SDI automatic determination method

Abstract

The invention relates to an SDI automatic measuring method which comprises the following steps: preparing an SDI automatic measuring instrument, and measuring by the SDI automatic measuring instrument: initially collecting time f0 of a water sample with a set volume, keeping the water sample to continuously pass through a filter membrane until set time T, collecting time ft of the water sample with the set volume again, and temperature t of the water sample, and calculating an SDI value by the SDI automatic measuring instrument, and the corrected SDI value is calculated according to the temperature of the water sample under the test. According to the SDI automatic measuring method, double precise control over the pressure in front of the film is achieved, a temperature compensation factor is introduced, dynamic compensation of testing environment interference factors is achieved, the testing precision and convenience are remarkably improved, and compared with a traditional manual testing method, the testing error reaches + / -20% in the environment with the pressure being 0.15 MPa or below; according to the method, the error can be controlled within + / -2% under the same working condition.

Description

Technical Field

[0001] The present invention relates to the technical field of water quality detection, and particularly relates to an automatic SDI determination method. Background Art

[0002] In recent years, with the continuous improvement of people's requirements for water treatment technologies, it is necessary to select appropriate water treatment technologies according to different water quality conditions to ensure the long-term stable operation of water treatment equipment.

[0003] The sludge density index (SDI) is one of the important indicators for measuring the influent water quality of water filtration equipment and is also one of the main means for testing whether the influent water quality meets the inlet requirements. Its magnitude is crucial for the operating life of water filtration equipment. It characterizes the content of particles, colloids, and other substances that can block various water filtration equipment in water. By measuring the SDI value, appropriate pretreatment can be selected to ensure the efficient operation of water filtration equipment.

[0004] However, traditional SDI meters rely on manual operation, with cumbersome test steps, high technical thresholds, large deviations in test results, and poor repeatability: manual measurement requires on-site construction of a test device, which is time-consuming and laborious; manual membrane installation, manual pressure control, and manual timing are inefficient and error-prone; manual calculation of SDI through formulas has a certain technical threshold; there are defects such as large deviations in test results without temperature calibration. Summary of the Invention

[0005] The purpose of the present invention is to provide an automatic SDI determination method that dual-precisely controls pressure, introduces a temperature compensation factor, realizes dynamic compensation for interference factors in the test environment, and significantly improves test accuracy.

[0006] To achieve the above object, the technical solution adopted by the present invention is:

[0007] An automatic SDI determination method includes:

[0008] Prepare an automatic SDI meter. Measuring by the automatic SDI meter includes: the time f0 for initially collecting a set volume of water sample, maintaining the continuous passage of the water sample through the filter membrane until the set time T, the time ft for collecting the set volume of water sample again, and the temperature t of the water sample. The automatic SDI meter calculates the SDI value:

[0009] The automatic SDI meter calculates the corrected SDI value according to the temperature of the water sample under test:

[0010] Where: η t is the hydrodynamic viscosity of water at the test water temperature, and η 25℃ is the hydrodynamic viscosity of water at 25°C water temperature.

[0011] Preferably, in the above technical solution, the SDI automatic measuring instrument pressurizes the water sample with too low water pressure in the measurement environment through a booster pump. The SDI automatic measuring instrument monitors the water pressure after pressurization in real time and adjusts the power of the booster pump according to the water pressure to achieve preliminary voltage stabilization. The automatic measuring instrument stabilizes the water pressure in front of the filter membrane at a set value through a pressure stabilizing valve, achieving dual control of the pressure in front of the membrane, and can improve the accuracy of pressure control by 5 to 10 times. Existing measuring instruments usually only rely on a pressure stabilizing valve for voltage stabilization, but the pressure behind the pressure stabilizing valve fluctuates with the pressure in front of the valve: the greater the pressure in front of the valve, the more the pressure behind the pressure stabilizing valve deviates from the preset value.

[0012] Further preferably, the SDI automatic measuring instrument includes:

[0013] Box body: There is a setting space inside the box body. An inlet and an outlet are opened on the surface of the box body, and the inlet and the outlet are communicated with the setting space;

[0014] Pipeline: The pipeline penetrates into the setting space from the inlet and penetrates out from the outlet;

[0015] Disposable filter: The disposable filter is detachably connected to the pipeline that penetrates out of the outlet;

[0016] Adaptive booster voltage stabilizing component: The adaptive booster voltage stabilizing component is connected to the pipeline in the setting space and is used for boosting and / or stabilizing the voltage of the pipeline;

[0017] Data acquisition component: The data acquisition component is connected to the pipeline in the setting space and is used for acquiring flow rate, temperature, and pressure;

[0018] Data processor: The data processor is arranged in the box body and is connected to the data acquisition component for automatically calculating the SDI value,

[0019] Through a highly integrated system design, the SDI automatic measuring instrument solves the problems of traditional equipment being not easy to carry, having cumbersome operation, and large errors, and is applicable to the assessment of the fouling risk of water filtration equipment in different scenarios, helping users estimate the service life of filter elements, optimize the maintenance cycle and system configuration.

[0020] Even more preferably, the disposable filter includes a shell and a filter membrane. There is a filtering space inside the shell. The shell has an inlet interface and an outlet interface at both ends of the filtering space. The inlet interface is detachably connected to the pipeline that penetrates out of the outlet. The filter membrane is arranged in the filtering space. The disposable filter is connected to the box body through a quick plug, which is convenient for disassembly and installation, saving time and effort.

[0021] More preferably, the filter membrane is a microfiltration membrane with a pore size of 0.45um. For example, the microfiltration membrane is a mixed cellulose ester membrane (MCE) or an equivalent hydrophilic membrane.

[0022] Even more preferably, the data acquisition component includes a flow sensor, a temperature sensor, and a pressure sensor. The flow sensor, temperature sensor, and pressure sensor are arranged on the pipeline and connected to the data processor. The flow sensor, temperature sensor, and pressure sensor are micro sensors, which are smaller and cheaper in volume compared to industrial sensors, further reducing the volume of the automatic analyzer.

[0023] More preferably, the adaptive pressurization and voltage stabilization component includes a booster pump and a pressure stabilizing valve. The booster pump is connected to the pipeline upstream of the data acquisition component, and the booster pump is connected to the data processor and / or the pressure sensor. For a measurement environment with low water pressure, the water pressure can be increased through the booster pump to meet different usage scenarios, making the automatic analyzer more universal. The data processor adjusts the output power of the booster pump according to the feedback of the pressure sensor to achieve the first-level voltage stabilization function;

[0024] The pressure stabilizing valve is connected to the pipeline downstream of the pressure sensor and is used to further stabilize the pre-membrane pressure of the disposable filter at about 0.21MPa (30psi) to achieve the second-level voltage stabilization function.

[0025] Even more preferably, the automatic analyzer further includes an operation / display panel. The operation / display panel is arranged on the outer surface of the box body and is connected to the data processor. On the one hand, the operation / display panel can guide the user to operate, and on the other hand, it can display the output result to the user, facilitating the reading of real-time data and historical records.

[0026] Even more preferably, a communication interface is configured on the data processor; the communication interface is equipped with a communication module for realizing 4G and / or WiFi communication. Through the communication interface, the measurement data can be conveniently transmitted or uploaded to the cloud platform.

[0027] Even more preferably, the automatic analyzer further includes a power supply module. The power supply module supplies power to each component in the automatic analyzer. The power supply module is a battery and / or a mains interface. The battery is arranged in the setting space, and the mains interface is arranged on the outer surface of the box body.

[0028] Even more preferably, the length of the box body is not greater than 215mm; the width is not greater than 80mm; the height is not greater than 70mm, with a small volume and convenient for carrying around.

[0029] More preferably, the total weight of the automatic measuring instrument is not greater than 1 kg, which is much lighter than similar products. The whole automatic measuring instrument is highly integrated and convenient to carry around.

[0030] Due to the application of the above technical solution, the present invention has the following advantages compared with the prior art:

[0031] The SDI automatic measurement method of the present invention enables dual-precise control of the pre-membrane pressure and introduces a temperature compensation factor to achieve dynamic compensation for interference factors in the test environment, significantly improving the test accuracy and convenience. Compared with the traditional manual test method, the test error reaches ±20% in a pressure environment below 0.15 MPa, while the present invention can control the error within ±2% under the same working conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Attached Figure 1 is a schematic diagram of the external structure of the automatic measuring instrument in the present invention;

[0033] Attached Figure 2 is a schematic diagram of the internal connection relationship of the automatic measuring instrument in the present invention;

[0034] Attached Figure 3 is a schematic diagram of the structure of the disposable filter in the present invention.

[0035] In the above drawings:

[0036] 1. Box body; 10. Water inlet; 11. Water outlet;

[0037] 2. Pipeline;

[0038] 3. Disposable filter; 30. Housing; 300. Water inlet interface; 301. Water outlet interface; 31. Filter membrane;

[0039] 40. Flow sensor; 41. Temperature sensor; 42. Pressure sensor;

[0040] 5. Data processor; 50. Operation / display panel;

[0041] 60. Booster pump; 61. Pressure stabilizing valve;

[0042] 7. Mains interface. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0043] The technical solution of the present invention will be clearly and completely described below with reference to the drawings. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of them. All other embodiments obtained by those of ordinary skill in the art without creative efforts based on the embodiments of the present invention belong to the scope of protection of the present invention.

[0044] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention. In addition, the terms "first", "second", "third" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0045] An SDI automatic measurement method includes the following steps:

[0046] First, prepare an SDI automatic measuring instrument. The following specifically gives the structure of an SDI automatic measuring instrument:

[0047] As Figure 1 、 2 shown, a portable SDI automatic measuring instrument includes a box body 1, a pipeline 2, a disposable filter 3, a data acquisition component, a data processor 5, an adaptive pressure boosting and voltage stabilizing component, a power supply module, etc. The following specifically describes each component in detail.

[0048] The box body 1 has a setting space inside, and the data acquisition component, the data processor 5, the adaptive pressure boosting and voltage stabilizing component, the power supply module, etc. are all arranged in this setting space; water inlets 10 and water outlets 11 are opened on the surface of the box body 1, and the water inlets 10 and water outlets 11 are communicated with the setting space. In the figure, the water inlets 10 and water outlets 11 are arranged at the top of the box body 1. The box body 1 is designed with an integrated shell, which is waterproof and dustproof.

[0049] In this embodiment: the length of the box body 1 is not greater than 215 mm; the width is not greater than 80 mm; the height is not greater than 70 mm. It is small in size and convenient to carry around. In the figure, the box body 1 takes 210×55×65 mm as an example.

[0050] The pipeline 2 penetrates into the setting space from the water inlet 10 and penetrates out from the water outlet 11.

[0051] The disposable filter 3 is detachably connected to the pipeline 2 passing through the water outlet 11. The disposable filter 3 can be replaced immediately after use, and the disassembly and assembly are convenient, saving time and effort. Compared with the traditional membrane pool which is reused, the membrane sheet needs to be replaced every time, and there are many steps, which also brings problems such as air exhaust. The disposable filter 3 does not have the problems of membrane replacement steps and air exhaust.

[0052] In this embodiment: as Figure 3As shown: The disposable filter 3 includes a housing 30 and a filter membrane 31. Among them: There is a filtering space inside the housing 30. At both ends of the filtering space of the housing 30, there are a water inlet interface 300 and a water outlet interface 301 respectively. The pipeline 2 passing through the water outlet 10 is detachably connected to the water inlet interface 300. For example, the two are connected through a Luer interface. That is, for the convenience of disassembling and assembling the disposable filter 3, the disposable filter 3 is located outside the box body 1. The filter membrane 31 is arranged in the filtering space. The filter membrane 31 is selected from a 0.45um microfiltration membrane, preferably an MCE mixed cellulose ester microporous filter membrane. The diameter of the housing 30 of the disposable filter 3 is about 25mm, and the inner cavity is much smaller, and there is very little air in itself. By cleaning the pipeline 2, the air bubbles in the pipeline 2 can be removed before testing.

[0053] The data acquisition component is connected to the pipeline 2 in the setting space and is used to acquire at least one of flow rate, temperature, and pressure, automatically record the flow rate, temperature, and pressure values, and send them to the data processor 5.

[0054] In this embodiment: The data acquisition component includes a flow sensor 40, a temperature sensor 41, and a pressure sensor 42. The flow sensor 40, the temperature sensor 41, and the pressure sensor 32 are arranged on the pipeline 2 and connected to the data processor 5. Among them: The flow sensor 40 is used to monitor the water flow rate, so that the amount of water collected can be directly known, saving storage and metering components such as water buckets; the temperature sensor 41 is used to monitor the water temperature, and through the water temperature, the hydrodynamic viscosity at the test water temperature can be obtained for SDI value correction; the pressure sensor 42 is used to monitor the water pressure and feedback it to the data processor 5 in real time to adjust the output power of the booster pump 60 to ensure the stability of the pressure in front of the membrane. As shown in the figure: The flow sensor 40, the temperature sensor 41, and the pressure sensor 42 are arranged in sequence along the water inlet and outlet directions of the pipeline 2. The flow sensor 40, the temperature sensor 41, and the pressure sensor 42 all adopt high-precision micro sensors, which are smaller in volume and cheaper than industrial sensors, further reducing the volume of the automatic measuring instrument.

[0055] The data processor 5 is arranged in the box body 1 and is connected to the data acquisition component. The data processor 5 configures the calculation module of the automatic measuring instrument and is configured to automatically calculate the SDI value. The data processor 5 can be customized. For example, an AI chip is integrated to achieve millisecond-level perception of the working conditions, combined with sensor data such as pressure and flow rate, to construct a high-dimensional dynamic game model for simulating the operating state of the device, and the system deep learning reinforcement learning algorithm is used to accurately control the input power of the water pump, so that the pressure in front of the disposable filter 3 reaches 30 ± 0.3 psi. Compared with the conventional pressure stabilizing valve method, the AI chip can improve the pressure control accuracy by 5 to 10 times through its AI algorithm adaptive pressure boosting and stabilizing component, achieving an accuracy jump within 1%.

[0056] Of course, as an extension of the measured data, the data processor 5 can also be configured to automatically calculate the MFI value (Modified Fouling Index) to meet different measurement requirements. The data processor 5 realizes automatic measurement through a preset program, with simple operation, and even non-professionals can quickly master it.

[0057] In an implementation manner of this embodiment: The data processor 5 is configured with an operation / display panel 50, and the operation / display panel 50 is arranged on the outer surface of the box body 1. On the one hand, the operation / display panel 50 can guide the user to operate, and on the other hand, it can display the output result to the user, facilitating the reading of real-time data and historical records. The operation / display panel 50 can adopt a touch screen, and the data processor 5 can adopt a TP-PCBA structure.

[0058] In another implementation manner of this embodiment: The data processor 5 is configured with communication interfaces, such as a 4-20mA analog signal output and an RS485 interface; the communication interfaces are equipped with communication modules for realizing 4G and / or WiFi communication. Through the communication interfaces, it is convenient to transmit the measured data or upload it to the cloud platform.

[0059] The adaptive pressurization and voltage stabilization component can ensure that there is no requirement for the inlet water pressure, and even can draw water samples on-site to complete the test. It includes a booster pump 60 and a pressure stabilizing valve 61. The booster pump 60 and the pressure stabilizing valve 61 are connected to the pipeline 2 in the setting space. The position where the booster pump 60 is connected to the pipeline 2 is upstream of the position where the data acquisition component is connected to the pipeline 2, that is, upstream of the flow sensor 40. For a measurement environment with low water pressure, the booster pump 60 can increase the water pressure to more than 0.21 Mpa (30 psi). The pressure stabilizing valve 61 is connected to the pipeline 2 between the temperature sensor 41 and the pressure sensor 42, and the pressure stabilizing valve 61 is used to stabilize the pre-membrane pressure of the disposable filter 3 at about 0.21 MPa (30 psi).

[0060] The power supply module supplies power to each component in the automatic measuring instrument. The power supply module is a battery and / or a mains interface 7. The battery can adopt a lithium battery and is arranged in the setting space. The mains interface 7 is arranged on the outer surface of the box body 1 for connecting the mains, and two methods are available for selection.

[0061] The overall weight of the automatic measuring instrument in this embodiment is not greater than 1 kg, which is much lighter than similar products. The entire automatic measuring instrument is highly integrated and convenient to carry around.

[0062] The following specifically elaborates on the process of automatic measurement using the SDI automatic measuring instrument of this embodiment.

[0063] Before the test, first clean the pipeline 2 to discharge the air in the pipeline 2, and then connect the disposable filter 3 to the quick connector of the pipeline 2 that penetrates the water outlet 10;

[0064] Start the SDI automatic measuring instrument, and measure through the data processor 5 of the SDI automatic measuring instrument, including:

[0065] The time f0 for initially collecting a set volume of water sample, keeping the water sample continuously passing through the filter membrane until the set time T, the time ft for collecting the set volume of water sample again, and the temperature t of the water sample.

[0066] The data processor 5 calculates the SDI value:

[0067] After introducing temperature calibration, the influence of environmental factors (0°C to 55°C) on the test results is eliminated, thereby improving the measurement accuracy. The data processor 5 calculates the corrected SDI value according to the temperature of the water sample under test:

[0068]

[0069] Where: η t is the hydrodynamic viscosity at the test water temperature, and η 25℃ is the hydrodynamic viscosity at 25°C water temperature.

[0070] In this embodiment: It includes dual pressure control, a dual control system composed of a pressure negative feedback to control the power of the booster pump and a pressure stabilizing valve, to achieve the dynamic stability of the pressure before the membrane at 0.207 ± 0.002 Mpa (30 ± 0.3 psi).

[0071] Embodiment:

[0072] The following uses the automatic measuring instrument of this embodiment to perform automatic SDI measurement on water sources 1 - 5.

[0073] Filter membrane: MCE microfiltration membrane; Test conditions: 20 ± 0.2°C; The influent is tap water; Pressure 0.207 ± 0.007 Mpa.

[0074] Water source SDI <![CDATA[SDI 测试值 > Error Water source 1 3.01 3.07 2％ Water source 2 4.22 4.3 2％ Water source 3 5.11 5.05 -1.2％ Water source 4 5.61 5.6 -0.2％ Water source 5 6.25 6.25 0％

[0075] Compared with the existing SDI tester, the test error can reach ±20% in a pressure environment below 0.15 Mpa. Under the same working conditions, the device of the present invention can control the error within ±2%.

[0076] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable those familiar with this technology to understand the content of the present invention and implement it accordingly, and cannot be used to limit the protection scope of the present invention. All equivalent changes or modifications made according to the spirit and essence of the present invention should be covered within the protection scope of the present invention.

Claims

1. An automatic SDI measurement method, characterized in that: Including: Prepare an SDI automatic measuring instrument, and measure through the SDI automatic measuring instrument including: The time f0 for initially collecting a set volume of water sample, keeping the water sample continuously passing through the filter membrane until the set time T, the time ft for collecting the set volume of water sample again, and the temperature t of the water sample. The SDI automatic measuring instrument calculates the SDI value: The SDI automatic measuring instrument calculates the corrected SDI value according to the temperature of the water sample under test: Where: η t is the hydrodynamic viscosity at the test water temperature, and η 25℃ is the hydrodynamic viscosity at a water temperature of 25°C.

2. The SDI automatic measurement method according to claim 1, characterized in that: The SDI automatic measuring instrument pressurizes the water sample with too low water pressure in the measurement environment through a booster pump. The SDI automatic measuring instrument monitors the water pressure after pressurization in real time and adjusts the power of the booster pump according to the water pressure; the automatic measuring instrument stabilizes the water pressure in front of the filter membrane at a set value through a pressure stabilizing valve.

3. The SDI automatic measurement method according to claim 1, characterized in that: The SDI automatic measuring instrument includes: a box body: there is a setting space inside the box body, and a water inlet and a water outlet are opened on the surface of the box body, and the water inlet and the water outlet are communicated with the setting space; A pipeline: the pipeline penetrates into the setting space from the water inlet and penetrates out from the water outlet; A disposable filter: the disposable filter is detachably connected to the pipeline penetrating out of the water outlet; An adaptive pressurization and pressure stabilizing component: the adaptive pressurization and pressure stabilizing component is connected to the pipeline in the setting space for pressurizing and / or stabilizing the pipeline; A data acquisition component: the data acquisition component is connected to the pipeline in the setting space for acquiring flow rate, temperature, and pressure; A data processor: the data processor is arranged in the box body and is connected to the adaptive pressurization and pressure stabilizing component and the data acquisition component for automatically calculating the SDI value.

4. The SDI automatic measurement method according to claim 3, wherein: The disposable filter includes a housing and a filter membrane. There is a filtering space inside the housing. The housing has a water inlet interface and a water outlet interface at both ends of the filtering space. The water inlet interface is detachably connected to the pipeline penetrating out of the water outlet, and the filter membrane is arranged in the filtering space.

5. The SDI automatic measurement method according to claim 3, characterized in that: The data acquisition component includes a flow sensor, a temperature sensor, and a pressure sensor. The flow sensor, the temperature sensor, and the pressure sensor are arranged on the pipeline and are connected to the data processor.

6. The SDI automatic measurement method according to claim 5, wherein: The adaptive pressurization and pressure stabilizing component includes a booster pump and a pressure stabilizing valve. The booster pump is connected to the pipeline upstream of the data acquisition component, and the booster pump is connected to the data processor and / or the pressure sensor; the pressure stabilizing valve is connected to the pipeline downstream of the pressure sensor.

7. The SDI automatic measurement method according to claim 3, characterized in that: The automatic measuring instrument further includes an operation / display panel. The operation / display panel is arranged on the outer surface of the box body and is connected to the data processor.

8. The SDI automatic measurement method according to claim 3, characterized in that: A communication interface is configured on the data processor, and the communication interface is equipped with a communication module for realizing 4G and / or WiFi communication.

9. The SDI automatic measurement method according to claim 3, wherein: The automatic measuring instrument further includes a power supply module. The power supply module supplies power to each component in the automatic measuring instrument. The power supply module is a battery and / or a mains interface. The battery is arranged in the setting space, and the mains interface is arranged on the outer surface of the box body.

10. The SDI automatic measurement method according to claim 3, characterized in that: The length of the box body is not greater than 215 mm; the width is not greater than 80 mm; the height is not greater than 70 mm; The total weight of the described automatic measuring instrument is not greater than 1 kg.

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