Oxygen-enriched combustion system and method for coal gas single heat storage type heating furnace

Abstract

The invention belongs to the technical field of heating furnaces, and particularly relates to an oxygen-enriched combustion system and method for a coal gas single heat storage type heating furnace. Comprising an oxygen pressure regulating branch, a first heating section oxygen lance oxygen injection branch and a main pipe oxygen enrichment branch, the oxygen pressure regulating branch is provided with a pressure transmitter and a temperature transmitter, an oxygen source is communicated with the pressure transmitter and the temperature transmitter through a pipeline, and oxygen flows into the first heating section oxygen lance oxygen injection branch and the main pipe oxygen enrichment branch after being subjected to pressure regulation through a pressure valve. A flow control valve is arranged on the first heating section oxygen lance oxygen injection branch, oxygen is fed into the heating furnace, and the main pipe oxygen enrichment branch feeds enriched oxygen into the main pipe through an enriched oxygen distributor. Flexible switching of different oxygen enrichment modes of the heating furnace is achieved, the burner in the oxygen lance oxygen injection branch of the first heating section is not reversed, total-oxygen combustion of the burner is achieved, under the oxygen enrichment branch of the main pipe, oxygen is conveyed to the main pipe through the oxygen enrichment distributor through the other branch to be mixed with combustion air, and total-furnace oxygen enrichment combustion is achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of heating furnaces, and in particular relates to an oxygen-enriched combustion system and method for a coal gas single regenerative heating furnace. Background Art

[0002] The steel industry has always been a major energy consumer in my country, among which the heating furnace occupies an important position. It is the key equipment on the hot rolling line and has a great impact on the quality of the final product and the total energy consumption. Its energy consumption accounts for about 60% of the energy consumption of the entire process. With the intensification of market competition in the steel industry, the heated steel types are mainly high-value-added varieties of steel, with high steel tapping temperatures and long furnace time. Conventional regenerative heating furnaces have problems such as insufficient production capacity, high energy consumption, high burnout, and large pollutant emissions.

[0003] Oxygen-enriched combustion is one of the modern energy-saving combustion technologies. For the high-energy consumption and high-pollution steel industry, it is one of the best ways to improve energy efficiency, reduce fuel consumption and reduce pollutant emissions. Due to the high oxygen content, the nitrogen content that does not participate in combustion is relatively reduced, and the combustion efficiency and heat transfer efficiency are greatly improved. Due to the reduction of nitrogen, the heating capacity can be increased, the furnace thermal efficiency can be greatly improved, the gas consumption can be reduced, and the CO2 emission can be reduced, so as to achieve the purpose of saving fuel. On the one hand, oxygen-enriched combustion can accelerate the combustion speed of coal gas, promote complete combustion, and increase the flame temperature; on the other hand, it can reduce the exhaust volume after combustion, reduce the furnace pressure, and reduce the heat loss of the furnace, which has excellent energy-saving properties. The proportion of triatomic and polyatomic gases with radiation ability in the oxygen-enriched combustion products increases, and the proportion of monatomic gas N2 with almost no radiation ability decreases. The increase in flame temperature and the increase in smoke blackness effectively improve the radiation heat exchange capacity of smoke to slabs, shorten the heating time, improve efficiency, and increase output.

[0004] A Chinese patent with announcement number CN118497443A discloses a hot blast furnace combustion control method based on oxygen-enriched full-burning blast furnace gas, comprising the following steps: the hot blast furnace adopts an oxygen-enriched combustion process, the combustion-supporting agent is oxygen-enriched combustion-supporting air, and the outlet pressure of the oxygen-enriched combustion-supporting air pipeline is controlled to be 9.20-10.50 KPa; a hot blast furnace staggered furnace replacement operation system is formulated to maintain the pressure of the blast furnace gas main network of the whole plant stable; the blast furnace gas is connected to the hot blast furnace gas main through a pipeline, and the outlet pressure of the hot blast furnace gas main is controlled to be 9.20-10.50 KPa; the oxygen-enriched combustion-supporting air is preheated to 180-250°C, and the blast furnace gas is preheated to 180-250°C; the flow ratio of blast furnace gas to oxygen-enriched combustion-supporting air is adjusted to 1.42-1.67, and the furnace is burned. The oxygen-enriched combustion method of the regenerative heating furnace of the above invention is not flexible in adjusting the production increase and consumption reduction method. When the production increase and consumption reduction are met, it is easy to cause local high temperature and poor temperature uniformity of the billet. In serious cases, it affects the normal production of the subsequent rolling mill. Therefore, it is urgent for those skilled in the art to solve the above technical problems. Summary of the invention

[0005] The technical problem to be solved by the present invention is that in the above-mentioned prior art, the oxygen-enriched combustion mode of the regenerative heating furnace is not flexible in adjusting the mode of increasing production and reducing consumption. When meeting the conditions of increasing production and reducing consumption, it is easy to cause local high temperature and poor temperature uniformity of the billet, which in serious cases affects the normal production of the subsequent rolling mill.

[0006] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0007] An oxygen-enriched combustion system for a coal gas single regenerative heating furnace comprises an oxygen pressure regulating branch, a first heating section oxygen lance oxygen emitting branch and a main oxygen-enriched branch, wherein the oxygen pressure regulating branch is provided with a pressure transmitter and a temperature transmitter, and an oxygen source is connected to the oxygen pressure regulating branch through a pipeline, and oxygen flows into the first heating section oxygen lance oxygen emitting branch or the main oxygen-enriched branch after pressure regulation, and when the first heating section oxygen lance oxygen emitting branch is started, the main oxygen-enriched branch is closed, and after the oxygen flow rate in the first heating section oxygen lance oxygen emitting branch is adjusted, the oxygen is sent into the heating furnace, and when the main oxygen-enriched branch is opened, the first heating section oxygen lance oxygen emitting branch is closed, and the enriched oxygen is sent into the main pipeline through the oxygen-enriched distributor.

[0008] By adopting the above technical solution, by increasing the oxygen concentration, the fuel can be burned more completely, thereby improving the thermal efficiency. This helps to reduce unburned fuel and pollutant emissions. Since the combustion process is more efficient, the amount of fuel required can be reduced, thereby reducing energy consumption costs. Accurately controlling the temperature distribution in the heating furnace is essential to ensure the quality of the final product. Oxygen-enriched combustion can provide a more uniform and stable heat source, which helps to improve product quality. Traditional combustion methods may produce more carbon monoxide (CO) and other harmful gases. After using oxygen-enriched combustion technology, the amount of these emissions usually decreases significantly, which is beneficial to environmental protection. The system allows the selection of local (first heating section) or full furnace range oxygen-enriched combustion mode according to actual needs, providing greater operational flexibility. For example, when it is necessary to emphasize the heating effect of a certain area, the local mode can be selected; when it is desired to improve the heating efficiency as a whole, it can be switched to the full furnace mode. Compared with ordinary air combustion, the flame produced by oxygen-enriched combustion has a higher temperature but a smaller volume, which means that the direct impact on the internal structure of the furnace body is smaller, which helps to extend the service life of the heating furnace and related equipment.

[0009] Furthermore, the oxygen pressure regulating branch also includes a manual shut-off valve 1, a pressure gauge 1, a filter, a pressure gauge 2, a pressure regulating valve, a pressure gauge 3 and a safety shut-off valve 1, and the manual shut-off valve 1, the pressure gauge 1, the filter, the pressure gauge 2, the pressure regulating valve, the pressure gauge 3 and the safety shut-off valve 1 are connected in sequence through a pipeline.

[0010] By adopting the above technical solution, a means of quickly isolating the oxygen supply in an emergency is provided, ensuring that the gas source can be quickly cut off during maintenance or failure to avoid dangerous situations. It is usually linked with the control system and automatically shuts down when abnormal conditions (such as overpressure) are detected, further ensuring the safe operation of the system. By setting up multiple pressure gauges (pressure gauges one, two, and three), the pressure state of oxygen can be monitored in real time at different locations. This helps to promptly detect and deal with pressure fluctuations and ensure stable operation of the system. It is used to adjust and control the pressure of oxygen entering the subsequent pipeline to ensure that it meets process requirements, while protecting downstream equipment from excessive pressure, removing impurities and particulate matter in the oxygen to prevent these substances from clogging the pipeline or damaging sensitive equipment, thereby extending the service life of the entire system and maintaining the purity of the gas. Through the configuration of the above components, operators can more conveniently perform daily inspections and regular maintenance work.

[0011] Furthermore, the oxygen injection branch of the oxygen lance in the first heating section also includes a second safety shut-off valve, a first flow meter, a first flow control valve, a fourth pressure gauge and an oxygen lance. The second safety shut-off valve, the first flow meter, the first flow control valve, the fourth pressure gauge and the oxygen lance are connected in sequence through a pipeline, and a plurality of oxygen lances are provided.

[0012] By adopting the above technical solution, the second safety shut-off valve is linked with the control system, and can be quickly closed when abnormal conditions (such as overpressure or leakage) are detected to prevent safety accidents caused by oxygen leakage. By setting the safety shut-off valve, the oxygen supply can be quickly isolated in an emergency to ensure the safety of the operator. The flow meter 1 = monitors the oxygen flow through the pipeline in real time, providing accurate data feedback to the operator for timely adjustment. The flow control valve 1 = adjusts the flow of oxygen as needed to ensure that the amount of oxygen entering the heating furnace meets the process requirements. This helps to optimize the combustion process and improve thermal efficiency. The pressure gauge 4 continuously monitors the pressure state of oxygen to ensure that it is within a safe and suitable range for combustion. This is crucial to maintaining the stable operation of the system. Each oxygen gun can independently deliver oxygen to different areas of the heating furnace to achieve uniform distribution of oxygen. This ensures that the temperature of the entire heating section is more uniform and improves the heating quality and efficiency.

[0013] Furthermore, the main oxygen-enriched branch also includes a safety shut-off valve three, a flow meter two, a flow control valve two, a pressure gauge five, a manual shut-off valve two and a pressure gauge six. The safety shut-off valve three, the flow meter two, the flow control valve two, the pressure gauge five, the manual shut-off valve two and the pressure gauge six are connected in sequence through pipelines. One end of the oxygen-enriched distributor is connected to the pressure gauge six and the other end is connected to the main pipeline.

[0014] By adopting the above technical solution, the safety shut-off valve 3 can be automatically closed when an abnormal situation (such as overpressure or leakage) is detected to prevent safety accidents caused by oxygen leakage. The manual shut-off valve 2 provides a means of manually isolating the oxygen supply, which can quickly cut off the gas source in an emergency or maintenance to ensure the safety of the operator. The flow meter 2 monitors the oxygen flow through the pipeline in real time and provides accurate data feedback to the operator for timely adjustment. The flow control valve 2 adjusts the oxygen flow as needed to ensure that the amount of oxygen entering the main pipeline meets the process requirements. This helps to optimize the combustion process and improve thermal efficiency. Pressure gauges 5 and 6: Continuously monitor the pressure state of oxygen at different positions to ensure that it is within a safe and suitable range for combustion. This is crucial to maintaining the stable operation of the system. By monitoring multiple pressure points, the pressure distribution of the entire system can be more accurately grasped, and potential problems can be discovered and handled in a timely manner. The oxygen-enriched distributor evenly distributes the pressure-regulated oxygen into the main pipeline and mixes it with the combustion-supporting air to achieve oxygen-enriched combustion throughout the furnace. This can ensure a more uniform distribution of oxygen throughout the heating furnace, improve combustion efficiency and temperature consistency. By adjusting the flow control valve, the oxygen supply can be flexibly adjusted according to actual needs to meet different production conditions and process requirements. The design of the oxygen-enriched distributor enables the system to better adapt to different types of heating furnaces and fuel types, improving the versatility and adaptability of the system.

[0015] Furthermore, two oxygen lances are arranged on both sides of the burner, with each burner being provided with two oxygen lances.

[0016] By adopting the above technical solution, more complete combustion can be achieved through high-speed jet entrainment combustion of the oxygen lance. The oxygen-rich environment is conducive to the complete combustion of the fuel, thereby improving the thermal efficiency. An oxygen lance is configured on each side of each burner to ensure a more uniform distribution of oxygen, further improving the combustion effect. The double oxygen lance design can provide a more stable oxygen supply. Even if one of the oxygen lances fails or is blocked, the other oxygen lance can continue to work, ensuring the continuity and stability of the combustion process. Due to the uniform distribution of oxygen, a more uniform high-temperature area can be formed around the burner, which is particularly important for heating processes that require precise temperature control. Uniform oxygen supply helps to reduce local overheating or underheating and improve the temperature uniformity of the entire heating furnace. By independently controlling the flow of each oxygen lance, the oxygen supply at different positions can be adjusted according to actual needs to meet the heating requirements under specific process conditions, providing higher operational flexibility, so that the system can adapt to different production requirements and process changes.

[0017] The present invention also includes a full oxygen combustion method applicable to a heating furnace, using a full oxygen combustion system applicable to a heating furnace to achieve oxygen-enriched combustion of the entire heating furnace, the oxygen source first passes through the oxygen pressure regulating branch to distribute oxygen to the first heating section oxygen lance oxygen branch or the main oxygen-enriched branch, when the first heating section oxygen lance oxygen branch is opened, the safety cut-off valve three is closed to close the main oxygen-enriched branch, the oxygen pressure is regulated and the temperature is detected in the first heating section oxygen lance oxygen branch, and then the oxygen is transported to the heating furnace; when the main oxygen-enriched branch is opened, the safety cut-off valve two is closed, and the oxygen in the main oxygen-enriched branch is transmitted to the main pipeline through the oxygen-enriched distributor. .

[0018] Furthermore, in the oxygen pressure regulating branch, the oxygen pressure is adjusted to not more than 0.5MPa, the pressure-regulated oxygen passes through the pressure transmitter and the temperature transmitter to detect the pressure and temperature of the oxygen respectively, then the flow control valve 1 is opened to control the oxygen flow, the oxygen flow is observed through the flow meter 1, and finally the oxygen is transmitted to the heating furnace through the oxygen gun, at this time, the regenerative burner does not reverse, and the staggered burner combustion mode equipped with the oxygen gun on the opposite side of the heating furnace is enabled. .

[0019] Furthermore, in the main oxygen-enriched branch, when pressure gauge 6 shows that the oxygen pressure does not exceed 0.3 MPa, oxygen is discharged through the oxygen-enriched distributor.

[0020] The present invention has the following beneficial effects:

[0021] 1. The present invention can make the fuel burn more completely by increasing the oxygen concentration, thereby improving the thermal efficiency, reducing the unburned fuel, and reducing the pollutant emission. The pressure, temperature and flow rate of oxygen can be accurately adjusted by using the pressure transmitter, temperature transmitter and flow control valve and other components in the pressure regulating branch to ensure that the amount of oxygen entering the heating furnace meets the process requirements, further optimize the combustion process, and evenly distribute the oxygen into the main pipeline through the oxygen-enriched distributor and mix it with the combustion-supporting air to achieve oxygen-enriched combustion in the whole furnace, ensure that the oxygen distribution in the whole heating furnace is more uniform, and improve the combustion efficiency and temperature consistency;

[0022] 2. The present invention provides safety shut-off valves and manual shut-off valves in the oxygen pressure regulating branch, the first heating section oxygen lance oxygen injection branch and the main oxygen enrichment branch, which can be quickly closed when abnormal conditions (such as overpressure or leakage) are detected to prevent safety accidents caused by oxygen leakage. Through multiple pressure gauges (pressure gauges 1 to 6) and flow meters (flow meters 1 and 2), the pressure and flow state of oxygen can be monitored in real time, potential problems can be discovered and handled in time, and the stable operation of the system can be ensured;

[0023] 3. The present invention can form a more uniform high-temperature area around the burner by evenly distributing oxygen, reduce local overheating or underheating, and improve the temperature uniformity of the entire heating furnace. This is particularly important for heating processes that require precise temperature control. The system allows the selection of local (first heating section) or full-furnace oxygen-enriched combustion modes according to actual needs, providing greater operational flexibility. For example, when it is necessary to emphasize the heating effect of a certain area, the local mode can be selected, and when it is hoped to improve the heating efficiency as a whole, it can be switched to the full-furnace mode. The design of the oxygen-enriched distributor enables the system to better adapt to different types of heating furnaces and fuel types, improves the versatility and adaptability of the system, and meets different production conditions and process requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the system structure of the present invention.

[0025] Among them, 1-manual shut-off valve 1; 2-pressure gauge 1; 3-filter; 4-pressure gauge 2; 5-pressure regulating valve; 6-pressure gauge 3; 7-safety shut-off valve 1; 8-pressure transmitter; 9-temperature transmitter; 10-safety shut-off valve 2; 11-flow meter 1; 12-flow control valve 1; 13-pressure gauge 4; 14-oxygen gun; 15-safety shut-off valve 3; 16-flow meter 2; 17-flow control valve 2; 18-pressure gauge 5; 19-manual shut-off valve 2; 20-pressure gauge 6; 21-oxygen enriched distributor. DETAILED DESCRIPTION

[0026] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific preferred embodiments.

[0027] In the description of the present invention, it should be understood that the terms "left side", "right side", "upper part", "lower part" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. "First", "second" and the like do not indicate the importance of the components, and therefore cannot be understood as limiting the present invention. The specific dimensions used in this embodiment are only for illustrating the technical solution, and do not limit the scope of protection of the present invention.

[0028] like Figure 1As shown, an oxygen-enriched combustion system for a coal gas single regenerative heating furnace includes an oxygen pressure regulating branch, a first heating section oxygen lance oxygen injection branch, and a main oxygen-enriched branch. The oxygen pressure regulating branch is responsible for regulating and controlling the oxygen pressure and temperature detection entering the system, and its components include a manual shut-off valve 1 for manually cutting off the oxygen supply in an emergency, a pressure gauge 2 for monitoring the pressure of the oxygen source, a filter 3 for removing impurities and particulate matter in the oxygen, a pressure gauge 2 4 for monitoring the pressure of the filtered oxygen, a pressure regulating valve 5 for adjusting the pressure of the oxygen to the required level, a pressure gauge 3 6 for monitoring the pressure of the oxygen after pressure regulation, a safety shut-off valve 7 for automatically closing when an abnormality is detected to ensure safety, and a pressure transmitter and a temperature transmitter 9 for respectively detecting and transmitting the pressure and temperature data of the oxygen. The oxygen lance oxygen branch of the first heating section performs full oxygen combustion in a local area (the first heating section, and its components include a safety shut-off valve 2 10 that automatically closes when an abnormal situation is detected to ensure safety, a flow meter 11 that monitors the oxygen flow in the pipeline, a flow control valve 12 that adjusts the oxygen flow into the heating furnace, and a pressure gauge 4 13 that monitors the oxygen pressure before entering the heating furnace. Multiple oxygen lances 14 directly deliver oxygen into the heating furnace, and each burner is equipped with two oxygen lances to ensure uniform oxygen distribution, thereby improving combustion efficiency and stability. The main oxygen-enriched branch performs oxygen-enriched combustion throughout the furnace, and its components include a safety shut-off valve 3 15 that automatically closes when an abnormal situation is detected to ensure safety, a flow meter 2 16 that monitors the oxygen flow into the main pipeline, a flow control valve 2 17 that adjusts the oxygen flow into the main pipeline, a pressure gauge 5 18 that monitors the oxygen pressure before entering the main pipeline, a manual shut-off valve 2 19 that is used to manually cut off the oxygen supply in an emergency, and a pressure gauge 6 20 that monitors The oxygen pressure in the main pipeline, the oxygen-enriched distributor 21 evenly distributes the oxygen after pressure regulation to the main pipeline, mixes it with the combustion-supporting air, and realizes oxygen-enriched combustion in the whole furnace. In terms of working mode switching, when it is necessary to carry out local full oxygen combustion in the first heating section, close the main oxygen-enriched branch, and open the oxygen-shooting branch of the oxygen gun in the first heating section; when it is necessary to carry out oxygen-enriched combustion in the whole heating furnace, close the oxygen-shooting branch of the oxygen gun in the first heating section, and open the main oxygen-enriched branch. The structural advantage of this system is that it ensures that the system can quickly isolate the oxygen supply under abnormal circumstances through multiple safety shut-off valves and manual shut-off valves, and uses pressure regulating valves, flow control valves and various pressure gauges to achieve precise control of oxygen pressure, temperature and flow. It provides greater operational flexibility by selecting oxygen-enriched combustion modes in the local or whole furnace range according to actual needs. The design of oxygen-enriched distributors and multiple oxygen guns ensures the uniform distribution of oxygen in the heating furnace, improving combustion efficiency and temperature consistency.

[0029] A full oxygen combustion method suitable for a heating furnace, wherein the oxygen source is first pressure-regulated and temperature-regulated through an oxygen pressure regulating branch; when the mode is switched, when the oxygen lance oxygen-emitting branch of the first heating section is opened, the safety shut-off valve three 15 is closed to close the main oxygen-enriched branch, and when the main oxygen-enriched branch is opened, the safety shut-off valve two 10 is closed; in the operation of the oxygen lance oxygen-emitting branch of the first heating section, the oxygen is pressure-regulated and the temperature is detected, the oxygen flow is controlled by a flow control valve one 12, and the oxygen flow is observed by a safety shut-off valve two 11 to ensure that the oxygen flow is 4000 Nm3 / h, and the regulated oxygen is delivered to the heating furnace through an oxygen lance 14, at which time, the regenerative burner is not reversed, and the staggered burner combustion mode equipped with an oxygen lance on the opposite side of the heating furnace is enabled to ensure uniform heating; in the operation of the main oxygen-enriched branch, when the pressure gauge six 20 shows that the oxygen pressure is 0.3 MPa, the oxygen is discharged through an oxygen-enriched distributor 21, and the oxygen is evenly distributed to the main pipeline through the oxygen-enriched distributor 21, and mixed with the combustion-supporting air to achieve oxygen-enriched combustion in the entire furnace. The full oxygen combustion method realizes an efficient, safe and flexible oxygen-enriched combustion process through a sophisticated control system, and its specific advantages include: through multiple safety shut-off valves (such as safety shut-off valve 17, safety shut-off valve 2 10, safety shut-off valve 3 15) and manual shut-off valves (manual shut-off valve 1 and manual shut-off valve 2 19), it ensures that the oxygen supply can be quickly isolated under abnormal circumstances; by using the pressure regulating valve 5, flow control valve 12 and flow control valve 2 17 and a variety of pressure gauges (such as pressure gauge 1 2 to pressure gauge 6 20), it realizes precise control of oxygen pressure, temperature and flow; according to actual needs, the oxygen-enriched combustion mode can be selected locally (first heating section) or in the whole furnace, providing greater operational flexibility; through the design of the oxygen-enriched distributor 21 and multiple oxygen guns, it ensures the uniform distribution of oxygen in the heating furnace, and improves the combustion efficiency and temperature consistency.

[0030] The coal gas single regenerative heating furnace is generally divided into the first heating section, the second heating section, the third heating section and the equalizing section. The billet is pushed along the furnace of the heating furnace. The oxygen passes through the manual shut-off valve 1 and then the pressure is measured by the pressure gauge 2. After the pressure is measured, the oxygen passes through the filter 3 to remove impurities and then enters the pressure regulating valve 5 to adjust the pressure to an appropriate pressure. Pressure gauges 2 4 and 3 6 are respectively set before and after the regulating valve 5. The oxygen after pressure adjustment passes through the safety shut-off valve 7. The pressure transmitter 8 and the temperature transmitter 9 are installed after the safety shut-off valve 7. In the oxygen lance oxygen injection mode, the first heating section is fully oxygen-burned, the safety shut-off valve 3 15 is closed, the oxygen is measured by the safety shut-off valve 2 10 and the flow meter 11, and the flow control valve 12 adjusts the flow and then enters the oxygen lance 14 through the pressure gauge 4 13 and is sent to the interior of the heating furnace. Here, the gas and oxygen are non-premixed for combustion to achieve efficient energy conversion. The full oxygen combustion in the first heating section can greatly increase the flame temperature, and the ratio of triatomic and polyatomic gases increases. The increase in the flame temperature of the slab in the first heating section and the increase in the blackness of the smoke greatly shorten the heating time and the time in the furnace, which can greatly increase the output of the heating furnace, and save energy while achieving increased production. In the oxygen-enriched mode of the main pipe, the safety shut-off valve 2 10 is closed, and the oxygen enters the flow meter 2 16 through the safety shut-off valve 3 15 to measure the flow, and then the flow is adjusted by the flow control valve 2 17, and then enters the oxygen-enriched distributor 21 after the manual shut-off valve 2 19 to be sent to the main pipeline to be fully mixed with the air. The pressure gauge 5 18 and the pressure gauge 6 20 are respectively set before and after the manual shut-off valve 2 19. The oxygen flow is automatically controlled in the oxygen-enriched mode of the main pipe. After the air volume signal in the main oxygen-enriched mode is connected to the system, automatic operation is achieved by setting the oxygen flow or oxygen enrichment;

[0031] Taking a walking beam single regenerative heating furnace, the fuel is high coke mixed gas with a calorific value of about 1800Kcal / Nm3 as an example, the heating furnace is divided into the first heating section, the second heating section, the third heating section and the soaking section. The oxygen pipeline of the heating furnace is connected to the valve group of the oxygen-enriched branch (maximum flow rate 4000Nm3 / h). The oxygen-enriched valve group is designed with two branches, and the two branches are used for flow metering and automatic control respectively. The two branches do not work at the same time, but can be switched to realize oxygen-enriched combustion in the main pipe oxygen-enriched mode and the oxygen-gun oxygen-injection mode. In the oxygen-gun oxygen-injection mode, the regenerative burner of the first heating section does not reverse, and the combustion method of 14 burners on the opposite side of the heating furnace is enabled. Each burner is equipped with two oxygen guns to realize full oxygen combustion in the first heating section; in the main pipe oxygen-enriched mode, another branch pipe (maximum flow rate 4000Nm3 / h) is sent to the combustion-supporting air main pipe for mixing to realize oxygen-enriched combustion of the whole furnace.

[0032] The preferred embodiments of the present invention are described in detail above; however, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, various equivalent transformations can be made to the technical solutions of the present invention, and these equivalent transformations all belong to the protection scope of the present invention.

Claims

1. An oxygen-enriched combustion system for a gas-fired single regenerative heating furnace, characterized in that: The invention comprises an oxygen pressure regulating branch, a first heating section oxygen lance oxygen emitting branch and a main oxygen-enriched branch. The oxygen pressure regulating branch is provided with a pressure transmitter and a temperature transmitter (9). The oxygen source is connected to the oxygen pressure regulating branch through a pipeline. The oxygen flows into the first heating section oxygen lance oxygen emitting branch or the main oxygen-enriched branch after pressure regulation. When the first heating section oxygen lance oxygen emitting branch is started, the main oxygen-enriched branch is closed. After the oxygen flow is adjusted in the first heating section oxygen lance oxygen emitting branch, the oxygen is sent to the heating furnace. When the main oxygen-enriched branch is started, the first heating section oxygen lance oxygen emitting branch is closed, and the enriched oxygen is sent to the main pipeline through the oxygen-enriched distributor (21).

2. The oxygen-enriched combustion system for a gas-fired single regenerative heating furnace according to claim 1, characterized in that: The oxygen pressure regulating branch circuit further comprises a manual shut-off valve (1), a pressure gauge (2), a filter (3), a pressure gauge (4), a pressure regulating valve (5), a pressure gauge (6) and a safety shut-off valve (7); the manual shut-off valve (1), the pressure gauge (2), the filter (3), the pressure gauge (4), the pressure regulating valve (5), the pressure gauge (6) and the safety shut-off valve (7) are connected in sequence through a pipeline.

3. The oxygen-enriched combustion system for a gas-fired single regenerative heating furnace according to claim 1, characterized in that: The oxygen injection branch of the oxygen lance of the first heating section further comprises a second safety shut-off valve (10), a first flow meter (11), a first flow control valve (12), a fourth pressure gauge (13) and an oxygen lance (14); the second safety shut-off valve (10), the first flow meter (11), the first flow control valve (12), the fourth pressure gauge (13) and the oxygen lance (14) are connected in sequence through a pipeline, and a plurality of oxygen lances (14) are provided.

4. The oxygen-enriched combustion system for a gas-fired single regenerative heating furnace according to claim 1, characterized in that: The main oxygen-enriched branch line also includes a safety shut-off valve three (15), a flow meter two (16), a flow control valve two (17), a pressure gauge five (18), a manual shut-off valve two (19) and a pressure gauge six (20). The safety shut-off valve three (15), the flow meter two (16), the flow control valve two (17), the pressure gauge five (18), the manual shut-off valve two (19) and the pressure gauge six (20) are connected in sequence through pipelines. One end of the oxygen-enriched distributor (21) is connected to the pressure gauge six (20) and the other end is connected to the main pipeline.

5. The oxygen-enriched combustion system for a gas-fired single regenerative heating furnace according to claim 3, characterized in that: The oxygen lances (14) are arranged on both sides of the burner, and each burner is arranged with two oxygen lances (14).

6. A full oxygen combustion method suitable for a heating furnace, characterized in that: By using the oxygen-enriched combustion system for a single-gas regenerative heating furnace as described in any one of claims 1 to 5, oxygen-enriched combustion is achieved in the entire heating furnace. The oxygen source first passes through the oxygen pressure regulating branch to distribute oxygen to the first heating section oxygen lance oxygen-emitting branch or the main oxygen-enriched branch. When the first heating section oxygen lance oxygen-emitting branch is opened, the safety shut-off valve three (15) is closed to close the main oxygen-enriched branch. The oxygen is pressure-regulated and temperature-detected in the first heating section oxygen lance oxygen-emitting branch, and then the oxygen is transported to the heating furnace. When the main oxygen-enriched branch is opened, the safety shut-off valve two (10) is closed, and the oxygen in the main oxygen-enriched branch is transmitted to the main pipeline through the oxygen-enriched distributor (21).

7. The oxyfuel combustion method suitable for a heating furnace according to claim 6, characterized in that: In the oxygen pressure regulating branch, the oxygen pressure is adjusted to not more than 0.5 MPa. The pressure-regulated oxygen passes through the pressure transmitter and the temperature transmitter (9) to detect the pressure and temperature of the oxygen respectively. Then, the flow control valve 1 (12) is opened to control the oxygen flow. The oxygen flow is observed through the safety cut-off valve 2 (11). Finally, the oxygen is transmitted to the heating furnace through the oxygen gun (14). At this time, the regenerative burner does not reverse, and the staggered burner combustion mode equipped with the oxygen gun on the opposite side of the heating furnace is enabled.

8. The oxyfuel combustion method applicable to a heating furnace according to claim 6, characterized in that: In the main oxygen-enriched branch, when the pressure gauge 6 (20) shows that the oxygen pressure does not exceed 0.3 MPa, the oxygen is discharged through the oxygen-enriched distributor (21).

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