Flue gas heat accumulating type heat compensation device and diffusion combustion purification system
By setting up a regenerative combustion chamber and burner in the SCR flue, and using flue gas to assist combustion for oxygen-deficient combustion, the problems of poor combustion stability and heavy equipment burden in the existing technology are solved. Stable combustion and efficient heating of low-calorific-value gas are achieved, reducing equipment costs and the burden on the SCR reactor.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-06
- Publication Date
- 2026-03-10
AI Technical Summary
Existing SCR flue gas heating technology suffers from problems such as poor combustion stability, narrow adaptability to raw materials, large equipment footprint, high material costs, and heavy equipment burden, especially in the application of low-calorific-value gas.
A regenerative combustion chamber and burner are installed in the SCR flue. Oxygen-deficient combustion is achieved by assisting combustion with flue gas. The flue gas itself is used as the combustion medium. Combined with a multi-channel burner and oxygen supply pipeline, diffuse combustion of the gas is achieved. A flue gas regenerative heat supplementation device and a diffuse combustion purification system are adopted to improve combustion stability and heating uniformity.
Stable combustion of low-calorific-value fuel gas was achieved, reducing equipment burden and material costs, improving heating stability and uniformity, reducing the load on the SCR reactor, and reducing the generation of thermal NOx.
Smart Images
Figure CN223985190U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to a combustion device and combustion system, specifically to a flue gas heat storage and supplementary heating device and a diffuse combustion purification system, belonging to the field of flue gas treatment technology. Background Technology
[0002] Following the release of the "Opinions on Promoting the Implementation of Ultra-Low Emissions in the Steel Industry" by five national ministries, it is required that ultra-low emission transformation of steel enterprises in key regions be basically completed by the end of 2025, and that more than 80% of the national production capacity be transformed. Among these transformations, NO2 in processes such as sintering, coking, and lime kilns is a key focus. x Emission standards must be less than 50 mg / Nm 3 Currently, the most mature flue gas denitrification technology is selective catalytic reduction (SCR) denitrification technology. However, the flue gas emission temperature of many processes in the steel industry is generally in the range of 90~180℃, which does not reach the ideal catalytic temperature (220~450℃) of traditional SCR denitrification technology. Generally, the flue gas needs to be reheated first to raise the temperature to the target temperature before entering the catalytic reactor for denitrification reaction.
[0003] Currently, traditional flue gas reheating methods generally utilize a flue gas reheating hot air furnace to heat the flue gas. These furnaces typically use coal gas as fuel and are further divided into external and internal types. Specifically, the external hot air furnace has a complete combustion chamber outside the SCR flue (e.g., Figure 5 As shown in the figure, after the flame is fully burned in the furnace, the high-temperature flue gas is sent into the flue through the high-temperature flue gas pipe. After the high-temperature flue gas mixes with the flue gas in the flue, it rises to the target temperature and enters the SCR reactor for denitrification reaction.
[0004] Built-in hot air furnaces do not have a complete combustion chamber; the burner is directly installed on the SCR flue (e.g., Figure 6 As shown in the figure, fuel and combustion air are directly injected into the flue for combustion and heat release. The flue gas is heated to the target temperature and then enters the SCR reactor for denitrification reaction.
[0005] Both existing SCR flue gas heating technologies require the addition of a certain amount of fuel gas, followed by the addition of a specific proportion of air to aid combustion according to the air-fuel ratio. The resulting high-temperature flue gas then enters the SCR flue, adding fuel gas and air to the existing flue gas, thus increasing the burden on the SCR reactor. External hot air furnaces, with their independent combustion chambers, have a large footprint, high equipment load, large heat dissipation area, and high material costs. While internal hot air furnaces address these issues, their flames burn directly in the flue, leading to poor combustion stability and potential safety hazards. They also have a narrower range of feedstock adaptability, are unsuitable for low-calorific-value fuel gas, and the high-temperature flue gas remains disordered within the flue, resulting in poor heating uniformity. Utility Model Content
[0006] To address the problems of poor combustion stability and narrow raw material adaptability in existing hot blast stoves, this invention proposes a regenerative flue gas supplementary heating device. By setting up a regenerative combustion chamber within the flue, oxygen-deficient combustion can be achieved, along with stable combustion of low-calorific-value fuel gas. This significantly enhances raw material adaptability, and the required combustion fuel is the flue gas itself, avoiding the problem of increased flue gas volume caused by introducing large amounts of air. Furthermore, to address the issues of large footprint, heavy equipment load, and high material costs associated with existing hot blast stoves, this invention also proposes a dispersion combustion purification system incorporating the regenerative flue gas supplementary heating device. Since the regenerator is directly installed inside the flue, it does not occupy additional space. The system utilizes the regenerator to store heat before injecting hot gas into the flue through the fire channel for dispersion combustion heating, improving fuel combustion stability while reducing the reactor's load.
[0007] According to the first embodiment of this utility model, a flue gas heat storage and supplementary heating device is provided.
[0008] A flue gas regenerative heat supply device includes a flue, a heat storage body, and a burner. The heat storage body is disposed within the flue and has a combustion heat storage chamber inside. A fire channel is also formed on the side wall of the heat storage body, connecting the combustion heat storage chamber to the flue. The burner nozzle passes through the flue and the side wall of the heat storage body and connects to the combustion heat storage chamber. The other end of the burner is located outside the flue and has a fuel inlet and a combustion-supporting gas inlet. The combustion-supporting gas inlet is connected to the upstream of the flue via a combustion-supporting gas delivery pipe.
[0009] Preferably, the flue contains multiple heat storage bodies, each corresponding to a burner. Preferably, the multiple heat storage bodies are evenly distributed within the same radial cross-section of the flue. Preferably, the number of heat storage bodies is 2 to 8, more preferably 3 to 6.
[0010] Preferably, the fire channel is located on the side wall of the heat storage body near the side where the flue gas flows out, according to the direction of the flue gas.
[0011] Preferably, the heat storage body has a cylindrical structure, and multiple fire channels are evenly arranged on the side wall of the heat storage body near the flue gas outlet. Preferably, the number of fire channels is 1 to 60, more preferably 5 to 50. Preferably, the axial direction of the heat storage body is parallel to the radial direction of the flue gas outlet.
[0012] Preferably, the fire channel has a diffusion structure.
[0013] Preferably, an air-breaking section is provided on the side wall of the heat storage body near the flue gas source. Preferably, the air-breaking section is a conical structure that protrudes towards the flue gas source.
[0014] Preferably, a first temperature detector is also provided inside the heat storage body.
[0015] Preferably, an oxygen content detector is also installed inside the heat storage body.
[0016] Preferably, the burner is mounted on the axial sidewall of the combustion regenerator, and the fuel inlet of the burner is connected to 1 to 5 gas delivery pipes, with the inlet ends of different gas delivery pipes connected to different gas medium sources. Each gas delivery pipe is independently equipped with a flow regulating valve.
[0017] Preferably, the device also includes an oxygen supply pipeline. The inlet end of the oxygen supply pipeline is connected to an oxygen-containing gas source, and the outlet end of the oxygen supply pipeline is connected to a combustion-supporting gas delivery pipeline.
[0018] Preferably, flow regulating valves are independently installed on both the oxygen supply pipeline and the gas-supporting combustion transmission pipeline, wherein, according to the direction of airflow, the flow regulating valve on the gas-supporting combustion transmission pipeline is located upstream of the connection between the oxygen supply pipeline and the gas-supporting combustion transmission pipeline.
[0019] Preferably, a combustion-supporting fan is also installed on the combustion-supporting gas transmission pipeline, and the combustion-supporting fan is located downstream of the connection between the oxygen supply pipeline and the combustion-supporting gas transmission pipeline, depending on the direction of the airflow.
[0020] According to a second embodiment of the present invention, a dispersion combustion purification system is provided.
[0021] A diffused combustion purification system includes a flue gas regenerative heating device and an SCR reactor. The SCR reactor is located on the flue and downstream of the regenerative body.
[0022] Preferably, the system further includes a heat exchanger with separate high-temperature medium channels and low-temperature medium channels. The high-temperature medium channel is connected to a flue located downstream of the SCR reactor. The low-temperature medium channel is connected to a flue located upstream of the heat storage body.
[0023] Preferably, the connection between the low-temperature medium channel and the flue is located between the heat storage body and the combustion gas transmission pipeline.
[0024] Preferably, the heat exchanger is a GGH heat exchanger.
[0025] Preferably, a CO concentration detector is also installed in the flue upstream of the heat exchanger.
[0026] Preferably, a second temperature detector is also provided in the flue located between the heat storage body and the SCR reactor.
[0027] In this invention, a heat storage body and a burner are installed inside the flue, and a combustion-supporting gas supply pipeline connects the upstream of the flue, the burner, and the combustion heat storage chamber. In practical applications, different calorific values of gas can be injected into the combustion heat storage chamber through the burner. Simultaneously, since the oxygen content of the flue gas emitted during the sintering steel process is generally 15-18%, flue gas is introduced through the combustion-supporting gas supply pipeline to aid combustion. During the heating stage, the high-temperature flue gas generated by combustion within the chamber is ejected from the fire channel and enters the flue. The flue gas requiring heating enters the flue chamber and contacts the heat storage body, while the high-temperature gas discharged from the combustion heat storage chamber further heats the flue gas. Furthermore, the use of flue gas for combustion allows for oxygen-deficient combustion of the gas within the combustion heat storage chamber. Unburned gas is ejected from the heat storage body along with the high-temperature flue gas. Due to the high ejection temperature, it continues to burn upon contact with the flue gas in the flue. This double combustion process within the combustion heat storage chamber and the flue improves combustion stability and eliminates safety hazards. The flue gas regenerator supplementary heating device provided by this utility model can fully heat the flue gas without posing any safety hazards, reduce the burden on the reactor, and has a small footprint and low material cost, making it highly practical.
[0028] In this invention, multiple heat storage bodies can be installed within the flue to improve the heating efficiency of the flue gas and achieve uniform heating. Preferably, the fire channels are located on the downstream side wall of the heat storage body along the flue gas flow, allowing the heat storage body to better discharge high-temperature flue gas. Preferably, the heat storage body is cylindrical, and multiple fire channels are arranged on the downstream side wall of the heat storage body along the flue gas flow, further improving the uniformity of flue gas heating. Due to the uniform arrangement of the fire channels and heat storage bodies, the high-temperature gas ejected from the heat storage body can be uniformly dispersed across the entire flue cross-section, achieving diffuse combustion of the fuel gas. Preferably, the fire channels can also be configured as a diffusion structure, i.e., the aperture of the fire channels gradually increases in the direction away from the combustion heat storage chamber, thereby causing the high-temperature gas ejected from the heat storage body to diffuse, further improving the uniformity of the gas in the flue.
[0029] In this invention, a conical air-breaking section is preferably provided on the side of the heat storage body near the gas inlet, which can reduce the resistance of the flue gas in the flue.
[0030] In this invention, the burner is preferably a multi-channel burner, which can use a single gas medium or two or more gas media simultaneously. When using multiple gas media, the various gases can be premixed inside the burner nozzle before being injected into the combustion regenerator. The simultaneous use of multiple gases ensures combustion stability. Furthermore, the gas injection rate is adjustable via flow regulating valves in each gas delivery pipe.
[0031] This invention includes a diffuse combustion purification system comprising a flue gas regenerative heating device. For flue gas emitted during steelmaking processes, the regenerative heating device heats the flue gas to be purified, achieving sufficient heating. Furthermore, by controlling the amount of flue gas and / or oxygen-containing gas input to the burner, the combustion gas can undergo either oxygen-deficient or full combustion within the regenerative body. During oxygen-deficient combustion, unburned gas is ejected from the regenerative body's combustion chamber along with the high-temperature flue gas and continues to burn upon contact with the flue gas to be purified. Due to the uniform arrangement of the combustion chamber and the regenerative body, the ejected high-temperature gas is evenly dispersed throughout the flue, achieving diffuse combustion, avoiding excessively high temperatures during combustion, avoiding explosion limits, and improving the stability of flue gas heating.
[0032] In this invention, due to the diffuse combustion of the fuel gas within the flue, a portion of the residual CO in the flue gas to be purified is oxidized (according to engineering measurements, this typically burns off 3000-5000 ppm of CO from the original flue gas). This CO oxidation releases heat, aiding in the heating process of the original flue gas, thus saving gas consumption and reducing carbon emissions. Furthermore, by using the original flue gas as the combustion medium, this system reduces the amount of combustion air entering the system, lessening the load on the SCR reactor. The combustion process consumes O2 in the flue gas, reducing the O2 content in the emissions. The diffuse combustion also avoids excessively high temperatures during combustion, reducing thermal NOx emissions. x The generation of [something] can also reduce the load on the SCR reactor.
[0033] In this invention, an oxygen supply pipeline connected to the combustion-supporting gas delivery pipeline is further provided. During start-up, a certain amount of raw flue gas can be drawn from the flue gas source and sent to the combustion-supporting gas main pipe, where it burns together with the gas supplied to the burner in the regenerator chamber to heat the regenerator. Using flue gas for combustion without adding extra air reduces the load on the SCR reactor. Furthermore, to address the difficulty of igniting low-calorific-value combustion gases under raw flue gas during start-up, cold air or other oxygen-containing gases are introduced through the oxygen supply pipeline. The flow regulating valves in the oxygen supply pipeline and the combustion-supporting gas delivery pipeline can also be used to switch between flue gas-supported combustion and air-supported combustion (i.e., to freely switch between full combustion and oxygen-deficient combustion within the regenerator). Furthermore, a combustion-supporting fan is installed on the combustion-supporting gas delivery pipeline. By changing the power of the combustion-supporting fan and / or the opening of the flow regulating valves in the oxygen supply pipeline and the combustion-supporting gas delivery pipeline, the oxygen content within the regenerator can be better adjusted.
[0034] In this invention, a heat exchanger can be installed to utilize the waste heat of the high-temperature gas discharged from the SCR reactor to preheat the flue gas to be purified, thereby making full use of the waste heat and improving the heating efficiency of the flue gas to be heated.
[0035] Compared with the prior art, the present invention has the following beneficial effects:
[0036] 1. The present invention provides a flue gas heat storage and supplementary heating device, which sets up a heat storage body inside the flue and introduces flue gas for combustion through a combustion-supporting gas delivery pipe, so that the gas undergoes oxygen-deficient combustion in the combustion heat storage chamber. The unburned gas is ejected from the heat storage body along with the high-temperature flue gas and diffuses and burns in the flue. Through two combustions, the combustion stability is improved. While fully heating the flue gas, there are no safety hazards. It can reduce the burden on the reactor, and has a small footprint and low material cost, making it highly practical.
[0037] 2. The present invention provides a flue gas heat storage supplementary heating device, which, through an oxygen supply pipeline and multiple heat storage bodies, enables free switching between full combustion of gas and oxygen-deficient combustion within the heat storage body, as well as diffuse combustion of coal gas, avoiding excessive high temperature generated during combustion, avoiding explosion limits, and improving the stability of flue gas heating.
[0038] 3. This utility model provides a diffuse combustion purification system, which includes a flue gas regenerative heating device. For flue gas emitted during steel supply and demand, the flue gas to be purified is heated by the regenerative heating device, achieving sufficient heating of the flue gas. Furthermore, the system allows for oxygen-deficient or complete combustion of the fuel gas within the heat storage body, achieving diffuse combustion, avoiding excessively high temperatures during combustion, avoiding explosion limits, and improving the stability of flue gas heating. Attached Figure Description
[0039] Figure 1 This is a schematic diagram of the structure of a flue gas heat storage and reheating device provided by this utility model.
[0040] Figure 2 A cross-sectional view of AA in a flue gas heat storage and supplementary heating device provided by this utility model.
[0041] Figure 3 The present invention provides a flue gas heat storage and supplementary heating device. Figure 2 View B.
[0042] Figure 4 This is a schematic diagram of the structure of a dispersion combustion purification system provided by this utility model.
[0043] Figure 5 This is a schematic diagram of a structure in the prior art that uses an external hot air furnace for flue gas heating.
[0044] Figure 6 This is a schematic diagram of a structure in the prior art that uses a built-in hot air furnace for flue gas heating.
[0045] Reference numerals: 1: Flue; 2: Regenerator; 201: Combustion regenerator chamber; 202: Fire duct; 203: Air breaker; 3: Burner; 4: Combustion fan; L1: Combustion gas delivery pipe; L2: Oxygen supply pipe; L3: Combustion gas delivery pipe; 5: SCR reactor; 6: Heat exchanger; 7: First temperature detector; 8: Oxygen content detector; 9: CO concentration detector; 10: Second temperature detector. Detailed Implementation
[0046] The technical solution of the present invention will be illustrated below with examples. The scope of protection sought by the present invention includes, but is not limited to, the following embodiments.
[0047] According to the first embodiment of this utility model, a flue gas heat storage and supplementary heating device is provided.
[0048] A flue gas regenerative heating device includes a flue duct 1, a heat storage body 2, and a burner 3. The heat storage body 2 is disposed within the flue duct 1, and a combustion heat storage chamber 201 is formed inside the heat storage body 2. A fire channel 202 is also formed on the side wall of the heat storage body 2, and the combustion heat storage chamber 201 is connected to the flue duct 1 through the fire channel 202. The nozzle end of the burner 3 passes through the side wall of the flue duct 1 and the heat storage body 2 and is connected to the combustion heat storage chamber 201. The other end of the burner 3 is located outside the flue duct 1 and has a fuel inlet and a combustion-supporting gas inlet. The combustion-supporting gas inlet is connected to the upstream of the flue duct 1 through a combustion-supporting gas delivery pipe L1.
[0049] Preferably, the flue 1 is provided with a plurality of heat storage bodies 2, and each heat storage body 2 is correspondingly provided with a burner 3. Preferably, the plurality of heat storage bodies 2 are evenly arranged in the same radial cross section of the flue 1. Preferably, the number of heat storage bodies 2 is 2 to 8, and more preferably 3 to 6.
[0050] Preferably, the fire channel 202 is disposed on the side wall of the heat storage body 2 near the side where the flue gas flows out, according to the direction of the flue gas.
[0051] Preferably, the heat storage body 2 has a cylindrical structure, and multiple fire channels 202 are evenly arranged on the side wall of the heat storage body 2 near the flue gas outlet. Preferably, the number of fire channels 202 is 1 to 60, more preferably 5 to 50. Preferably, the axial direction of the heat storage body 2 is parallel to the radial direction of the flue 1.
[0052] Preferably, the fire channel 202 has a diffusion structure.
[0053] Preferably, a wind-breaking section 203 is also provided on the side wall of the heat storage body 2 near the flue gas source. Preferably, the wind-breaking section 203 is a conical structure that protrudes towards the flue gas source.
[0054] Preferably, a first temperature detector 7 is also provided inside the heat storage body 2.
[0055] Preferably, an oxygen content detector 8 is also provided inside the heat storage body 2.
[0056] Preferably, the burner 3 is mounted on the axial side wall of the combustion regenerator chamber 201, and the fuel inlet of the burner 3 is connected to 1 to 5 gas delivery pipes L3. The inlet end of each gas delivery pipe L3 is connected to a different gas medium source. Each gas delivery pipe L3 is independently equipped with a flow regulating valve.
[0057] Preferably, the device also includes an oxygen supply pipeline L2. The inlet end of the oxygen supply pipeline L2 is connected to an oxygen-containing gas source, and the outlet end of the oxygen supply pipeline L2 is connected to a combustion-supporting gas delivery pipeline L1.
[0058] Preferably, flow regulating valves are independently installed on both the oxygen supply pipeline L2 and the gas-supporting pipeline L1, wherein, according to the direction of airflow, the flow regulating valve on the gas-supporting pipeline L1 is located upstream of the connection between the oxygen supply pipeline L2 and the gas-supporting pipeline L1.
[0059] Preferably, a combustion-supporting fan 4 is also provided on the combustion-supporting gas transmission pipeline L1. According to the direction of airflow, the combustion-supporting fan 4 is located downstream of the connection between the oxygen supply pipeline L2 and the combustion-supporting gas transmission pipeline L1.
[0060] According to a second embodiment of the present invention, a dispersion combustion purification system is provided.
[0061] A diffuse combustion purification system includes a flue gas regenerative heating device and an SCR reactor 5. The SCR reactor 5 is installed on the flue duct 1 and located downstream of the heat storage body 2.
[0062] Preferably, the system further includes a heat exchanger 6, which has non-interconnected high-temperature medium channels and low-temperature medium channels. The high-temperature medium channel is connected to the flue 1 located downstream of the SCR reactor 5. The low-temperature medium channel is connected to the flue 1 located upstream of the heat storage body 2.
[0063] Preferably, the connection between the low-temperature medium channel and the flue 1 is located between the heat storage body 2 and the combustion gas transmission pipeline L1.
[0064] Preferably, the heat exchanger 6 is a GGH heat exchanger.
[0065] Preferably, a CO concentration detector 9 is also provided in the flue 1 upstream of the heat exchanger 6.
[0066] Preferably, a second temperature detector 10 is also provided in the flue 1 located between the heat storage body 2 and the SCR reactor 5. Example 1
[0067] likeFigures 1-3 As shown, a flue gas regenerative heating device includes a flue duct 1, a heat storage body 2, and a burner 3. The heat storage body 2 is disposed within the flue duct 1, and a combustion heat storage chamber 201 is formed inside the heat storage body 2. A fire channel 202 is also formed on the side wall of the heat storage body 2, and the combustion heat storage chamber 201 is connected to the flue duct 1 through the fire channel 202. The nozzle end of the burner 3 passes through the side wall of the flue duct 1 and the heat storage body 2 and is connected to the combustion heat storage chamber 201. The other end of the burner 3 is located outside the flue duct 1 and has a fuel inlet and a combustion-supporting gas inlet. The combustion-supporting gas inlet is connected to the upstream of the flue duct 1 through a combustion-supporting gas delivery pipe L1. Example 2
[0068] The embodiment 1 is repeated, except that the flue 1 is provided with four heat storage bodies 2, and each heat storage body 2 is provided with a corresponding burner 3. The four heat storage bodies 2 are evenly arranged in the same radial cross section of the flue 1.
[0069] According to the direction of the flue gas, the fire channel 202 is set on the side wall of the heat storage body 2 near the side where the flue gas flows out. Example 3
[0070] Example 2 is repeated, except that the heat storage body 2 is a cylindrical structure, and 35 fire channels 202 are evenly arranged on the side wall of the heat storage body 2 near the flue gas outlet. The axial direction of the heat storage body 2 is parallel to the radial direction of the flue 1.
[0071] The fire channel 202 has a diffusion structure. Example 4
[0072] The embodiment 3 is repeated, except that a wind-breaking section 203 is also provided on the side wall of the heat storage body 2 near the flue gas source. The wind-breaking section 203 is a conical structure that protrudes towards the flue gas source. Example 5
[0073] The embodiment 4 is repeated, except that a first temperature detector 7 is also provided inside the heat storage body 2.
[0074] An oxygen content detector 8 is also installed inside the heat storage body 2. Example 6
[0075] The embodiment 5 is repeated, except that the burner 3 is installed on the axial side wall of the combustion regenerator 201, and the fuel inlet of the burner 3 is connected to two gas delivery pipes L3. The gas inlet ends of the two gas delivery pipes L3 are respectively connected to a coal gas source and a natural gas source. Each gas delivery pipe L3 is independently equipped with a flow regulating valve. Example 7
[0076] The same method as Embodiment 6 is used, except that the device also includes an oxygen supply pipeline L2. The inlet end of the oxygen supply pipeline L2 is connected to an oxygen-containing gas source, and the outlet end of the oxygen supply pipeline L2 is connected to a combustion-supporting gas delivery pipeline L1. Example 8
[0077] Repeat Example 7, except that flow regulating valves are independently provided on both the oxygen supply pipeline L2 and the gas-supporting pipeline L1. The flow regulating valve on the gas-supporting pipeline L1 is located upstream of the connection between the oxygen supply pipeline L2 and the gas-supporting pipeline L1, depending on the direction of the airflow.
[0078] A combustion-supporting fan 4 is also installed on the combustion-supporting gas transmission pipeline L1. According to the direction of airflow, the combustion-supporting fan 4 is located downstream of the connection between the oxygen supply pipeline L2 and the combustion-supporting gas transmission pipeline L1. Example 9
[0079] like Figure 4 As shown, a diffuse combustion purification system includes the flue gas regenerative heat replenishment device described in Example 8 and an SCR reactor 5. The SCR reactor 5 is installed on the flue duct 1 and located downstream of the heat storage body 2. Example 10
[0080] The system repeats Example 9, except that it also includes a heat exchanger 6, which has separate high-temperature and low-temperature medium channels. The high-temperature medium channel is connected to the flue 1 located downstream of the SCR reactor 5. The low-temperature medium channel is connected to the flue 1 located upstream of the heat storage body 2.
[0081] The connection between the low-temperature medium channel and the flue 1 is located between the heat storage body 2 and the combustion gas transmission pipeline L1.
[0082] The heat exchanger 6 is a GGH heat exchanger. Example 11
[0083] Example 10 is repeated, except that a CO concentration detector 9 is also provided in the flue 1 upstream of the heat exchanger 6.
[0084] A second temperature detector 10 is also provided in the flue 1 located between the heat storage body 2 and the SCR reactor 5.
[0085] The process of treating flue gas using the dispersion combustion purification system of this invention is as follows: Flue gas from the steelmaking process is introduced into the flue duct 1 of the dispersion combustion purification system. A portion of the flue gas enters the combustion gas inlet of the burner 3 from the combustion gas supply pipe L1, while simultaneously, combustion gas (including high- and / or low-calorific-value gases) is introduced into the burner 3 through the combustion gas supply pipe L3. The burner then introduces the combustion gas and flue gas into the combustion regenerator chamber 201. After reacting in the combustion regenerator chamber 201, the combustion gas is discharged from the regenerator chamber 202 through the fire channel 202. Another portion of the flue gas continues to flow after passing through the low-temperature medium channel of the heat exchanger, mixing and heating with the high-temperature gas discharged from the fire channel 202, and undergoing dispersion combustion with the unreacted combustion gas in the high-temperature gas. After combustion, the flue gas is heated and then introduced into the SCR reactor for denitrification. The high-temperature gas discharged from the SCR reactor is introduced into the high-temperature medium channel of the heat exchanger to obtain clean flue gas.
Claims
1. A flue gas heat regenerative reheat device characterized by: The device comprises a flue (1), a heat accumulator (2) and a burner (3); the heat accumulator (2) is arranged in the flue (1), and a combustion heat accumulating chamber (201) is formed in the interior of the heat accumulator (2), a flue (202) is further formed in the side wall of the heat accumulator (2), and the combustion heat accumulating chamber (201) is connected with the flue (1) through the flue (202); the burner (3) is connected with the combustion heat accumulating chamber (201) through the side wall of the flue (1) and the heat accumulator (2), and the other end of the burner (3) is arranged outside the flue (1) and is provided with a fuel inlet and a combustion-supporting gas inlet; the combustion-supporting gas inlet is connected with the upstream of the flue (1) through a combustion-supporting gas conveying pipeline (L1).
2. The apparatus of claim 1, wherein: A plurality of heat accumulators (2) are arranged in the flue (1), and each heat accumulator (2) is correspondingly provided with one burner (3).
3. The apparatus of claim 2, wherein: The plurality of heat accumulators (2) are uniformly arranged in the same radial section of the flue (1).
4. The apparatus of claim 2, wherein: The number of the heat accumulators (2) is 2-8.
5. The apparatus of claim 4, wherein: The number of the heat accumulators (2) is 3-6.
6. The apparatus of claim 1, wherein: According to the flow direction of the flue gas, the flue (202) is arranged on the side wall of the heat accumulator (2) close to the flue gas flow direction.
7. The apparatus of claim 1, wherein: The heat accumulator (2) is in a cylindrical structure, and a plurality of flues (202) are uniformly arranged on the side wall of the heat accumulator (2) close to the flue gas flow direction.
8. The apparatus of claim 7, wherein: The number of the flues (202) is 1-60.
9. The apparatus of claim 8, wherein: The number of the flues (202) is 5-50.
10. The apparatus of claim 1, wherein: The axial direction of the heat accumulator (2) is parallel to the radial direction of the flue (1).
11. The apparatus of claim 1, wherein: The flue (202) is in a diffusion structure.
12. The apparatus of claim 1, wherein: A wind breaking part (203) is further arranged on the side wall of the heat accumulator (2) close to the flue gas source.
13. The apparatus of claim 12, wherein: The wind breaking part (203) is in a conical structure protruding towards the flue gas source.
14. The apparatus of claim 1, wherein: A first temperature detector (7) is further arranged in the interior of the heat accumulator (2); and / or An oxygen content detector (8) is further arranged in the interior of the heat accumulator (2).
15. The apparatus of claim 1, wherein: The burner (3) is arranged on the axial side wall of the combustion heat accumulating chamber (201), the fuel inlet of the burner (3) is connected with 1-5 gas conveying pipelines (L3), the gas inlet ends of different gas conveying pipelines (L3) are respectively connected with different gas medium sources, and a flow regulating valve is independently arranged on each gas conveying pipeline (L3).
16. The apparatus of claim 1, wherein: The device further comprises an oxygen supply pipeline (L2), the gas inlet end of the oxygen supply pipeline (L2) is connected with an oxygen-containing gas source, and the gas outlet end of the oxygen supply pipeline (L2) is connected with the combustion-supporting gas conveying pipeline (L1).
17. The apparatus of claim 16, wherein: Flow regulating valves are independently arranged on the oxygen supply pipeline (L2) and the combustion-supporting gas conveying pipeline (L1), wherein, according to the flow direction of the gas flow, the flow regulating valve on the combustion-supporting gas conveying pipeline (L1) is located upstream of the connection position of the oxygen supply pipeline (L2) and the combustion-supporting gas conveying pipeline (L1).
18. The apparatus of claim 17, wherein: A combustion-supporting fan (4) is further arranged on the combustion-supporting gas conveying pipeline (L1), and according to the flow direction of the gas flow, the combustion-supporting fan (4) is located downstream of the connection position of the oxygen supply pipeline (L2) and the combustion-supporting gas conveying pipeline (L1).
19. A diffusion combustion trim system characterized by: The system comprises the flue gas heat accumulating heat supplementing device according to any one of claims 1-18 and an SCR reactor (5); the SCR reactor (5) is arranged on the flue (1) and is located downstream of the heat accumulating body (2).
20. The system of claim 19, wherein: The system further comprises a heat exchanger (6) having a high-temperature medium channel and a low-temperature medium channel which are not communicated with each other; the high-temperature medium channel is connected with the flue (1) located downstream of the SCR reactor (5); and the low-temperature medium channel is connected with the flue (1) located upstream of the heat accumulating body (2).
21. The system of claim 20, wherein: The connection of the low-temperature medium channel with the flue (1) is located between the heat accumulating body (2) and the combustion-supporting gas delivery pipeline (L1).
22. The system of claim 20, wherein: The heat exchanger (6) is a GGH heat exchanger.
23. The system of any one of claims 20-22, wherein: The flue (1) upstream of the heat exchanger (6) is further provided with a CO concentration detector (9); and / or The flue (1) between the heat accumulating body (2) and the SCR reactor (5) is further provided with a second temperature detector (10).