Method and system for monitoring water fetching effect in blowing-out process of blast furnace empty stockline

Abstract

The invention provides a method and system for monitoring the water fetching effect in the blowing-out process of an empty stockline of a blast furnace, and the method comprises the steps: obtaining the top temperature data of the top of the blast furnace at each point position; calculating a mean value of the top temperature data of each point location; obtaining a top temperature difference value according to the maximum value and the minimum value of the top temperature data of each point location; respectively constructing a top temperature mean value monitoring chart and a top temperature difference monitoring chart by taking the mean value and the top temperature difference value of the top temperature data of each point location as a y axis and taking a time sequence as an x axis; and completing the cooling of the blast furnace top temperature based on the top temperature mean value monitoring chart and the top temperature difference value monitoring chart. According to the method, the air supply quantity and the water spraying quantity of the atomizing water gun are adjusted according to the top temperature mean value and the difference value between the top temperature highest point and the top temperature lowest point, the water spraying quantity in the whole furnace shutdown process can be fully vaporized before the water falls into the material face, the knocking phenomenon is greatly reduced, and the furnace shutdown maintenance safety is improved.

Description

Technical Field

[0001] The invention relates to the technical field of blast furnace metallurgy, and in particular to a monitoring method and system for water pumping effect during the shutdown process of an empty material line of a blast furnace. Background Art

[0002] During the operation of the blast furnace, the cooling wall or the hearth refractory will be damaged by the wear of materials, erosion of slag iron and thermal shock. When the cooling wall or the hearth refractory is damaged to a certain extent, the blast furnace needs to be shut down for overhaul. During the shutdown process, the loading from the top should be stopped, and the materials in the original blast furnace should be continuously consumed by the hot air blown in. The molten iron and slag generated after the materials are consumed are gathered in the hearth and discharged regularly. After the materials in the blast furnace are continuously consumed, the inner wall of the blast furnace is exposed for easy maintenance. However, during the shutdown process, as the materials gradually decrease, a large amount of high-temperature coal gas generated by the reaction of the lower hot air and coke causes the furnace top temperature to rise due to the small amount of materials for heat exchange. Excessive furnace top temperature will burn the furnace top equipment and cause accidents. Therefore, it is necessary to take water pumping from the furnace top to reduce the gas temperature. In the later stage, when the gas temperature is too high and the cooling capacity of the cooling water is insufficient, it is necessary to cooperate with the method of gradually reducing the air volume to avoid excessive furnace top temperature. However, a large amount of water injection will cause some water to fail to vaporize in time and fall on the material surface. After reacting with the hot material, the volume will expand rapidly and produce a "detonation" phenomenon, which is harmful to safety. Continuously reducing the air volume too much can reduce the furnace top temperature, but it will cause the material lowering line to travel too long, which will also cause the water to fail to vaporize in time, endangering safety. It is of great significance to determine the amount of water injection to vaporize in time through accurate monitoring, maintain a large air volume for a long time, and realize fast and safe shutdown maintenance. Summary of the invention

[0003] In order to solve the above problems, the purpose of the present invention is to provide a method and system for monitoring the water injection effect during the shutdown process of the blast furnace empty material line.

[0004] To achieve the above object, the present invention provides the following solutions:

[0005] A method for monitoring the water injection effect during the shutdown of a blast furnace empty material line, comprising:

[0006] Obtain the top temperature data of the blast furnace top at various points;

[0007] Calculate the mean of top temperature data at each point;

[0008] The top temperature difference is obtained based on the maximum and minimum values ​​of the top temperature data at each point;

[0009] With the mean and top temperature difference of each point's top temperature data as the y-axis, and the time sequence as the x-axis, build a top temperature mean monitoring chart and a top temperature difference monitoring chart respectively;

[0010] The blast furnace top temperature is cooled down based on the top temperature average monitoring chart and the top temperature difference monitoring chart.

[0011] Preferably, the blast furnace maintenance is completed based on the top temperature mean monitoring chart and the top temperature difference monitoring chart, including:

[0012] When the mean value of the top temperature data is in the range of 100-350°C and the top temperature difference is less than 100°C, the working parameters of the atomizing water gun on the top of the blast furnace are kept unchanged, and the air volume blown into the blast furnace is kept unchanged;

[0013] When the average value of the top temperature data is in the range of 100-350℃ and the top temperature difference is greater than 100℃, the water supply pressure of the atomizing water gun on the top of the blast furnace is increased to improve the atomization effect;

[0014] When the mean of the top temperature data is greater than or equal to 350°C, and the top temperature difference is greater than 100°C, the water spraying amount of the atomizing water gun on the top of the blast furnace is increased. If the water spraying amount has reached the maximum, the air volume blown into the blast furnace is reduced.

[0015] Preferably, when the mean value of the top temperature data is greater than or equal to 350°C and the top temperature difference is less than 100°C, the water spraying amount of the atomizing water gun at the top of the blast furnace is increased, and if the water spraying amount has reached the maximum, the air volume blown into the blast furnace is reduced;

[0016] When the average value of the top temperature data is less than 100°C, the water spray volume of the atomizing water gun on the top of the blast furnace is reduced, and the air volume blown into the blast furnace is increased.

[0017] The present invention also provides a monitoring system for the water pumping effect during the shutdown process of the blast furnace empty material line, comprising:

[0018] The temperature sensor is connected to the microprocessor through the RS485 communication circuit, and is used to collect the top temperature data of the blast furnace top at various points, and transmit the top temperature data to the microprocessor;

[0019] The alarm module is connected to the microprocessor. When any top temperature data exceeds a preset value, the microprocessor controls the alarm module to sound an alarm.

[0020] Preferably, the alarm module comprises:

[0021] A first resistor, one end of which is connected to an IO port of a microprocessor;

[0022] A transistor, wherein the base of the transistor is connected to the other end of the first resistor, and the emitter of the transistor is grounded;

[0023] A second resistor, one end of the second resistor is connected to the base of the transistor, and the other end of the second resistor is grounded;

[0024] A voltage stabilizing diode, wherein the anode of the voltage stabilizing diode is connected to the collector of the transistor, the cathode of the voltage stabilizing diode is connected to one end of the speaker, and the other end of the speaker is connected to the collector of the transistor.

[0025] According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0026] The present invention provides a method and system for monitoring the water pumping effect during the shutdown process of an empty material line of a blast furnace. Compared with the prior art, the present invention adjusts the air supply volume and the water spraying volume of an atomizing water gun according to the top temperature average and the difference between the highest point and the lowest point of the top temperature, so that the water pumped in the entire shutdown process can be fully vaporized before it falls in front of the materials, thereby greatly reducing the occurrence of the "explosion" phenomenon and improving the safety of shutdown maintenance. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0028] Figure 1 A schematic diagram of a monitoring chart provided by the present invention;

[0029] Figure 2 A schematic diagram of a monitoring system for water pumping effect during the shutdown process of a blast furnace empty material line provided by the present invention;

[0030] Figure 3 A schematic diagram of the temperature sensor collection position provided by the present invention;

[0031] Figure 4 A circuit diagram of an alarm module provided by the present invention;

[0032] Figure 5 This is a circuit diagram of the power module provided by the present invention. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0035] To achieve the above object, the technical solution adopted by the present invention is:

[0036] See also Figure 1 , a method for monitoring the water injection effect during the shutdown process of a blast furnace empty material line, comprising:

[0037] Step 1: Obtain the top temperature data of the blast furnace top at various points;

[0038] Step 2: Calculate the mean of the top temperature data at each point;

[0039] Step 3: Obtain the top temperature difference according to the maximum and minimum values ​​of the top temperature data at each point;

[0040] Step 4: Use the mean and top temperature difference of each point top temperature data as the y-axis and the time sequence as the x-axis to construct a top temperature mean monitoring chart and a top temperature difference monitoring chart respectively;

[0041] Step 5: Complete cooling of the blast furnace top temperature based on the top temperature average monitoring chart and the top temperature difference monitoring chart.

[0042] Further, step 5 includes:

[0043] When the mean value of the top temperature data is in the range of 100-350°C and the top temperature difference is less than 100°C, the working parameters of the atomizing water gun on the top of the blast furnace are kept unchanged, and the air volume blown into the blast furnace is kept unchanged;

[0044] When the average value of the top temperature data is in the range of 100-350℃ and the top temperature difference is greater than 100℃, the water supply pressure of the atomizing water gun on the top of the blast furnace is increased to improve the atomization effect;

[0045] When the mean of the top temperature data is greater than or equal to 350°C, and the top temperature difference is greater than 100°C, the water spraying amount of the atomizing water gun on the top of the blast furnace is increased. If the water spraying amount has reached the maximum, the air volume blown into the blast furnace is reduced.

[0046] When the mean value of the top temperature data is greater than or equal to 350°C, and the top temperature difference is less than 100°C, the water spraying amount of the atomizing water gun on the top of the blast furnace is increased. If the water spraying amount has reached the maximum, the air volume blown into the blast furnace is reduced.

[0047] When the average value of the top temperature data is less than 100°C, the water spray volume of the atomizing water gun on the top of the blast furnace is reduced, and the air volume blown into the blast furnace is increased.

[0048] The monitoring method of the present invention is further described below in conjunction with specific embodiments:

[0049] 1. During the material lowering process, the monitoring system is used to continuously collect the blast furnace top temperature data and process the top temperature data; first, the top temperature average Xbar is calculated, Xbar = (top temperature 1 + top temperature 2 + top temperature 3 + top temperature 4) / 4; then the top temperature difference R is calculated, R = top temperature Max - top temperature Min (top temperature Max is the largest of a group of 4 top temperature data collected at the same time, and top temperature Min is the smallest of a group of 4 top temperature data collected at the same time.)

[0050] 2. Use the data collected in the previous step to draw a monitoring chart: First, the monitoring chart is divided into two parts, the upper part monitors the top temperature average Xbar, and the lower part monitors the top temperature difference R. The corresponding points above and below are data collected at the same time. The calculated Xbar and R values ​​are drawn in chronological order.

[0051] 3. The range of the mean value in the monitoring table is set to 0-400℃, and the range of the difference value is set to 0-300℃. After the top temperature data of the acquisition point is calculated, it is drawn in the monitoring table.

[0052] 4. When Xbar is in the range of 100-350℃ and R value is less than 100℃, the atomization effect is good. The air volume can be maintained under the premise that the gas composition is satisfied. If R value is greater than 100℃, the atomization effect of the water gun in the circumferential direction needs to be checked. The water supply pressure can be increased for the water gun with poor effect to enhance the atomization effect. If R value is greater than 100℃ and Xbar is greater than or equal to 350℃, the water volume needs to be increased and the ability of the circumferential water gun needs to be checked for obvious deviations. If the atomization effect has been improved and the water volume is the largest, the water capacity and air volume do not match and the air volume needs to be reduced. If R value is less than 100℃ and Xbar is greater than or equal to 350℃, the atomization is good but the water volume is insufficient and the water volume needs to be increased. If the water volume is already the largest, the gas flow is too large and the air volume needs to be reduced. If Xbar is less than 100℃, the atomization is good but the water volume is too large and the air volume needs to be maintained at a high level to reduce the water volume.

[0053] like Figure 1As shown in the figure, in the characterization stage 1, R value is greater than 100℃, Xbar is less than 350℃. This stage is when a water gun with poor atomization effect is used. Xbar is high and R value is high, which is manifested in that the difference between the top temperature points is large, and the effect of atomized water cooling high-temperature gas is not good. In this stage, the atomization effect needs to be strengthened. After using a water gun with better atomization effect, Xbar and R value both decrease and enter the characterization stage 2; in the characterization stage 2, a water gun with good atomization effect is used. It can be seen that R value is less than 100℃, 100℃<Xbar<350℃. During this period, a large air volume can be maintained to accelerate the process of lowering the material surface; in characterization 3, R value is greater than 100℃, and Xbar has been on an upward trend. In this stage, the atomization effect and water volume are at the best level, indicating that the material surface here is too deep and the cooling capacity is insufficient. The air volume needs to be gradually reduced to ensure Xbar<350℃.

[0054] The present invention monitors the mean and difference of the top temperature when the blast furnace starts to supply air, and then adjusts the air supply volume and the water spraying volume of the atomizing water gun according to the mean of the highest point and the lowest point of the material top temperature and the difference between the highest point and the lowest point, so that the water volume can be fully vaporized before it falls on the material surface during the entire shutdown process, which greatly reduces the occurrence of "detonation" and improves the safety of shutdown maintenance.

[0055] See also Figure 2 The present invention also provides a monitoring system for the water pumping effect during the shutdown process of the blast furnace empty material line, comprising:

[0056] The temperature sensor is connected to the microprocessor through the RS485 communication circuit to collect the top temperature data of the blast furnace top at various points and transmit the top temperature data to the microprocessor; Figure 3 As shown, a plurality of temperature sensors 2 are arranged on the gas riser 1 on the top of the blast furnace, for collecting top temperature data of the blast furnace top at various points.

[0057] The alarm module is connected to the microprocessor. When any top temperature data exceeds a preset value, the microprocessor controls the alarm module to sound an alarm.

[0058] Further, such as Figure 4 As shown, the alarm module includes:

[0059] A first resistor R1, one end of which is connected to an IO port of a microprocessor;

[0060] A transistor Q, wherein the base of the transistor Q is connected to the other end of the first resistor, and the emitter of the transistor Q is grounded;

[0061] A second resistor R2, one end of the second resistor R2 is connected to the base of the transistor Q, and the other end of the second resistor R2 is grounded;

[0062] A voltage regulator diode D, an anode of the voltage regulator diode D is connected to the collector of the transistor, a cathode of the voltage regulator diode D is connected to one end of a speaker P, and the other end of the speaker P is connected to the collector of the transistor Q. When any top temperature data exceeds a preset value, the IO port of the microprocessor sends a high level, so that the speaker P is powered on and makes a sound.

[0063] Figure 5 This is the circuit diagram of the power module of the microprocessor. The function of the voltage regulator D0 in the power module is to raise the drain of the field effect transistor N2 so that it works in the saturation region. According to the working principle of the field effect transistor in the saturation region, the current passing through the microprocessor is a constant value at this time.

[0064] According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0065] Compared with the prior art, the present invention monitors the mean and difference of the top temperature when the blast furnace starts to supply air, and then adjusts the air supply volume and the water spraying volume of the atomizing water gun according to the mean of the highest and lowest points of the material top temperature and the difference between the highest point and the lowest point, so that the water volume can be fully vaporized before it falls on the material surface during the entire shutdown process, which greatly reduces the occurrence of "detonation" and improves the safety of shutdown maintenance.

[0066] This article uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core ideas of the present invention. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A method for monitoring the water pumping effect during the shutdown of a blast furnace empty material line, characterized in that: include: Obtain the top temperature data of the blast furnace top at various points; Calculate the mean of top temperature data at each point; The top temperature difference is obtained based on the maximum and minimum values ​​of the top temperature data at each point; With the mean and top temperature difference of each point's top temperature data as the y-axis, and the time sequence as the x-axis, build a top temperature mean monitoring chart and a top temperature difference monitoring chart respectively; The blast furnace top temperature is cooled down based on the top temperature average monitoring chart and the top temperature difference monitoring chart.

2. The method for monitoring the water pumping effect during the shutdown of a blast furnace empty material line according to claim 1, characterized in that: The blast furnace maintenance is completed based on the top temperature mean monitoring chart and the top temperature difference monitoring chart, including: When the mean value of the top temperature data is in the range of 100-350°C and the top temperature difference is less than 100°C, the working parameters of the atomizing water gun on the top of the blast furnace are kept unchanged, and the air volume blown into the blast furnace is kept unchanged; When the average value of the top temperature data is in the range of 100-350℃ and the top temperature difference is greater than 100℃, the water supply pressure of the atomizing water gun on the top of the blast furnace is increased to improve the atomization effect; When the mean of the top temperature data is greater than or equal to 350°C, and the top temperature difference is greater than 100°C, the water spraying amount of the atomizing water gun on the top of the blast furnace is increased. If the water spraying amount has reached the maximum, the air volume blown into the blast furnace is reduced.

3. The method for monitoring the water pumping effect during the shutdown of a blast furnace empty material line according to claim 2, characterized in that: When the mean value of the top temperature data is greater than or equal to 350°C, and the top temperature difference is less than 100°C, the water spraying amount of the atomizing water gun on the top of the blast furnace is increased. If the water spraying amount has reached the maximum, the air volume blown into the blast furnace is reduced. When the average value of the top temperature data is less than 100°C, the water spray volume of the atomizing water gun on the top of the blast furnace is reduced, and the air volume blown into the blast furnace is increased.

4. A monitoring system for the water pumping effect during the shutdown of a blast furnace empty material line, characterized in that: include: The temperature sensor is connected to the microprocessor through the RS485 communication circuit, and is used to collect the top temperature data of the blast furnace top at various points, and transmit the top temperature data to the microprocessor; The alarm module is connected to the microprocessor. When any top temperature data exceeds a preset value, the microprocessor controls the alarm module to sound an alarm.

5. A monitoring system for the water pumping effect during the shutdown of a blast furnace empty material line as claimed in claim 4, characterized in that: The alarm module comprises: A first resistor, one end of which is connected to an IO port of a microprocessor; A transistor, wherein the base of the transistor is connected to the other end of the first resistor, and the emitter of the transistor is grounded; A second resistor, one end of the second resistor is connected to the base of the transistor, and the other end of the second resistor is grounded; A voltage stabilizing diode, wherein the anode of the voltage stabilizing diode is connected to the collector of the transistor, the cathode of the voltage stabilizing diode is connected to one end of the speaker, and the other end of the speaker is connected to the collector of the transistor.

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