Blast furnace charging bucket pressure equalizing system convenient for overhauling pressure equalizing gas pipeline

Abstract

The utility model discloses a blast furnace charging bucket pressure-equalizing system convenient for overhauling a pressure-equalizing gas pipeline. The blast furnace charging bucket pressure-equalizing system comprises a clean gas pipeline, the pressure-equalizing gas pipeline, a charging bucket connecting pipe and a charging bucket which are communicated in sequence, a first sealing stop valve is arranged on the clean gas pipeline; the pressure-equalizing gas pipeline is connected with a nitrogen purging pipeline, and the nitrogen purging pipeline is provided with a nitrogen purging valve; the pressure-equalizing gas pipeline is also connected with a first blow-off valve; a second sealing stop valve, a pressure equalizing valve and a tank inlet valve are arranged on the material tank connecting pipe; one section of the material tank connecting pipe between the pressure equalizing valve and the tank inlet valve is also communicated with a bleeder, a second bleeder valve is arranged on the bleeder, the section of the material tank connecting pipe is also connected with a pressure equalizing nitrogen pipeline, and a nitrogen cut-off valve is arranged on the pressure equalizing nitrogen pipeline; and a material flow valve and a lower sealing valve are arranged on a discharging pipe at the bottom of the material tank. By using the pressure equalizing system provided by the utility model, the problem of gas leakage can be effectively solved without stopping production, and the nitrogen consumption is reduced as much as possible.

Description

Technical Field

[0001] This utility model relates to the field of blast furnace smelting equipment, and in particular to a blast furnace charge tank pressure equalization system that facilitates the maintenance of pressure equalization gas pipelines. Background Technology

[0002] The design pressure range for the blast furnace top is 0.12–0.25 MPa (gauge pressure). During normal production, the pressure inside the furnace is much higher than atmospheric pressure. To ensure the smooth entry of the charge into the furnace, the pressure in the charging tank must be roughly equal to the pressure inside the furnace. Therefore, gas or nitrogen is typically used for equalization of the charging tank. For gas equalization, high-pressure gas contains corrosive gases such as sulfides and halides, making the equalization pipeline prone to leaks and holes. This not only affects production safety but also leads to poor equalization results. If a leak is found in the equalization gas pipeline during the blast furnace charging tank equalization process, the furnace must be shut down immediately, the gas supply cut off, and valves near the leak point closed. Since the blast furnace is a continuous production facility, stopping production to address this issue would result in significant waste. For nitrogen equalization, because nitrogen is an inert gas that does not burn or support combustion, using nitrogen for equalization can effectively reduce the risk of fire or explosion caused by gas leaks. However, nitrogen is more expensive than coal gas. If nitrogen is relied upon for pressure equalization in the long term, nitrogen consumption will increase significantly, thereby increasing production costs.

[0003] Therefore, there is an urgent need to develop a pressure equalization scheme that can effectively solve the leakage problem without stopping production and minimize nitrogen consumption when the pressure equalization gas pipeline of the blast furnace charge tank is ruptured and leaking. Utility Model Content

[0004] The purpose of this invention is to provide a blast furnace feed tank pressure equalization system that facilitates the maintenance of pressure equalization gas pipelines. It can repair leaks in the pressure equalization gas pipelines by adjusting and controlling relevant valves, avoiding production shutdowns. At the same time, it can flexibly switch between gas equalization and nitrogen equalization by adjusting and controlling relevant valves, which helps to shorten the nitrogen equalization time and thus save costs.

[0005] The technical solution to achieve the purpose of this utility model is: a blast furnace material tank pressure equalization system that facilitates the maintenance of pressure equalization gas pipelines, comprising a clean gas pipeline, a pressure equalization gas pipeline, a material tank connecting pipe, and a material tank connected in sequence; a first sealing shut-off valve is provided on the clean gas pipeline; a nitrogen purging pipeline is connected to the pressure equalization gas pipeline, and a nitrogen purging valve is provided on the nitrogen purging pipeline; a first vent valve is also connected to the pressure equalization gas pipeline; a second sealing shut-off valve, a pressure equalization valve, and an inlet valve are sequentially provided on the material tank connecting pipe along the direction from the pressure equalization gas pipeline to the material tank; a section of the material tank connecting pipe between the pressure equalization valve and the inlet valve is also connected to a vent pipe, and a second vent valve is provided on the vent pipe; a pressure equalization nitrogen pipeline is also connected to this section of the material tank connecting pipe, and a nitrogen shut-off valve is provided on the pressure equalization nitrogen pipeline; a material flow valve and a lower sealing valve are provided on the bottom discharge pipe of the material tank.

[0006] Using the blast furnace charge tank pressure equalization system of this utility model, the pressure equalization gas pipeline can be safely repaired without stopping production by adjusting and controlling the relevant valves, thereby solving the gas leakage problem. At the same time, the relevant valves can also be adjusted and controlled to flexibly switch between gas pressure equalization and nitrogen pressure equalization, which can minimize the time of nitrogen pressure equalization and reduce the consumption caused by nitrogen pressure equalization.

[0007] Furthermore, multiple gas alarms are installed around the pressure equalization gas pipeline to issue alarm signals when the carbon monoxide concentration is less than 24 ppm.

[0008] Preferably, there are two tank connection pipes. The starting ends of these two tank connection pipes are connected to the end of the equalizing gas pipeline. The ends of the two tank connection pipes are respectively connected to the left and right sides of the tank to ensure uniform distribution of gas and effective pressure balance within the tank. Furthermore, the main pipe of the equalizing nitrogen pipeline is connected to the two tank connection pipes via two branch pipes, and each branch pipe is equipped with a nitrogen shut-off valve.

[0009] The first sealing shut-off valve is preferably composed of two valves, such as a butterfly valve and a blind valve, to achieve reliable shut-off and sealing functions and ensure operational safety.

[0010] The second sealing shut-off valve is preferably composed of two valves, such as a pressure equalizing shut-off valve and a slide gate valve. The pressure equalizing shut-off valve can be a ball valve, a butterfly valve, or the like, to achieve reliable shut-off and sealing functions and ensure operational safety.

[0011] Furthermore, the material tank connecting pipe is also connected to the gas recovery box via a gas recovery pipeline, and the gas recovery pipeline is equipped with a recovery valve and a recovery shut-off valve. Attached Figure Description

[0012] Figure 1 This is a simplified structural diagram of the blast furnace charge tank pressure equalization system for convenient maintenance of pressure equalization gas pipelines, as described in an embodiment of this utility model. Detailed Implementation

[0013] The preferred embodiment of the blast furnace charge tank pressure equalization system of the present invention, which facilitates maintenance of pressure equalization gas pipelines, is described in detail below with reference to the accompanying drawings.

[0014] A pressure equalization system for blast furnace feed tanks, facilitating the maintenance of pressure equalization gas pipelines, includes a clean gas pipeline 10, a pressure equalization gas pipeline 20, a feed tank connecting pipe 30, and a feed tank 40 connected in sequence. A first sealing shut-off valve 11 is installed on the clean gas pipeline 10. A nitrogen purging pipeline 50 is connected to the pressure equalization gas pipeline 20, and a nitrogen purging valve 51 is installed on the nitrogen purging pipeline 50. A first vent valve 21 is also connected to the pressure equalization gas pipeline 20. A pressure equalization gas system is provided along the pressure equalization gas pipeline 20 on the feed tank connecting pipe 30. A second sealing shut-off valve 31, a pressure equalization valve 32, and an inlet valve 33 are sequentially arranged from 0 to the material tank 40; a section of the material tank connecting pipe 30 between the pressure equalization valve 32 and the inlet valve 33 is also connected to a vent pipe 300, a second vent valve 301 is provided on the vent pipe 300, and a pressure equalization nitrogen pipeline 60 is also connected to this section of the material tank connecting pipe 30, a nitrogen shut-off valve 61 is provided on the pressure equalization nitrogen pipeline 60; a material flow valve 71 and a lower sealing valve 72 are provided on the bottom discharge pipe 70 of the material tank 40.

[0015] The bottom unloading pipe 70 of the material tank 40 is connected to the top of the blast furnace.

[0016] Multiple gas alarms 80 are installed around the pressure equalization gas pipeline 20 to issue an alarm signal when the carbon monoxide concentration is less than 24 ppm.

[0017] There are two tank connection pipes 30. The starting ends of these two tank connection pipes 30 are connected to the end of the pressure equalizing gas pipeline 20. The ends of the two tank connection pipes 30 are respectively connected to the left and right sides of the tank 40 to ensure uniform distribution of gas and effective pressure balance within the tank 40. The pressure equalizing nitrogen pipeline 60 includes a main pipe 601 and two branch pipes 602. The main pipe 601 is connected to the two tank connection pipes 30 through the two branch pipes 602, and each of the two branch pipes 602 is equipped with a nitrogen shut-off valve 61.

[0018] The first sealing shut-off valve 11 is composed of a butterfly valve 111 and a blind valve 112.

[0019] The second sealing shut-off valve 31 is composed of a pressure equalization shut-off valve 311 and a slide gate valve 312 (e.g., a manual slide gate valve).

[0020] During blast furnace production, when a leak is found in the pressure equalization gas pipeline 20, the following steps can be taken to repair the leak in time: (1) First, operate the blast furnace taphole to inject gas, then reduce the air pressure of the blast furnace to reduce the top pressure to below 0.04 MPa, and then close the first sealing shut-off valve 11 on the clean gas pipeline 10 to cut off the gas supply. The blast furnace taphole is to prevent the blast furnace from entering a shutdown state at any time if the nitrogen pressure equalization is not successfully switched or if a fault occurs during the switch. The blast furnace is to reduce the air pressure in the connecting pipeline between the treasury and the blast furnace. Otherwise, the excessive air pressure will cause the lower sealing valve to fail to close. (2) Close the material flow valve 71 and the lower sealing valve 72 at the bottom of the treasury 40, and keep the second sealing shut-off valve 31, the pressure equalization valve 32 and the second vent valve 33 on the treasury connecting pipe 30 in the open state to depressurize the pressure equalization gas pipeline 20, so as to avoid the pressure in the pressure equalization gas pipeline 20 being too high and causing the first sealing shut-off valve 11 to be difficult to close. (3) Close the second sealing shut-off valve 31 on the material tank connecting pipe 30. At this time, the pressure equalization gas pipeline 20 is completely disconnected from the material tank 40 and the blast furnace. Then open the nitrogen shut-off valve 61 on the pressure equalization nitrogen pipeline 60 to switch the pressure equalization mode of the material tank 40 from gas pressure equalization to nitrogen pressure equalization. (4) Next, open the first vent valve 21 on the pressure equalization gas pipeline 20, and then open the nitrogen purging valve 51 on the nitrogen purging pipeline 50 to introduce N2 into the pressure equalization gas pipeline 20, so as to realize the pressure equalization gas pipeline 20. (5) When the CO content around the pressure equalization gas pipeline 20 drops to a safe level, hot work (e.g., welding) is carried out on the pressure equalization gas pipeline 20 to ensure the safety of the repair operation; (6) After the pressure equalization gas pipeline 20 is repaired, the pressure equalization mode of the material tank 40 is switched back to gas pressure equalization by closing the nitrogen shut-off valve 61 on the pressure equalization nitrogen pipeline 60 and opening the first sealing shut-off valve 11, the second sealing shut-off valve 31, the pressure equalization valve 32 and the tank inlet valve 33.

[0021] Using the blast furnace charge tank pressure equalization system of this utility model, leaks in the pressure equalization gas pipeline 20 can be safely repaired without stopping production, thereby solving the gas leakage problem. At the same time, it can minimize the time for nitrogen pressure equalization and reduce the consumption caused by nitrogen pressure equalization.

[0022] Furthermore, the material tank connecting pipe 30 is also connected to the gas recovery box 100 via a gas recovery pipe 90. The gas recovery pipe 90 is equipped with a recovery valve 91 and a recovery shut-off valve 92, enabling the gas in the equalizing gas pipe 20 and the material tank connecting pipe 30 to be recovered into the gas recovery box 100 via the gas recovery pipe 90, thus avoiding waste. Of course, this invention can also omit the gas recovery pipe 90, the gas recovery box 100, the recovery valve 91, and the recovery shut-off valve 92.

[0023] Of course, the gas alarm 80 may not be installed around the equalizing gas pipeline 20; instead, other methods such as electrochemical sensors or infrared absorption methods can be used to monitor the carbon monoxide concentration around the equalizing gas pipeline 20. Only one tank connection pipe 30 may be installed. The first sealing shut-off valve 11 and the second sealing shut-off valve 31 only need to achieve good shut-off and sealing effects; the type and number of valve combinations can be, but are not limited to, the specific types and numbers described in the above embodiments.

[0024] The above description is merely an embodiment of this utility model and does not limit the patent scope of this utility model. Any equivalent structural transformations made using the content of this utility model specification, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this utility model.

Claims

1. A pressure equalization system for a blast furnace charge tank that facilitates maintenance of a pressure equalization gas pipeline, comprising a clean gas pipeline, a pressure equalization gas pipeline, a charge tank connecting pipe, and a charge tank connected in sequence; wherein a first sealing shut-off valve is provided on the clean gas pipeline; characterized in that: A nitrogen purging pipeline is connected to the pressure equalizing gas pipeline, and a nitrogen purging valve is installed on the nitrogen purging pipeline; a first vent valve is also connected to the pressure equalizing gas pipeline; a second sealing shut-off valve, a pressure equalizing valve, and an inlet valve are sequentially installed on the material tank connecting pipe along the direction from the pressure equalizing gas pipeline to the material tank; a section of the material tank connecting pipe between the pressure equalizing valve and the inlet valve is also connected to a vent pipe, and a second vent valve is installed on the vent pipe; a pressure equalizing nitrogen pipeline is also connected to this section of the material tank connecting pipe, and a nitrogen shut-off valve is installed on the pressure equalizing nitrogen pipeline; a material flow valve and a lower sealing valve are installed on the bottom discharge pipe of the material tank.

2. The blast furnace charge tank pressure equalization system for convenient maintenance of pressure equalization gas pipelines according to claim 1, characterized in that: Multiple gas alarms are installed around the pressure equalization gas pipeline to issue alarm signals when the carbon monoxide concentration is less than 24 ppm.

3. The blast furnace charge tank pressure equalization system for convenient maintenance of pressure equalization gas pipelines according to claim 1, characterized in that: There are two material tank connecting pipes. The starting ends of these two material tank connecting pipes are connected to the end of the pressure equalizing gas pipeline, and the ends of the two material tank connecting pipes are respectively connected to the left and right sides of the material tank.

4. The blast furnace charge tank pressure equalization system for convenient maintenance of pressure equalization gas pipelines according to claim 3, characterized in that: The main pipe of the equalizing nitrogen pipeline is connected to the connecting pipes of the two material tanks through two branch pipes, and the nitrogen shut-off valve is installed on each of the two branch pipes.

5. The blast furnace charge tank pressure equalization system for convenient maintenance of pressure equalization gas pipelines according to claim 1, characterized in that: The first sealing shut-off valve is composed of two valves.

6. The blast furnace charge tank pressure equalization system for convenient maintenance of pressure equalization gas pipelines according to claim 1, characterized in that: The second sealing shut-off valve is composed of two valves.

7. The blast furnace charge tank pressure equalization system for convenient maintenance of pressure equalization gas pipelines according to claim 1, characterized in that: The material tank connecting pipe is also connected to the gas recovery box via a gas recovery pipeline, which is equipped with a recovery valve and a recovery shut-off valve.

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