JP7524629B2 - Coal and Biomass Operation Support System - Google Patents

Description

The present invention relates to a coal and biomass operation support system.

In recent years, due to rising fuel prices and tight demand, coal-fired power plants are increasingly using not only high-grade coal such as bituminous coal, but also low-grade coal such as sub-bituminous coal. In addition, a method of using a mixture of multiple coal types (coal blending) or coal and biomass fuel (coal blending) as fuel has also been widely adopted.

On the other hand, coal-fired power plants and other smoke-producing facilities, in accordance with the Air Pollution Control Act, submit smoke-related information (hereinafter sometimes referred to as "information") to public institutions, which includes information on the component values of the fuel used, the amount of exhaust gas, and the concentration of exhaust gas. In addition, the fuel analysis values and other information listed in the information are used as standards to determine whether or not coal can be used as fuel.

For example, when multiple types of coal are blended and used as fuel for a coal-fired power plant, the component values of the blended coal are calculated, and a judgment is made as to whether the coal can be used by determining whether the calculated values meet the standards for fuel analysis values and other criteria described in the instructions (see, for example, Patent Document 1).

JP 2007-115203 A

However, the fuel analysis values listed in the instructions are merely the component values of representative grade coal, and merely indicate that the theoretical values of exhaust gas components and exhaust gas volumes calculated from the component values meet the standards set out in the Air Pollution Control Act and other laws. Therefore, it is not necessarily reasonable to judge whether or not a coal can be used simply based on the fact that the component values of a single type or blended coal, or a fuel made by mixing such coal with biomass fuel (hereinafter sometimes referred to as "coal, etc. fuel") meet the standards of the fuel analysis values, etc. listed in the instructions.

In other words, even if a coal or other fuel meets the standards (reported values) for fuel analysis values, etc., listed in the instruction manual, it is possible that it does not meet the legal standards set out in the Air Pollution Control Act, etc., and even if a coal or other fuel does not meet the reported values, it may still meet the legal standards. However, in a situation where there were no other standards, there was no choice but to determine whether or not coal or other fuels could be used according to the reported values. Therefore, it was irrational to uniformly determine that any coal or other fuel that did not meet the reported values could not be used, and even for coal or other fuels that were determined to be usable, whether or not the actual exhaust gas components and exhaust gas volume met the legal standards was monitored and confirmed during operation.

The present invention was made in consideration of the above problems, and aims to provide a coal and biomass operation support system that can reliably comply with statutory standards such as the Air Pollution Control Act and supports rational operation of coal and other fuels.

(1) A coal and biomass operation support system comprising: a reception unit that receives input of property item values and blending ratios of one or more types of coal or biomass fuel; a storage unit that stores the property item values and blending ratios of the one or more types of coal or biomass fuel; an exhaust gas component concentration calculation unit that calculates a first exhaust gas component concentration prediction value from the property item values and blending ratios of the one or more types of coal or biomass fuel; a fuel consumption calculation unit that calculates a maximum prediction value of fuel consumption at which both a second exhaust gas component concentration and an exhaust gas amount are within a predetermined threshold value from the property item values and blending ratios of the one or more types of coal or biomass fuel; and an output unit that outputs the first exhaust gas component concentration prediction value and the maximum prediction value of fuel consumption.

(2) It is preferable that the coal and biomass operation support system includes a means for acquiring a measurement value of the first exhaust gas component concentration and a means for acquiring a measurement value of the fuel consumption amount.

(3) The coal and biomass operation support system preferably includes a first determination unit that determines whether the first exhaust gas component concentration prediction value is within a predetermined threshold value, and a second determination unit that determines whether the maximum predicted value of the fuel consumption amount is equal to or greater than a predetermined threshold value, and the output unit preferably outputs the determination results of the first determination unit and the second determination unit.

(4) It is preferable that the first exhaust gas component includes nitrogen oxides, and the second exhaust gas component includes soot and dust.

(5) The property item values preferably include carbon, hydrogen, oxygen, total sulfur, total moisture, nitrogen, ash, and inherent moisture.

(6) A coal and biomass operation method using the coal and biomass operation support system described in any one of (1) to (5) above, comprising: a step of selecting the type or variety of the one or more types of coal, or the biomass fuel, and a blending ratio; and a step of determining whether or not the one or more types of coal, or the blended coal, or the fuel obtained by mixing the coal and the biomass fuel, can be used by comparing the first exhaust gas component concentration prediction value and the maximum predicted value of the fuel consumption amount with respective predetermined thresholds.

(7) A coal and biomass operation method using the coal and biomass operation support system described in any one of (2) to (5) above, which includes a monitoring step of comparing the measured value of the first exhaust gas component concentration, the measured value of the second exhaust gas component concentration, and the measured value of the fuel consumption with respective predetermined thresholds, and revising the calculation method of the predicted value of the first exhaust gas component concentration or the calculation method of the maximum predicted value of the fuel consumption based on the results of the monitoring step.

(8) A coal and biomass operation support program comprising: an input receiving function for inputting property item values and blending ratios of one or more types of coal or biomass fuel; an exhaust gas component concentration calculation function for calculating a first exhaust gas component concentration prediction value from the property item values and blending ratios of the one or more types of coal or biomass fuel; a fuel consumption calculation function for calculating a maximum predicted value of fuel consumption at which both a second exhaust gas component concentration and an exhaust gas amount are within a predetermined threshold from the property item values and blending ratios of the one or more types of coal or biomass fuel; a first judgment function for judging whether the first exhaust gas component concentration prediction value is within a predetermined threshold; a second judgment function for judging whether the maximum predicted value of fuel consumption is equal to or greater than a predetermined threshold; and an output function for the judgment results obtained by the first judgment function and the second judgment function.

This invention makes it possible to reliably comply with legal standards set forth in the Air Pollution Control Act and other laws, while also enabling rational use of coal and other fuels.

1 is a block diagram showing a schematic configuration of a coal and biomass operation support system 1 according to an embodiment of the present invention. 1 is a flowchart showing a process flow of a coal and biomass operation support program in one embodiment of the present invention. 1 is a flowchart showing a flow of a coal and biomass operation method in one embodiment of the present invention. 1 is a flowchart showing a flow of a coal and biomass operation method in one embodiment of the present invention.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
<Outline of coal and biomass operation support system>
1 is a block diagram showing a schematic configuration of a coal and biomass operation support system 1 according to an embodiment of the present invention. Such a coal and biomass operation support system 1 is preferably used in, for example, a coal-fired power plant equipped with a pulverized coal boiler.

The coal and biomass operation support system 1 includes a management terminal 2. The management terminal 2 includes a central processing unit 3, a reception unit 21, a memory unit 22, an output unit 23, and an I/F unit 24 that is connected to an external device so as to be able to communicate wirelessly or via wires.

The management terminal 2 is a computer device equipped with a CPU, memory, etc. (not shown), and is a device that can be connected to a network or external devices via the I/F unit 24. The management terminal 2 is used when determining whether or not fuels such as coal can be used as fuel in coal-fired power generation facilities, etc. Alternatively, it is used when displaying exhaust gas concentration measurement values and fuel consumption measurement values obtained from external devices to monitor the operating status of the power generation facility.

The reception unit 21 receives input of the property item values and blending ratio of the coal or biomass fuel selected by the user (in this specification, "blend ratio" means the ratio of each coal when two or more types of coal are blended, and means the ratio of each coal and biomass fuel when one or more types of coal and biomass fuel are blended), or receives corrections made by the user to the calculation formula for exhaust gas concentration and fuel consumption based on the property item values and blending ratio of the coal or biomass fuel, and instructs the management terminal 2. The reception unit 21 receives user input from an input device such as a keyboard, mouse, or touch panel.

The memory unit 22 is a storage device such as a hard disk. The memory unit 22 stores property item values and blending ratios of coal or biomass fuel input by the user, calculation formulas for exhaust gas concentration and fuel consumption, calculation programs and various thresholds for predicted values of exhaust gas concentration and fuel consumption, and a program for determining whether coal can be used based on the various thresholds.

The output unit 23 outputs the input property item values and blending ratio of the coal or biomass fuel, the calculation results of the predicted and measured values of the exhaust gas concentration and fuel consumption, the judgment result of the usability of the coal or biomass fuel by the judgment program, etc. The output unit 23 displays various information, images, etc. via a display device such as a display.

The I/F unit 24 is an interface to which external devices can be connected. Examples of external devices connected to the I/F unit 24 include an exhaust gas concentration meter 41 and a coal feeder 42. In addition to the above, the I/F unit 24 may be connected to a database server in which property item values and storage amounts of various coals or biomass fuels are stored.
Therefore, the management terminal 2 can acquire the measurement values of the exhaust gas concentration meter 41 and the coal feeder 42 through the I/F unit 24 .

The exhaust gas concentration meter 41 is provided in the flow path of exhaust gas generated by a pulverized coal boiler or the like, and has a communication function to measure the concentration of exhaust gas components such as nitrogen oxides (hereinafter sometimes referred to as NOx), soot, sulfur oxides (hereinafter sometimes referred to as SOx), etc., and transmits the measurement results to the management terminal 2.
The installation position of the exhaust gas concentration meter 41 varies depending on the measurement target. The exhaust gas concentration meter 41 that measures NOx is provided, for example, on the outlet side of a denitrification facility that purifies NOx with a catalyst. The dust concentration meter that measures dust is provided, for example, on the outlet side of an electric dust collector that removes dust. The exhaust gas concentration meter 41 that measures SOx is provided, for example, on the outlet side of a desulfurization facility that purifies SOx with a catalyst.

The coal feeder 42 is a device that supplies coal or biomass fuel to a pulverized coal boiler or the like, and is provided upstream of a number of mills that pulverize the coal or biomass fuel, corresponding to the mills. The coal feeder 42 has a conveyor that transports the coal or biomass fuel and a load cell that detects the load of the coal or biomass fuel, and can detect the conveyor speed and load. From these detection results, the coal feeder 42 can measure the supply amount of coal or biomass fuel as fuel consumption, and has a communication function that transmits the measurement results to the management terminal 2.

The central processing unit 3 executes various programs stored in the memory unit 22. These programs are composed of an exhaust gas component concentration calculation unit 31, a fuel consumption calculation unit 32, a first judgment unit 33, and a second judgment unit 34.

The exhaust gas component concentration calculation unit 31 calculates the exhaust gas component concentration when coal or other fuel is burned as fuel based on the property item values and blending ratio of coal or biomass fuel input by the user. For example, it calculates a predicted value of the component concentration (ppm) in the exhaust gas of NOx as the first exhaust gas component. Note that the first exhaust gas component may also include other substances for which legal emission standards (concentrations) are set by law, such as SOx.

The fuel consumption calculation unit 32 calculates the maximum predicted value of fuel consumption (t/h) at which the second exhaust gas component, for example, the soot concentration and exhaust gas volume, are within a predetermined threshold value when coal or other fuel is burned as fuel, based on the property item values and blending ratio of coal or biomass fuel input by the user. In other words, when the actual fuel consumption is within the maximum predicted value of the calculated fuel consumption, it is expected that the second exhaust gas component concentration and exhaust gas volume will be within the predetermined threshold value.

The first determination unit 33 determines whether the predicted value of the concentration (ppm) of the first exhaust gas component, for example NOx, in the exhaust gas calculated by the exhaust gas component concentration calculation unit 31 is within a predetermined threshold value.

The second determination unit 34 determines whether the maximum predicted value of fuel consumption (t/h) calculated by the fuel consumption calculation unit 32 is equal to or greater than a predetermined threshold value.

Next, a method for calculating the predicted values performed by each of the calculation units 31 and 32 will be described.
[Calculation of NOx concentration in exhaust gas (exhaust gas component concentration calculation unit 31)]
The predicted value of the NOx concentration in the exhaust gas (NOx concentration at the denitration inlet) as the first exhaust gas component can be calculated by the following calculation formula.
(Equation 1)
NOx concentration in exhaust gas = 19.3 x fuel ratio x (1 + fuel nitrogen content (%, CH base)) + 97 (ppm)
(In the above formula, "CH basis" indicates the analysis value at a constant humidity of 75%. The fuel ratio is calculated from the ratio of fixed carbon to volatile matter.)

According to the above formula (1), even if the fuel nitrogen content is relatively high, if the fuel ratio is relatively low, the predicted NOx value may remain relatively unchanged or may be calculated to be low.

[Calculation of exhaust gas amount (fuel consumption calculation unit 32)]
The amount of exhaust gas (amount of gas at the exhaust port) (wet, dry) can be calculated using the following formula using the property item values of coal or biomass fuel: carbon (C), hydrogen (H), oxygen (O), total sulfur (S), total moisture (W1), and nitrogen (N).
(Equation 2)
Theoretical air volume ((A0)) = 8.89C + 26.7 x (HO/8) + 3.33S
Theoretical combustion gas amount (Q0) = 1.867C + 0.7S + 11.2H + 1.24W1 + 0.8N + 0.79A0
Actual combustion gas volume (wet) (Q') = Q0 + (1.31-1) x A0
Actual combustion gas volume (dry) (Q") = Q' - (11.2H + 1.24W1)
Desulfurization equipment inlet water vapor amount (Qs) = (Q' x fuel consumption x 1000) - (Q” x fuel consumption x 1000)
Amount of steam at the outlet of the desulfurization device (Qc) = (Q' x fuel consumption x 1000 x 1.3 - Qs/1.244) x 0.077 x 1.244
Amount of gas generated by the denitrification device (Qa) = Qc - Qs + 10000
Exhaust gas volume (wet) = Q' x fuel consumption x 1000 + Qa
Exhaust gas volume (dry) = (Q" x fuel consumption x 1000) + 10000

The above formula (2) can be used to calculate the maximum predicted value (p1) of fuel consumption when both exhaust gas amounts (wet, dry) are within a predetermined threshold value. In other words, the smaller of the fuel consumption amounts calculated when the exhaust gas amounts (wet, dry) in the above formula (2) are set to the respective predetermined threshold values can be calculated as the above maximum predicted value (p1). Note that the above predetermined threshold values are determined according to statutory emission standards.

[Calculation of dust concentration in exhaust gas (fuel consumption calculation unit 32)]
The dust concentration in the exhaust gas (dust concentration at the dust collector inlet) can be calculated using the above-mentioned coal or biomass fuel property item values, as well as ash content (A) and specific moisture (W2), according to the following formula.
(Equation 3)
Dust concentration in exhaust gas = A x ((fuel consumption - (fuel consumption x (W1 - W2)) x 1000/Q" x 1000)

According to the above formula (3), the dust concentration in the exhaust gas is correlated with the fuel consumption amount as well as with the ash content.
Furthermore, the maximum predicted value (p2) of the fuel consumption amount at which the particulate matter concentration in the exhaust gas falls within a predetermined threshold value can be calculated from the above (Equation 3). That is, the maximum predicted value (p2) can be calculated as the fuel consumption amount when the particulate matter concentration in the exhaust gas in the above (Equation 3) is set to a predetermined threshold value. The predetermined threshold value is determined according to the statutory emission standard.

The smaller of the maximum predicted values (p1) and (p2) of fuel consumption calculated by the above (Equation 2) and (Equation 3) can be calculated as the maximum predicted value (p3) of fuel consumption at which the soot concentration as the second exhaust gas component and the exhaust gas volume are within a predetermined threshold value.

[First judgment section, second judgment section]
(Threshold)
Next, the threshold values used for the judgment in the first judgment section and the second judgment section and the evaluation corresponding to the threshold values will be described.

Table 1 shows an example of threshold values conventionally used to determine whether or not fuels such as coal can be used, and the evaluation results corresponding to the threshold values.
The thresholds a1 and a2 are determined based on the fuel analysis values (hereinafter, sometimes referred to as "reported values") described in the instruction manual. As shown in Table 1, for example, when the index X1 indicating the property item value of the ash content of a fuel such as coal exceeds the threshold value a1, the evaluation is marked as "X." The same is true for the index X2 indicating the property item value of the nitrogen content. In addition, when any of these indicators is evaluated as "X," the fuel such as coal is determined to be unusable.

Table 2 shows an example of thresholds used to determine whether or not fuel such as coal can be used in one embodiment of the present invention, and evaluation results corresponding to the thresholds.
The index X1 indicates the property item value of ash. As shown in Table 2, a new operational limit value b1 is set as a threshold value for the index X1, and when the index X1 is equal to or less than the threshold value a1, it is evaluated as ◯, when the index X1 is greater than the threshold value a1 to b1, it is evaluated as ▲, and when the index X1 exceeds the threshold value b1, it is evaluated as ×. The evaluation ▲ indicates that the notified value is exceeded, but operation is possible depending on other evaluation items. This is because the property item value of ash correlates with the dust concentration, but the dust concentration also correlates with the fuel consumption, so that depending on the fuel consumption, even if the ash exceeds the threshold value a1, operation may be possible while complying with the legal standard for the dust concentration.

The indicator X2 indicates the property item value of the nitrogen content. Similarly, for the indicator X2, a new operational limit value b2 is set as a threshold value, and if the threshold value a2 is exceeded but is within the operational limit value b2, the evaluation is similarly marked as ▲. This is because the NOx concentration prediction value correlates with the nitrogen content, but also correlates with the fuel ratio, so that even if the nitrogen content exceeds the threshold value a2, it may be possible to operate the vehicle while complying with the legal standard for the NOx concentration.
The operational limit values b1 and b2 are set as values that make operation impossible even when other correlation values are taken into consideration, for example.

The indicator X3 indicates the denitration inlet NOx concentration. As the indicator X3, a predicted value of the NOx concentration in the exhaust gas as the first exhaust gas component, calculated by the exhaust gas component concentration calculation unit 31, is used. As shown in Table 2, when the indicator X3 is equal to or less than the threshold value a3, it is evaluated as ◯, when it is greater than the threshold value a3 to b3, it is evaluated as △, and when it exceeds the threshold value b3, it is evaluated as ×. The threshold value b3 is set according to a statutory standard defined by laws and regulations.
The evaluation △ indicates that the theoretical value of the index X3 does not exceed the legal standard, and the fuel such as coal is operable, but caution is required in monitoring. In other words, the threshold value a3 is set as a value having a considerable margin of error with respect to the legal standard.

The index Y indicates the coal or other fuel consumption amount complying with the exhaust gas amount. As the index Y, the maximum predicted value of the fuel consumption amount (p3) calculated by the fuel consumption amount calculation unit 32 is used. As shown in Table 2, when the index Y is equal to or greater than the threshold value a4, the evaluation is made as ◎, when the index Y is less than the threshold value a4 to b4, the evaluation is made as ◯, and when the index Y is less than the threshold value b4, the evaluation is made as ▲.
Conventionally, the threshold value for fuel consumption has been the numerical value (A4) stated in the instruction manual. However, since fuel consumption correlates with exhaust gas volume and dust concentration, it is preferable to set a threshold value taking into account the statutory standards for exhaust gas volume and dust concentration.

Therefore, in this embodiment, the suitability of coal use is determined based on whether the maximum predicted value of fuel consumption (p3) is equal to or greater than a threshold value b4 set as an upper limit guideline value of actual fuel consumption, which makes it possible to more reliably comply with statutory standards for exhaust gas volume and particulate matter concentration, and to rationally operate coal and other fuels.
As shown in Table 2, even if the index Y is less than b4, the evaluation is ▲ and it is considered to be operable under other conditions. This is because, depending on the operating conditions of the pulverized coal boiler and the calorific value of the fuel such as coal, the actual fuel consumption may be lower than b4, and operation may be possible even if the index Y is less than b4.

(Determination in the First Determination Unit and the Second Determination Unit)
According to the thresholds and evaluations in Table 2, if the index X3 of the denitration inlet NOx concentration as the first exhaust gas component is within the threshold b3, the first judgment unit judges that the coal or other fuel can be operated depending on the judgment result of the second judgment unit, and if the index X3 exceeds the threshold b3, it judges that the coal or other fuel cannot be operated.
Similarly, if the index Y of coal consumption in compliance with exhaust gas volume, as the maximum predicted value of fuel consumption, is equal to or greater than threshold value b4, the second judgment unit judges that the coal or other fuel can be operated depending on the result of the first judgment unit, and if it is less than threshold value b4, it judges that other conditions, such as operating conditions, need to be checked before operation.

Next, we will explain a specific example in which the calculation of predicted values of the above exhaust gas components and judgments based on thresholds are applied to actual operations using fuels such as coal.

<Coal and Biomass Operational Support Program>
Fig. 2 is a flowchart showing the flow of processing of a coal and biomass operation support program executed by the central processing unit 3 in one embodiment of the present invention. The coal and biomass operation support program shown in Fig. 2 is used when determining whether or not fuel such as coal can be used as fuel in a pulverized coal boiler or the like.

As shown in FIG. 2, the central processing unit 3 receives input of property item values and coal type or variety and coal blending ratio of coal or biomass fuel via the receiving unit 21 (S1, S2).
Next, the central processing unit 3 calculates a predicted value X3 of the denitration inlet NOx concentration as the first exhaust gas component concentration using the input values and (Equation 1) (S3). When multiple coal types or varieties are input, the central processing unit 3 calculates the property item values of the coal or other fuel after blending from the blending ratio, and then performs the process of S3.
Next, the central processing unit 3 calculates the fuel consumption Y as the maximum predicted value (p3) of fuel consumption at which the soot concentration as the second exhaust gas component and the exhaust gas amount are both within predetermined threshold values using the input values and (Equation 2) and (Equation 3) (S4).

Next, the central processing unit 3 compares the concentration X3 calculated in S3 with a predetermined threshold b3 and judges whether the concentration X3 is within the threshold b3 (S5). The predetermined threshold b3 is set according to a legal standard stipulated by laws and regulations.
If the concentration X3 exceeds the threshold b3, the central processing unit 3 determines that the fuel such as coal is not suitable for use. Specifically, a list of evaluation items as shown in Table 2 is displayed, and the evaluation result is displayed and colored in the column showing the denitration inlet concentration X3, and a message indicating that the fuel is not suitable for use as a comprehensive evaluation is output via the output unit 23. If the concentration X3 is within the threshold b3, the central processing unit 3 executes the next step S6.

Next, the central processing unit 3 compares the fuel consumption amount Y calculated in S4 with a predetermined threshold b4 to determine whether the fuel consumption amount Y is equal to or greater than the threshold b4 (S6). The predetermined threshold b4 is set as an upper limit guideline value for the actual fuel consumption amount.
When the fuel consumption amount Y is equal to or greater than the threshold value b4, the central processing unit 3 determines that the fuel such as coal is operable. When the fuel consumption amount Y is less than the threshold value b4, the central processing unit 3 determines that the operation of the fuel such as coal requires confirmation. The specific method of outputting the determination result in S6 is the same as in S5.

Next, we will explain a coal and biomass management method using the coal and biomass management support system 1 in one embodiment of the present invention.

<Coal and biomass operation method (coal type or variety and blending ratio determination)>
3 is a flowchart showing the flow of a coal and biomass operation method using the coal and biomass operation support system 1 and the above program. This operation method is used when determining the coal type or variety and blending ratio of coal or biomass fuel to be used as fuel in a pulverized coal boiler or the like.

First, the user analyzes the properties of various coals or biomass fuels, and inputs the coal type or variety and property item values into the management terminal 2 (S7). Note that the property item values analyzed in advance may be separately acquired from a database server or the like, and the above input may be performed.
Next, in a selection step S8, the user selects candidate coal types or varieties and coal blend ratios from the coal types or varieties input in S7, and inputs them to the management terminal 2.

Next, the user instructs the management terminal 2 to execute the above program. The management terminal 2 calculates the exhaust gas component concentration prediction value X3 and the fuel consumption prediction value Y (S9, S10), compares them with the respective threshold values b3 and b4 to make a judgment (S11, S12), and outputs the judgment result.

Next, if a determination result indicating that operation is not possible is output in S11 above, that is, if the predicted value X3 exceeds b3, the user returns to S8 and reselects the coal type or variety and blending ratio of coal or biomass fuel.
If the determination result indicates that confirmation is required in S12, that is, if the predicted value Y is less than b4, the user determines whether operation is possible in consideration of the boiler operating status and the heat value of the coal or biomass fuel in decision step S13. If the user determines that operation is not possible in S13, the process returns to S8 and reselects the type or variety of coal or biomass fuel and the blending ratio.

If the determination result in S12 above indicates that operation is possible, or if the determination in S13 above indicates that operation is possible, the user determines the coal type or variety and coal blend ratio based on the selection made in S8.

<Coal and biomass operation methods (combustion monitoring and review of standards)>
Next, a coal and biomass management method using the coal and biomass management support system 1 according to one embodiment of the present invention will be described.
4 is a flowchart showing the flow of a coal and biomass operation method in one embodiment of the present invention using the coal and biomass operation support system 1. This operation method is used to monitor exhaust gas components and exhaust gas volume when a pulverized coal boiler or the like is operated using coal or other fuel whose coal type or type and blending ratio have been determined. This operation method is also used to review calculation formulas and judgment criteria based on the monitoring results.

In accordance with the user's instructions, the management terminal 2 acquires, via the exhaust gas concentration meter 41, a measured value X3' of the NOx concentration at the outlet side of the denitrification equipment as the first exhaust gas concentration, and a measured value X5' of the soot and dust concentration as the second exhaust gas concentration (S14). Similarly, the management terminal 2 acquires a measured value Y' of the fuel consumption amount via the coal feeder 42 (S15).

Next, the central processing unit 3 in the management terminal 2 executes a monitoring step S16 in which the measured values X3', X5' are compared with the predetermined threshold values b3', b5' to determine whether the measured values X3', X5' are within the predetermined threshold values b3', b5', respectively. Note that the threshold values b3', b5' are legal standards set forth by laws and regulations.
If the result of S16 is that the measured values X3', X5' are both within the predetermined threshold values b3', b5' respectively, the management terminal 2 executes the next monitoring step (S17).

Next, the central processing unit 3 executes a monitoring step S17 in which the measured value Y' is compared with a predetermined threshold value b4' to determine whether the measured value Y' is within the predetermined threshold value b4'. Note that as the threshold value b4', a value set by taking into account the upper limit guide value of the actual fuel consumption amount and the driving conditions, etc. is used. After executing S16 and S17, the central processing unit 3 outputs the determination result via the output unit 23.
It is preferable that the above steps S14 to S17 are automatically repeated at regular intervals without waiting for a user's instruction each time.

If the results of the above monitoring steps S16 and S17 show that the measured values X3', X5', and Y' are all within the predetermined threshold values b3', b5', and b4', the user checks the judgment result output by the output unit 23 and continues operation of the pulverized coal boiler, etc.

If the result of S16 shows that either the measured value X3' or X5' exceeds the threshold value b3' or b5', or if the result of S17 shows that the measured value Y' exceeds the threshold value b4', the user determines whether or not it is possible to continue driving (S18).
The judgment as to whether or not the operation can be continued specifically refers to the following judgment.

When each of the above measured values exceeds each threshold value, the user performs control by the user's own operation or automatic control so that each measured value falls within each threshold value.
For example, when a measured value X3' of the NOx concentration on the outlet side of the denitration equipment exceeds a predetermined threshold value b3', the amount of ammonia injected into the denitration equipment is increased and the set value of the NOx concentration is reduced.
When the measured dust concentration value X5' exceeds a predetermined threshold value b5', the dust concentration is reduced by changing the charge control of the EP (electrostatic precipitator) or increasing the opening of the blades of the absorption tower circulation pump of the desulfurization device.
In addition, if the measured fuel consumption Y' exceeds a predetermined threshold value b4', the soot blower is stopped, the load change rate is reduced, and operations that increase fuel consumption, such as supplying coal slurry and switching the mill, are stopped to reduce fuel consumption.

However, if the measured values frequently exceed the thresholds even with the above control, the user determines that it is impossible to continue operation and changes the coal type or variety and the coal blending ratio (S19). For example, the program described in the above embodiment is used for the above changes.
In addition, the user reviews the calculation formulas for the exhaust gas component concentrations and the fuel consumption amount, or reviews the thresholds (evaluation) (S20). The reviews are performed, for example, by checking the fuel analysis values of the excess items, checking the heat generation amount, and comparing the calculated theoretical values with the measured values.

Then, steps S14 to S17 are executed again by the management terminal 2, and the above decision S18 or the continuation of operation is made based on the results.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments. For example, the coal and biomass operation support system 1 may be applied to coal combustion facilities other than power generation facilities equipped with pulverized coal boilers.

In addition, in the above embodiment, the central processing unit 3 is configured to have the first judgment unit 33 and the second judgment unit 34, but this is not limited to this, and for example, the comparison of the calculated exhaust gas component concentration and predicted fuel consumption amount with a threshold value may be performed by a human being.
Similarly, the monitoring steps 16 and 17 in which various measurements made during combustion monitoring are compared with threshold values may be performed by a person rather than by the management terminal 2 .

Furthermore, the threshold b4 of the fuel consumption Y may be variable, taking into account the calorific value of the coal or biomass fuel. For example, if the calculated fuel consumption Y falls below the threshold b4, the evaluation is ▲, but if the fuel consumption estimated from the calorific value of the coal or biomass fuel falls below the calculated value, the threshold b4 may be corrected according to the result and the evaluation may be changed to ◯.
Alternatively, when calculating the fuel consumption amount Y, the fuel consumption amount Y may be corrected by taking into account the calorific value of the coal or biomass fuel.

In addition, in the above embodiment, some of the various thresholds are described as using legal standards, but this is not limited to this, and values that have a certain margin of error relative to the legal standards may be used as the above thresholds.

REFERENCE SIGNS LIST 1 Coal and biomass operation support system 2 Management terminal 21 Reception unit 22 Memory unit 23 Output unit 24 I/F unit 3 Central processing unit 31 Exhaust gas component concentration calculation unit 32 Fuel consumption calculation unit 33 First judgment unit 34 Second judgment unit 41 Exhaust gas concentration meter 42 Coal feeder

Claims (6)

A reception unit that receives input of property item values and a coal blending ratio of one or more types of coal or biomass fuel;
A memory unit that stores property item values and coal blending ratios of the one or more types of coal or biomass fuel;
an exhaust gas component concentration calculation unit that calculates a first exhaust gas component concentration prediction value from property item values and a coal blending ratio of the one or more types of coal or biomass fuel;
A fuel consumption calculation unit that calculates a maximum predicted value of fuel consumption at which both the second exhaust gas component concentration and the exhaust gas amount are within a predetermined threshold value based on the property item values and the coal blending ratio of the one or more types of coal or biomass fuel;
an output unit that outputs the first exhaust gas component concentration predicted value and the maximum predicted value of the fuel consumption amount ,
The first exhaust gas component includes nitrogen oxides, and the second exhaust gas component includes soot and dust,
The property item values include carbon, hydrogen, oxygen, total sulfur, total moisture, nitrogen, ash and inherent moisture;
The exhaust gas component concentration calculation unit calculates the first exhaust gas component concentration prediction value by the following (Equation 1),
(Equation 1) NOx concentration in exhaust gas = 19.3 x fuel ratio x (1 + fuel nitrogen content (%, CH base)) + 97 (ppm)
(In the above formula 1, "CH base" indicates an analysis value at a constant humidity of 75%. The fuel ratio is calculated from the ratio of fixed carbon to volatile matter.)
The fuel consumption calculation unit calculates a maximum predicted value (p1) of fuel consumption by the following (Equation 2):
(Formula 2) Theoretical air amount ((A0)) = 8.89C + 26.7 × (HO / 8) + 3.33S
Theoretical combustion gas amount (Q0) = 1.867C + 0.7S + 11.2H + 1.24W1 + 0.8N + 0.79A0
Actual combustion gas volume (wet) (Q') = Q0 + (1.31-1) x A0
Actual combustion gas volume (dry) (Q") = Q' - (11.2H + 1.24W1)
Desulfurization equipment inlet water vapor amount (Qs) = (Q' x fuel consumption x 1000) - (Q” x fuel consumption x 1000)
Amount of steam at the outlet of the desulfurization device (Qc) = (Q' x fuel consumption x 1000 x 1.3 - Qs/1.244) x 0.077 x 1.244
Amount of gas generated by the denitrification device (Qa) = Qc - Qs + 10000
Exhaust gas volume (wet) = Q' x fuel consumption x 1000 + Qa
Exhaust gas volume (dry) = (Q" x fuel consumption x 1000) + 10000
(In the above formula 2, C means carbon, H means hydrogen, O means oxygen, S means total sulfur, W1 means total water, and N means nitrogen.)
The fuel consumption calculation unit calculates the second exhaust gas component concentration prediction value and the maximum prediction value (p2) of the fuel consumption amount by the following (Equation 3),
(Formula 3) Dust concentration in exhaust gas = A x ((Fuel consumption - (Fuel consumption x (W1 - W2)) x 1000/Q" x 1000)
(In the above formula 3, A represents ash content, W1 represents total moisture, and W2 represents inherent moisture.)
The fuel consumption calculation unit calculates a maximum predicted value of fuel consumption from the maximum predicted value of fuel consumption (p1) and the maximum predicted value of fuel consumption (p2), such that the second exhaust gas component concentration and the exhaust gas amount are both within predetermined threshold values . A coal and biomass operation support system. A means for acquiring a measurement value of the first exhaust gas component concentration;
The coal and biomass operation support system according to claim 1 , further comprising: a means for acquiring the measured value of the fuel consumption. a first determination unit that determines whether the first exhaust gas component concentration prediction value is within a predetermined threshold value;
a second determination unit that determines whether the maximum predicted value of the fuel consumption is equal to or greater than a predetermined threshold value,
The coal and biomass management support system according to claim 1 or 2, wherein the output unit outputs the determination results of the first determination unit and the second determination unit. A step of selecting the one or more types of coal or biomass fuel and a coal blending ratio;
and a determination step of determining whether or not the single type of coal or the blended coal, or the fuel obtained by mixing the coal and the biomass fuel, is usable by comparing the first exhaust gas component concentration prediction value and the maximum prediction value of the fuel consumption amount with respective predetermined threshold values ,
The coal and biomass operation method using the coal and biomass operation support system according to any one of claims 1 to 3 , wherein the selection step and the determination step are executed by a computer device . a monitoring step of comparing the measured value of the first exhaust gas component concentration, the measured value of the second exhaust gas component concentration, and the measured value of the fuel consumption amount with respective predetermined threshold values;
Based on the result of the monitoring step, a method for calculating the first exhaust gas component concentration predicted value or a method for calculating the maximum predicted value of the fuel consumption amount is reviewed;
The monitoring step is performed by a computer device;
The coal and biomass operation method using the coal and biomass operation support system according to claim 2 or 3 , wherein the calculation method of the first exhaust gas component concentration predicted value or the calculation method of the maximum predicted value of the fuel consumption amount is reviewed by a user . A function for accepting input of property item values and blending ratios of one or more types of coal or biomass fuel;
An exhaust gas component concentration calculation function that calculates a first exhaust gas component concentration prediction value from the property item values and the coal blending ratio of the one or more types of coal or biomass fuel;
A fuel consumption calculation function that calculates a maximum predicted value of fuel consumption at which the second exhaust gas component concentration and the exhaust gas amount are both within a predetermined threshold value based on the property item values and the coal blending ratio of the one or more types of coal or biomass fuel;
a first determination function for determining whether the first exhaust gas component concentration prediction value is within a predetermined threshold value;
a second determination function for determining whether the maximum predicted value of the fuel consumption is equal to or greater than a predetermined threshold;
an output function of a determination result by the first determination function and the second determination function ;
The first exhaust gas component includes nitrogen oxides, and the second exhaust gas component includes soot and dust,
The property item values include carbon, hydrogen, oxygen, total sulfur, total moisture, nitrogen, ash, and inherent moisture;
The exhaust gas component concentration calculation function calculates the first exhaust gas component concentration prediction value by the following (Equation 1):
(Equation 1) NOx concentration in exhaust gas = 19.3 x fuel ratio x (1 + fuel nitrogen content (%, CH base)) + 97 (ppm)
(In the above formula 1, "CH base" indicates an analysis value at a constant humidity of 75%. The fuel ratio is calculated from the ratio of fixed carbon to volatile matter.)
The fuel consumption calculation function calculates a maximum predicted value (p1) of fuel consumption by the following (Equation 2):
(Formula 2) Theoretical air amount ((A0)) = 8.89C + 26.7 × (HO / 8) + 3.33S
Theoretical combustion gas amount (Q0) = 1.867C + 0.7S + 11.2H + 1.24W1 + 0.8N + 0.79A0
Actual combustion gas volume (wet) (Q') = Q0 + (1.31-1) x A0
Actual combustion gas volume (dry) (Q") = Q' - (11.2H + 1.24W1)
Desulfurization equipment inlet water vapor amount (Qs) = (Q' x fuel consumption x 1000) - (Q” x fuel consumption x 1000)
Amount of steam at the outlet of the desulfurization device (Qc) = (Q' x fuel consumption x 1000 x 1.3 - Qs/1.244) x 0.077 x 1.244
Amount of gas generated by the denitrification device (Qa) = Qc - Qs + 10000
Exhaust gas volume (wet) = Q' x fuel consumption x 1000 + Qa
Exhaust gas volume (dry) = (Q" x fuel consumption x 1000) + 10000
(In the above formula 2, C means carbon, H means hydrogen, O means oxygen, S means total sulfur, W1 means total water, and N means nitrogen.)
The fuel consumption calculation function calculates the second exhaust gas component concentration prediction value and the maximum prediction value (p2) of the fuel consumption amount by the following (Equation 3):
(Formula 3) Dust concentration in exhaust gas = A x ((Fuel consumption - (Fuel consumption x (W1 - W2)) x 1000/Q" x 1000)
(In the above formula 3, A represents ash content, W1 represents total moisture, and W2 represents inherent moisture.)
The fuel consumption calculation function calculates a maximum predicted value of fuel consumption from the maximum predicted value of fuel consumption (p1) and the maximum predicted value of fuel consumption (p2), such that the second exhaust gas component concentration and the exhaust gas amount are both within predetermined threshold values . A coal and biomass operation support program.

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