Reverse osmosis membrane group conductivity value automatic cycle detection method and system

Abstract

The invention relates to the technical field of reverse osmosis seawater desalination monitoring, and discloses a reverse osmosis membrane module conductivity value automatic cycle detection method and system, the reverse osmosis membrane module conductivity value automatic cycle detection method specifically comprises the following steps: receiving a high pressure pump operation signal, and only starting a detection program in a high pressure pump operation state; enabling the detected media at the plurality of membrane shell sampling points and the energy recovery device sampling points to sequentially enter a conductivity meter according to a preset sequence; performing data reading on the sampling points, comparing the measured conductance values of the sampling points with an alarm threshold value, and triggering alarm when the measured conductance values exceed the threshold value; and after detection of all sampling points is completed, automatic cyclic detection is carried out again. According to the invention, multi-point automatic monitoring can be realized, and performance abnormity of the membrane module can be found in time.

Description

Technical Field

[0001] The present invention relates to the technical field of reverse osmosis seawater desalination monitoring, in particular to a method and system for automatically circulating the conductivity value of a reverse osmosis membrane group. Background Art

[0002] Reverse osmosis (RO) desalination is a widely used desalination technology. The performance of its core component, the RO membrane, has a decisive impact on the water quality and energy consumption of the entire system. Large-scale desalination projects typically employ multiple RO membrane modules, each containing numerous membrane shell units and energy recovery devices.

[0003] Traditional reverse osmosis membrane module monitoring methods primarily rely on monitoring the total output water conductivity of the module to determine whether any of the 168 membrane shells in the module have exceeded the conductivity standard. If the conductivity exceeds the standard significantly, operators must manually collect effluent samples from each membrane shell and then measure the conductivity using a portable conductivity meter. Only when the energy recovery unit stops operating will operators manually collect effluent samples from each energy recovery unit for monitoring. However, this method has several drawbacks. First, the gradual increase in conductivity of individual membrane shells cannot be monitored in real time. Individual assessments are only performed when the total output water conductivity exceeds the standard, making it difficult to detect abnormal membrane module performance in a timely manner. Second, due to the large number of membrane shells, the monitoring workload is heavy, and measurement results from different operators over time lack consistency, making it difficult to generate reliable historical data for trend analysis.

[0004] Therefore, it is urgent to propose a method and system for automatically circulating the conductivity value of a reverse osmosis membrane group to solve the above problems. Summary of the Invention

[0005] The purpose of the present invention is to provide a method and system for automatic circulation detection of the conductivity value of a reverse osmosis membrane group, which can realize multi-point automatic monitoring and timely detect abnormal performance of the membrane group.

[0006] In order to solve the above technical problems, the present invention provides a method for automatically circulating the conductivity value of a reverse osmosis membrane group, which specifically includes the following steps:

[0007] Receive the high-pressure pump operation signal and start the detection program only when the high-pressure pump is in operation;

[0008] The detected media at multiple membrane shell sampling points and energy recovery device sampling points are sequentially fed into the conductivity meter in a preset order;

[0009] Reading data from the sampling point, comparing the measured conductivity value of the sampling point with the alarm threshold, and triggering an alarm when the threshold is exceeded; and

[0010] After completing the detection of all sampling points, the detection will automatically re-circulate.

[0011] Furthermore, the step of allowing the detected media at multiple sampling points to enter the conductivity meter in sequence according to a preset order is achieved by controlling the switching valve group.

[0012] Furthermore, the data reading at the sampling point specifically includes: first performing pipeline flushing and then performing data reading to obtain the conductivity value.

[0013] Furthermore, the pipeline flushing lasts for a first preset time; and the data reading lasts for a second preset time.

[0014] Furthermore, the alarm threshold is dynamically adjusted according to the membrane module operation time and historical data.

[0015] Furthermore, it also includes real-time display of the current measured sampling point position and the corresponding conductivity value through the interface.

[0016] Furthermore, it also includes generating conductivity trend data for evaluating changes in membrane group performance.

[0017] In addition, the present invention also provides a reverse osmosis membrane group conductance value automatic circulation detection system for implementing the reverse osmosis membrane group conductance value automatic circulation detection method as described above, comprising:

[0018] A control system for receiving high-pressure pump operation signals and controlling the detection process;

[0019] Conductivity meter, used to measure the conductivity value of the medium being tested;

[0020] An electric switching valve group is used to select the sampling points for current detection according to a preset sequence; and

[0021] The sampling pipe network is used to connect multiple membrane housing sampling points and energy recovery device sampling points to the conductivity meter.

[0022] Furthermore, it also includes a display unit for displaying the conductance value and system status, as well as displaying the location of the sampling point currently being measured and the corresponding conductance value.

[0023] Furthermore, the control system is a PLC control system having a data processing function for filtering abnormal conductance values and generating a conductance value trend curve.

[0024] Through the above technical solution, the present invention has the following beneficial effects:

[0025] By only initiating the test program when the high-pressure pump is operating and sequentially feeding the test medium from multiple membrane housing and energy recovery device sampling points into the same conductivity meter in a pre-set sequence, automated conductivity monitoring is achieved during actual system operation. This method avoids the cost and calibration issues associated with multiple conductivity meters while ensuring comprehensive coverage of all membrane housings and energy recovery devices, effectively addressing the low frequency and incomplete coverage of traditional manual inspections. This cyclical testing mechanism ensures continuous monitoring and timely detection of membrane module performance anomalies, providing a reliable basis for operational and maintenance decisions.

[0026] Furthermore, data reading after pipeline flushing improves measurement accuracy. Dynamically adjusted alarm thresholds take into account membrane module operating time and historical data, adapting to the changing characteristics of membrane performance at different stages. The generation of conductivity trend data provides a scientific basis for membrane module performance evaluation. Furthermore, the PLC control system's data processing capabilities and intuitive display interface significantly enhance the system's intelligent operation and maintenance, reducing maintenance costs and extending the life of the membrane modules. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 Flowchart of a method for automatically circulating the conductivity value of a reverse osmosis membrane group according to one embodiment of the present invention;

[0028] Figure 2 Schematic diagram of the structure of the automatic circulation detection system for the conductivity value of the reverse osmosis membrane group in one embodiment of the present invention. DETAILED DESCRIPTION

[0029] The following is a more detailed description of a method and system for automatically cycling conductivity detection of a reverse osmosis membrane assembly according to the present invention, with reference to the accompanying drawings. Preferred embodiments of the present invention are shown. It should be understood that those skilled in the art may modify the present invention described herein while still achieving the beneficial effects of the present invention. Therefore, the following description should be understood as generally known to those skilled in the art and is not intended to limit the present invention.

[0030] The following paragraphs describe the present invention in more detail by way of example with reference to the accompanying drawings. The advantages and features of the present invention will become more apparent from the following description. It should be noted that the drawings are greatly simplified and not to exact scale, and are provided solely for the purpose of assisting in the description of the embodiments of the present invention.

[0031] like Figure 1 As shown, the embodiment of the present invention provides a method for automatically circulating the conductivity value of a reverse osmosis membrane group, which specifically includes the following steps:

[0032] S1, receiving the high-pressure pump operation signal, and starting the detection program only when the high-pressure pump is running;

[0033] S2. Allow the detected media at multiple membrane shell sampling points and energy recovery device sampling points to enter the conductivity meter in sequence according to a preset order;

[0034] S3, reading data from the sampling point, comparing the measured conductivity value of the sampling point with the alarm threshold, and triggering an alarm when the threshold is exceeded; and

[0035] S4. After completing the detection of all sampling points, the detection will be automatically re-circulated.

[0036] This implementation can avoid meaningless detection when the system is not in operation, thereby improving detection efficiency and data validity.

[0037] Preferably, the step of sequentially allowing the tested medium at multiple sampling points to enter the conductivity meter in a predetermined order is achieved by controlling a switching valve assembly. In one specific example, the switching valve assembly includes multiple electric ball valves, each connected to a corresponding sampling point. By programmatically controlling the opening and closing sequence of these electric ball valves, the tested medium enters the conductivity meter in a predetermined order. Using a switching valve assembly to control the flow path can reduce the number of conductivity meters required, lowering system costs and reducing calibration and maintenance workload.

[0038] In one embodiment, reading data from a sampling point specifically includes first flushing the pipeline and then reading the data to obtain the conductance value. Specifically, flushing the pipeline means allowing the sample liquid at the current sampling point to flow through the pipeline for a period of time before officially measuring the conductance value to remove any remaining sample liquid. This flush-before-reading approach enhances the accuracy and representativeness of the measured data and avoids measurement errors caused by retained liquid in the pipeline.

[0039] In this embodiment, the pipeline flushing lasts for a first preset time, and the data reading lasts for a second preset time. In one specific example, the first preset time is 30 seconds, and the second preset time is also 30 seconds. Those skilled in the art will appreciate that these time parameters can be adjusted based on factors such as the actual system's pipeline length, flow rate, and sample liquid characteristics, and include other embodiments besides this one. Appropriate flushing and reading time settings improve measurement reliability while avoiding unnecessary waste of resources.

[0040] Preferably, the alarm threshold is dynamically adjusted based on the membrane module's operating time and historical data. Specifically, the system can automatically adjust the alarm threshold based on factors such as the module's operating time, historical conductivity value trends, and seasonal factors. For example, a lower alarm threshold can be set during the initial operation of a new membrane. As operating time increases, the system will appropriately increase the threshold based on the gradual upward trend of actual conductivity values. This dynamic adjustment mechanism can enhance the rationality and effectiveness of alarms and reduce false alarms.

[0041] In one embodiment, the present invention further includes a real-time display of the current measured sampling point location and corresponding conductance value via an interface. Specifically, the interface is a touchscreen graphical interface that displays information such as the currently measured sampling point number, location, real-time conductance value, and historical data curves. This intuitive real-time display function enhances the visualization of system operating status, allowing operators to quickly understand system operation status.

[0042] This embodiment also generates conductance trend data for evaluating membrane module performance changes. Specifically, the system regularly saves conductance data for each sampling point, generates trend charts, and calculates indicators such as the conductance change rate. This trend data can be used to assess membrane module performance degradation, predict membrane element lifespan, and facilitate the development of effective membrane cleaning or replacement plans. The conductance trend analysis function enhances the system's predictive maintenance capabilities, extends the lifespan of the membrane module, and reduces maintenance costs.

[0043] In addition, if Figure 2 As shown, this embodiment also proposes a reverse osmosis membrane group conductivity value automatic circulation detection system for implementing the reverse osmosis membrane group conductivity value automatic circulation detection method as described above, including: a control system for receiving a high-pressure pump operation signal and controlling the detection process; a conductivity meter for measuring the conductivity value of the detected medium; an electric switching valve group for selecting the sampling point currently being detected in a preset order; and a sampling pipe network for connecting multiple membrane shell sampling points and energy recovery device sampling points to the conductivity meter.

[0044] In one embodiment, the control system is a PLC control system. Specifically, the PLC control system includes a central processing unit, input / output modules, a communication module, and a storage module. The PLC system is responsible for controlling the switching sequence of the electric switching valve group according to a preset program, receiving data from the conductivity meter, and performing data processing and alarm determination functions. The PLC control system includes a data processing function for filtering abnormal conductivity values and generating a conductivity trend curve. In one specific example, the data processing function includes an outlier filtering algorithm that can identify and filter out abnormal measurement values caused by transient equipment failures or external interference, thereby improving the accuracy and reliability of data analysis.

[0045] Preferably, this embodiment also includes a display unit for displaying the conductance value and system status, as well as the location of the currently measured sampling point and the corresponding conductance value. Specifically, the display unit can be a 10-inch industrial-grade touch screen developed using human-machine interface software. The interface design includes a system overview page, a real-time monitoring page, a historical trend page, and a system settings page. The system overview page graphically displays the entire reverse osmosis system structure and current operating status; the real-time monitoring page displays the location of the currently measured sampling point and the real-time conductance value; the historical trend page displays the conductivity value trend of each sampling point in the form of a curve; and the system settings page is used for parameter setting and system maintenance. This intuitive display interface enhances the system's usability and maintainability, improving operational management efficiency.

[0046] In this embodiment, the electric switching valve assembly consists of multiple electric ball valves, each corresponding to a sampling point. Specifically, the electric ball valves are powered by a 24V DC power supply and driven by a PLC control system via a relay module. All electric ball valves are closed by default and only open when the corresponding sampling point is required for testing. This embodiment improves system reliability and safety by avoiding pressure fluctuations and measurement errors caused by the simultaneous activation of multiple sampling points.

[0047] In one embodiment, the sampling pipe network adopts food-grade PP pipes with good corrosion resistance and sealing properties. Specifically, the sampling pipe network connects the multiple membrane shell sampling points of the reverse osmosis membrane group and the energy recovery device sampling points to the electric switching valve group through pipelines, and then the electric switching valve group is connected to the conductivity meter. In a specific example, the diameter of the sampling pipe network is 8 mm, and the length of the pipeline is determined according to the on-site installation position, but the residence time of the fluid in the pipe must be considered to ensure that the flushing time is set reasonably. It is known to those skilled in the art that the pipe diameter can be set according to actual needs, and also includes other embodiments besides this embodiment. A reasonably designed sampling pipe network improves the reliability and stability of sample liquid transmission and ensures the accuracy of measurement data.

[0048] In this embodiment, the conductivity meter is an online conductivity meter with a range of 0-20,000 μS / cm and an accuracy of ±0.5% FS. Specifically, the conductivity meter is installed at the end of the sampling pipe network and utilizes a flow-through measuring cell to ensure continuous flow of the measured medium. The conductivity meter communicates with the PLC control system via a signal line, transmitting measurement data in real time. The high-precision conductivity meter, combined with the flow-through measuring cell design, improves the accuracy and response speed of conductivity measurements.

[0049] Preferably, the system's pipeline flushing and data reading time can be set through the touch screen interface. Specifically, the system presets a flushing time of 30 seconds and a data reading time of 30 seconds, but the operator can adjust it within a range of 10 to 60 seconds according to actual needs. Those skilled in the art will appreciate that these time parameters can be set according to actual needs and include other embodiments besides this embodiment. The flexible parameter setting function enhances the adaptability and versatility of the system, making it applicable to reverse osmosis systems of different sizes and types.

[0050] In this embodiment, the system first detects the high-pressure pump's operating signal. Once the high-pressure pump is confirmed to be running, the PLC control system initiates the detection process according to a preset program. The detection process begins at the first sampling point. The control system issues a command to open the corresponding electric ball valve, allowing the sample liquid at that sampling point to flow through the sampling pipe network to the conductivity meter. The system first flushes the pipes. After the flushing time expires, it begins reading the data. After the reading time expires, the system compares the read conductivity value with the set alarm threshold. If the threshold is exceeded, an alarm is triggered. Subsequently, the current ball valve closes, and the ball valve for the next sampling point opens, repeating the flushing, reading, and comparison process. When all sampling points have been tested, the system automatically begins a new round of cyclic testing.

[0051] In summary, the method and system for automatically circulating the conductivity value of a reverse osmosis membrane group proposed in the present invention have the following advantages:

[0052] By only initiating the test program when the high-pressure pump is operating and sequentially feeding the test medium from multiple membrane housing and energy recovery device sampling points into the same conductivity meter in a pre-set sequence, automated conductivity monitoring is achieved during actual system operation. This method avoids the cost and calibration issues associated with multiple conductivity meters while ensuring comprehensive coverage of all membrane housings and energy recovery devices, effectively addressing the low frequency and incomplete coverage of traditional manual inspections. This cyclical testing mechanism ensures continuous monitoring and timely detection of membrane module performance anomalies, providing a reliable basis for operational and maintenance decisions.

[0053] Furthermore, data reading after pipeline flushing improves measurement accuracy. Dynamically adjusted alarm thresholds take into account membrane module operating time and historical data, adapting to the changing characteristics of membrane performance at different stages. The generation of conductivity trend data provides a scientific basis for membrane module performance evaluation. Furthermore, the PLC control system's data processing capabilities and intuitive display interface significantly enhance the system's intelligent operation and maintenance, reducing maintenance costs and extending the life of the membrane modules.

[0054] Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if such changes and modifications fall within the scope of the claims and their equivalents, the present invention is intended to include such changes and modifications.

Claims

1. A method for automatically circulating the conductivity value of a reverse osmosis membrane group, characterized in that: The details include: Receive the high-pressure pump operation signal and start the detection program only when the high-pressure pump is in operation; The detected media at multiple membrane shell sampling points and energy recovery device sampling points are sequentially fed into the conductivity meter in a preset order; The data of the sampling points are read, and the conductivity value of the measured sampling points is compared with the alarm threshold. When the threshold is exceeded, an alarm is triggered; and after completing the detection of all sampling points, the detection is automatically re-circulated.

2. The method for automatically circulating the conductivity value of a reverse osmosis membrane group according to claim 1, wherein: The step of allowing the detected media at multiple sampling points to enter the conductivity meter in sequence according to a preset order is achieved by controlling the switching valve group.

3. The method for automatically circulating the conductivity value of a reverse osmosis membrane group according to claim 1, wherein: The data reading at the sampling point specifically includes: first performing pipeline flushing and then performing data reading to obtain the conductivity value.

4. The method for automatically circulating the conductivity value of a reverse osmosis membrane group according to claim 3, wherein: The pipeline flushing lasts for a first preset time; and the data reading lasts for a second preset time.

5. The method for automatically circulating the conductivity value of a reverse osmosis membrane group according to claim 3, wherein: The alarm threshold is dynamically adjusted according to the membrane group operation time and historical data.

6. The method for automatically circulating the conductance value of a reverse osmosis membrane group according to claim 1, wherein: It also includes real-time display of the current measured sampling point position and the corresponding conductivity value through the interface.

7. The method for automatically circulating the conductance value of a reverse osmosis membrane group according to claim 1, wherein: It also includes the generation of conductivity trend data for evaluating changes in membrane performance.

8. A reverse osmosis membrane group conductance value automatic circulation detection system, used to implement the reverse osmosis membrane group conductance value automatic circulation detection method according to any one of claims 1 to 7, characterized in that: include: A control system for receiving high-pressure pump operation signals and controlling the detection process; Conductivity meter, used to measure the conductivity value of the medium being tested; The electric switching valve group is used to select the sampling points for current detection according to the preset order; as well as The sampling pipe network is used to connect multiple membrane housing sampling points and energy recovery device sampling points to the conductivity meter.

9. The automatic circulation detection system for the conductance value of a reverse osmosis membrane group according to claim 8, characterized in that: It also includes a display unit for displaying the conductivity value and system status, as well as displaying the location of the sampling point currently being measured and the corresponding conductivity value.

10. The automatic circulation detection system for the conductance value of a reverse osmosis membrane group according to claim 8, characterized in that: The control system is a PLC control system having a data processing function for filtering abnormal conductance values and generating a conductance value trend curve.

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