Method and system for controlling furnace top pressure of blast furnace

Abstract

The blast furnace top pressure control method comprises the steps that when it is detected that the blast furnace top pressure is larger than or equal to a first set pressure value in the blast furnace top pressure rising process, after a first bypass valve connected with a blast furnace top gas pressure turbine (TRT) is controlled to be opened to a first preset opening degree, the first bypass valve is opened to a second preset opening degree; adjusting the opening degree of a stationary blade of the TRT according to the furnace top pressure of the blast furnace; wherein the TRT and the first bypass valve are both connected in a blast furnace gas pipe network, the first end of the first bypass valve is connected with the first end of the TRT through a gas pipe, and the second end of the first bypass valve is connected with the second end of the TRT through the gas pipe. And the stable furnace top pressure can be effectively maintained, the furnace top blow-off valve is prevented from being burst open, and the stability and the gas utilization efficiency of the blast furnace are improved.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of blast furnace automation control, and in particular to a method and system for controlling blast furnace top pressure. Background Art

[0002] Under normal production conditions of the blast furnace, the furnace top pressure is controlled by the blast furnace gas recovery turbine unit (TRT) through the opening of the stator blades. The pressure regulating valve group is only used as an emergency control device for the furnace top pressure control, and only performs auxiliary adjustments when the TRT stator blades cannot adjust the top pressure. Under normal production conditions, the pressure inside the blast furnace is relatively stable. However, when abnormal airflows such as pipelines occur in the blast furnace, the instantaneous amount of gas in the blast furnace will increase sharply. When the TRT stator blades are fully opened, the amount of gas generated by the blast furnace pipeline cannot be quickly discharged, causing the blast furnace top pressure to rise rapidly. After reaching the safety interlock value set by the furnace top relief valve, the furnace top relief valve automatically opens, causing major safety and environmental incidents. Summary of the invention

[0003] The embodiment of the present invention provides a method and system for controlling the top pressure of a blast furnace, which can effectively maintain a stable top pressure, prevent the top relief valve from being blown open, and improve the stability of the blast furnace and the gas utilization efficiency.

[0004] According to a first aspect of the present invention, there is provided a method for controlling a blast furnace top pressure, comprising:

[0005] When it is detected that the blast furnace top pressure is greater than or equal to a first set pressure value during the rising process of the blast furnace top pressure, the first bypass valve connected to the TRT is controlled to open to a first preset opening, and the opening of the stationary blades of the TRT is adjusted according to the blast furnace top pressure; wherein the TRT and the first bypass valve are both connected to the blast furnace gas pipeline network, the first end of the first bypass valve is connected to the first end of the TRT through the gas pipe, and the second end of the first bypass valve is connected to the second end of the TRT through the gas pipe.

[0006] Optionally, controlling the first bypass valve connected to the TRT to open to a first preset opening degree includes:

[0007] If the blast furnace top pressure is greater than or equal to the first set pressure value and less than or equal to the second set pressure value, the first bypass valve is controlled to open to 24%-27% opening;

[0008] If the blast furnace top pressure is greater than or equal to the third set pressure value and less than or equal to the fourth set pressure value, the first bypass valve is controlled to open to 34%-37% opening;

[0009] If the blast furnace top pressure is greater than or equal to the fifth set pressure value and less than or equal to the sixth set pressure value, the first bypass valve is controlled to open to 44%-47% opening;

[0010] Among them, the first set pressure value is 1.05 times the blast furnace set pressure value, the second set pressure value is 1.07 times the blast furnace set pressure value, the third set pressure value is 1.08 times the blast furnace set pressure value, the fourth set pressure value is 1.1 times the blast furnace set pressure value, the fifth set pressure value is 1.11 times the blast furnace set pressure value, and the sixth set pressure value is 1.13 times the blast furnace set pressure value.

[0011] Optionally, before adjusting the opening of the TRT stator blades according to the blast furnace top pressure, the method further includes:

[0012] If it is detected that the first bypass valve has not operated within a preset time period, the second bypass valve connected to the TRT is controlled to open to a second preset opening; wherein the first end of the second bypass valve is connected to the first end of the TRT through a gas pipe, and the second end of the second bypass valve is connected to the second end of the TRT through a gas pipe.

[0013] Optionally, controlling the second bypass valve connected to the TRT to open to a second preset opening degree includes:

[0014] If the blast furnace top pressure is greater than or equal to the first set pressure value and less than or equal to the second set pressure value, the second bypass valve is controlled to open to 27%-30% opening;

[0015] If the blast furnace top pressure is greater than or equal to the third set pressure value and less than or equal to the fourth set pressure value, the second bypass valve is controlled to open to 37%-40% opening;

[0016] If the blast furnace top pressure is greater than or equal to the fifth set pressure value and less than or equal to the sixth set pressure value, the second bypass valve is controlled to open to 49%-52% opening;

[0017] Among them, the first set pressure value is 1.05 times the blast furnace set pressure value, the second set pressure value is 1.07 times the blast furnace set pressure value, the third set pressure value is 1.08 times the blast furnace set pressure value, the fourth set pressure value is 1.1 times the blast furnace set pressure value, the fifth set pressure value is 1.11 times the blast furnace set pressure value, and the sixth set pressure value is 1.13 times the blast furnace set pressure value.

[0018] Optionally, when it is detected that the blast furnace top pressure is greater than or equal to a first set pressure value during the process of decreasing the blast furnace top pressure, the first bypass valve and / or the second bypass valve are controlled to be reduced to a third preset opening, and the opening of the stationary blades of the TRT is adjusted according to the blast furnace top pressure.

[0019] Optionally, if the blast furnace top pressure is greater than or equal to the fifth set pressure value and less than or equal to the sixth set pressure value, the first bypass valve is controlled to be closed to an opening of 46%-43%;

[0020] If the blast furnace top pressure is greater than or equal to the third set pressure value and less than or equal to the fourth set pressure value, the first bypass valve and the second bypass valve are controlled to be closed to 36%-33% opening;

[0021] If the blast furnace top pressure is greater than or equal to the first set pressure value and less than or equal to the second set pressure value, the first bypass valve and the second bypass valve are controlled to be closed to 0 opening.

[0022] Optionally, when it is detected that the blast furnace top pressure is greater than or equal to a first set pressure value during a decrease in blast furnace top pressure, if the first bypass valve fails, the second bypass valve is controlled to be reduced to a fourth preset opening, and the opening of the stationary blades of the TRT is adjusted according to the blast furnace top pressure, wherein, under the same top pressure, the fourth preset opening is smaller than the third preset opening.

[0023] Optionally, if the blast furnace top pressure is greater than or equal to the fifth set pressure value and less than or equal to the sixth set pressure value, the second bypass valve is controlled to be closed to an opening of 34%-37%;

[0024] If the blast furnace top pressure is greater than or equal to the third set pressure value and less than or equal to the fourth set pressure value, the second bypass valve is controlled to be closed to an opening of 24%-27%;

[0025] If the blast furnace top pressure is greater than or equal to the first set pressure value and less than or equal to the second set pressure value, the second bypass valve is controlled to close to 0 opening.

[0026] Optionally, the first bypass valve is a double-acting valve, and the second bypass valve is a single-acting valve.

[0027] According to a second aspect of the present invention, there is provided a control system for a blast furnace top pressure, comprising:

[0028] TRT, a first bypass valve and a controller; TRT and the first bypass valve are both connected to the blast furnace gas network, a first end of the first bypass valve is connected to a first end of the TRT through a gas pipe, and a second end of the first bypass valve is connected to a second end of the TRT through a gas pipe;

[0029] The controller is used to detect that when the blast furnace top pressure is greater than or equal to the first set pressure during the rising process of the blast furnace top pressure, it controls the first bypass valve connected to the TRT to open to the first preset opening, and then adjusts the opening of the stationary blades of the TRT according to the blast furnace top pressure.

[0030] The control method of blast furnace top pressure provided by the embodiment of the present invention comprises: when the blast furnace top pressure is detected to be greater than or equal to the first set pressure value during the rising process of the blast furnace top pressure, the first bypass valve connected to the TRT is controlled to open to the first preset opening, and the opening of the stationary blade of the TRT is adjusted according to the blast furnace top pressure; by accurately controlling the blast furnace top pressure, the damage to the blast furnace body caused by excessively high or low pressure can be effectively prevented. Among them, the TRT and the first bypass valve are both connected to the blast furnace gas pipeline network, the first end of the first bypass valve is connected to the first end of the TRT through the gas pipe, and the second end of the first bypass valve is connected to the second end of the TRT through the gas pipe. By using the coordinated regulation of the TRT device and the first bypass valve, the blast furnace gas resources can be used more efficiently. It is applied to the control of the blast furnace top pressure by TRT and the pressure regulating valve group under abnormal furnace conditions of large, medium and small blast furnaces. It can quickly adapt to the changes in the abnormal furnace conditions of the blast furnace, effectively maintain a stable furnace top pressure, prevent the furnace top relief valve from being opened, and improve the stability and gas utilization efficiency of the blast furnace. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a structural schematic diagram of a blast furnace provided by an embodiment of the present invention;

[0032] Figure 2 It is a structural schematic diagram of a control system for blast furnace top pressure provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0033] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0034] The embodiment of the present invention provides a method for controlling the top pressure of a blast furnace. Figure 1 is a schematic diagram of the structure of a blast furnace provided by an embodiment of the present invention, with reference to Figure 1 , the control method of blast furnace top pressure includes:

[0035] When it is detected that the pressure at the top of the blast furnace 60 is greater than or equal to the first set pressure value during the rising process, the first bypass valve 20 connected to the TRT10 is controlled to open to the first preset opening, and the opening of the stationary blades of the TRT10 is adjusted according to the pressure at the top of the blast furnace 60; wherein, the TRT10 and the first bypass valve 20 are both connected to the blast furnace gas pipeline network, the first end of the first bypass valve 20 is connected to the first end of the TRT10 through the gas pipe 30, and the second end of the first bypass valve 20 is connected to the second end of the TRT10 through the gas pipe 30.

[0036] Among them, the first set pressure value is usually set based on the optimal balance point between the safety and production efficiency of the blast furnace 60, and is measured by a pressure gauge installed on the top of the blast furnace 60. The opening of the stationary blades of TRT10 refers to the opening degree or angle of the static blades (or adjustable guide vanes). In TRT10, the stationary blades are usually designed to be adjustable so that the gas flow through the turbine can be adjusted as needed. The larger the opening of the stationary blades of TRT10, the greater the gas flow allowed to pass, and the speed and power generation of the turbine also increase accordingly. Conversely, the smaller the opening of the stationary blades of TRT10, the gas flow is limited, and the speed and power generation of the turbine are reduced. The first end is usually the gas inlet. The second end is usually the gas outlet.

[0037] Basic principle: The instantaneous gas volume in blast furnace 60 will increase sharply. When the TRT10 stator blades are fully opened, the gas volume generated by the blast furnace pipeline cannot be quickly discharged, causing the top pressure of blast furnace 60 to rise rapidly. If the bypass valve is opened to a larger opening, it will cause vibration impact on the gas pipeline network and related equipment. In order to stabilize the top pressure of blast furnace 60 and reduce the operating load of the bypass valve, it is determined to use the TRT bypass valve (first bypass valve 20, second bypass valve 40) to preferentially open the valve for adjustment (fixed bypass pressure relief) in conjunction with the TRT10 stator blades to adjust the top pressure.

[0038] Specifically, when the blast furnace 60 is operating normally, the pressure on the top of the blast furnace 60 will gradually increase due to the input of raw materials and the progress of the combustion reaction. When the pressure on the top of the blast furnace 60 rises to a value greater than or equal to a preset first set pressure value, the pressure on the top of the blast furnace 60 is relatively high, which may affect the normal operation of the blast furnace 60 and the effective use of gas resources. The system will automatically control the first bypass valve 20 connected to the TRT10 to open to the first preset opening. After the first bypass valve 20 is opened to the first preset opening, the system will further adjust the opening of the stationary blades of the TRT10 according to the real-time change of the pressure on the top of the blast furnace 60. By accurately adjusting the opening of the stationary blades of the TRT10, the energy of the blast furnace gas can be maximized while maintaining the stability of the pressure on the top of the blast furnace 60.

[0039] The control method of the blast furnace top pressure provided by the embodiment of the present invention comprises: when it is detected that the blast furnace 60 top pressure is greater than or equal to the first set pressure value during the rising process of the blast furnace 60 top pressure, the first bypass valve 20 connected to the TRT10 is controlled to open to the first preset opening, and the opening of the stationary blades of the TRT10 is adjusted according to the blast furnace 60 top pressure; by accurately controlling the blast furnace 60 top pressure, damage to the blast furnace 60 body caused by excessively high or low pressure can be effectively prevented. Among them, the TRT10 and the first bypass valve 20 are both connected to the blast furnace 60 gas pipeline network, the first end of the first bypass valve 20 is connected to the first end of the TRT10 through the gas pipe 30, and the second end of the first bypass valve 20 is connected to the second end of the TRT10 through the gas pipe 30. By using the coordinated adjustment of the TRT10 device and the first bypass valve 20, the blast furnace 60 gas resources can be used more efficiently. It is used in the control of the furnace top pressure of blast furnace 60 by TRT10 and pressure regulating valve group under abnormal furnace conditions of large, medium and small blast furnace 60. It can quickly adapt to the changes of abnormal furnace conditions of blast furnace 60, effectively maintain stable furnace top pressure, prevent the furnace top relief valve from being opened, and improve the stability of blast furnace 60 and gas utilization efficiency.

[0040] Optionally, controlling the first bypass valve 20 connected to the TRT 10 to open to a first preset opening degree includes:

[0041] If the top pressure of the blast furnace 60 is greater than or equal to the first set pressure value and less than or equal to the second set pressure value, the first bypass valve 20 is controlled to open to 24%-27% opening;

[0042] If the top pressure of the blast furnace 60 is greater than or equal to the third set pressure value and less than or equal to the fourth set pressure value, the first bypass valve 20 is controlled to open to 34%-37% opening;

[0043] If the top pressure of the blast furnace 60 is greater than or equal to the fifth set pressure value and less than or equal to the sixth set pressure value, the first bypass valve 20 is controlled to open to 44%-47% opening;

[0044] Among them, the first set pressure value is 1.05 times the set pressure value of blast furnace 60, the second set pressure value is 1.07 times the set pressure value of blast furnace 60, the third set pressure value is 1.08 times the set pressure value of blast furnace 60, the fourth set pressure value is 1.1 times the set pressure value of blast furnace 60, the fifth set pressure value is 1.11 times the set pressure value of blast furnace 60, and the sixth set pressure value is 1.13 times the set pressure value of blast furnace 60.

[0045] Specifically, according to the range of the furnace top pressure, the opening of the first bypass valve 20 connected to the TRT 10 is controlled. If the furnace top pressure of the blast furnace 60 is greater than or equal to the first set pressure value (1.05 times the set pressure value of the blast furnace 60), and less than or equal to the second set pressure value (1.07 times the set pressure value of the blast furnace 60), the first bypass valve 20 is controlled to open to an opening of 24%-27%. If the furnace top pressure of the blast furnace 60 is greater than or equal to the third set pressure value (1.08 times the set pressure value of the blast furnace 60), and less than or equal to the fourth set pressure value (1.1 times the set pressure value of the blast furnace 60), the first bypass valve 20 is controlled to open to an opening of 34%-37%. If the top pressure of the blast furnace 60 is greater than or equal to the fifth set pressure value (1.11 times the set pressure value of the blast furnace 60) and less than or equal to the sixth set pressure value (1.13 times the set pressure value of the blast furnace 60), the first bypass valve 20 is controlled to open to an opening of 44%-47%. The top pressure of the blast furnace 60 is continuously monitored in real time, and the opening of the first bypass valve 20 is adjusted according to the pressure change to keep the top pressure of the blast furnace 60 within a suitable range.

[0046] Optionally, before adjusting the opening of the TRT stator blades according to the top pressure of the blast furnace 60, the method further includes:

[0047] If it is detected that the first bypass valve 20 has not been actuated within a preset time period, the second bypass valve 40 connected to the TRT10 is controlled to open to a second preset opening; wherein a first end of the second bypass valve 40 is connected to a first end of the TRT10 via a gas pipe 30, and a second end of the second bypass valve 40 is connected to a second end of the TRT10 via a gas pipe 30.

[0048] The second preset opening is set according to the actual situation of the top pressure of blast furnace 60 and the expected adjustment effect to ensure the reasonable adjustment of the gas flow rate.

[0049] Specifically, during the operation of the blast furnace 60, the system will continuously monitor the state of the first bypass valve 20 to understand in real time whether the first bypass valve 20 is in an action state (i.e., whether the gas flow rate is being adjusted). Within a preset time, the system will determine whether the first bypass valve 20 has made corresponding actions according to the changes in the top pressure of the blast furnace 60. If the first bypass valve 20 does not move within the preset time of 3 seconds, it means that the first bypass valve 20 has a fault or cannot meet the current adjustment requirements. When it is determined that the first bypass valve 20 is not in action, the system will control the second bypass valve 40 connected to TRT10 to open to the second preset opening. After the second bypass valve 40 is opened, the system will continue to monitor the changes in the top pressure of the blast furnace 60, and adjust the opening of the stationary blades of TRT10 as needed to achieve more accurate pressure control. At the same time, the system will continue to monitor the state of the first bypass valve 20. Once the first bypass valve 20 resumes normal operation, the system may consider closing the second bypass valve 40 and re-controlling the first bypass valve 20 to adjust the gas flow rate. If the first bypass valve 20 does not operate for a long time and the second bypass valve 40 is unable to effectively regulate the gas flow, the system may trigger an alarm mechanism to notify the operator to perform inspection and maintenance.

[0050] Optionally, controlling the second bypass valve 40 connected to the TRT 10 to open to a second preset opening degree includes:

[0051] If the top pressure of the blast furnace 60 is greater than or equal to the first set pressure value, and less than or equal to the second set pressure value, the second bypass valve 40 is controlled to open to 27%-30% opening;

[0052] If the top pressure of the blast furnace 60 is greater than or equal to the third set pressure value and less than or equal to the fourth set pressure value, the second bypass valve 40 is controlled to open to 37%-40% opening;

[0053] If the top pressure of the blast furnace 60 is greater than or equal to the fifth set pressure value and less than or equal to the sixth set pressure value, the second bypass valve 40 is controlled to open to 49%-52% opening;

[0054] Among them, the first set pressure value is 1.05 times the set pressure value of blast furnace 60, the second set pressure value is 1.07 times the set pressure value of blast furnace 60, the third set pressure value is 1.08 times the set pressure value of blast furnace 60, the fourth set pressure value is 1.1 times the set pressure value of blast furnace 60, the fifth set pressure value is 1.11 times the set pressure value of blast furnace 60, and the sixth set pressure value is 1.13 times the set pressure value of blast furnace 60.

[0055] Specifically, when the first bypass valve 20 does not operate within the preset time of 3 seconds, the system will control the second bypass valve 40 to open to the corresponding opening. If the top pressure of the blast furnace 60 is greater than or equal to the first set pressure value (1.05 times the set pressure value of the blast furnace 60) and less than or equal to the second set pressure value (1.07 times the set pressure value of the blast furnace 60), the second bypass valve 40 is controlled to open to an opening of 27%-30%. If the top pressure of the blast furnace 60 is greater than or equal to the third set pressure value (1.08 times the set pressure value of the blast furnace 60) and less than or equal to the fourth set pressure value (1.1 times the set pressure value of the blast furnace 60), the second bypass valve 40 is controlled to open to an opening of 37%-40%. When the top pressure of the blast furnace 60 is greater than or equal to the fifth set pressure value (1.11 times the set pressure value of the blast furnace 60) and less than or equal to the sixth set pressure value (1.13 times the set pressure value of the blast furnace 60), the second bypass valve 40 is controlled to open to an opening of 49%-52%. While controlling the opening of the second bypass valve 40, the system will continuously monitor the changes in the top pressure of the blast furnace 60, and adjust the opening of the second bypass valve 40 or other related parameters as needed to keep the top pressure of the blast furnace 60 within a stable and safe range.

[0056] Optionally, when it is detected that the pressure at the top of blast furnace 60 is greater than or equal to a first set pressure value during a decrease in the pressure at the top of blast furnace 60, the first bypass valve 10 and / or the second bypass valve 40 is controlled to be reduced to a third preset opening, and then the opening of the stationary blades of TRT10 is adjusted according to the pressure at the top of blast furnace 60.

[0057] The third preset opening is pre-set according to system requirements and operating experience, and is intended to influence the change trend of the top pressure of the blast furnace 60 by reducing the opening of the first bypass valve 10 and / or the second bypass valve 40 .

[0058] Specifically, during the process of the pressure on the top of the blast furnace 60 decreasing, the system will determine whether the current pressure is still greater than or equal to the preset first set pressure value. If the pressure on the top of the blast furnace 60 is greater than or equal to the first set pressure value, the system will control the first bypass valve 10 and / or the second bypass valve 40 to be reduced to the third preset opening. After controlling the first bypass valve 10 and / or the second bypass valve 40 to be reduced to the third preset opening, the system will continue to monitor the changes in the pressure on the top of the blast furnace 60, and adjust the opening of the stationary blades of the TRT10 as needed to maintain the stability of the pressure on the top of the blast furnace 60. If the system detects that the first bypass valve 10 and / or the second bypass valve 40 or the stationary blades of the TRT10 cannot operate as expected, or the pressure on the top of the blast furnace 60 continues to exceed the safety range, the system will trigger an alarm mechanism to notify the operator to conduct inspections and repairs.

[0059] Optionally, if the top pressure of the blast furnace 60 is greater than or equal to the fifth set pressure value and less than or equal to the sixth set pressure value, the first bypass valve 10 is controlled to be closed to an opening of 46%-43%;

[0060] If the top pressure of the blast furnace 60 is greater than or equal to the third set pressure value and less than or equal to the fourth set pressure value, the first bypass valve 10 and the second bypass valve 40 are controlled to be closed to 36%-33% opening;

[0061] If the top pressure of the blast furnace 60 is greater than or equal to the first set pressure value and less than or equal to the second set pressure value, the first bypass valve 10 and the second bypass valve 40 are controlled to be closed to zero opening.

[0062] Specifically, when the top pressure of the blast furnace 60 is greater than or equal to the fifth set pressure value (1.11 times the set pressure value of the blast furnace 60) and less than or equal to the sixth set pressure value (1.13 times the set pressure value of the blast furnace 60), the first bypass valve 10 is controlled to be closed to 46%-43% opening. When the top pressure of the blast furnace 60 is greater than or equal to the third set pressure value (1.08 times the set pressure value of the blast furnace 60) and less than or equal to the fourth set pressure value (1.1 times the set pressure value of the blast furnace 60), the first bypass valve 10 and the second bypass valve 40 are controlled to be closed to 36%-33% opening. When the top pressure of the blast furnace 60 is greater than or equal to the first set pressure value (1.05 times the set pressure value of the blast furnace 60) and less than or equal to the second set pressure value (1.07 times the set pressure value of the blast furnace 60), the first bypass valve 10 and the second bypass valve 40 are controlled to be closed to 0 opening.

[0063] Optionally, when it is detected that the top pressure of blast furnace 60 is greater than or equal to the first set pressure value during the process of decreasing the top pressure of blast furnace 60, if the first bypass valve 10 fails, the second bypass valve 40 is controlled to be reduced to a fourth preset opening, and the opening of the stationary blades of TRT10 is adjusted according to the top pressure of blast furnace 60, wherein, under the same top pressure, the fourth preset opening is smaller than the third preset opening.

[0064] The fourth preset opening is set according to the need during the pressure drop of the top of the blast furnace 60, and is usually smaller than the third preset opening under normal circumstances to slow down the pressure drop rate or maintain a certain pressure level.

[0065] Specifically, during the process of the pressure drop at the top of the blast furnace 60, the system will determine whether the current pressure is still greater than or equal to the preset first set pressure value. If the pressure at the top of the blast furnace 60 is greater than or equal to the first set pressure value, the system will detect the state of the first bypass valve 10 to determine whether it is in a normal working state. If the system detects that the first bypass valve 10 fails (such as being unable to open, insufficient opening, or slow response, etc.), it will enter emergency processing. After confirming that the first bypass valve 10 fails, the system will control the second bypass valve 40 to be reduced to a fourth preset opening. After controlling the second bypass valve 40 to be reduced to the fourth preset opening, the system will continue to monitor the changes in the pressure at the top of the blast furnace 60 and adjust the opening of the stationary blades of the TRT10 as needed. If the system detects that the second bypass valve 40 also fails to act as expected, or the pressure at the top of the blast furnace 60 continues to exceed the safety range, the system will trigger an alarm mechanism to notify the operator to perform inspections and repairs.

[0066] Optionally, if the top pressure of the blast furnace 60 is greater than or equal to the fifth set pressure value and less than or equal to the sixth set pressure value, the second bypass valve 40 is controlled to be closed to an opening of 34%-37%;

[0067] If the top pressure of the blast furnace 60 is greater than or equal to the third set pressure value and less than or equal to the fourth set pressure value, the second bypass valve 40 is controlled to be closed to an opening of 24%-27%;

[0068] If the top pressure of the blast furnace 60 is greater than or equal to the first set pressure value and less than or equal to the second set pressure value, the second bypass valve 40 is controlled to be closed to zero opening.

[0069] Specifically, when the top pressure of the blast furnace 60 is greater than or equal to the fifth set pressure value (1.11 times the set pressure value of the blast furnace 60) and less than or equal to the sixth set pressure value (1.13 times the set pressure value of the blast furnace 60), the second bypass valve 40 is controlled to be closed to 34%-37% opening. When the top pressure of the blast furnace 60 is greater than or equal to the third set pressure value (1.08 times the set pressure value of the blast furnace 60) and less than or equal to the fourth set pressure value (1.1 times the set pressure value of the blast furnace 60), the second bypass valve 40 is controlled to be closed to 24%-27% opening. When the top pressure of the blast furnace 60 is greater than or equal to the first set pressure value (1.05 times the set pressure value of the blast furnace) and less than or equal to the second set pressure value (1.07 times the set pressure value of the blast furnace 60), the second bypass valve 40 is controlled to be closed to 0 opening.

[0070] Optionally, the first bypass valve 20 is a double-acting valve, and the second bypass valve 40 is a single-acting valve.

[0071] Specifically, the first bypass valve 20 can perform bidirectional operation; the valve core of the first bypass valve 20 is cylindrical, which can maintain a stable motion trajectory and sealing performance during bidirectional operation; the first bypass valve 20 has two valve platforms. The second bypass valve 40 can only perform unidirectional operation; the valve core of the second bypass valve 40 is conical, which can achieve better sealing effect and flow control during unidirectional operation; the second bypass valve 40 has only one valve platform for controlling unidirectional flow or pressure.

[0072] The embodiment of the present invention provides a control system for blast furnace top pressure. Figure 2 is a schematic diagram of a control system for blast furnace top pressure provided by an embodiment of the present invention, with reference to Figure 2 , the control system of blast furnace top pressure includes:

[0073] TRT10, first bypass valve 20 and controller 50; TRT10 and first bypass valve 20 are both connected to the gas network of blast furnace 60, a first end of the first bypass valve 20 is connected to the first end of TRT10 through the gas pipe 30, and a second end of the first bypass valve 20 is connected to the second end of TRT10 through the gas pipe 30;

[0074] The controller 50 is used to detect that when the pressure at the top of the blast furnace 60 is greater than or equal to the first set pressure during the rising process, it controls the first bypass valve 20 connected to the TRT10 to open to the first preset opening, and then adjusts the opening of the stationary blades of the TRT10 according to the pressure at the top of the blast furnace 60.

[0075] Specifically, during the process of the blast furnace 60 top pressure rising, the controller will determine whether the current top pressure is greater than or equal to the preset first set pressure value. If the blast furnace 60 top pressure is greater than or equal to the first set pressure value, the controller 50 will send an instruction to the first bypass valve 20 to control it to open to the first preset opening. After the first bypass valve 20 is opened to the first preset opening, the controller 50 will continue to monitor the changes in the blast furnace 60 top pressure and adjust the opening of the stationary blades of TRT10 as needed. During the entire control process, the controller 50 will continue to monitor the changes in the blast furnace 60 top pressure and the status of the first bypass valve 20 and the TRT10 stationary blades, and continuously adjust the control strategy as needed. If the controller 50 detects that the first bypass valve 20 cannot act as expected, or the blast furnace 60 top pressure continues to exceed the safety range, the system will trigger an alarm mechanism to notify the operator to check and repair.

[0076] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the present invention can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of the present invention can be achieved, and this document does not limit this.

[0077] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for controlling blast furnace top pressure, characterized in that: include: When it is detected that the blast furnace top pressure is greater than or equal to a first set pressure value during the rising process of the blast furnace top pressure, the first bypass valve connected to the blast furnace gas residual pressure turbine power generation device TRT is controlled to open to a first preset opening, and the opening of the stationary blades of the TRT is adjusted according to the blast furnace top pressure; wherein the TRT and the first bypass valve are both connected to the blast furnace gas pipeline network, the first end of the first bypass valve is connected to the first end of the TRT through a gas pipe, and the second end of the first bypass valve is connected to the second end of the TRT through the gas pipe.

2. The control method according to claim 1, characterized in that: Controlling the first bypass valve connected to the blast furnace gas residual pressure turbine power generation device TRT to open to a first preset opening, comprising: If the blast furnace top pressure is greater than or equal to the first set pressure value and less than or equal to the second set pressure value, the first bypass valve is controlled to open to 24%-27% opening; If the blast furnace top pressure is greater than or equal to the third set pressure value and less than or equal to the fourth set pressure value, the first bypass valve is controlled to open to 34%-37% opening; If the blast furnace top pressure is greater than or equal to the fifth set pressure value and less than or equal to the sixth set pressure value, the first bypass valve is controlled to open to 44%-47% opening; Among them, the first set pressure value is 1.05 times the set pressure value of the blast furnace, the second set pressure value is 1.07 times the set pressure value of the blast furnace, the third set pressure value is 1.08 times the set pressure value of the blast furnace, the fourth set pressure value is 1.1 times the set pressure value of the blast furnace, the fifth set pressure value is 1.11 times the set pressure value of the blast furnace, and the sixth set pressure value is 1.13 times the set pressure value of the blast furnace.

3. The control method according to claim 1, characterized in that: Before adjusting the opening of the TRT stator blades according to the blast furnace top pressure, it also includes: If it is detected that the first bypass valve has not operated within a preset time period, the second bypass valve connected to the TRT is controlled to open to a second preset opening; wherein the first end of the second bypass valve is connected to the first end of the TRT through a gas pipe, and the second end of the second bypass valve is connected to the second end of the TRT through a gas pipe.

4. The control method according to claim 3, characterized in that: Controlling the second bypass valve connected to the TRT to open to a second preset opening degree includes: If the blast furnace top pressure is greater than or equal to the first set pressure value and less than or equal to the second set pressure value, the second bypass valve is controlled to open to 27%-30% opening; If the blast furnace top pressure is greater than or equal to the third set pressure value and less than or equal to the fourth set pressure value, the second bypass valve is controlled to open to 37%-40% opening; If the blast furnace top pressure is greater than or equal to the fifth set pressure value and less than or equal to the sixth set pressure value, the second bypass valve is controlled to open to 49%-52% opening; Among them, the first set pressure value is 1.05 times the set pressure value of the blast furnace, the second set pressure value is 1.07 times the set pressure value of the blast furnace, the third set pressure value is 1.08 times the set pressure value of the blast furnace, the fourth set pressure value is 1.1 times the set pressure value of the blast furnace, the fifth set pressure value is 1.11 times the set pressure value of the blast furnace, and the sixth set pressure value is 1.13 times the set pressure value of the blast furnace.

5. The control method according to claim 4, characterized in that: Also includes: When it is detected that the blast furnace top pressure is greater than or equal to the first set pressure value during the process of blast furnace top pressure decreasing, the first bypass valve and / or the second bypass valve are controlled to be reduced to a third preset opening, and the opening of the stationary blades of the TRT is adjusted according to the blast furnace top pressure.

6. The control method according to claim 5, characterized in that: If the blast furnace top pressure is greater than or equal to the fifth set pressure value and less than or equal to the sixth set pressure value, the first bypass valve is controlled to be closed to 46%-43% opening; If the blast furnace top pressure is greater than or equal to the third set pressure value and less than or equal to the fourth set pressure value, the first bypass valve and the second bypass valve are controlled to be closed to an opening of 36%-33%; If the blast furnace top pressure is greater than or equal to the first set pressure value and less than or equal to the second set pressure value, the first bypass valve and the second bypass valve are controlled to be closed to 0 opening.

7. The control method according to claim 5, characterized in that: When it is detected that the blast furnace top pressure is greater than or equal to the first set pressure value during the process of blast furnace top pressure decreasing, if the first bypass valve fails, the second bypass valve is controlled to be reduced to a fourth preset opening, and the opening of the stationary blades of the TRT is adjusted according to the blast furnace top pressure, wherein, under the same furnace top pressure, the fourth preset opening is smaller than the third preset opening.

8. The control method according to claim 7, characterized in that: If the blast furnace top pressure is greater than or equal to the fifth set pressure value and less than or equal to the sixth set pressure value, the second bypass valve is controlled to be closed to an opening of 34%-37%; If the blast furnace top pressure is greater than or equal to the third set pressure value and less than or equal to the fourth set pressure value, the second bypass valve is controlled to be closed to an opening of 24%-27%; If the blast furnace top pressure is greater than or equal to the first set pressure value and less than or equal to the second set pressure value, the second bypass valve is controlled to close to 0 opening.

9. The control method according to claim 3, characterized in that: The first bypass valve is a double-acting valve, and the second bypass valve is a single-acting valve.

10. A control system for blast furnace top pressure, characterized in that: include: TRT, a first bypass valve and a controller; the TRT and the first bypass valve are both connected to the blast furnace gas network, the first end of the first bypass valve is connected to the first end of the TRT through a gas pipe, and the second end of the first bypass valve is connected to the second end of the TRT through a gas pipe; The controller is used to detect that when the blast furnace top pressure is greater than or equal to the first set pressure during the rising process of the blast furnace top pressure, it controls the first bypass valve connected to the blast furnace gas residual pressure turbine power generation device TRT to open to a first preset opening, and then adjusts the opening of the stator blades of the TRT according to the blast furnace top pressure.

Images