Cooling System Leak Detection System and Cooling System Leak Detection Method

Abstract

A valve device abnormality detection system that can easily determine valve abnormalities online is provided. [Solution] A control valve 22 controls the flow rate of raw materials supplied to a reaction device 21, a control unit that controls the control valve 22, a raw material flow meter 23 that detects the flow rate of the raw materials, an analyzer 24 that analyzes the products reacted in the reaction device, and a product flow meter 25 that detects the flow rate of the products. The control unit compares the predicted product predicted from the raw material flow meter 23 with the current product obtained from the analyzer 24 and product flow meter 25, and determines whether there is an abnormality based on the difference between the predicted product and the current product.

Description

Technical Field

[0001] The present invention relates to Cooling system leakage a detection system and Cooling system leakage a detection method.

Background Art

[0002] When controlling a control valve provided in a flow path through which a fluid flows, it is known to perform feedback control of the control valve based on the flow rate obtained by a flow meter (Patent Document 1). This document discloses a method of detecting an abnormality in an apparatus constituting a control loop by using a check signal instead of a control signal for the control loop performing feedback control.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, the above document has a problem that it is necessary to give a check signal and the control becomes complicated.

[0005] When operating a plant such as a gasification furnace or a combustion furnace, it is desired to improve the plant operation rate by detecting a valve abnormality online during operation and performing repair or replacement at an appropriate timing during regular inspection.

[0006] In view of such circumstances, the present disclosure Detect leakage of cooling water from the cooling system is capable of Cooling system leakage providing a detection system and Cooling system leakage a detection method.

Means for Solving the Problems

[0007] A valve device abnormality detection system according to an aspect of a reference example of the present invention includes a control valve provided in a pipe through which a fluid flows, a temperature sensor that measures the temperature of the fluid flowing through the control valve, an upstream pressure sensor that measures the fluid pressure on the upstream side of the control valve, a downstream pressure sensor that measures the fluid pressure on the downstream side of the control valve, a flow meter that measures the flow rate of the fluid flowing through the control valve, and a control unit that controls the valve opening degree of the control valve. The control unit includes a current capacity coefficient calculation unit that calculates the capacity coefficient of the control valve as the current capacity coefficient based on the measurement values obtained from the temperature sensor, the upstream pressure sensor, the downstream pressure sensor, and the flow meter, a command capacity coefficient calculation unit that calculates the capacity coefficient obtained based on the opening degree given to the control valve as the command capacity coefficient, a comparison unit that compares the difference between the current capacity coefficient and the command capacity coefficient, and a determination unit that determines that there is an abnormality when the difference obtained by the comparison unit exceeds a predetermined value.

[0008] The current capacity coefficient is calculated from the temperature, pressure, and flow rate of the fluid flowing in the pipe and compared with the command capacity coefficient obtained based on the opening degree commanded by the control unit. When the difference (for example, the difference or ratio) between the current capacity coefficient and the command capacity coefficient becomes large, it is determined that there is deterioration due to wear of the control valve (valve body), malfunction of the positioner, control unit, etc. Since the abnormality can be determined online in this way, it is possible to arrange for spare parts at an appropriate timing, perform maintenance before a failure, and improve the operation rate. Examples of the capacity coefficient include the Cv value.

[0009] A valve device abnormality detection system according to an aspect of a reference example of the present invention includes an on-off valve provided in a pipe through which a fluid flows, a position detector that detects the open position and / or closed position of the on-off valve, and a control unit that controls the opening and closing of the on-off valve. The control unit includes a determination unit that obtains the operation time from the time when a command is given to the on-off valve to the time when the open position and / or closed position is reached by the position detector, and determines an abnormality based on the operation time.

[0010] Obtain the operating time from the time commanded by the control unit until the opening / closing valve opens / closes. Based on this operating time, it was decided to judge deterioration due to wear of the opening / closing valve (valve body) or malfunction of the control unit, etc. Since abnormalities can be judged online in this way, it becomes possible to arrange for spare parts at an appropriate timing, and maintenance before a failure becomes possible, and the operating rate can be improved.

[0011] Furthermore, in the valve device abnormality detection system according to one aspect of the reference example of the present invention, the determination unit determines that there is an abnormality when the operating time exceeds a threshold value.

[0012] If the operating time exceeds the threshold value, it is determined that the opening / closing valve has deteriorated. As the threshold value of the operating time, it is preferable to set it in advance for each type of opening / closing valve and operating environment.

[0013] Furthermore, in the valve device abnormality detection system according to one aspect of the reference example of the present invention, the control unit includes a storage unit that stores the operating time, and predicts an abnormality based on the time series of the stored operating time.

[0014] By storing the operating time, an abnormality can be predicted based on the time series.

[0015] The Reference example valve device abnormality detection system according to the present invention includes a control valve that controls the flow rate of the raw material supplied to the reaction device, a control unit that controls the control valve, a raw material flow meter that detects the flow rate of the raw material, an analyzer that analyzes the product reacted in the reaction device, and a product flow meter that detects the flow rate of the product. The control unit compares the predicted product predicted from the raw material flow meter with the current product obtained from the analyzer and the product flow meter, and determines an abnormality of the control valve or the control unit based on the difference between the predicted product and the current product.

[0016] Based on the type and flow rate of the raw materials supplied to the reaction device, predict the type and amount of the generated product. Then, based on the data obtained from the analyzer and the product flow meter, obtain the type and amount of the current product actually generated in the reaction device. By comparing the predicted product with the current product and determining the difference, it is determined whether there is deterioration due to defects in the control valve or the control unit, etc. Since abnormalities can be determined online in this way, it becomes possible to arrange spare parts at an appropriate timing, and it also becomes possible to perform maintenance before a failure, thereby improving the operation rate. Examples of the reaction device include a gasification furnace, a combustion furnace, and a cracking furnace. As the analyzer, a gas analyzer such as gas chromatography or infrared absorption spectroscopy can be used.

[0017] This According to one aspect of the invention Cooling system leakage The detection system includes a control valve for controlling the flow rate of the raw materials supplied to the reaction device, a control unit for controlling the control valve, a raw material flow meter for detecting the flow rate of the raw materials, an analyzer for analyzing the product reacted in the reaction device, and a product flow meter for detecting the flow rate of the product. The reaction device is provided with a cooling system through which cooling water flows. The control unit calculates the ratios of CO, CO2, and H2 from the current product obtained from the analyzer and the product flow meter, and based on the difference from the predicted product predicted from the raw material flow meter, determines the leakage of cooling water from the cooling system 。

[0018] When a cooling system through which cooling water flows is provided in the reaction device and a leakage occurs, the ratios of CO, CO 2 and H 2 in the product deviate from the assumed values. Based on this, it is determined whether there is a leakage in the cooling system. By stopping the plant before a fatal damage to the reaction device, the degree of damage and the repair range of the reaction device can be reduced, and the operation rate can be improved by shortening the repair period.

[0019] A method for detecting an abnormality in a valve device according to an aspect of a reference example of the present invention includes a control valve provided in a pipe through which a fluid flows, a temperature sensor that measures the temperature of the fluid flowing through the control valve, an upstream pressure sensor that measures the fluid pressure on the upstream side of the control valve, a downstream pressure sensor that measures the fluid pressure on the downstream side of the control valve, and a flow meter that measures the flow rate of the fluid flowing through the control valve. The method for detecting an abnormality in the valve device calculates the capacity coefficient of the control valve as the current capacity coefficient based on the measured values obtained from the temperature sensor, the upstream pressure sensor, the downstream pressure sensor, and the flow meter, calculates the capacity coefficient obtained based on the opening degree given to the control valve as the commanded capacity coefficient, compares the difference between the current capacity coefficient and the commanded capacity coefficient, and determines that there is an abnormality when the difference exceeds a predetermined value.

[0020] A method for detecting an abnormality in a valve device according to an aspect of a reference example of the present invention includes an on-off valve provided in a pipe through which a fluid flows and a position detector that detects the open position and / or closed position of the on-off valve. The method for detecting an abnormality in the valve device obtains the operating time from the time when a command is given to the on-off valve to the time when the open position and / or closed position is reached by the position detector, and determines an abnormality based on the operating time.

[0021] According to one aspect of the present invention Cooling system leakage The detection method is a method for detecting an abnormality in a valve device including a control valve that controls the flow rate of a raw material supplied to a reaction device, a raw material flow meter that detects the flow rate of the raw material, an analyzer that analyzes a product reacted in the reaction device, and a product flow meter that detects the flow rate of the product. The reaction device is provided with a cooling system through which cooling water flows. The control unit calculates the ratios of CO, CO2, and H2 from the current product obtained from the analyzer and the product flow meter, and based on the difference from the predicted product predicted from the raw material flow meter, determines the leakage of cooling water from the cooling system 。

Effects of the Invention

[0022] Abnormality of the valve can be easily determined online.

Brief Description of the Drawings

[0023]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Mode for Carrying Out the Invention

[0024] Hereinafter, embodiments according to the present invention will be described with reference to the drawings. [First Reference Example] Hereinafter, a first reference example of the present invention will be described. In FIG. 1, a valve device abnormality detection system 1A is shown. The valve device abnormality detection system 1A includes, in a pipe 3 through which fluid flows inside, an upstream pressure sensor 5, a temperature sensor 7, a differential pressure type flow meter 9 having an orifice 8, a flow control valve 11, and a downstream pressure sensor 13 in order from the upstream side (the left side in the figure) of the fluid flow. The valve device abnormality detection system 1A also includes a control unit 10.

[0025] The pressure PT1 is measured by the upstream pressure sensor 5, and the pressure PT2 is measured by the downstream pressure sensor 13. Also, the temperature t is measured by the temperature sensor 7. The flow control valve 11 is controlled in terms of its opening degree by the control unit 10 based on the output value of the flow meter 9.

[0026] The control unit 10 is composed of, for example, a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), and a computer-readable storage medium, etc. And a series of processes for realizing various functions are stored in a storage medium, etc. in the form of a program as an example. The CPU reads this program into the RAM, etc. and executes information processing and arithmetic operations, thereby realizing various functions. Note that the program may be in a form pre-installed in the ROM or other storage media, a form provided in a state stored in a computer-readable storage medium, a form distributed via wired or wireless communication means, etc. The computer-readable storage medium is a magnetic disk, a magneto-optical disk, a CD-ROM, a DVD-ROM, a semiconductor memory, etc.

[0027] The control unit 10 includes a current capacity coefficient calculation unit that calculates the Cv value (capacity coefficient) of the flow control valve 11 as the current Cv value based on the measurement values obtained by the respective sensors 5, 7, 13 and the flow meter 9.

[0028] The Cv value can be obtained based on the following formula.

Equation

[0029] Although the above formula is for gases, it is also defined in "ISA HANDBOOK OF CONTROL VALVES" etc. for liquids and water vapor. That is, for the fluid flow rate Q, valve inlet pressure P1, valve outlet pressure P2, and temperature t, an equation for calculating the Cv value can be obtained by referring to "ANSI / ISA-S75.01 Control Valve Sizing Equations" etc.

[0030] In the configuration shown in FIG. 1, the valve inlet pressure P1 and the valve outlet pressure P2 can be calculated as follows. P1 = PT1 - ΔP1 P2 = PT2 + ΔP2 ΔP1 ∝ λ·(l / d)·(γ / 2g)·v 2 = λ·(l / d)·(1 / 2gA 2 )·W 2 / γ ΔP2 ∝ λ·(l / d)·(γ / 2g)·v 2 = λ·(l / d)·(1 / 2g A 2 )·W 2 / γ λ: Friction coefficient (f(Re)) l: Pipe length d: Pipe diameter γ: Fluid density (kg / m3) = γ0·(T0 / TE)·(PT1 / P0) or γ0·(T0 / TE)·(PT2 / P0) v: Flow velocity in the pipe (m / s) A: Cross-sectional area of the pipe W: Mass flow rate

[0031] In the storage unit of the control unit 10, the above equations are stored, and according to the configuration of the control target, the data of λ·(l / d)·(1 / 2g A 2 ) are input in advance at the initial stage of operation. Also, for ΔP1 and ΔP2, the coefficients of the relational expressions for the flow rate and the pressure·temperature may be set according to the operation data of the plant.

[0032] The control unit 10 includes a command capacity coefficient calculation unit that calculates the Cv value as the command Cv value using the opening command value given to the flow control valve 11. The relationship between the opening command value and the Cv value is stored in the storage unit according to the type and capacity of the flow control valve 11.

[0033] The control unit 10 includes a comparison unit that compares the current Cv value and the commanded Cv value obtained as described above. In the comparison unit, the difference or ratio between the current Cv value and the commanded Cv value is calculated. In the determination unit of the control unit 10, it is determined whether the difference or ratio exceeds a threshold value. The threshold value is preset according to the type and capacity of the flow control valve 11. If the difference or ratio exceeds the threshold value, the determination unit determines that there is an abnormality. When an abnormality is determined, it is notified to the operator of the plant by display or sound.

[0034] According to this reference example, the following operational effects are achieved. The current Cv value is calculated from the temperature t of the fluid flowing in the pipe 3, the pressures P1 and P2 before and after the flow control valve 11, and the flow rate Q, and compared with the commanded Cv value obtained based on the opening degree commanded by the control unit 10. When the difference or ratio between the current Cv value and the commanded Cv value becomes larger than the threshold value, it is determined that there is deterioration due to wear of the valve body of the flow control valve 11, or failure of the positioner or the control unit 10. Since an abnormality can be determined online in this way, it becomes possible to arrange spare parts at an appropriate timing, and maintenance before failure becomes possible, and the operating rate can be improved.

[0035] As shown in FIG. 2, the same method can also be applied to a configuration in which the pressure control valve 11' is controlled based on the output of the downstream pressure sensor 13.

[0036] [Second Reference Example] Next, a second reference example of the present invention will be described. In the first reference example, a valve device abnormality detection system for the control valves 11 and 11' was described, but this reference example is a valve device abnormality detection system for on-off valves.

[0037] As shown in FIG. 3, the valve device abnormality detection system 1B includes an on-off valve 15 provided in a pipe 3 through which a fluid flows, and a control unit 17 that controls the opening and closing operation of the on-off valve 15. The on-off valve 15 is provided with a close limit switch (position detector) 19 for determining full close and an open limit switch (position detector) 20 for determining full open. The close limit switch 19 and the open limit switch 20The detection signal is transmitted to the control unit 17.

[0038] The control unit 17 includes a storage unit 17a that stores information obtained from each limit switch 19, 20, and a determination unit 17b that determines an abnormality of the on-off valve 15.

[0039] The control unit 17 detects the operation time from when a command is given to the on-off valve 15 until the limit switches 19, 20 operate. Specifically, as shown in FIG. 4, for example, when an open command is issued at time 0, it is detected that the close limit switch 19 changes from ON to OFF at the operation time T1, and it is detected that the open limit switch 20 changes from OFF to ON at the operation time T2. The control unit 17 stores the operation times T1, T2 in the storage unit 17a for each opening and closing operation of the on-off valve 15. In the following control, either of the operation times T1, T2 may be used, but preferably, the time until the open limit switch 20 becomes ON during the opening operation and the time until the close limit switch 19 becomes ON during the closing operation are used. Also, control may be performed using the difference or ratio between the operation time T1 and the operation time T2.

[0040] In the storage unit 17a of the control unit 17, relational expressions or maps such as those in FIG. 5 indicating reference values of valve operation times are stored for each valve diameter of the on-off valve 15 and for each type.

[0041] The control unit 17 obtains reference operation times T1, T2 from the map shown in FIG. 5 according to the valve diameter and type of the on-off valve 15 for which abnormality diagnosis is to be performed. Then, the determination unit 17b of the control unit 17 determines whether the operation times T1, T2 obtained from the limit switches 19, 20 exceed a threshold value. In FIG. 6, the frequency of the operation time is statistically shown. This graph is stored in the storage unit 17a and can be obtained based on the reference value of the operation time obtained from FIG. 5. The graph in FIG. 6 may be created based on data of the opening and closing operations of the past on-off valve 15. The determination unit 17b determines that there is an abnormality when the threshold value, which is the operation time exceeding a predetermined deviation statistically as shown in FIG. 6, is exceeded.

[0042] Further, as shown in FIG. 7, the control unit 17 stores the operation times T1 and T2 with respect to the number of operations of the on-off valve 15. When the number of times C1 exceeding the preset operation time is reached, it notifies that spare parts for replacement should be arranged. Further, when the number of times C2 exceeding the preset operation time is reached, it notifies to prompt replacement.

[0043] According to this reference example, the following effects are achieved. The operation times T1 and T2 from the time commanded by the control unit 17 to the opening and closing of the on-off valve 15 are obtained. Based on these operation times T1 and T2, it is decided to judge the wear of the valve body of the on-off valve 15 and the deterioration due to defects in the control unit 17 or the like. Since abnormalities can be judged online in this way, it becomes possible to arrange spare parts at an appropriate timing, and it also becomes possible to perform maintenance before a failure, and the operation rate can be improved.

[0044] Since the operation times T1 and T2 are stored in time series according to the number of opening and closing operations of the on-off valve 15, the timing for arranging spare parts and the replacement timing can be appropriately obtained.

[0045] [First Embodiment] Next, the first embodiment of the present invention will be described. This embodiment is Determine the leakage of cooling water from the cooling system as follows.

[0046] As shown in FIG. 8, various raw materials are supplied to a reaction device 21 such as a gasification furnace, a combustion furnace, and a cracking furnace. Examples of the raw materials include fuels such as coal, oxidants, and other additives. The raw materials are subjected to reactions such as gasification in the reaction device 21, and various products are generated. Examples of the products include CO, CO 2 , H 2 and CH 4 etc. in the case of a gasification furnace using coal as a fuel.

[0047] In this embodiment Cooling system leakageThe detection system 1C includes control valves 22 provided in respective channels for supplying raw materials, a control unit (not shown) for controlling these control valves 22, and a raw material flowmeter 23 for detecting the flow rate of the raw materials.

[0048] Downstream of the reaction device 21, analyzers 24(1), 24(2), 24(3) for analyzing the product and product flowmeters 25(1), 25(2), 25(3) are provided. When the product is a gas, as the analyzer 24, for example, a gas chromatograph, infrared absorption spectroscopy, etc. are used. The outputs of the analyzers 24(1), 24(2), 24(3) and the product flowmeters 25(1), 25(2), 25(3) are transmitted to the control unit.

[0049] The control unit controls the flow rate with the control valve 22, and based on the flow rate of each raw material obtained from the raw material flowmeter 23, the type and amount of the predicted product that is predicted to be generated in the reaction device 21 are calculated. This calculation may be performed by adding the results of past operations as data.

[0050] The control unit compares the predicted product obtained as described above with the type and amount of the current product obtained from the analyzer 24. Then, based on the difference between the predicted product and the current product, abnormalities in the control valve 22 and the control unit are determined.

[0051] According to this embodiment, the following operational effects are achieved. Based on the type and flow rate of the raw materials supplied to the reaction device 21, the type and amount of the generated product are predicted. Then, based on the data obtained from the analyzer 24, the type and amount of the current product actually generated in the reaction device 21 are obtained. By comparing the predicted product and the current product and determining their differences, deterioration due to defects in the control valve 22 and the control unit, etc. is determined. Since abnormalities can be determined online in this way, it becomes possible to arrange spare parts at an appropriate timing, and maintenance before a failure becomes possible, improving the operation rate.

[0052] In addition, when a cooling system through which cooling water flows is provided in the reaction apparatus 21, the leakage of the cooling system can be determined as follows.

[0053] The control unit calculates the ratios of two or more of the products CO, CO 2 , H 2 , H 2 O, and O 2 obtained from the analyzer 24 for the current products. Then, a comparison is made with the ratios of two or more of the products CO, CO 2 , H 2 , H 2 O, and O 2 for the predicted products. It is determined whether this difference is based on water (H 2 O). If it is determined that there is a close correlation with water, it is determined as a leakage from the cooling system. By stopping the plant before a fatal damage to the reaction apparatus 21, the degree of damage and the repair scope of the reaction apparatus 21 can be reduced, and the operation rate can be improved by shortening the repair period.

Explanation of Signs

[0054] 1A, 1B, 1C Valve device abnormality detection system 3 Pipe 5 Upstream pressure sensor 7 Temperature sensor 9 Flow meter 10 Control unit 11 Flow control valve 13 Downstream pressure sensor 15 On-off valve 17 Control unit 17a Storage unit 17b Judgment unit 19 Closed limit switch (position detector) 20 Open limit switch (position detector) 21 Reaction apparatus 22 Control valve 23 Raw material flow meter 24(1), 24(2), 24(3) Analyzer 25(1), 25(2), 25(3) Product flow meter

Claims

1. A control valve for controlling the flow rate of a raw material supplied to a reaction apparatus, a control unit for controlling the control valve, a raw material flow meter for detecting the flow rate of the raw material, an analyzer for analyzing a product reacted in the reaction apparatus, a product flow meter for detecting the flow rate of the product, and comprising: The reaction apparatus is provided with a cooling system through which cooling water flows, The control unit calculates the ratios of CO, CO2, and H2 from the current product obtained from the analyzer and the product flow meter, and based on the difference from the predicted product predicted from the raw material flow meter, determines leakage of cooling water from the cooling system. A cooling system leakage detection system.

2. A control valve for controlling the flow rate of a raw material supplied to a reaction apparatus, a raw material flow meter for detecting the flow rate of the raw material, an analyzer for analyzing a product reacted in the reaction apparatus, a product flow meter for detecting the flow rate of the product, A method for detecting an abnormality of a valve device of a valve device provided with: The reaction apparatus is provided with a cooling system through which cooling water flows, The ratios of CO, CO2, and H2 are calculated from the current product obtained from the analyzer and the product flow meter, and based on the difference from the predicted product predicted from the raw material flow meter, leakage of cooling water from the cooling system is determined. A cooling system leakage detection method.

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