A hot blast furnace pressure equalizing system and gas supply method supporting multi-furnace pressure equalization

Abstract

The present invention relates to a hot blast furnace pressure equalizing system and gas supply method that supports multi-furnace pressure equalization, comprising an air inlet, a first intelligent pressure regulating pipeline, a second intelligent pressure regulating pipeline, a main discharge pipeline and an air outlet that are sequentially connected to form a pressure equalizing passage, separating the pressure regulation control of the high-pressure gas source from the control of the hot blast furnace itself, and connecting to the hot blast furnaces of multiple blast furnaces through an independently operated hot blast furnace pressure equalizing system, thereby achieving the effect of independent pressure equalization for multiple blast furnace hot blast furnaces without interfering with each other, and compared with the traditional single-seat blast furnace pressure equalizing technology, the project investment is low, the operation and maintenance are convenient, and the safety is high.

Description

Technical Field

[0001] The present invention relates to the technical field of blast furnace smelting equipment and hot blast stove control systems, and in particular to a hot blast stove pressure equalization system and a gas supply method that support multi-furnace pressure equalization. Background Art

[0002] Pig iron production is closely linked to hot blast furnaces. Their primary function is to provide sufficient high-temperature hot blast for the blast furnace, providing oxygen and heat for the smelting process. High blast temperatures are an effective measure to increase blast furnace output, reduce energy consumption, improve pig iron quality, and lower pig iron costs.

[0003] The working principle of the hot blast stove is to use the high-temperature flue gas generated during the hot blast stove combustion process to transfer heat energy to the checker bricks; the checker bricks absorb heat and heat up. When the temperature of the checker bricks reaches the required level, the hot blast stove stops burning and switches to air supply mode. The cold air provided by the blast furnace blower passes through the hot blast stove regenerator and is heated to high-temperature air and sent into the blast furnace to participate in the physical and chemical reactions of the smelting process. The high air temperature input can create favorable conditions for increasing the blast furnace output and reducing the coke ratio.

[0004] Based on the working principle of the hot blast stove, at this stage, in order to increase the air supply temperature of the hot blast stove, in addition to selecting a reasonable hot blast stove structure, high-efficiency burner, increasing the air gas preheating temperature, using oxygen-enriched furnace, improving the level of automation control and selecting a better operating system, in actual production processes, it is also common to shorten the air supply time to quickly increase the air supply temperature of the hot blast stove.

[0005] However, at present, the hot blast stoves in blast furnaces with existing technology generally have the phenomenon of long air supply time. The main reason is that most hot blast stoves use blast pressure charging to change the stove, which will cause large fluctuations in air volume and air pressure to the blast furnace during the stove change process. In order to stabilize the furnace condition, blast furnaces usually require hot blast stoves to extend the air supply time and reduce the number of stove changes. This unconventional operation often leads to reduced efficiency of the hot blast stove, a large temperature drop at the end, and serious heat loss of the heat storage body. In the long run, it poses a threat to the stability of the refractory structure and affects the service life of the hot blast stove to a certain extent. In order to reduce the number of hot blast stove changes and enable the hot blast stove to have the ability to supply air to the blast furnace for a long time, the thermal design capacity of newly built or modified hot blast stoves generally leaves a surplus of 10 to 30%. This is solved by improving matching capabilities and increasing project investment, but it significantly increases equipment investment and operating energy consumption, seriously affecting the cost of ironmaking.

[0006] In order to technically eliminate the fluctuations in air volume and pressure caused by traditional blast-pressurized furnace replacement, shorten the air supply time, and increase the temperature of the incoming air, various attempts have been made in existing technologies. For example, independent pressurization (independent pressure equalization) is used, that is, an additional independent pressurized air source is used to pressurize the hot blast furnace that needs to be replaced, thereby reducing the blast fluctuations caused by traditional blast-pressurized furnace replacement and creating conditions for shortening the air supply time. Among them, a relatively mature technical solution is to reduce the pressure of the independent high-pressure air source and quickly pressurize the hot blast furnace with a large flow rate. For example, the invention patent with publication number CN114774608A proposes a solution in which an independent gas source is stored in multiple gas tanks, and each gas tank outlet is pressure-regulated by an on-site pressure reducing device. However, due to the lack of parameterized control means, the effect of precise control of pressure regulation cannot be achieved, and it is difficult to meet process requirements in actual applications; the invention patent with publication number CN105803146A proposes to pressurize the independent gas source in a staged and large-flow manner, and based on the automated control of the hot blast furnace, the effect of precise control of pressure regulation can be achieved, but the project investment cost is high and the degree of intelligent operation is low.

[0007] It can be seen from this that the improvement of the existing technical solution for hot blast furnace pressure equalization is mainly aimed at the control of the pressurization process. Although it can solve the blast fluctuation problem of blast furnace caused by traditional blast pressure replacement to a certain extent by configuring an independent pressurized gas source, and create conditions for the hot blast furnace to shorten the air supply time, in actual use, it can only perform one-to-one pressure equalization operation on the hot blast furnace group of a single blast furnace, and is unable to achieve the ideal technical effect of simultaneously implementing pressure equalization on the hot blast furnace groups of multiple blast furnaces, resulting in a small scope of application of the existing technology's pressure equalization solution and limited improvement in utilization efficiency. Summary of the Invention

[0008] In order to address the deficiencies of the prior art, the present invention proposes a hot blast furnace pressure equalizing system and gas supply method that supports multi-furnace pressure equalization, separates the pressure regulation control of the high-pressure gas source from the hot blast furnace's own control, and connects the hot blast furnaces of multiple blast furnaces through an independently operated hot blast furnace pressure equalizing system, thereby achieving the effect of independent pressure equalization for multiple blast furnace hot blast furnaces without interfering with each other. Compared with the traditional single-seat blast furnace pressure equalization technology, the present invention has low project investment, convenient operation and maintenance, and high safety.

[0009] To achieve the above objectives, the technical solutions adopted by the present invention include:

[0010] A hot blast furnace pressure equalization system supporting multi-furnace pressure equalization, characterized by comprising an air inlet, a first intelligent pressure regulating pipeline, a second intelligent pressure regulating pipeline, a main discharge pipeline, and an air outlet connected in sequence to form a pressure equalization passage;

[0011] The air inlet is connected to the air storage device and the high-pressure air source of the air storage device is connected to the hot air furnace pressure equalization system;

[0012] The first intelligent pressure-regulating pipeline is connected to the air inlet and includes one or more first pressure-regulating sub-pipelines connected in parallel. The first pressure-regulating sub-pipelines include a first shut-off valve, a first filter, and a first pressure regulator arranged in sequence. The first pressure regulator is matched with a first pre-valve sensor and a first post-valve sensor. The first pre-valve sensor and the first post-valve sensor respectively monitor the gas pressure and gas flow before and after the first pressure regulator.

[0013] The second intelligent pressure regulating pipeline includes one or more groups of second pressure regulating sub-pipelines connected in parallel, the second pressure regulating sub-pipelines include a branch pipe, a second filter, and a second pressure regulator arranged in sequence, the second pressure regulator is matched with a second pre-valve sensor and a second post-valve sensor, the second pre-valve sensor and the second post-valve sensor respectively monitor the gas pressure and gas flow before and after the second pressure regulator, and the branch pipe is connected to the first intelligent pressure regulating pipeline;

[0014] The main relief pipeline is connected to the second intelligent pressure regulating pipeline, and includes a relief valve and a relief pipe arranged in sequence, and the relief pipe is connected to the outside atmosphere;

[0015] The gas outlet is connected to the second intelligent pressure regulating pipeline and sends the pressure-equalizing gas source into a hot blast furnace matching one blast furnace or into hot blast furnaces matching multiple different blast furnaces.

[0016] Furthermore, it also includes a control module and a power supply module;

[0017] The control module receives data collected by the first pre-valve sensor, the first post-valve sensor, the second pre-valve sensor, and the second post-valve sensor, and sends operating instructions to the first pressure regulator, the second pressure regulator, and the relief valve;

[0018] The power supply module is connected to the first intelligent pressure regulating pipeline, the second intelligent pressure regulating pipeline, the main discharge pipeline and the control module and provides driving power.

[0019] Furthermore, the first intelligent pressure regulating pipeline and the second intelligent pressure regulating pipeline are also provided with electric heating cables.

[0020] Furthermore, the first pressure regulator and the second pressure regulator include pressure reducing valves whose openings are adjusted according to operating instructions.

[0021] Furthermore, it also includes a voltage regulating cabinet, in which the first intelligent voltage regulating pipeline, the second intelligent voltage regulating pipeline, the control module and the power supply module are integrated.

[0022] The present invention also relates to a hot blast stove pressure equalization gas supply method supporting multi-furnace pressure equalization, which is characterized in that the hot blast stove pressure equalization system as described above is used to perform the hot blast stove pressure equalization gas supply.

[0023] Furthermore, the hot blast stove pressure-equalizing gas supply method includes:

[0024] S1, introduce high pressure gas source;

[0025] S2. Determine whether the pressure of the high-pressure gas source is lower than a preset threshold. If the pressure of the high-pressure gas source is lower than the preset threshold, stop the pressure-equalizing gas supply and send back an alarm signal.

[0026] S3. When it is determined that the pressure of the high-pressure gas source is not lower than the preset threshold, a charging signal is fed back, and a pressure equalization charging operation is performed according to the hot air furnace control instruction;

[0027] S4, determining whether the pressure difference in the hot blast furnace reaches a preset target value, and repeating step S3 when it is determined that the pressure difference in the hot blast furnace does not reach the preset target value;

[0028] S5. When it is determined that the pressure difference in the hot blast furnace reaches the preset target value, the pressure equalization and charging operation is stopped and the pressure equalization valve is closed.

[0029] Furthermore, the performing of the pressure equalization and charging operation includes the control module sending an operation instruction to the first intelligent pressure regulating pipeline and / or the second intelligent pressure regulating pipeline to adjust the pressure according to the cold air pressure parameter sent by the hot air stove system, and the pressure adjustment includes:

[0030] Adjust the first pressure regulator so that the output pressure of the first intelligent pressure regulating pipeline is between 0.6 and 1.0 MPa, and the pressure difference between the front and rear is between 0.2 and 0.8 MPa;

[0031] Adjust the second pressure regulator so that the output pressure of the second intelligent pressure regulating pipeline is between 0.3 and 0.6 MPa, and the pressure difference between the front and rear is between 0.05 and 0.3 MPa;

[0032] Adjust the second pressure regulator so that the outlet pressure is 0 to 600 kPa higher than the cold air working pressure of the hot air furnace.

[0033] Furthermore, the preset target value is any selected target pressure difference value within a range of 0 to 15 kPa.

[0034] The beneficial effects of the present invention are:

[0035] The hot blast furnace pressure equalizing system and gas supply method supporting multi-furnace pressure equalization described in the present invention are adopted to construct an independent pressure regulating system and integrate it into an independent pressure regulating cabinet, separate the pressure regulating control of the high-pressure gas source from the hot blast furnace's own control, and connect the hot blast furnaces of multiple blast furnaces through the independently operated hot blast furnace pressure equalizing system, and adapt to the flexibility requirements of the different operating conditions of multiple blast furnaces through data exchange and feedback control, so as to achieve the effect of independent pressure equalization for multiple blast furnace hot blast furnaces without interfering with each other. The hot blast furnace pressure equalizing system and gas supply method of the present invention can realize the modular combination and support of multiple sets of hot blast furnaces to meet the operating condition needs of large-volume pressure regulating and gas supply. Compared with the pressure equalizing technology of the traditional single-seat blast furnace hot blast furnace, the project investment is low, the operation and maintenance are convenient, and the safety is high. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 This is a schematic structural diagram of a preferred embodiment of a hot blast furnace pressure equalization system supporting multi-furnace pressure equalization according to the present invention.

[0037] Figure 2 The present invention is a flow chart of a method for hot blast furnace pressure equalization gas supply supporting multi-furnace pressure equalization.

[0038] Figure 3 This is a structural diagram of the first application embodiment of the present invention.

[0039] Figure 4 This is a structural diagram of the second application embodiment of the present invention.

[0040] Explanation of the accompanying figures: 10-gas storage device, 20-gas supply pipeline, 21-gas supply branch pipe, 30-hot blast furnace pressure equalization system, 300-air inlet, 301-air inlet main pipe, 302-first shut-off valve, 303-first filter, 304-first pressure regulator, 305-first valve front sensor, 306-first valve rear sensor, 307-branch pipe, 308-second filter, 309-second pressure regulator, 310-second valve front sensor, 311-second valve rear sensor, 312-outlet main pipe, 313-outlet Air inlet, 314- relief valve, 315- relief pipe, 316- control module, 317- power supply module, 318- pressure regulating cabinet, 40- first hot blast furnace, 50- second hot blast furnace, 60- third hot blast furnace, 41- first hot blast furnace group, 51- second hot blast furnace group, 61- third hot blast furnace group, 71- equalizing pressure valve, 72- differential pressure gauge, 73- cold air valve, 74- hot air valve, 75- hot air duct, 80- cold air duct, 90- blast furnace, 91- first blast furnace system, 92- second blast furnace system, 93- third blast furnace system. DETAILED DESCRIPTION

[0041] In order to more clearly understand the content of the present invention, it will be described in detail with reference to the accompanying drawings and embodiments.

[0042] like Figure 1 The figure shows a schematic diagram of a preferred embodiment of a hot blast furnace pressure equalization system supporting multi-furnace pressure equalization according to the present invention. The system includes an air inlet 300 for connecting to a gas storage device to receive a high-pressure gas source, an air outlet 313 for connecting to the hot blast furnace and delivering the pressure-equalizing gas source, a vent pipe 315 for connecting to the outside atmosphere, and a pressure-regulating cabinet 318. The pressure-regulating cabinet 318 integrates a first intelligent pressure-regulating pipeline, a second intelligent pressure-regulating pipeline, a control module 316, and a power supply module 317, making the hot blast furnace pressure-equalizing system 30 of the preferred embodiment a relatively independent, externally-mounted pressure-regulating system. In a preferred embodiment, the first intelligent pressure regulating pipeline includes a set of first pressure regulating sub-pipelines. The air inlet 300 is connected to the first shut-off valve 302 in the first pressure regulating sub-pipeline through the air inlet main pipeline 301, and is sequentially connected to the first filter 303 and the first pressure regulator 304. In particular, the first pressure regulator 304 is matched with a first valve pre-sensor 305 and a first valve post-sensor 306 to monitor the gas pressure and gas flow before and after the first pressure regulator 304, respectively. The second intelligent pressure regulating pipeline is connected to the back of the first intelligent pressure regulating pipeline, such as Figure 1 In the preferred embodiment shown, the second intelligent pressure-regulating pipeline comprises two sets of parallel second pressure-regulating sub-pipelines, each of which includes a branch pipe 307, a second filter 308, and a second pressure regulator 309. Specifically, each second pressure regulator 309 is equipped with a second pre-valve sensor 310 and a second post-valve sensor 311 for monitoring the gas pressure and flow rate before and after the second pressure regulator 309, respectively. The second pressure-regulating sub-pipelines are connected to the first intelligent pressure-regulating pipeline via branch pipes 307 to form a gas pathway. After being regulated by the second pressure regulator 309, the second pressure-regulating sub-pipelines converge into a main gas outlet pipeline 312 and connect to a gas outlet 313. The main gas outlet pipeline 312 is also connected to a main relief pipeline, including a relief valve 314 and a relief pipe 315. By controlling the opening and closing of the relief valve 314, the main gas outlet pipeline 312 can be selectively connected to the outside atmosphere for maintenance or automatic venting in the event of a pressure overload.

[0043] Preferably, the first pressure regulator 304 and the second pressure regulator 309 can be selected as pressure reducing valves whose openings are adjusted according to operating instructions as needed.

[0044] The control module 316 is connected to the specific functional components on the first intelligent pressure regulating pipeline, the second intelligent pressure regulating pipeline, and the main vent pipeline and exchanges data, including receiving the collected data from the first valve pre-sensor 305, the first valve post-sensor 306, the second valve pre-sensor 310, and the second valve post-sensor 311, and sending operation instructions to the first pressure regulator 304, the second pressure regulator 309, and the vent valve 314. The control module 316 is also connected to the hot blast stove and / or blast furnace related monitoring devices, instruction sending devices, etc. through an external data path to receive the operation monitoring data of the hot blast stove and / or blast furnace and related operation requests or automation control parameters. The power supply module 317 is used to provide the necessary driving power to the functional components within the hot blast stove pressure equalization system 30, so that the hot blast stove pressure equalization system 30 can achieve independent operation.

[0045] Preferably, the first intelligent pressure regulating pipeline and the second intelligent pressure regulating pipeline may also be provided with electric heating cables to prevent the pipeline from "frosting". The electric heating cables may preferably be connected to the control module 316 and the control module 316 may send corresponding instructions to operate.

[0046] The present invention also relates to a method for supplying hot blast furnace with equalized pressure using the above system, the process is as follows: Figure 2 Shown, including:

[0047] S1. Introducing a high-pressure gas source. For example, the high-pressure gas source of the gas storage bag is introduced into the pressure regulating cabinet 318 through the gas inlet 300.

[0048] S2. Determine whether the air pressure of the high-pressure air source is lower than a preset threshold. When it is determined that the air pressure of the high-pressure air source is lower than the preset threshold, stop the pressure-equalizing air supply and feedback an alarm signal.

[0049] Specifically, the first pre-valve sensor 305 detects the pressure of the high-pressure gas source. If the gas source pressure is lower than the lower limit of the first pre-valve sensor 305, the local control system transmits a signal to the hot blast furnace basic automation control system, and an alarm signal is generated to indicate that the hot blast furnace basic automation control system does not have the conditions for pressure equalization. If the gas source pressure is higher than the lower limit of the pre-valve sensor, the local control system transmits a signal to the hot blast furnace basic automation control system to indicate that pressure charging is possible.

[0050] S3. When it is determined that the pressure of the high-pressure gas source is not lower than the preset threshold, a charging signal is fed back, and a pressure equalization charging operation is performed according to the hot air furnace control instruction.

[0051] Specifically, the pressure equalization and charging operation includes the control module 316 sending an operation instruction to the first intelligent pressure regulating pipeline and / or the second intelligent pressure regulating pipeline to adjust the pressure according to the cold air pressure parameter sent by the hot blast furnace system, that is, controlling the first intelligent pressure regulating pipeline and the second intelligent pressure regulating pipeline to perform graded pressure adjustment on the high-pressure gas source. The pressure adjustment includes: adjusting the first pressure regulator 304 so that the output pressure of the first intelligent pressure regulating pipeline is between 0.6 and 1.0 MPa, and the front-to-back pressure difference is between 0.2 and 0.6 MPa; adjusting the second pressure regulator 309 so that the output pressure of the second intelligent pressure regulating pipeline is between 0.3 and 0.6 MPa, and the front-to-back pressure difference is between 0.05 and 0.3 MPa; and adjusting the second pressure regulator 309 so that the pressure at the outlet 313 is 0 to 600 kPa higher than the cold air working pressure of the hot blast furnace.

[0052] S4. The hot blast furnace basic automation monitors the pressure differential within the furnace to determine whether the pressure differential within the hot blast furnace has reached a preset target value. If the pressure differential within the hot blast furnace has not reached the preset target value, step S3 is repeated. Preferably, the preset target value can be any selected target pressure differential value within the range of 0 to 15 kPa, and can be adjusted as needed during operation.

[0053] S5. When it is determined that the pressure difference in the hot blast furnace reaches the preset target value, the pressure equalization and charging operation is stopped, and the hot blast furnace basic automation control furnace side pressure equalization valve is closed. At the same time, a pressure charging end instruction can be issued and subsequent air supply instructions can be executed as needed.

[0054] The following describes two application examples to illustrate the specific application of the hot blast furnace pressure equalization system 30 supporting multi-furnace pressure equalization in different blast furnace systems.

[0055] like Figure 3 The first embodiment of the present invention is shown, corresponding to an application scenario in which the hot blast stove pressure equalizing system 30 of the present invention is used to equalize the pressure of multiple hot blast stoves in a single blast furnace. The first embodiment includes a gas storage device 10, a gas supply pipeline 20, a hot blast stove pressure equalizing system 30, a gas supply branch pipe 21, a first hot blast stove 40, a second hot blast stove 50, a third hot blast stove 60, and a blast furnace 90. The first hot blast stove 40, the second hot blast stove 50 and the third hot blast stove 60 are respectively equipped with main and branch pipes of cold air duct 80 and hot air duct 75 to form a passage, and a cold air valve 73 and a hot air valve 74 are respectively provided for each hot blast stove; the cold air duct 80 is respectively connected with each hot blast stove, and controls the cold air source input into the first hot blast stove 40, the second hot blast stove 50 and the third hot blast stove 60 through the corresponding cold air valve 73; the hot air duct 75 is respectively connected with each hot blast stove, and controls the hot air source input into the blast furnace 90 from the first hot blast stove 40, the second hot blast stove 50 and the third hot blast stove 60 through the corresponding hot air valve 74.

[0056] During the actual pressure equalization operation, the cold air source input to the hot blast furnace is controlled to be provided by the blast furnace 90 blower, with a pressure of 0.3~0.6MPa. It is sent into one or two of the first hot blast furnace 40, the second hot blast furnace 50 and the third hot blast furnace 60 through the cold air duct 80 and the cold air valve 73, and is heated into high-temperature air by the heat storage body in the hot blast furnace; then it is sent into the blast furnace 90 through the hot air duct 75 and the hot air valve 74 to provide the required oxygen and heat energy for the smelting process.

[0057] The cold air duct 80 is connected to the first hot blast furnace 40, the second hot blast furnace 50 and the third hot blast furnace 60 through the cold air valve 73 and the corresponding cold air branch pipe. A pressure differential gauge 72 is provided before and after each cold air valve 73. The air supply branch pipe 21 is connected to the cold air branch pipe between the cold air valve 73 and each hot blast furnace. A pressure equalizing valve 71 is provided on each air supply branch pipe 21. The pressure equalizing valve 71 can control the air supply branch pipe 21 to pressurize each hot blast furnace, so that when the hot blast furnace switches from the combustion mode to the air supply mode, the pressure in the furnace can be increased to a level close to the cold air pressure. When the pressure in the hot blast furnace reaches the process requirement, the opening signal is transmitted to the cold air valve 73 through the pressure differential gauge 72, so that the cold air valve 73 can be opened, and cold air is supplied to the corresponding hot blast furnace and heated into high-temperature hot air, thereby providing the blast furnace 90 with the oxygen and heat energy required for smelting.

[0058] When the hot blast furnace switches from combustion mode to air supply mode, the pressure inside the hot blast furnace is typically 0-10 kPa, while the cold air source pressure provided by the blower is typically 0.3-0.6 MPa. The process requirement for the pressure differential gauge 72 to control the opening of the cold air valve 73 is typically a pressure difference ΔP of 0-15 kPa. The pressure of the gas source pressurized to the hot blast furnace by the gas supply branch pipe 21 is approximately 0-600 kPa higher than the cold air source pressure. This difference is provided by the hot blast furnace pressure equalization system 30.

[0059] Corresponding to the first application embodiment described above, the method for pressure equalization of a single blast furnace hot blast stove may include performing the following steps:

[0060] A1: The high-pressure gas source in the gas storage device 10 is connected to the hot blast furnace pressure equalizing system 30 through the gas supply pipeline 20.

[0061] A2: The hot blast furnace pressure equalization system 30 opens the shut-off valve of the first intelligent pressure regulating pipeline. The first pre-valve sensor 305 detects the gas source pressure provided by the gas storage device 10. If the gas source pressure is lower than 0.6 MPa, a signal is transmitted remotely from the local control system to the hot blast furnace control system, and an alarm is issued to indicate that the hot blast furnace basic automation control system is not ready for pressurization. If the gas source pressure is higher than 0.6 MPa, a signal is transmitted remotely from the local control system to the hot blast furnace control system, indicating that the conditions for pressurization are met.

[0062] A3: According to step A2, if the pressurization conditions are met, the hot blast stove control system issues a pressurization instruction to any one of the first hot blast stove 40, the second hot blast stove 50 and the third hot blast stove 60 as the target hot blast stove.

[0063] A4: The hot blast stove control system controls the target hot blast stove among the first hot blast stove 40 , the second hot blast stove 50 and the third hot blast stove 60 to open the pressure equalizing valve 71 .

[0064] A5: The control module 316 of the hot blast furnace pressure equalization system 30 controls the first and second intelligent pressure regulating pipelines to regulate the pressure of the gas source provided by the gas storage device 10 based on the obtained cold air pressure parameters of the hot blast furnace. For example, if the cold air pressure is 0.35 MPa and the high-pressure gas source is 1.1 MPa, the inlet pressure of the first intelligent pressure regulating pipeline is 1.1 MPa, the outlet pressure is controlled between 0.5 and 0.9 MPa, and the pressure differential between the front and rear ends is 0.2 and 0.6 MPa. The inlet pressure of the second intelligent pressure regulating pipeline is 0.5 to 0.9 MPa, the outlet pressure is controlled between 0.5 and 0.65 MPa, and the pressure differential between the front and rear ends is 0 to 0.25 MPa.

[0065] A6: The pressure differential meter 72 of the target hot blast furnace among the first hot blast furnace 40, the second hot blast furnace 50, and the third hot blast furnace 60 feeds back the pressure difference between the hot blast furnace and the cold air pressure to the hot blast furnace control system in real time. If the pressure difference is higher than 10kPa, continue to execute step A4 and maintain the open state of the equalizing pressure valve 71; the hot blast furnace equalizing pressure system 30 continues to supply gas to the hot blast furnace for pressurization according to the pressure control of step A5. If the pressure difference is 5-10kPa, the pressurized hot blast furnace pressure differential meter 72 sends a pressurization end signal to the hot blast furnace control system. If the pressure difference is less than 5kPa, the pressurized hot blast furnace pressure differential meter 72 sends an overpressure alarm signal to the control module 316 of the hot blast furnace equalizing pressure system 30 through the hot blast furnace control system. The control module 316 issues an emergency release command to the release valve 314 to ensure that the pressure inside the hot blast furnace is not higher than the cold air pressure.

[0066] A7: According to the pressure charging end signal issued in step A6, the hot blast stove control system closes the pressure equalizing valve 71 of the pressurized hot blast stove.

[0067] A8: Based on the closing signal of the equalizing valve 71 received in step A7, the hot blast stove control system issues an air supply instruction, and opens the cold air valve 73 and the hot air valve 74 of the pressurized hot blast stove in sequence, thereby realizing the process of supplying cold air to the pressurized hot blast stove, heating the cold air, and supplying the hot blast stove to the blast furnace 90.

[0068] like Figure 4The second application embodiment of the present invention is shown, which corresponds to the application scenario of using the hot blast stove pressure equalizing system 30 of the present invention to equalize the pressure of multiple hot blast stoves in three blast furnace systems. Among them, the second application embodiment includes a gas storage device 10, a gas supply pipeline 20, a hot blast stove pressure equalizing system 30, a gas supply branch pipe 21, a first blast furnace system 91, a second blast furnace system 92 and a third blast furnace system 93. The first blast furnace system 91, the second blast furnace system 92 and the third blast furnace system 93 are respectively configured with a first hot blast stove group 41, a second hot blast stove group 51 and a third hot blast stove group 61, and the first hot blast stove group 41, the second hot blast stove group 51 and the third hot blast stove group 61 can be configured with multiple hot blast stoves as needed, for example, three independently operated hot blast stoves are configured in the hot blast stove group ( Figure 4 The blast furnace devices in each blast furnace system are omitted, and a hot blast furnace symbol is used to represent the corresponding hot blast furnace group. Each hot blast furnace in the first hot blast furnace group 41, the second hot blast furnace group 51, and the third hot blast furnace group 61 is equipped with a cold air duct 80 and a hot air duct 75 with related main and branch pipes to form a passage, and a cold air valve 73 and a hot air valve 74 are respectively provided for each hot blast furnace; the cold air duct 80 is respectively connected to each hot blast furnace and controls the cold air source input to each hot blast furnace in the first hot blast furnace group 41, the second hot blast furnace group 51, and the third hot blast furnace group 61 through the corresponding cold air valve 73; the hot air duct 75 is respectively connected to each hot blast furnace group and controls the hot air source from the first hot blast furnace group 41, the second hot blast furnace group 51, and the third hot blast furnace group 61 to the corresponding blast furnace through the corresponding hot air valve 74.

[0069] During the actual pressure equalization operation, the cold air source input to the hot blast furnace is controlled by the blast furnace blower with a pressure of 0.3~0.6MPa. It is sent into one or two hot blast furnaces in each hot blast furnace group through the cold air pipe and cold air valve 73, and heated into high-temperature air by the heat storage body in the hot blast furnace; then it is sent into the corresponding blast furnace through the hot air pipe 75 and the hot air valve 74 to provide the required oxygen and heat energy for the smelting process.

[0070] The cold air duct 80 is connected to each hot blast furnace in the first hot blast furnace group 41, the second hot blast furnace group 51 and the third hot blast furnace group 61 through the cold air valve 73 and the corresponding cold air branch pipe. A pressure differential gauge 72 is provided before and after each cold air valve 73. The air supply branch pipe 21 is connected to the cold air branch pipe between the cold air valve 73 and each hot blast furnace. Each air supply branch pipe 21 is provided with a pressure equalizing valve 71. The pressure equalizing valve 71 can control the air supply branch pipe 21 to pressurize each hot blast furnace, so that when the hot blast furnace switches from combustion mode to air supply mode, the pressure inside the furnace can be increased to a level close to the cold air pressure. When the pressure inside the hot blast furnace reaches the process requirement, the pressure differential gauge 72 transmits an opening signal to the cold air valve 73, so that the cold air valve 73 can be opened, and cold air is supplied to the corresponding hot blast furnace and heated into high-temperature hot air, thereby providing the blast furnace with the oxygen and heat energy required for smelting.

[0071] When the hot blast furnace switches from combustion mode to air supply mode, the pressure inside the hot blast furnace is typically 0-10 kPa, while the cold air source pressure provided by the blower is typically 0.3-0.6 MPa. The process requirement for the pressure differential gauge 72 to control the opening of the cold air valve 73 is typically a pressure difference ΔP of 0-15 kPa. The pressure of the gas source pressurized to the hot blast furnace by the gas supply branch pipe 21 is approximately 0-600 kPa higher than the cold air source pressure. This difference is provided by the hot blast furnace pressure equalization system 30.

[0072] Corresponding to the above-mentioned second application embodiment, the method for equalizing the pressure of the hot blast furnaces of the three blast furnace systems may include two different situations. In one of the situations, when the hot blast furnaces of each of the three blast furnaces in the blast furnace system respectively perform the conversion operation from the combustion mode to the air supply mode at fixed intervals, the method is implemented according to the pressurized gas supply method of a single blast furnace hot blast furnace, and the control steps are similar to those of the first application embodiment. In another situation, when the conversion operation of the hot blast furnace of one of the three blast furnaces does not overlap with the other two blast furnaces, the method is implemented according to the pressurized gas supply method of a single blast furnace hot blast furnace, and the control steps are as in the first application embodiment; when the time of the conversion operation from the combustion mode to the air supply mode of the other two blast furnaces overlaps, the gas supply method may include executing the following steps:

[0073] B1: The high-pressure gas source in the gas storage device 10 is connected to the hot blast furnace pressure equalizing system 30 through the gas supply pipeline 20.

[0074] B2: The hot blast furnace pressure equalization system 30 opens the first shut-off valve 302 of the first intelligent pressure regulating pipeline. The first pre-valve sensor 305 detects the gas source pressure provided by the gas storage device 10. If the gas source pressure is lower than 1.0 MPa, a signal is transmitted remotely from the local control system to the hot blast furnace control system, and an alarm is issued to indicate that the hot blast furnace basic automation control system is not ready for pressurization. If the gas source pressure is higher than 1.0 MPa, a signal is transmitted remotely from the local control system to the hot blast furnace control system, indicating that the conditions for pressurization are met.

[0075] B3: Based on the judgment in step B2, and provided that the pressurizing conditions are met, the hot blast stove control systems of the two blast furnaces respectively issue a pressurizing instruction to any target hot blast stove in the corresponding hot blast stove group.

[0076] B4: The hot blast stove control systems of the two blast furnaces independently control the corresponding target hot blast stoves to open the equalizing valve 71.

[0077] B5: The control module 316 of the hot blast furnace pressure equalization system 30 controls the first and second intelligent pressure regulating pipelines to regulate the pressure of the gas source provided by the gas storage device 10 based on the obtained hot blast furnace cold air pressure parameters. For example, if the cold air pressure of the first blast furnace system 91 is 0.35 MPa, the cold air pressure of the second blast furnace system 92 is 0.42 MPa, and the high-pressure gas source is 1.2 MPa, the inlet pressure of the first intelligent pressure regulating pipeline is 1.2 MPa, the outlet pressure is controlled to be 0.7-1.0 MPa, and the pressure difference between the front and rear is 0.2-0.5 MPa; the inlet pressure of the second intelligent pressure regulating pipeline is 0.7-1.0 MPa, the outlet pressure is controlled to be 0.6-0.8 MPa, and the pressure difference between the front and rear is 0.1-0.2 MPa.

[0078] B6: The pressure difference meter 72 of the target hot blast furnace of each blast furnace feeds back the pressure difference between the hot blast furnace and the cold air pressure to the hot blast furnace control system of each blast furnace in real time. If the pressure difference of the target hot blast furnace in each blast furnace is higher than 10kPa, keep step B4 and maintain the open state of the equalizing pressure valve 71; the equalizing pressure system continues to supply gas to the hot blast furnace for pressurization according to the pressure regulation of step B5. If the pressure difference of the target hot blast furnace in each blast furnace is 5-10kPa, the target hot blast furnace pressure difference meter 72 for pressurization of each blast furnace sends a pressurization end signal to the hot blast furnace control system of each blast furnace. If the pressure difference of the target hot blast furnace in each blast furnace is less than 5kPa, the target hot blast furnace pressure difference meter 72 for pressurization of each blast furnace sends an overpressure alarm signal to the control module 316 of the hot blast furnace equalizing pressure system 30 through the hot blast furnace control system, and the control module 316 issues an emergency release instruction to the release valve 314 to ensure that the pressure in the hot blast furnace is not higher than the cold air pressure.

[0079] B7: According to the pressure charging end signal issued in step B6, the hot blast stove control system of each blast furnace closes the pressure equalization of the pressurized hot blast stove.

[0080] B8: Based on the closing signal of the equalizing valve 71 received in step B7, the hot blast furnace control system issues an air supply instruction, and opens the cold air valve 73 and the hot air valve 74 of the pressurized hot blast furnace in sequence, thereby realizing the process of supplying air to the pressurized hot blast furnace, heating the cold air, and supplying hot air to the blast furnace.

[0081] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention are intended to be covered by the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A hot blast furnace pressure equalization method supporting pressure equalization of multiple blast furnaces, characterized in that: The method is applied to a hot blast furnace pressure equalization system, comprising an air inlet, a first intelligent pressure regulating pipeline, a second intelligent pressure regulating pipeline, a main discharge pipeline, and an air outlet connected in sequence to form a pressure equalization passage; The first intelligent pressure-regulating pipeline is connected to the air inlet and includes one or more first pressure-regulating sub-pipelines connected in parallel. The first pressure-regulating sub-pipelines include a first shut-off valve, a first filter, and a first pressure regulator arranged in sequence. The first pressure regulator is matched with a first pre-valve sensor and a first post-valve sensor. The first pre-valve sensor and the first post-valve sensor respectively monitor the gas pressure and gas flow before and after the first pressure regulator. The second intelligent pressure regulating pipeline includes one or more groups of second pressure regulating sub-pipelines connected in parallel, the second pressure regulating sub-pipelines include a branch pipe, a second filter, and a second pressure regulator arranged in sequence, the second pressure regulator is matched with a second pre-valve sensor and a second post-valve sensor, the second pre-valve sensor and the second post-valve sensor respectively monitor the gas pressure and gas flow before and after the second pressure regulator, and the branch pipe is connected to the first intelligent pressure regulating pipeline; The main relief pipeline is connected to the second intelligent pressure regulating pipeline, and includes a relief valve and a relief pipe arranged in sequence, and the relief pipe is connected to the outside atmosphere; The gas outlet is connected to the second intelligent pressure regulating pipeline and sends the pressure-equalizing gas source to a hot blast furnace matching one blast furnace or to hot blast furnaces matching multiple different blast furnaces; It also includes a control module and a power supply module; The control module receives data collected by the first pre-valve sensor, the first post-valve sensor, the second pre-valve sensor, and the second post-valve sensor, and sends operating instructions to the first pressure regulator, the second pressure regulator, and the relief valve; The power supply module is connected to the first intelligent pressure regulating pipeline, the second intelligent pressure regulating pipeline, the main discharge pipeline and the control module and provides driving power; The air inlet is connected to the air storage device and the high-pressure air source of the air storage device is connected to the hot air furnace pressure equalization system; The hot blast furnace pressure equalizing system opens the shut-off valve of the first intelligent pressure regulating pipeline, and the first valve front sensor detects the gas source pressure provided by the gas storage device. If the gas source pressure is lower than 0.6 MPa, a signal is transmitted remotely to the hot blast furnace control system through the local control system, and an alarm signal is sent to the hot blast furnace basic automation control system to indicate that the conditions for pressurization are not met. If the gas source pressure is higher than 0.6 MPa, a signal is transmitted remotely to the hot blast furnace control system through the local control system to indicate that the conditions for pressurization are met. Under the premise of meeting the pressure charging conditions, the hot blast stove control system issues a pressure charging instruction to any hot blast stove as the target hot blast stove; The hot blast stove control system controls the target hot blast stove to open the pressure equalizing valve; The hot blast furnace pressure equalizing system controls the first intelligent pressure regulating pipeline and the second intelligent pressure regulating pipeline to adjust the pressure of the gas source provided by the gas storage device according to the obtained cold air pressure parameters of the hot blast furnace; The pressure differential gauge of the target hot blast stove feeds back the pressure difference between the hot blast stove and the cold air pressure to the hot blast stove control system in real time; if the pressure difference is higher than 10kPa, the equalizing pressure valve is maintained in the open state; the hot blast stove equalizing pressure system regulates the pressure according to the obtained cold air pressure parameters of the hot blast stove, and continues to supply air to the hot blast stove for pressurization; if the pressure difference is 5~10kPa, the pressurized hot blast stove differential pressure gauge sends a pressurization end signal to the hot blast stove control system; if the pressure difference is less than 5kPa, the pressurized hot blast stove differential pressure gauge sends an overpressure alarm signal to the control module of the hot blast stove equalizing pressure system via the hot blast stove control system, and the control module issues an emergency release instruction to the release valve to ensure that the pressure in the hot blast stove is not higher than the cold air pressure; According to the pressure-charging end signal, the hot blast furnace control system closes the pressure-equalizing valve of the pressurized hot blast furnace; According to the closing signal of the pressure equalizing valve, the hot air stove control system issues an air supply command to open the cold air valve and hot air valve of the pressurized hot air stove in sequence.

2. The hot blast stove pressure equalization method according to claim 1, characterized in that: The first intelligent pressure regulating pipeline and the second intelligent pressure regulating pipeline are further provided with electric heating cables.

3. The hot blast stove pressure equalization method according to claim 1, characterized in that: The first pressure regulator and the second pressure regulator include pressure reducing valves whose openings are adjusted according to operating instructions.

4. The hot blast stove pressure equalization method according to claim 1, characterized in that: It also includes a voltage regulating cabinet, in which the first intelligent voltage regulating pipeline, the second intelligent voltage regulating pipeline, the control module and the power supply module are integrated.

5. The hot blast stove pressure equalization method according to claim 1, characterized in that: The pressure regulation includes: Adjust the first pressure regulator so that the output pressure of the first intelligent pressure regulating pipeline is between 0.6 and 1.0 MPa, and the front and rear pressure difference is between 0.2 and 0.6 MPa; Adjust the second pressure regulator so that the output pressure of the second intelligent pressure regulating pipeline is between 0.3 and 0.8 MPa, and the pressure difference between the front and rear is between 0.05 and 0.3 MPa; Adjust the second pressure regulator so that the outlet pressure is 0 to 600 kPa higher than the cold air working pressure of the hot air furnace.

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