Outer ring airflow cooling heat storage burner

Abstract

The invention belongs to the technical field of combustors, and particularly discloses an outer ring airflow cooling heat storage burner which is provided with a burner body, a combustion cavity is formed in the first side of the burner body, and the first side of the combustion cavity communicates with a flame nozzle. The burner body is sequentially sleeved with an outer annular cooling gas cavity, an annular-column-shaped outer heat storage cavity and an annular-column-shaped inner heat storage cavity from outside to inside, the second side of the outer heat storage cavity is communicated with the second side of the inner heat storage cavity, the end of the first side of the inner heat storage cavity is communicated with the combustion cavity, and the burner body is further provided with a gas cavity and a mixing cavity. The outer ring cooling gas cavity and the fuel gas cavity are respectively communicated with the mixing cavity, and the first side end part of the mixing cavity is communicated with the combustion cavity; the device has the beneficial effects of small size, light weight, low raw material consumption, high waste heat utilization rate, high furnace temperature uniformity, low-oxidation and non-oxidation heating combustion and the like.

Description

Technical Field

[0001] The invention belongs to the technical field of burners, and in particular discloses an outer-ring air-flow cooling regenerative burner. Background Art

[0002] The high-temperature air regenerative combustion technology is widely used in the industrial thermal engineering field. By adopting this combustion technology, the thermal efficiency of furnace and kiln equipment can be increased by more than 50%, and the energy-saving effect is extremely remarkable.

[0003] The essence of regenerative combustion is self-preheating. Its basic principle is to configure multiple sets of burner devices in pairs on furnace and kiln equipment. These paired burners alternately perform combustion or smoke exhaust work periodically. When the burner is in the smoke exhaust cycle condition, the high-temperature flue gas in the furnace passes through the burner, exchanges heat with the heat storage medium in the burner device, displaces the heat in the flue gas, and the heat storage medium accumulates heat. When a cycle ends and the burner switches to the combustion cycle condition, the normal-temperature combustion-supporting air flows through the heat storage medium for heat exchange and can be preheated to a very high temperature to participate in combustion, thereby achieving the energy-saving goal.

[0004] In the prior art, for example, CN111664451A discloses a low-calorie gas burner with a regenerative flame-stabilizing cone. The outer end of the combustion-supporting air pipe is provided with a combustion-supporting air inlet, and the inner end is communicated with the regenerative mixing chamber; the other end of the regenerative mixing chamber is connected to the furnace chamber; the combustion-supporting air pipe, the gas pipe and the central air pipe are coaxially arranged from outside to inside. The outer end of the central air pipe extends outside the gas pipe to be the central combustion-supporting air inlet, and the inner end is located in the regenerative mixing chamber and is connected to the regenerative flame-stabilizing cone; the outer end of the gas pipe is provided with a gas inlet, and the inner end is located in the regenerative mixing chamber; in the regenerative mixing chamber, a swirler is arranged between the outer wall of the inner end of the gas pipe and the inner wall of the inner end of the combustion-supporting air pipe.

[0005] The above prior art has the following defects: 1. It is necessary to set a thick heat insulation layer; 2. The design of the flame-stabilizing cone requires materials with better heat resistance, and the service life during high-temperature operation is more affected by the selected materials; 3. The air flow velocity at the burner nozzle is relatively low, and the furnace temperature uniformity is poor; 4. Without the design of supplementary combustion air, the regulation of the furnace atmosphere is relatively poor. Summary of the Invention

[0006] In order to solve the above problems, the purpose of the present invention is to disclose an outer-ring air-flow cooling regenerative burner, which is realized by the following technical solutions.

[0007] An outer-ring air-flow cooling regenerative burner has a burner body. A combustion cavity is provided on the first side of the burner body, which can premix part of the gas and air. A cover is provided on the second side of the burner body. A combustion chamber is provided in the combustion cavity, which can achieve partial combustion to make the air flow expand at high temperature. A flame nozzle is communicated with the first side of the combustion chamber. The size and shape of the flame nozzle can change the shape and speed of the combustion air flow to meet the heating process requirements. The heat transferred from the inside of the burner is carried back into the combustion chamber by the normal-temperature supplementary combustion air and gas, eliminating the thick heat insulation layer on the outside. The burner body is successively sleeved with an outer ring cooling air chamber, an annular columnar outer heat storage chamber, and an annular columnar inner heat storage chamber from outside to inside. Heat storage bodies are arranged in the outer heat storage chamber and the inner heat storage chamber, and the second sides of the outer heat storage chamber and the inner heat storage chamber are connected; A main air inlet is provided on the burner body, and the main air inlet is communicated with the outer heat storage chamber. The first side end of the inner heat storage chamber is communicated with the combustion chamber; A gas chamber and a mixing chamber are also provided on the burner body. The gas chamber is located outside the mixing chamber. The outer ring cooling air chamber and the gas chamber are respectively communicated with the mixing chamber. The first side end of the mixing chamber is communicated with the combustion chamber; A supplementary combustion air inlet communicated with the outer ring cooling air chamber and a gas inlet communicated with the gas chamber are also provided on the burner body. The first side and the second side are two sides with opposite directions. For example, if the first side is the left side, the second side is the right side.

[0008] For the above-described outer ring air flow cooling regenerative burner, the first side end of the mixing chamber is communicated with the combustion chamber through a plurality of mixed gas nozzles.

[0009] For the above-described outer ring air flow cooling regenerative burner, all the mixed gas nozzles are distributed in an annular array.

[0010] For the above-described outer ring air flow cooling regenerative burner, the outer ring cooling air chamber is spiral.

[0011] For the above-described outer ring air flow cooling regenerative burner, an ignition nozzle pipe is sleeved inside the inner circle of the inner heat storage chamber. The first side end of the ignition nozzle pipe is communicated with the combustion chamber. The second side end of the ignition nozzle pipe passes through the cover, and an ignition component is also provided on the ignition nozzle pipe on the second side of the cover.

[0012] For the above-described outer ring air flow cooling regenerative burner, the ignition component is composed of an ignition electrode, an ignition gas inlet, and an ignition air inlet.

[0013] For the above-described outer ring air flow cooling regenerative burner, an observation mirror is provided at the second side end of the ignition nozzle pipe for observing the flame state in the combustion chamber.

[0014] For the above-described outer ring air flow cooling regenerative burner, the main air inlet is located above the first side of the burner body.

[0015] For the above-described outer ring air flow cooling regenerative burner, the gas inlet is located at the rear side of the burner body and on the first side of the main air inlet.

[0016] An external-ring air-flow cooling regenerative burner as described above, the supplementary combustion air inlet is located on the front side of the burner body and on the second side of the main air inlet.

[0017] The present application has the following beneficial effects: 1. Utilize the flow of supplementary combustion air and fuel gas to carry away heat, cool the burner housing, make full use of the cold fluids of supplementary combustion air and fuel gas, absorb the externally transferred temperature of the regenerator, make full use of the waste heat while reducing the housing temperature, with high waste heat utilization rate, reducing raw material consumption and saving costs; no longer need a thick housing heat insulation layer, the burner volume is reduced and the weight is light.

[0018] 2. The regenerator adopts an inner and outer concentric sleeve structure, effectively reducing the burner length and having higher space utilization rate.

[0019] 3. The fuel gas and supplementary combustion air are provided with independent channels and a mixing chamber, and after mixing, they are sprayed into the combustion chamber and then mixed with the main air for combustion. Utilize the internal combustion structure to make the combustion gas expand, with a high flame ejection speed, increasing the disturbance of the furnace atmosphere and improving the furnace temperature uniformity.

[0020] 4. By adjusting the ratio of supplementary combustion air to main air volume, when the excess air coefficient α < 1 in the combustion chamber 2, the fuel gas cannot be completely burned, and the temperature in the combustion chamber 2 can be controlled, significantly reducing the generation of NOx. The ejected flame gas can form a reducing atmosphere, enabling the workpieces in the furnace to be heated in a reducing atmosphere and meeting the use requirements of furnaces with reducing heating requirements.

[0021] 5. When the excess air coefficient α > 1 in the combustion chamber 2, the ejected flame gas can form an oxidizing atmosphere, enabling the workpieces in the furnace to be heated in an oxidizing atmosphere and meeting the use requirements of furnaces with oxidizing heating requirements. Description of the Drawings

[0022] Figure 1 It is a schematic internal structure diagram in the main view direction of an embodiment of the present invention.

[0023] Figure 2 It is an enlarged view of area A of an embodiment of the present invention.

[0024] Figure 3 It is a sectional view taken along B-B of an embodiment of the present invention.

[0025] Figure 4 It is a sectional view taken along A-A of an embodiment of the present invention.

[0026] Figure 5 It is a top view of an embodiment of the present invention.

[0027] Figure 6 It is a right view of an embodiment of the present invention.

[0028] Figure 7It is a schematic diagram of the outer ring cooling air cavity structure in the top view direction of an embodiment of the present invention.

[0029] Figure 8 It is a cross-sectional view taken along D-D of an embodiment of the present invention.

[0030] Figure 9 It is a cross-sectional view taken along C-C of an embodiment of the present invention.

[0031] Figure 10 It is a cross-sectional view in the front view direction after the embodiment of the present invention is installed in a furnace.

[0032] Figure 11 It is a top view after the embodiment of the present invention is installed in a furnace.

[0033] In the figure, the corresponding names of the reference numerals are as follows: 1. Flame nozzle, 2. Combustion chamber, 3. Mixed gas nozzle, 4. Fourth air hole, 5. Main air inlet, 6. Outer ring cooling air cavity, 7. Outer regenerative cavity, 8. Inner regenerative cavity, 9. Cover, 10. Ignition electrode, 11. First air hole, 12. Ignition nozzle pipe, 13. Second air hole, 14. Gas chamber, 15. Third air hole, 16. Mixing chamber, 17. Supplementary combustion air inlet, 18. Gas inlet, 19. Ignition gas inlet, 20. Ignition air inlet, 21. Observation mirror. Detailed implementation manners

[0034] Embodiment: As Figures 1 to 9 , an outer ring air flow cooling regenerative burner has a burner main body. A combustion cavity is provided on the first side of the burner main body, and a cover 9 is provided on the second side of the burner main body. A combustion chamber 2 is provided in the combustion cavity. A flame nozzle 1 is communicated with the first side of the combustion chamber 2; The burner main body is successively sleeved with an outer ring cooling air cavity 6, a cylindrical outer regenerative cavity 7, a cylindrical inner regenerative cavity 8 and an ignition nozzle pipe 12 from outside to inside. Regenerative bodies are provided in the outer regenerative cavity 7 and the inner regenerative cavity 8. The second side of the outer regenerative cavity 7 and the second side of the inner regenerative cavity 8 are communicated through a first air hole 11. The outer ring cooling air cavity 6 is spiral; A main air inlet 5 is provided above the first side of the burner main body. The main air inlet 5 is communicated with the first side of the outer regenerative cavity 7. The first side of the inner regenerative cavity 8 is communicated with the combustion chamber 2 through a plurality of fourth air holes 4. The first side end of the ignition nozzle pipe 12 is communicated with the combustion chamber 2. The second side end of the ignition nozzle pipe 12 passes through the cover 9. An observation mirror 21 is provided at the second side end of the ignition nozzle pipe 12 for observing the flame state in the combustion chamber 2. An ignition electrode 10, an ignition gas inlet 19 and an ignition air inlet 20 are further provided on the ignition nozzle pipe 12 on the second side of the cover 9; The burner body is also provided with a gas chamber 14 and a mixing chamber 16. The gas chamber 14 and the mixing chamber 16 are located on the first side of the outer ring cooling air chamber 6. The gas chamber 14 is located outside the mixing chamber 16. The outer ring cooling air chamber 6 communicates with the mixing chamber 16 through a second air hole 13, and the gas chamber 14 communicates with the mixing chamber 16 through a third air hole 15. A plurality of mixed gas nozzles 3 communicating with the combustion chamber 2 are provided at the first side end of the mixing chamber 16, and all the mixed gas nozzles 3 are distributed in a ring array; The burner body is also provided with a supplementary combustion air inlet 17 communicating with the outer ring cooling air chamber 6 and a gas inlet 18 communicating with the gas chamber 14. The gas inlet 18 is located at the rear side of the burner body and on the first side of the main air inlet 5. The supplementary combustion air inlet 17 is located at the front side of the burner body and on the second side of the main air inlet 5.

[0035] Such as Figure 10 and Figure 11 , the outer ring air flow cooling regenerative burners described in the present application are provided on the first side and the second side of the furnace in the same number respectively, and the combustion chamber body is fixed in the furnace: During the combustion operation: 1. The gas on the second side enters from the gas inlet 18, flows through the gas chamber 14 and then enters the mixing chamber 16, mixes with the supplementary combustion air and is sprayed into the combustion chamber 2 from the mixed gas nozzles 3.

[0036] 2. The main air inlet 5 is opened, and the main air inlet 5 is adjusted to a suitable flow rate according to the setting of the fuel gas volume. Generally, the main air flow rate is between 60% and 95% of the air requirement of a single burner, that is, the air excess coefficient α is between 0.6 and 0.95. Then it flows through the outer regenerative chamber 7, the inner regenerative chamber 8 and enters the combustion chamber 2 from the fourth air hole 4.

[0037] 3. The supplementary combustion air enters from the supplementary combustion air inlet 17. The supplementary combustion air volume is generally between 25% and 5% of the total air requirement of a single burner, that is, the air excess coefficient α is between 0.25 and 0.05. These supplementary combustion air, whether it is for the combustion on the second side or the exhaust gas on the first side, is always open. Example of the adjustment method of the supplementary combustion air volume: when the air entering from the main air inlet 5 is 60%, the flow rate entering at the supplementary combustion air inlet 17 is 25%. At this time, the combustion in the combustion chamber 2 is carried out with an oxygen deficiency of about 20%. The combustion under the condition of high preheated air can control the combustion temperature and also limit the generation of NOx.

[0038] 4. The supplementary combustion air entering the combustion chamber 2 mixes with the gas mixture of the gas and the main air, is ignited by the ignition nozzle 12 and burns. The volume of the combustion flame gas increases several times after combustion. By controlling the cross-sectional size of the designed nozzle 1, a medium-speed or even high-speed flame air flow can be obtained, which can disturb the air flow in the furnace and improve the furnace temperature uniformity. In this way, the flame gas sprayed into the furnace ensures an oxygen-free atmosphere.

[0039] When the ignition nozzle operates, ignition air enters the ignition nozzle tube 12 from the ignition air inlet 20, and ignition gas enters the ignition nozzle tube 12 from the ignition gas inlet 19. After being ignited by the ignition electrode 10, the flame sprays from the ignition nozzle tube 12 into the combustion chamber 2 to ignite the mixture. During the smoke exhaust operation: 1. The gas inlet 18 on the first side is closed, and the main air inlet 5 is opened and commutated to exhaust smoke.

[0040] 2. The flame gas is inhaled from the first-side flame nozzle 1. At this time, the inhaled flame gas with an oxygen deficiency of about 20% enters the combustion chamber 2.

[0041] 3. The flow rate entering at the first-side afterburning air inlet 17 is 25%. It flows through the outer ring cooling air chamber 6 and then enters the mixing chamber 16, and sprays into the combustion chamber 2 from the mixture nozzle 3.

[0042] 4. The flame gas with an oxygen deficiency of about 20% that has not been completely burned and the cooling air with a flow rate of 25% entering at the first-side afterburning air inlet 17 are further afterburned in the combustion chamber 2. At low temperatures, it is ignited and burned through the ignition nozzle 12, and at high temperatures, it is ignited by its own residual temperature, and no longer requires the ignition nozzle to ignite.

[0043] 5. The exhausted smoke flows through the inner heat storage chamber 8 and the outer heat storage chamber 7, so that the temperature of the smoke is reduced to 100 - 150 °C and then flows out from the main air inlet 5; After a predetermined time of commutation, the regenerative burner on the first side is used for combustion, and the regenerative burner on the second side is used for smoke exhaust; In this way, reciprocating commutation is carried out to achieve regenerative combustion.

[0044] The first side and the second side are two sides with opposite directions. For example, if the first side is the left side, the second side is the right side.

[0045] The present application has the following beneficial effects: 1. Utilize the flow of afterburning air and gas to carry away heat and cool the burner shell. Make full use of the cold fluid of afterburning air and gas to absorb the externally transmitted temperature of the heat storage body, make full use of the waste heat, and at the same time reduce the shell temperature. That is, the heat transferred out from the inside of the burner can be brought back into the combustion chamber by the normal-temperature afterburning air and gas, with high waste heat utilization rate, reduced raw material consumption, and cost savings; cancel the thick heat insulation layer on the outside, reduce the burner volume and weight.

[0046] 2. The heat storage body adopts an inner and outer concentric sleeve structure, effectively reducing the burner length and having higher space utilization rate.

[0047] 3. The gas and afterburning air are provided with independent channels and a mixing chamber. After mixing, they are sprayed into the combustion chamber and then mixed with the main air for combustion. Utilize the internal combustion structure to make the combustion gas expand, with a high flame ejection speed, increasing the disturbance of the furnace atmosphere and improving the furnace temperature uniformity.

[0048] 4. By adjusting the ratio of afterburning air to main air volume, when the excess air coefficient α < 1 in the combustion chamber 2, the fuel gas cannot be completely burned, so that the temperature in the combustion chamber 2 can be controlled, and the generation of NOx can be greatly reduced. The ejected flame gas can form a reducing atmosphere, enabling the workpieces in the furnace to be heated in a reducing atmosphere and meeting the heating requirements of furnaces with reducing requirements.

[0049] 5. When the excess air coefficient α > 1 in the combustion chamber 2, the ejected flame gas can form an oxidizing atmosphere, enabling the workpieces in the furnace to be heated in an oxidizing atmosphere and meeting the heating requirements of furnaces with oxidizing requirements.

[0050] The above embodiments are only the preferred technical solutions of the present invention and should not be regarded as limitations on the present invention. The protection scope of the present invention shall be the technical solutions recorded in the claims, including the equivalent replacement solutions of the technical features in the technical solutions recorded in the claims. That is, the equivalent replacement improvements within this scope are also within the protection scope of the present invention.

Claims

1. An outer-ring air-flow cooling regenerative burner, having a burner body. A combustion cavity is provided on the first side of the burner body, and a cover (9) is provided on the second side of the burner body. A combustion chamber (2) is provided inside the combustion cavity, and a flame nozzle (1) is communicated with the first side of the combustion chamber (2). It is characterized in that: The burner body is successively sleeved with an outer-ring cooling air cavity (6), a cylindrical outer regenerative cavity (7), and a cylindrical inner regenerative cavity (8) from outside to inside. Heat storage bodies are provided in the outer regenerative cavity (7) and the inner regenerative cavity (8), and the second sides of the outer regenerative cavity (7) and the inner regenerative cavity (8) are communicated. A main air inlet (5) is provided on the burner body, and the main air inlet (5) is communicated with the outer regenerative cavity (7). The first-side end of the inner regenerative cavity (8) is communicated with the combustion chamber (2). A gas cavity (14) and a mixing cavity (16) are further provided on the burner body. The gas cavity (14) is located outside the mixing cavity (16). The outer-ring cooling air cavity (6) and the gas cavity (14) are respectively communicated with the mixing cavity (16), and the first-side end of the mixing cavity (16) is communicated with the combustion chamber (2). A supplementary combustion air inlet (17) communicated with the outer-ring cooling air cavity (6) and a gas inlet (18) communicated with the gas cavity (14) are further provided on the burner body. The first side and the second side are two opposite sides.

2. The externally-circled air-flow cooling regenerative burner according to claim 1, wherein: The first-side end of the mixing cavity (16) is communicated with the combustion chamber (2) through a plurality of mixed-gas nozzles (3).

3. The regenerative burner with outer-ring air flow cooling according to claim 2, wherein: The mixed-gas nozzles (3) are distributed in an annular array.

4. The externally-circulated air-cooled regenerative burner according to claim 1, wherein: The outer-ring cooling air cavity (6) is spiral.

5. An outer-ring air-flow cooling regenerative burner according to any one of claims 1 to 4, characterized in that: An ignition nozzle tube (12) is sleeved inside the inner circle of the inner regenerative cavity (8). The first-side end of the ignition nozzle tube (12) is communicated with the combustion chamber (2). The second-side end of the ignition nozzle tube (12) passes through the cover (9), and an ignition assembly is further provided on the ignition nozzle tube (12) on the second side of the cover (9).

6. The regenerative burner with outer-ring air flow cooling according to claim 5, characterized in that: The ignition assembly is composed of an ignition electrode (10), an ignition gas inlet (19), and an ignition air inlet (20).

7. The externally-circulated-air-cooled regenerative burner according to claim 6, characterized in that: An observation mirror (21) is provided at the second-side end of the ignition nozzle tube (12).

8. The externally-circled air-flow cooled regenerative burner according to claim 7, wherein: The main air inlet (5) is located above the first side of the burner body.

9. The regenerative burner with outer-ring air flow cooling according to claim 8, characterized in that: The gas inlet (18) is located at the rear side of the burner body and on the first side of the main air inlet (5).

10. The externally-circulated air-cooled regenerative burner according to claim 9, wherein: The supplementary combustion air inlet (17) is located at the front side of the burner body and on the second side of the main air inlet (5).

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