CN117109027A - Automatic ignition and flameout interlocking protection control method for heat accumulating type gas hot blast stove - Google Patents

Automatic ignition and flameout interlocking protection control method for heat accumulating type gas hot blast stove Download PDF

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Publication number
CN117109027A
CN117109027A CN202311088501.5A CN202311088501A CN117109027A CN 117109027 A CN117109027 A CN 117109027A CN 202311088501 A CN202311088501 A CN 202311088501A CN 117109027 A CN117109027 A CN 117109027A
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CN
China
Prior art keywords
burner
gas
hot blast
blast stove
ignition
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202311088501.5A
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Chinese (zh)
Inventor
马运光
王升光
王国增
左成义
王安绪
王帅
刘敦良
李庆勇
牟宏俊
魏中
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Rizhao Steel Holding Group Co Ltd
Original Assignee
Rizhao Steel Holding Group Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Rizhao Steel Holding Group Co Ltd filed Critical Rizhao Steel Holding Group Co Ltd
Priority to CN202311088501.5A priority Critical patent/CN117109027A/en
Publication of CN117109027A publication Critical patent/CN117109027A/en
Pending legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23N—REGULATING OR CONTROLLING COMBUSTION
    • F23N5/00—Systems for controlling combustion
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21B—MANUFACTURE OF IRON OR STEEL
    • C21B9/00—Stoves for heating the blast in blast furnaces
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23N—REGULATING OR CONTROLLING COMBUSTION
    • F23N5/00—Systems for controlling combustion
    • F23N5/24—Preventing development of abnormal or undesired conditions, i.e. safety arrangements
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23N—REGULATING OR CONTROLLING COMBUSTION
    • F23N2227/00—Ignition or checking
    • F23N2227/02—Starting or ignition cycles
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23N—REGULATING OR CONTROLLING COMBUSTION
    • F23N2229/00—Flame sensors
    • F23N2229/20—Camera viewing

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Regulation And Control Of Combustion (AREA)

Abstract

The application discloses an automatic ignition and flameout interlocking protection control method for a heat accumulating type gas hot blast stove, which belongs to the field of automatic control and comprises the following steps: s1, starting a system: self-checking and purging by a Programmable Logic Controller (PLC); s2, igniting a diesel oil burner; s3, igniting the nearest burner; s4, sequentially igniting other burners: s5, closing the diesel oil burner. Compared with the prior art, the method has the characteristics of safety and high efficiency.

Description

Automatic ignition and flameout interlocking protection control method for heat accumulating type gas hot blast stove
Technical Field
The application relates to an automatic control method, in particular to an automatic ignition and flameout interlocking protection control method for a heat accumulating type gas hot blast stove.
Background
The gas hot blast stove is used as main equipment for providing temperature for blast furnace smelting, the gas burner is a hot blast stove heating device, the normal operation of the burner plays an important role in the safety of the hot blast stove, the burner is a main stage of safety accidents in the initial stage of ignition, and if flameout occurs in the ignition process of the burner, a large amount of gas is easily caused to gather in the stove, so that the explosion accidents occur.
The prior art mainly has the following defects: (1) In the ignition process, a person is mainly used for penetrating the liquefied gas ignition gun into the ignition hole of the burner to ignite the gas burner, the liquefied gas ignition gun is easy to flameout in winter with low air temperature, and the ignition gun is required to be pulled out manually to plug the ignition hole after the ignition is finished; (2) The main gas pipeline of the hot blast stove is provided with a gas shut-off valve, the branch pipe burner gas pipeline is respectively provided with a gas flow regulating valve and a manual butterfly valve, and because the interlocking protection of the quick cut valve does not have the operation regulation when the furnace is ignited, when the burner flame detector cannot detect flame, the manual butterfly valve needs to be manually closed, the reaction time is delayed, the gas concentration in the furnace is easily increased rapidly, thereby causing explosion accidents and having larger safety risks.
Therefore, the research and development of the gas hot-blast stove burner flameout interlocking protection control method is a key for solving the problem, and the gas poisoning and burner flameout explosion accidents in the manual ignition process of the regenerative gas hot-blast stove are effectively solved.
Disclosure of Invention
Aiming at the defects of the prior art, the application provides the automatic ignition and flameout interlocking protection control method for the heat accumulating type gas hot blast stove, realizes the ignition and flameout interlocking protection of the gas hot blast stove, and solves the safety risks that the ignition of the existing liquefied gas is unsmooth under the condition of low air temperature, and the manual butterfly valve at the root of the burner is manually closed to cut off the gas in the process of ignition.
The technical scheme for solving the technical problems is as follows: an automatic ignition and flameout interlocking protection control method for a heat accumulating type gas hot blast stove is characterized by comprising the following steps of: comprises the steps of,
s1, starting a system: self-checking and purging by a Programmable Logic Controller (PLC);
s2, igniting a diesel oil burner;
s3, igniting the nearest burner; the PLC controls and opens an air flow controller of an air pipeline corresponding to the burner, then opens a three-eccentric butterfly valve and a gas flow controller of a gas pipeline corresponding to the burner, a flame detection device corresponding to the burner detects signals, and a flame video monitoring device confirms that the burner is successfully ignited and heats up after seeing the burner flame;
s4, sequentially igniting other burners: when the furnace temperature reaches 800 ℃, other burners are sequentially ignited;
s5, closing the diesel oil burner: all burners burn normally, after the furnace temperature is stabilized above 950 ℃, the diesel burner stops working, and the cooling blower starts a blowing cooling mode, and the ignition work of the hot blast stove burner is finished.
In the optimization scheme, the method further comprises the step of S0 pre-checking: checking the combustion equipment to ensure that all the equipment operates normally and has safe operating conditions, opening all the reserved doors on the furnace body, ensuring that the chimney at the rear part is smooth, and ensuring the negative pressure of the hot blast stove system to ensure that the gas flow controllers and the three eccentric butterfly valves in front of all the burners are closed.
Further, the above-mentioned burner is a diesel burner.
Further, in the step S2, the normal ignition standard is that the signal is detected by the ignition of the diesel engine, and the flame of the diesel engine is clearly seen in the flame video monitoring device.
Further, in the step S2, the ignition is prompted to be normal, and the process proceeds to the step S3 after the combustion is performed for 30 minutes.
Further, three burners are set to be a 3# burner, a 2# gas burner and a 1# gas burner from far to near from the diesel burner.
Further, when the burner is ignited,: and then, the PLC controls and opens a gas pipeline three-eccentric butterfly valve corresponding to the burner, the valve opening of the gas pipeline three-eccentric butterfly valve is opened to 10% -30%, and the gas flow controller is opened to enable the gas flow to be 5% -25%.
Further, in the step S3, if the flame detection device corresponding to the burner does not detect the flame signal within 10 seconds, and the flame video monitoring device does not observe the burner flame, the PLC controls the re-ignition.
Further, the re-ignition is as follows: and the PLC automatically closes the triple eccentric butterfly valve and the gas flow controller, the air flow controller of the air pipeline is adjusted to increase the air quantity of the combustion-supporting fan, the revolution of the main exhaust fan is increased to adjust the negative pressure of the hearth system, after the hearth is purged for 5 minutes, the step S2 and the step S3 are repeated, and the burner is re-ignited.
Further, in the step S4, after the furnace temperature reaches 800 ℃, the 2# gas burner is ignited, and when the 3# gas burner and the 2# gas burner are normally combusted and stabilized, and the furnace temperature is more than 900 ℃, the 1# gas burner is ignited.
Compared with the prior art, the application realizes the functions of automatic ignition, automatic on-line flame monitoring, remote on-line real-time monitoring of the combustion condition of the burner and automatic protection of the flameout interlock of the burner, and enhances the safety of the ignition and operation of the gas hot blast stove.
Drawings
FIG. 1 is a schematic view of the structure of the hot blast stove apparatus of the present application.
Fig. 2 is an ignition flow chart of the present application.
Detailed Description
The application is further described below with reference to the drawings and the detailed description.
For the purposes of the following detailed description, it is to be understood that the application may assume various alternative variations and step sequences, except where expressly specified to the contrary. Furthermore, all numbers expressing, for example, quantities of ingredients used in the specification and claims, other than in any operating example or where otherwise indicated, are to be understood as being modified in all instances by the term "about". At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.
Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the application are approximations, the numerical values set forth in the specific examples are reported as precisely as possible. Any numerical value, however, inherently contains certain errors necessarily resulting from the standard deviation found in their respective testing measurements.
It should also be understood that any numerical range recited herein is intended to include all sub-ranges subsumed therein. For example, a range of "1 to 10" is intended to include all subranges between (and including) the stated minimum value of 1 and the stated maximum value of 10, that is, having a minimum value equal to or greater than 1 and a maximum value equal to or less than 10.
In the present application, the use of the singular includes the plural and plural encompasses singular, unless specifically stated otherwise. In addition, in the present application, unless explicitly stated otherwise, the use of "or" means "and/or", even if "and/or" may be explicitly used in some cases. Further, in the present application, the use of "a" or "an" means "at least one" unless specifically stated otherwise. For example, "a" first material, "a" coating composition, etc., refer to one or more of any of these items.
For better illustration, the side facing the hot air furnace is the distal end, i.e., the right side is the distal end and the left side is the proximal end in fig. 1.
As shown in fig. 1, the application relies on an ignition device with interlocking protection for a gas hot blast stove, comprising a stove inner unit, a stove outer unit and a Programmable Logic Controller (PLC).
The furnace unit comprises a diesel oil burner 15, a flame video monitoring device 16, a temperature detector and a plurality of burners, and is arranged in a hearth of the hot blast stove. The temperature detector is located in the hearth of the hot blast stove, and can be one or a plurality of temperature detectors, which are not shown in fig. 1 because of being smaller. The burner, in this case a diesel burner 15, is arranged on the furnace wall with an ignition direction at an angle of 90 ° to the nozzle direction. The burner is arranged on the furnace wall, the root of the burner is connected with the outlet of the gas pipeline 5, and the root of the burner is provided with a flame detection device 14. The flame detection device 14 is a flame detection probe. In this embodiment, the flame video monitoring device 16 is a flame monitoring television camera.
The off-furnace unit comprises an air duct 13 and a gas duct 5.
From the near to the far, the air pipeline 13 is provided with an air flow controller 3 and an air flowmeter 4, and an outlet of the air pipeline 13 is connected with the near end of an outlet of the gas pipeline 5. The near section of the air pipeline 13 is connected with a fan 12 through an air pressure gauge 11.
The gas pipeline 5 is provided with a gas flow controller 6, a gas flowmeter 7 and a triple eccentric butterfly valve 8 from the near to the far, and the part of the air pipeline 13, which enters the gas pipeline 5, is between the triple eccentric butterfly valve 8 and the gas pipeline 5.
In this embodiment, three burners are set from far to near to the diesel burner 15 as a 1# gas burner 91, a 2# gas burner 92, and a 3# burner 93. Therefore, the air pipeline 13 and the gas pipeline 5 are respectively provided with three corresponding branch pipelines, the branch pipeline of each air pipeline 13 is provided with the air flow controller 3 and the air flowmeter 4, and the branch pipeline of each gas pipeline 5 is provided with the gas flow controller 6, the gas flowmeter 7 and the three-eccentric butterfly valve 8.
The programmable controller PLC is arranged in the field explosion-proof operation cabinet and is respectively electrically connected with the diesel oil burner 15, the flame video monitoring device 16, the temperature detector, the air flow controller 3, the air flow meter 4, the gas flow controller 6, the gas flow meter 7 and the triple eccentric butterfly valve 8, the PLC is in data connection with the central control system, and the PLC transmits field device data to the central control room to realize central control remote control.
As shown in fig. 2, the application relates to an automatic ignition and flameout interlocking protection control method for a heat accumulating type gas hot blast stove, which comprises the following specific working processes:
s0, pre-inspection
The operator must check the combustion equipment to ensure that all equipment is operating properly and has safe operating conditions.
And opening all the reserved doors on the furnace body to ensure that a chimney at the rear part is smooth, and the negative pressure of the hot blast furnace system is ensured.
All parts of the ignition flameout device must normally operate, and the gas flow controllers 6 and the three-eccentric butterfly valves 8 in front of all burners are closed.
S1, starting system
(1) Programmable controller PLC self-checking
The programmable controller PLC self-checks whether the combustion air pressure and the main gas pressure are normal or not, and the PLC timer is normal or not.
(2) Purging
S2, igniting diesel oil burner
Preparation of the diesel engine before ignition: the central control operator starts the oil pump, circulates (without a nozzle) to adjust the oil pressure to 1kg, and the oil pump works normally, so that the ignition operation of the diesel engine 15 can be performed.
When the burner is on fire stably, the signal is detected by the fire detection of the diesel burner 15, the central control picture prompts that the ignition is normal, the burner flame is clearly seen in the flame video monitoring device 16, and after the burner is burned for 30 minutes, the burner is debugged to the optimal state: the flame outline of the diesel oil burner 15 is clear, the flame is stable, and after the flame signal is detected by the flame of the diesel oil burner 15, the central control prompts the ignition gas to allow and the ignition operation of the gas burner can be performed.
If the ignition is not shown to be normal, the ignition of the diesel engine is repeated.
S3, igniting the nearest burner
In this embodiment, three burners are set from far to near to the diesel burner 15 as 3# burner 93, 2# gas burner 92, and 1# gas burner 91. The burner closest to the diesel burner 15 is the burner # 3 93.
(1) Ignition 3# burner 93
The PLC controls and opens the air flow controller 3 of the air pipeline 13 corresponding to the 3# burner 93, and enables the valve opening to be opened to 5% -20%, and the central control shows that the air flow is normal.
Then, the PLC controls and opens the triple eccentric butterfly valve 8 of the gas pipeline 5 corresponding to the No. 3 burner 93, and opens the valve to 10% -30%, and opens the gas flow controller 6, so that the gas flow is 5% -25%.
(2) Fire detection
Once the corresponding flame detection device 14 of the 3# burner 93 detects a signal and the flame video monitoring device 16 sees the burner flame, the ignition success of the 3# burner 93 is determined.
If the flame signal is not detected by the root flame detection device 14 of the 3# burner 93 within 10 seconds, and meanwhile, if the burner flame is not observed by the flame video monitoring device 16, which means that the 3# burner 93 is not ignited, the PLC control automatically closes the three-eccentric butterfly valve 8 and the gas flow controller 6 corresponding to the 3# burner 93. And the air flow controller 3 for adjusting the air pipeline 13 increases the air quantity of the combustion-supporting fan 12, increases the revolution of the main exhaust fan 12, adjusts the negative pressure of the hearth system, sweeps the hearth for 5 minutes, repeats the step S2 and the step S3, and re-ignites the No. 3 burner 93.
(3) Heating and raising temperature
After the ignition of the burner No. 3 93 is successfully determined, the furnace is gradually heated after burning for 10 minutes. The three eccentric butterfly valve 8 corresponding to the 3# burner 93 is adjusted to 50%, the gas flow controller 6 is adjusted to 30%, the air flow valve is adjusted to 70% (the gas flow is controlled to 2000 m) 3 ～5000m 3 Air flow control 1500m 3 ～4000m 3 )。
S4, sequentially igniting other burners
When the furnace temperature reaches 800 ℃, the air pipeline 13 branch pipeline and the gas pipeline 5 branch pipeline of the No. 2 gas burner 92 are started, and the method is the same as that of the No. 3 burner 93.
When the 3# burner 93 and the 2# gas burner 92 burn normally and stably, and the furnace temperature is more than 900 ℃, the 1# gas burner 91 is ignited, and the method for igniting the 1# gas burner 91 is the same as that for igniting the 2# gas burner 92.
S5, closing the diesel oil burner
When all 3 burners are burned normally and the furnace temperature is stabilized above 950 ℃, the diesel burner 15 stops working and the cooling blower 12 starts the blowing cooling mode.
And (5) finishing the ignition work of the hot blast stove burner.
It should be noted that, in this embodiment, a technique known in the art is not described in detail.
While the application has been described in detail and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that various changes can be made therein without departing from the spirit and scope of the application.

Claims (10)

1. An automatic ignition and flameout interlocking protection control method for a heat accumulating type gas hot blast stove is characterized by comprising the following steps of: comprises the steps of,
s1, starting a system: self-checking and purging by a Programmable Logic Controller (PLC);
s2, igniting a diesel oil burner;
s3, igniting the nearest burner; the PLC controls and opens an air flow controller of an air pipeline corresponding to the burner, then opens a three-eccentric butterfly valve and a gas flow controller of a gas pipeline corresponding to the burner, a flame detection device corresponding to the burner detects signals, and a flame video monitoring device confirms that the burner is successfully ignited and heats up after seeing the burner flame;
s4, sequentially igniting other burners: when the furnace temperature reaches 800 ℃, other burners are sequentially ignited;
s5, closing the diesel oil burner: all burners burn normally, after the furnace temperature is stabilized above 950 ℃, the diesel burner stops working, and the cooling blower starts a blowing cooling mode, and the ignition work of the hot blast stove burner is finished.
2. The method for controlling the automatic ignition and flameout interlocking protection of the regenerative gas hot blast stove according to claim 1, which is characterized by comprising the following steps: the method also comprises the step S0 of pre-checking: checking the combustion equipment to ensure that all the equipment operates normally and has safe operating conditions, opening all the reserved doors on the furnace body, ensuring that the chimney at the rear part is smooth, and ensuring the negative pressure of the hot blast stove system to ensure that the gas flow controllers and the three eccentric butterfly valves in front of all the burners are closed.
3. The method for controlling the automatic ignition and flameout interlocking protection of the regenerative gas hot blast stove according to claim 1, which is characterized by comprising the following steps: the burner is a diesel burner.
4. The method for controlling automatic ignition and flameout interlocking protection of the regenerative gas hot blast stove according to claim 3, wherein the method comprises the following steps: in the step S2, the ignition normal standard is that the ignition detection signal of the diesel oil burner is detected, and the burner flame is clearly seen in the flame video monitoring device.
5. The method for controlling the automatic ignition and flameout interlocking protection of the regenerative gas hot blast stove according to claim 4, which is characterized by comprising the following steps: in the step S2, the ignition is prompted to be normal, and the combustion is carried out for 30 minutes and then the step S3 is carried out.
6. The method for controlling automatic ignition and flameout interlocking protection of the regenerative gas hot blast stove according to claim 3, wherein the method comprises the following steps: the number of the burners is three, and the burners are set to be 3# burners, 2# gas burners and 1# gas burners from far to near from the diesel oil burner.
7. The method for controlling automatic ignition and flameout interlocking protection of the regenerative gas hot blast stove according to claim 6, which is characterized in that: when the burner is ignited: and then, the PLC controls and opens a gas pipeline three-eccentric butterfly valve corresponding to the burner, the valve opening of the gas pipeline three-eccentric butterfly valve is opened to 10% -30%, and the gas flow controller is opened to enable the gas flow to be 5% -25%.
8. The method for controlling the automatic ignition and flameout interlocking protection of the regenerative gas hot blast stove according to claim 1, which is characterized by comprising the following steps: in the step S3, if the flame detection device corresponding to the burner does not detect the flame signal within 10 seconds, and the flame video monitoring device does not observe the burner flame, the PLC controls the re-ignition.
9. The method for controlling the automatic ignition and flameout interlocking protection of the regenerative gas hot blast stove according to claim 8, which is characterized by comprising the following steps: the re-ignition is: and the PLC automatically closes the triple eccentric butterfly valve and the gas flow controller, the air flow controller of the air pipeline is adjusted to increase the air quantity of the combustion-supporting fan, the revolution of the main exhaust fan is increased to adjust the negative pressure of the hearth system, after the hearth is purged for 5 minutes, the step S2 and the step S3 are repeated, and the burner is re-ignited.
10. The method for controlling automatic ignition and flameout interlocking protection of the regenerative gas hot blast stove according to claim 6, which is characterized in that: in the step S4, after the furnace temperature reaches 800 ℃, the 2# gas burner is ignited, and after the 3# gas burner and the 2# gas burner are normally combusted and stabilized and the furnace temperature is more than 900 ℃, the 1# gas burner is ignited.
CN202311088501.5A 2023-08-28 2023-08-28 Automatic ignition and flameout interlocking protection control method for heat accumulating type gas hot blast stove Pending CN117109027A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202311088501.5A CN117109027A (en) 2023-08-28 2023-08-28 Automatic ignition and flameout interlocking protection control method for heat accumulating type gas hot blast stove

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202311088501.5A CN117109027A (en) 2023-08-28 2023-08-28 Automatic ignition and flameout interlocking protection control method for heat accumulating type gas hot blast stove

Publications (1)

Publication Number Publication Date
CN117109027A true CN117109027A (en) 2023-11-24

Family

ID=88796093

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202311088501.5A Pending CN117109027A (en) 2023-08-28 2023-08-28 Automatic ignition and flameout interlocking protection control method for heat accumulating type gas hot blast stove

Country Status (1)

Country Link
CN (1) CN117109027A (en)

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