes low-oxygen combustion at the induration burner through the recycling of the flue gas discharged by the belt type pellet induration machine, and effectively reduces the emission of NOx in the pellet production process.

[0006] The patent for utility model with publication No. CN212778604U discloses "a combustion system of a belt type induration machine", which includes combustion furnaces arranged on both sides of the pallet along the running direction of the pallet, combustion chambers arranged in the combustion furnaces, smoke hoods connected with the upper parts of the pallets at the outlets of the combustion chambers, burners arranged on the side walls of the combustion furnaces to provide fuel, and secondary air pipes arranged at the top parts of the combustion furnaces. The burners and the secondary air pipes are in communication with the combustion chambers. The patent generates fuel in the burners by using low-calorific-value fuel, fully mixes the fuel with the gas in the secondary air pipes to generate high-temperature gas, preheats and indurates the green pellets, meets the requirements of the belt type pellet induration, avoids the consumption of high-calorific-value fuel gas, reduces the production cost, and simultaneously, the whole system has a simple structure and is easy to operate.

[0007] In the above prior art, the gas burners used in the iron-making pellet rotary kiln mostly use primary air as ignition air and secondary air as combustion-supporting air to improve the combustion rate and increase the flame length. However, there is no effective method to solve the problems of poor flame shape, heat dispersion after combustion, and difficult long-distance transportation of the flame in the combustion process. Therefore, the present application provides a pellet rotary kiln gas burner and a using method thereof. By adding isolation air and strengthening air, the appearance of the rotary kiln gas combustion flame is improved, and the pellet induration process conditions are optimized to save fuel consumption. SUMMARY

[0008] The present application provides a pellet rotary kiln gas burner and a using method thereof. By introducing isolation air (inert gas) into the gas burner, a dynamic isolation curtain is formed around the premixed gas. By using strengthening air (oxygen-rich gas), the moving distance of the gas in the dynamic isolation curtain is increased, and secondary strengthening combustion is realized at the end of the isolation air. Thus, the appearance of the rotary kiln gas combustion flame is improved, the flame length is effectively lengthened, and the flame is concentrated. Therefore, the pellet induration process conditions are optimized, and the fuel consumption is saved.

[0009] To achieve the above object, the application adopts the following technical scheme:

[0010] A gas burner for a pellet rotary kiln comprises, from inside to outside, a premixing chamber, a combustion air chamber, an isolation air chamber and a reinforcing air chamber arranged coaxially; one end of the premixing chamber, the combustion air chamber, the isolation air chamber and the reinforcing air chamber is aligned, and the end is the air outlet end of the gas burner; the lengths of the reinforcing air chamber, the isolation air chamber, the combustion air chamber and the premixing chamber increase in turn; the premixing chamber is provided with a gas inlet at the other end opposite to the air outlet end; the premixing chamber, the combustion air chamber, the isolation air chamber and the reinforcing air chamber are respectively provided with a premixing air inlet, a combustion air inlet, an isolation air inlet and a reinforcing air inlet on the side surface of the end away from the air outlet end; at the air outlet end, the premixing chamber is provided with a premixing gas outlet, the combustion air chamber is provided with a plurality of combustion air outlets, the isolation air chamber is provided with a plurality of isolation air outlets, and the reinforcing air chamber is provided with a plurality of reinforcing air outlets.

[0011] Further, the premixing chamber is in a cylindrical structure; the combustion air chamber, the isolation air chamber and the reinforcing air chamber are all circular annular channels, and each layer of the circular annular channels is supported by a plurality of support columns arranged at intervals.

[0012] Further, the combustion air outlets and the reinforcing air outlets are all circular through holes.

[0013] Further, the plurality of combustion air outlets, the plurality of isolation air outlets and the plurality of reinforcing air outlets are all uniformly arranged along the circumference of the gas burner.

[0014] Further, the isolation air outlets are four-prism-cone holes with a small inner opening and a large outer opening, the four-prism-cone holes are long strip holes with a short axis in the radial direction and a long axis in the tangential direction, and the taper angle of the four-prism-cone holes is 5°-10°.

[0015] Further, a cyclone structure is arranged in the isolation air chamber on the inner side of the isolation air outlets, and the cyclone structure is composed of a plurality of cyclone vanes uniformly arranged along the circumference of the gas burner, and the inclination angle of the cyclone vanes is 65°-90°.

[0016] Further, the gas burner for the pellet rotary kiln is made of high-temperature-resistant ceramic or high-temperature-resistant steel with a heat-resistant temperature not lower than 1300℃.

[0017] A use method of a gas burner for a pellet rotary kiln, comprising:

[0018] 1) premixing and ignition; introducing the gas into the premixing chamber through the gas inlet, introducing the combustion air into the premixing chamber through the premixing air inlet, fully mixing the gas and the combustion air in the premixing chamber, and igniting to form a flame at the air outlet end of the burner;

[0019] 2) increasing the premixing gas flow, and introducing high-temperature air into the combustion air chamber through the combustion air inlet to increase the flame propagation speed;

[0020] 3) After the combustion is stable, inert gas is introduced into the isolation air chamber from the isolation air inlet, the inert gas increases the flow rate through the cyclone structure, and after being sprayed out from the isolation air outlet, a dynamic isolation curtain is formed around the premixed gas, so that the flame is concentrated and the flame is lengthened;

[0021] 4) High-temperature oxygen-enriched air is introduced into the strengthening air chamber through the strengthening air inlet, and after the high-temperature oxygen-enriched air flows out from the strengthening air outlet, it meets the premixed gas at the end of the dynamic isolation curtain and performs secondary strengthening combustion.

[0022] Further, the inert gas is nitrogen, argon or carbon dioxide.

[0023] Further, the high-temperature air introduced into the strengthening air chamber from the strengthening air inlet is high-temperature oxygen-enriched air, and the oxygen enrichment rate satisfies the following formula:

[0024]

[0025] In the formula: η - oxygen enrichment rate of strengthening air, %

[0026] Q 隔 - Isolation air flow, m 3 ·h -1 ;

[0027] Q 加 - Strengthening air flow, m 3 ·h -1 .

[0028] Compared with the prior art, the beneficial effects of the present application are:

[0029] By introducing isolation air (inert gas) into the gas burner to form a dynamic isolation curtain around the premixed gas, and by introducing strengthening air (oxygen-enriched gas) to increase the moving distance of the gas in the dynamic isolation curtain, and by realizing secondary strengthening combustion at the end of the isolation air, the appearance of the rotary kiln gas combustion flame is improved, the flame length is effectively lengthened, and the flame is concentrated, thereby achieving the purpose of optimizing the pellet induration process conditions and saving fuel consumption. BRIEF DESCRIPTION OF DRAWINGS

[0030] The accompanying drawings, which form a part of this application, are included to provide a further understanding of the application and are incorporated in and constitute a part of this specification. The illustrations are shown to explain the present application and should not be taken as an improper limitation to the present application. In the drawings:

[0031] Figure 1 is a front view of a pellet rotary kiln gas burner according to the present application.

[0032] Figure 2 is a right view of Figure 1 .

[0033] Explanation of reference numerals in the attached figures:

[0034] In the diagram: 1. Premixing chamber 2. Combustion air chamber 3. Isolation air chamber 4. Reinforcement air chamber 5. Gas inlet 6. Premixed air inlet 7. Combustion air inlet 8. Isolation air inlet 9. Reinforcement air inlet 10. Flow structure 11. Premixed gas outlet 12. Combustion air outlet 13. Isolation air outlet 14. Reinforcement air outlet Detailed Implementation

[0035] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0036] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0037] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0038] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0039] like Figure 1 , Figure 2As shown, the gas burner for the pellet rotary kiln comprises, from inside to outside, a premixing chamber 1, a combustion air chamber 2, an isolation air chamber 3 and a reinforcing air chamber 4 arranged coaxially in sequence; one end of the premixing chamber 1, the combustion air chamber 2, the isolation air chamber 3 and the reinforcing air chamber 4 is aligned, and the end is the air outlet end of the gas burner; the lengths of the reinforcing air chamber 4, the isolation air chamber 3, the combustion air chamber 2 and the premixing chamber 1 increase in sequence; the premixing chamber 1 is provided with a gas inlet 5 at the other end opposite to the air outlet end; the premixing chamber 1, the combustion air chamber 2, the isolation air chamber 3 and the reinforcing air chamber 4 are respectively provided with a premixing air inlet 6, a combustion air inlet 7, an isolation air inlet 8 and a reinforcing air inlet 9 on the side surface away from the air outlet end; at the air outlet end, the premixing chamber 1 is provided with a premixing gas outlet 11, the combustion air chamber 2 is provided with a plurality of combustion air outlets 12, the isolation air chamber 3 is provided with a plurality of isolation air outlets 13, and the reinforcing air chamber 4 is provided with a plurality of reinforcing air outlets 14.

[0040] Further, the premixing chamber 1 is in a cylindrical structure; the combustion air chamber 2, the isolation air chamber 3 and the reinforcing air chamber 4 are all circular annular channels, and each layer of the circular annular channels is supported by a plurality of support columns arranged at intervals.

[0041] Further, the combustion air outlets 12 and the reinforcing air outlets 14 are all circular through holes.

[0042] Further, the plurality of combustion air outlets 12, the plurality of isolation air outlets 13 and the plurality of reinforcing air outlets 14 are all uniformly arranged along the circumference of the gas burner.

[0043] Further, the isolation air outlet 13 is a four-prism hole with a small inner opening and a large outer opening, the four-prism hole is a long strip hole with a short axis in the radial direction and a long axis in the tangential direction, and the taper angle of the four-prism hole is 5°-10°.

[0044] Further, the isolation air chamber 3 inside the isolation air outlet 13 is provided with a rotational flow structure 10, the rotational flow structure 10 is composed of a plurality of rotational flow plates uniformly arranged along the circumference of the gas burner, and the inclination angle of the rotational flow plate is 65°-90°.

[0045] Further, the gas burner for the pellet rotary kiln is made of high-temperature-resistant ceramic or heat-resistant steel with a heat-resistant temperature not less than 1300℃.

[0046] The use method of the gas burner for the pellet rotary kiln comprises the following steps:

[0047] 1) premixing and ignition; the gas is introduced into the premixing chamber 1 through the gas inlet 5, the combustion air is introduced into the premixing chamber 1 through the premixing air inlet 6, the gas and the combustion air are fully mixed in the premixing chamber, and the flame is ignited at the air outlet end of the burner;

[0048] 2) increasing the premixing gas flow, and introducing high-temperature air into the combustion air chamber 2 through the combustion air inlet 7 to increase the flame propagation speed;

[0049] 3) After the combustion is stable, inert gas is introduced into the isolation air chamber 3 from the isolation air inlet 8, the inert gas is improved in flow rate by the cyclone structure, and after being sprayed out from the isolation air outlet 13, a dynamic isolation curtain wall is formed around the premixed gas, so that the flame is concentrated and the flame is lengthened;

[0050] 4) High-temperature oxygen-enriched air is introduced into the reinforcing air chamber 4 through the reinforcing air inlet 9, and after the high-temperature oxygen-enriched air flows out from the reinforcing air outlet, it meets the premixed gas at the end of the dynamic isolation curtain wall and performs secondary strengthening combustion.

[0051] Further, the inert gas is nitrogen, argon or carbon dioxide.

[0052] Further, the high-temperature air introduced into the reinforcing air chamber from the reinforcing air inlet is high-temperature oxygen-enriched air, and the oxygen enrichment rate satisfies the following formula:

[0053]

[0054] In the formula: η - oxygen enrichment rate of reinforcing air, %

[0055] Q 隔 - Isolation air flow, m 3 ·h -1 ;

[0056] Q 加 - Reinforcing air flow, m 3 ·h -1 .

[0057] In the gas burner of the present application, the premixing chamber located at the center is of a cylindrical structure, the tail end is provided with a gas inlet, and the side close to the tail end is provided with a premixing air inlet for introducing pressurized gas (such as coal gas) and air for premixing; the outer side of the front section of the premixing chamber is a combustion-supporting air chamber, the tail end of the combustion-supporting air chamber is provided with a combustion-supporting air inlet for introducing combustion-supporting air; the outer side of the middle and front section of the combustion-supporting air chamber is an isolation air chamber, the tail end of the isolation air chamber is provided with an isolation air inlet for introducing isolation air; the outer side of the middle and front section of the isolation air chamber is a reinforcing air chamber, and the tail end of the reinforcing air chamber is provided with a reinforcing air inlet for introducing reinforcing air.

[0058] The premixing air inlet, the combustion-supporting air inlet, the isolation air inlet and the reinforcing air inlet are all inclinedly arranged, and the gas inflow end faces the air outlet end of the gas burner.

[0059] The combustion-supporting air chamber, the isolation air chamber and the reinforcing air chamber are all annular channel structures, and support columns are arranged between the annular channels.

[0060] The end face of the air outlet end of the gas burner is provided with a premixed gas outlet, a combustion air outlet, an isolating air outlet and a reinforcing air outlet; the combustion air outlet and the reinforcing air outlet are circular openings evenly distributed along the ring direction; the isolating air outlet is a long slot evenly distributed along the ring direction, and a rotating flow structure is arranged in the isolating air chamber on the inner side of the isolating air outlet.

[0061] All components of the gas burner for a pellet rotary kiln are made of high-temperature-resistant ceramic and heat-resistant steel, and the heat-resistant temperature is not less than 1300 DEG C.

[0062] To make the purpose, technical scheme and technical effect of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be described clearly and completely. However, the embodiments described below are only some of the embodiments of the present application, not all the embodiments. All other embodiments obtained by those skilled in the art without creative labor on the basis of the embodiments in the present application belong to the scope of protection of the present application.

[0063]

EMBODIMENT

[0064] In the embodiment, the gas burner for a pellet rotary kiln comprises, from inside to outside, a premixing chamber, a combustion air chamber, an isolating air chamber and a reinforcing air chamber arranged coaxially; one end of the premixing chamber, the combustion air chamber, the isolating air chamber and the reinforcing air chamber is aligned, and the end is the air outlet end of the gas burner; the lengths of the reinforcing air chamber, the isolating air chamber, the combustion air chamber and the premixing chamber increase in turn; the premixing chamber is provided with a gas inlet at the other end opposite to the air outlet end; the premixing chamber, the combustion air chamber, the isolating air chamber and the reinforcing air chamber are respectively provided with a premixing air inlet, a combustion air inlet, an isolating air inlet and a reinforcing air inlet on the side surface away from the air outlet end; at the air outlet end, the premixing chamber is provided with a premixed gas outlet, the combustion air chamber is provided with eight combustion air outlets, the isolating air chamber is provided with ten isolating air outlets, and the reinforcing air chamber is provided with sixteen reinforcing air outlets.

[0065] The premixing chamber has a cylindrical structure; the combustion air chamber, the isolating air chamber and the reinforcing air chamber are all circular annular passages, and each layer of circular annular passages is supported by a plurality of support columns arranged at intervals.

[0066] The plurality of combustion air outlets, the plurality of isolating air outlets and the plurality of reinforcing air outlets are evenly arranged along the circumference of the gas burner. The combustion air outlets and the reinforcing air outlets are both circular through holes. The isolating air outlets are four-pyramid holes with small inner openings and large outer openings, and the four-pyramid holes are long slot holes with a short axis in the radial direction and a long axis in the tangential direction. The taper angle of the four-pyramid hole is 6 DEG.

[0067] A rotating flow structure is arranged in the isolating air chamber on the inner side of the isolating air outlet, and the rotating flow structure is composed of 14 rotating flow vanes evenly arranged along the circumference of the gas burner. The inclination angle of the rotating flow vane is 75 DEG.

[0068] All components of the pellet rotary kiln gas burner in the embodiment are made of heat-resistant steel with a heat-resistant temperature of 1350 DEG C.

[0069] In the embodiment, the pellet rotary kiln gas burner is used as follows:

[0070] 1) premixing and ignition; introducing the gas into the premixing chamber through the gas inlet, introducing the combustion air into the premixing chamber through the premixing air inlet, fully mixing the gas and the combustion air in the premixing chamber, and igniting the flame at the air outlet end of the burner;

[0071] 2) increasing the premixing gas flow, and introducing the high-temperature air into the combustion air chamber through the combustion air inlet to increase the flame propagation speed;

[0072] 3) after the combustion is stable, introducing the inert gas into the isolation air chamber from the isolation air inlet, improving the flow rate of the inert gas through the cyclone structure, and spraying the inert gas from the isolation air outlet to form a dynamic isolation curtain around the premixing gas, so that the flame is concentrated and the flame is lengthened;

[0073] 4) introducing the high-temperature oxygen-enriched air into the strengthening air chamber through the strengthening air inlet, and the high-temperature oxygen-enriched air meets the premixing gas at the end of the dynamic isolation curtain after flowing out of the strengthening air outlet, and performs secondary strengthening combustion.

[0074] The gas is coal gas, and the inert gas is nitrogen.

[0075] Isolation air flow Q 隔 = 75 m 3 · h -1 ; the strengthening air flow Q 加 = 1100 m 3 · h -1 , and the oxygen enrichment rate of the strengthening air is 9%.

[0076] In the embodiment, the pellet rotary kiln gas burner is used to roast the pellets, the flame length is increased from 22 m when the conventional gas burner is used to 25 m, which is increased by 13.6%, and the flame shape is greatly improved, which provides a guarantee for high-quality pellet production in ironmaking.

[0077] The above is only a preferred specific embodiment of the present application, but the protection scope of the present application is not limited thereto, any person skilled in the art can make equivalent replacement or change according to the technical scheme and the inventive concept of the present application within the technical range disclosed by the present application, which should be covered in the protection scope of the present application.

Claims

1. A method of using a gas burner for a pelletizing rotary kiln, characterized in that, The pellet rotary kiln gas burner comprises, from inside to outside, a premixing chamber, a combustion air chamber, an isolation air chamber and a strengthening air chamber arranged coaxially; one end of the premixing chamber, the combustion air chamber, the isolation air chamber and the strengthening air chamber is aligned, and the end is the air outlet end of the gas burner; the lengths of the strengthening air chamber, the isolation air chamber, the combustion air chamber and the premixing chamber increase in turn; the premixing chamber is provided with a gas inlet at the other end opposite to the air outlet end; the premixing chamber, the combustion air chamber, the isolation air chamber and the strengthening air chamber are respectively provided with a premixing air inlet, a combustion air inlet, an isolation air inlet and a strengthening air inlet on the side away from the air outlet end; at the air outlet end, the premixing chamber is provided with a premixing gas outlet, the combustion air chamber is provided with a plurality of combustion air outlets, the isolation air chamber is provided with a plurality of isolation air outlets, and the strengthening air chamber is provided with a plurality of strengthening air outlets; the combustion air outlets and the strengthening air outlets are circular through holes; the plurality of combustion air outlets, the plurality of isolation air outlets and the plurality of strengthening air outlets are uniformly arranged along the circumference of the gas burner; the isolation air outlet is a four-pyramid hole with a small inner opening and a large outer opening, the four-pyramid hole is a long strip hole with a radial short axis and a tangential long axis, and the taper angle of the four-pyramid hole is 5-10°; a cyclone structure is arranged in the isolation air chamber on the inner side of the isolation air outlet, and the cyclone structure is composed of a plurality of cyclone vanes uniformly arranged along the circumference of the gas burner, and the inclination angle of the cyclone vanes is 65-90°. The use method of the pellet rotary kiln gas burner comprises: 1) premixing and ignition; the gas is introduced into the premixing chamber through the gas inlet, the combustion air is introduced into the premixing chamber through the premixing air inlet, the gas and the combustion air are fully mixed in the premixing chamber, and the flame is ignited at the air outlet end of the burner; 2) increasing the premixing gas flow, and introducing high-temperature air into the combustion air chamber through the combustion air inlet to increase the flame propagation speed; 3) after the combustion is stable, inert gas is introduced into the isolation air chamber from the isolation air inlet, the inert gas increases the flow rate through the cyclone structure, and an annular dynamic isolation curtain is formed around the premixing gas after the inert gas is sprayed out from the isolation air outlet, so that the flame is concentrated and the flame is lengthened; 4) high-temperature oxygen-enriched air is introduced into the strengthening air chamber through the strengthening air inlet, the high-temperature oxygen-enriched air meets the premixing gas at the end of the dynamic isolation curtain after flowing out from the strengthening air outlet, and secondary strengthening combustion is carried out; the oxygen enrichment rate of the high-temperature oxygen-enriched air satisfies the following formula: ； η = 21% / (21% + (100% - 21% ) * (1 - C) ) × 100% Q 隔 Isolated air flow, m 3 ·h -1 ; Q 加 — Reinforced air flow, m 3 ·h -1 .

2. A method of using a gas burner for a pellet rotary kiln according to claim 1, characterized in that, The premixing chamber is a cylindrical structure; the combustion air chamber, the isolation air chamber and the strengthening air chamber are all circular annular channels, and the circular annular channels are supported by a plurality of support columns arranged at intervals.

3. A method of using a gas burner for a pellet rotary kiln as claimed in claim 1, characterized in that, The high-temperature ceramic or heat-resistant steel has a heat-resistant temperature of not less than 1300 DEG C.

4. The method of using a gas burner for a balling rotary kiln according to claim 1, wherein, The inert gas is nitrogen, argon or carbon dioxide.

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