JP2009244061A - State-monitoring system and state-monitoring method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a state-monitoring system and a state-monitoring method, capable of efficiently managing a change with time in the deterioration state of an object to be monitored, in a plant. <P>SOLUTION: An operation means 32 calculates a stress variable Y in real time, based on a process variable acquired by a parameter accumulation means 31. The stress variable Y is a factor that determines the state deterioration of the object to be monitored, such as, speed of corrosion. The stress variable Y is calculated, for example, by a model formula, namely, the stress variable Y=a1×X1+a2×X2, ..., +an×Xn (model formula). Here, X1, X2, ..., Xn are the process variables and a1, a2, ..., an are the coefficients given to respective process variables. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a state monitoring system and a state monitoring method for managing a temporal change in a deterioration state of a monitoring target in a plant.

In the plant, for example, corrosion of the pipe inner surface in the pipe, corrosion of the tube in the heat exchanger, hydrogen embrittlement (hydrogen attack) in the oil desulfurization reactor reaction tower and hydrogen system pipe, hydrogen blister, creep embrittlement in the heating furnace tube, etc. Corrosion and deterioration of equipment occur. For this reason, by periodically inspecting the state of the equipment by non-destructive inspection or the like, the current state of corrosion or deterioration is grasped, and the time for replacing the equipment is specified.
JP 2004-251765 A

  In order to accurately grasp the state of the equipment, it is necessary to frequently perform the inspection as described above, which increases the work cost. Although it is conceivable to estimate the state change of the equipment after the inspection until the next inspection, it is difficult to directly measure the progress of the corrosion and deterioration of the equipment online. In addition, no system has been developed that can handle the results of nondestructive inspections and data related to equipment corrosion and deterioration in an integrated manner. There is a problem that you can not.

  An object of the present invention is to provide a state monitoring system and a state monitoring method capable of efficiently managing a temporal change in a deterioration state of a monitoring target in a plant.

The state monitoring system according to the present invention is a state monitoring system that manages changes over time in the deterioration state of a monitoring target in a plant, collects parameters related to the amount of change in the deterioration state, and corresponds the history of the parameters to the time. Parameter storage means for accumulating, and deterioration of the state of the monitored object per time based on a model formula for converting the value of each parameter accumulated in the parameter storage means into the change amount of the change over time And an arithmetic means for calculating the quantity.
According to this state monitoring system, since the amount of deterioration per time of the state of the monitored object is calculated based on the model formula that converts the value of each parameter into the amount of change over time, the deterioration state of the monitored object Can be managed efficiently over time.

  The calculation means may calculate the deterioration state of the monitoring object or the life of the monitoring object by integrating the calculated deterioration amount per time.

  A state acquisition unit that acquires information indicating the state of the monitoring target; and a model expression generation unit that generates and corrects the model expression so as to match the information acquired by the state acquisition unit. Good.

  State acquisition means for acquiring the state of the monitoring object is provided, and the calculation means starts from the state indicated by the information acquired by the measurement result acquisition means, or the life of the monitoring object or the life of the monitoring object May be calculated.

  The parameter may be information on a process variable, a quality test value, and an oil feed material.

The state monitoring method of the present invention is a state monitoring method for managing a change over time of a deterioration state of an object to be monitored in a plant, collecting parameters related to the amount of change in the deterioration state, and corresponding the history of the parameter to the time. And calculating a deterioration amount per time of the state of the monitoring object based on a model formula that converts the value of each parameter accumulated in the accumulating step into a change amount of the change over time And a step of performing.
According to this state monitoring method, since the amount of deterioration per time of the state of the monitored object is calculated based on the model formula that converts the value of each parameter into the amount of change over time, the deterioration state of the monitored object Can be managed efficiently over time.

  According to the state monitoring system of the present invention, since the amount of deterioration per time of the state of the monitoring target is calculated based on the model formula that converts the value of each parameter into the amount of change over time, It is possible to efficiently manage the change over time in the deterioration state.

  According to the state monitoring method of the present invention, since the amount of deterioration of the state of the monitored object per time is calculated based on the model formula that converts the value of each parameter into the change amount of the change over time, It is possible to efficiently manage the change over time in the deterioration state.

  Hereinafter, an embodiment of a state monitoring system according to the present invention will be described with reference to FIGS.

  FIG. 1A is a block diagram illustrating a configuration of a plant in which the state monitoring system of the present embodiment is used, and FIG. 1B is a functional block diagram illustrating functions of a calculation unit and a model formula creation unit.

  As shown in FIG. 1 (a), the plant includes field control devices 1, 1,... Distributed in each part of the plant and field device groups of the plant via the field control devices 1, 1,. And a monitoring station 2 for operating and monitoring the above in an integrated manner. The field control devices 1, 1,... And the monitoring station 2 are connected to each other by a communication line 5.

  As shown in FIG. 1 (a), the state monitoring system 3 of the present embodiment is connected to the field control devices 1, 1,... And the monitoring station 2 via the communication line 5, and via the communication line 5. Using the obtained process variables and the like, the deterioration state and life of the monitoring target are calculated. As shown in FIG. 1, an operation information system 6 that collects plant operation information and a quality information system 7 that measures quality of products and accumulates measurement results are connected to the state monitoring system 3. .

  The state monitoring system 3 according to this embodiment includes a parameter storage unit 31 that acquires and stores process variables, and a calculation unit 32 that calculates a deterioration state and a life of a monitoring target using the process variables stored in the parameter storage unit 31. A state acquisition unit 33 for acquiring the measurement result of the state of the monitoring object, and a model expression generation for creating and correcting the model expression so as to match the measurement result of the state of the monitoring object acquired by the state acquisition unit 33 Means 34.

  The parameter accumulating unit 31 acquires parameters necessary for calculating the deterioration state and life of the monitoring target from the field control devices 1, 1,..., The operation information system 6, and the quality information system 7.

  For example, in the oil refining equipment, the corrosion of the pipe inner surface of the overhead system piping of the main tower of the atmospheric pressure or the corrosion of the tube in the heat exchanger, There are hydrogen embrittlement (hydrogen attack) and hydrogen blisters in oil desulfurization reactor reaction towers and hydrogen piping, and creep embrittlement in heating furnace tubes.

  FIG. 2 is a diagram showing the concept of the process variables accumulated in the parameter accumulation unit 31 and the state of the monitored object acquired by the state acquisition unit 33.

  The parameter storage means 31 acquires process variables from the field control devices 1, 1,... Via the communication line 5, parameter information from the operation information system 6 and the quality information system 7 as parameters, and stores them. To do. The process variable is a parameter serving as an environmental factor that degrades the state of the monitoring target. For example, the internal fluid's salinity, dew point, pH value, etc. in pipe internal corrosion or heat exchanger tube corrosion, and hydrogen embrittlement (hydrogen attack) in relation to the Nelson curve, etc. The pressure, pressure, temperature, etc. are the hydrogen partial pressure, pressure, temperature, etc. of the internal fluid in the hydrogen blister, and the temperature, pressure, etc. of the internal fluid in creep embrittlement are related to the application of the Larson Miller method. Captured as a variable. The parameter information includes plant operation information obtained from the operation information system 6, quality measurement results obtained from the quality information system 7, and the like.

  In FIG. 2, dot 51, dot 52, and dot 53 represent the values of process variable X1, process variable X2, and process variable X3, respectively, and dot 52 and dot 53 represent parameter information Xn-1 and parameter information Xn, respectively. These parameters (process variable and parameter information) are stored in association with time. The parameter stored in the parameter storage unit 31 may be, for example, a process variable itself periodically acquired from the field control device 1, 1,..., Or a process variable collected within a certain period or A value represented by an average value of parameter information or the like may be used. In FIG. 2, the parameter change is approximated by a line graph.

  On the other hand, the state acquisition means 33 indicates the degree of corrosion or deterioration of the monitored object, and the measurement results of regular and irregular inspections, nondestructive inspection using ultrasonic waves, radiation, etc. during plant operation. The measurement result is given in association with the time common to the process variable.

  These measurement results indicate, for example, the degree of corrosion and deterioration of the monitored object such as the thickness of the pipe, but usually cannot be measured online and are difficult to obtain frequently. Therefore, in the example shown in FIG. 2, while the process variables X1 to X3 are acquired and stored in a relatively short cycle by the parameter storage unit 31, the measurement result of the state of the monitored object is acquired by the state acquisition unit 33. , Acquired and updated in a longer cycle.

  In FIG. 2, a dot 61 indicates the measurement result, and a dotted line 62 connecting the dots 61 indicates a change in the actual measurement value. A dotted line 62 indicates that the state of the monitored object changes from a good state to a more deteriorated state, and the state decreases to the life line 64. However, what can be actually acquired by the state acquisition means 33 is only the temporally discrete measurement results shown as dots 61.

  FIG. 3 is a diagram conceptually showing the calculation contents of the calculation means 32 and the model formula creation means 34.

  The stress variable calculation function 32 a (FIG. 1B) of the calculation means 32 calculates the stress variable Y in real time based on the process variable acquired by the parameter storage means 31. The stress variable Y is a factor that determines the speed of state deterioration of the monitoring target, for example, corrosion.

  The stress variable Y is calculated by, for example, the next stress variable model formula created and corrected by the stress variable model formula creation function 34a (FIG. 1B) of the model formula creation means 34.

Stress variable Y = a1 × X1 + a2 × X2 +... + An × Xn
... (Stress variable model formula)

  Here, X1, X2, ... Xn are parameters, and a1, a2, ... an are coefficients given to the respective parameters. The stress variable model formula shows the correlation between the parameter and the stress variable Y, and the coefficients a1, a2,... An are acquired in the past, for example, the past parameter group stored in the parameter storage means 31 and the past. It is calculated by comparing with the measurement result of the state of the monitored object. In FIG. 3, a dot 71 indicates the value of the stress variable Y calculated by the calculation means 32. The stress variable Y is also stored in association with the time common to the process variable.

  Next, the deterioration degree Δd of the state of the monitoring object is determined by the deterioration degree calculation function 32b (FIG. 1 (b)) of the calculation means 32 and the deterioration degree model expression creation function 34b (FIG. 1 (b) of the model expression creation means 34. )) Is obtained and corrected according to the following formula (1). The deterioration degree calculation function 32b calculates the deterioration degree Δd in real time by repeating the calculation of Expression (1) every time a new stress variable is obtained by the parameter storage unit 31.

  The coefficients α1 and α2 are tuned based on the measurement result of the state of the monitoring object acquired in the past by the deterioration model expression creation function 34b (FIG. 1B). As shown in Expression (1), the deterioration degree calculation function 32b integrates the stress variable over time and calculates an estimated value of the deterioration degree in real time. In FIG. 3, a curve 63 a indicates the degree of deterioration calculated by the calculation means 32. In this case, the coefficient group is tuned so that the initial value of the degree of deterioration matches the measured value of the dot 61a.

  The stress variable model formula creation function 34a and the degradation level model formula creation function 34b of the model creation means 34 each indicate that the estimated value of the degradation degree indicates the actual state each time the state acquisition means 33 obtains the state of the monitored object. As shown accurately, the coefficient group including the coefficients a1, a2,. For example, in FIG. 3, the measurement value indicated by the dot 61b is obtained, so that the curve 63a indicating the estimated value of the degree of degradation and the dot 61b are deviated, indicating the presence of an estimation error. In this case, the stress variable model formula creation function 34a and the deterioration level model formula creation function 34b retune the coefficient group at the stage when the measured value indicated by the dot 61b is obtained, and newly add the stress variable model formula and formula (1). Make corrections to reflect the measured values. As a result, the new initial value of the deterioration level is set to the measured value indicated by the dot 61b, and the stress variable model formula and the formula (1) are corrected.

  In FIG. 3, after such tuning, the estimated value calculated based on the equation (1) is shown as a curve 63b. Each time a new measurement value such as the dot 61c is obtained, the model formula creation means 34 can repeat the tuning of the coefficient group and calculate a more accurate estimated value (curve 63c or the like). In the case of FIG. 3, if the coefficient group is not tuned, it is predicted that the life of the monitoring object will be exhausted earlier than the actual time as shown by the curve 63 a, whereas it depends on the measured value. By performing the correction, it is possible to improve the accuracy of the final life prediction.

  As described above, according to the state monitoring system of the present embodiment, the measurement value about the state of the monitoring target and the process variable are handled as a data group in which the time axes are aligned with each other. It can be effectively used as analysis data relating to the state of the object. In addition, since the state of the monitored object is estimated using a model formula, corrosion and thinning can be monitored by state prediction even during periods when measurement results by nondestructive inspection etc. cannot be obtained, and the time for equipment replacement (Remaining life of equipment) can always be grasped. Furthermore, since the model formula is corrected based on the measurement result, the state of the monitoring object can be accurately predicted. If the prediction result can be displayed at all times, the amount of deterioration such as corrosion at the present time can be always grasped, so that operation can be performed with confidence while confirming safety in long-term continuous operation.

  Moreover, the usage method of a stress variable is not limited to the state prediction and lifetime prediction of a monitoring target object. For example, since a real-time trend of a stress variable can be obtained as described above, real-time process control that suppresses the stress variable can be performed. For example, the deterioration rate can be suppressed by suppressing the stress variable to a certain level or less by adjusting the pH based on the chemical injection amount, or managing the upper limit of the temperature / hydrogen partial pressure. In addition, the process can be controlled more actively so as to minimize the stress variable.

  In the state monitoring system of the present invention, any “amount of deterioration of the state of the monitored object per time” can be used. For example, the elution amount (estimated amount) of Fe and Cu in the water receiving tank resulting from the corrosion may be handled as “the amount of deterioration of the state of the monitored object per time”. In this case, for example, in the case of an oil plant, CRC (coke), oil flow rate, low sulfa heavy oil flow rate, anticorrosive agent, reaction tower temperature, etc., which are related process variables or operation variables, are used as “parameters”. Can do.

  In the state monitoring system of the present invention, the “information indicating the state of the monitored object” acquired by the state acquisition unit is expected to be able to grasp the state of the monitored object more accurately than the “parameter”. If it is, it is not necessary to be information that can directly grasp the state of the monitoring object.

  In the state monitoring system of the present invention, any parameter can be used as the “parameter”. The parameters are not limited to those constituting factors of corrosion and deterioration. For example, the amount or concentration of an elution component (for example, Fe, Cu, etc.) from a pipe or the like that is a monitoring target can be used as the “parameter”. In addition, since the density | concentration of the said component changes based on the state of corrosion and deterioration (corrosion and deterioration speed), this can also be used as "information which shows the state of the monitoring target object" in this invention. In addition, an operation on the plant (for example, presence or absence of a predetermined operation, valve opening, chemical injection amount, etc.) can be used as a “parameter”. By taking in “parameters” that have a strong correlation with the state of the monitored object as much as possible, the state prediction accuracy can be improved. In either case, “information indicating the state of the monitoring object” and “parameter” are handled as data given the same time axis.

  The scope of application of the present invention is not limited to the above embodiment. The present invention can be widely applied to a state monitoring system and a state monitoring method for managing a change with time of a deterioration state of a monitoring target in a plant.

The block diagram which shows the structure of the plant in which the state monitoring system of one Embodiment is used. The figure which shows the concept of the state of the monitoring object acquired by the process variable and state acquisition means which are accumulate | stored in a parameter storage means. The figure which shows notionally the function of a calculating means and a model formula creation means.

Explanation of symbols

3 State Monitoring System 31 Parameter Accumulating Means 32 Computing Means 33 State Obtaining Means 34 Model Formula Creating Means

Claims (6)

In the state monitoring system that manages the change over time of the deterioration state of the monitoring target in the plant,
Parameter storage means for collecting parameters related to the amount of change in the deterioration state and storing history of the parameters in association with time;
Based on a model formula for converting the value of each parameter stored in the parameter storage unit into a change amount of the change over time, a calculation unit that calculates a deterioration amount per time of the state of the monitoring object;
A state monitoring system comprising: 2. The state monitoring system according to claim 1, wherein the calculation unit calculates a deterioration state of the monitoring object or a lifetime of the monitoring object by integrating the calculated deterioration amount per time. State acquisition means for acquiring information indicating the state of the monitoring object;
A model formula creating means for creating and correcting the model formula so as to match the information acquired by the state acquiring means;
The state monitoring system according to claim 1, further comprising: Comprising state acquisition means for acquiring information indicating the state of the monitoring object;
3. The state according to claim 2, wherein the calculation unit calculates the state of the monitoring object or the life of the monitoring object from the state indicated by the information acquired by the measurement result acquisition unit. Monitoring system. The state monitoring system according to claim 1, wherein the parameter is a process variable. In the state monitoring method for managing the change over time of the deterioration state of the monitored object in the plant,
Collecting parameters related to the amount of change in the deterioration state, and storing a history of the parameters in association with time;
Calculating a deterioration amount per time of the state of the monitoring object based on a model formula for converting the value of each parameter accumulated in the accumulating step into a change amount of the temporal change;
A state monitoring method comprising:

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