Gas premixing burner device
By introducing a primary premixing chamber and a swirl mixing section into the gas burner unit of the steel plant, the problem of insufficient mixing of combustible gas and combustion-supporting gas is solved by utilizing the Venturi effect and the principle of swirl mixing. This improves combustion efficiency and temperature, and ensures the stability of steelmaking production and product quality.
Patent Information
- Application Number
- CN202520877385.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-06
- Publication Date
- 2026-02-13
- Estimated Expiration
- 2035-05-06
AI Technical Summary
In the baking facilities of steel plants, the gas burners lack premixing function, which leads to the inability of combustible gas and combustion-supporting gas to mix fully, resulting in low calorific value, high energy consumption, and affecting the quality of molten steel and billets, and even causing internal quality defects.
A gas premixed burner device was designed, comprising a primary premixing chamber, a swirling mixing section, and a mixing storage chamber. Utilizing the Venturi effect and the swirling mixing principle, it achieves efficient mixing of combustible gas and combustion-supporting gas. A negative pressure zone is formed through the built-in nozzle, contraction section, throat, and expansion section to naturally draw in combustion-supporting gas, and turbulent mixing is enhanced in the swirling mixing section.
It achieves thorough mixing of combustible gas and combustion-supporting gas, improves combustion efficiency and temperature, reduces energy consumption, ensures uniform baking temperature, and improves the quality of molten steel and billets.
Smart Images
Figure CN223909520U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to the burner device provided for the steelmaking plant area especially relates to a coal gas premixing burner device. BACKGROUND
[0002] In the production process of the steelmaking plant, various baking facilities such as iron ladle roaster, steel ladle roaster and tundish roaster all need to bake refractory through the burner.
[0003] However, the original steelmaking plant production area coal gas burner lacks premixing function, and when baking iron tank, steel tank and tundish, the combustible gas and combustion-supporting gas cannot be fully premixed, resulting in low gas combustion heat value and high energy consumption. Especially in the baking process of the steel ladle and the tundish, if the baking temperature is insufficient or uneven, it will not only seriously affect the quality of the molten steel and the billet, but also may cause internal quality defects of the billet. SUMMARY
[0004] The utility model provides a coal gas premixing burner device in view of the defects of prior art.
[0005] To achieve the above-mentioned purpose, the utility model adopts the following technical scheme, the coal gas premixing burner device includes the body, the cavity is communicated and is set up in the body, the cavity forms primary premixing bin, secondary premixing bin, rotational flow mixing section and mixed storage bin along the gas flow direction in proper order.
[0006] Among them, the primary premixing bin includes initial section, contraction section, throat and expansion section connected in proper order, the built-in nozzle is arranged in the initial section, one end of the built-in nozzle is communicated with the combustible gas channel, the other end of the built-in nozzle extends to the throat, and is used for high-speed injection of the combustible gas to the throat to form jet flow, the initial section is communicated with the combustion-supporting gas channel and forms a negative pressure zone at the throat, and the expansion section is communicated with the secondary premixing bin.
[0007] The spiral channel is arranged in the rotational flow mixing section, the inlet of the spiral channel is communicated with the secondary premixing bin, and the outlet of the spiral channel is communicated with the initial end of the mixed storage bin.
[0008] The terminal end of the mixed storage bin is connected with the initial end of the equalizing pressure pipe, and the terminal end of the equalizing pressure pipe is connected with the burner.
[0009] Further, the injection direction of the built-in nozzle is coaxially arranged with the central axis of the throat to maximize the effect of inducing combustion-supporting gas.
[0010] Further, the cross-sectional size of the initial section is greater than that of the contraction section, so as to provide sufficient flow space for the combustion-supporting gas.
[0011] Further, the throat forms a negative pressure area through the Venturi effect, so that the combustion-supporting gas is naturally sucked from the combustion-supporting gas channel; no additional power device is needed.
[0012] Further, the expansion section is a tapered pipe with gradually increasing cross-sectional area, i.e., the inlet is narrow and the outlet is wide; the cross-sectional area of the inlet is the same as that of the throat, and the cross-sectional area of the outlet matches that of the inlet of the second-stage premixing chamber; the expansion section is used to make the mixed gas sufficiently decelerate and pressurize in the expansion section, so as to realize the conversion of kinetic energy into pressure energy.
[0013] Further, the angle between the side wall of the expansion section and the central axis is θ, and 5°≤θ≤15°.
[0014] Further, the pipe diameter of the pressure equalization and pressurization pipe is 1 / 3-1 / 2 of the pipe diameter of the mixed storage chamber, so as to improve the ejection pressure of the mixed gas.
[0015] Further, adjustable valves are arranged on the combustible gas channel and the combustion-supporting gas channel respectively, so as to control the mixing ratio of the combustible gas and the combustion-supporting gas.
[0016] Further, the outlet of the burner adopts a circular or flat slit-shaped nozzle.
[0017] Compared with the prior art, the burner has the following beneficial effects.
[0018] The burner device for premixing gas increases a first-stage premixing chamber at the inlet, the first-stage premixing chamber adopts the Venturi effect: a negative pressure is formed through a contraction-expansion pipe to suck in air and mix with the gas, so that the mixing efficiency can reach more than 90%. The combustion-supporting gas and the combustible gas can be fully mixed, so that the combustion efficiency of the combustible gas is improved. When the combustible gas and the combustion-supporting gas are completely combusted, a higher combustion temperature can be obtained; the heat released by the complete combustion of the combustible gas per unit volume is improved.
[0019] The burner device for premixing gas increases a rotational flow mixing section at the middle part, adopts the rotational flow mixing principle: a spiral channel is arranged in the mixing cavity to make the entering gas produce turbulent flow and enhance the mixing. BRIEF DESCRIPTION OF DRAWINGS
[0020] The present application will be further described below in combination with the drawings and specific embodiments. The protection scope of the present application is not limited to the following content.
[0021] Figure 1 is a sectional view of the burner device for premixing gas.
[0022] In the figure, 1, combustible gas passage; 2, combustion-supporting gas pipeline; 3, first-stage premixing bin; 301, converging section; 302, throat; 303, diverging section; 304, built-in nozzle; 305, negative pressure zone; 306, initial section; 4, second-stage premixing bin; 5, rotational flow mixing section; 501, spiral passage; 6, mixing storage bin; 7, pressure-equalizing pressurizing pipe; 8, burner. DETAILED DESCRIPTION
[0023] In order to better understand the technical scheme of the present application, the following specific implementation is provided.
[0024] In the description of the present application, the description of the terms "one embodiment", "some embodiments", "exemplary embodiment", "preferred embodiment", "detailed description", or "preferred implementation" means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present application, the exemplary description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.
[0025] As shown in Figure 1 The coal gas premixing burner device includes a body, a communicating cavity is formed in the body, and the cavity sequentially forms a first-stage premixing bin 3, a second-stage premixing bin 4, a rotational flow mixing section 5 and a mixing storage bin 6 along the gas flow direction. The first-stage premixing bin 3 includes an initial section 306, a converging section 301, a throat 302 and a diverging section 303 connected in sequence, and the initial section 306 is provided with a built-in nozzle 304, one end of the built-in nozzle 304 is communicated with the combustible gas passage 1, the other end of the built-in nozzle 304 extends to the throat 302, and is used for high-speed injection of the combustible gas to the throat 302 to form a jet flow; the initial section 306 is communicated with the combustion-supporting gas passage 2 and forms a negative pressure zone 305 at the throat 302, and the diverging section 303 is communicated with the second-stage premixing bin 4. The throat 302 forms the negative pressure zone 305 through the Venturi effect, so that the combustion-supporting gas is naturally sucked from the combustion-supporting gas passage 2. No additional power device is needed.
[0026] The rotational flow mixing section 5 is provided with a spiral passage 501, an inlet of the spiral passage 501 is communicated with the second-stage premixing bin 4, and an outlet of the spiral passage 501 is communicated with a beginning end of the mixing storage bin 6. Specifically, the spiral passage 501 is arranged to make the mixed gas produce rotational flow, and realize the secondary mixing effect of migration of heavy components to the outer wall and aggregation of light components to the center under the action of centrifugal force. A terminal end of the mixing storage bin 6 is connected with a beginning end of a pressure-equalizing pressurizing pipe 7, and a terminal end of the pressure-equalizing pressurizing pipe 7 is connected with a burner 8. Moreover, an outlet of the burner 8 adopts a circular or flat slit-shaped nozzle.
[0027] Working principle and working process introduction:
[0028] One, the primary premixing bin adopts a Venturi effect premixing process, which is composed of an internal nozzle, a contraction section, a throat, and an expansion section. In the process, the combustible gas enters from the combustible gas channel and is sprayed out from the internal nozzle to form a high-speed jet flow, which induces the surrounding air to form a local low-pressure area (Bernoulli effect), i.e., a negative pressure area. At the same time, the negative pressure area is connected to the combustion-supporting gas pipeline. Due to the negative pressure at the throat, air is naturally sucked in through the combustion-supporting gas pipeline without the need for a fan to forcibly supply air. The air flow is determined by the cross-sectional area of the throat and the dynamic pressure of the gas jet (proportional adjustment can be achieved by a gas valve). The combustible gas and air collide at high speed at the throat, and the shearing action generates strong turbulence. The mixed gas is decelerated and pressurized in the expansion section, converting kinetic energy into pressure energy, and at the same time, the residence time is extended to promote uniform mixing. Then the mixed gas is further mixed in the secondary premixing bin, and then enters the spiral channel of the rotational mixing section.
[0029] Two, the rotational mixing section is provided with a spiral channel:
[0030] 1. The mixed gas is injected from one end of the spiral channel, directly forming a rotational flow (more easily generating strong turbulence).
[0031] 2. Under the action of centrifugal force, the heavy component (such as gas) migrates to the outer wall, and the light component (such as air) gathers to the center, forming a radial concentration gradient. This allows the mixed gas to form a secondary strong mixing.
[0032] 3. The end of the spiral channel is provided with a mixing storage bin to reduce the rotational flow intensity. The mixed gas enters the mixing storage bin, and then enters the fine-diameter pressure equalization pipe and is sprayed out from the burner.
[0033] In the preferred embodiment of the device, the jet direction of the internal nozzle 304 is coaxially arranged with the central axis of the throat 302 to maximize the induction capacity of the combustion-supporting gas. This design effectively utilizes the Bernoulli effect generated by the high-speed combustible gas flow to form a stable negative pressure area 305 at the throat, thereby achieving the natural suction of the combustion-supporting gas from the combustion-supporting gas channel 2 without the need for additional power equipment such as a fan, reducing energy consumption and improving system stability. The initial section 306 has a larger cross-sectional size than the contraction section 301, providing more flow space for the combustion-supporting gas and further enhancing the suction capacity and initial mixing effect of the gas flow. The expansion section 303 adopts a tapered structure with a narrow inlet and a wide outlet, with the inlet cross-sectional area consistent with the throat, and the outlet matched with the secondary premixing bin 4, allowing the mixed gas to be fully decelerated and pressurized in this section, efficiently converting kinetic energy into pressure energy, and at the same time, extending the gas residence time, which is conducive to achieving more uniform primary premixing. In addition, the angle θ between the expansion section side wall and the central axis is controlled between 5° and 15°, taking into account the requirements of smooth transition of gas flow and compactness of structure.
[0034] To further improve the mixing uniformity and adapt to different working conditions, the pipe diameter of the pressure equalizing and pressurizing pipe 7 is set to be between 1 / 3 and 1 / 2 of the pipe diameter of the mixing storage bin 6, so as to increase the ejection speed and momentum of the mixed gas by reducing the flow cross-sectional area, thereby helping to enhance the flame stiffness and combustion stability. Meanwhile, adjustable valves are arranged on the combustible gas channel 1 and the combustion-supporting gas channel 2 respectively, allowing the operator to flexibly adjust the ratio of the two kinds of gas according to the actual combustion demand, so as to realize accurate control of the air-fuel ratio and meet the combustion demand under various fuel types and load conditions. In addition, the spiral channel 501 in the rotational flow mixing section 5 not only strengthens the airflow disturbance, but also promotes the heavy components (such as fuel gas) to migrate to the wall surface and the light components (such as air) to gather in the center, forming a radial concentration gradient and further improving the secondary mixing strength, thereby laying a good foundation for subsequent stable combustion. Finally, the outlet of the burner 8 is designed as a circular or flat slit-shaped nozzle, which can select a suitable flame shape according to the application scene, thereby improving the application range and thermal efficiency performance of the burner.
[0035] The above examples are only used to illustrate the technical solutions of the present application, but not to limit them; although the present application has been described in detail with reference to the foregoing examples, those skilled in the art should understand that the technical solutions recorded in the foregoing examples can be modified, or some or all of the technical features can be replaced by equivalents; therefore, these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope defined by the claims of the present application.
Claims
1. A coal gas premix burner apparatus, characterized by: The body is provided with a cavity in communication, which forms a first premixing chamber (3), a second premixing chamber (4), a rotational flow mixing section (5) and a mixing storage chamber (6) in sequence along the gas flow direction; The first premixing chamber (3) comprises an initial section (306), a contraction section (301), a throat (302) and an expansion section (303) connected in sequence, the initial section (306) is provided with an internal nozzle (304), one end of the internal nozzle (304) is in communication with the combustible gas channel (1), the other end of the internal nozzle (304) extends to the throat (302) for high-speed injection of the combustible gas to the throat (302) to form a jet flow; the initial section (306) is in communication with the combustion-supporting gas channel (2) and forms a negative pressure area (305) at the throat (302), and the expansion section (303) is in communication with the second premixing chamber (4); The rotational flow mixing section (5) is provided with a spiral channel (501), the inlet of the spiral channel (501) is in communication with the second premixing chamber (4), and the outlet of the spiral channel (501) is in communication with the initial end of the mixing storage chamber (6); The terminal end of the mixing storage chamber (6) is connected with the initial end of the pressure equalizing and pressurizing pipe (7), and the terminal end of the pressure equalizing and pressurizing pipe (7) is connected with the burner (8).
2. A coal gas premix burner device according to claim 1, characterised in that: The injection direction of the internal nozzle (304) is coaxially arranged with the central axis of the throat (302) to maximize the effect of inducing the combustion-supporting gas.
3. A coal gas premix burner device according to claim 1, characterized in that: The cross-sectional size of the initial section (306) is larger than that of the contraction section (301), so as to provide sufficient flow space for the combustion-supporting gas.
4. The coal gas premix burner device according to claim 1, characterized in that: The throat (302) forms the negative pressure area (305) through the Venturi effect, so that the combustion-supporting gas is naturally sucked from the combustion-supporting gas channel (2).
5. The coal gas premix burner device according to claim 1, characterized in that: The expansion section (303) is a tapered pipe with gradually increasing cross-sectional area, the inlet cross-sectional area of the expansion section (303) is the same as the cross-sectional area of the throat (302), and the outlet cross-sectional area of the expansion section (303) matches the inlet cross-sectional area of the second premixing chamber (4); the expansion section (303) is used for making the mixed gas sufficiently slow down and pressurize in the expansion section (303) to realize the conversion of kinetic energy into pressure energy.
6. The coal gas premixing burner device according to claim 5, the angle between the side wall of the expansion section and the central axis is θ, and 5°≤θ≤15°.
7. The coal gas premix burner device according to claim 1, characterized in that: The pipe diameter of the pressure equalizing and pressurizing pipe (7) is 1 / 3-1 / 2 of the pipe diameter of the mixing storage chamber (6), so as to improve the ejection pressure of the mixed gas.
8. The coal gas premix burner device according to claim 1, characterized in that: Adjustable valves are arranged on the combustible gas channel (1) and the combustion-supporting gas channel (2) respectively, for controlling the mixing ratio of the combustible gas and the combustion-supporting gas.
9. The coal gas premix burner device according to claim 1, characterized in that: The outlet of the burner (8) adopts a circular or flat slit-shaped nozzle.