KR20000019730A - System for controlling soot blower of boiler and controlling method thereof - Google Patents

Abstract

PURPOSE: A soot blower control system of a boiler is provided to maintain the efficiency of a boiler in the best condition and to minimize the amount of vapors used for blowing by blowing the polluted part automatically by assuming the polluted degree of each part of the inner part of a boiler. CONSTITUTION: A boiler(6) shaped in a bridge is composed of: a combustion furnace(16) placed on the right side of the boiler and having a reheater(20) and a primary super heater(22) on each divided part of the partition; and an economizer(24) is extended to the combustion furnace and arranged in spiral structure. A secondary super heater(28) placed on the upper part of the boiler is divided into 3 parts of a pendant super heater(34) placed to face right from the left side, a platen super heater(36) and a super tube(30) which are arranged sequentially. A soot blower(38) performs cleaning according to the polluted degree in the boiler by being installed to move inside the boiler. The vapors are obtained by bypassing in the reheater.

Description

Soot blower control system of boiler and its control method

The present invention relates to a soot blower control system of a boiler and a control method thereof, and more particularly, to be deposited on the surface of a heat pipe disposed in a combustion furnace or a flue of a boiler generated during combustion of a boiler. The present invention relates to a soot blower control system and a control method of a boiler for automatically controlling a soot blower for cleaning a soot by spraying steam or air.

A boiler is a device that generates steam by heating water with heat generated when burning fuel inside a combustion furnace made of a closed steel container. The steam is rotated by the steam to obtain electric power or heat the supercooled water with hot water or heating. The device used for.

In such a boiler, a plurality of heat pipes in which steam circulates is arranged, and soot generated during combustion is deposited on the surfaces of these heat pipes, thereby lowering the heat transfer rate, which reduces the overall efficiency and load rate of the boiler. Therefore, in order to maintain high thermal efficiency and load rate, the soot deposited on the surface of the heat pipe must be removed.

For this purpose, a soot blower is provided in the combustion furnace of the boiler, and it is used to remove the soot by bypassing the high pressure steam circulating the heat pipe. It is preferable to use as little as possible because it is lowered.

The above-mentioned soot blower is proposed to be operated manually after the worker determines that the inside of the boiler is contaminated, to be operated by a timer, and to be operated by evaluating the operating state of the boiler.

However, when the soot blower is operated in a conventionally known manner, since the soot blowing operation is performed by visual judgment and intuitive judgment, there is no basis for judging the amount or contamination of the soot deposited on the surface of the heat pipe. In addition, there is a problem in that the heat transfer efficiency of the boiler heat transfer surface is rapidly lowered due to contaminants due to an increase in the blowing time, or not blowing at the blowing time.

In order to solve the above problems, the present invention is to infer the degree of contamination of each part of the boiler by automatically blowing the contaminated parts by minimizing the steam used for blowing and furthermore the soot blower control of the boiler that can maintain the best boiler efficiency It is an object to provide a system.

In addition, by repeatedly performing the self-learning algorithm by feeding back the blowing result, it is another object of the present invention to provide a control method capable of optimally operating the soot blower even if the state of the fuel changes or the operating conditions change after the boiler operation. do.

In order to achieve the above object, the present invention proposes the following control system and control method.

That is, distributed control means for controlling a boiler having a soot blower for cleaning the contaminants attached to the surface of the heat transfer pipe with steam; Program logic control means in association with said soot blower for operation; A soot blowing computer connected to the distribution control means for inputting or transmitting various data and parameters; A signal interface module to which operation data of a boiler are input from the plurality of sensors and the distribution control means; An ordering tool module for inputting information of various parameters from the program logic control means by the suit blowing computer; A thermodynamic modeling module that receives various data and parameters from the signal interface module and the ordering tool module and generates actual values for contamination evaluation; A model identification module which receives various data and parameters from the signal interface module and the ordering tool module and generates a reference value for contamination evaluation; If the result of comparing the actual value and the reference value with a driving knowledge base tool is determined to be a contamination of a specific part, the blowing interface and initial driving command of the soot blower are transmitted to the distributed control means through the signal interface module. Logic control means for operating said soot blower.

In addition, in order to evaluate the pollution reduction effect after the operation of the soot blower, the effect evaluation module for receiving the actual value and the reference value from the thermodynamic modeling module and the model identification module to determine the soot blowing effect using the operation knowledge base tool It may be provided.

In particular, the self-learning algorithm module connected to the effect evaluation module and the pollution degree reasoning module automatically corrects the parameters of the soot blowing determination result transmitted from the effect evaluation module and transmits the parameters to the effect evaluation module and the reasoning module. Can be.

In addition, a state monitoring module connected between the self-acquisition algorithm module and the pollution degree inference module may display a boiler sensor value and an inference result value on a screen.

One end is connected to the bypass line of the signal interface module and the pollution inference module, and the other end is connected to the soot blowing computer so that a state and alarm printer module may be provided to output the value of the boiler sensor and the inference result. have.

The plurality of sensors may include an outlet temperature of exhaust gas generated in a boiler to infer pollution in the combustion furnace, an amount of gas damper opening of a reheater in the heat transfer pipe, a nose outlet steam temperature of the combustion furnace, and an outlet of the combustion furnace. Gas temperature and heat absorption inside the furnace can be detected.

The method for controlling the soot blower based on such a control system includes the operation data of the boiler obtained by the signal interface module from a plurality of sensors and distributed control means, and the order from the program logic control means by the soot blowing computer. Generating actual values by obtaining various parameters input to the tool module and mapping the thermodynamic modeling module; Generating a reference value by mapping parameters acquired from the signal interface module and the ordering tool module to a model identification module; Determining a pollution degree using an operation knowledge base tool in a pollution degree inference module obtained with the actual value and the reference value; When the specific part inside the boiler is contaminated, the blowing position of the soot blower and the initial driving command are transmitted to the distributed control means through the signal interface module so that the program logic control means operates the soot blower to clean the inside of the boiler. Steps; Correcting the actual value by obtaining the data of detecting the cleaning state inside the boiler through the signal interface module; Determining a soot blowing effect by mapping the modified actual value and the reference value by using an operation knowledge base tool by an effect evaluation module obtained by a thermodynamic modeling module and a model checking module; The result of the effect determination is sent to the self-learning algorithm module to automatically correct the parameters of the pollution inference module and the effect evaluation module to automatically clean the contaminants in the boiler.

In particular, the exhaust gas outlet temperature of the boiler, the gas damper opening amount of the reheater in the heat transfer pipe, the nose outlet steam temperature of the combustion furnace, and the combustion furnace in order to generate actual values and reference values for evaluating the pollution degree of the combustion furnace. It detects the outlet gas temperature and the heat absorption rate inside the combustion furnace.

Further, in determining the pollution degree of the combustion furnace based on the actual value and the reference value, the exhaust gas outlet temperature of the boiler, the gas damper opening amount of the reheater in the heat transfer pipe, the nose outlet steam temperature of the combustion furnace, and the outlet of the combustion furnace It can be determined by combining the gas temperature and the heat absorption rate inside the combustion furnace.

The cleaning position of the soot blower may be a nose section, a second superheater section, a reheater section, a primary first superheater section and an air heater section of the combustion furnace.

Meanwhile, the cleaning operation may be performed in consideration of the flow of flue gas by combustion so that the soot coming off after the cleaning of any one part is attached to the other part cleaned beforehand so as to increase the pollution degree.

1 is a schematic view showing a cleaning structure of a boiler and a soot blower of a boiler according to the present invention;

2 is a block diagram showing a soot blower control system according to the present invention.

3 is a flowchart illustrating a soot blower control method according to each step.

4 is a view schematically showing the overall structure of a steam station equipped with a boiler.

Explanation of symbols on the main parts of the drawings

6: boiler 16: combustion furnace

38: soot blower 42: distributed control means

44: program logic control means 46: suit blowing computer

48: printer 50: signal interface module

52: Order Tool Module 54: Thermodynamic Modeling Module

56: model identification module 58: pollution inference module

60: driving knowledge base tool 62: module for evaluating effects

64: self-learning algorithm module 66: status monitoring module

68: status and alarm printer module

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a schematic view showing a combustion furnace structure of a boiler according to the present invention and a cleaning position of a soot blower, FIG. 2 is a block diagram showing a soot blower control system according to the present invention, and FIG. 3 is a soot blower according to each step. 4 is a flowchart illustrating a control method, and FIG. 4 schematically shows the overall structure of a steam motive station equipped with a boiler.

As can be seen in FIG. 4, the steam source includes a boiler 6 having a combustion furnace 4 for burning fossil fuel supplied from a coal tank 2, and a heat transfer tube having a constant shape inside the tooth 6. 8) is disposed, the steam flowing inside the heat pipe (8) absorbs the heat generated in the combustion furnace (4) and converts it into high pressure steam, and then the steam rotates the steam turbine (10) to the steam turbine ( 10 is connected to the generator 12 is configured to generate power. Here, the flue gas generated when the fossil fuel is burned is discharged through the stack 14.

More specifically, the boiler 6 has a structure as shown in FIG.

That is, the boiler 6 receiving the fossil fuel from the side has a bridge shape, the combustion furnace 16 on the left side, and the partition 18 on the right side, and the reheater 20 and the first heater. A primary super heater 22 is disposed, and an economizer 24 is disposed below the reheater 20 and the first superheater 22. The tubes of this coal mill 24 extend into the furnace 16 and are arranged in a spiral structure.

An air heater 26 mounted at the exhaust gas outlet of the boiler 6 is preheated with combustion air sent to the boiler 6 using the waste heat of the exhaust gas.

In particular, the second superheater 28 disposed on top of the boiler 6 has a reheater tube 32 whose one end of the superheater tube 30 is connected to the steam turbine 10 and which extends to the reheater 20. One end of is connected to the steam turbine 10 in a state in which it is disposed in contact with one end of the superheater tube (30).

Here, the second superheater (28) is divided into three parts, the pendant super heater (34), platen super heater (36) and the superheater tube from the left side of the boiler (6) toward the right side 30 are arranged in order.

On the other hand, the soot blower 38 is mounted so as to be able to move the interior of the boiler 6 so that the cleaning operation is performed according to the pollution degree inside the boiler (6). The steam used at this time is obtained by bypassing in the reheater (20).

In the boiler 6 having such a structure, heat generated when the fossil fuel is combusted in the combustion furnace 16 is generated, and water is evaporated by the heat to form a saturated steam state. By passing through the superheater (22) (28) to the high-pressure steam to rotate the steam turbine 10 primarily.

The rotated steam is then converted to steam having a pressure close to the high pressure steam as it is reheated in the reheater 20 and rotates the steam turbine 10 through the reheater tube 32. The steam is condensed in a condenser, not shown, converted to water and then introduced to the coal mill 24 where it is preheated and fed to the boiler 6.

Inevitably generated soot in the combustion process is discharged through the exit of the furnace with the exhaust gas, some of the dust is collected after the discharge can be post-processing, but the rest is the heat transfer tube inside the combustion furnace 16, that is, the second superheater ( 28), it is deposited in the reheater 20, the first superheater 22 and the pelletizer 24 or attached to the combustion furnace 16 or to the flue gas outlet.

Due to the soot deposited, the steam flowing inside the heat pipe cannot be properly heat exchanged with the heat of the combustion furnace 16, so that the soot blower control system according to the present invention is proposed as shown in FIG. Decontamination will be removed automatically. In particular, the position of determining the pollution degree in the boiler is the nose part A, the second superheater part B, the reheater part C, the first superheater part D, and the air heater part E of the combustion furnace.

A plurality of sensors 40 are installed in the above-described boiler 6, and distributed control means 42 connected with these sensors 40 to obtain various data when the boiler 6 is operated, The program logic control means 44 is connected to the distribution control means 42 to control the operation of the soot blower 38.

In addition, the soot blowing computer 46 is connected to the distribution control means 42 and program logic control means by mapping parameters to the boiler state obtained by the various sensors 40 or data indicated by the operator. This causes 44 to operate the soot blower 38 and all results can be output by the printer 48 connected to the soot blowing computer 46.

In more detail, the connection and the interrelationship of various modules for soot blowing are described. The operating data of the boiler 6 from the plurality of sensors 40 and the distributed control means 42 is connected to the signal interface module 50. Is obtained by the soot blowing computer 46, and information of various parameters is input from the program logic control means 44 into the ordering tool module 52.

Here, various data and parameters obtained for determining the pollution degree of the boiler 6 are reference values input for determining the actual value according to the operation of the boiler 6 and the operation time of the soot blower 38.

In particular, when determining the pollution degree of the combustion furnace 16, the actual operation data of the boiler 6 is input and the pollution degree is determined by comparing the actual value and the reference value respectively calculated according to five reference elements. Here, the five reference elements are the outlet flue gas temperature of the furnace, the gas damper opening amount of the reheater in the heat pipe, the nose outlet steam temperature of the furnace, the outlet gas temperature of the furnace and the inside of the furnace. It is heat absorption rate.

The actual values and reference values thus obtained are generated by the thermodynamic modeling module 54 and the model identification module 56 respectively associated with the signal interface module 50 and the ordering tool module 52.

The thermodynamic modeling module 54 and the model identification module 56 are simultaneously connected to the pollution degree reasoning module 58, and the pollution degree reasoning module 58 is connected to the specific part using the operation knowledge base tool 60 connected thereto. Determine the contamination level of

The determined result value is transmitted to the distributed control means 42 by the program logic control means 44 by transmitting the blowing position and the initial driving command of the soot blower 38 through the signal interface module 50. ) To work.

On the other hand, the thermodynamic modeling module 54 and the model identification module 56 are simultaneously linked to the effect evaluation module 62, the operation knowledge base tool 60 is connected to the effect evaluation module 62 It is used to determine the effect after soot blowing.

In particular, the self-learning algorithm module 64 connected to the effect evaluation module 62 and the pollution degree inference module 58 at the same time automatically converts the parameters of the soot blowing determination result transmitted from the effect evaluation module 62. The correction is fed back to the effect evaluation module 62 and the pollution degree reasoning module 58.

Between the self-acquisition algorithm module 64 and the pollution degree inference module 58, a state monitoring module 66 for displaying a sensor value and an inference result value for detecting a pollution level of the boiler is connected to the screen.

One end of the status and alarm printer module 68 is connected to the bypass line of the signal interface module 50 and the pollution degree inference module 58, and the other end is connected to the soot blowing computer 46. Various data obtained by the sensor 40 and the inference result are outputted.

A method of controlling a soot blower based on such a control system is illustrated in FIG. 3.

The first step 100 is the operating data of the boiler obtained from the plurality of sensors 40 and the distributed control means 42 to the signal interface module 50 and the program logic control means by the soot blowing computer 46. The actual values are generated by obtaining various parameters inputted from the 44 to the ordering tool module 52 and mapping them in the thermodynamic modeling module 54.

Subsequently, the second step 200 is to map the parameters acquired from the signal interface module 50 and the ordering tool module 52 to the model identification module 56 to generate a reference value.

The third step 300 is to determine the pollution degree by using the operation knowledge base tool 60 in the pollution degree reasoning module 58 obtained the actual value and the reference value, and in the fourth step 400 a specific portion inside the boiler 6. Is transmitted, the program logic control means 44 causes the soot blower 38 to transmit the blowing position of the soot blower 38 and the initial driving command to the distributed control means 42 through the signal interface module 50. It operates to clean the inside of the boiler (6).

After cleaning the inside of the boiler 6, the data of detecting the state is again obtained through the signal interface module 50 and after the fifth step 500 of correcting the actual value, the thermodynamic modeling module 54 and the model identification module Step 600 of judging the soot blowing effect by mapping the effect evaluation module 62 which obtains the actual value and the reference value modified at 56 by using the operation knowledge base tool 60, and then the result of the effect determination is It is transmitted to the self-learning algorithm module 64 to automatically clean the soot inside the boiler 6 in a step 700 of automatically modifying the parameters of the pollution inference module 58 and the effect evaluation module 62. This cleaning operation is preferably carried out repeatedly according to the pollution degree of the boiler (6).

In particular, the exhaust gas outlet temperature of the boiler 6, the opening amount of the gas damper of the reheater 20 in the heat transfer pipe, and the combustion furnace 16 in order to generate actual values and reference values for determining the pollution degree of the combustion furnace 16. The nose outlet steam temperature of the furnace, the outlet gas temperature of the combustion furnace 16 and the heat absorption rate inside the combustion furnace 16 are detected by the plurality of sensors 40 or distributed by the control means 42 and the chute by the operator. It is input to the blowing computer 46.

In addition, in determining the pollution degree of the combustion furnace 16 by the actual value and the reference value in the pollution degree reasoning module 58, the exhaust gas outlet temperature of the boiler 6 and the gas damper opening amount of the reheater 20 in the heat transfer pipe. And a combination of the nose outlet steam temperature of the combustion furnace 16, the outlet gas temperature of the combustion furnace 16, and the heat absorption rate inside the combustion furnace 16.

In addition, the cleaning work is performed in consideration of the flow of the flue gas in the combustion so that the soot coming off after the cleaning of any one part is attached to the other part cleaned beforehand so as to increase the pollution degree.

As described above, the embodiment of the present invention substantially solves the conventional problems.

That is, various sensors are installed inside the boiler, and the data obtained by the controller are distributed control means, program logic control means, soot blowing computer and a plurality of modules to determine the degree of contamination of each part of the boiler. Based on this, the soot blower can be moved to a contaminated location to automatically remove the soot, thus reducing the consumption of steam.

In addition, it is possible to improve the efficiency and load ratio of the boiler by removing the soot deposited by determining the time to remove the soot at the appropriate time.

Claims (11)

When a plurality of heat pipes arranged for heat exchange inside the boiler are contaminated by the soot generated during combustion, a suit for washing the contaminants attached to the surface of the heat pipe as steam by measuring the degree of contamination with a plurality of sensors installed in the boiler. In the blower, Distributed control means (42) for controlling the boiler (6); Program logic control means (42) associated with the distribution control means (42) to cause the soot blower (38) to operate; A soot blowing computer 46 connected to the distribution control means 42 for inputting or transmitting various data and parameters; A signal interface module (50) for inputting operating data of the boiler (6) from the plurality of sensors (40) and the distribution control means (42); An ordering tool module 52 for inputting information of various parameters from the program logic control means 44 by the suit blowing computer 46; A thermodynamic modeling module 54 which receives various data and parameters from the signal interface module 50 and the ordering tool module 52 and generates actual values for contamination evaluation; A model identification module 56 which receives various data and parameters from the signal interface module 50 and the ordering tool module 52 and generates a reference value for contamination evaluation; If the result of comparing the actual value and the reference value using the operation knowledge base tool 60 is determined to be a contamination of a specific part, the blowing interface and the initial driving command of the soot blower are distributed through the signal interface module 50. A soot blower control system for a boiler, characterized in that the program logic control means (44) operates the soot blower (38) by transmitting it to a control means (42). The operational knowledge base tool according to claim 1, wherein the actual value and the reference value are transmitted from the thermodynamic modeling module 54 and the model identification module 56 to evaluate the pollution reduction effect after the soot blower 38 operates. The soot blower control system of the boiler characterized by the effect evaluation module 62 which determines the soot blowing effect using 60. The self-learning algorithm module 64, which is connected to the effect evaluating module 62 and the pollution degree inference module 58, is used to determine the result of the soot blowing determination transmitted from the effect evaluating module 62. Soot blower control system of the boiler, characterized in that for automatically modifying the parameters to transmit the effect evaluation module 62 and the inference module (58). According to claim 1 or claim 2 or claim 3, wherein the status monitoring module connected between the self-acquisition algorithm module 64 and the pollution degree inference module 58 to display a boiler sensor value and the inference result value on the screen ( 68. A soot blower control system of a boiler, characterized in that it is provided. 5. The boiler according to claim 1 or 4, wherein one end is connected to the bypass line of the signal interface module 50 and the pollution degree reasoning module 58, and the other end is connected to the soot blowing computer 46. Soot blower control system of the boiler, characterized in that it is provided with a state and alarm printer module (68) to output the value of the sensor and the inference result. The method of claim 1, wherein the plurality of sensors 40, the outlet temperature of the flue-gas generated in the boiler 6 to infer the pollution inside the combustion furnace, and the gas damper opening amount of the reheater 20 in the heat transfer pipe The soot blower control system of the boiler characterized in that it detects the nose outlet steam temperature of the combustion furnace 16, the outlet gas temperature of the combustion furnace (16) and the heat absorption rate in the combustion furnace (16). When a plurality of heat pipes arranged for heat exchange inside the boiler is contaminated by the soot generated during combustion, the method for controlling a soot blower installed in the furnace to wash the contaminants attached to the outer surface of the heat pipes as steam. , The operating data of the boiler 6 obtained from the plurality of sensors 40 and the distributed control means 42 to the signal interface module 50 and the program logic control means 44 by the soot blowing computer 46. Generating (100) actual values by acquiring various parameters input from the order tool module (52) to the thermodynamic modeling module (54); (200) generating parameters by mapping parameters acquired from the signal interface module (50) and the ordering tool module (52) to the model identification module; Determining (300) the pollution degree by using the operation knowledge base tool (60) in the pollution degree reasoning module (58) which obtained the actual value and the reference value; Program logic control means by transmitting the blowing position of the soot blower 38 and the initial driving command to the distribution control means 42 through the signal interface module 50 when a specific part inside the boiler 6 is contaminated. Cleaning (400) the interior of the boiler (6) by causing 44 to operate the soot blower (38); A step (500) of correcting the actual value by obtaining the data of detecting the cleaning state inside the boiler (6) through the signal interface module (50); Determining the soot blowing effect by mapping the corrected actual value and the reference value by using the operation knowledge base tool 60 by the effect evaluation module 62 obtained by the thermodynamic modeling module 54 and the model identification module 56. 600; The result of the effect determination is transmitted to the self-learning algorithm module 64 to automatically modify the parameters of the pollution inference module 58 and the effect evaluation module 62 to remove contaminants in the boiler 6. Soot blower control method of the boiler, characterized in that the automatic cleaning. 8. The exhaust gas outlet temperature of the boiler 6, the gas damper opening amount of the reheater 20 in the heat transfer pipe, in order to generate actual values and reference values for determining the pollution degree of the combustion furnace 16, A method for controlling a soot blower of a boiler, characterized in that it detects the nose outlet steam temperature of the combustion furnace, the outlet gas temperature of the combustion furnace, and the heat absorption rate in the combustion furnace. 9. The gas damper opening according to claim 7 or 8, wherein the exhaust gas outlet temperature of the boiler 6 and the reheater 20 in the heat transfer pipe are determined in determining the pollution degree of the combustion furnace 16 based on the actual value and the reference value. A soot blower of a boiler characterized in that it is determined by combining the quantity, the nose outlet steam temperature of the combustion furnace 16, the outlet gas temperature of the combustion furnace 16, and the heat absorption rate inside the combustion furnace 16. Control method. The cleaning position of the soot blower (38) according to claim 7 or 8 or 9, wherein the nose portion (A), the second superheater portion (B), the reheater portion (C), and the first superheat of the combustion furnace. Soot blower control method of the boiler, characterized in that the base (D) and the air heater (E). 11. The cleaning operation according to claim 10, characterized in that the cleaning operation is performed in consideration of the flow of the flue gas of the combustion furnace 16 so that the soot coming off after the cleaning of any one part is attached to the other part which has been previously cleaned and does not increase the pollution degree. How to control the soot blower of the boiler.