Automatic decoking method, controller and system for boiler

Abstract

The invention provides an automatic decoking method, controller and system for a boiler. The method comprises the steps that the liquid level height of a medicine tank is detected; when the liquid level height is larger than a first preset value and smaller than a second preset value, medicine dispensing raw materials, water and compressed air are added into the medicine tank, and the medicine dispensing raw materials and the water are stirred; when the liquid level height is greater than or equal to a second preset value, stopping adding the dispensing raw materials, the water and the compressed air into the medicine tank, and stopping stirring; the boiler is subjected to chemical spraying decoking operation, chemical spraying is stopped when the liquid level height is smaller than or equal to a first preset value, the dosage raw materials, water and compressed air are added into the chemical tank, and the dosage raw materials and the water are stirred. Therefore, dispensing is achieved, manual participation is not needed in the spraying process, and labor cost and personnel safety risks are reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of coal furnaces, and in particular to a method, controller and system for automatic decoking of boilers. Background Art

[0002] Coal, as the combustion source for thermal power generation, accounts for about 80% of the operating costs of thermal power plants.

[0003] In order to reduce the coking and fouling on the heating surface of the boiler, the boiler needs to use decoking agents reasonably, which can effectively reduce the coking and fouling phenomenon and improve the safety and economy of boiler operation. However, the current use of boiler liquid decoking agents mainly relies on manual preparation and injection, which has a low degree of automation, high labor costs and high personal safety risks. Summary of the invention

[0004] To solve the above problems, the present invention provides a boiler automatic decoking method, controller and system, which realize automatic preparation of syrup and automatic spraying of boiler liquid degumming agent through remote automatic control without manual intervention, thereby reducing labor costs, operating costs and personnel safety risks.

[0005] A first aspect of the present disclosure provides a method for automatic decoking of a boiler, the method comprising: detecting a liquid level height of a medicine tank; when the liquid level height is greater than a first preset value and less than a second preset value, adding medicine raw materials, water and compressed air to the medicine tank, and stirring the medicine raw materials and water; when the liquid level height is greater than or equal to the second preset value, stopping adding medicine raw materials, water and compressed air to the medicine tank, and stopping stirring; performing a decoking operation on the boiler by spraying medicine, and when the liquid level height is less than or equal to the first preset value, stopping spraying medicine, adding medicine raw materials, water and compressed air to the medicine tank, and stirring the medicine raw materials and water.

[0006] In this way, by setting the first preset value and the second preset value, the liquid level is between the first preset value and the second preset value, and the pharmaceutical raw materials and water are automatically mixed to form a medicine, so that the preparation of the medicine does not require human intervention, and after the liquid level reaches the second preset value, the spray gun is automatically turned on to spray the prepared medicine, so that the spraying process does not require human intervention, thereby making the entire medicine preparation and spraying process fully automatic, reducing labor costs, operating costs, and reducing personnel safety risks.

[0007] In some embodiments, the mass ratio of the pharmaceutical raw materials to water is 1:3.

[0008] This setting helps to enhance the descorching effect of the configured potion.

[0009] In some embodiments, the pharmaceutical raw materials and water are added alternately multiple times until the mass ratio reaches 1:3.

[0010] This arrangement makes it easier to fully mix the raw materials for the medicine and water, thereby improving the descorching properties of the medicine.

[0011] In some embodiments, the method includes: receiving a first liquid level signal, where the first liquid level signal is used to indicate that the liquid level height is less than or equal to a first preset value.

[0012] With such an arrangement, by receiving the first liquid level signal to determine whether the liquid level is less than or equal to the first preset value, it is helpful to monitor the low liquid level situation in the medicine tank in real time.

[0013] In some embodiments, the method includes: receiving a second liquid level signal, where the second liquid level signal is used to indicate that the liquid level height is greater than or equal to a second preset value.

[0014] With this arrangement, by receiving the second liquid level signal to determine whether the liquid level is greater than or equal to the second preset value, it is helpful to monitor the high liquid level situation in the medicine tank in real time.

[0015] In some embodiments, the method includes: not receiving a first liquid level signal and a second liquid level signal, which are used to indicate that the liquid level height is greater than a first preset value and less than a second preset value.

[0016] With such an arrangement, by not receiving the first liquid level signal and the second liquid level signal, it can be judged that the liquid medicine in the medicine tank is neither too much nor too little, which helps the dosing pump to continue dosing and the agitator to continue stirring, thereby obtaining a medicine solution mixed with the dosage raw materials and water in a mass ratio of 1:3.

[0017] A second aspect of the present disclosure provides a controller, which is used to execute the method described in the first aspect.

[0018] A third aspect of the present disclosure provides a boiler automatic decoking system, the system comprising: a medicine tank;

[0019] A dosing pump, connected to the medicine tank, for adding medicine to the medicine tank;

[0020] A water adding pipe, connected to the medicine tank, for adding water to the medicine tank;

[0021] A compressed air machine connected to the medicine tank and used to inject compressed air into the medicine tank;

[0022] A stirrer is arranged in the medicine tank and is used to stir the medicine raw materials and water;

[0023] A spray gun connected to the medicine tank;

[0024] A controller is used to control a medicine tank, a medicine adding pump, a water adding pipe, a compressed air machine, a stirrer and a spray gun to execute the method described in the first aspect.

[0025] With such an arrangement, when the decoking agent is automatically prepared, the controller controls the dosing pump to add medicine and the water pipe to add water, and then controls the compressed air machine and the agitator to operate automatically, so as to automatically mix the preparation raw materials and water in the medicine tank to form a medicine solution, and finally controls the opening of the spray gun to decoke the prepared medicine solution, thereby realizing the full automation of the preparation, injection and monitoring of the decoking agent, with a high degree of automation, low labor costs and low personal safety risks.

[0026] In some embodiments, a low liquid level switch and a high liquid level switch are provided in the medicine tank, the liquid level at which the low liquid level switch is located is a first preset value, and the liquid level at which the high liquid level switch is located is a second preset value;

[0027] When the liquid level is less than or equal to a first preset value, the dosing pump and the water pipe are started; when the liquid level is greater than the first preset value and less than a second preset value, the dosing pump, the water pipe, the compressed air machine and the agitator are started; when the liquid level is greater than or equal to the second preset value, the dosing pump, the water pipe and the compressed air machine are stopped, and the agitator and the spray gun are started.

[0028] Such arrangement enables the automatic start and stop of the dosing pump and the water pipe, as well as the automatic start and stop of the agitator and the spray gun, when the liquid level is at the two critical values ​​of the first preset value and the second preset value, so that the preparation of the medicine in the medicine tank can be achieved by fully automatic proportioning based on the change of the liquid level, effectively improving the efficiency of medicine preparation and reducing labor costs and personal safety risks.

[0029] In some embodiments, a dosing solenoid valve is provided at the connection between the dosing pump and the medicine tank, a water adding solenoid valve is provided at the connection between the water adding pipe and the medicine tank, a compressed air solenoid valve is provided on the compressed air machine, an agitator solenoid valve is provided on the agitator, and a spray gun solenoid valve is provided on the spray gun.

[0030] In this way, by setting up multiple solenoid valves, the control system can automatically control the automatic start and stop of the dosing pump, water adding pipe, air compressor, agitator and spray gun through electrical signals, thereby realizing fully automatic operation, making the degree of automation higher, saving costs and improving the preparation efficiency of the medicine.

[0031] Compared with the prior art, the present invention has the following advantages: preparation and injection of boiler liquid decoking agent do not require human participation, thereby reducing labor costs, operating costs, and personnel safety risks.

[0032] Other features and advantages of the present disclosure will be described in the following description, and partly become apparent from the description, or be understood by implementing the present disclosure. The purpose and other advantages of the present disclosure can be realized and obtained by the structures pointed out in the description, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the embodiments of the present disclosure or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0034] Figure 1 It is a schematic diagram of a process flow of a boiler automatic decoking method provided by an embodiment of the present disclosure;

[0035] Figure 2 is a structural block diagram of a boiler automatic decoking system provided by an embodiment of the present disclosure;

[0036] Figure 3 is a structural block diagram of a decoking agent control cabinet provided in an embodiment of the present disclosure;

[0037] Figure 4 It is a schematic diagram of the structure of an electronic device provided by an embodiment of the present disclosure. DETAILED DESCRIPTION

[0038] In order to make the purpose, technical solution and advantages of the embodiments of the present disclosure clearer, the technical solution in the embodiments of the present disclosure will be clearly and completely described below in conjunction with the drawings in the embodiments of the present disclosure. Obviously, the described embodiments are part of the embodiments of the present disclosure, not all of the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present disclosure.

[0039] The following is a brief introduction to some concepts that may be involved in the embodiments of the present disclosure.

[0040] Distributed Control System (DCS): An industrial automation control system that connects sensors, controllers, and equipment scattered throughout the factory through a network to monitor and control the operation of the boiler.

[0041] like Figure 1 As shown, Figure 1 The following is a flow chart of a method for automatic decoking of a boiler provided in an embodiment of the present disclosure, wherein the method comprises the following steps:

[0042] S100, detecting the liquid level height of the medicine tank.

[0043] S200. When the liquid level is greater than the first preset value and less than the second preset value, add the pharmaceutical raw materials, water and compressed air into the medicine tank to stir the pharmaceutical raw materials and water.

[0044] In this embodiment, when the liquid level has not reached the first preset value or the second preset value, the first liquid level signal and the second liquid level signal are not received, indicating that the liquid level is greater than the first preset value and less than the second preset value. The liquid level of the medicine in the medicine tank is moderate, and the preparation raw materials, water and compressed air can continue to be added at this time. However, it should be noted that the preparation raw materials and water are still being stirred at this time, until the liquid level reaches the second preset value, then the addition of preparation raw materials and water is stopped, and the addition of compressed air is also stopped, and stirring is continued. At this time, the medicine can be decoked until the liquid level is lower than the first preset value, then the medicine stops being decoked, and the preparation raw materials and water continue to be added, and compressed air continues to be added. After the liquid level of the medicine in the medicine tank reaches the second preset value again, the addition of preparation raw materials and water is stopped, and the addition of compressed air is also stopped, and the medicine is used for decoking.

[0045] S300: When the liquid level is greater than or equal to a second preset value, stop adding the pharmaceutical raw materials, water and compressed air into the medicine tank, and stop stirring.

[0046] In the embodiment of the present disclosure, a second preset value for monitoring the liquid level height is provided so that a high critical value of the liquid level is provided in the medicine tank, and a second liquid level signal is received, the second liquid level signal being used to indicate that the liquid level height is greater than or equal to the second preset value; so that the liquid level height information is received in a timely manner through the second preset value, so that after the liquid level is higher than the second preset value, the addition of medicine and water into the medicine tank is stopped, and compressed air is injected into the medicine tank, so that the medicine raw materials and water are stirred under the compressed air, so that the medicine raw materials and water are fully mixed in a ratio of 1:3 to form a decoking agent solution.

[0047] It should be noted that the addition of chemicals and water will not start until the decoking process using the chemical solution and the stirring process are stopped synchronously. Moreover, after the liquid level is higher than the second preset value, as the chemical solution is used, the liquid level gradually drops below the first preset value, at which time the addition of chemicals and water will start, and the cycle will be repeated.

[0048] S400, spraying medicine to decoke the boiler, and stopping spraying medicine when the liquid level is less than or equal to a first preset value, adding medicine raw materials, water and compressed air into the medicine tank, and stirring the medicine raw materials and water.

[0049] In this embodiment, by setting a first preset value for monitoring the liquid level height, a low liquid level critical value is provided in the medicine tank, so as to receive a first liquid level signal. The first liquid level signal is used to indicate that the liquid level height is less than or equal to the first preset value, so as to timely receive the liquid level height information through the first preset value, so as to automatically add the pharmaceutical raw materials into the medicine tank after the liquid level is lower than the first preset value, and stop using the medicine for decoking at this time.

[0050] Exemplarily, the pharmaceutical raw materials are added to the medicine tank for 1 minute, and water is added to the medicine tank for 3 minutes, and the process is repeated several times until a mass ratio of the pharmaceutical raw materials to water is 1:3.

[0051] Based on the above method, the embodiment of the present disclosure also provides a boiler automatic decoking system corresponding to the above method, such as Figure 2 Shown and Figure 3 , Figure 2 is a structural block diagram of a boiler automatic decoking system provided by an embodiment of the present disclosure, Figure 3 It is a structural block diagram of a decoking agent control cabinet provided in an embodiment of the present disclosure. The boiler automatic decoking system includes a controller and a decoking agent control cabinet. The controller is also a DCS system, and the DCS system is integrated in the decoking agent control cabinet.

[0052] The boiler automatic decoking system also includes a medicine tank, a medicine adding pump, a water adding pipe, a compressed air machine, an agitator and a spray gun. The controller is used to control the medicine tank, the medicine adding pump, the water adding pipe, the compressed air machine, the agitator and the spray gun to perform the above method. The medicine adding pump is connected to the medicine tank for adding medicine to the medicine tank; the water adding pipe is connected to the medicine tank for adding water to the medicine tank; the compressed air machine is connected to the medicine tank for injecting compressed air into the medicine tank; the agitator is arranged in the medicine tank for stirring the medicine raw materials and water; the spray gun is connected to the medicine tank.

[0053] In some embodiments, a low liquid level switch and a high liquid level switch are provided in the medicine tank, the liquid level at which the low liquid level switch is located is a first preset value, and the liquid level at which the high liquid level switch is located is a second preset value; when the liquid level is less than or equal to the first preset value, the dosing pump and the water adding pipe are started; when the liquid level is greater than the first preset value and less than the second preset value, the dosing pump, the water adding pipe, the compressed air machine and the agitator are started; when the liquid level is greater than or equal to the second preset value, the dosing pump, the water adding pipe and the compressed air machine are stopped, and the agitator and the spray gun are started.

[0054] In some embodiments, a dosing solenoid valve is provided at the connection between the dosing pump and the medicine tank, a water adding solenoid valve is provided at the connection between the water adding pipe and the medicine tank, a compressed air solenoid valve is provided on the compressed air machine, and the compressed air solenoid valve is connected to the decoking agent dosing tank, such as Figure 2 The stirrer is provided with a stirrer electromagnetic valve, and the spray gun is provided with a spray gun electromagnetic valve.

[0055] In some embodiments, there are two spray guns, namely spray gun No. 1 and spray gun No. 2. Each spray gun is equipped with a flow meter, and a spray gun No. 1 isolation door is installed on spray gun No. 1. The solenoid valves on the spray guns include spray gun No. 1 solenoid valve and spray gun No. 2 solenoid valve to control the start and stop of spray gun No. 1 and spray gun No. 2.

[0056] It should be noted that the dosing pump, compressed air solenoid valve, agitator solenoid valve, dosing solenoid valve, water adding solenoid valve, high liquid level switch, low liquid level switch, No. 1 spray gun solenoid valve, No. 2 spray gun solenoid valve, No. 1 spray gun and No. 2 spray gun are all connected to the decoking agent control cabinet, such as Figure 3 Shown are device 1, device 2, device n and device 10.

[0057] In this embodiment, the DCS system remotely controls the operation mode of the field equipment:

[0058] Start the dosing pump; open the dosing solenoid valve for 1 minute and the water solenoid valve for 3 minutes, alternately, to achieve a mass ratio of 1:3 between the agent and water;

[0059] The "low liquid level switch" of the decoking agent tank is activated, and the low liquid level signal disappears;

[0060] Open the compressed air solenoid valve;

[0061] Open the agitator solenoid valve, and the agitator rotates under the drive of compressed air to stir the medicine and water to form a medicine solution;

[0062] The "high liquid level switch" of the decoking agent tank is activated, and the high liquid level signal is established. The high liquid level signal is sent to the decoking agent control cabinet, and the signal is transmitted to the DCS system. The DCS system issues instructions: stop the dosing pump, close the dosing solenoid valve, and close the water adding solenoid valve;

[0063] The DCS system issues a command: open the solenoid valve of spray gun No. 1, open the solenoid valve of spray gun No. 2; monitor the flow meters of spray guns No. 1 and 2 and indicate that they are normal;

[0064] The "low liquid level switch" of the decoking agent tank is activated, the solenoid valve of the No. 1 spray gun is closed, the solenoid valve of the No. 2 spray gun is opened, and the flow meters of the No. 1 and No. 2 spray guns are monitored and indicate 0;

[0065] The "low liquid level switch" of the decoking agent tank is activated, the agitator solenoid valve is interlocked and closed, the agitator stops rotating, and the compressed air solenoid valve is interlocked and closed;

[0066] The "low liquid level switch" of the decoking agent tank is activated, and the interlock starts the dosing pump; the cycle is repeated in sequence until the DCS system issues a stop command.

[0067] Therefore, through the coupling of electrical components and DCS, the whole process of decoking agent dispensing, injection and monitoring is fully automated. The start / stop instructions, on / off instructions, high / low level signals, flow signals and equipment status signals of the field equipment are integrated through the field control cabinet bus and transmitted to the centralized control operation DCS system.

[0068] It should be noted that the spray gun here sprays into the flue gas in the boiler furnace. The flue gas achieves the decoking effect after contacting the heating surface of the boiler. No human intervention is required and the spraying is carried out through the reserved holes designed for the boiler.

[0069] Based on the same inventive concept as the above disclosed content, the present disclosure also provides an electronic device 2000. Figure 4 As shown, Figure 4 The electronic device 2000 provided by the present disclosure is a structural block diagram. The electronic device 2000 of the embodiment of the present disclosure includes at least one processor 210 and at least one memory 220 electrically connected. The memory 220 is electrically connected to the processor 210, wherein the memory 220 stores instructions that can be executed by the at least one processor 210, and the instructions are executed by the at least one processor 210 so that the at least one processor 210 can execute the above method.

[0070] It should be noted that the electrical connection between the above-mentioned units does not necessarily mean the connection between lines. An indirect connection method can be applied to the embodiments of the present disclosure as long as the purpose of the present disclosure is achieved.

[0071] Based on the same inventive concept, the present disclosure also provides a computer storage medium, a computer program is stored on the computer-readable storage medium, and when the computer program is executed by the processor, the method described above is performed. The storage medium may include: a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, and other media that can store program codes.

[0072] Although the present disclosure has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present disclosure.

Claims

1. A method for automatic decoking of boilers, characterized in that: The method comprises: Detect the liquid level of the medicine tank; When the liquid level height is greater than the first preset value and less than the second preset value, adding the pharmaceutical raw materials, water and compressed air into the medicine tank to stir the pharmaceutical raw materials and water; When the liquid level is greater than or equal to a second preset value, stop adding the pharmaceutical raw materials, water and compressed air into the medicine tank, and stop stirring; The boiler is subjected to a spraying decoking operation, and when the liquid level height is less than or equal to a first preset value, the spraying is stopped, and the medicine raw materials, water and compressed air are added to the medicine tank, and the medicine raw materials and water are stirred.

2. The method according to claim 1, characterized in that The mass ratio of the pharmaceutical raw materials to water is 1:

3.

3. The method according to claim 2, characterized in that The pharmaceutical raw materials and water are added alternately multiple times until the mass ratio reaches 1:

3.

4. The method according to claim 1, characterized in that: The method comprises: receiving a first liquid level signal, wherein the first liquid level signal is used to indicate that the liquid level height is less than or equal to a first preset value.

5. The method according to claim 4, characterized in that The method comprises: receiving a second liquid level signal, where the second liquid level signal is used to indicate that the liquid level height is greater than or equal to a second preset value.

6. The method according to claim 5, characterized in that The method includes: not receiving a first liquid level signal and a second liquid level signal, which are used to indicate that the liquid level height is greater than a first preset value and less than a second preset value.

7. A controller, characterized in that: The controller is used to execute the method according to any one of claims 1 to 6.

8. A boiler automatic decoking system, the system comprising: Medicine jars; A dosing pump, connected to the medicine tank, for adding medicine to the medicine tank; A water adding pipe, connected to the medicine tank, for adding water to the medicine tank; A compressed air machine connected to the medicine tank and used to inject compressed air into the medicine tank; A stirrer is arranged in the medicine tank and is used to stir the medicine raw materials and water; A spray gun connected to the medicine tank; A controller is used to control a medicine tank, a medicine adding pump, a water adding pipe, an air compressor, a stirrer and a spray gun to execute the method as described in any one of claims 1 to 6.

9. The system according to claim 8, characterized in that A low liquid level switch and a high liquid level switch are provided in the medicine tank, the liquid level at which the low liquid level switch is located is a first preset value, and the liquid level at which the high liquid level switch is located is a second preset value; When the liquid level is less than or equal to a first preset value, the dosing pump and the water pipe are started; when the liquid level is greater than the first preset value and less than a second preset value, the dosing pump, the water pipe, the compressed air machine and the agitator are started; when the liquid level is greater than or equal to the second preset value, the dosing pump, the water pipe and the compressed air machine are stopped, and the agitator and the spray gun are started.

10. The system according to claim 8, characterized in that A dosing solenoid valve is provided at the connection between the dosing pump and the medicine tank, a water adding solenoid valve is provided at the connection between the water adding pipe and the medicine tank, a compressed air solenoid valve is provided on the compressed air machine, a stirrer solenoid valve is provided on the stirrer, and a spray gun solenoid valve is provided on the spray gun.

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