A heating furnace oxygen-enriched combustion system and a control method thereof

Abstract

The application provides a heating furnace oxygen-enriched combustion system and a control method thereof. The oxygen-enriched combustion system comprises a heating furnace, a low-calorific-value gas main pipe, a high-calorific-value gas pipeline, an oxygen main pipe and an air pipeline. The outlet end of the oxygen main pipe is branched into a plurality of oxygen branch pipes. One of the oxygen branch pipes is connected with the air pipeline to form a mixed oxygen main pipe. The mixed oxygen main pipe is further connected with a furnace top heating section and a furnace wall heating section. The remaining oxygen branch pipes are directly connected with side heating sections. The outlet end of the low-calorific-value gas main pipe is branched into a plurality of low-calorific-value gas branch pipes. One of the low-calorific-value gas branch pipes is connected with the high-calorific-value gas pipeline to form a mixed gas pipeline. The mixed gas pipeline is further connected with the furnace top heating section. The remaining low-calorific-value gas branch pipes are directly connected with the furnace wall heating section. The application improves the regulation and flexibility of temperature regulation of each heating section of the heating furnace, and is beneficial to fully exert the technical advantages of oxygen-enriched combustion, and maximally save fuel and reduce production cost.

Description

Technical Field

[0001] This invention relates to the field of furnaces and kilns in the metallurgical industry, and specifically to an oxygen-enriched combustion system for a heating furnace and its control method. Background Technology

[0002] Metallurgical furnaces are crucial processes in the steel industry. Energy conservation, emission reduction, and cost reduction in industrial furnaces have been key research areas in recent years. While oxy-fuel combustion technology has wide applications in industrial combustion, its use in steel industry heating furnaces is relatively limited. This is primarily because conventional oxy-fuel combustion technology is not economically viable in steel heating furnaces, and the fuel cost savings cannot offset the increased oxygen consumption costs. Given my country's large steel production and the availability of various calorific values ​​of coal gas and oxygen in steel enterprises, developing an oxy-fuel combustion system suitable for steel heating furnaces, tailored to the steel production process and fully utilizing existing energy resources, is urgently needed and has a very broad market prospect. Summary of the Invention

[0003] The objective of this invention is to provide an oxygen-enriched combustion system for a heating furnace, which improves the adjustability and flexibility of burner temperature regulation in each heating section of the furnace, thereby maximizing the technical advantages of oxygen-enriched combustion and maximizing fuel savings and reducing production costs.

[0004] An oxygen-enriched combustion system for a heating furnace includes a heating furnace, a low-calorific-value gas main pipe, a high-calorific-value gas pipeline, an oxygen main pipe, and an air pipeline;

[0005] The calorific value of the gas in the low-calorific-value gas main is lower than that in the high-calorific-value gas main.

[0006] The furnace top heating section is equipped with furnace top heating section burners;

[0007] The furnace wall heating section of the heating furnace is equipped with side heating section burners;

[0008] One end of the oxygen main pipe is an oxygen inlet, and the other end is connected to multiple oxygen branch pipes. One of the oxygen branch pipes intersects with the air pipeline to form a mixed oxygen main pipe. The mixed oxygen main pipe is then connected to multiple mixed oxygen branch pipes, which are then connected to the burners in the furnace top heating section and the side heating section, respectively. The remaining oxygen branch pipes are directly connected to the burners in the side heating section.

[0009] One of the oxygen branches is equipped with an oxygen mixing valve, and the other oxygen branches are respectively equipped with corresponding oxygen valves.

[0010] One end of the low-calorific-value gas main is a low-calorific-value gas inlet, and the other end is connected to multiple low-calorific-value gas branch pipes. One of the low-calorific-value gas branch pipes intersects with a high-calorific-value gas pipeline to form a mixed gas pipeline. The mixed gas pipeline is then connected to the burners in the furnace top heating section. The remaining low-calorific-value gas branch pipes are directly connected to the corresponding burners in the side heating section.

[0011] The high-calorific-value gas pipeline is equipped with a high-calorific-value gas valve.

[0012] The oxygen-enriched combustion system of the heating furnace of the present invention, in addition to the existing configuration where "mixed oxygen pipes are connected one-to-one with the burners in the top heating section and the side heating section, and low-calorific-value gas pipes are connected one-to-one with the burners in the top heating section and the side heating section," also includes "oxygen pipes directly connected to the burners in the side heating section" and "high-calorific-value gas pipelines connected to the burners in the top heating section." This allows the top heating section to simultaneously have a "basic heating module" composed of "oxygen-enriched air" (composed of air and oxygen) + "low-calorific-value gas," and a heating module supplied by the "high-calorific-value gas pipeline." The "high-calorific-value gas enhanced heating module" of the furnace top heating section achieves the furnace temperature setpoint through the "basic heating module" and the "high-calorific-value gas enhanced heating module". Similarly, the furnace wall heating section also has a "basic heating module" composed of "oxygen-enriched air composed of air and oxygen" + "low-calorific-value gas" and an "oxygen enhanced heating module" supplied by "the remaining oxygen pipes". In other words, the furnace wall heating section achieves the furnace temperature setpoint through the "basic heating module" and the "oxygen enhanced heating module".

[0013] Furthermore, since the structures of the burners in the top heating section and the side heating section of the heating furnace are different, the burners in the top heating section generally use flat flame burners, and their working principle is: the gas and the combustion-supporting gas rotate, mix, and burn within the burner brick, forming a rotating, wall-attached disc-shaped flame at the furnace top; therefore, the top heating section of this invention uses controlled supply of high-calorific-value gas to enhance heating and achieve furnace temperature, avoiding the problem of uneven oxygen mixing and low oxygen utilization when pure oxygen is directly introduced; at the same time, since the furnace wall heating section does not have the problem of uneven oxygen mixing entering the burners in the top heating section, this invention uses controlled oxygen supply to enhance heating and achieve furnace temperature, resulting in high oxygen utilization and reducing the requirements of the furnace wall heating section on the calorific value of the gas, thus minimizing the use of coke oven gas and natural gas in the low-calorific-value gas. Additionally, since the unit price of oxygen is much lower than that of coke oven gas and natural gas, it helps to minimize costs.

[0014] The oxygen-enriched combustion system of the heating furnace of the present invention enables the burners in each heating section of the heating furnace to achieve the maximum degree of complete combustion, which is conducive to maximizing fuel savings and reducing production costs.

[0015] Furthermore, the number of furnace wall heating sections is at least two, and each furnace wall heating section is connected to a corresponding remaining oxygen branch pipe. Even further, the number of side heating section burners corresponding to each furnace wall heating section is at least two.

[0016] Furthermore, each of the aforementioned mixed oxygen pipes is equipped with a corresponding mixed oxygen valve, through which the mixed oxygen flow rate of the burners in the furnace top heating section and the side heating section can be flexibly adjusted.

[0017] Furthermore, one of the low-calorific-value gas pipes is equipped with a gas mixing valve. Through the gas mixing valve, the mixing ratio of low-calorific-value gas and high-calorific-value gas, as well as the calorific value of the gas in the furnace top heating section, can be adjusted more flexibly, accurately, and effectively with the high-calorific-value gas valve.

[0018] Furthermore, each of the remaining low-calorific-value gas pipes is equipped with a corresponding low-calorific-value gas valve. The low-calorific-value gas flow rate of the burners in the top heating section and the side heating section can be flexibly adjusted through the low-calorific-value gas valve and the mixed gas valve.

[0019] The second objective of this invention is to provide a control method for the oxygen-enriched combustion system described in the first objective of this invention, comprising the following steps:

[0020] (1) First open the oxygen mixing valve, close the oxygen valve, and adjust the oxygen mixing valve to the maximum opening. Let the oxygen-enriched gas formed by mixing oxygen and air pass through the main oxygen mixing pipe and each oxygen mixing branch pipe in sequence, and be sent into the heating furnace from the burners of the furnace top heating section and the burners of the side heating section to provide oxygen-enriched gas for the furnace top heating section and the furnace wall heating section, so that the oxygen concentration of the furnace top heating section and the furnace wall heating section is 21-28% and remains stable.

[0021] At the same time, the high-calorific-value gas valve is closed, allowing the low-calorific-value gas to pass sequentially through the low-calorific-value gas main pipe and each low-calorific-value gas branch pipe, and then be sent into the heating furnace from the burners of the furnace top heating section and the side heating section to provide gas calorific value for the furnace top heating section and the furnace wall heating section.

[0022] (2) When the furnace temperature of the furnace top heating section under step (1) is lower than the set furnace temperature of the furnace, open the oxygen valve and control the oxygen flow of the remaining oxygen pipes by adjusting the oxygen valve, so that the furnace temperature of the furnace top heating section of the furnace rises to the set furnace temperature of the furnace.

[0023] At the same time, when the furnace temperature of the furnace wall heating section of the heating furnace is lower than the set furnace temperature of the heating furnace under step (1), the high calorific value gas valve is opened, and the calorific value of the gas in the mixed gas pipeline is controlled by adjusting the high calorific value gas valve; so that the furnace temperature of the furnace wall heating section of the heating furnace is raised to the set furnace temperature for heating.

[0024] This invention employs different oxygen enrichment methods and different calorific value gases for the burners in the top heating section and the side heating section of the heating furnace. Furthermore, the furnace temperature in the top heating section is controlled by adjusting the flow rate of the mixed gas and the flow rate of the high-calorific-value gas, while the furnace temperature in the side heating section is controlled by adjusting the flow rate of the mixed gas and the flow rate of oxygen directly supplied to the burners. This allows for precise and flexible control of the burners in each heating section, maximizing combustion and optimizing cost savings. Ultimately, this achieves the effect of maximizing fuel savings and reducing production costs.

[0025] Furthermore, the oxygen concentration in the furnace top heating section and the furnace wall heating section obtained in step (1) is the same.

[0026] Furthermore, the calorific value of the gas obtained in step (1) for the furnace top heating section and the furnace wall heating section is the same.

[0027] Furthermore, when the furnace temperature of the heating section of the furnace wall under step (2) is higher than the set furnace temperature, the opening of the oxygen valve is reduced first. When the opening of the oxygen valve is zero, but the furnace temperature of the heating section of the furnace wall is still higher than the set furnace temperature, the opening of the oxygen mixing valve is reduced again until the furnace temperature of the heating section of the furnace wall drops to the set furnace temperature.

[0028] Furthermore, when the furnace temperature of the top heating section of the heating furnace under step (2) is higher than the set furnace temperature of the heating furnace, first reduce the opening of the high calorific value gas valve. When the opening of the high calorific value gas valve is zero, but the furnace temperature of the top heating section of the heating furnace is still higher than the set furnace temperature of the heating furnace, then reduce the opening of the mixed gas valve and the low calorific value gas valve until the furnace temperature of the top heating section of the heating furnace drops to the set furnace temperature of the heating furnace. Attached Figure Description

[0029] Figure 1 This is a simplified diagram of the oxygen-enriched combustion system of the heating furnace of the present invention. Detailed Implementation

[0030] The specific implementation of the oxygen-enriched combustion system and control method for the heating furnace of the present invention will be described below. Example 1

[0031] The furnace temperature is set to 1150–1250℃.

[0032] like Figure 1As shown, the oxygen-enriched combustion system of the heating furnace in Example 1 includes a heating furnace 1, a low-calorific-value gas main pipe 2, a high-calorific-value gas pipeline 3, an oxygen main pipe 4, and an air pipeline 5.

[0033] A furnace top heating section burner 14 is provided in the furnace top heating section 11 of the heating furnace 1;

[0034] A corresponding side heating section burner (15, 16) is provided in the furnace wall heating section (12, 13) of the heating furnace 1.

[0035] One end of the oxygen main pipe 4 is an oxygen inlet, and the other end is branched into multiple oxygen branch pipes (41, 43, 45). One of the oxygen branch pipes 41 intersects with the air pipe 5 to form a mixed oxygen main pipe 541. The mixed oxygen main pipe 541 is then branched into multiple mixed oxygen branch pipes (51, 53, 55). The multiple mixed oxygen branch pipes (51, 53, 55) are then connected to the burners 14 in the furnace top heating section and the burners (15, 16) in the side heating section, respectively. The remaining oxygen branch pipes (43, 45) are directly connected to the burners (15, 16) in the side heating section.

[0036] One of the oxygen branch pipes 41 is equipped with an oxygen mixing valve 42, and the other oxygen branch pipes (43, 45) are respectively equipped with oxygen valves (44, 46).

[0037] One end of the low-calorific-value gas main pipe 2 is a low-calorific-value gas inlet, and the other end is connected to multiple low-calorific-value gas branch pipes (21, 23, 25). One of the low-calorific-value gas branch pipes 25 intersects with the high-calorific-value gas pipeline 3 to form a mixed gas pipeline 325. The mixed gas pipeline 325 is then connected to the burner 14 of the furnace top heating section. The other low-calorific-value gas branch pipes (21, 23) are directly connected to the burners (15, 16) of the side heating section.

[0038] The high-calorific-value gas pipeline 3 is equipped with a high-calorific-value gas valve 31.

[0039] The control method for the oxygen-enriched combustion system described in Example 1 includes the following steps:

[0040] (1) First open the oxygen mixing valve 42, close the oxygen valves (44, 46), and adjust the oxygen mixing valve 42 to the maximum opening, so that the oxygen-enriched gas formed by mixing oxygen and air passes through the mixed oxygen main pipe 541 and each mixed oxygen branch pipe (51, 53, 55) in sequence, and is sent into the heating furnace 1 from the burner 14 of the furnace top heating section and the burner (15, 16) of the side heating section, so as to provide oxygen-enriched gas for the furnace top heating section 11 and the furnace wall heating section (12, 13), so that the oxygen concentration of the furnace top heating section 11 and the furnace wall heating section (12, 13) is 21-28% and maintained stably;

[0041] At the same time, the high-calorific-value gas valve 31 is closed, allowing the low-calorific-value gas to pass sequentially through the low-calorific-value gas main pipe 2 and each low-calorific-value gas branch pipe (21, 23, 25), and be sent into the heating furnace 1 from the burner 14 of the furnace top heating section and the burners (15, 16) of the side heating section, to provide gas calorific value for the furnace top heating section 11 and the furnace wall heating section (12, 13);

[0042] (2) When the furnace temperature of the top heating section 11 of the heating furnace 1 is lower than the set furnace temperature of the heating furnace 1 under the operation of step (1) (i.e., the furnace temperature is lower than 1150℃), open the oxygen valves (44, 46) and control the oxygen flow of the remaining oxygen branches (43, 45) by adjusting the oxygen valves (44, 46) so that the furnace temperature of the top heating section 11 of the heating furnace 1 rises to the set furnace temperature (1150~1250℃).

[0043] At the same time, when the furnace temperature of the furnace wall heating section (12, 13) of the heating furnace 1 is lower than the set furnace temperature of the heating furnace 1 under the operation of step (1), the high calorific value gas valve 31 is opened, and the calorific value of the gas in the mixed gas pipeline 325 is controlled by adjusting the high calorific value gas valve 31; so that the furnace temperature of the furnace wall heating section (12, 13) of the heating furnace 1 is raised to the set furnace temperature of the heating furnace 1 (1150~1250℃).

[0044] Therefore, in the furnace combustion system and control method of Embodiment 1 of the present invention, the furnace top heating section and the furnace wall heating section, in addition to raising the furnace temperature by introducing "oxygen-enriched gas formed by mixing oxygen and air" and "low-calorific-value coal gas", further introduce "high-calorific-value coal gas" to raise the furnace temperature; while the furnace wall heating section introduces "oxygen" to further raise the furnace temperature.

[0045] Comparative Example 1

[0046] Under the same furnace production conditions as in Example 1, in the furnace combustion system and control method of Comparative Example 1, the furnace top heating section and furnace wall heating section both increase the furnace temperature by introducing "air" and "high-calorific-value gas".

[0047] Comparative Example 2

[0048] Under the same furnace production conditions as in Example 1, in the furnace combustion system and control method of Comparative Example 2, the furnace top heating section and furnace wall heating section both increase the furnace temperature by introducing "oxygen-enriched gas formed by mixing oxygen and air" and "medium-calorific-value coal gas".

[0049] The low-calorific-value gas and high-calorific-value gas mentioned in this invention are both mixed gases composed of blast furnace gas, coke oven gas and natural gas from steel enterprises. However, compared with the low-calorific-value gas, the high-calorific-value gas contains a higher proportion of coke oven gas and natural gas.

[0050] The combustion-supporting gas, oxygen concentration of the combustion-supporting gas, and total calorific value of the gas in the furnace top heating section 11 and furnace wall heating sections (12, 13) of the heating furnace 1 of Comparative Examples 1, 2 and 1 are shown in Table 1 below.

[0051] Table 1

[0052]

[0053] The applicant also provides cost calculations for Comparative Example 1, Comparative Example 2, and Example 1, as shown in Table 2 below.

[0054] Table 2

[0055]

[0056] As shown in Table 2, the oxygen-enriched combustion system and control method of the present invention (i.e., Example 1) employ different oxygen-enrichment methods and different calorific values ​​of gas for the furnace top heating section and the furnace wall heating section. Furthermore, the core of the furnace top heating section is to control the furnace temperature by controlling the supply of high-calorific-value gas, while the core of the furnace wall heating section is to control the furnace temperature by controlling the supply of oxygen. This ensures that the burners in each heating section can achieve the maximum degree of complete combustion, thereby optimizing cost savings and ultimately maximizing fuel savings and reducing production costs (total cost reduced to RMB 331.85 million / year, resulting in a benefit of RMB 21.1 million / year).

[0057] Of course, the furnace wall heating sections (12, 13) of the present invention may be, but are not limited to, two, and the number of side heating section burners (15, 16) corresponding to each furnace wall heating section (12, 13) may be, but is not limited to, the two shown in the figures. The number of furnace wall heating sections (12, 13) and the number of side heating section burners (15, 16) corresponding to each furnace wall heating section are determined by the model of the heating furnace. Each furnace wall heating section (12, 13) is connected to the remaining oxygen branch pipes (43, 45) in a one-to-one correspondence.

[0058] The oxygen-enriched combustion system of the heating furnace in Example 1 can be improved as follows:

[0059] (1) such as Figure 1 As shown, each of the mixed oxygen pipes (51, 53, 55) is equipped with a corresponding mixed oxygen valve (52, 54, 56), through which the mixed oxygen valves (52, 54, 56) can flexibly adjust the mixed oxygen flow rate of the burner 14 in the furnace top heating section and the burners (15, 16) in the side heating section.

[0060] (2) such as Figure 1As shown, one of the low-calorific-value gas pipes 25 is equipped with a gas mixing valve 26. Through the gas mixing valve 26, together with the high-calorific-value gas valve 31, the mixing ratio of low-calorific-value gas and high-calorific-value gas and the calorific value of the gas in the furnace top heating section can be adjusted more flexibly, accurately and effectively.

[0061] (3) such as Figure 1 As shown, each of the remaining low-calorific-value gas pipes (21, 23) is equipped with a corresponding low-calorific-value gas valve (22, 24). The low-calorific-value gas flow rate of the burners 14 in the furnace top heating section and the burners (15, 16) in the side heating section can be flexibly adjusted through the low-calorific-value gas valves (22, 24) and the gas mixing valve 26.

[0062] The oxygen concentrations of the furnace top heating section 11 and the furnace wall heating sections (15, 16) obtained in step (1) of the control method of the oxygen-enriched combustion system of the heating furnace in Example 1 are the same; similarly, the calorific value of the gas in the furnace top heating section and the furnace wall heating section obtained in step (1) are the same.

[0063] When the furnace temperature of the furnace wall heating section (15, 16) under the operation of step (2) of the control method of the oxygen-enriched combustion system of the heating furnace is higher than the set furnace temperature of the heating furnace 1 (i.e., the furnace temperature is higher than 1250℃), first reduce the opening of the oxygen valve (44, 46). When the opening of the oxygen valve (44, 46) is zero, but the furnace temperature of the furnace wall heating section (15, 16) is still higher than the set furnace temperature of the heating furnace, then reduce the opening of the oxygen mixing valve 42 until the furnace temperature of the furnace wall heating section (12, 13) drops to the set furnace temperature of the heating furnace (1150~1250℃).

[0064] When the furnace temperature of the top heating section 11 of the heating furnace is higher than the set furnace temperature of the heating furnace 1 under the operation of step (2) of the control method of the oxygen-enriched combustion system of the heating furnace (i.e., when the furnace temperature is higher than 1250℃), first reduce the opening of the high calorific value gas valve 31. When the opening of the high calorific value gas valve 31 is zero, but the furnace temperature of the top heating section 11 of the heating furnace is still higher than the set furnace temperature of the heating furnace 1, then reduce the opening of the mixed gas valve 26 and the low calorific value gas valves (22, 24) until the furnace temperature of the top heating section 11 of the heating furnace drops to the set furnace temperature of the heating furnace 1 (1150~1250℃).

[0065] For those skilled in the art, without departing from the concept of this invention, several simple deductions or substitutions can be made, and all such deductions or substitutions should be considered to fall within the scope of protection of this invention.

Claims

1. An oxygen-enriched combustion system for a heating furnace, comprising a heating furnace, a low-calorific-value gas main pipe, a high-calorific-value gas pipeline, an oxygen main pipe, and an air pipeline; The calorific value of the gas in the low-calorific-value gas main is lower than that in the high-calorific-value gas main. The furnace top heating section is equipped with furnace top heating section burners; The furnace wall heating section of the heating furnace is equipped with side heating section burners; characterized in that: One end of the oxygen main pipe is an oxygen inlet, and the other end is connected to multiple oxygen branch pipes. One of the oxygen branch pipes intersects with the air pipeline to form a mixed oxygen main pipe. The mixed oxygen main pipe is then connected to multiple mixed oxygen branch pipes, which are then connected to the burners in the furnace top heating section and the side heating section, respectively. The remaining oxygen branch pipes are directly connected to the burners in the side heating section. One of the oxygen branches is equipped with an oxygen mixing valve, and the other oxygen branches are respectively equipped with corresponding oxygen valves. One end of the low-calorific-value gas main is a low-calorific-value gas inlet, and the other end is connected to multiple low-calorific-value gas branch pipes. One of the low-calorific-value gas branch pipes intersects with a high-calorific-value gas pipeline to form a mixed gas pipeline. The mixed gas pipeline is then connected to the burners in the furnace top heating section. The remaining low-calorific-value gas branch pipes are directly connected to the corresponding burners in the side heating section. The high-calorific-value gas pipeline is equipped with a high-calorific-value gas valve.

2. The oxygen-enriched combustion system for the heating furnace according to claim 1, characterized in that: The number of furnace wall heating sections is greater than or equal to two, and each furnace wall heating section is connected to a corresponding other oxygen branch pipe.

3. The oxygen-enriched combustion system for the heating furnace according to claim 2, characterized in that: The number of burners in the side heating section corresponding to each of the furnace wall heating sections is ≥ two.

4. The oxygen-enriched combustion system for the heating furnace according to claim 1, characterized in that: Each of the aforementioned mixed oxygen pipes is equipped with a corresponding mixed oxygen valve.

5. The oxygen-enriched combustion system for the heating furnace according to claim 1, characterized in that: One of the low-calorific-value gas distribution pipes is equipped with a gas mixing valve.

6. The oxygen-enriched combustion system for a heating furnace according to claim 1, characterized in that: Each of the other low-calorific-value gas branch pipes is equipped with a corresponding low-calorific-value gas valve.

7. The control method for the oxygen-enriched combustion system of the heating furnace according to any one of claims 1 to 6, comprising the following steps: (1) First open the oxygen mixing valve, close the oxygen valve, and adjust the oxygen mixing valve to the maximum opening. Let the oxygen-enriched gas formed by mixing oxygen and air pass through the main oxygen mixing pipe and each oxygen mixing branch pipe in sequence, and be sent into the heating furnace from the burners of the furnace top heating section and the burners of the side heating section to provide oxygen-enriched gas for the furnace top heating section and the furnace wall heating section, so that the oxygen concentration of the furnace top heating section and the furnace wall heating section is 21-28% and remains stable. At the same time, the high-calorific-value gas valve is closed, allowing the low-calorific-value gas to pass sequentially through the low-calorific-value gas main pipe and each low-calorific-value gas branch pipe, and then be sent into the heating furnace from the burners of the furnace top heating section and the side heating section to provide gas calorific value for the furnace top heating section and the furnace wall heating section. (2) When the furnace temperature of the furnace top heating section under step (1) is lower than the set furnace temperature of the furnace, open the oxygen valve and control the oxygen flow of the remaining oxygen pipes by adjusting the oxygen valve, so that the furnace temperature of the furnace top heating section of the furnace rises to the set furnace temperature of the furnace. At the same time, when the furnace temperature of the furnace wall heating section of the heating furnace is lower than the set furnace temperature of the heating furnace under step (1), the high calorific value gas valve is opened, and the calorific value of the gas in the mixed gas pipeline is controlled by adjusting the high calorific value gas valve; so that the furnace temperature of the furnace wall heating section of the heating furnace is raised to the set furnace temperature for heating.

8. The control method for the oxygen-enriched combustion system of the heating furnace according to claim 7, characterized in that: The oxygen concentrations of the furnace top heating section and the furnace wall heating section obtained in step (1) are the same; the calorific value of the gas in the furnace top heating section and the furnace wall heating section obtained in step (1) is the same.

9. The control method for the oxygen-enriched combustion system of the heating furnace according to claim 7, characterized in that: When the furnace temperature of the heating section of the furnace wall under step (2) is higher than the set furnace temperature, first reduce the opening of the oxygen valve. When the opening of the oxygen valve is zero, but the furnace temperature of the heating section of the furnace wall is still higher than the set furnace temperature, then reduce the opening of the oxygen mixing valve until the furnace temperature of the heating section of the furnace wall drops to the set furnace temperature.

10. The control method for the oxygen-enriched combustion system of the heating furnace according to claim 7, characterized in that: When the furnace temperature of the top heating section of the heating furnace under step (2) is higher than the set furnace temperature, first reduce the opening of the high calorific value gas valve. When the opening of the high calorific value gas valve is zero, but the furnace temperature of the top heating section of the heating furnace is still higher than the set furnace temperature, then reduce the opening of the mixed gas valve and the low calorific value gas valve until the furnace temperature of the top heating section of the heating furnace drops to the set furnace temperature.

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