A two-stage cyclone functionalized membrane environmental sample enrichment detection system

Abstract

The application discloses a two-stage cyclone functional membrane environmental sample enrichment detection system, and relates to the technical field of environmental monitoring. The system comprises a box body, a sample inlet unit, a two-stage cyclone separation unit, a membrane enrichment unit, a monitoring execution unit and a control unit which are arranged in the box body or connected with the box body. The sample inlet unit is used for guiding the environmental sample into the system. The two-stage cyclone separation unit comprises a primary cyclone and a secondary cyclone which are connected in series, is used for discharging large particles and medium particles impurities in the sample through underflow under the centrifugal action, and makes the overflow containing target objects to be transported backward. The membrane enrichment unit comprises a membrane assembly with an embedded functional membrane, is used for receiving the overflow of the secondary cyclone and enriching the target objects. The application avoids the non-specific adsorption and loss of the target objects from the physical space link, and reduces the blocking load of the subsequent membrane assembly.

Description

Technical Field

[0001] This invention relates to the field of environmental monitoring technology, specifically to a two-stage swirl-functionalized membrane environmental sample enrichment and detection system. Background Technology

[0002] With increasingly stringent requirements for ecological and environmental monitoring, the precise enrichment and detection of trace target substances in environmental samples (such as natural water bodies and wastewater), including environmental DNA (eDNA), microplastics, persistent organic pollutants, and antibiotic resistance genes, has become increasingly important. Functionalized membranes, due to their synergistic effect of physical retention and chemical adsorption, have become a key means to achieve efficient enrichment of target substances.

[0003] However, the above-mentioned technologies still have the following drawbacks: the matrix of real-world environmental samples is usually extremely complex, containing a large amount of suspended impurities such as silt, microalgae, and colloids. In existing membrane enrichment detection systems, if environmental samples are introduced directly or only after simple coarse filtration into the membrane module, severe membrane fouling (such as local pore blockage and membrane surface accumulation) can easily and rapidly occur, leading to a sharp drop in system permeate flux, a surge in operating pressure differential, and even irreversible damage to the membrane material.

[0004] To mitigate membrane fouling, existing technologies typically incorporate settling or multi-stage filtration. However, these traditional pretreatment methods are not only inefficient and prone to trapping and losing target particles, but also generally suffer from high hardware redundancy and complex piping structures, making it difficult to achieve non-invasive dynamic sensing and intelligent linkage adjustment of real-time flow path anomalies and membrane fouling conditions. When dealing with complex water samples such as those with high turbidity and high algae content, existing equipment struggles to strike a balance between "efficient impurity removal" and "stable target particle retention," frequently resulting in forced shutdowns due to blockages, affecting the continuity and accuracy of environmental sample enrichment detection. Summary of the Invention

[0005] The purpose of this invention is to provide a two-stage swirling functionalized membrane environmental sample enrichment and detection system to solve the technical problems existing in the prior art.

[0006] The technical problem to be solved by the present invention can be achieved by the following technical solution: a two-stage cyclone functionalized membrane environmental sample enrichment and detection system, comprising a sample introduction unit, a two-stage cyclone separation unit, a membrane enrichment unit, a monitoring and execution unit, and a control unit; The sample introduction unit is used to introduce environmental samples into the system. The two-stage hydrocyclone separation unit includes a first-stage hydrocyclone and a second-stage hydrocyclone connected in series, which are used to discharge large and medium-sized particulate impurities in the sample through the underflow under centrifugal force, and to transport the overflow containing the target analyte backward. The membrane enrichment unit includes a membrane assembly with a built-in functional membrane for receiving the overflow from the secondary hydrocyclone and enriching the target analyte; The monitoring and execution unit is used to collect the injection flow rate, pre-membrane flow rate, pre-membrane pressure, and post-membrane pressure, and to perform pump and valve regulation; The control unit is used to control the process of environmental sample injection, two-stage hydrocyclone separation, membrane enrichment, and liquid discharge.

[0007] Preferably, the sample introduction unit includes a sampling tube with an anti-clogging nozzle, a sampling tube interface, a quick connector, and a primary pump connected in sequence. The outlet end of the primary pump is connected to the primary hydrocyclone.

[0008] Preferably, the two-stage cyclone separation unit further includes a secondary pump, an overflow collection pipe, and an underflow drainage pipe. The overflow outlet of the primary cyclone separator is connected to the secondary cyclone separator via the overflow collection pipe, and the underflow outlets of both cyclones are connected to the underflow drainage pipe. The membrane enrichment unit also includes a three-stage pump, an inlet, and a drain pipe. The overflow outlet of the secondary hydrocyclone is connected to the inlet of the membrane module, and the liquid outlet of the membrane module is connected to the drain pipe.

[0009] Preferably, the monitoring and execution unit includes a flow meter, a pressure gauge, a flow and pressure sensor, and a pneumatic valve; The control unit acquires the baseline initial flow rate and initial differential pressure after the system starts up, and calculates the average flow rate and flow fluctuation coefficient within a specified time window during operation.

[0010] Preferably, the control process of the control unit is as follows: Based on the underflow discharge ratio, flow fluctuation coefficient and differential pressure rise rate of the benchmark sampling section, the water sample type is determined according to the preset hierarchical discrimination rules and the corresponding control parameters are called from the parameter configuration table. Based on the collected flow rate and pressure, a target retention index and a membrane fouling risk index are constructed. The membrane fouling status is determined according to the priority order of local flow path anomaly, pore blockage, and surface accumulation. Based on this, the monitoring execution unit is adjusted in a coordinated manner to maintain the stable enrichment of the target. The process of obtaining the target retention index is as follows: the ratio of real-time membrane pre-flow to injection flow, the complementary terms of flow fluctuation, and the complementary terms of the ratio of underflow discharge flow to injection flow are assigned preset weights and then summed.

[0011] Preferably, the control unit calculates the pressure difference between the membrane and the membrane and its rate of increase in real time; The membrane fouling risk index is obtained by summing the real-time pressure difference growth ratio relative to the initial pressure difference, the pressure difference increase rate, and the membrane inlet flow rate decrease ratio relative to the initial membrane inlet flow rate, each with a preset weight.

[0012] Preferably, the determination process of the control unit is as follows: If the flow fluctuation coefficient exceeds the standard and the pressure difference jumps, it is determined to be a local flow path abnormality; If the flow path is normal, but the membrane fouling risk index exceeds the standard, the pressure difference continues to rise, and the flow rate before the membrane drops significantly, it is determined to be pore blockage. If the flow path is normal and not blocked, but the membrane fouling risk index exceeds the standard, the pressure difference continues to rise, and the flow rate in front of the membrane decreases slightly, it is judged as surface accumulation.

[0013] Preferably, the linkage adjustment process of the control unit is as follows: When surface accumulation occurs, keep the speed of the first and second stage pumps basically unchanged, reduce the speed of the third stage pump and drive the pneumatic valve to perform short-cycle pulse unloading. When the channel is blocked, simultaneously reduce the speed of the secondary and tertiary pumps and increase the unloading opening of the pneumatic valve; When there is a local flow path abnormality, reduce the speed of the primary pump to a low level and adjust the opening and closing frequency of the pneumatic valve to release the stagnant fluid.

[0014] Preferably, the hierarchical discrimination rule is: When α ≥ 0.35 and γ ≥ γ h At that time, it was identified as a complex water sample with high sediment and high algae content; When α ≥ 0.35 and γ < γ h At that time, the water sample was identified as a high-sediment type. When α < 0.35 and β ≥ 0.20 and γ ≥ γ h At that time, it was identified as a high-algae colloidal water sample; If none of the above conditions are met, the sample is classified as a conventional water sample. Where α is the underflow discharge ratio, β is the flow fluctuation coefficient, and γ is the pressure difference rise rate. h For the high threshold of the rate of increase of differential pressure, γ h = 3 × γ0, where γ0 is the average differential pressure rise rate within the reference sampling segment.

[0015] Preferably, the control unit generates target pump speeds for the primary pump, secondary pump, and tertiary pump, respectively: The target pump speed of the primary pump is: N 1,k+1 = N 1,k +C 1,1 ×(I M,lim - I M,k )-C 1,2×(α k -α ref ); The target pump speed of the secondary pump is: N 2,k+1 = N 2,k +C 2,1 ×(I T,ref - I T,k )+C 2,2 ×(α k -α ref ); The target pump speed of the three-stage pump is: N 3,k+1 = N 3,k +C 3,1 ×(I T,ref - I T,k )-C 3,2 ×(I M,k - I M,lim ); Where, N 1,k N 2,k N 3,k These represent the target pump speeds for the primary, secondary, and tertiary pumps in the current control cycle, respectively, N. 1,k+1 N 2,k+1 N 3,k+1 These are the target pump speeds for the primary, secondary, and tertiary pumps in the next control cycle, respectively. T,k To retain the index for the target, I T,ref Reserve the exponential setpoint for the target, I M,k I is the membrane fouling risk index. M,lim α is the upper limit of membrane fouling risk. k α represents the underflow discharge ratio. ref Set the target underflow discharge ratio, C 1,1 C 1,2 C 2,1 C 2,2 C 3,1 C 3,2 This is the adjustment coefficient.

[0016] Compared with the prior art, the beneficial effects of this application are as follows: 1. This invention achieves efficient and load-reducing separation of complex sample matrices by constructing a two-stage hydrocyclone separation unit comprising a primary hydrocyclone and a secondary hydrocyclone. This system, without disrupting fluid continuity, utilizes a centrifugal field to sequentially separate and discharge large particles of sediment and medium-sized flocs that are prone to clogging through the underflow, while simultaneously ensuring that trace amounts of environmental DNA, microplastics, and other micro-targets enter the membrane module to the maximum extent possible with the overflow. Compared to traditional static sedimentation or multi-stage filtration, this invention avoids non-specific adsorption and loss of target substances from a physical spatial perspective, while also reducing the clogging load on subsequent membrane modules.

[0017] 2. This invention, by extracting only basic pipeline flow and differential pressure signals from the control unit, can accurately identify abnormal states of different dimensions, such as local flow path anomalies, channel blockages, and surface accumulation, without changing the existing fluid physical topology or adding additional complex detection probes. This mechanism deeply integrates algorithm features with industrial fluid characterization, effectively reducing the hardware redundancy of the system and providing a reliable data base for adaptive control. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of the housing in the two-stage cyclone functionalized membrane environmental sample enrichment and detection system of the present invention; Figure 2 This is a schematic diagram of the sampling tube structure in a two-stage swirling functionalized membrane environmental sample enrichment and detection system of the present invention; Figure 3 This is a schematic diagram of the internal structure of the chamber in the two-stage swirl-functionalized membrane environmental sample enrichment and detection system of the present invention; Figure 4 This is a schematic diagram of the pneumatic valve in a two-stage swirl-functionalized membrane environmental sample enrichment and detection system of the present invention; Figure 5 This is a schematic diagram of the membrane module in a two-stage swirling functionalized membrane environmental sample enrichment and detection system of the present invention.

[0019] Explanation of reference numerals in the attached figures: 1. Sampling tube interface; 2. Sampling tube; 3. Anti-clogging head; 4. Drain pipe; 5. Drain outlet; 6. Control panel; 7. Primary pump; 8. Secondary pump; 9. Tertiary pump; 10. Flow meter; 11. Pressure gauge; 12. Function compartment; 13. Power supply compartment; 14. Quick connector; 15. Flow and pressure sensor; 16. Pneumatic valve; 17. Overflow collection pipe; 18. Primary hydrocyclone; 19. Underflow drainage pipe; 20. Secondary hydrocyclone; 21. Membrane module; 22. Inlet. Detailed Implementation

[0020] The specific embodiments of the present invention will be described in detail below, but it should be understood that the scope of protection of the present invention is not limited to the specific embodiments.

[0021] Example 1 In existing membrane enrichment detection systems, if environmental samples are introduced directly or after only simple coarse filtration into the membrane module, it is very easy to quickly cause serious membrane fouling (such as local pore blockage and membrane surface accumulation).

[0022] like Figures 1 to 5In this embodiment, a two-stage cyclone functionalized membrane environmental sample enrichment and detection system includes a housing and a sample introduction unit, a two-stage cyclone separation unit, a membrane enrichment unit, a monitoring and execution unit, and a control unit disposed in or connected to the housing. In this embodiment, the sample introduction unit is used to introduce environmental samples into the system; The two-stage hydrocyclone separation unit includes a first-stage hydrocyclone 18 and a second-stage hydrocyclone 20 connected in series, which are used to discharge large and medium-sized particulate impurities in the sample through the underflow under centrifugal action and to transport the overflow containing the target analyte backward. The membrane enrichment unit includes a membrane assembly 21 with a built-in functional membrane for receiving the overflow from the secondary cyclone separator 20 and enriching the target analyte. The monitoring and execution unit is used to collect the injection flow rate, pre-membrane flow rate, pre-membrane pressure, and post-membrane pressure, and to perform pump and valve regulation; The control unit is used to control the process of environmental sample injection, two-stage hydrocyclone separation, membrane enrichment, and liquid discharge.

[0023] The working principle of this embodiment is as follows: Figures 1-5 In this embodiment, the environmental sample is first introduced into the system through the sample introduction unit. After being introduced into the system, the sample passes through a series of first-stage hydrocyclones 18 and second-stage hydrocyclones 20. Under centrifugal action, the first-stage hydrocyclones 18 and second-stage hydrocyclones 20 can discharge large and medium-sized particulate impurities in the sample through the underflow, and the overflow containing the target analyte is transported backward to the membrane enrichment unit. The membrane module 21 built into the membrane enrichment unit receives the overflow from the second-stage hydrocyclone 20 and enriches the target analyte. Throughout the process, the sample introduction flow rate, pre-membrane flow rate, pre-membrane pressure, and post-membrane pressure can be collected by the monitoring and execution unit, and the pump valve can be adjusted. Based on the monitoring results, the environmental sample introduction, two-stage hydrocyclone separation, membrane enrichment, and drainage process can be controlled by the control unit.

[0024] It should be emphasized that the core improvement of this embodiment lies in the following: This embodiment achieves efficient and load reduction of complex sample matrices by constructing a two-stage hydrocyclone separation unit including a first-stage hydrocyclone 18 and a second-stage hydrocyclone 20. Without disrupting fluid continuity, the system can use a centrifugal field to sequentially separate and discharge large particles of silt and medium-sized particles that are prone to clogging through the underflow. At the same time, it ensures that trace targets such as environmental DNA and microplastics enter the membrane module 21 to the maximum extent with the overflow. Compared with traditional static sedimentation or multi-stage filter interception, it avoids non-specific adsorption and loss of targets from the physical spatial link, and reduces the clogging load of the subsequent membrane module 21. Meanwhile, throughout the process, the monitoring and execution unit and the control unit work together to control the sample injection, two-stage hydrocyclone separation, membrane enrichment and drainage process of environmental samples to ensure the stability of the system.

[0025] It should be noted that, such as Figures 2-5 As shown, the housing includes a functional compartment 12 and a power supply compartment 13. The functional compartment 12 is equipped with a sampling tube interface 1 and a drain outlet 5. Specifically, it includes a sampling tube interface 1, a sampling tube 2, an anti-clogging head 3, a quick connector 14, and a primary pump 7. The sampling tube interface 1 is connected to the sampling tube 2. The sampling tube 2 is equipped with an anti-clogging head 3 at its inlet end. The sampling tube interface 1 is connected to the inlet end of the primary pump 7 via the quick connector 14. This is used to introduce environmental samples into the functional compartment 12 and establish the initial sample loading of the environmental samples into the system. As one embodiment of this example, the two-stage cyclone separation unit further includes an overflow collection pipe 17, an underflow drainage pipe 19, and a secondary pump 8. The outlet end of the primary pump 7 is connected to the inlet end of the primary cyclone separator 18. The overflow outlet of the primary cyclone separator 18 is connected to the inlet end of the secondary cyclone separator 20 via the overflow collection pipe 17. The secondary pump 8 is installed on the overflow collection pipe 17. The underflow outlet of the primary cyclone separator 18 is connected to the drain outlet 5 via the underflow drainage pipe 19. The underflow outlet of the secondary cyclone separator 20 is connected to the drain outlet 5 via the underflow drainage pipe 19. It should be noted that in this embodiment, the first-stage hydrocyclone 18 is used to remove large particulate suspended impurities from the environmental sample under the action of a centrifugal field, and the second-stage hydrocyclone 20 is used to remove medium particulate suspended impurities from the overflow of the first-stage hydrocyclone 18 under the action of a centrifugal field, so that the target material can continue to be transported backward with the overflow.

[0026] Furthermore, the membrane enrichment unit also includes an inlet 22, a drain pipe 4, and a tertiary pump 9. The overflow outlet of the secondary hydrocyclone 20 is connected to the inlet 22 of the membrane module 21. The tertiary pump 9 is installed on the pipe of the overflow outlet of the secondary hydrocyclone 20. The liquid outlet of the membrane module 21 is connected to the drain outlet 5 via the drain pipe 4. Specifically, the membrane module 21 includes a functional membrane disposed within the membrane housing. The functional membrane is a physical retention membrane, a chemical adsorption membrane, or a retention-adsorption composite membrane, used to enrich the target substances in the environmental sample overflowing from the secondary hydrocyclone 20. It should be noted that the membrane module 21 in this embodiment is used to enrich one or more of the following in the environmental sample onto the functional membrane through pore size retention, electrostatic adsorption, hydrophobic interaction, or the synergistic effect of two or more mechanisms: environmental DNA, microplastics or nanoplastics, persistent organic pollutants, pharmaceuticals and personal care products, antibiotic resistance gene carriers, and colloidal particles.

[0027] In this embodiment, the monitoring and execution unit includes a primary pump 7, a secondary pump 8, a tertiary pump 9, a flow meter 10, a pressure gauge 11, a flow and pressure sensor 15, and a pneumatic valve 16. The flow meter 10, pressure gauge 11, and flow and pressure sensor 15 are used to collect flow signals, pressure signals, and differential pressure change signals during the environmental sample enrichment detection process. The primary pump 7, secondary pump 8, tertiary pump 9, and pneumatic valve 16 are used to perform sample injection adjustment, two-stage cyclone transition transport adjustment, membrane pre-driving force adjustment, and flow path on / off adjustment according to control commands.

[0028] For details, please refer to Figures 2-4 In this embodiment, the pneumatic valve 16 is a three-way valve. Its inlet end is connected to the pipeline between the secondary hydrocyclone 20 and the tertiary pump 9, its first outlet end is connected to the inlet 22 of the membrane module 21, and its second outlet end is connected to the drain pipe 4. By controlling the opening degree and opening and closing frequency of the pneumatic valve 16, the flow rate entering the membrane module 21 can be adjusted.

[0029] It should be noted that the control unit in this embodiment is the control panel 6. The control panel 6 is located in the function compartment 12 and is electrically connected to the primary pump 7, the secondary pump 8, the tertiary pump 9, the flow and pressure sensor 15, and the pneumatic valve 16 respectively. In one embodiment, the control panel 6 includes a controller, a memory, a data acquisition module, and a drive module. The memory stores a control program, a parameter configuration table, and historical operation records. The data acquisition module is connected to a flow meter 10, a pressure gauge 11, and a flow and pressure sensor 15, respectively, to receive real-time operation data during the environmental sample enrichment detection process. The drive module is connected to a primary pump 7, a secondary pump 8, a tertiary pump 9, and a pneumatic valve 16, respectively, to execute the adjustment commands output by the controller.

[0030] It should be noted that when the control program of this embodiment is running, it is executed in a cyclical manner in the order of signal acquisition, data verification, index calculation, state discrimination, pump and valve linkage and result writing back, so that the first-stage hydrocyclone 18, the second-stage hydrocyclone 20 and the membrane module 21 maintain a synergistic balance between target retention and membrane antifouling in the same operation.

[0031] It should be emphasized that the working process of this embodiment is as follows: The external environment sample first enters the sampling tube 2 through the anti-clogging head 3, and then enters the functional chamber 12 through the sampling tube interface 1 and quick connector 14. It is then transported to the inlet end of the first-stage hydrocyclone 18 under the drive of the first-stage pump 7. After the environmental sample enters the first-stage hydrocyclone 18, a rotating flow field is formed under the action of the centrifugal field. Large suspended impurities with larger particle size, higher density, or those that are prone to clogging migrate along the outer periphery to the underflow side and enter the underflow drainage pipe 19 through the underflow outlet of the first-stage hydrocyclone 18, and are finally discharged through the drain outlet 5. Correspondingly, the first-stage overflow water containing the target substance flows out from the overflow outlet of the first-stage hydrocyclone 18 and enters the sample inlet of the second-stage hydrocyclone 20 through the overflow collection pipe 17. The primary overflow water continues to form a rotating flow field after entering the secondary hydrocyclone 20. Medium-sized suspended impurities, fine flocs, and some particulate components that are prone to membrane fouling that the primary hydrocyclone 18 failed to remove accumulate along the underflow side in the secondary hydrocyclone 20 and enter the underflow drainage pipe 19 through the underflow outlet of the secondary hydrocyclone 20 and are discharged from the drain outlet 5. The secondary overflow water that is retained after secondary separation in the secondary hydrocyclone 20 flows out from the overflow outlet of the secondary hydrocyclone 20 and enters the inlet 22 of the membrane module 21. After the secondary overflow water enters the membrane module 21, it comes into contact with the functional membrane inside the membrane module 21. The target substances in the environmental sample are enriched on the surface or inside the functional membrane through pore size interception, electrostatic adsorption, hydrophobic interaction, or a combination of two or more mechanisms. The remaining liquid that is not enriched flows out from the outlet end of the membrane module 21 and is transported to the drain outlet 5 through the drain pipe 4 for discharge. Based on this, the system in this embodiment can remove large particulate suspended impurities first, then medium particulate suspended impurities, and finally achieve the enrichment of the target material on the membrane module 21 without changing the basic structural link.

[0032] Example 2 It is understandable that, in Example 1, the existing technology is unable to achieve non-invasive dynamic sensing and intelligent linkage adjustment of real-time flow path anomalies and membrane fouling conditions.

[0033] Based on this, the control process of the control unit in this embodiment is as follows: Based on the underflow discharge ratio, flow fluctuation coefficient and differential pressure rise rate of the benchmark sampling section, the water sample type is determined according to the preset hierarchical discrimination rules and the corresponding control parameters are called from the parameter configuration table. Based on the collected flow rate and pressure, a target retention index and a membrane fouling risk index are constructed. The membrane fouling status is determined according to the priority order of local flow path anomaly, pore blockage, and surface accumulation. Based on this, the monitoring execution unit is adjusted in a coordinated manner to maintain the stable enrichment of the target. The control unit is also equipped with a parameter self-tuning module, which is used to update the weight coefficients and thresholds in the parameter configuration table online based on the results of each run.

[0034] In this embodiment, the acquisition location and acquisition method of variables in the acquisition module are defined as follows: The system injection flow rate is collected by flow meter 10 on the main injection pipeline between the outlet of primary pump 7 and the inlet of primary hydrocyclone 18, and is used as the system injection flow rate for the k-th sampling period. The pre-membrane flow rate and pre-membrane pressure are collected by flow and pressure sensor 15 on the pre-membrane branch between the overflow outlet of secondary hydrocyclone 20 and the inlet 22 of membrane module 21, and are used as the pre-membrane flow rate and pre-membrane pressure for the k-th sampling period, respectively. The post-membrane pressure is collected by pressure gauge 11 on the post-membrane branch between the outlet of membrane module 21 and the drain pipe 4, and is used as the post-membrane pressure for the k-th sampling period. Since the underflow from primary hydrocyclone 18 and secondary hydrocyclone 20 eventually flows into drain outlet 5 through underflow drain pipe 19, and the change in stagnant volume during the stable operation phase of the system is negligible, the underflow discharge flow rate for the k-th sampling period is obtained by subtracting the pre-membrane flow rate from the system injection flow rate. Thus, all flow and pressure variables used in the control program can be found in the existing structural entity with clear sources and do not depend on additional hardware units.

[0035] To ensure a unified benchmark for subsequent judgments, the controller first executes a benchmark sampling segment after system startup. The benchmark sampling segment begins timing when the liquid column in sampling tube 2 is stable and the primary hydrocyclone 18, secondary hydrocyclone 20, and membrane module 21 are all in a continuous outflow state. In one embodiment, the benchmark sampling segment length can be 20 seconds, and the sampling period can be 2 seconds, thus generating 10 sets of initial sampling values. The controller averages the system inlet flow rate, pre-membrane flow rate, pre-membrane pressure, and post-membrane pressure within this benchmark sampling segment to obtain the initial system inlet flow rate, initial pre-membrane flow rate, initial pre-membrane pressure, and initial post-membrane pressure. Based on this, an initial pressure difference is generated. This initial value serves as the benchmark for subsequent normalization processing and threshold mapping, and is also written into the historical operation record for parameter retrieval for subsequent similar water samples.

[0036] Within a control cycle, the controller first averages the real-time flow sequence within the judgment window to obtain the window average flow:

[0037] in, Let be the average flow rate of the window at the k-th decision time. Let b be the real-time flow rate value of the i-th sampling period, and b be the number of sampling points in the judgment window. The average flow rate of the window is used to characterize the flow rate baseline level of the current judgment window. In one embodiment, b can be 15, corresponding to a judgment window of 30 seconds.

[0038] The controller then calculates the flow fluctuation coefficient based on the deviation between the real-time flow value in the k-th sampling period and the average flow rate within the window.

[0039] in, Let be the flow fluctuation coefficient at the k-th judgment time. The real-time flow rate value for the kth sampling period. The average flow rate at the k-th judgment time is the flow rate of the window. The flow rate fluctuation coefficient is used to characterize the stability of the current flow path. The larger the value, the more obvious the flow rate fluctuation.

[0040] It should be noted that, in order to reduce the impact of occasional noise, the controller in this embodiment performs median filtering on the flow rate values ​​within three consecutive sampling periods. If the deviation of the current sample value from the previous sample value exceeds 30%, and the subsequent sample value returns to the normal range, the current sample value is determined to be an abnormal sample value and is removed, and replaced with the average of two adjacent normal sample values.

[0041] The controller calculates the pressure rise rate based on the membrane pressure in adjacent sampling periods:

[0042] in, Let k be the rate of pressure increase at the k-th judgment time. The membrane pressure during the k-th sampling period is... Δt represents the membrane pressure in the previous sampling period, and Δt represents the time interval between adjacent sampling periods. The pressure rise rate is used to characterize the growth trend of the load at the front end of membrane module 21.

[0043] The controller then calculates the real-time pressure difference based on the inlet and outlet pressures, and further calculates the rate of increase of the pressure difference:

[0044] in, The real-time pressure difference during the k-th sampling period. The membrane pressure during the k-th sampling period is... The pressure behind the membrane during the kth sampling period is denoted as .

[0045]

[0046] in, Let K be the rate of increase of the pressure difference at the k-th judgment time. The real-time pressure difference during the k-th sampling period. Δt represents the real-time pressure difference of the previous sampling period, and Δt represents the time interval between adjacent sampling periods. The pressure difference and the rate of increase of the pressure difference are used together to characterize the rate of pollution development of membrane module 21 under the current control parameters.

[0047] After identifying the sources of flow and pressure variables, the controller constructs a target retention index. This index characterizes the overall degree to which, under the current control parameters, clogging particles are discharged via the underflow while the target material still enters the membrane module 21 with the overflow. The calculation method is as follows:

[0048] in, The exponent is retained for the target at the k-th decision time. The membrane inlet flow rate is the flow rate during the kth sampling period. Let W1 be the system injection flow rate for the kth sampling period, and W2 and W3 be weighting coefficients that satisfy W1 + W2 + W3 = 1. In this embodiment, the underflow discharge flow rate is determined by the following formula:

[0049] in, The underflow discharge rate is the value of the k-th sampling period. Let be the system injection flow rate for the k-th sampling period. For the membrane inlet flow rate in the kth sampling period, a mass conservation relationship based on the steady-state operation phase is defined to obtain the executable underflow discharge rate without adding an additional underflow flow meter.

[0050] The controller synchronously constructs a membrane fouling risk index, which characterizes the comprehensive risk of surface buildup, pore blockage, or localized flow path anomalies in membrane module 21. The calculation method is as follows:

[0051] in, This represents the membrane fouling risk index at the k-th judgment time. The real-time pressure difference during the k-th sampling period. The initial pressure difference obtained from the reference sampling section. Let K be the rate of increase of the pressure difference at the k-th judgment time. The membrane inlet flow rate is the flow rate during the kth sampling period. V1, V2, and V3 are the initial flow rates obtained from the baseline sampling section, and V1, V2, and V3 are weighting coefficients that satisfy V1 + V2 + V3 = 1. The larger the target retention index, the higher the degree to which the target material enters the membrane module 21 with the overflow. The larger the membrane fouling risk index, the closer the membrane module 21 is to a state that is not conducive to continuous enrichment operation.

[0052] To avoid a lack of basis for setting weighting coefficients and thresholds, the controller determines the water sample type and calls the corresponding parameter configuration according to the following steps after the baseline sampling segment ends: S100, Determine the reference parameters; Specifically, the controller calculates the following three characteristic parameters based on the reference sampling segment: Underflow discharge ratio α=Q u,0 / Q in,0 , where Q u,0Q represents the average underflow discharge rate within the baseline sampling section. in,0 The average system injection flow rate within the baseline sampling segment; Flow fluctuation coefficient β=K Q,0 , where K Q,0 The average flow fluctuation coefficient within the reference sampling segment; The rate of increase of pressure difference γ=R ΔP,O , where R ΔP,O The average rate of increase of differential pressure within the reference sampling segment S200, water sample type identification; Specifically, the controller determines the water sample type according to the following hierarchical rules: When α ≥ 0.35 and γ ≥ γ h When the water sample is identified as a complex type of water with high sediment and high algae colloid content, the corresponding weight configuration is applied: W1=0.40, W2=0.20, W3=0.40; V1=0.50, V2=0.25, V3=0.25. When α ≥ 0.35 and γ < γ h When the water sample is identified as high sediment type, the corresponding weight configuration is applied: W1=0.35, W2=0.15, W3=0.50; V1=0.55, V2=0.25, V3=0.20; When α < 0.35 and β ≥ 0.20 and γ ≥ γ h When the sample is identified as a high-algae colloidal water sample, the corresponding weighting is applied: W1=0.45, W2=0.25, W3=0.30; V1=0.45, V2=0.25, V3=0.30. If none of the above conditions are met, the water sample is classified as a conventional water sample, and the corresponding weight configuration is applied: W1=0.40, W2=0.20, W3=0.40; V1=0.50, V2=0.20, V3=0.30. Where, γ h γ is the highest threshold for the rate of increase of differential pressure. h =3×γ0, where γ0 is the average differential pressure rise rate within the reference sampling segment; It should be noted that the above values ​​in this embodiment are used to illustrate the parameter generation method and are not limited to a unique value; the core is to establish the parameter source through the benchmark sampling segment and to achieve clear and mutually exclusive classification of water sample types through hierarchical discrimination rules, so that a clear mapping relationship is formed between the control parameters and the sample types.

[0053] After obtaining the target retention index and membrane fouling risk index, the controller performs membrane fouling status discrimination according to a fixed priority. The priority is set as follows: first, discern the abnormal state of the local flow path; then, discern the pore blockage state; and finally, discern the surface accumulation state.

[0054] The reason for adopting this priority is that local flow path abnormalities can cause sudden changes in flow rate and pressure. If these are not eliminated first, it will affect the accuracy of subsequent identification of pore blockage and surface deposits. Pore blockage poses a higher risk of damage to the functional membrane of membrane module 21 than surface deposits. Therefore, pore blockage is identified first when local flow path abnormalities are not met. Surface deposits, as a relatively slow contamination state, are identified only when neither of the first two conditions is met.

[0055] Specifically, when the flow fluctuation coefficient is greater than 0.25 for two consecutive judgment windows, and the pressure before the membrane or the real-time differential pressure jumps by more than 20% above the average value of the previous window, it is judged as a local flow path abnormality. When the local flow path abnormality is not established, and the membrane fouling risk index exceeds the membrane fouling risk upper limit for two consecutive judgment windows, while the pressure rise rate and differential pressure rise rate are continuously positive, and the decrease in the flow rate before the membrane relative to the initial flow rate before the membrane exceeds 15%, it is judged as a pore blockage state. When neither the local flow path abnormality state nor the pore blockage state is established, but the membrane fouling risk index exceeds the membrane fouling risk upper limit for two consecutive judgment windows, the differential pressure rise rate is continuously positive, and the decrease in the flow rate before the membrane relative to the initial flow rate before the membrane is less than 15%, it is judged as a surface accumulation state. If none of the above conditions are met, the membrane module 21 is judged to be in a stable enrichment state.

[0056] To ensure that the control actions strictly correspond to the existing structural entities, this embodiment maps the control functions of the three pumps as follows: The primary pump 7 is used to adjust the total injection load of environmental samples into the primary hydrocyclone 18, and its output changes directly affect the system injection flow rate. The secondary pump 8 is used to adjust the transition conveying intensity between the primary hydrocyclone 18 and the secondary hydrocyclone 20. Its output change directly affects the connection stability between the two hydrocyclones. The three-stage pump 9 is used to adjust the in-membrane driving force entering the membrane module 21, and its output changes directly affect the in-membrane flow rate and in-membrane pressure. Based on this mapping relationship, the controller performs differentiated adjustments to different pumps under different membrane fouling conditions, rather than performing homogeneous control on the three-stage pump.

[0057] As one implementation method of this embodiment, the controller independently calculates the target pump speeds of the primary pump 7, the secondary pump 8, and the tertiary pump 9, specifically as follows: The primary pump 7 is used to control the total injection load, and its target pump speed is mainly adjusted based on the membrane fouling risk index and the underflow discharge ratio. N 1,k+1 = N 1,k +C 1,1 ×(I M,lim - I M,k )-C 1,2 ×(α k -αref ) Where, N 1,k For the target pump speed of primary pump 7 in the current control cycle, N 1,k+1 To achieve the target pump speed for primary pump 7 in the next control cycle, I M,k Let I be the membrane fouling risk index for the k-th judgment period. M,lim α is the upper limit of membrane fouling risk. k Let α be the underflow discharge ratio at the k-th judgment time. ref Set the target underflow discharge ratio, C 1,1 and C 1,2 To adjust the coefficient, the core logic of this embodiment is: reduce the injection load when the risk of membrane fouling increases, and increase the injection load to enhance the cyclone separation effect when the underflow is insufficient; Secondary pump 8 is used to control the transition delivery intensity between the two-stage vortex flow. Its target pump speed is mainly adjusted based on the target retention index and the underflow discharge ratio. N 2,k+1 = N 2,k +C 2,1 ×(I T,ref - I T,k )+C 2,2 ×(α k -α ref ) Where, N 2,k N is the target pump speed of the secondary pump in the current control cycle. 2,k+1 For the target pump speed of secondary pump 8 in the next control cycle, I T,k I is the target retention index for the k-th judgment period. T,ref To retain the target exponential setpoint, α k Let α be the underflow discharge ratio at the k-th judgment time. ref Set the target underflow discharge ratio, C 2,1 and C 2,2 As for the adjustment coefficient, the core logic of this embodiment is: when the target retention index is too low, increase the transition conveying intensity to increase the overflow rate; when the underflow discharge ratio is too high, appropriately enhance the conveying to balance the two-stage vortex load. The three-stage pump 9 is used to control the pre-membrane driving force entering the membrane module 21, and its target pump speed is adjusted based on the combined target retention index and membrane fouling risk index. N 3,k+1 = N 3,k +C 3,1 ×(I T,ref - I T,k )-C 3,2 ×(I M,k - I M,lim ) Where, N 3,kFor the target pump speed of the three-stage pump in the current control cycle, N 3,k+1 For the target pump speed of the third-stage pump 9 in the next control cycle, C 3,1 and C 3,2 To adjust the coefficient, the core logic of this embodiment is: to increase the driving force before the membrane to increase the membrane flux when the target retention is insufficient, and to reduce the driving force to slow down the development of pollution when the membrane fouling risk exceeds the standard.

[0058] It should be emphasized that the adjustment coefficients for each pump in this embodiment are configured as follows: For primary pump 7, the target retention term adjustment coefficient is 0, the pollution risk term adjustment coefficient is 0.12, the underflow proportion term adjustment coefficient is 0.06, and the maximum single adjustment range is 5%. For secondary pump 8, the target retention term adjustment coefficient is 0.08, the pollution risk term adjustment coefficient is 0, the underflow proportion term adjustment coefficient is 0.05, and the maximum single adjustment range is 5%. For the three-stage pump 9, the adjustment coefficient for the target retention item is 0.10, the adjustment coefficient for the pollution risk item is 0.08, the adjustment coefficient for the underflow ratio item is 0, and the maximum adjustment range per operation is 8%.

[0059] It should be noted that the above values ​​in this embodiment are used to illustrate the parameter generation method and are not limited to a unique value. The single pump speed adjustment range is limited to 3% to 8% of the current pump speed to prevent over-adjustment.

[0060] The controller synchronously generates the target valve opening for the next control cycle:

[0061] Among them, A k+1 For the target valve opening in the next control cycle, A k The target valve opening is the valve opening degree for the current control cycle. d1 and d2 are valve opening adjustment coefficients. The single valve opening adjustment range is limited to 2% to 6% of the full opening. The target valve opening degree is used to adjust the opening and closing rhythm of pneumatic valve 16 and the branch flow distribution.

[0062] It should be noted that, under surface buildup conditions, the controller maintains the target pump speeds of the primary pump 7 and the secondary pump 8 unchanged or makes only minor adjustments of no more than 3%, while lowering the target pump speed of the tertiary pump 9 by one adjustment step and driving the pneumatic valve 16 to perform short-cycle pulse unloading; in a data-driven example, the pulse unloading cycle can be 6 seconds, and the duration of a single unloading can be 0.8 seconds. The purpose of this control action is to weaken the deposited layer on the membrane surface without disrupting the continuity of the two-stage swirling separation. When the duct is blocked, the controller synchronously reduces the target pump speed of the secondary pump 8 and the tertiary pump 9, and increases the unloading opening of the pneumatic valve 16 by one opening step to reduce the continuous pressure differential entering the membrane module 21; in a data example, the secondary pump 8 and the tertiary pump 9 can be reduced by 5% and 8% respectively, and the opening of the pneumatic valve 16 can be increased by 5%; In the event of a localized flow path anomaly, the controller first switches the primary pump 7 to a low-speed maintenance state to reduce the total injection load. Then, it adjusts the opening and closing rhythm of the pneumatic valve 16 according to a predetermined sequence to release stagnant fluid. Subsequently, it determines whether to restore the original target values ​​of the secondary pump 8 and the tertiary pump 9 based on whether the flow fluctuation coefficient returns to normal. All of the above actions are achieved using the existing primary pump 7, secondary pump 8, tertiary pump 9, and pneumatic valve 16, without requiring any additional actuators.

[0063] To enhance the system's feasibility under abnormal operating conditions, this embodiment further sets up anomaly tolerance rules. If the flow meter 10, pressure gauge 11, or flow and pressure sensor 15 outputs a value exceeding the device's range in any sampling period, the sampled value is marked as invalid. If an invalid value occurs only once, the controller replaces it with the previous valid sampled value. If an invalid value occurs three times consecutively, the controller determines that the corresponding sensor link is abnormal and enters a degraded control mode.

[0064] In the degraded control mode, primary pump 7, secondary pump 8, and tertiary pump 9 all revert to the safe pump speed corresponding to the baseline sampling segment. Pneumatic valve 16 switches to the preset safe opening. The system only maintains low-load venting and no longer performs active regulation driven by the target retention index and membrane fouling risk index. If the controller does not observe changes in flow rate or pressure response corresponding to the target pump speed or target valve opening within two sampling cycles after outputting the regulation command, it is presumed that the execution is inadequate. When inadequate execution occurs twice consecutively, the controller outputs a protection command, stops tertiary pump 9, and shuts down the corresponding high-load branch to prevent membrane module 21 from continuing to bear high pressure differential under unknown conditions.

[0065] To ensure a clear endpoint for the control process, this embodiment sets up normal termination rules and abnormal termination rules. Normal termination rules include any of the following: reaching a preset sample processing volume; reaching a preset enrichment runtime; or the target retention index changing by no more than 5% for three consecutive judgment windows, and the membrane fouling risk index not exceeding the membrane fouling risk upper limit, indicating that the current operation has reached the stable enrichment endpoint. Abnormal termination rules include any of the following: the membrane fouling risk index exceeding the membrane fouling risk upper limit for three consecutive judgment windows and failing to decrease after two rounds of pump-valve linkage adjustment; continuous abnormalities in the sensor link and the degraded control mode persisting for more than a preset duration; or continuous abnormalities in the local flow path without being resolved. Regardless of whether the termination is normal or abnormal, the controller performs a unified closing action: first, stop the tertiary pump 9, then stop the secondary pump 8, and finally stop the primary pump 7; during the pump shutdown process, keep the pneumatic valve 16 in the venting opening position so that the remaining liquid in the functional chamber 12 is discharged through the drain pipe 4 and the drain outlet 5; after the closing is completed, write the target retention index trajectory, membrane fouling risk index trajectory, membrane fouling status judgment result and termination reason of this operation into the historical operation record for subsequent use of similar water samples.

[0066] It should be emphasized that in this embodiment, the target retention index I... T,k The three weights W1, W2, and W3 in the algorithm are determined using the analytic hierarchy process (AHP). The specific steps are as follows: Construct the judgment matrix A = [a ij ]3×3, where a ij The i-th indicator is assigned a value relative to the j-th indicator using a 1-9 scale. The eigenvector corresponding to the largest eigenvalue of the judgment matrix is ​​calculated and normalized to become the weight vector. A consistency check is performed to ensure that the consistency ratio CR is less than 0.1.

[0067] Among them, the elements of the judgment matrix are assigned different values ​​for different water sample types. Specifically, in high sediment water samples, the "complementary term of bottom flow discharge ratio" (corresponding to W3) is given higher importance; in high algae colloidal water samples, the "complementary term of flow fluctuation degree" (corresponding to W2) is given higher importance; and in conventional water samples, the importance of the three indicators is basically balanced.

[0068] It should be further noted that, in this embodiment, the upper limit of membrane fouling risk I is... M,lim The determination method is as follows: Under laboratory conditions, a constant pressure fouling test is conducted on the target functional membrane; the critical pressure difference ΔPcrit when the membrane flux drops to 70% of the initial flux is recorded; the membrane fouling risk index value corresponding to ΔPcrit is taken as I. M,lim For functional membranes with different materials and pore sizes, I M,lim The specific values ​​were determined by those skilled in the art through the above experiments; The weight coefficients and thresholds in the parameter configuration table were obtained through orthogonal experiments conducted under laboratory conditions using at least 50 valid samples from each of the typical water samples (high sediment type, high algae colloid type, high sediment and high algae colloid composite type, and conventional type). The dual optimization objectives were "target analyte recovery rate greater than or equal to 85%" and "continuous operation time greater than or equal to 120 minutes," optimized via grid search. Taking the high sediment water sample configuration as an example, the parameter combinations satisfying the dual optimization objectives were selected by traversing the search space where W1 ranges from 0.2 to 0.5, W2 from 0.1 to 0.3, and W3 from 0.3 to 0.6, with a step size of 0.05.

[0069] Control panel 6 also features a manual parameter input interface, allowing operators to directly modify the weight coefficients and thresholds in the parameter configuration table based on on-site experience or laboratory analysis results, thus achieving flexible human-machine collaborative control.

[0070] Based on this, through the above-described enhanced control implementation method, the variable acquisition location, index construction method, parameter source, state boundary, discrimination order, pump function mapping, fault tolerance rules, and control termination rules have all formed a complete closed loop. Those skilled in the art, without altering the structural entity defined in Embodiment 1, can achieve coordinated control of the first-stage hydrocyclone 18, the second-stage hydrocyclone 20, and the membrane module 21 solely based on the existing connection relationships of the control panel 6, flow meter 10, pressure gauge 11, flow and pressure sensor 15, first-stage pump 7, second-stage pump 8, third-stage pump 9, and pneumatic valve 16. This allows the system to simultaneously consider target analyte retention, membrane operational stability, and the accuracy of enrichment detection results under complex environmental sample conditions. The numerical values ​​given in the above embodiments are only used to illustrate the feasible implementation of the control logic and do not constitute a limitation on the scope of protection.

[0071] The above formulas are all dimensionless numerical calculations. The weighting coefficients and judgment thresholds in the above formulas can be preset by those skilled in the art through a limited number of routine experiments or based on experience, depending on the specific application scenario and water quality conditions. The core of this application lies in constructing the target retention index and membrane fouling risk index through a specific combination of flow rate and pressure variables, and calling the corresponding parameter configuration according to the water sample type, thereby realizing the classification and linkage adjustment of membrane fouling status. The preset parameters and thresholds in the formulas are set by those skilled in the art according to the actual situation, and this application is not limited to specific values.

[0072] Those skilled in the art will recognize that the modules and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0073] The basic principles, main features, and advantages of this application have been described above. Those skilled in the art should understand that this application is not limited to the above embodiments. The embodiments and descriptions in the specification are merely the principles of this application. Various changes and modifications can be made to this application without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed application.

Claims

1. A two-stage cyclone functionalized membrane environmental sample enrichment and detection system, characterized in that, It includes a sample introduction unit, a two-stage cyclone separation unit, a membrane enrichment unit, a monitoring and execution unit, and a control unit; The sample introduction unit is used to introduce environmental samples into the system. The two-stage hydrocyclone separation unit includes a first-stage hydrocyclone (18) and a second-stage hydrocyclone (20) connected in series, which are used to discharge large and medium-sized particulate impurities in the sample through the underflow under centrifugal action and to transport the overflow containing the target analyte backward. The membrane enrichment unit includes a membrane module (21) with a built-in functional membrane for receiving the overflow from the secondary cyclone separator (20) and enriching the target material; The monitoring and execution unit is used to collect the injection flow rate, pre-membrane flow rate, pre-membrane pressure, and post-membrane pressure, and to perform pump and valve regulation; The control unit is used to control the process of environmental sample injection, two-stage hydrocyclone separation, membrane enrichment, and liquid discharge.

2. The two-stage cyclone functionalized membrane environmental sample enrichment and detection system as described in claim 1, characterized in that, The sample injection unit includes a sampling tube (2) with an anti-clogging head (3), a sampling tube interface (1), a quick connector (14), and a primary pump (7) connected in sequence. The outlet end of the primary pump (7) is connected to the primary hydrocyclone (18).

3. The two-stage cyclone functionalized membrane environmental sample enrichment and detection system as described in claim 2, characterized in that, The two-stage cyclone separation unit also includes a secondary pump (8), an overflow collection pipe (17) and a bottom flow drainage pipe (19). The overflow outlet of the primary cyclone separator (18) is connected to the secondary cyclone separator (20) via the overflow collection pipe (17), and the bottom flow outlets of both cyclones are connected to the bottom flow drainage pipe (19). The membrane enrichment unit also includes a three-stage pump (9), an inlet (22) and a drain pipe (4). The overflow outlet of the secondary hydrocyclone (20) is connected to the inlet (22) of the membrane module (21), and the liquid outlet of the membrane module (21) is connected to the drain pipe (4).

4. The two-stage cyclone functionalized membrane environmental sample enrichment and detection system as described in claim 3, characterized in that, The monitoring and execution unit includes a flow meter (10), a pressure gauge (11), a flow and pressure sensor (15), and a pneumatic valve (16). The control unit acquires the baseline initial flow rate and initial differential pressure after the system starts up, and calculates the average flow rate and flow fluctuation coefficient within a specified time window during operation.

5. The two-stage cyclone functionalized membrane environmental sample enrichment and detection system as described in claim 1, characterized in that, The control process of the control unit is as follows: Based on the underflow discharge ratio, flow fluctuation coefficient and differential pressure rise rate of the benchmark sampling section, the water sample type is determined according to the preset hierarchical discrimination rules and the corresponding control parameters are called from the parameter configuration table. Based on the collected flow rate and pressure, a target retention index and a membrane fouling risk index are constructed. The membrane fouling status is determined according to the priority order of local flow path anomaly, pore blockage, and surface accumulation. Based on this, the monitoring execution unit is adjusted in a coordinated manner to maintain the stable enrichment of the target. The target retention index is: The ratio of real-time in-membrane flow rate to injection flow rate, the complementary terms of flow rate fluctuation, and the complementary terms of underflow discharge flow rate to injection flow rate are given preset weights and then summed.

6. The two-stage cyclone functionalized membrane environmental sample enrichment and detection system as described in claim 5, characterized in that, The control unit calculates the pressure difference and its rate of rise between the membrane and the upstream and downstream pressures in real time. The process for obtaining the membrane fouling risk index is as follows: The real-time differential pressure growth ratio relative to the initial differential pressure, the differential pressure rise rate, and the membrane inlet flow rate decrease ratio relative to the initial membrane inlet flow rate are summed after being assigned preset weights.

7. The two-stage cyclone functionalized membrane environmental sample enrichment and detection system as described in claim 6, characterized in that, The determination process of the control unit is as follows: If the flow fluctuation coefficient exceeds the standard and the pressure difference jumps, it is determined to be a local flow path abnormality; If the flow path is normal, but the membrane fouling risk index exceeds the standard, the pressure difference continues to rise, and the flow rate before the membrane drops significantly, it is determined to be pore blockage. If the flow path is normal and not blocked, but the membrane fouling risk index exceeds the standard, the pressure difference continues to rise, and the flow rate in front of the membrane decreases slightly, it is judged as surface accumulation.

8. The two-stage cyclone functionalized membrane environmental sample enrichment and detection system as described in claim 5, characterized in that, The linkage adjustment process of the control unit is as follows: When the surface is deposited, keep the speed of the first-stage pump (7) and the second-stage pump (8) basically unchanged, reduce the speed of the third-stage pump (9) and drive the pneumatic valve (16) to perform short-cycle pulse unloading; When the channel is blocked, the speed of the secondary pump (8) and the tertiary pump (9) is reduced simultaneously, and the unloading opening of the pneumatic valve (16) is increased. When there is a local flow path abnormality, reduce the speed of the primary pump (7) to a low speed and adjust the opening and closing frequency of the pneumatic valve (16) to release the stagnant fluid.

9. The two-stage cyclone functionalized membrane environmental sample enrichment and detection system as described in claim 8, characterized in that, The hierarchical discrimination rule is as follows: When α ≥ 0.35 and γ ≥ γ h At that time, it was identified as a complex water sample with high sediment and high algae content; When α ≥ 0.35 and γ < γ h At that time, the water sample was identified as a high-sediment type. When α < 0.35 and β ≥ 0.20 and γ ≥ γ h At that time, it was identified as a high-algae colloidal water sample; If none of the above conditions are met, the sample is classified as a conventional water sample. Where α is the underflow discharge ratio, β is the flow fluctuation coefficient, and γ is the pressure difference rise rate. h For the high threshold of the rate of increase of differential pressure, γ h = 3 × γ0, where γ0 is the average differential pressure rise rate within the reference sampling segment.

10. The two-stage cyclone functionalized membrane environmental sample enrichment and detection system as described in claim 9, characterized in that, The control unit generates the target pump speeds for the primary pump (7), secondary pump (8), and tertiary pump (9), respectively: The target pump speed of the primary pump (7) is: N 1,k+1 = N 1,k +C 1,1 ×(I M,lim - I M,k )-C 1,2 ×(α k -α ref ); The target pump speed of the secondary pump (8) is: N 2,k+1 = N 2,k +C 2,1 ×(I T,ref - I T,k )+C 2,2 ×(α k -α ref ); The target pump speed of the three-stage pump (9) is: N 3,k+1 = N 3,k +C 3,1 ×(I T,ref - I T,k )-C 3,2 ×(I M,k - I M,lim ); Where, N 1,k N 2,k N 3,k These represent the target pump speeds for the primary, secondary, and tertiary pumps in the current control cycle, respectively, N. 1,k+1 N 2,k+1 N 3,k+1 These are the target pump speeds for the primary, secondary, and tertiary pumps in the next control cycle, respectively. T,k To retain the index for the target, I T,ref Reserve the exponential setpoint for the target, I M,k I is the membrane fouling risk index. M,lim α is the upper limit of membrane fouling risk. k α represents the underflow discharge ratio. ref Set the target underflow discharge ratio, C 1,1 C 1,2 C 2,1 C 2,2 C 3,1 C 3,2 This is the adjustment coefficient.

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