JP7315528B2 - DISPLAY DEVICE AND DISPLAY METHOD FOR ASSISTING PROCESS CONTROL - Google Patents

Description

The present invention relates to display devices and display methods for assisting process control.

A process system such as a chemical plant or a power plant has a part that is automatically operated by control logic and a part that is operated based on fixed values manually set by an operator. In the process control for such a process system, the operator appropriately adjusts the control parameters used for automatic operation and the fixed values manually set while monitoring the operating state to maintain the operating state optimally.

Some control parameters and fixed values in process control can be optimized by deductive calculation, but in many cases it is difficult to calculate theoretically, and operators adjust by repeating trial and error.

JP 2017-211839 A JP 2017-228254 A

The adjustment of control parameters and fixed values by trial and error by the operator involves repeating the procedure of changing the setting value by a small amount, confirming the change in the entire process, determining that there is no problem, and then changing the setting value by a small amount, in order to give top priority to the continuation of stable operation of the process system, and it takes a lot of time and effort to obtain the desired result. In addition, if the operator erroneously changes the set value, there is a risk that the continuation of stable operation of the process system and the legally regulated factors such as exhaust gas concentration will be significantly affected.

It is an exemplary object of some aspects of the present invention to provide support techniques for keeping process-based systems in optimum operating condition.

In order to solve the above-described problems, a display device according to one aspect of the present invention is a display device for supporting process control, comprising: a selection unit that allows the operator to select at least one of a manually input process value that can be changed by the operator and a target process value that should be controlled to a predetermined target value from among a plurality of process value candidates; a correlation identification unit that identifies one or more related process values that are directly or indirectly correlated with at least one of the selected manual input process value and the target process value; and a display section for displaying graphs showing relationships side by side.

According to this aspect, a related process value that correlates with a manual process value or a target process value in process control can be identified and variations in the two correlated process values can be graphically identified.

Another aspect of the invention is a display method. This method is a display method for supporting process control, comprising a selection step of having the operator select at least one of a manually input process value that can be changed by the operator and a target process value to be controlled to a predetermined target value from among a plurality of process value candidates; a correlation identification step of identifying one or more related process values that have a direct or indirect correlation with at least one of the selected manual input process value and the target process value; Including.

It should be noted that any combination of the above-described constituent elements and the mutual substitution of the constituent elements and expressions of the present invention in methods, devices, systems, computer programs, data structures, recording media, etc. are also effective as aspects of the present invention.

ADVANTAGE OF THE INVENTION According to this invention, the support technology for maintaining a process system system in the optimal operating state can be provided.

1 is a configuration diagram of a display device for supporting process control according to the present embodiment; FIG. FIG. 10 is a diagram showing an example of a selection screen for manually input process values and target process values; FIG. 2 is a diagram showing chain paths presented as options by the option presentation unit in FIG. 1; Figure 4 shows details of the first option of Figure 3; Figure 4 shows details of the third option of Figure 3; FIG. 4 is a diagram showing details of the fourth option of FIG. 3; 5(a) to 5(d) are scatter plots showing the correlation of two process values. FIGS. 6(a) to 6(d) are diagrams showing upper and lower limits in the scatter diagrams of FIGS. 5(a) to 5(d), respectively. FIGS. 7A to 7D are diagrams showing the range of possible values of one process value when the other process value is a predetermined value in a scatter diagram showing the correlation between two process values. FIGS. 8(a) to 8(d) are graphs showing, in frequency distribution, values that one process value can take when the other process value is a predetermined value among two correlated process values. Figures 9(a)-9(d) are scatter plots showing the correlation of two process values in a chain path. FIGS. 10(a) to 10(d) are diagrams showing, in frequency distribution, the values that one of two process values that are correlated in the chain path can take when the other process value is a predetermined value. FIGS. 11(a) to 11(d) are diagrams showing how other process values change when a manually input process value is changed. FIGS. 12(a) and 12(b) are diagrams showing how the side effect process values exceed the allowable range and the regulation range due to changes in the manually input process values. FIG. 3 is a diagram showing a specific example of a chain route presented as an option by the option presentation unit of FIG. 1; 14 shows details of the first option of FIG. 13; FIG. FIG. 14 shows details of the second option of FIG. 13; 14 shows details of the third option of FIG. 13; FIG. FIG. 14 is a diagram showing details of the fourth option of FIG. 13;

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described below based on preferred embodiments with reference to the drawings. The same or equivalent constituent elements, members, and processes shown in each drawing are denoted by the same reference numerals, and duplication of description will be omitted as appropriate. Moreover, the embodiments are illustrative rather than limiting the invention, and not all features and combinations thereof described in the embodiments are necessarily essential to the invention.

FIG. 1 is a configuration diagram of a display device 100 for supporting process control according to this embodiment. The display device 100 is configured as part of an operation support device for process systems such as chemical plants and power plants. Display device 100 includes process value selection unit 10, correlation identification unit 20, option presentation unit 30, process value input unit 40, correlation display unit 50, warning unit 60, correlation storage unit 70, and operation data DB (database) 80.

In process control, multiple process variables are correlated, so it is not possible to manage the entire process by focusing only on the value of one process variable. Therefore, it is necessary to grasp the operating conditions while looking at the correlations between a plurality of process variables.

Correlation storage unit 70 stores correlations between a plurality of process variables. Some correlations between process variables are described by theoretical formulas, while others are obtained empirically.

In the operation data DB 80, values of process variables when the process system is actually operated are registered as operation data. Operation data is collected as needed by various permanent or temporary instruments and continuously accumulated in the operation data DB 80, so not only current operation data but also past operation data can be referred to.

The process value selection unit 10 allows the operator to select a "target process value" to be controlled to a predetermined target value from among a plurality of process value candidates. The process value selection unit 10 may also allow the operator to select a “manually input process value” whose value can be changed by the operator from among a plurality of process value candidates. Manually-inputted process values can also be automatically found by the correlation identification unit 20 as described later, so selection of manually-inputted process values by the operator is not essential.

FIG. 2 is a diagram showing an example of a selection screen for manually input process values and target process values. The screen of the display device 100 displays a manually input process value selection window 200 for allowing the operator to select a manually input process value and a target process value selection window 210 for allowing the operator to select a target process value. By scrolling the items in the window up and down, it is possible to view the part that cannot be displayed.

The manually input process value selection window 200 displays a plurality of manually input process value candidates whose values can be changed by the operator, and the operator appropriately selects the manually input process value whose setting value is to be changed to improve the operating condition from among the plurality of manually input process value candidates. If the operator does not know which manual process value to adjust, he or she may not select any manual process value and let the correlation identifier 20 automatically select one. In the example of FIG. 2, the operator has selected process value A, process value B, and process value D as manual input process values, and these process values are highlighted.

The target process value selection window 210 displays a plurality of target process value candidates to be controlled to a predetermined target value, and the operator selects a target process value to be controlled to a target value in order to improve the operating conditions from among the plurality of target process value candidates. In the example of FIG. 2, the operator has selected process value Q as the target process value and process value Q is highlighted.

The correlation identifying unit 20 refers to the correlation storage unit 70 to identify a "related process value" that has a direct or indirect correlation with the target process value selected by the operator. A related process value that is directly correlated with the target process value is identified, another related process value that is directly correlated with the related process value is identified, and this is repeated to obtain a chain path of one or more related process values that are chain-correlated with the target process value.

A manual process value whose value can be changed by the operator may be found in the chain path of related process values that are directly or indirectly correlated with the target process value. The manual process values found in the chain path of related process values may be manual process values selected by the operator in the manual process value selection window 200 or manual process values not selected in the manual process value selection window 200.

The option presenting unit 30 presents, as options, a chain path from the manually input process value to the target process value via the related process value.

FIG. 3 is a diagram showing chain paths presented as options by the option presentation unit 30. As shown in FIG. The options for each chain path are displayed in order of option identifier 300 , manual process value 302 , associated process value 304 , target process value 306 , and risk 308 . Risk 308 is optional and may not be displayed.

The first option 220 is shown in order of option identifier S1, manual input process value A, first relevant process value X1, second relevant process value X2, third relevant process value X3, target process value Q, high risk. The manually input process value A is directly correlated with the first related process value X1, the first related process value X1 is directly correlated with the second related process value X2, the second related process value X2 is directly correlated with the third related process value X3, the third related process value X3 is directly correlated with the target process value Q, and the process value A, the process value X1, the process value X2, the process value X3, and the process value Q are correlated in a chained order.

Similarly, the second option 230 has option identifier S2, and is linked and correlated in the order of manual input process value B, fourth related process value X4, fifth related process value X5, sixth related process value X6, seventh related process value X7, and target process value Q, and is high risk.

A third option 240 has option identifier S3 and is correlated and at risk in the following order: manual input process value D, eighth related process value X8, ninth related process value X9, target process value Q.

The fourth option 250 has the option identifier S4 and is linked and correlated in the order of the manual input process value F, the tenth relevant process value X10, the eleventh relevant process value X11, the twelfth relevant process value X12, and the target process value Q, and is low risk.

The manually input process values A, B, and D of the first option 220, the second option 230, and the third option 240 are the manually input process values selected by the operator in the manual process value selection window 200, but the manual process value F of the fourth option 250 is the manually input process value that the operator did not select in the manual process value selection window 200, and was automatically found by the correlation identification unit 20.

When the operator clicks on each option 220, 230, 240, 250 in FIG. 3, details of each option 220, 230, 240, 250 are displayed, and side effect process values that are affected as side effects from the related process values are displayed.

FIG. 4A is a diagram showing details of the first option 220 of FIG. The first related process value X1 is directly correlated with the first side effect process value Y1, the second related process value X2 is directly correlated with the second side effect process value Y2, and the third related process value X3 is directly correlated with the third side effect process value Y3 and the fourth side effect process value Y4.

Of the side effect process values shown in FIG. 4A, the first side effect process value Y1 and the fourth side effect process value Y4 are risky items, so a mark (referred to as a "risk mark") indicating that they are risk items is displayed. The first option 220 is designated as "high" risk because there are two risky side effect processes. When evaluating the risk, the risk may be statically evaluated based on whether the side effect process value is a risk factor or not, or the risk may be dynamically evaluated based on whether the side effect process value exceeds the allowable range. When statically assessing risk, it is possible to assess risk quickly and simply because the evaluation is based solely on the nature of whether or not the process value of side effects poses a risk, without simulating what specific value the process value of side effects will be. When the risk is dynamically evaluated, it is evaluated based on whether or not the side effect process value exceeds the allowable range as a result of the simulation. By estimating the risk low if it falls within the allowable range and estimating the risk high if it exceeds the allowable range, specific and accurate risk assessment is possible. Also, the risk determination results may be quantitatively indicated by numerical values. Quantitatively showing risks in numerical values makes it possible to more accurately ascertain the level of risk and to easily compare risks between options.

FIG. 4B is a diagram showing details of the third option 240 of FIG. The eighth related process value X8 is directly correlated with the fifth side effect process value Y5 and the ninth related process value X9 is directly correlated with the sixth side effect process value Y6. The sixth side effect process value Y6 is also directly correlated with the seventh side effect process value Y7.

Of the side effect process values shown in FIG. 4B, the seventh side effect process value Y7 is a risk item, so a risk mark is displayed. The third option 240 is marked as medium risk because there is one risky side effect process.

FIG. 4C is a diagram showing details of the fourth option 250 of FIG. The tenth related process value X10 is directly correlated with the eighth side effect process value Y8, the eleventh related process value X11 is directly correlated with the ninth side effect process value Y9, and the twelfth related process value X12 is directly correlated with the tenth side effect process value Y10.

Since the side effect process value shown in FIG. 4C has no risk item, the risk of the fourth option 250 is "low".

In this way, the operator can browse the details of each option, confirm what side effects are involved, and check the presence or absence and degree of risk of side effects.

In this example, the fourth option 250 has the lowest risk, so it is the option that the operator chooses as the best option. Since the manual process value F of the fourth option 250 was not selected by the operator in the manual process value selection window 200, the operator was able to find a chain path that he could not have found himself as a means of controlling the target process value Q to the target value.

The correlation display unit 50 selects two process values in the chain path of each option and displays a graph showing the correlation between the two process values. Multiple side-by-side graphs showing the correlation between two process values in a chain may be displayed to view changes in related process values along the chain path.

The correlation display unit 50 can refer to the operation data DB 80 and display the upper limit value and the lower limit value that two process values can take in a scatter diagram showing the correlation between the two process values using the process control operation data for a predetermined period in the past.

5(a) to 5(d) are scatter plots showing the correlation of two process values. FIGS. 5(a), 5(b), 5(c), and 5(d) are scatter diagrams showing the correlation between process value X and process value Y using operation data for the past one month, three months, six months, and one year, respectively. It is also possible for the operator to specifically specify the period of the operating conditions that the operator wants to check and display the scatter diagram. For example, since the operating state of a plant is affected by seasonal variations in temperature, humidity, etc., a scatter diagram may be displayed by designating a period such as summer or winter.

FIGS. 6(a) to 6(d) are diagrams showing upper and lower limits in the scatter diagrams of FIGS. 5(a) to 5(d), respectively. 6(a), 6(b), 6(c), and 6(d) are scatter diagrams showing the correlation between the process value X and the process value Y using operation data for the past one month, three months, six months, and one year, respectively. This allows the operator to confirm the range of values that the process value Y can take when the process value X is changed. As a method of mathematically obtaining the upper and lower limits, the method of least squares or simple linear function approximation may be used, or they may be arbitrarily set as the error of the approximation function.

Further, the correlation display unit 50 can also use the operation data of the process control for a predetermined period in the past to display the possible values of one of the two process values when the other process value is set to a predetermined value in a frequency distribution.

FIGS. 7A to 7D are diagrams showing the range of possible values of one process value when the other process value is a predetermined value in a scatter diagram showing the correlation between two process values. FIGS. 7(a), 7(b), 7(c), and 7(d) are scatter diagrams showing the correlation between the process value X and the process value Y using operation data for the past one month, three months, six months, and one year, respectively, and are diagrams showing the range of values that the process value Y can take when the process value X is a predetermined value indicated by a vertical bar.

FIGS. 8(a) to 8(d) are graphs showing, in frequency distribution, values that one process value can take when the other process value is a predetermined value among two correlated process values. FIGS. 8(a), 8(b), 8(c), and 8(d) are diagrams showing, in a frequency distribution, the possible values of the process value Y when the process value X is a predetermined value indicated by a vertical bar in the scatter diagram showing the correlation between the process value X and the process value Y using operation data for the past one month, three months, six months, and one year, respectively. The horizontal axis is the value of the process value Y, and the vertical axis is the frequency of the process value Y. FIG. Dotted lines indicate the upper and lower limits of the frequency distribution. The upper and lower limits can be set at arbitrary multiples of the standard deviation.

The correlation display unit 50 displays a plurality of scatter diagrams or frequency distributions showing the correlation of two process values in the chain path side by side, so that it is possible to confirm the influence of the adjustment of the manually input process value on the target process value via the related process value.

Figures 9(a)-9(d) are scatter plots showing the correlation of two process values in a chain path. Here, the case of the first option 220 in FIG. 4A will be described. FIG. 9(a) shows the upper and lower limits of a scatter diagram of the correlation between the manually input process value A and the first related process value X1. FIG. 9(b) shows the upper and lower limits of the scatter diagram of the correlation between the first related process value X1 and the second related process value X2. FIG. 9(c) shows the upper and lower limits of the scatter diagram of the correlation between the second related process value X2 and the third related process value X3. FIG. 9(d) shows the upper and lower limits of the scatter diagram of the correlation between the third related process value X3 and the target process value Q. FIG.

FIGS. 10(a) to 10(d) are diagrams showing, in frequency distribution, the values that one of two process values that are correlated in the chain path can take when the other process value is a predetermined value. Here, the case of the first option 220 in FIG. 4A will be described. FIG. 10(a) shows a frequency distribution of possible values of the first related process value X1 when the manually input process value A is a predetermined value. FIG. 10(b) shows a frequency distribution of possible values of the second related process value X2 when the first related process value X1 is a predetermined value. FIG. 10(c) shows a frequency distribution of possible values of the third related process value X3 when the second related process value X2 is a predetermined value. FIG. 10(d) shows a frequency distribution of possible values of the target process value Q when the third related process value X3 is a predetermined value.

The process value input unit 40 allows the operator to input an input value for the manually input process value for each option. The operator may give the input value numerically, or may continuously change the manually input process value from the current value by sliding a slider (knob) on the axis of the manually input process value in the graph showing the correlation displayed by the correlation display unit 50. The correlation display unit 50 can display changes in the related process value, the side effect process value, and the target process value when the manually input process value is changed to the input value given by the operator in the graph showing the correlation.

FIGS. 11(a) to 11(d) are diagrams showing how other process values change when a manually input process value is changed. Here, the case of the first option 220 in FIG. 4A will be described. FIG. 11A shows a case where the manual input process value A is increased from the current value indicated by the solid line to the set value indicated by the dotted line by sliding the slider indicated by the triangle on the horizontal axis of the graph. As the manually input process value A increases, the first related process value X1, the second related process value X2, the third related process value X3, and the target process value Q change in a chain reaction.

As shown in FIG. 11(a), there is a positive correlation between the manually input process value A and the first related process value X1. Therefore, when the manually input process value A increases, the first related process value X1 also increases. Since the first related process value X1 and the second related process value X2 have a negative correlation as shown in FIG. 11(b), the second related process value X2 decreases when the first related process value X1 increases. Since the second related process value X2 and the third related process value X3 have a negative correlation as shown in FIG. 11(c), the third related process value X3 increases when the second related process value X1 decreases. Since there is a negative correlation between the third related process value X3 and the target process value Q as shown in FIG. 11(d), the target process value Q decreases when the third related process value X3 increases.

Here, if the goal is to decrease the target process value Q, increasing the manually input process value A causes the related process value X1 to increase, the related process value X2 to decrease, the related process value X3 to increase, and the target process value Q to decrease, thereby achieving the objective.

A warning unit 60 outputs a warning by a message, a risk mark, or the like, if a related process value or a side effect process value exceeds a permissible range or a legally regulated range when a manually input process value is changed to an input value set by an operator.

FIGS. 12(a) and 12(b) are diagrams showing how the side effect process values exceed the allowable range and the regulation range due to changes in the manually input process values. Here, the case of the first option 220 in FIG. 4A will be described. FIG. 12(a) shows that when the first process value X1 increases as shown in FIG. 11(b), the first side effect process value Y1, which has a negative correlation with the first process value X1, decreases and falls below the lower limit α. FIG. 12(b) shows that when the third process value X3 increases as shown in FIG. 11(d), the fourth side effect process value Y4, which has a positive correlation with the third process value X3, increases and exceeds the upper limit value β.

When the related process value or the side effect process value exceeds the allowable range or the regulatory range, the warning unit 60 may issue a warning by displaying a risk mark on the option detail screen described in FIGS. As shown in FIGS. 12(a) and 12(b), by displaying the limit values and regulation values in the graph and changing the manually input process values, it may be possible to visually confirm that the related process values and the side effect process values exceed the allowable range and the regulation range.

As an example, a case where the display device 100 is applied to process control of a circulating fluidized bed boiler will be described. In a CFB boiler, the calorific value and theoretical air amount can be estimated by back calculation from the actual process, but it is very difficult to estimate parameters such as furnace temperature, which change slowly in the process, by back calculation. By using the display device 100 of the present embodiment, it is possible to easily predict, based on the past operation data, the fluctuation range of the chain-related process values, which is difficult to easily estimate for manually input process value adjustments. In addition, before actually changing the manually input process value, it is possible to evaluate in advance the side effect on the entire process including the fluctuation of the side effect process value.

As an example, there are correlations between the primary air ratio and the bed temperature of the CFB boiler, between the bed temperature and the amount of nitrogen oxides (NOx) generated, and between the primary air ratio and the amount of nitrogen oxides generated. When controlling the bed temperature, which is the target process value, to the target value by adjusting the primary air ratio as a manually input process value, it is required to suppress the generation amount of nitrogen oxides, which is a side effect process value, below the regulation value. By adjusting the primary air ratio while checking the correlation between the primary air ratio, the amount of nitrogen oxides generated, and the bed temperature on a graph based on the operating data, it is possible to control the bed temperature to the target value while suppressing the amount of nitrogen oxides generated.

FIG. 13 is a diagram showing a specific example of chain routes presented as options by the option presentation unit 30. In FIG. Here, an example will be described in which the target process value of the CFB boiler is set to lower the exhaust gas temperature at the boiler outlet as the control target.

First, second, third, and fourth options 260, 270, 280, and 290 are presented, and the manual input process value 302 is "air ratio function setting change (increase)," "air ratio function setting change (decrease)," "theoretical air amount setting value change," and "combustion air distribution setting value change," respectively, and the target process value 306 is "boiler exit exhaust gas temperature decrease." "Air ratio function setting change (increase)" and "air ratio function setting change (decrease)" mean that the air ratio is changed in the direction of increasing or decreasing, respectively, and the manual input process value can also be defined including the direction of changing the set value in this way.

In the first option 260, the related process values 304 for the manually input process value "air ratio function setting change (increase)", "air ratio increase", "total combustion air amount increase", "exhaust gas amount increase", "furnace heat absorption increase", and "furnace exit exhaust gas temperature decrease" are linked in this order, and a chain path leading to the target process value "boiler exit exhaust gas temperature decrease" is presented.

Here, the direction of change such as "increase" or "decrease" is shown for each related process value, in terms of a graph showing correlation, depending on whether the correlation is positive or negative with respect to the increase or decrease in the previous related process value. Even if the graph showing the correlation is not displayed, the increase or decrease of each related process value can be displayed as a character string.

In the second option 270, the related process values 304 for the manually input process value "air ratio function setting change (decrease)", "air ratio decrease", "total combustion air amount decrease", "exhaust gas amount decrease", "furnace heat absorption decrease", "furnace outlet exhaust gas temperature increase", and "rear flue heat exchanger performance improvement" are chained in this order, and a chain path leading to the target process value "boiler outlet exhaust gas temperature decrease" is presented.

In the third option 280, the related process values 304 for the manual input process value "change theoretical air amount setting value", "increase primary combustion air amount only", "increase furnace heat absorption amount", and "furnace exit exhaust gas temperature decrease" are chained in this order, and a chain path leading to the target process value "boiler exit exhaust gas temperature decrease" is presented. The reason why the "increase in the amount of primary combustion air only" is linked to the "increase in the amount of heat absorbed by the furnace" is that the activity of the circulating material, which is the heat transfer medium in the furnace, becomes active.

In the fourth option 290, the related process value 304 for the manually input process value "combustion air distribution set value change" is linked in this order with "primary combustion air amount only increase", "furnace heat absorption amount increase", and "furnace exit exhaust gas temperature decrease", and a chain path leading to the target process value "boiler exit exhaust gas temperature decrease" is presented.

FIG. 14A is a diagram showing details of the first option 260 of FIG. Side effect process values are shown, and side effect process values at risk are marked with a risk mark.

The related process value "air ratio increase" correlates with the side effect process value "NOx generation amount increase", "total combustion air amount increase" correlates with the side effect process value "secondary forced draft fan power consumption increase", "exhaust gas amount increase" correlates with the side effect process value "induced fan power consumption increase" and "boiler efficiency decrease", "furnace heat absorption increase" correlates with the side effect process value "furnace temperature decrease", and the side effect process value "furnace temperature decrease" is also a side effect. There is a correlation with the process value "decreased desulfurization efficiency (increased SOx emissions)".

Here, the side effect process value "decreased boiler efficiency" is a risk item. This is because if the boiler efficiency drops, the original purpose of the boiler is not achieved. In addition, "desulfurization efficiency decrease (increase in SOx emissions)" is also a risk item. This is because emissions of sulfur oxides (SOx) are regulated by law from the viewpoint of air pollution, and exceeding the regulated value is a violation of the law.

Here, there is an appropriate temperature range for the desulfurization reaction, but in this example, due to the adjustment of the manually input process value "air ratio function setting change (increase)", the temperature falls below the appropriate temperature, the desulfurization reaction stops, and the SOx emission amount exceeds the regulation value. Therefore, the first option 260 cannot be adopted.

FIG. 14B is a diagram showing details of the second option 270 of FIG. "Total combustion air amount decrease" correlates with the side effect process value "secondary forced draft fan consumption power increase", "exhaust gas amount decrease" correlates with the side effect process value "induced fan power consumption increase", "furnace heat absorption decrease" correlates with the side effect process value "furnace temperature increase", and the side effect process value "furnace temperature increase" further correlates with the side effect process values "desulfurization efficiency decrease (SOx emissions increase)" and "NOx generation increase".

Here, "decrease in desulfurization efficiency (increase in SOx emissions)" and "increase in NOx generation" are risk items. This is because, from the viewpoint of air pollution, the amount of nitrogen oxides (NOx) generated is also regulated by law, as is the case with sulfur oxides (SOx).

In addition, it is also displayed as a risk item related to manually input process values that the manually input process value "air ratio function setting change (decrease)" is not applicable in the high operating load zone of the boiler.

In this example, due to the adjustment of the manually input process value "air ratio function setting change (decrease)", the temperature becomes below the temperature at which the desulfurization reaction occurs, the desulfurization reaction stops, and the SOx emission amount exceeds the regulation value, and the NOx emission amount also exceeds the regulation value, so the second option 270 cannot be adopted.

FIG. 14C is a diagram showing details of the third option 280 of FIG. "Increase in primary combustion air amount only" is correlated with the side effect process value "increase in power consumption of primary forced draft fan" and "decrease (or loss) of exhaust gas O2 correction function by secondary forced draft fan", "increase in furnace heat absorption" is correlated with the side effect process value "decrease in furnace temperature", and the side effect process value "decrease in furnace temperature" is further correlated with the side effect process value "decrease in desulfurization efficiency (increase in SOx emissions)".

Here, "decreased desulfurization efficiency (increased SOx emissions)" is a risk item. In addition, the manually input process value “change of theoretical air amount set value” is displayed as a risk item related to the manually input process value that needs to be set again when the operational load is changed.

In this example, the third option 280 cannot be adopted because the adjustment of the manually input process value "change theoretical air amount set value" causes the SOx emission amount to exceed the regulation value.

FIG. 14D is a diagram showing details of the fourth option 290 of FIG. "Increase in primary combustion air only" correlates with the side effect process value "increase in power consumption of primary forced draft fan" and "decrease (or loss) of exhaust gas O2 correction function due to secondary forced draft fan". There is a correlation with the heat exchanger performance degradation in the aft flue”.

In this example, even if the manually input process value "combustion air distribution set value change" is adjusted, the amount of SOx emissions does not exceed the regulation value. Therefore, the fourth option 290 can be adopted as a means that can be operated with the least risk, and by adjusting the combustion air distribution to a set value that matches the load, the exhaust gas temperature at the boiler outlet can be lowered to the target value.

As described above, according to the display device 100 of the present embodiment, it is possible to check the related process value and the side effect process value of the chain path leading from the manually input process value to the target process value. Therefore, it is possible to check the change of the related process value and the side effect process value that would be overlooked by just looking at the change of the target process value when the manually input process value is adjusted.

Further, according to the display device 100, the operator can predict the degree of change in the process value that will have an effect before actually changing the set value of the manually input process value, and can stop changing the set value of the manually input process value if there is an adverse effect. Specifically, it is possible to predict the degree of change in related process values that are directly correlated to manually input process values, and further predict the degree of change in related process values and side effect process values that are chain-correlated. In addition, since graphs showing the correlation of two correlated process values can be displayed in parallel, when a manually input process value is adjusted, it is possible to predict the change width of other directly or indirectly correlated process values all at once.

Further, according to the display device 100, by using the past operation data, it is possible to easily find out the optimal value for the process value that has been adjusted based on experience.

In general, when evaluating the correlation between process values in numerical simulation, it is necessary to define a transfer function, but it is difficult to set the time constant, time delay, various coefficients, and constants included in the transfer function. On the other hand, according to the display device 100 of the present embodiment, the correlation between the process values can be graphically displayed from the actual operation data and checked. In addition, since it can be evaluated from actual operation data regardless of plant characteristics (e.g., calorific value, fuel type, steam temperature, pressure, flow rate, etc.), this method is not limited to individual plant differences, and can be widely applied not only to combustion plants but also to a wide variety of process systems including chemical plants, and has high versatility.

Thus, according to the display device 100 of the present embodiment, it is possible to significantly reduce the labor of the operator and contribute to stable operation of the plant.

The present invention has been described above based on the examples. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments, and that various design changes and modifications are possible, and that such modifications are within the scope of the present invention.

It can be used in display technology to aid in process control.

10 process value selection unit 20 correlation identification unit 30 option presentation unit 40 process value input unit 50 correlation display unit 60 warning unit 70 correlation storage unit 80 operation data DB 100 display device.

Claims (11)

A display device for supporting process control, comprising:
a selection unit that allows an operator to select a target process value to be controlled to a predetermined target value from among a plurality of process value candidates;
a correlation identifier that identifies one or more related process values that are directly or indirectly correlated with the operator-changeable manual process value and the selected target process value;
A display unit for displaying side by side a graph showing the correlation between the manually input process value and the related process value directly correlated with the manually input process value, a graph showing the correlation between the two related process values directly correlated in a chain, and a graph showing the correlation between the target process value and the related process value directly correlated with the target process value. 2. The display device according to claim 1, wherein the selection unit allows the operator to select a manually input process value that can be changed by the operator. 3. The display device according to claim 1, wherein the display unit displays the upper limit value and the lower limit value that the two process values can take in a scatter diagram showing the correlation between the two process values using operation data of process control for a predetermined period in the past. 3. The display device according to claim 1 or 2, wherein the display unit displays values that one of the two process values can take when the other process value is set to a predetermined value in a frequency distribution, using operation data of process control for a predetermined period in the past. 5. The display device according to any one of claims 1 to 4, wherein the correlation specifying unit specifies a manually input process value whose value can be changed by the operator, from among the one or more related process values. 6. The display device according to any one of claims 1 to 5, wherein the correlation identifying unit identifies a side effect process value that causes a side effect with respect to the related process value. 7. The display device according to any one of claims 1 to 6, further comprising a presentation unit that presents a chain route of process values having a correlation from the manually input process value to the target process value as options. 8. The display device according to any one of claims 1 to 7, wherein when the manually input process value is changed to an input value set by the operator, the display unit displays a change in the process value in the graph showing the correlation. 9. The display device according to any one of claims 1 to 8, further comprising a warning unit for outputting a warning if the process value specified by the correlation specifying unit exceeds an allowable range or a legally regulated range when the manually input process value is changed to the input value set by the operator. A display method for assisting process control, comprising:
a selection step of causing an operator to select a target process value to be controlled to a predetermined target value from among a plurality of process value candidates;
a correlation identification step of identifying one or more related process values that are directly or indirectly correlated with the operator-changeable manual process value and the selected target process value;
a display step of displaying side by side a graph showing the correlation between the manually input process value and the related process value directly correlated with the manual input process value, a graph showing the correlation between the two related process values directly correlated in a chain, and a graph showing the correlation between the target process value and the related process value directly correlated with the target process value. A program for supporting process control, comprising:
a selection step of causing an operator to select a target process value to be controlled to a predetermined target value from among a plurality of process value candidates;
a correlation identification step of identifying one or more related process values that are directly or indirectly correlated with the operator-changeable manual process value and the selected target process value;
A program for causing a computer to execute a display step of displaying side by side a graph showing the correlation between the manually input process value and the related process value directly correlated with the manual input process value, a graph showing the correlation between the two related process values directly correlated in a chain, and a graph showing the correlation between the target process value and the related process value directly correlated with the target process value.

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