JP6987659B2 - Boiler control device and control method - Google Patents

Description

The present invention relates to a boiler control device and a control method.

In general, by-product gas generated in refineries and ironworks contains flammable components such as carbon monoxide and hydrogen as well as inert components such as nitrogen, and the calorific value of the by-product gas is also generated at each place. It is a low-calorie gas that differs in and may change in composition from time to time. Typical by-product gases include, for example, coke oven gas (COG) generated in a coke oven and blast furnace gas (BFG) generated in a blast furnace. Some of these by-products are used as fuel for boilers in thermal power generation facilities. Some of these boilers employ a type of boiler that co-combusts various fuels (for example, COG, BGF, coal, oil, etc.), and in each boiler, the mixing ratio of various fuels depends on the fuel supply status. As it is supplied and burned, the mixing ratio of these various fuels may be changed on the way.

When BFG and COG are used as the fuel for the boiler, since the BFG and COG contain harmful gases (carbon monoxide, etc.), it is necessary to give priority to burning all the fuel gas by burning the boiler. .. If the air supply amount required for combustion is not set in advance by fuel adjustment when the fuel mixing ratio is changed in the middle, it deviates from the appropriate value and the unburned content, NOx, CO, etc. exceed the environmental regulation value. It could have happened.
Conventionally, as a method for reducing NOx in exhaust gas discharged from a boiler and unburned fuel in ash, for example, a method disclosed in Patent Document 1 is known. In Patent Document 1, when a mixed fuel gas in which different types of fuel are mixed is used, the air supply amount based on the combustion ratio according to the fuel supply amount is calculated for each fuel type, and the calculated air supply amount is used for the entire boiler. A method of calculating the required air supply amount and making it possible to supply an appropriate amount of air to a burner divided into a plurality of compartments is disclosed.

Japanese Patent No. 3755979

However, in the method disclosed in Patent Document 1 described above, under conditions where application at a preset combustion ratio has not been confirmed, an appropriate air supply amount or other operation amount related to the combustion state is always calculated. In some cases, NOx and unburned fuel exceeding the environmental regulation values may be generated.

The present invention has been made in view of such circumstances, and even when a plurality of types of fuel are burned in a boiler, NOx and unburned fuel content are more reliably suppressed within the environmental regulation value. It is an object of the present invention to provide a control device and a control method for a boiler capable of the like.

The first aspect of the present invention includes a plurality of crushers and a plurality of burners for burning the fuel, and co-firing a plurality of types of fuels including pulverized fuel produced by crushing the solid fuel with the crusher. A control device applied to a possible boiler, which is a storage means for storing a plurality of basic information in which control command values for burning the plurality of types of fuel are set for each operating condition of the boiler. It is provided with a basic information extraction means for extracting the basic information corresponding to the current operating condition of the boiler from the storage means, and a determination means for determining the control command value using the extracted basic information. The operating status of the boiler includes at least one of the combination of the plurality of types of fuel supplied to the boiler, the number of operating units of the crusher, and the operating number of the burner, and the control command value is supplied to the boiler. It is a boiler control device including at least one of a first control command value regarding an air supply amount and a second control command value regarding a horizontal ejection angle of the gas ejected from the burner into the boiler.

According to the above configuration, a plurality of basic information is stored in the storage means for each operating status of the boiler, and the basic information corresponding to the current operating status of the boiler is acquired from these basic information stored in the storage means. , The first control command value regarding the amount of air supplied to the boiler based on the acquired basic information, and the second regarding the horizontal ejection angle of the gas ejected from the burner into the boiler (hereinafter, simply referred to as "gas ejection angle"). 2 At least one of the control command values is determined.
In this case, the operating condition of the boiler is assumed to include at least one of a combination of a plurality of types of fuel supplied to the boiler, the number of crushers and crushers in operation, and the number of burners in operation. Further, as the basic information, control command values are set so that NOx and unburned fuel content are within the environmental regulation values in the operating conditions of each corresponding boiler.
In this way, basic information is prepared according to the combination of multiple types of fuel supplied to the boiler, the number of crushers in operation, the number of burners in operation, etc., and the basic information according to the current operating status of the boiler is provided. It is used to determine the control command value related to the combustion state, specifically, the control command value related to the amount of air supplied to the boiler and the control command value related to the gas ejection angle. It is possible to control the combustion state appropriately and finely. This makes it possible to more reliably keep the NOx and unburned fuel content contained in the exhaust gas discharged from the boiler within the environmental regulation values.

In the boiler control device, the operating condition of the boiler may further include at least one of a load which is a steam generation ratio with respect to a rated steam generation amount of the boiler and a type of fuel supplied to the boiler.

In this way, by providing basic information according to the load of the boiler (ratio of steam generation to the rated steam generation amount) and the type of solid fuel supplied to the boiler, more detailed air supply amount and gas ejection angle can be obtained. Control can be realized.

In the boiler control device, the storage means is associated with the co-firing rate of each fuel in the combination of the plurality of types of fuel supplied to the boiler and the correction value of the control command value for each operating condition. A plurality of correction information is stored, and the correction information extracting means for extracting the correction information corresponding to the current operating condition of the boiler from the storage means is provided, and the determination means uses the extracted correction information. The correction value corresponding to the current co-firing rate of the plurality of types of fuel may be acquired, and the acquired correction value may be used to correct the control command value determined by using the basic information.

In this way, a plurality of correction information in which the co-firing rate of each fuel in the combination of the plurality of types of fuel supplied to the boiler and the correction value of the control command value are associated with each other is prepared in advance for each operating condition of the boiler. Since the correction value is acquired using the correction information according to the current boiler operating condition and the control command value determined from the basic information is corrected based on the acquired correction value, not only the boiler operating condition but also the fuel co-firing Appropriate air supply and / or gas ejection angle can also be determined in terms of rate. This makes it possible to more reliably keep NOx and unburned fuel content below the environmental specified values.
The above "co-firing rate of each fuel" is defined as, for example, the ratio of the fuel input amount of each fuel to the fuel input amount of the total fuel in which a plurality of types of fuels are combined (the total value obtained by adding the fuel input amounts of each fuel). Will be done.

The boiler control device may further include an updating means for updating the correction information based on actual operation data.

In this way, by updating the correction information based on the actual operation data, it is possible to further improve the control accuracy of the air supply amount and / or the gas ejection angle.

A second aspect of the present invention is a boiler including the plurality of crushers, the plurality of burners, and the control device for the boiler described above.

A third aspect of the present invention includes a plurality of crushers and a plurality of burners for burning the fuel, and co-firing a plurality of types of fuels including pulverized fuel produced by crushing the solid fuel with the crusher. It is a control method applied to a possible boiler, and is a control method for the current boiler from among a plurality of basic information in which control command values for burning the plurality of types of fuel are set for each operating condition of the boiler. It has a step of extracting the basic information corresponding to the operating condition and a step of determining the control command value using the extracted basic information, and the operating condition of the boiler is supplied to the boiler. The control command value includes at least one of a combination of a plurality of types of fuel, the number of operating units of the crusher, and the operating number of the burner, and the control command value is from the first control command value regarding the amount of air supplied to the boiler and the burner. It is a boiler control method including at least one of the second control command values regarding the ejection angle of the gas ejected into the boiler with respect to the horizontal direction.

According to the present invention, even when a plurality of types of fuel are burned in a boiler, it is possible to more reliably suppress NOx and unburned fuel content within the environmental regulation values.

It is a figure which showed the vertical sectional view of the boiler which concerns on one Embodiment of this invention. It is a horizontal (horizontal) sectional view of FIG. It is a figure which showed the enlarged view of the solid fuel burning burner shown in FIG. It is a figure which shows the outline of the air supply system which supplies the air to the fuel burner of FIG. It is a functional block diagram of the control device which concerns on one Embodiment of this invention. It is a figure for demonstrating the operation state of a boiler, basic information, and correction information. It is a figure which showed an example of the basic information. It is a figure which showed an example of the correction information. It is a flowchart which showed the processing procedure executed by the control apparatus which concerns on one Embodiment of this invention.

Hereinafter, an embodiment of the boiler control device and control method according to the present invention will be described with reference to the drawings. In the present embodiment, as the boiler to which the control device and the control method of the boiler are applied, a solid fuel-fired boiler, specifically, a solid fuel-fired burner using pulverized coal (coal which is a powder solid fuel) as fuel is used. However, the application of the boiler control device and control method of the present invention is not limited to this.

FIG. 1 is a vertical sectional view of the boiler 10 according to an embodiment of the present invention, and FIG. 2 is a horizontal (horizontal) sectional view of FIG. As shown in FIG. 1, the boiler 10 creates a reducing atmosphere in the region from the burner section 12 to the additional air charging section (hereinafter referred to as “AA section”) 14 by injecting air into the furnace 11 in multiple stages. We are trying to reduce the NOx of combustion exhaust gas.

As shown in FIGS. 1 and 2, the boiler 10 is supplied with one type of fuel or a plurality of types of fuel, and the supplied fuel is burned or co-firing. When co-firing a plurality of types of fuel, the co-firing rate is used as one of the values indicating the ratio of each fuel in the total fuel in which the plurality of types of fuel are combined. The co-firing rate is defined as the ratio of the fuel input amount of each fuel to the fuel input amount of the total fuel in which a plurality of types of fuels are combined (hereinafter referred to as "total fuel input amount"). For example, the co-firing rate of pulverized coal fuel in a combination of a plurality of types of fuel including pulverized coal fuel is expressed by the following formula.

Co-firing rate of pulverized coal = fuel input amount of pulverized coal fuel / total fuel input amount = (calorific value of pulverized coal fuel x flow rate of pulverized coal fuel) / (calorific value of total fuel x total fuel flow rate)

In the following description, the pulverized coal co-firing rate is referred to as "coal co-firing rate".
Examples of the fuel other than the pulverized coal used as the fuel of the boiler 10 include coke oven gas (COG: Cokes Oven Gas), blast furnace gas (BFG: Blast Furnace Gas), oil (light oil) and the like.
In the present embodiment, a case where pulverized coal (fine pulverized fuel) and blast furnace gas (BFG) are co-fired as an example of co-firing by combining a plurality of types of fuels will be described as an example, but the combination of fuels is not limited to this example.
The boiler 10 according to the present embodiment includes a plurality of crushers 27, pulverized coal (fine pulverized fuel) in which solid fuel such as coal is crushed by the crusher 27, pulverized coal-fired burner 20 into which air is introduced, and blast furnace gas (BFG). ) And a BFG-fired burner 24 into which air is charged, and an additional air injection nozzle 15 in which additional air is charged into the AA unit 14. In the pulverized coal-fired burner 20, a part of the secondary air is introduced around the pulverized coal mixture transport pipe 16 and the pulverized coal mixture transport pipe 16 for mixing and transporting the pulverized coal with the primary air from the crusher 27. The air supply duct 17 is connected so as to supply. Further, a BFG transport pipe 26 and an air supply duct 17 are connected to the BFG-fired burner 24 so as to supply a part of the secondary air around the BFG fuel. Further, an air supply duct 17 for supplying a part of the secondary air is connected to the additional air injection nozzle 15 of the AA unit 14. Secondary air supplied to the air supply duct 17 from, for example, a blower (not shown) and preheated to a predetermined temperature by an air preheater ((not shown)) is supplied.

The boiler 10 according to the present embodiment is a burner in which a pulverized coal-fired burner 20 or a BFG-fired burner 24 is arranged at each corner portion (see FIG. 2) in the horizontal direction of the boiler 10 in each stage provided in the vertical vertical direction. A unit 12 is provided, and the pulverized coal fuel and air are charged into the furnace 11 from each pulverized coal-fired burner 20, and the BFG and air are charged into the furnace 11 from the BFG-fired burner 24. Alternatively, a swirling combustion method (see FIG. 2) in which a plurality of swirling flames are formed is adopted.

FIG. 3 is an enlarged view of the pulverized coal-fired burner 20 shown in FIG. Although the pulverized coal-fired burner 20 will be described here as an example, the BFG-fired burner 24 has the same configuration.

As shown in FIG. 3, the pulverized coal-fired burner 20 includes a fuel burner 21 for charging pulverized coal and primary air, and ports 30 for secondary air injection arranged above and below the fuel burner 21, respectively. There is. In order to enable the air flow rate adjustment for each port, the secondary air input port 30 adjusts the air flow rate for each secondary air supply line branched from the air supply duct 17, for example, as shown in FIG. A damper 40 whose opening degree can be adjusted is provided as a means.

As shown in FIG. 3, the fuel burner 21 of the pulverized coal-fired burner 20 surrounds the rectangular primary port 22 for charging the pulverized coal fuel conveyed by the primary air and the periphery of the primary port 22. It is provided with a secondary port 23 for inputting a part of the secondary air. As shown in FIG. 4, the secondary port 23 is also provided with a damper 40 whose opening degree can be adjusted as a flow rate adjusting means. The primary port 22 may be circular or elliptical.

Further, the fuel burner 21 is configured so that the angle can be adjusted. Specifically, as shown in FIG. 3, the fuel burner 21 has a swirling flame in a furnace 11 formed in each stage of the burner portion 12 in order to adjust the steam temperature generated by the boiler 10 to a predetermined value. The angle (burner angle) α with respect to the horizontal direction of the gas ejected from the tip of the fuel burner 21 can be appropriately changed in the vertical vertical direction so that the position can be changed.
Further, each air supply duct 17 connected to the additional air injection nozzle 15 of the AA unit 14 is also provided with a damper (not shown) whose opening degree can be adjusted as a secondary air flow rate adjusting means.

The boiler 10 further includes a control device 50 (see FIG. 5) for controlling the boiler 10. The control device 50 is a control device that controls the entire boiler. For example, the number of the above-mentioned crushers 27 is set according to the steam generation ratio (hereinafter referred to as “load”) with respect to the rated steam generation amount of the boiler 10. Control function, control function to control the number of operating fuel burners 21 ignited and burning, function to control the burner angle α of the fuel burner 21, control the pulverized coal fuel flow rate and BFG fuel flow rate supplied to the boiler 10. It has a plurality of functions such as a function to control the total amount of secondary air supplied to the boiler 10 and a function to control the air distribution between the burner unit 12 and the AA unit 14 by controlling the damper 40 whose opening degree can be adjusted. ..

The control device 50 is composed of, for example, a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), a computer-readable storage medium, and the like. As an example, a series of processes for realizing various functions are stored in a storage medium or the like in the form of a program, and the CPU reads this program into a RAM or the like to execute information processing / arithmetic processing. As a result, various functions are realized. The program is installed in a ROM or other storage medium in advance, is provided in a state of being stored in a computer-readable storage medium, or is distributed via a wired or wireless communication means. Etc. may be applied. The computer-readable storage medium is a magnetic disk, a magneto-optical disk, a CD-ROM, a DVD-ROM, a semiconductor memory, or the like.

FIG. 5 is a functional block diagram showing mainly the functions for controlling the air supply amount among the functions included in the control device 50. As shown in FIG. 5, the control device 50 includes a storage unit 51, a basic information extraction unit 52, a correction information extraction unit 53, and a determination unit 54 as main configurations. In the following description, the air supply amount is the total air supply amount of the primary air and the secondary air combined, but in the present embodiment, the primary air supply amount is the pulverized coal supply amount as the amount for transporting the pulverized coal. Since it is constant with respect to the above, the air supply amount will be described as indicating the secondary air supply amount in particular.

A plurality of basic information and a plurality of correction information are stored in the storage unit 51. In the storage unit 51, a plurality of basic information is provided for each operating condition of the boiler 10. Here, the operating status of the boiler 10 includes at least one of a combination of a plurality of types of fuel supplied to the boiler 10, the number of operating crushers, and the number of burners in operation (the number of fuel burners 21 ignited and burned). .. Preferably, the operating condition of the boiler 10 may further include at least one of the load of the boiler 10 and the type of coal supplied to the boiler 10.
For example, as shown in FIG. 6, as the operating status of the boiler, for example, a plurality of basic information prepared for each operating number of crushers (1 to 3) and for each coal type (A to C) (1 to 3). In this embodiment, it is set by the Fx function). That is, a total of nine basic information Fx1_1 to Fx1_9 are created in advance and stored in the storage unit 51.

Basic information Fx1-1-1 to Fx1_9 are, for example, NOx and NOx contained in the exhaust gas discharged from the boiler 10 when the boiler 10 is operated in each operating condition with the co-firing rate of each fuel as a reference value (for example, 50%). A control command value is set for setting the air supply amount (for example, the secondary air supply amount) so that the unburned content is within the environmental regulation value.
For example, the basic information is information in which a factor affecting NOx and unburned fuel content is associated with a control command value for adjusting the secondary air supply amount. For example, as shown in FIG. 7, fine powder is used. It is information related to the fuel flow rate of the pulverized coal fuel when the co-firing rate of the charcoal fuel and the BFG fuel is 50% and the damper opening command value (first control command value) for adjusting the secondary air supply amount, for example. , Expressed by the Fx function. Further, in the basic information, an Fx function in which the fuel flow rate and the damper opening command value for adjusting the secondary air supply amount are associated with each other is set for the BFG fuel. For example, in one basic information, the damper opening command value for the pulverized coal-fired burner 20 and the damper opening command value for the BFG-fired burner 24 are set as a pair. Since the boiler 10 in the present embodiment has a plurality of dampers 40, a damper opening degree command value may be set for each damper in each operating situation.

The control command value for adjusting the secondary air supply amount is not limited to the damper opening command value, and the operation amount related to the mechanism capable of adjusting the primary air and the secondary air supply amount supplied to the boiler 10 is used. It can be used as appropriate. Further, the control command value for the factor affecting NOx and the unburned fuel content is, for example, in place of or in addition to the damper opening command value, at least one of the pulverized coal-fired burner 20 and the BFG-fired burner 24. A burner angle command value (second control command value) or the like for operating the burner angle α of the above may be used.
In addition, the factors that affect NOx and the amount of unburned fuel are not limited to the fuel flow rate of the pulverized coal fuel and the fuel flow rate of the BFG fuel, and for example, a boiler load may be used.

In the storage unit 51, a plurality of correction information is provided for each operating condition of the boiler as in the above basic information. For example, as shown in FIG. 6, a total of nine correction information Fx2-1 to Fx2_9 are created and stored in advance for each operating number of crushers (1 to 3) and for each coal type (A to C). It is stored in the unit 51.
The correction information Fx2-1 to Fx2_9 is information in which the coal co-firing rate and the correction value of the control command value regarding the secondary air supply amount are associated with each other in the combination of the plurality of fuels supplied to the boiler 10. For example, the above-mentioned basic information is a damper opening command for adjusting the fuel flow rate and the secondary air supply amount when the coal co-firing rate when burning pulverized coal fuel and BFG fuel is set to a reference value (for example, 50%). Although the relationship with the value is specified, if the coal co-firing rate changes from the standard value, for example, if the coal co-firing rate takes a value different from 50%, NOx and unburned content contained in the exhaust gas of the boiler 10 The amount of will change. The correction information is information that regulates the correction value of the air adjustment amount to compensate for such changes in the coal co-firing rate and to suppress NOx and unburned components to below the environmental regulation value even if the coal co-firing rate changes. be. For example, as shown in FIG. 8, the correction information is information in which the coal co-firing rate and the damper opening degree correction value for adjusting the secondary air supply amount are associated with each other. Further, when the burner angle α is controlled in place of or in addition to the secondary air supply amount, the correction information in which the coal co-firing rate and the burner angle correction value are associated with each other is used as the correction information.

The above-mentioned basic information and correction information for each operating condition are, for example, based on a large number of actual data obtained in the operating test by performing an operating test related to fuel adjustment on a boiler manufactured based on the same design information. It may be the created information, or it may be the information created based on the past operation data of a plurality of boilers manufactured based on the same design information. Further, the created plurality of basic information may be stored in the storage unit 51 at the time of manufacture, or may be stored in the storage unit 51 by downloading from a predetermined server after the product is delivered.

The basic information extraction unit 52 extracts basic information corresponding to the current operating status of the boiler from a plurality of basic information stored in the storage unit 51. For example, when the number of crushers currently in operation is two and the coal type is A, Fx1_4 is extracted (see FIG. 6).
If the current operating condition of the boiler is different from the mixed combustion rate based on the plurality of basic information stored in the storage unit 51, the correction information extraction unit 53 may perform a plurality of corrections stored in the storage unit 51. The correction information according to the current operating condition of the boiler is extracted from the information. For example, when the coal co-firing rate in the current operating condition of the boiler is different from the reference value (for example, 50%), the correction information extraction unit 53 extracts the correction information according to the current operating condition. For example, when the number of crushers currently in operation is two and the coal type is A, Fx2_4 is extracted.

The determination unit 54 uses the basic information extracted by the basic information extraction unit 52 to acquire the control command value of the air supply amount (particularly the secondary air supply amount), and the correction unit 54 extracts the correction information. Using the information, obtain the correction value corresponding to the current co-firing rate of each of multiple types of fuels. Then, the control command value obtained from the basic information is corrected by using the acquired correction value.
For example, the determination unit 54 uses the basic information extracted by the basic information extraction unit 52 to acquire the damper opening command value corresponding to each current fuel flow rate, and the correction unit 54 acquires the correction information extraction unit 53. Using the information, for example, the damper opening correction value corresponding to the current coal co-firing rate is acquired. Then, the damper opening command value obtained from the basic information is corrected by using each damper opening correction value obtained from the correction information, and the final damper opening command value is determined. When the damper opening command value is determined in this way, the opening degree of each damper 40 of the boiler 10 is controlled based on the determined damper opening command value. Further, when the burner angle α is controlled in place of or in addition to the secondary air supply amount, similarly, the burner angle command value obtained from the basic information is used as the burner angle correction value obtained from the correction information. To correct and determine the final burner angle command value.

Next, the procedure of the process executed by the control device 50 will be described with reference to FIG. FIG. 9 is a flowchart showing a processing procedure executed by the control device 50. In the flowchart shown in FIG. 9, an example is shown in which the amount of air supplied to the boiler, specifically, the amount of secondary air supply is controlled, but the same flow is used when controlling the burner angle. The final burner angle command value may be determined.

First, the control device 50 acquires information on the current operating status of the boiler 10 (SA1). For example, as an example, the current number of crushers in operation, coal type, number of burners in operation, boiler load, and coal co-firing rate when burning pulverized coal fuel and BFG fuel as reference values are acquired.
Subsequently, it is determined whether or not the current operating condition has changed from the previous operating condition (SA2). As a result, if the operating condition has changed from the previous time, for example, if at least one of the number of crushers in operation, the type of coal, the number of burners in operation, and the load of the boiler has changed (SA2: YES), in step SA1. Basic information corresponding to the acquired current operating condition is extracted from the storage unit 51 (SA3), and correction information is obtained when the reference value such as the coal co-firing rate when burning the pulverized coal fuel and the BFG fuel changes. Is extracted from the storage unit 51 (SA4).
Subsequently, the damper opening command value corresponding to the current fuel flow rate is acquired from the basic information acquired in step SA3 (SA5), and the damper opening correction corresponding to the current coal co-firing rate is obtained from the correction information acquired in step SA4. Get the value (SA6).
Then, the damper opening command value acquired in step SA5 is corrected by the damper opening correction value acquired in step SA6, and the final damper opening command value is calculated (SA7). When the final damper opening command value is calculated in this way, the opening degree of each damper 40 is controlled based on the damper opening command value (SA8), and the process returns to step SA1.

On the other hand, when the control device 50 determines in step SA2 that the operating condition of the boiler 10 has not changed, the control device 50 returns to step SA1 without changing the current damper opening degree (SA9), and returns to step SA1 as described above. Repeat the process.

As described above, according to the boiler control device and the boiler control method according to the present embodiment, at least one of a combination of a plurality of types of fuel to be supplied to the boiler, the number of crushers in operation, and the number of burners in operation can be determined. Prepare multiple basic information (set by Fx function) prepared for each boiler operating status including, and acquire the basic information corresponding to the current boiler operating status from these basic information, and acquire the basic information. At least one of a control command value (for example, a damper opening command value) regarding an air supply amount (particularly a secondary air supply amount) and a control command value (for example, a burner angle command value) regarding a gas ejection angle based on the information. To decide. This makes it possible to finely and appropriately control the amount of air supplied to the boiler, the burner angle α, and the like according to the operating conditions of the boiler. As a result, NOx and unburned fuel contained in the exhaust gas discharged from the boiler can be more reliably set within the environmental regulation values.

Further, according to the present embodiment, correction information in which the co-firing rate of each fuel used as a reference when creating the reference information and the correction value of the control command value are associated with each other is prepared for each operating condition of the boiler. , The correction value is acquired using the correction information according to the current boiler operating condition, and the control command value (for example, damper opening command value or burner angle command value) determined from the basic information based on the acquired correction value is used. to correct. As a result, it is possible to obtain at least one of an appropriate air supply amount and burner angle α not only in the operating condition of the boiler but also in the co-firing rate of each of a plurality of types of fuels. This makes it possible to more reliably keep NOx and unburned fuel content below the environmental specified values.

Although the present invention has been described above using the embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments. Various changes or improvements can be made to the above embodiments without departing from the gist of the invention, and the modified or improved embodiments are also included in the technical scope of the present invention. Moreover, you may combine the said embodiment as appropriate.
Further, the flow of processing executed by the control device 50 described in the above embodiment is also an example, and unnecessary steps are deleted, new steps are added, and processing is performed within a range that does not deviate from the gist of the present invention. You may change the order.

For example, in the above embodiment, the basic information Fx1-1 to Fx1_9 and the correction information Fx2-1 to Fx2_9 are prepared in advance, but the correction information Fx2-1 to Fx2_9 is appropriately updated by using the test run data and the actual operation data of the boiler 10. It may be done (update means).
For example, when the air supply amount (particularly the secondary air supply amount) is controlled based on the basic information and the correction information stored in the storage unit 51, NOx and the unburned fuel content exceed the environmental regulation value. If this happens, work (control) is performed to adjust the air supply amount and / or the burner angle α according to the actual NOx emissions and the unburned fuel content. Then, by updating the characteristics of the correction information based on such test run data and actual operation data, the correction information can be customized according to the characteristics of the actual machine. This improves the control accuracy of the air supply amount and / or the burner angle α, and makes it possible to more reliably suppress NOx and unburned fuel content within the environmental regulation values.

Further, in the above embodiment, the case where a plurality of basic information and correction information are stored in the storage unit 51 has been described as an example, but it is not always necessary to include the storage unit 51. For example, a plurality of basic information and correction information are stored on a predetermined server (on the cloud), and the basic information extraction unit 52 and the correction information extraction unit 53 access the server as needed to operate the current boiler. It may be a mode to acquire the basic information and the correction information according to the situation.

10: Boiler 11: Fire furnace 21: Fuel burner 27: Crusher 40: Damper 50: Control device 51: Storage unit 52: Basic information extraction unit 53: Correction information extraction unit 54: Determination unit

Claims (6)

Controls applied to boilers that are equipped with multiple crushers and multiple burners for burning the fuel and can co-fire multiple types of fuel, including pulverized fuel produced by crushing solid fuel with the crusher. It ’s a device,
A storage means for storing a plurality of basic information in which control command values for burning the plurality of types of fuel are set for each operating condition of the boiler, and a storage means.
A basic information extraction means for extracting the basic information corresponding to the current operating condition of the boiler from the storage means, and
A determination means for determining the control command value using the extracted basic information is provided.
The operating condition of the boiler includes at least one of the combination of the plurality of types of fuel supplied to the boiler, the number of operating units of the crusher, and the operating number of the burner.
The control command value is a boiler including at least one of a first control command value relating to an amount of air supplied to the boiler and a second control command value relating to a horizontal ejection angle of gas ejected from the burner into the boiler. Control device. The boiler control device according to claim 1, wherein the operating condition of the boiler further includes at least one of a load which is a steam generation ratio with respect to a rated steam generation amount of the boiler and a type of fuel supplied to the boiler. The storage means stores a plurality of correction information in which the co-firing rate of each fuel in the combination of the plurality of types of fuel supplied to the boiler and the correction value of the control command value are associated with each operation status. Being done
A correction information extraction means for extracting the correction information corresponding to the current operating condition of the boiler from the storage means is provided.
The determination means acquires a correction value corresponding to the current co-firing rate of the plurality of types of fuels using the extracted correction information, and uses the acquired correction value to determine using the basic information. The boiler control device according to claim 1 or 2, wherein the control command value is corrected. The boiler control device according to claim 3, further comprising an updating means for updating the correction information based on actual operation data. With the plurality of crushers,
With the multiple burners,
A boiler including the control device for the boiler according to any one of claims 1 to 4. Controls applied to boilers that are equipped with multiple crushers and multiple burners for burning the fuel and can co-fire multiple types of fuel, including pulverized fuel produced by crushing solid fuel with the crusher. It ’s a method,
A step of extracting the basic information corresponding to the current operating condition of the boiler from a plurality of basic information in which control command values for burning the plurality of types of fuel are set for each operating condition of the boiler. ,
It has a step of determining the control command value using the extracted basic information.
The operating condition of the boiler includes at least one of the combination of the plurality of types of fuel supplied to the boiler, the number of operating units of the crusher, and the operating number of the burner.
The control command value is a boiler including at least one of a first control command value relating to an amount of air supplied to the boiler and a second control command value relating to a horizontal ejection angle of gas ejected from the burner into the boiler. Control method.

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