System for supplying combustion-supporting air to hot blast stove through anti-surge valve of air blower

Abstract

The invention provides a system for supplying combustion-supporting air to a hot-blast stove through an anti-surge valve of an air blower, and belongs to the field of ferrous metallurgy energy utilization. According to the system, an air supply pipeline is led out behind an anti-surge valve and in front of a blow-off valve and laid to an outlet of an air heat exchanger of a hot blast stove system, and the purpose is to secondarily utilize high-temperature oxygen-enriched air discharged in order to prevent surge of an air blower, so that the high-temperature oxygen-enriched air participates in combustion of coal gas in the hot blast stove. During daily blast furnace operation, the anti-surge valve can be regulated and controlled according to the air condition in the furnace, so that high-temperature oxygen-enriched air participates in gas combustion of the hot blast furnace. The technology effectively reduces the frequency of a combustion fan, reduces the energy consumption, improves the efficiency of the hot blast stove, reduces the emission of pollutants such as residual carbon monoxide and nitrogen oxides, optimizes the collaborative operation between the blast furnace and the hot blast stove system, improves the energy utilization rate and environmental protection benefits of the whole ferrous metallurgy production process, and improves the economic benefit. And an effective technical solution is provided for energy conservation and emission reduction in the iron and steel industry.

Description

Technical Field

[0001] The invention relates to a blast furnace smelting air supply technology, in particular to a system for a blower anti-surge valve to supply combustion-supporting air to a hot blast furnace, and belongs to the field of energy utilization in iron and steel metallurgy. Background Art

[0002] In the iron and steel metallurgical industry, the stable operation of the blast furnace is crucial to the entire production process. Take a certain unit's 550 cubic meter blast furnace as an example. It is equipped with an AV45 model blower and adopts a medium-pressure oxygen enrichment process before the machine. In the actual production process, in order to ensure that the required air volume can be stably provided, the static blade angle of the blower is usually maintained at around 45 degrees all year round. However, such operation makes the wind pressure slightly higher than the actual demand of the blast furnace system, resulting in a "pressure holding" phenomenon in the blast furnace.

[0003] When the pressure in the furnace is too high, in order to ensure the safety of the blast furnace equipment and the stability of the production process, the opening of the blower's anti-surge valve must be adjusted. Generally, the anti-surge valve will be opened to about 14 degrees for pressure relief operation. However, this process brings many problems. On the one hand, due to the opening of the anti-surge valve, a large amount of oxygen-rich air with a temperature of up to 160°C and a pressure of 300kpa is directly discharged into the atmosphere. The emission of this gas not only causes a huge waste of energy, but also from the perspective of power consumption, compared with the state of the anti-surge valve being fully closed, the average daily power consumption will increase by 2000kwh, which undoubtedly increases the production cost and energy burden of the enterprise.

[0004] On the other hand, in the hot blast furnace system, its furnace burning operation requires combustion-supporting air. The combustion-supporting air must first be heated by a heat exchanger, and then participate in the combustion process of the blast furnace gas in the combustion chamber to minimize heat loss and temperature loss. However, under the current process conditions, even with the participation of combustion-supporting air, there are still incompletely burned carbon monoxide and nitrogen oxides in the flue gas discharged from the hot blast furnace. These incompletely burned gases not only indicate that there is room for improvement in the current combustion efficiency, but also cause environmental pollution when discharged into the atmosphere, which does not meet the requirements of modern green and environmentally friendly production. In summary, the existing blast furnace blower and hot blast furnace system have many problems in energy waste, low efficiency and environmental pollution during operation. Summary of the invention

[0005] A brief overview of the present invention is provided below in order to provide a basic understanding of certain aspects of the present invention. It should be understood that this overview is not an exhaustive overview of the present invention. It is not intended to identify key or important parts of the present invention, nor is it intended to limit the scope of the present invention. Its purpose is merely to present certain concepts in a simplified form as a prelude to a more detailed description discussed later.

[0006] In view of this, in order to solve the practical problems existing in the prior art of energy waste, low efficiency and environmental pollution during the operation of the existing blast furnace blower and hot blast stove system, the present invention provides a blower anti-surge valve to supply combustion-supporting air to the hot blast stove.

[0007] The technical solution of the present invention is a system for supplying combustion-supporting air to a hot blast furnace through a blower anti-surge valve, comprising a main motor, a speed increaser, a blower, a gear box, a turbine, a blower air inlet duct, a blower air supply duct, an anti-surge valve, a relief valve, a relief chimney, an air supply duct, a hot blast furnace combustion-supporting blower, an air heat exchanger, a combustion-supporting air duct, and a hot blast furnace;

[0008] The main motor is connected to the blower through a speed increaser, the main motor serves as a power source, and the speed increaser provides the speed requirement for the blower;

[0009] The turbine is connected to the blower through a gear box;

[0010] The filter is connected to the blower through the blower air inlet duct;

[0011] The high-temperature oxygen-rich gas generated by the blower is transported to the hot blast furnace through the blower air supply pipeline to participate in the combustion of coal gas; the blower air supply pipeline is connected to a vent pipe, and an anti-surge valve and a vent valve are provided on the vent pipe. When the blower output wind pressure is greater than the requirement of the hot blast furnace, the anti-surge valve and the vent valve are opened to release the pressure, so that part of the high-temperature oxygen-rich gas passes through the anti-surge valve and the vent valve, and is discharged into the atmosphere after passing through the vent chimney;

[0012] The air supply pipeline is connected to the relief pipe, and its inlet end is arranged between the anti-surge valve and the relief valve. When the anti-surge valve is opened to release pressure and the relief valve is closed, the high-temperature oxygen-rich gas can be transmitted along the air supply pipeline;

[0013] The air heat exchanger is provided with a combustion-supporting air inlet and a combustion-supporting air outlet. The combustion-supporting air generated by the combustion-supporting air fan of the hot blast furnace enters the air heat exchanger through the combustion-supporting air inlet for heating. After the heating is completed, the combustion-supporting air enters the combustion-supporting air duct from the combustion-supporting air outlet and is transported to the hot blast furnace to participate in the combustion of coal gas.

[0014] The outlet end of the air supply pipe is connected to the combustion-supporting air pipe, and the high-temperature oxygen-rich gas generated by pressure relief is transported to the combustion-supporting air pipe through the air supply pipe, and is transported to the hot blast furnace together with the combustion-supporting air generated by the hot blast furnace combustion-supporting blower to participate in gas combustion.

[0015] Furthermore, an air supply pipeline control valve is provided on the air supply pipeline.

[0016] Furthermore, a filter is provided at the inlet end of the blower air inlet duct.

[0017] Furthermore, the vent pipe and the air supply pipe are pipes of equal diameter. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0019] Figure 1 This is a schematic diagram of a system in which a blower anti-surge valve supplies combustion-supporting air to a hot blast stove.

[0020] In the figure: 1-main motor, 2-speed increaser, 3-blower, 4-gear box, 5-turbine, 6-filter, 7-blower air inlet duct, 8-blower air supply duct, 9-anti-surge valve, 10-release valve, 11-release chimney, 12-air supply duct, 13-air supply duct control valve, 14-hot blast furnace combustion-supporting fan, 15-air heat exchanger, 16-combustion-supporting air duct, 17-hot blast furnace. DETAILED DESCRIPTION

[0021] In order to make the technical solutions and advantages of the embodiments of the present invention more clearly understood, the exemplary embodiments of the present invention are further described in detail below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than an exhaustive list of all the embodiments. It should be noted that the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict.

[0022] Example 1, reference Figure 1 To illustrate the present embodiment, a system for supplying combustion-supporting air to a hot blast furnace through a blower anti-surge valve includes a main motor 1, a speed increaser 2, a blower 3, a gear box 4, a turbine 5, a blower air inlet duct 7, a blower air supply duct 8, an anti-surge valve 9, a relief valve 10, a relief chimney 11, an air supply duct 12, a hot blast furnace combustion-supporting blower 14, an air heat exchanger 15, a combustion-supporting air duct 16, and a hot blast furnace 17;

[0023] The main motor 1 is connected to the blower 3 through the speed increaser 2. The main motor 1 serves as a power source, and the speed increaser 2 provides the speed requirement for the blower 3.

[0024] The turbine 5 is connected to the blower 3 via a gear box 4;

[0025] The filter 6 is connected to the blower 3 through the blower air inlet duct 7;

[0026] The high-temperature oxygen-rich gas generated by the blower 3 is transported to the hot blast furnace 17 through the blower air supply pipeline 8 to participate in the combustion of coal gas; the blower air supply pipeline 8 is connected to a vent pipe, and an anti-surge valve 9 and a vent valve 10 are provided on the vent pipe. When the output wind pressure of the blower 3 is greater than that required by the hot blast furnace 17, the anti-surge valve 9 and the vent valve 10 are opened to release the pressure, so that part of the high-temperature oxygen-rich gas passes through the anti-surge valve 9 and the vent valve 10 and is discharged into the atmosphere through the vent chimney 11;

[0027] The air supply pipeline 12 is connected to the release pipe, and its inlet end is arranged between the anti-surge valve 9 and the release valve 10. When the anti-surge valve 9 is opened to release pressure and the release valve 10 is closed, the high-temperature oxygen-rich gas can be transmitted along the air supply pipeline 12;

[0028] The air heat exchanger 15 is provided with a combustion-supporting air inlet and a combustion-supporting air outlet. The combustion-supporting air generated by the hot blast furnace combustion-supporting air fan 14 enters the air heat exchanger 15 through the combustion-supporting air inlet for heating. After heating, the combustion-supporting air enters the combustion-supporting air duct 16 from the combustion-supporting air outlet and is transported to the hot blast furnace 17 to participate in gas combustion.

[0029] The outlet end of the air supply pipe 12 is connected to the combustion-supporting air pipe 16, and the high-temperature oxygen-rich gas generated by pressure relief is transported to the combustion-supporting air pipe 16 through the air supply pipe 12, and is transported to the hot blast furnace 17 together with the combustion-supporting air generated by the hot blast furnace combustion-supporting blower 14 to participate in the gas combustion.

[0030] Furthermore, an air supply pipeline control valve 13 is provided on the air supply pipeline 12 .

[0031] Furthermore, a filter 6 is provided at the inlet end of the blower air inlet duct 7.

[0032] Furthermore, the vent pipe and the air supply pipe 12 are pipes of equal diameter.

[0033] The present invention can reduce the power consumption caused by opening the anti-surge valve to release pressure when the blower is working, and at the same time reduce the energy waste caused by exhausting high-temperature oxygen-rich air to the atmosphere;

[0034] The present invention can effectively improve the combustion efficiency of coal gas in the hot blast furnace, reduce the environmental pollution caused by the discharge of carbon monoxide and nitrogen oxide gases generated when the coal gas is not fully burned into the atmosphere, optimize the coordinated operation between the blast furnace and the hot blast furnace system, and improve the energy utilization rate and environmental protection benefits of the entire steel metallurgical production process.

[0035] Although the present invention has been described according to a limited number of embodiments, it will be apparent to those skilled in the art, with the benefit of the above description, that other embodiments may be envisioned within the scope of the invention thus described. In addition, it should be noted that the language used in this specification is selected primarily for readability and teaching purposes, rather than for explaining or defining the subject matter of the present invention. Therefore, many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the appended claims. The disclosure of the present invention is illustrative, not restrictive, with respect to the scope of the present invention, which is defined by the appended claims.

Claims

1. A system for supplying combustion-supporting air to a hot blast furnace with a blower anti-surge valve, characterized in that: It comprises a main motor (1), a speed increaser (2), a blower (3), a gear box (4), a turbine (5), a blower air inlet duct (7), a blower air supply duct (8), an anti-surge valve (9), a relief valve (10), a relief chimney (11), an air supply duct (12), a hot air furnace combustion-supporting blower (14), an air heat exchanger (15), a combustion-supporting air duct (16), and a hot air furnace (17); The main motor (1) is connected to the blower (3) via a speed increaser (2); the main motor (1) serves as a power source, and the speed increaser (2) provides a speed requirement for the blower (3); The turbine (5) is connected to the blower (3) via a gear box (4); The blower air inlet duct (7) is connected to the blower (3); The high-temperature oxygen-rich gas generated by the blower (3) is transported to the hot blast furnace (17) through the blower air supply pipeline (8) to participate in the combustion of coal gas; the blower air supply pipeline (8) is connected to a discharge pipe, and an anti-surge valve (9) and a discharge valve (10) are provided on the discharge pipe. When the output air pressure of the blower (3) is greater than the pressure required by the hot blast furnace (17), the anti-surge valve (9) and the discharge valve (10) are opened to release the pressure, so that part of the high-temperature oxygen-rich gas passes through the anti-surge valve (9) and the discharge valve (10) and is discharged into the atmosphere through a discharge chimney (11); The air supply pipeline (12) is connected to the release pipe, and its inlet end is arranged between the anti-surge valve (9) and the release valve (10). When the anti-surge valve (9) is opened to release pressure and the release valve (10) is closed, the high-temperature oxygen-rich gas can be transmitted along the air supply pipeline (12); The air heat exchanger (15) is provided with a combustion-supporting air inlet and a combustion-supporting air outlet. The combustion-supporting air generated by the hot blast furnace combustion-supporting air fan (14) enters the air heat exchanger (15) through the combustion-supporting air inlet for heating. After the heating is completed, the combustion-supporting air enters the combustion-supporting air duct (16) from the combustion-supporting air outlet and is transported to the hot blast furnace (17) to participate in the combustion of coal gas. The outlet end of the air supply pipe (12) is connected to the combustion-supporting air pipe (16), and the high-temperature oxygen-rich gas generated by pressure relief is transported to the combustion-supporting air pipe (16) through the air supply pipe (12), and is transported to the hot blast furnace (17) together with the combustion-supporting air generated by the hot blast furnace combustion-supporting blower (14) to participate in the combustion of coal gas.

2. According to claim 1, a blower anti-surge valve supplies combustion-supporting air to a hot blast stove, characterized in that: The air supply pipeline (12) is provided with an air supply pipeline control valve (13).

3. According to claim 1, a blower anti-surge valve supplies combustion-supporting air to a hot blast stove, characterized in that: A filter (6) is provided at the inlet end of the blower air inlet duct (7).

4. According to claim 1, a blower anti-surge valve supplies combustion-supporting air to a hot blast stove, characterized in that: The vent pipe and the air supply pipe (12) are pipes of equal diameter.

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