Diffusion burner

Abstract

The invention relates to a diffusion combustor, which belongs to the technical field of combustors and comprises a shell and a combustion chamber in the shell, a heating partition plate is arranged in the combustion chamber along the height and divides the interior of the combustion chamber into a left part and a right part which are completely independent, and the top of the heating partition plate extends out of the combustion chamber from an opening in the top of the combustion chamber. The combusted gas forms two sheet-shaped gas flows at the gas outlet; waste gas generated after combustion is brought out of a shell outside the combustion chamber through protective gas around the combustion chamber. And a glass window is arranged on the shell. And a porous medium is arranged in a cavity in the combustion chamber. Gas fuel and air are continuously heated through the heating partition plate, penetrate through the porous medium and flow along the heating partition plate to complete rectification, and mixed gas flow is formed at the gas outlet to be combusted. According to the invention, the research on the diffusion cross section of the fuel at the gas outlet, the research on the equivalence ratio of different types of fuels to air under different concentrations, and the research on the diffusion characteristics of oxynitride, soot and the like can be realized.

Description

Technical Field

[0001] The invention belongs to the technical field of burners, and in particular relates to a diffusion burner. Background Art

[0002] Diffusion burner is a burner designed according to the principle of diffusion combustion. In diffusion burner, fuel is sprayed into the furnace by gas nozzle, and combustion air is mixed with fuel and burned in the furnace. The characteristics of diffusion burner are stable combustion, no flashback problem, reliable operation, simple structure, and low-pressure fuel gas can be used, which has broad market prospects. In order to make the fuel gas and air mix better, the contact surface between the fuel gas and the air is increased as much as possible during the design of diffusion burner, so that the fuel gas and the air can be better mixed. Usually, in order to ensure that the air and the fuel gas are fully in contact, the air will be designed to pass through a porous medium structure before contacting the fuel gas. The burner with porous medium has three heat exchange modes of convection, heat conduction and radiation, so that the temperature of the combustion area tends to be uniform, so that a relatively stable temperature gradient can be maintained. In addition, there are non-premixed burners on the market.

[0003] Although the existing diffusion burner technology is relatively mature, it only ensures the quality of airflow to ensure sufficient combustion. However, the fuel diffusion is insufficient, and it is not easy to study the fuel outlet diffusion cross section, fuel-air mixing conditions, etc.

[0004] For example, a Chinese patent (publication number: CN202056874U, publication date: November 30, 2011) discloses a micro-sized diffusion burner, such as Figure 1 As shown, a fuel channel, an air channel and a combustion chamber are processed on the substrate, the outlet ends of the fuel channel and the air channel are connected to the inlet of the combustion chamber, the fuel channel, the air channel and the combustion chamber are arranged in a Y shape, and a porous medium is placed at the inlet of the combustion chamber. Although this technical solution sets up a micro combustion chamber, the fuel-air mixing is not sufficient, and it is impossible to accurately control the fuel-air mixing state.

[0005] A Chinese patent (publication number: CN221005056U, publication date: May 24, 2024) discloses a non-premixed diffusion burner, such as Figure 2As shown, it includes a shell of a cup-shaped structure, a glass bead layer is provided at the inner bottom of the shell, a porous metal medium layer is provided above the glass bead layer, a fuel hole is provided at the center of the bottom surface of the shell, the fuel hole is sealed with a fuel conduit, the fuel conduit passes through the glass bead layer and the porous metal medium layer in sequence, an air hole is provided on one side of the bottom surface of the shell, the air hole is sealed with an air conduit, the upper end of the air conduit is in contact with the glass bead layer; the upper port of the shell is provided with a detachable pressure ring, the inner cavity of the pressure ring is provided with a step, after the pressure ring is assembled with the shell, the bottom surface of the step is in contact with the upper port of the shell, and the bottom surface of the step is in contact with the upper surface of the porous metal medium layer. Although this technical solution adopts a non-premixed diffusion method, it is not easy to realize the research on the fuel diffusion cross section and the equivalent ratio of the gas. In addition, the softening of the glass beads will cause serious damage to the burner, block the airflow, and have a short service life. Summary of the invention

[0006] In view of the deficiencies in the prior art, the present invention provides a diffusion burner to solve the problem that the existing combustion chamber is not easy to study the diffusion cross section of the fuel and the equivalence ratio of different types of fuels to air at different concentrations, and the diffusion characteristics of nitrogen oxides, carbon soot, etc.

[0007] A diffusion burner comprises an outer shell and a combustion chamber inside the outer shell. A heating baffle is arranged along the height inside the combustion chamber to divide the inner part of the combustion chamber into two completely independent left and right parts. The top of the heating baffle extends out of the combustion chamber from an opening at the top of the combustion chamber. The post-combustion gas forms two sheet-like airflows at the gas outlet; the post-combustion exhaust gas is carried out of the outer shell outside the combustion chamber by the protective gas surrounding the combustion chamber.

[0008] The combustion chamber is a steel combustion chamber, the lower part of which is cylindrical and the upper part of which is truncated cone.

[0009] The top of the combustion chamber is provided with strip-shaped holes as gas outlets.

[0010] The heating baffle is in sheet shape, and the thickness of the heating baffle is smaller than the width of the opening.

[0011] A porous medium is arranged in the cavity inside the combustion chamber, dividing the interior of the combustion chamber into two parts, an upper part and an lower part.

[0012] A protective gas pipeline is arranged at the bottom of the shell, and a protective gas outlet is opened at the top of the shell.

[0013] The shell is provided with a glass observation window for observing the internal flame.

[0014] The beneficial effects of the present invention are as follows: the diffusion burner provided by the present invention uses a heating baffle to separate the gas fuel and the air, and the blown gas can quickly complete heating and rectification through the porous medium on both sides of the heating baffle. Due to the protruding design of the baffle at the gas outlet, a relatively obvious diffusion cross section will be formed on both sides, forming a counter-jet and igniting. The present invention provides a fuel-air diffusion combustion platform, which can accurately control the fuel-air mixing state and provide a sheet-like diffusion flame shape.

[0015] The present invention can realize the research on the diffusion cross section of the fuel at the gas outlet, the research on the equivalence ratio of different types of fuels to air at different concentrations, and the research on the diffusion characteristics of nitrogen oxides, carbon smoke, etc.

[0016] The invention has an intuitive structure, is easy to assemble, does not require complicated transmission coordination, and brings new technical inspiration to the design of diffusion burners. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A schematic diagram of a micro-diffusion burner in the prior art;

[0018] Figure 2 A schematic diagram of a non-premixed diffusion burner in the prior art;

[0019] Figure 3 A schematic diagram of a diffusion burner provided by the present invention;

[0020] Figure 4 It is a schematic diagram of the combustion chamber part of the present invention;

[0021] Figure 5 It is a front view of the combustion chamber part of the present invention;

[0022] Figure 6 A top view of the combustion chamber portion of the present invention;

[0023] Figure 7 is a schematic diagram of a housing in the present invention;

[0024] Figure 8 A bottom view of the housing of the present invention;

[0025] Figure 3-Figure 8 middle:

[0026] 1-heating baffle, 2-combustion chamber, 3-air duct, 4-fuel duct, 5-gas outlet, 6-housing, 7-porous medium, 8-gas fuel, 9-air, 10-glass observation window, 11-protective gas duct, 12-protective gas outlet. DETAILED DESCRIPTION

[0027] In order to better explain the present invention and facilitate understanding, the technical solutions and effects of the present invention are described in detail below through specific implementation modes in conjunction with the accompanying drawings.

[0028] like Figure 3-Figure 8 As shown, a diffusion burner comprises a shell 6 and a cylindrical combustion chamber 2 arranged in the shell 6, wherein the combustion chamber 2 is a steel shell, and in this embodiment, 304 steel is used, the lower part is cylindrical, and the upper part is truncated cone-shaped. An opening is provided at the top of the combustion chamber 2, which is in the shape of a strip and serves as a gas outlet 5. A porous medium 7 is provided in the cavity inside the combustion chamber 2, dividing the interior of the combustion chamber 2 into two parts, an upper part and an lower part. The porous medium 7 can be a catalyst, such as a composite catalyst formed by microfiber-type sintered nickel (Ni) encapsulated on the outside of platinum / alumina (Pt / Al2O3) fine particles, or a non-catalyst, such as nickel powder fired at 700 degrees. A heating baffle 1 is provided inside the combustion chamber 2 along the height direction, dividing the interior of the combustion chamber 2 into two completely independent left and right parts; the bottom of the heating baffle 1 is fixed to the bottom of the combustion chamber 2, and the top of the heating baffle 1 extends from the opening at the top of the combustion chamber 2 to the outside of the combustion chamber 2. The heating baffle 1 is in sheet shape, and the thickness of the heating baffle 1 is less than the width of the opening, so that the gas after combustion forms two sheet-shaped airflows at the gas outlet 5, slowing down the time of intersection, which is used to observe the flame shape. The heating baffle 1 in this embodiment is a micro heating plate. An air duct 3 and a fuel duct 4 are provided at the bottom of the combustion chamber 2, respectively arranged in the left and right parts of the combustion chamber 2, for respectively introducing air 9 and gas fuel 8 into the combustion chamber 2. The gas fuel 8 and air 9 are continuously heated by the heating baffle 1, pass through the porous medium 7, flow along the heating baffle 1 to complete rectification, and form a mixed airflow at the gas outlet 5 for combustion. The exhaust gas after combustion is taken out by nitrogen. In addition, nitrogen is also used as a protective gas to prevent flashback.

[0029] The combustion chamber 2 is provided with a shell 6 outside, a protective gas pipeline 11 is provided at the bottom of the shell 6, and is used to pass protective gas between the shell 6 and the combustion chamber 2, and a protective gas outlet 12 is provided at the top of the shell 6, and the protective gas carries the exhaust gas after combustion out of the shell 6. The shell 6 is provided with a glass observation window 10 for observing the flame inside.

[0030] When in use, firstly, protective gas is introduced into the shell 6 through the protective gas pipeline 11, that is, nitrogen is introduced around the burner as protective gas. Then, heating is performed by using the heating baffle 1 to heat the cavity in advance and continuously heat it. The heating baffle 1 is used as a heat source to heat the air 9 blown in from the air pipeline 3 and the gas fuel 8 blown in from the fuel pipeline 4 to achieve the energy required for ignition. With the introduction of air 9 and gas fuel 8, the porous medium 7 and the heating baffle 1 rectify the gas: the heated gas on both sides of the heating baffle 1 flows along the heating baffle 1 through the porous medium 7 to complete the rectification, and finally is ejected and ignited at the gas outlet 5, and the flame can be observed through the glass observation window 10 of the shell 6.

Claims

1. A diffusion burner, characterized in that: It includes an outer shell and a combustion chamber inside the outer shell. A heating partition is arranged along the height inside the combustion chamber to divide the inner part of the combustion chamber into two completely independent left and right parts. The top of the heating partition extends out of the combustion chamber from an opening at the top of the combustion chamber. The post-combustion gas forms two sheet-like airflows at the gas outlet; the post-combustion exhaust gas is carried out of the outer shell outside the combustion chamber by the protective gas surrounding the combustion chamber.

2. A diffusion burner according to claim 1, characterized in that: The combustion chamber is a steel combustion chamber, the lower part of which is cylindrical and the upper part of which is truncated cone.

3. A diffusion burner according to claim 1, characterized in that: The top of the combustion chamber is provided with strip-shaped holes as gas outlets.

4. A diffusion burner according to claim 3, characterized in that: The heating baffle is in sheet shape, and the thickness of the heating baffle is smaller than the width of the opening.

5. A diffusion burner according to claim 1, characterized in that: A porous medium is arranged in the cavity inside the combustion chamber, dividing the interior of the combustion chamber into two parts, an upper part and an lower part.

6. A diffusion burner according to claim 1, characterized in that: A protective gas pipeline is arranged at the bottom of the shell, and a protective gas outlet is opened at the top of the shell.

7. A diffusion burner according to claim 6, characterized in that: The shell is provided with a glass observation window for observing the internal flame.

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