Voltage equalizing device and method thereof

Abstract

The invention discloses a pressure equalizing device and method, the pressure equalizing device comprises a pressure equalizing main body part and a hot blast stove connecting pipeline, the pressure equalizing main body part comprises a main body pipeline, a main body pipeline switch regulation and control unit, a pressurization unit and a gas storage unit; the main pipeline switch regulation and control unit, the pressurization unit and the gas storage unit are all arranged on the main pipeline, and the input end of the main pipeline communicates with the smoke output end of the hot blast stove; the hot blast stove connecting pipeline comprises a pressure equalizing header pipe and a plurality of pressure equalizing valves, the pressure equalizing header pipe is provided with pressure equalizing output branch pipes and pressure equalizing input branch pipes, the pressure equalizing output branch pipes are communicated with the corresponding hot blast stoves, the pressure equalizing valves are arranged on the corresponding pressure equalizing output branch pipes, and the pressure equalizing input branch pipes are communicated with the gas storage units of the corresponding pressure equalizing main body parts; the pressure equalizing device is provided with at least three pressure equalizing stages enabling the pressure in the hot blast stove to rise in a stepped mode. The method has the advantages that the blast furnace is free of any fluctuation during hot blast stove changing operation, furnace changing is rapid, and waste heat of the hot blast stove can be recycled.

Description

Technical Field

[0001] The present invention belongs to the field of pressure equalization technology, and in particular relates to a pressure equalization device and a method thereof. Background Art

[0002] At present, most blast furnaces at home and abroad are equipped with three hot blast stoves, most of which adopt the two-burning and one-sending operation mode to achieve the purpose of heating the cold air through the hot blast stove and then sending it to the blast furnace uninterruptedly.

[0003] The hot blast furnace mainly has a furnace burning state and an air supply state during the production process; when the hot blast furnace is in the furnace burning state, the cold air valve is closed, and the air in the furnace and the flue gas from the combustion of coal gas are discharged from the hot blast furnace through the chimney through the flue valve. At this time, the hot blast furnace is under a slightly positive pressure. When the hot blast furnace is in the air supply state, the cold air valve is opened, and the cold air enters the hot blast furnace through the cold air valve for heating. After becoming hot air, it is sent to the blast furnace through the hot air duct. At this time, the pressure in the furnace is the pressure of the cold air duct, which is generally around 0.45MPa. The opening and closing of the cold air valve requires a pressure difference of no more than 0.01MPa on both sides. Therefore, when switching from the furnace burning state to the air supply state, the hot blast furnace needs to be pressure-equalized to ensure that the cold air valve can be opened. The commonly used method is to connect a small bypass duct next to the cold air valve and install a pressure-equalizing valve to pressure-equalize the hot blast furnace through the cold air in the cold air duct, but there are the following two defects:

[0004] 1) During the heat exchange process, the cold air in the furnace is not immediately heated and sent to the blast furnace, which results in a reduction in the hot air sent to the blast furnace during the period of equalization; or, while ensuring that the air volume entering the furnace remains unchanged, the working mode of the blower is adjusted to increase the air volume. Both of these methods affect the stability of blast furnace smelting;

[0005] 2) Since the pressure equalization pipeline is small and the pressure difference between the cold air pipeline and the hot blast furnace is not large enough in the later stage of pressure equalization, the pressure equalization time is generally long. During the pressure equalization stage, the hot blast furnace cannot supply air to the blast furnace. The furnace change time seriously affects the utilization efficiency of the hot blast furnace.

[0006] At the same time, the average temperature of the flue gas produced by the hot blast furnace is about 300℃. Although most steel mills have heat exchangers to recover this heat, the flue gas after heat exchange is still 140-150℃. Only a small part of this flue gas is used for coal injection, and most of the rest is discharged through the chimney, resulting in a waste of resources.

[0007] The information disclosed in this background technology section is only intended to enhance the understanding of the overall background of the invention and should not be regarded as an acknowledgment or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art. Summary of the invention

[0008] In order to solve the above-mentioned shortcomings of the hot blast furnace pressure equalization process in the prior art, a pressure equalization device and method are provided.

[0009] A first aspect of the present invention provides a pressure equalizing device, comprising:

[0010] The pressure-equalizing main body part includes a main pipeline, a main pipeline switch control unit, a pressurizing unit and a gas storage unit; the main pipeline switch control unit, the pressurizing unit and the gas storage unit are provided in a certain number and are all provided on the main pipeline, wherein the input end of the main pipeline is connected to the smoke output end of the hot blast stove;

[0011] The hot blast furnace connecting pipeline includes a pressure equalizing main pipe and a plurality of pressure equalizing valves, the pressure equalizing main pipe has a pressure equalizing output branch pipe and a pressure equalizing input branch pipe, and the number of the pressure equalizing output branch pipe and the pressure equalizing input branch pipe is a plurality, wherein the pressure equalizing output branch pipe is connected with the corresponding hot blast furnace, the pressure equalizing valve is arranged on the corresponding pressure equalizing output branch pipe, the pressure equalizing input branch pipe is connected with the corresponding gas storage unit of the pressure equalizing main part, and the pressure equalizing input branch pipe is provided with a branch pipe switch control unit;

[0012] The pressure equalizing device has at least three pressure equalizing stages for increasing the pressure in the hot blast furnace in a step-by-step manner; the pressure equalizing structures for implementing each pressure equalizing stage in the pressure equalizing device include a corresponding partial pipe section of the main pipeline, a main pipeline switch control unit, a pressurizing unit and an air storage unit, the pressurizing unit is connected in series with the air storage unit, and the air storage unit of each of the pressure equalizing structures is connected to the corresponding pressure equalizing input branch pipe.

[0013] In some embodiments, during the last pressure equalization stage of the pressure equalization device, when the pressure inside the hot blast furnace reaches the target value, the pressure difference on both sides of the cold air valve is less than the valve opening threshold, the cold air valve is opened, and the branch pipe switch control unit is closed, wherein the cold air valve is arranged on the pipe that transports cold air to the hot blast furnace.

[0014] In some embodiments, the main pipeline includes at least three main pipeline segments, and the number of the main pipeline segments is equal to the number of pressure equalizing stages of the pressure equalizing device.

[0015] In some embodiments, according to the order in which the flue gas flows through the pipeline nodes in each of the main pipeline segments, the main pipeline switch control unit, the pressurizing unit, and the gas storage unit are sequentially provided at different pipeline nodes on each of the main pipeline segments.

[0016] In some embodiments, the main pipeline switch control unit includes a cut-off valve.

[0017] In some embodiments, the branch pipe switch control unit includes a cut-off valve.

[0018] In some embodiments, the number of the hot air furnaces is three.

[0019] In some embodiments, the pressure equalizing device has three pressure equalizing stages for increasing the pressure in the hot blast stove in a step-by-step manner, and the pressure of the gas storage unit in the pressure equalizing structure implementing each pressure equalizing stage in the pressure equalizing device increases sequentially.

[0020] A second aspect of the present invention provides a pressure equalization method, which is implemented based on the above-mentioned pressure equalization device and includes the following steps:

[0021] First, the flue gas in the hot blast furnace is passed into the pressure-equalizing main body part from the input end of the main pipe, and the pressure-equalizing main body part includes the main pipe, the main pipe switch control unit, the pressurizing unit and the gas storage unit; the main pipe switch control unit, the pressurizing unit and the gas storage unit are provided in a certain number and are all provided on the main pipe, wherein the input end of the main pipe is connected with the flue gas output end of the hot blast furnace;

[0022] Then, each pressure equalizing structure in the pressure equalizing device is used to sequentially implement the corresponding pressure equalizing stage, wherein each pressure equalizing structure includes a corresponding partial pipe section of the main pipeline, a main pipeline switch control unit, a pressurizing unit and a gas storage unit, the pressurizing unit is connected in series with the gas storage unit, and the gas storage unit of each pressure equalizing structure is connected with the corresponding pressure equalizing input branch pipe, so that the pressure-equalizing flue gas output by the gas storage unit of the pressure equalizing structure in each pressure equalizing stage enters the corresponding pressure equalizing input branch pipe;

[0023] The pressure-equalizing flue gas in the pressure-equalizing input branch pipe is passed through the hot blast furnace connecting pipeline and output from the pressure-equalizing input branch pipe to the corresponding hot blast furnace, wherein the hot blast furnace connecting pipeline includes a pressure-equalizing main pipe and a plurality of pressure-equalizing valves, the pressure-equalizing main pipe has the pressure-equalizing output branch pipe and the pressure-equalizing input branch pipe, and the number of the pressure-equalizing output branch pipes and the pressure-equalizing input branch pipes is a plurality, wherein the pressure-equalizing output branch pipe is connected with the corresponding hot blast furnace, the pressure-equalizing valve is arranged on the corresponding pressure-equalizing output branch pipe, the pressure-equalizing input branch pipe is connected with the corresponding gas storage unit of the pressure-equalizing main part, and the pressure-equalizing input branch pipe is provided with a branch switch control unit; the pressure in the hot blast furnace is increased stepwise to the target value through at least three pressure-equalizing stages.

[0024] Compared with the prior art, the technical effects achieved by the present invention are as follows:

[0025] (1) The pressure equalization device of the present invention realizes a step-by-step increase in the pressure in the hot blast furnace by setting at least three pressure equalization stages and using an independent pressure equalization structure (including a partial pipe section of the main pipeline, a main pipeline switch control unit, a pressurizing unit and a gas storage unit) in each pressure equalization stage. This design can evenly adjust the pressure inside and outside the hot blast furnace, and the furnace change operation does not disturb the air volume entering the furnace, which can effectively avoid the interference of sudden pressure changes on the operation in the furnace, thereby ensuring that the furnace change process is smooth, and will not cause fluctuations in the operation of the hot blast furnace, and thus will not affect the blast furnace smelting.

[0026] (2) The pressurizing unit and the gas storage unit of the pressure equalizing device of the present invention are designed in series, which realizes the internal circulation pressurizing function of the blast furnace flue gas, rather than relying on an external air compressor to provide the gas source. This design not only reduces the initial investment cost of the equipment, but also reduces the land demand for additional air compressors and the energy consumption and maintenance costs in the later operation, thereby reducing the overall production cost and control cost.

[0027] (3) The pressure equalization device of the present invention connects the flue gas output end of the hot blast furnace with the pressure equalization main body, so that the waste heat flue gas generated by the blast furnace can be fully recovered and used in the pressure equalization process. This resource utilization method effectively reduces the external energy consumption in the blast furnace ironmaking process, improves energy utilization efficiency, and has significant energy-saving and environmental protection effects.

[0028] (4) Since the pressure equalizing pipe is relatively small, when the pressure difference between the hot blast furnace and the pressure equalizing pipe is large, the noise during the pressure equalizing process will be very loud. When the pressure difference is not large enough, the pressure equalizing time will become very long. In order to solve this problem, the present invention adopts a step-by-step pressurization method by setting up multiple compressors and gas storage tanks in series to pressurize the flue gas. The gas storage unit in each pressure equalizing stage can provide flue gas of different pressures. The flue gas is transported to the hot blast furnace through the pressure equalizing pipe, so that the pressure difference between the hot blast furnace and the pressure equalizing pipe is always roughly controlled within the target value. Under the premise of achieving rapid pressure equalization, the noise pollution is reduced as much as possible, the pressure equalization efficiency is improved, the speed of the pressure equalization process is accelerated, and the operating efficiency of the hot blast furnace pressure equalization system is further optimized. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 Schematic diagram of the structure of a pressure equalizing device provided in one embodiment of the present invention. DETAILED DESCRIPTION

[0030] The technical solution of the present invention is described below by specific embodiments in conjunction with the accompanying drawings. It should be understood that one or more steps mentioned in the present invention do not exclude the existence of other methods and steps before and after the combination step, or other methods and steps can be inserted between these explicitly mentioned steps. It should also be understood that these examples are only used to illustrate the present invention and are not used to limit the scope of the present invention. Unless otherwise specified, the numbering of each method step is only for the purpose of identifying each method step, and is not intended to limit the order of arrangement of each method or to define the scope of implementation of the present invention. Changes or adjustments in their relative relationships can also be regarded as the scope of implementation of the present invention without substantial changes in the technical content.

[0031] The sources of the raw materials and instruments used in the examples are not particularly limited and can be purchased from the market or prepared according to conventional methods known to those skilled in the art.

[0032] like Figure 1As shown, a pressure equalizing device is provided, which ensures that the pressure of the pressure equalizing main pipe is always higher than that of the hot blast stove by about 0.2MPa during the pressure equalizing process through a series of step-by-step pressurization methods, thereby reducing the pressure equalization time and improving the utilization efficiency of the hot blast stove. The pressure equalizing device has the advantages of ensuring that the blast furnace does not fluctuate during the hot blast stove replacement operation, quickly replacing the stove, and recovering the waste heat of the hot blast stove.

[0033] The pressure equalizing device comprises: a pressure equalizing main body part and a hot air furnace connecting pipeline.

[0034] The pressure equalizing main body part includes a main pipeline, a main pipeline switch control unit, a pressurizing unit and a gas storage unit; the main pipeline switch control unit, the pressurizing unit and the gas storage unit are of several numbers and are all arranged on the main pipeline, wherein the input end of the main pipeline is connected with the flue gas output end of the hot blast furnace; in some embodiments, the number of hot blast furnaces is three (hot blast furnace No. 1, hot blast furnace No. 2 and hot blast furnace No. 3), each hot blast furnace has a hot blast outlet, the hot blast is connected to the hot blast main pipe through the hot blast branch pipe and the hot blast valve, and the hot blast main pipe passes the hot blast into the blast furnace.

[0035] Each hot air furnace also has a cold air inlet.

[0036] In some embodiments, the main pipeline switch control unit adopts a cut-off valve; in some embodiments, the pressurizing unit adopts a pressurizing machine; in some embodiments, the gas storage unit adopts a gas storage tank;

[0037] In some embodiments, the main pipeline includes at least three main pipeline segments connected in series in a linear shape, and the main pipeline segments and the pressure equalizing device have the same number of pressure equalizing stages. In some embodiments, the main pipeline includes three main pipeline segments, namely, a first main pipeline segment 1, a second main pipeline segment 2, and a third main pipeline segment 3, and the main pipeline segments and the pressure equalizing device have three pressure equalizing stages.

[0038] In some embodiments, according to the order in which the flue gas flows through the pipeline nodes in each main pipeline segment, a main pipeline switch control unit (for example, a regulating valve 4 and a cut-off valve), a pressurizing unit, and a gas storage unit are installed in sequence at different pipeline nodes on each main pipeline segment.

[0039] In some embodiments, the first main pipeline section 1 is sequentially provided with a regulating valve 4, a first cut-off valve 5, a first compressor 23, and a first gas storage tank 22, the second main pipeline section 2 is sequentially provided with a third cut-off valve 6, a second compressor 7, and a second gas storage tank 8, and the third main pipeline section 3 is sequentially provided with a fifth cut-off valve 9, a third compressor 10, and a third gas storage tank 11.

[0040] The hot blast furnace connecting pipeline includes a pressure equalizing main pipe and several pressure equalizing valves. The pressure equalizing main pipe has a pressure equalizing output branch and a pressure equalizing input branch. The pressure equalizing output branch is connected to the pressure equalizing input branch through a pressure equalizing intermediate pipe 18. The number of pressure equalizing output branches and pressure equalizing input branches is several (for example, the number of pressure equalizing output branches and pressure equalizing input branches is three, namely, the first pressure equalizing output branch 12, the second pressure equalizing output branch 13, the third pressure equalizing output branch 14, the first pressure equalizing input branch 15, the second pressure equalizing input branch 16, and the third pressure equalizing input branch 17), wherein the pressure equalizing output branch is connected to the corresponding hot blast furnace (for example, the output end of the first pressure equalizing output branch 12 is connected to the pressure equalizing inlet of hot blast furnace No. 1, the output end of the second pressure equalizing output branch 13 is connected to the pressure equalizing inlet of hot blast furnace No. 2, and the output end of the third pressure equalizing output branch 17 is connected to the pressure equalizing inlet of hot blast furnace No. 2). The output end of the pressure-equalizing output branch pipe 14 is connected to the pressure-equalizing inlet of hot blast furnace No. 3), the pressure-equalizing valve is arranged on the corresponding pressure-equalizing output branch pipe (for example, the first pressure-equalizing valve 24 is installed on the corresponding first pressure-equalizing output branch pipe 12, the second pressure-equalizing valve 25 is installed on the corresponding second pressure-equalizing output branch pipe 13, and the third pressure-equalizing valve 26 is installed on the corresponding third pressure-equalizing output branch pipe 14), the pressure-equalizing input branch pipe is connected to the gas storage unit of the corresponding pressure-equalizing main body, and a branch switch control unit is installed on the pressure-equalizing input branch pipe; in some embodiments, the branch switch control unit adopts a cut-off valve, specifically, a second cut-off valve 19 is installed on the first pressure-equalizing input branch pipe 15, a fourth cut-off valve 20 is installed on the second pressure-equalizing input branch pipe 16, and a sixth cut-off valve 21 is installed on the third pressure-equalizing input branch pipe 17).

[0041] The pressure equalizing device has at least three pressure equalizing stages for increasing the pressure in the hot blast furnace in a step-by-step manner; the pressure equalizing structures for implementing each pressure equalizing stage in the pressure equalizing device include a corresponding partial pipe section of the main pipeline, a main pipeline switch control unit, a pressurizing unit and a gas storage unit, the pressurizing unit is connected in series with the gas storage unit (for example, the first gas storage tank 22 is connected in series with the first compressor 23, the second gas storage tank 8 is connected in series with the second compressor 7, and the third gas storage tank 11 is connected in series with the third compressor 10), and the gas storage units of each pressure equalizing structure are connected to the corresponding pressure equalizing input branch pipe.

[0042] In some embodiments, during the last pressure equalization stage of the pressure equalization device, when the pressure inside the hot blast furnace reaches the target value, the pressure difference on both sides of the cold air valve is less than the valve opening threshold, the cold air valve opens, and the branch pipe switch control unit is closed, wherein the cold air valve is arranged on the pipe that transports cold air to the hot blast furnace.

[0043] In some embodiments, the pressure equalizing device has three pressure equalizing stages for increasing the pressure in the hot blast furnace in a step-by-step manner, and the pressure of the gas storage unit in the pressure equalizing structure implementing each pressure equalizing stage in the pressure equalizing device increases sequentially.

[0044] Each gas tank is equipped with a pressure sensor for detecting its internal pressure. A pressure relief valve is set on the gas tank. When the pressure inside the tank exceeds a certain value, the pressure is automatically relieved to ensure the safety of the gas tank. Each hot air furnace is equipped with a pressure sensor on the cold air inlet pipe. Pressure differential metering is designed on both sides of the cold air valve. Pressure detection is set in the hot air furnace and interlocked with the pressure equalizing valve. When the pressure in the hot air furnace reaches a specific value, the relevant valves are opened or closed.

[0045] During operation, after No. 1 hot blast furnace supplies air for 45 minutes, it switches to No. 2 hot blast furnace for supplying air, and after No. 2 hot blast furnace supplies air for 45 minutes, it switches to No. 3 hot blast furnace for supplying air. The working status of the hot blast furnace switches between "supplying air", "changing furnaces" and "burning furnaces", but there is always a hot blast furnace supplying air at any time, which means that the blast furnace is supplied with air continuously. When the combustion of hot blast furnace No. 1 is completed and it is necessary to change the furnace for air supply, the pressure of hot blast furnace No. 1 must be equalized first. During the 7 minutes of pressure equalization, hot blast furnace No. 3 supplies air to the blast furnace. If it is not external pressure equalization, the existing technology provides two operating methods at this time: 1) The air volume of the blower remains unchanged, and a part of the air volume supplied to the blast furnace is not heated by hot blast furnace No. 3 and sent to the blast furnace, but is divided to hot blast furnace No. 1 as pressure equalization gas. At this time, the air supply to the blast furnace is reduced, which will definitely affect the production of the blast furnace; 2) The air volume of the blower is adjusted to ensure that the air volume sent to the blast furnace after being heated by hot blast furnace No. 3 remains unchanged, and the air volume required for pressure equalization of hot blast furnace No. 1 is increased. This operation is achieved by adjusting the blower pressure. Although the adjustment time can be made very short now, the production of the blast furnace will still fluctuate due to changes in air pressure.

[0046] In order to avoid the failure of flue gas pressure equalization affecting blast furnace production, the original pressure equalization valve needs to be retained, and the pressure equalization device adopts the external pressure equalization process. When the No. 1 hot blast furnace is pressure equalized, the air volume and air pressure of the No. 3 hot blast furnace will not be affected at all. In the event of a failure of the independent pressure equalization device, production can still be carried out by the original method of using cold air pressure equalization.

[0047] The working principle of the pressure equalization device is as follows: when a hot blast furnace needs to be replaced, the pressure is equalized in sequence through the first gas tank 22, the second gas tank 8, and the third gas tank 11. For example, when the No. 3 hot blast furnace needs to be replaced, the specific operation is to open the third pressure equalization valve 26, open the second cut-off valve 19, and perform the first stage of pressure equalization on the No. 3 hot blast furnace; when the pressure difference between the No. 3 hot blast furnace and the first gas tank 22 is less than 0.2MPa, close the second cut-off valve 19, open the fourth cut-off valve 20, and perform the second stage of pressure equalization on the No. 3 hot blast furnace; when the pressure difference between the No. 3 hot blast furnace and the second gas tank 8 is less than 2.0MPa, close the fourth cut-off valve 20, open the sixth cut-off valve 21, and perform the third stage of pressure equalization on the No. 3 hot blast furnace; when the pressure difference on both sides of the third cold air valve is less than 0.01MPa, close the sixth cut-off valve 21 to complete the pressure equalization, open the third cold air valve to start supplying air to the blast furnace, and complete the furnace replacement.

[0048] In one embodiment, if the No. 3 hot blast furnace needs to be pressure-equalized, the pressure is equalized in sequence through the first gas storage tank 22 (the internal pressure of the first gas storage tank 22 is 0.4MPa), the second gas storage tank 8 (the internal pressure of the second gas storage tank 8 is 0.6MPa), and the third gas storage tank 11 (the internal pressure of the third gas storage tank 11 is 0.7MPa). Assuming that the cold air pressure is 0.45MPa, the valve opening pressure difference of the cold air valve is less than 0.01MPa, so the pressure equalization of the No. 3 hot blast furnace must reach at least 0.44MPa. The specific operation is to open the third pressure equalizing valve 26, open the second shut-off valve 19, and perform the first stage of pressure equalization on the No. 3 hot blast stove; when the pressure difference between the No. 3 hot blast stove and the first gas storage tank 22 is less than 0.2MPa (that is, when the pressure inside the No. 3 hot blast stove reaches 0.2MPa), close the second shut-off valve 19, open the fourth shut-off valve 20, and perform the second stage of pressure equalization on the No. 3 hot blast stove; when the pressure difference between the No. 3 hot blast stove and the second gas storage tank 8 is less than 2.0MPa (that is, when the pressure inside the No. 3 hot blast stove reaches 0.4MPa), close the fourth shut-off valve 20, open the sixth shut-off valve 21, and perform the third stage of pressure equalization on the No. 3 hot blast stove; when the pressure difference on both sides of the third cold air valve is less than 0.01MPa (that is, when the pressure inside the No. 3 hot blast stove reaches 0.44MPa), close the sixth shut-off valve 21 to complete the pressure equalization; open the third cold air valve to start supplying air to the blast furnace, and complete the furnace changing operation.

[0049] The replacement principle of hot blast stove No. 1 and hot blast stove No. 2 is the same as that of hot blast stove No. 3, and will not be repeated here.

[0050] As can be seen from the above, the commonly used pressure equalization method is to use the cold air produced by the blower to directly equalize the pressure. Since the pressure of the equalized gas provided by the blower is consistent with the final air supply pressure, the flow rate is slow and time-consuming in the later stage of pressure equalization. However, this pressure equalization device is equipped with gas storage tanks with different pressures, which store sufficient medium and high pressure air, so that the pressure equalization pipeline and the hot air furnace always maintain a high pressure difference, and can equalize the pressure with a large flow rate, so that the pressure equalization time can be greatly reduced, that is, the furnace change time is reduced, which is conducive to extending the air supply and furnace burning time, and increasing the utilization rate of the hot air furnace.

[0051] The pressure equalizing device of the present invention realizes a step-by-step increase in the pressure in the hot blast furnace by setting at least three pressure equalizing stages and adopting an independent pressure equalizing structure (including a partial pipe section of the main pipeline, a main pipeline switch control unit, a pressurizing unit and a gas storage unit) in each pressure equalizing stage. This design can evenly adjust the pressure inside and outside the hot blast furnace, and the furnace changing operation does not disturb the air volume entering the furnace, which can effectively avoid the interference of sudden pressure changes on the operation in the furnace, thereby ensuring a smooth furnace changing process, and will not cause fluctuations in the operation of the hot blast furnace, and thus will not affect the blast furnace smelting.

[0052] The pressurizing unit and gas storage unit of the pressure equalizing device of the present invention are designed in series, realizing the internal circulation pressurizing function of blast furnace flue gas instead of relying on an external air compressor to provide a gas source. This design not only reduces the initial investment cost of the equipment, but also reduces the land demand for additional air compressors and the energy consumption and maintenance costs in the later operation, thereby reducing the overall production cost and control cost.

[0053] The pressure equalizing device of the present invention connects the flue gas output end of the hot blast furnace with the pressure equalizing main body, so that the waste heat flue gas generated by the blast furnace can be fully recovered and used in the pressure equalizing process. This resource utilization method effectively reduces the external energy consumption in the blast furnace ironmaking process, improves the energy utilization efficiency, and has a significant energy-saving and environmental protection effect.

[0054] In addition, since the pressure equalizing pipe is relatively small, when the pressure difference between the hot blast furnace and the pressure equalizing pipe is large, the noise during the pressure equalizing process will be very loud, and when the pressure difference is not large enough, the pressure equalizing time will become very long. In order to solve this problem, the present invention adopts a step-by-step pressurization method, by arranging multiple compressors and gas storage tanks in series to pressurize the flue gas. The gas storage unit in each pressure equalizing stage can provide flue gases of different pressures, which are transported to the hot blast furnace through the pressure equalizing pipe, so that the pressure difference between the hot blast furnace and the pressure equalizing pipe is always roughly controlled within 0.2MPa. Under the premise of achieving rapid pressure equalization, the noise pollution is reduced as much as possible, the pressure equalization efficiency is improved, the speed of the pressure equalization process is accelerated, and the operating efficiency of the hot blast furnace pressure equalization system is further optimized.

[0055] The foregoing description of specific exemplary embodiments of the present invention is for the purpose of illustration and demonstration. These descriptions are not intended to limit the present invention to the precise form disclosed, and it is clear that many changes and variations can be made based on the above teachings. The purpose of selecting and describing the exemplary embodiments is to explain the specific principles of the present invention and its practical application, so that those skilled in the art can realize and utilize various different exemplary embodiments of the present invention and various different selections and changes. The scope of the present invention is intended to be limited by the claims and their equivalents.

Claims

1. A pressure equalizing device, characterized in that: include: The pressure-equalizing main body part includes a main pipeline, a main pipeline switch control unit, a pressurizing unit and a gas storage unit; the main pipeline switch control unit, the pressurizing unit and the gas storage unit are provided in a certain number and are all provided on the main pipeline, wherein the input end of the main pipeline is connected to the smoke output end of the hot blast stove; The hot blast furnace connecting pipeline includes a pressure equalizing main pipe and a plurality of pressure equalizing valves, the pressure equalizing main pipe has a pressure equalizing output branch pipe and a pressure equalizing input branch pipe, and the number of the pressure equalizing output branch pipe and the pressure equalizing input branch pipe is a plurality, wherein the pressure equalizing output branch pipe is connected with the corresponding hot blast furnace, the pressure equalizing valve is arranged on the corresponding pressure equalizing output branch pipe, the pressure equalizing input branch pipe is connected with the corresponding gas storage unit of the pressure equalizing main part, and the pressure equalizing input branch pipe is provided with a branch pipe switch control unit; The pressure equalizing device has at least three pressure equalizing stages for increasing the pressure in the hot blast furnace in a step-by-step manner; the pressure equalizing structures for implementing each pressure equalizing stage in the pressure equalizing device include a corresponding partial pipe section of the main pipeline, a main pipeline switch control unit, a pressurizing unit and an air storage unit, the pressurizing unit is connected in series with the air storage unit, and the air storage unit of each of the pressure equalizing structures is connected to the corresponding pressure equalizing input branch pipe.

2. The pressure equalizing device according to claim 1, characterized in that: During the last pressure equalization stage of the pressure equalization device, when the pressure inside the hot blast furnace reaches the target value, the pressure difference on both sides of the cold air valve is less than the valve opening threshold, the cold air valve is opened, and the branch pipe switch control unit is closed, wherein the cold air valve is arranged on the pipe that transports cold air to the hot blast furnace.

3. The pressure equalizing device according to claim 1, characterized in that: The main pipeline includes at least three main pipeline segments, and the number of the main pipeline segments is equal to the number of the pressure equalizing stages of the pressure equalizing device.

4. The pressure equalizing device according to claim 3, characterized in that: According to the order in which the flue gas in each of the main pipeline segments flows through the pipeline nodes, the main pipeline switch control unit, the pressurizing unit and the gas storage unit are sequentially provided at different pipeline nodes on each of the main pipeline segments.

5. The pressure equalizing device according to claim 1, characterized in that: The main pipeline switch control unit includes a cut-off valve.

6. The pressure equalizing device according to claim 1, characterized in that: The branch pipe switch control unit includes a cut-off valve.

7. The pressure equalizing device according to claim 1, characterized in that: The number of the hot blast furnaces is three.

8. The pressure equalizing device according to claim 1, characterized in that: The pressure equalizing device has three pressure equalizing stages for increasing the pressure in the hot blast stove in a step-by-step manner, and the pressure of the gas storage unit in the pressure equalizing structure implementing each pressure equalizing stage in the pressure equalizing device increases sequentially.

9. A pressure equalization method, characterized in that: The pressure equalizing device according to any one of claims 1 to 8 is implemented, comprising the following steps: First, the flue gas in the hot blast furnace is passed into the pressure-equalizing main body part from the input end of the main pipe, and the pressure-equalizing main body part includes the main pipe, the main pipe switch control unit, the pressurizing unit and the gas storage unit; the main pipe switch control unit, the pressurizing unit and the gas storage unit are provided in a certain number and are all provided on the main pipe, wherein the input end of the main pipe is connected with the flue gas output end of the hot blast furnace; Then, each pressure equalizing structure in the pressure equalizing device is used to sequentially implement the corresponding pressure equalizing stage, wherein each pressure equalizing structure includes a corresponding partial pipe section of the main pipeline, a main pipeline switch control unit, a pressurizing unit and a gas storage unit, the pressurizing unit is connected in series with the gas storage unit, and the gas storage unit of each pressure equalizing structure is connected with the corresponding pressure equalizing input branch pipe, so that the pressure-equalizing flue gas output by the gas storage unit of the pressure equalizing structure in each pressure equalizing stage enters the corresponding pressure equalizing input branch pipe; The pressure-equalizing flue gas in the pressure-equalizing input branch pipe is passed through the hot blast furnace connecting pipeline and output from the pressure-equalizing input branch pipe to the corresponding hot blast furnace, wherein the hot blast furnace connecting pipeline includes a pressure-equalizing main pipe and a plurality of pressure-equalizing valves, the pressure-equalizing main pipe has the pressure-equalizing output branch pipe and the pressure-equalizing input branch pipe, and the number of the pressure-equalizing output branch pipes and the pressure-equalizing input branch pipes is a plurality, wherein the pressure-equalizing output branch pipe is connected with the corresponding hot blast furnace, the pressure-equalizing valve is arranged on the corresponding pressure-equalizing output branch pipe, the pressure-equalizing input branch pipe is connected with the corresponding gas storage unit of the pressure-equalizing main part, and the pressure-equalizing input branch pipe is provided with a branch switch control unit; the pressure in the hot blast furnace is increased stepwise to the target value through at least three pressure-equalizing stages.

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