Flue gas self-adjusting system of blast furnace coal injection mill

Abstract

The utility model discloses a flue gas self-adjusting system of a blast furnace coal injection mill, which comprises a flue gas furnace, a mill and a chimney which are sequentially communicated through a pipeline, and a hot air stop valve, a temperature sensor, an inlet pressure sensor and an outlet pressure sensor are arranged on the pipeline. A first end of an adjusting pipeline is communicated with the pipeline between the hot air cut-off valve and the temperature sensor, a second end of the adjusting pipeline is communicated with the chimney, and an adjusting valve is installed on the adjusting pipeline. According to the flue gas self-adjusting system of the blast furnace coal injection mill, due to the arrangement of the adjusting pipeline, the flue gas amount in the mill can be adjusted, the safety and the stability of powder milling of the mill are greatly improved, an additional channel is provided for flue gas exhaust of the mill, and the flue gas self-adjusting system of the blast furnace coal injection mill is convenient to use. Smoke of the mill can be exhausted through the pipeline for communicating the mill with the chimney and the adjusting pipeline, the smoke exhaust speed is higher, and maintenance of the mill is more facilitated.

Description

Technical Field

[0001] The utility model relates to the technical field of iron-making high-speed coal injection mills, in particular to a flue gas self-regulation system for a blast furnace coal injection mill. Background Art

[0002] The coal injection pulverizing system of an iron-making blast furnace centers around a mill. When the mill pulverizes coal, high-temperature flue gas is introduced. While using the high-temperature flue gas to mix with the raw coal in the mill to make pulverized coal, the high-temperature flue gas also serves as the conveying gas for the pulverized coal. During the operation of the mill, whether it is the raw coal, the introduced high-temperature flue gas, or the pulverized coal after grinding, they are all in a flowing and fluctuating dynamic state. In this fluctuating dynamic state, there is often a situation where pulverized coal accumulates in the mill or its primary air pipe. When pulverized coal accumulates in the mill or the primary air pipe, it is easy to cause the air flow resistance in the mill to increase, the grinding resistance and the flue gas temperature in the pipes before and after the grinding resistance to rise. After the flue gas temperature rises and expands, the mill air pressure will further increase, the slag discharge port of the mill will be blocked, the load of the mill motor will increase, and the power consumption will increase. At the same time, the too high temperature will also cause the pulverized coal in the mill to catch fire and even has the risk of explosion. Content of the Utility Model

[0003] The purpose of the utility model is to provide a flue gas self-regulation system for a blast furnace coal injection mill.

[0004] The technical solution for achieving the purpose of the utility model is: a flue gas self-regulation system for a blast furnace coal injection mill, which includes a flue gas furnace, a mill, and a chimney that are sequentially connected through pipelines. A hot air cut-off valve, a temperature sensor, an inlet pressure sensor, and an outlet pressure sensor are provided on the pipeline. Among them, the hot air cut-off valve, the temperature sensor, and the inlet pressure sensor are all located between the flue gas furnace and the mill and are sequentially distributed along the direction from the flue gas furnace to the mill. The outlet pressure sensor is located between the mill and the chimney. One end of an adjustment pipeline is connected to the pipeline between the hot air cut-off valve and the temperature sensor, and the other end of the adjustment pipeline is connected to the chimney. A regulating valve is installed on the adjustment pipeline. The hot air cut-off valve, the temperature sensor, the inlet pressure sensor, the outlet pressure sensor, and the regulating valve are all electrically connected to a control unit respectively, and the control unit is also electrically connected to an alarm unit.

[0005] Further, the regulating valve is a manual and automatic integrated valve. The regulating valve of the manual and automatic integrated valve can be controlled and adjusted by the control unit or manually adjusted by a human. In particular, in case of an abnormality, it is convenient for manual intervention and adjustment.

[0006] Further, a vent pipe with one end open is connected to the pipeline between the flue gas furnace and the hot air cut-off valve, and a vent valve is installed on the vent pipe. When the air pressure in the flue gas furnace is too high and there is an explosion risk, the vent valve can be opened, and the flue gas can be quickly discharged through the vent pipe to relieve the high-pressure danger in the flue gas furnace.

[0007] Further, a furnace internal pressure sensor is installed in the flue gas furnace, and both the furnace internal pressure sensor and the vent valve are electrically connected to the control unit respectively. The furnace internal pressure sensor senses the air pressure in the flue gas furnace in real time and feeds it back to the control unit. The control unit controls the vent valve according to the air pressure sensed by the furnace internal pressure sensor. If the air pressure sensed by the furnace internal pressure sensor is too high and greater than the set value, the control unit controls the vent valve to open, so that the flue gas in the flue gas furnace can be quickly discharged. In this way, the safety of the operation of the flue gas furnace is greatly guaranteed.

[0008] Further, the vent valve is a manual and automatic integrated valve. The vent valve of the manual and automatic integrated valve can be controlled and adjusted by the control unit, or manually adjusted by humans. Especially in case of abnormality, it is convenient for manual intervention and adjustment.

[0009] Further, the control unit is an MCU controller or a PLC controller.

[0010] Further, the alarm unit is an alarm bell or an alarm light.

[0011] The self-regulating system for the flue gas of the coal pulverizer in the blast furnace of the present utility model. The setting of the regulating pipeline with its first end communicating with the pipeline between the hot air cut-off valve and the temperature sensor and its second end communicating with the chimney. On the one hand, while the flue gas furnace is connected to the pulverizer to supply flue gas to the pulverizer, the flue gas furnace is also connected to the chimney. That is to say, in addition to the discharge path into the pulverizer, the flue gas discharged from the flue gas furnace also has an additional discharge path through the regulating pipeline. The amount of flue gas discharged from the flue gas furnace is either the amount of flue gas discharged into the pulverizer or discharged through the regulating pipeline. When changing the amount of flue gas in the regulating pipeline, the amount of flue gas discharged into the pulverizer can be changed. The addition of the regulating pipeline provides the condition for the adjustability of the amount of flue gas discharged from the flue gas furnace into the pulverizer. In the case of adding the regulating pipeline, combined with the installation of the regulating valve on the regulating pipeline, the setting of the temperature sensor and the inlet pressure sensor at the inlet of the pulverizer, and the setting of the outlet pressure sensor at the outlet of the pulverizer, the temperature sensor senses the temperature of the flue gas at the inlet of the pulverizer, the inlet pressure sensor senses the air pressure at the inlet of the pulverizer, and the outlet pressure sensor senses the air pressure at the outlet of the pulverizer. After judging the temperature and air pressure state in the pulverizer based on the temperature of the flue gas at the inlet of the pulverizer and the pressure difference between the inlet air pressure and the outlet air pressure of the pulverizer, by making corresponding adjustments to the regulating valve, the amount of flue gas in the regulating pipeline is changed, and then the amount of flue gas discharged into the pulverizer is adjusted, regulating the air pressure and temperature in the pulverizer, so that although the air pressure and temperature in the pulverizer fluctuate, each time the fluctuation exceeds the range, it can be automatically adjusted back to the normal production state. In this way, the safety and stability of the pulverizing and powder-making of the pulverizer are greatly improved, avoiding the risk of the increase in the flue gas temperature and air pressure in the pulverizer and causing the ignition or even explosion of the pulverized coal when there is a situation such as the accumulation of pulverized coal. The pulverized coal in the pulverizer is safer, the equipment runs more stably, and the energy consumption cost is also lower.

[0012] On the other hand, in addition to the pipeline connecting the pulverizer and the chimney, the regulating pipeline also provides another channel for the exhaust gas of the pulverizer. For example, after the pulverizer stops running and is under maintenance, the hot air cut-off valve can be closed so that there is no more incoming flue gas in the pulverizer, and then the regulating valve is opened. The flue gas of the pulverizer can be discharged not only through the pipeline connecting the pulverizer and the chimney, but also through the regulating pipeline. Compared with a single pipeline, the double-pipeline exhaust speed is faster after adding the regulating pipeline, which is more conducive to the maintenance of the pulverizer and improves the maintenance efficiency of the pulverizer.

[0013] The self - regulating system for the flue gas of the coal - injection mill in the blast furnace of the present utility model adjusts the regulating valve, and when adjusting the amount of flue gas introduced into the mill, it is based on the temperature of the flue gas at the mill inlet and the pressure difference between the inlet pressure and the outlet pressure of the mill. The dual - condition judgment of temperature and pressure, compared with the single - condition judgment of temperature or pressure, not only has more comprehensive judgment elements and more accurate judgment, but also can monitor the states of the signal lines of the temperature sensor, the inlet pressure sensor, and the outlet pressure sensor with each other according to the detection results of temperature and pressure, and judge whether the temperature sensor, the inlet pressure sensor, or the outlet pressure sensor is damaged, which is convenient for the maintenance of the temperature sensor, the inlet pressure sensor, and the outlet pressure sensor, etc.

[0014] In the self - regulating system for the flue gas of the coal - injection mill in the blast furnace of the present utility model, the temperature sensor is set at the mill inlet to detect the temperature of the flue gas in the mill, and the inlet pressure sensor and the outlet pressure sensor are set on the pipelines at the mill inlet and outlet. The air pressure in the mill is determined by the pressure difference between the inlet pressure and the outlet pressure of the mill. Compared with setting the temperature sensor and the pressure sensor in the mill, the operation of setting the temperature sensor, the inlet pressure sensor, and the outlet pressure sensor on the pipeline is more convenient.

[0015] In addition, in the self - regulating system for the flue gas of the coal - injection mill in the blast furnace of the present utility model, when adjusting the amount of flue gas introduced into the mill, the combination of the temperature sensor, the inlet pressure sensor, the outlet pressure sensor, and the control unit can realize full - automatic real - time adjustment, and its timeliness and convenience of adjustment are better. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a schematic structural diagram of the self - regulating system for the flue gas of the coal - injection mill in the blast furnace of the present utility model;

[0017] Figure 2 is a module control diagram of the self - regulating system for the flue gas of the coal - injection mill in the blast furnace of the present utility model. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0018] The following describes in detail the preferred embodiments of the self - regulating system for the flue gas of the coal - injection mill in the blast furnace of the present utility model with reference to the drawings:

[0019] As Figure 1 and Figure 2As shown in the figure, a self-regulating system for the flue gas of a pulverized coal injection mill in a blast furnace includes a flue gas furnace 1, a mill 2, and a chimney 3 that are sequentially connected through a pipeline 10. A hot air cut-off valve 4, a temperature sensor 5, an inlet pressure sensor 61, and an outlet pressure sensor 62 are provided on the pipeline 10. Among them, the hot air cut-off valve 4, the temperature sensor 5, and the inlet pressure sensor 61 are all located between the flue gas furnace 1 and the mill 2 and are sequentially distributed along the direction from the flue gas furnace 1 to the mill 2. The outlet pressure sensor 62 is located between the mill 2 and the chimney 3. One end 71 of an adjustment pipeline 7 is connected to the pipeline 10 between the hot air cut-off valve 4 and the temperature sensor 5, and the other end 72 of the adjustment pipeline 7 is connected to the chimney 3. A regulating valve 8 is installed on the adjustment pipeline 7. The hot air cut-off valve 4, the temperature sensor 5, the inlet pressure sensor 61, the outlet pressure sensor 62, and the regulating valve 8 are all electrically connected to a control unit 9, and the control unit 9 is also electrically connected to an alarm unit 14.

[0020] For the self-regulating system of the flue gas of the pulverized coal injection mill in the blast furnace of the present utility model, the flue gas furnace 1 serves as an exhaust gas collection furnace for the hot blast stove and is used to provide flue gas for the mill 2; the mill 2 is used for pulverizing coal; the chimney 3 is used for exhausting the flue gas of the mill 2. On the pipeline 10, the hot air cut-off valve 4 is used to control the on-off of the pipeline 10; the temperature sensor 5 is used to sense the temperature of the flue gas at the inlet of the mill 2; the inlet pressure sensor 61 is used to sense the air pressure at the inlet of the mill 2; the outlet pressure sensor 62 is used to sense the air pressure at the outlet of the mill 2. The regulating valve 8 is used to control the on-off and flow rate of the adjustment pipeline 7.

[0021] In the self-regulating system of the flue gas of the pulverized coal injection mill in the blast furnace of the present utility model, during operation, the hot air cut-off valve 4 is opened, and the flue gas furnace 1 passes the flue gas into the mill 2 through the pipeline 10. The flue gas entering the mill 2 is mixed with the raw coal in the mill 2 to be ground into pulverized coal, and then the waste gas in the mill 2 is discharged into the chimney 3 through the pipeline 10 and discharged by the chimney 3.

[0022] In the self-regulating system of the flue gas of the pulverized coal injection mill in the blast furnace of the present utility model, during the above working process, the temperature sensor 5 continuously senses the temperature of the flue gas at the inlet of the mill 2, the inlet pressure sensor 61 continuously senses the air pressure at the inlet of the mill 2, and the outlet pressure sensor 62 continuously senses the air pressure at the outlet of the mill 2. Based on the temperature of the flue gas at the inlet of the mill 2 and the pressure difference between the air pressure at the inlet and the outlet of the mill 2, the control unit 9 judges the temperature and air pressure state in the mill 2 and adjusts the regulating valve 8 or controls the alarm unit 14 to issue an alarm.

[0023] If the temperature of the flue gas at the inlet of the mill 2 is too high, higher than the set value, and at the same time, the pressure difference between the inlet pressure and the outlet pressure of the mill 2 also exceeds the normal pressure difference range, at this time, it is determined that the air pressure in the mill 2 is higher than the normal range. The control unit 9 controls the regulating valve 8 to open. After the regulating valve 8 opens, a part of the flue gas discharged from the flue gas furnace 1 enters the mill 2, and the other part is discharged through the regulating pipeline 7, reducing the flue gas temperature in the mill 2 and lowering the air pressure. When the temperature of the flue gas at the inlet of the mill 2, the pressure difference between the inlet pressure and the outlet pressure of the mill 2 both return to normal, the control unit 9 controls the regulating valve 8 to close.

[0024] If the temperature of the flue gas at the inlet of the mill 2 is too high, but the pressure difference between the inlet pressure and the outlet pressure of the mill 2 is within the normal pressure difference range, or the temperature of the flue gas at the inlet of the mill 2 is within the normal range, while the pressure difference between the inlet pressure and the outlet pressure of the mill 2 exceeds the normal pressure difference range, at this time, the control unit 9 determines that the temperature sensor 5, the inlet pressure sensor 61 or the outlet pressure sensor 62 is abnormal. At this time, the control unit 9 controls the alarm unit 14 to issue an alarm to notify the staff to perform inspections and confirmations. Once it is confirmed that the temperature sensor 5, the inlet pressure sensor 61 or the outlet pressure sensor 62 is damaged, there is a signal transmission error, or there is a false alarm, the damaged temperature sensor 5, inlet pressure sensor 61 or outlet pressure sensor 62 can be replaced.

[0025] The self-adjusting system for the flue gas of the coal pulverizer in the blast furnace of the utility model. The setting of the regulating pipeline 7 with its first end 71 communicating with the pipeline 10 between the hot air cut-off valve 4 and the temperature sensor 5 and its second end 72 communicating with the chimney 3. On the one hand, on the basis that the flue gas furnace 1 is connected to the pulverizer 2 to supply flue gas to the pulverizer 2, the flue gas furnace 1 is also connected to the chimney 3. That is to say, in addition to the discharge path of the flue gas discharged from the flue gas furnace 1 into the pulverizer 2, there is also an additional discharge path through the regulating pipeline 7. The amount of flue gas discharged from the flue gas furnace 1 is either the amount of flue gas discharged into the pulverizer 2 or discharged through the regulating pipeline 7. When changing the amount of flue gas on the regulating pipeline 7, the amount of flue gas discharged into the pulverizer 2 can be changed. The addition of the regulating pipeline 7 provides the condition for adjusting the amount of flue gas discharged from the flue gas furnace 1 into the pulverizer 2. In the case of adding the regulating pipeline 7, combined with the installation of the regulating valve 8 on the regulating pipeline 7, the setting of the temperature sensor 5 and the inlet pressure sensor 61 at the inlet of the pulverizer 2, and the setting of the outlet pressure sensor 62 at the outlet of the pulverizer 2, the temperature sensor 5 senses the temperature of the flue gas at the inlet of the pulverizer 2, the inlet pressure sensor 61 senses the air pressure at the inlet of the pulverizer 2, and the outlet pressure sensor 62 senses the air pressure at the outlet of the pulverizer 2. After judging the temperature and air pressure state in the pulverizer 2 based on the temperature of the flue gas at the inlet of the pulverizer 2 and the pressure difference between the inlet air pressure and the outlet air pressure of the pulverizer 2, by making corresponding adjustments to the regulating valve 8, the amount of flue gas on the regulating pipeline 7 is changed, and then the amount of flue gas discharged into the pulverizer 2 is adjusted, regulating the air pressure and temperature in the pulverizer 2, so that although the air pressure and temperature in the pulverizer 2 fluctuate, each time the fluctuation exceeds the range, it can be automatically adjusted back to the normal production state. In this way, the safety and stability of the pulverizer 2 for grinding and making powder are greatly improved. When avoiding situations such as coal powder accumulation, the temperature and air pressure of the flue gas in the pulverizer 2 increase, and the risk of coal powder ignition or even explosion is caused. The coal powder in the pulverizer 2 is safer, the equipment runs more stably, and the energy consumption cost is also lower.

[0026] On the other hand, in addition to the pipeline 10 connecting the pulverizer 2 and the chimney 3, the regulating pipeline 7 also provides another channel for the exhaust of the pulverizer 2. For example, after the pulverizer 2 stops and is under maintenance, the hot air cut-off valve 4 can be closed so that there is no more incoming flue gas in the pulverizer 2, and then the regulating valve 8 is opened. The flue gas of the pulverizer 2 can be discharged not only through the pipeline 10 connecting the pulverizer 2 and the chimney 3, but also through the regulating pipeline 7. Compared with a single pipeline, the double-pipeline exhaust speed is faster after adding the regulating pipeline 7, which is more conducive to the maintenance of the pulverizer 2 and improves the maintenance efficiency of the pulverizer 2.

[0027] The utility model provides a blast furnace coal injection mill flue gas self-regulating system, which adjusts the regulating valve 8 and further adjusts the flue gas volume introduced into the mill 2 based on the temperature of the inlet flue gas of the mill 2 and the pressure difference between the inlet air pressure and the outlet air pressure of the mill 2. The dual condition judgment of temperature and pressure is not only more comprehensive and accurate than the single condition judgment of temperature or pressure, but also can monitor the states of the signal lines of the temperature sensor 5, the inlet pressure sensor 61 and the outlet pressure sensor 62 based on the detection results of temperature and pressure, and judge whether the temperature sensor 5, the inlet pressure sensor 61 or the outlet pressure sensor 62 is damaged, so as to facilitate the maintenance of the temperature sensor 5, the inlet pressure sensor 61 and the outlet pressure sensor 62.

[0028] In the utility model, the flue gas self-regulating system of the blast furnace coal injection mill is provided with the temperature sensor 5 at the inlet of the mill 2 to detect the temperature of the flue gas in the mill 2, and the inlet pressure sensor 61 and the outlet pressure sensor 62 are provided on the pipes 10 at the inlet and outlet of the mill 2. The air pressure in the mill 2 is determined by the pressure difference between the inlet air pressure and the outlet air pressure of the mill 2. Compared with providing the temperature sensor and the pressure sensor in the mill 2, the operation of providing the temperature sensor 5, the inlet pressure sensor 61 and the outlet pressure sensor 62 on the pipe 10 is more convenient.

[0029] In addition, the utility model of the blast furnace coal injection mill flue gas self-regulating system, when adjusting the amount of flue gas introduced into the mill 2, the combination of the temperature sensor 5, the inlet pressure sensor 61, the outlet pressure sensor 62 and the control unit 9 can realize fully automatic real-time adjustment, and the timeliness and convenience of the adjustment are better.

[0030] In the utility model of the blast furnace coal injection mill flue gas self-regulating system, preferably, the regulating valve 8 is a manual and automatic integrated valve. The regulating valve 8 of the manual and automatic integrated valve can be controlled and adjusted by the control unit 9, and can also be manually adjusted. In particular, under abnormal circumstances, manual intervention can be convenient for adjustment.

[0031] In the utility model, the flue gas self-regulating system of the coal injection mill of the blast furnace is preferably connected to the pipe 10 between the flue gas furnace 1 and the hot air shut-off valve 4, which has an open end and a venting pipe 11, and a venting valve 12 is installed on the venting pipe 11. When the air pressure in the flue gas furnace 1 is too high and there is a risk of explosion, the venting valve 12 can be opened to quickly exhaust the smoke through the venting pipe 11, thereby eliminating the high pressure danger in the flue gas furnace 1.

[0032] The flue gas self - regulating system of the blast furnace pulverized coal injection mill of the present utility model. Preferably, a furnace internal pressure sensor 13 is installed in the flue gas furnace 1, and both the furnace internal pressure sensor 13 and the relief valve 12 are electrically connected to the control unit 9 respectively. The furnace internal pressure sensor 13 senses the air pressure in the flue gas furnace 1 in real - time and feeds it back to the control unit 9. The control unit 9 controls the relief valve 12 according to the air pressure sensed by the furnace internal pressure sensor 13. For example, when the air pressure sensed by the furnace internal pressure sensor 13 is too high and greater than the set value, the control unit 9 controls the relief valve 12 to open, so that the flue gas in the flue gas furnace 1 can be quickly discharged. In this way, the safety of the operation of the flue gas furnace 1 is greatly guaranteed.

[0033] The flue gas self - regulating system of the blast furnace pulverized coal injection mill of the present utility model. Preferably, the relief valve 12 is a valve that combines manual and automatic functions. The relief valve 12 with the combined manual and automatic function can be controlled and adjusted by the control unit 9, or can be manually adjusted by humans. Especially, in case of an abnormality, it is convenient for manual intervention and adjustment.

[0034] The flue gas self - regulating system of the blast furnace pulverized coal injection mill of the present utility model, the control unit 9 is an MCU controller or a PLC controller.

[0035] The flue gas self - regulating system of the blast furnace pulverized coal injection mill of the present utility model, the alarm unit 14 is an alarm bell or an alarm light.

[0036] For the flue gas self - regulating system of the blast furnace pulverized coal injection mill of the present utility model, the hot air cut - off valve 4, the temperature sensor 5, the inlet pressure sensor 61, the outlet pressure sensor 62, the regulating valve 8, the control unit 9, the alarm unit 14, etc. are all of existing structures, and the present utility model will not elaborate on them too much.

[0037] For those of ordinary skill in the technical field to which the present utility model pertains, without departing from the concept of the present utility model, several simple deductions or substitutions can still be made, and all should be regarded as belonging to the protection scope of the present utility model.

Claims

1. A blast furnace coal injection mill flue gas self-regulating system, comprising a flue gas furnace, a mill and a chimney connected in sequence through a pipeline, characterized in that: The pipeline is provided with a hot air shut-off valve, a temperature sensor, an inlet pressure sensor and an outlet pressure sensor, wherein the hot air shut-off valve, the temperature sensor and the inlet pressure sensor are all located between the flue gas furnace and the mill, and are distributed in sequence along the direction from the flue gas furnace to the mill, the outlet pressure sensor is located between the mill and the chimney, a first end of a regulating pipeline is connected to the pipeline between the hot air shut-off valve and the temperature sensor, and a second end of the regulating pipeline is connected to the chimney, a regulating valve is installed on the regulating pipeline, the hot air shut-off valve, the temperature sensor, the inlet pressure sensor, the outlet pressure sensor and the regulating valve are each electrically connected to a control unit, and the control unit is also electrically connected to an alarm unit.

2. The blast furnace coal injection mill flue gas self-regulating system according to claim 1 is characterized in that: The regulating valve is a manual and automatic integrated valve.

3. The blast furnace coal injection mill flue gas self-regulating system according to claim 1 is characterized in that: The pipeline between the flue gas furnace and the hot air shut-off valve is connected to a vent pipe with an open end, and a vent valve is installed on the vent pipe.

4. The blast furnace coal injection mill flue gas self-regulating system according to claim 3 is characterized in that: A furnace pressure sensor is installed in the flue gas furnace, and the furnace pressure sensor and the relief valve are electrically connected to the control unit respectively.

5. The blast furnace coal injection mill flue gas self-regulating system according to claim 3 is characterized by: The relief valve is a manual and automatic integrated valve.

6. The blast furnace coal injection mill flue gas self-regulating system according to claim 1, characterized in that: The control unit is an MCU controller or a PLC controller.

7. The blast furnace coal injection mill flue gas self-regulating system according to claim 1 is characterized in that: The alarm unit is an alarm bell or an alarm light.

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