High-concentration sample automatic two-step dilution system based on intelligent feedback control and analysis method

Abstract

The invention relates to the field of sample dilution, in particular to a high-concentration sample automatic two-step dilution system and analysis method based on intelligent feedback control, and the system comprises a primary pre-dilution module, a secondary dynamic dilution module, a sensing module, an intelligent feedback control module and a dilution cavity parallel module; a two-step dilution structure is introduced, and an intelligent feedback control module is combined, so that dynamic and accurate dilution of a high-concentration sample is realized. The first-stage pre-dilution module and the second-stage dynamic dilution module are matched to finish the steps of primary dilution and precise dilution respectively, so that the dilution efficiency is improved. The particle concentration, size distribution and morphology characteristic data collected by the sensing module provide support for dynamic optimization of the dilution process. The intelligent feedback control module adjusts sample flow velocity and diluent flow velocity parameters in real time, the problems of particle coincidence and insufficient dilution are effectively avoided, alternate operation of the multiple dilution cavity parallel modules is seamlessly switched through control logic, and efficient operation of the whole system is ensured.

Description

Technical Field

[0001] The invention relates to the field of sample dilution, and in particular to an automatic two-step dilution system and an analysis method for high-concentration samples based on intelligent feedback control. Background Art

[0002] The analysis of particle size distribution (PSD) is of great significance in the fields of industrial production, material research and quality control. The physical properties of particles, such as size distribution, morphology and concentration, directly affect the performance of the final product and the stability of the intermediate process. In the prior art, single particle sensing (SPOS) methods, such as single particle optical sensing (SPOS) and electrical zone method, are widely used in particle size analysis. However, these methods have strict requirements on the particle concentration of the sample, and high-concentration samples need to be diluted to an appropriate level to obtain accurate PSD data. For this reason, the dilution system has become an indispensable part of the particle analysis process, especially for online real-time detection systems, and its dilution efficiency and accuracy are crucial to the entire detection process.

[0003] Existing dilution systems mostly use static non-adjustable dilution systems with fixed dilution multiples or simple flow rate adjustment, and use light resistance sensors to detect particle size. However, these systems generally have the following shortcomings:

[0004] The dilution systems in the prior art mostly use a fixed dilution factor, and the ratio of the dilution chamber volume and the diluent flow rate is set in advance through experience. However, this fixed mode has obvious limitations in practical applications. The sample concentration is uncertain, and the concentration of samples from different batches varies significantly due to production conditions or process adjustments. It is difficult to accurately adapt the fixed dilution factor to all samples, resulting in insufficient dilution of some samples, causing particle overlap and affecting the accuracy of PSD measurement. For samples with a concentration lower than the overlap limit but higher than the optimal detection concentration, excessive dilution leads to insufficient particle count and poor statistical significance, which increases the detection time and introduces statistical errors. In addition, impurities in the diluent further interfere with the results and cannot accurately reflect the true particle distribution of the sample.

[0005] Traditional particle detection systems mainly rely on light obstruction sensors, which calculate the equivalent diameter of particles by monitoring the particle's blocking signal of the laser. However, this method has inherent defects: the light obstruction method is only applicable to particle models equivalent to spheres, and cannot accurately identify the true size and morphology of complex or non-spherical particles. For samples with complex material properties, this method causes significant measurement errors. Due to the different materials of particles, their absorption and scattering characteristics of light are different, but the light obstruction method cannot distinguish these differences, resulting in a lack of comprehensiveness and reliability in particle detection results. In the detection process of high-concentration samples, the phenomenon of particle overlap will further aggravate signal distortion, greatly reducing the effectiveness of the light obstruction method.

[0006] In practical applications, the dilution system needs to be cleaned frequently to prevent sample residues from interfering with the next dilution. However, existing dilution systems are usually only equipped with one set of dilution chambers. When the dilution chamber enters the cleaning state, the entire detection process needs to be suspended, which significantly reduces the overall efficiency of the system. In addition, the time is long, especially for high-viscosity or difficult-to-remove sample residues, the cleaning process of the dilution chamber becomes a bottleneck of the entire detection process. The inability to dilute the sample during cleaning leads to the accumulation of test samples, which seriously affects the production rhythm of high-frequency detection scenarios. During the frequent switching and cleaning of the dilution chamber, there are switching delays and signal fluctuations, which further affect the stability of the dilution system and the reliability of the measurement results. Summary of the invention

[0007] The object of the present invention is to provide an automatic two-step dilution system and analysis method for high-concentration samples based on intelligent feedback control, so as to solve the technical problems raised in the above-mentioned background technology.

[0008] Based on the above ideas, the present invention provides the following technical solutions:

[0009] An automatic two-step dilution system for high-concentration samples based on intelligent feedback control comprises: a primary pre-dilution module, a secondary dynamic dilution module, a sensor module, an intelligent feedback control module and a dilution chamber parallel module; the primary pre-dilution module is provided with a sample injection unit and a diluent supply unit, and the primary dilution is completed through the pre-dilution chamber; the primary pre-dilution multiple is controlled by adjusting the volume of the sample injected into the primary dilution chamber; the diluted sample enters the secondary dynamic dilution module through a flow channel, and transmits a real-time concentration signal to the intelligent feedback control module at the same time; the secondary dynamic dilution module comprises a secondary dilution chamber for receiving the output of the primary dilution module The sample flow and diluent flow of the first dilution chamber and the diluent flow are adjusted by the diluent fixed flow rate unit and the sample flow control unit; the diluted sample is output to the sensing module; the sensing module includes a flow meter, a light resistance sensor and a CCD high-speed camera, which are used to collect particle concentration, particle size distribution and morphology data; the particle concentration output from the first dilution chamber and the second dilution chamber is detected in real time, and the concentration change data and the coincidence rate are transmitted to the intelligent feedback control module; the CCD camera is located in the flow channel after the second dynamic dilution module, which is used to supplement the particle morphology analysis information; the intelligent feedback control module receives the concentration signal of the sensing module , particle count rate and PSD data, and dynamically adjust the dilution parameters of the primary dilution module and the secondary dynamic dilution module through algorithms; calculate the dilution factor according to the dilution target concentration, and send a control signal to adjust the speed at which the sample flows out of the primary dilution chamber; monitor the dilution liquid flow rate in the secondary dilution module at the same time to ensure that the concentration is stable within the set target range, so as to form a dynamic and adjustable dilution system; the dilution chamber parallel module, through the dilution chamber switching mechanism, realizes that when one set of dilution chambers is used for cleaning, the other set of dilution chambers continue to work, ensuring the continuity of the dilution process; the dilution chamber status is monitored by the intelligent feedback control module, and automatically switches to the next set according to the priority. The dilution sample output by the first-stage pre-dilution module directly enters the second-stage dynamic dilution module through a pipeline, and the diluted concentration signal is fed back to the intelligent feedback control module in real time. The sensor module simultaneously monitors the particle concentration, flow rate and PSD data during the two-stage dilution process, providing the basis for the intelligent feedback control module to optimize the dilution parameters. The intelligent feedback control module adjusts the parameters of the first-stage and second-stage dynamic dilution modules in real time according to the sensor data to achieve dynamic optimization of the dilution factor. The alternating operation of multiple sets of dilution chamber parallel modules is seamlessly switched through the control logic, ensuring that the entire system operates efficiently while avoiding downtime caused by dilution chamber cleaning.

[0010] The present invention realizes dynamic and precise dilution of high-concentration samples by introducing a two-step dynamic dilution structure and combining it with an intelligent feedback control module. The first-level pre-dilution module cooperates with the second-level dynamic dilution module to complete the preliminary dilution and precise dilution steps respectively, which not only improves the dilution efficiency, but also solves the problem that it is difficult to take into account the concentration stability and flexible adjustment of the dilution factor during a single dilution process. The modules work together through real-time signal transmission, and the particle concentration, size distribution and morphological feature data collected by the sensor module provide strong support for the dynamic optimization of the dilution process. The intelligent feedback control module adjusts the sample flow rate and dilution liquid flow rate parameters in real time to effectively avoid the problems of particle overlap and insufficient dilution. Multiple sets of dilution chamber parallel working modules further improve the work efficiency of the system and ensure that the continuity of the dilution process can be maintained during the cleaning process. The system can be widely used in industrial production environments that require high-precision particle size analysis, significantly improves test accuracy and operating efficiency, and at the same time makes up for the shortcomings of the prior art that dilution concentration and efficiency are difficult to optimize.

[0011] Preferably, a dilution factor optimization algorithm is included to dynamically adjust the dilution multiple of the primary pre-dilution module and the dilution liquid flow rate of the secondary dynamic dilution module, specifically including the following steps:

[0012] S1. Initialize the system, preset the volume of the first dilution chamber, the flow rate of the second dilution liquid and the coincidence limit of the sensor;

[0013] S2, collecting the sample injection flow rate of the first-level pre-dilution module, and calculating the current pre-dilution factor in combination with the dilution chamber volume;

[0014] S3, using the sensor module to detect the particle concentration after the primary dilution in real time, and determine whether it meets the input concentration requirement of the secondary dynamic dilution module; if not, adjust the sample injection flow rate and update the primary dilution multiple;

[0015] S4. According to the output concentration of the secondary dynamic dilution module and the sensor signal feedback, the secondary dilution liquid flow rate is further optimized and the final dilution factor is dynamically corrected.

[0016] Through precise dilution factor optimization strategies, the working parameters of the primary pre-dilution module and the secondary dynamic dilution module are dynamically adjusted to ensure that the final dilution factor can adapt to the constraints of sample concentration changes and sensor overlap rate. The dynamic adjustment of the dilution multiple achieves efficient control of particle concentration within the target range, avoiding the problem of insufficient particle number or significantly prolonged measurement time due to excessive dilution factors, while overcoming the impact of diluent contamination caused by excessive dilution. Through the real-time acquisition of concentration signals, the algorithm can make mid-course corrections during the dilution process, allowing the dilution factor optimization process to quickly converge to the optimal value, thereby significantly improving measurement efficiency and dilution accuracy. The introduction of this algorithm upgrades the dilution system from the traditional fixed-multiple dilution to an adaptive dynamic adjustment mode, providing a more stable and flexible basic guarantee for particle size analysis.

[0017] Preferably, the primary pre-dilution multiple formula includes:

[0018]

[0019] Among them, DF1 is the first-stage dilution multiple, V1 is the first-stage dilution chamber volume, F S is the sample injection flow rate, t is the unit time;

[0020] The secondary pre-dilution multiple formula includes:

[0021]

[0022] Among them, DF2 is the secondary dilution factor, F D is the diluent flow rate

[0023] The final dilution factor calculation formula includes:

[0024] DF=DF1×DF2

[0026] The specific formula used in the dilution factor optimization algorithm provides a clear calculation basis for dynamically adjusting the dilution multiple and flow rate, ensuring that the algorithm can achieve real-time optimization of the dilution factor in an efficient and accurate manner. The primary dilution multiple formula directly calculates the pre-dilution multiple based on the dilution chamber volume and the sample injection volume, providing a stable basic condition for subsequent dilution steps. The secondary dilution multiple formula determines the final dilution effect by fixing the ratio of the diluent flow rate to the sample flow rate, so that the output concentration can meet the measurement requirements of the sensor. The final dilution factor formula combines the calculation results of the primary and secondary dilution multiples, providing clear theoretical support for the adjustment of the dynamic dilution factor. Through these formulas, the accuracy and controllability of the entire dilution process have been greatly enhanced, avoiding the measurement deviation problem caused by unreasonable dilution factor setting in the traditional dilution process.

[0027] Preferably, a particle concentration dynamic detection algorithm is included, and a CCD high-speed camera and a light resistance sensor are used to jointly analyze the sample particle characteristics, specifically including the following steps:

[0028] S1. Install a CCD probe in the flow channel at the rear end of the secondary dynamic dilution module to collect particle images;

[0029] S2. Analyze the morphology and material properties of the particles based on the image information obtained by the CCD probe;

[0030] S3, determining the equivalent spherical diameter of the particles in combination with the particle size information output by the light resistance sensor;

[0031] S4, comparing the particle concentration with the sensor coincidence limit, if it exceeds the limit, sending an adjustment signal to the feedback control module;

[0032] S5. Dynamically adjust the primary dilution multiple or the secondary dilution flow rate to ensure that the particle concentration is within the target range.

[0033] By introducing the combined use of CCD high-speed cameras and light-resistance sensors, the shortcomings of the traditional light-resistance method in particle morphology and material recognition are made up, providing more comprehensive and accurate data support for particle size distribution analysis. The CCD high-speed camera can collect particle image information in real time and accurately analyze the particle shape characteristics. Combined with the particle size detection results of the light-resistance sensor, it can better evaluate the equivalent spherical diameter and actual morphological characteristics of the particles. This multi-dimensional particle detection method significantly improves the accuracy of PSD measurement and effectively avoids measurement distortion caused by the complexity of particle shape. In addition, the algorithm can provide more reliable parameter support for the feedback control module through dynamic monitoring of particle concentration and morphological characteristics, realize further optimization of the dilution factor, and lay a solid foundation for the intelligent operation of the entire dilution system.

[0034] Preferably, the calculation formula of the equivalent sphere includes:

[0035]

[0036] Among them, d eq is the equivalent spherical diameter of the particle, V p is the particle volume;

[0037] The particle concentration calculation formula includes:

[0038]

[0039] Where C is the particle concentration, N is the total number of particles, V t is the total volume of the sample;

[0040] The dynamic adjustment signal calculation formula includes:

[0041] ΔDF=k×(CC target )

[0042] Where ΔDF is the adjustment amount of the dilution factor, k is the adjustment coefficient, and C target is the target particle concentration.

[0043] The formula provides a specific calculation method for morphology and concentration analysis, and provides a scientific basis for the accurate measurement of particle equivalent spherical diameter and sample concentration. The equivalent spherical diameter formula calculates the effective size of the particle through the particle volume, so that complex particle shape data can be converted into standardized parameters, thereby improving the versatility and accuracy of particle size analysis. The concentration calculation formula combines the total number of particles and the total volume of the sample, providing a direct quantitative indicator for real-time monitoring of particle concentration during the dilution process. The dynamic adjustment signal formula calculates the adjustment amount of the dilution factor through the difference between the particle concentration and the target concentration, realizing closed-loop control of the dilution process. Through these formulas, the system can not only accurately evaluate the particle size and concentration, but also dynamically adjust the dilution parameters, thereby significantly improving the efficiency and accuracy of the dilution system, and solving the problem of incomplete particle concentration and morphology detection in the prior art.

[0044] Preferably, the dilution chamber parallel module includes a multi-dilution chamber parallel control algorithm for realizing the alternating use of the primary dilution chamber, specifically including the following steps:

[0045] S1. Initialize two sets of primary dilution chambers, marked as "working chamber" and "standby chamber";

[0046] S2. When the "working chamber" enters the cleaning state, the sample is automatically switched to be injected into the "standby chamber";

[0047] S3. Record the usage status of each dilution chamber and automatically assign cleaning priority according to the frequency of use;

[0048] S4. Use the feedback control module to coordinate the dilution chamber switching process to ensure dilution continuity.

[0049] The multi-dilution chamber parallel control algorithm solves the limitation of the traditional dilution system that it cannot work continuously when the dilution chamber is cleaned by adding a spare dilution chamber design. The alternating dilution chamber design enables the system to use the spare dilution chamber to maintain the continuity of the dilution process when one dilution chamber is used for cleaning, thereby significantly improving the test efficiency and system stability. The algorithm automatically assigns cleaning priorities based on the frequency of use and cleaning requirements of the dilution chamber to ensure the rationality and efficiency of dilution chamber switching. The participation of the intelligent feedback control module makes the dilution chamber switching process more accurate and seamless, avoiding concentration fluctuations or dilution delays that may be caused during the switching process. Through the flexible alternating use of multiple dilution chambers, the system significantly improves the dilution efficiency, adapts to the needs of high-frequency testing scenarios, and provides reliable technical support for industrial applications.

[0050] Preferably,

[0051] The calculation formula for the dilution chamber switching time includes:

[0052]

[0053] Among them, T switch is the time required for dilution chamber switching, V f is the volume of cleaning fluid, F f is the cleaning fluid flow rate;

[0054] The status priority calculation formulas include:

[0055]

[0056] Among them, P i is the dilution chamber priority, T i is the dilution chamber usage time, T t is the total running time.

[0057] The formulas in the multi-dilution chamber parallel control algorithm provide specific calculation methods for switching delays and priority allocation, providing theoretical support for the efficient switching of dilution chambers. The dilution chamber switching delay formula calculates the time required for cleaning through the ratio of the cleaning liquid volume and flow rate, providing a basis for the optimization of the dilution chamber switching plan. The usage status priority formula calculates the priority based on the ratio of the dilution chamber usage time to the total operating time, ensuring that frequently used dilution chambers can be cleaned first, effectively improving the efficiency of dilution chamber management. Through these formulas, the dilution system can achieve precise control when switching the dilution chamber, avoiding the interruption of the dilution process or the decrease in efficiency due to improper switching. Ultimately, the automation and intelligence of dilution chamber management is realized, providing a key guarantee for the continuous and stable operation of the dilution system.

[0058] An automatic two-step dilution analysis method for high-concentration samples based on intelligent feedback control comprises using the automatic two-step dilution system for high-concentration samples based on intelligent feedback control.

[0059] Compared with the prior art, the present invention has the following beneficial effects:

[0060] By dynamically optimizing the dilution factor, the problems of inaccurate concentration control and inflexible dilution multiple adjustment in the dilution of high-concentration samples are solved. The first-level pre-dilution module calculates the dilution multiple based on the sample injection flow rate and the dilution chamber volume, providing a stable basis for subsequent dilution. The second-level dynamic dilution module combines a fixed flow rate diluent with a real-time adjusted sample flow rate to accurately control the final dilution multiple, so that the output sample concentration is stable within the target range. The algorithm supports dynamic adjustment of the sensor coincidence limit, effectively avoiding measurement distortion caused by particle coincidence, while ensuring that the concentration of high-concentration samples after dilution is adapted to a variety of detection requirements. Through real-time data acquisition and feedback mechanisms, the algorithm can quickly converge to the optimal dilution factor, significantly improving the efficiency and accuracy of the dilution process, while reducing measurement errors and resource waste caused by improper dilution.

[0061] Combining a CCD high-speed camera with a light-resistance sensor, by jointly analyzing particle concentration, morphology and size distribution, the inadequacy of morphology and material recognition capabilities in existing particle detection technologies is made up. The particle size data provided by the light-resistance sensor is combined with the morphological features captured by the CCD camera, making the calculation of the equivalent sphere diameter more accurate while improving the accuracy of PSD measurements. The algorithm dynamically monitors changes in particle concentration and particle size, and can identify and feedback abnormal concentration conditions and adjust dilution parameters in a timely manner to avoid measurement distortion caused by particle overlap or uneven particle distribution. In addition, the introduction of this algorithm enables the system to not only detect the basic characteristics of particles, but also perform multi-dimensional analysis of complex particle morphologies, adapt to more complex analysis scenarios, and greatly expand the scope of application and detection capabilities of the dilution system.

[0062] By designing a parallel working mechanism for multiple dilution chambers, the efficiency and stability of the dilution system are significantly improved. The alternating operation mode of the dilution chambers allows one dilution chamber to continue diluting while the other chamber is performing a cleaning task, thereby achieving seamless and continuous operation of the system and overcoming the pause problem of the traditional dilution system during cleaning. Through the dynamic allocation of dilution chamber usage priorities, the algorithm optimizes the cleaning frequency and resource utilization efficiency, avoiding the problem of unstable dilution caused by excessive use or insufficient cleaning of the dilution chamber. In addition, the precise control of the switching delay ensures that the concentration fluctuation is minimized during the dilution chamber switching process and maintains the consistency of the dilution output. The algorithm significantly improves the adaptability of the dilution system in high-frequency and diversified sample testing scenarios, while reducing the need for manual intervention, providing strong technical support for large-scale industrial applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] Figure 1 The present invention is a schematic diagram of the module relationship of an automatic two-step dilution system for high-concentration samples based on intelligent feedback control and an analysis method.

[0064] Figure 2 The present invention is a schematic diagram of a pipeline of an automatic two-step dilution system and an analysis method for high-concentration samples based on intelligent feedback control.

[0065] In the figure, 1. First-level pre-dilution module; 2. Second-level dynamic dilution module; 3. Sample injection unit; 4. Dilution liquid supply unit; 5. Sensor module; 6. Dilution chamber parallel module; 7. Intelligent feedback control module. DETAILED DESCRIPTION

[0066] An automatic two-step dilution system for high-concentration samples based on intelligent feedback control comprises: a primary pre-dilution module, a secondary dynamic dilution module, a sensor module, an intelligent feedback control module and a dilution chamber parallel module; the primary pre-dilution module is provided with a sample injection unit and a diluent supply unit, and the primary dilution is completed through the pre-dilution chamber; the primary pre-dilution multiple is controlled by adjusting the volume of the sample injected into the primary dilution chamber; the diluted sample enters the secondary dynamic dilution module through a flow channel, and transmits a real-time concentration signal to the intelligent feedback control module at the same time; the secondary dynamic dilution module comprises a secondary dilution chamber for receiving the output of the primary dilution module The sample flow and diluent flow of the first dilution chamber and the diluent flow are adjusted by the diluent fixed flow rate unit and the sample flow control unit; the diluted sample is output to the sensing module; the sensing module includes a flow meter, a light resistance sensor and a CCD high-speed camera, which are used to collect particle concentration, particle size distribution and morphology data; the particle concentration output from the first dilution chamber and the second dilution chamber is detected in real time, and the concentration change data and the coincidence rate are transmitted to the intelligent feedback control module; the CCD camera is located in the flow channel after the second dynamic dilution module, which is used to supplement the particle morphology analysis information; the intelligent feedback control module receives the concentration signal of the sensing module , particle count rate and PSD data, and dynamically adjust the dilution parameters of the primary dilution module and the secondary dynamic dilution module through algorithms; calculate the dilution factor according to the dilution target concentration, and send a control signal to adjust the speed at which the sample flows out of the primary dilution chamber; monitor the dilution liquid flow rate in the secondary dilution module at the same time to ensure that the concentration is stable within the set target range, so as to form a dynamic and adjustable dilution system; the dilution chamber parallel module, through the dilution chamber switching mechanism, realizes that when one set of dilution chambers is used for cleaning, the other set of dilution chambers continue to work, ensuring the continuity of the dilution process; the dilution chamber status is monitored by the intelligent feedback control module, and automatically switches to the next set according to the priority. The dilution sample output by the first-stage pre-dilution module directly enters the second-stage dynamic dilution module through a pipeline, and the diluted concentration signal is fed back to the intelligent feedback control module in real time. The sensor module simultaneously monitors the particle concentration, flow rate and PSD data during the two-stage dilution process, providing the basis for the intelligent feedback control module to optimize the dilution parameters. The intelligent feedback control module adjusts the parameters of the first-stage and second-stage dynamic dilution modules in real time according to the sensor data to achieve dynamic optimization of the dilution factor. The alternating operation of multiple sets of dilution chamber parallel modules is seamlessly switched through the control logic, ensuring that the entire system operates efficiently while avoiding downtime caused by dilution chamber cleaning.

[0067] The present invention realizes dynamic and precise dilution of high-concentration samples by introducing a two-step dilution structure and combining it with an intelligent feedback control module. The first-level pre-dilution module cooperates with the second-level dynamic dilution module to complete the preliminary dilution and precise dilution steps respectively, which not only improves the dilution efficiency, but also solves the problem that it is difficult to take into account the concentration stability and flexible adjustment of the dilution factor during a single dilution process. The modules work together through real-time signal transmission, and the particle concentration, size distribution and morphological feature data collected by the sensor module provide strong support for the dynamic optimization of the dilution process. The intelligent feedback control module adjusts the sample flow rate and dilution liquid flow rate parameters in real time to effectively avoid the problems of particle overlap and insufficient dilution. Multiple sets of dilution chamber parallel working modules further improve the working efficiency of the system and ensure that the continuity of the dilution process can be maintained during the cleaning process. The system can be widely used in industrial production environments that require high-precision particle size analysis, significantly improves the test accuracy and operating efficiency, and at the same time makes up for the shortcomings of the prior art that the dilution concentration and efficiency are difficult to optimize.

[0068] Specifically, it includes a dilution factor optimization algorithm for dynamically adjusting the dilution multiple of the primary pre-dilution module and the dilution liquid flow rate of the secondary dynamic dilution module, and specifically includes the following steps:

[0069] S1. Initialize the system, preset the volume of the first dilution chamber, the flow rate of the second dilution liquid and the coincidence limit of the sensor;

[0070] S2, collecting the sample injection flow rate of the first-level pre-dilution module, and calculating the current pre-dilution factor in combination with the dilution chamber volume;

[0071] S3, using the sensor module to detect the particle concentration after the primary dilution in real time, and determine whether it meets the input concentration requirement of the secondary dynamic dilution module; if not, adjust the sample injection flow rate and update the primary dilution multiple;

[0072] S4. According to the output concentration of the secondary dynamic dilution module and the sensor signal feedback, the secondary dilution liquid flow rate is further optimized and the final dilution factor is dynamically corrected.

[0073] Through precise dilution factor optimization strategies, the working parameters of the primary pre-dilution module and the secondary dynamic dilution module are dynamically adjusted to ensure that the final dilution factor can adapt to the constraints of sample concentration changes and sensor overlap rate. The dynamic adjustment of the dilution multiple achieves efficient control of particle concentration within the target range, avoiding the problem of insufficient particle number or significantly prolonged measurement time due to excessive dilution factors, while overcoming the impact of diluent contamination caused by excessive dilution. Through the real-time acquisition of concentration signals, the algorithm can make mid-course corrections during the dilution process, allowing the dilution factor optimization process to quickly converge to the optimal value, thereby significantly improving measurement efficiency and dilution accuracy. The introduction of this algorithm upgrades the dilution system from the traditional fixed-multiple dilution to an adaptive dynamic adjustment mode, providing a more stable and flexible basic guarantee for particle size analysis.

[0074] Specifically, the primary pre-dilution multiple formula includes:

[0075]

[0076] Among them, DF1 is the first-stage dilution multiple, V1 is the first-stage dilution chamber volume, F S is the sample injection flow rate, t is the unit time;

[0077] The secondary pre-dilution multiple formula includes:

[0078]

[0079] Among them, DF2 is the secondary dilution factor, F D is the diluent flow rate

[0080] The final dilution factor calculation formula includes:

[0081] DF=DF1×DF2

[0083] The specific formula used in the dilution factor optimization algorithm provides a clear calculation basis for dynamically adjusting the dilution multiple and flow rate, ensuring that the algorithm can achieve real-time optimization of the dilution factor in an efficient and accurate manner. The primary dilution multiple formula directly calculates the pre-dilution multiple based on the dilution chamber volume and the sample injection flow rate, providing a stable basic condition for subsequent dilution steps. The secondary dilution multiple formula determines the final dilution effect by fixing the ratio of the diluent flow rate to the sample flow rate, so that the output concentration can meet the measurement requirements of the sensor. The final dilution factor formula combines the calculation results of the primary and secondary dilution multiples, providing clear theoretical support for the adjustment of the dynamic dilution factor. Through these formulas, the accuracy and controllability of the entire dilution process have been greatly enhanced, avoiding the measurement deviation problem caused by unreasonable dilution factor setting in the traditional dilution process.

[0084] When used, the sample is injected into the dilution chamber at a certain flow rate through the injection unit of the primary dilution module, and the diluent enters the dilution chamber at a specific flow rate through the dilution supply unit and mixes with the sample to complete the initial dilution. The volume of the dilution chamber is fixed by design, providing a basis for the primary dilution multiple. A flow meter and a dilution chamber volume sensor are used to monitor the flow rate and chamber volume in real time.

[0085] Use the formula to calculate the first-order dilution factor.

[0086] V1 is the fixed dilution chamber volume, which provides physical constraints.

[0087] F S The sample injection flow rate is dynamically adjusted to optimize the dilution factor.

[0088] T is the flow rate per unit time, ensuring the calculation accuracy.

[0089] The sample injection flow rate FSF_SFS is dynamically adjusted through the feedback module to maintain a reasonable first-level dilution factor.

[0090] In the secondary dynamic dilution module, the diluent is injected at a fixed flow rate of 60-120 ml / min, and the sample flow rate F of the primary dilution output S Mix with it to complete the secondary dilution. The secondary dilution factor is calculated using the formula. The final dilution factor is used to dynamically adjust the sample flow rate of the primary module to ensure that the output sample concentration meets the coincidence limit of the sensor.

[0091] The primary formula calculates the dilution factor by the flow rate ratio and volume relationship in the dilution chamber, and the secondary formula uses the flow rate ratio of the diluent and the sample to provide precise concentration control. The final factor optimizes the dilution effect to ensure the concentration adaptability of the sample during detection.

[0092] Specifically, it includes a particle concentration dynamic detection algorithm, using a CCD high-speed camera and a light resistance sensor to jointly analyze the sample particle characteristics, and specifically includes the following steps:

[0093] S1. Install a CCD probe in the flow channel at the rear end of the secondary dynamic dilution module to collect particle images;

[0094] S2. Analyze the morphology and material properties of the particles based on the image information obtained by the CCD probe;

[0095] S3, determining the equivalent spherical diameter of the particles in combination with the particle size information output by the light resistance sensor;

[0096] S4, comparing the particle concentration with the sensor coincidence limit, if it exceeds the limit, sending an adjustment signal to the feedback control module;

[0097] S5. Dynamically adjust the primary dilution multiple or the secondary dilution flow rate to ensure that the particle concentration is within the target range.

[0098] By introducing the combined use of CCD high-speed cameras and light-resistance sensors, the shortcomings of the traditional light-resistance method in particle morphology and material recognition are made up, providing more comprehensive and accurate data support for particle size distribution analysis. The CCD high-speed camera can collect particle image information in real time and accurately analyze the particle shape characteristics. Combined with the particle size detection results of the light-resistance sensor, it can better evaluate the equivalent spherical diameter and actual morphological characteristics of the particles. This multi-dimensional particle detection method significantly improves the accuracy of PSD measurement and effectively avoids measurement distortion caused by the complexity of particle shape. In addition, the algorithm can provide more reliable parameter support for the feedback control module through dynamic monitoring of particle concentration and morphological characteristics, realize further optimization of the dilution factor, and lay a solid foundation for the intelligent operation of the entire dilution system.

[0099] Specifically, the calculation formula of the equivalent sphere includes:

[0100]

[0101] Among them, d eq is the equivalent spherical diameter of the particle, V p is the particle volume;

[0102] The particle concentration calculation formula includes:

[0103]

[0104] Where C is the particle concentration, N is the total number of particles, V t is the total volume of the sample;

[0105] The dynamic adjustment signal calculation formula includes:

[0106] ΔDF=k×(CC target )

[0107] Where ΔDF is the adjustment amount of the dilution factor, k is the adjustment coefficient, and C target is the target particle concentration.

[0108] The formula provides a specific calculation method for morphology and concentration analysis, and provides a scientific basis for the accurate measurement of particle equivalent spherical diameter and sample concentration. The equivalent spherical diameter formula calculates the effective size of the particle through the particle volume, so that complex particle shape data can be converted into standardized parameters, thereby improving the versatility and accuracy of particle size analysis. The concentration calculation formula combines the total number of particles and the total volume of the sample, providing a direct quantitative indicator for real-time monitoring of particle concentration during the dilution process. The dynamic adjustment signal formula calculates the adjustment amount of the dilution factor through the difference between the particle concentration and the target concentration, realizing closed-loop control of the dilution process. Through these formulas, the system can not only accurately evaluate the particle size and concentration, but also dynamically adjust the dilution parameters, thereby significantly improving the efficiency and accuracy of the dilution system, and solving the problem of incomplete particle concentration and morphology detection in the prior art.

[0109] When used specifically,

[0110] The light-blocking sensor is used to monitor the light-blocking signal of particles passing through the sensing area in real time to obtain the equivalent diameter of the particles. The light source of the sensor emits a laser to monitor the changes in light intensity, and the equivalent spherical diameter of the particles is calculated using a formula.

[0111] The CCD high-speed camera captures real-time images of particles passing through the flow channel, extracts particle morphology information, and supplements the shape defects of the light-blocking method. The camera transmits the image to the processing unit, identifies the shape characteristics of the particles (such as round, elliptical, etc.), and matches them with the particle equivalent diameter data calculated by the light-blocking method.

[0112] The particle concentration is calculated using the formula, where N is the number of particles counted by the light-blocking sensor and the CCD camera. t The sample volume sensor records the outflow data of the dilution chamber. The concentration data is fed back to the intelligent control module. If it exceeds the sensor overlap limit, the control module will send a signal to adjust the dilution factor.

[0113] The light blocking method combined with the CCD camera detection method combines particle morphology with concentration data, making up for the shortcomings of a single detection technology and significantly improving the comprehensiveness and accuracy of particle detection.

[0114] Specifically, the dilution chamber parallel module includes a multi-dilution chamber parallel control algorithm for realizing the alternating use of the primary dilution chamber, which specifically includes the following steps:

[0115] S1. Initialize two sets of primary dilution chambers, marked as "working chamber" and "standby chamber";

[0116] S2. When the "working chamber" enters the cleaning state, the sample is automatically switched to be injected into the "standby chamber";

[0117] S3. Record the usage status of each dilution chamber and automatically assign cleaning priority according to the frequency of use;

[0118] S4. Use the feedback control module to coordinate the dilution chamber switching process to ensure dilution continuity.

[0119] The multi-dilution chamber parallel control algorithm solves the limitation of the traditional dilution system that it cannot work continuously when the dilution chamber is cleaned by adding a spare dilution chamber design. The alternating dilution chamber design enables the system to use the spare dilution chamber to maintain the continuity of the dilution process when one dilution chamber is used for cleaning, thereby significantly improving the test efficiency and system stability. The algorithm automatically assigns cleaning priorities based on the frequency of use and cleaning requirements of the dilution chamber to ensure the rationality and efficiency of dilution chamber switching. The participation of the intelligent feedback control module makes the dilution chamber switching process more accurate and seamless, avoiding concentration fluctuations or dilution delays that may be caused during the switching process. Through the flexible alternating use of multiple dilution chambers, the system significantly improves the dilution efficiency, adapts to the needs of high-frequency testing scenarios, and provides reliable technical support for industrial applications.

[0120] Specifically,

[0121] The calculation formula for the dilution chamber switching time includes:

[0122]

[0123] Among them, T switch is the time required for dilution chamber switching, V f is the volume of cleaning fluid, F f is the cleaning fluid flow rate;

[0124] The status priority calculation formulas include:

[0125]

[0126] Among them, P i is the dilution chamber priority, T i is the dilution chamber usage time, T t is the total running time.

[0127] The formulas in the multi-dilution chamber parallel control algorithm provide specific calculation methods for switching delay and priority allocation, providing theoretical support for the efficient switching of dilution chambers. The dilution chamber switching delay formula calculates the time required for cleaning through the ratio of the cleaning liquid volume and flow rate, providing a basis for the optimization of the dilution chamber switching plan. The usage status priority formula calculates the priority based on the ratio of the dilution chamber usage time to the total operating time, ensuring that frequently used dilution chambers can be cleaned first, effectively improving the efficiency of dilution chamber management. Through these formulas, the dilution system can achieve precise control when switching the dilution chamber, avoiding the interruption of the dilution process or the decrease in efficiency due to improper switching. Finally, the automation and intelligence of dilution chamber management are realized, providing a key guarantee for the continuous and stable operation of the dilution system.

[0128] Two sets of dilution chambers are configured, marked as "working chamber" and "standby chamber". The working chamber is used for diluting the current sample, and the standby chamber is cleaned and on standby. The sample injection is guided to the available dilution chamber through the flow channel switching valve. The flow meter monitors the sample flow to ensure stable concentration during the switching process. Record the usage time T of each dilution chamber i And cleaning time T f , use the formula to calculate the priority of each cavity, and give priority to cleaning the dilution cavity that is used frequently.

[0129] Ti is the cumulative usage time of the current dilution chamber, reflecting the frequency of use.

[0130] The priority data is used in the dilution chamber automatic switching logic to optimize the alternating operation efficiency of the dilution chambers.

[0131] Combined with the switching delay formula, the cleaning time of the dilution chamber is calculated to ensure that the system dilution process is not interrupted during the switching process. The cleaning time and priority directly guide the operation of the switching control valve to ensure the continuity and stability of the sample dilution.

[0132] The priority formula and switching delay formula provide quantitative indicators for dilution chamber management. The cleaning and switching logic achieves optimal decision-making through data-driven, avoiding the uncertainty caused by manual intervention, while ensuring the efficiency and stability of system operation.

[0133] An automatic two-step dilution analysis method for high-concentration samples based on intelligent feedback control comprises using the automatic two-step dilution system for high-concentration samples based on intelligent feedback control.

Claims

1. An automatic two-step dilution system for high-concentration samples based on intelligent feedback control, characterized in that: include: A primary pre-dilution module, a secondary dynamic dilution module, a sensor module, an intelligent feedback control module and a dilution chamber parallel module; The primary pre-dilution module is provided with a sample injection unit and a diluent supply unit, and the primary dilution is completed through the pre-dilution chamber; the primary pre-dilution multiple is controlled by adjusting the volume of the sample injected into the primary dilution chamber; the diluted sample enters the secondary dynamic dilution module through the flow channel, and transmits a real-time concentration signal to the intelligent feedback control module at the same time; The secondary dynamic dilution module includes a secondary dilution chamber, which is used to receive the sample flow and diluent flow output by the primary dilution module; adjust the final dilution factor through the diluent fixed flow rate unit and the sample flow control unit; and output the diluted sample to the sensor module; The sensing module includes a flow meter, a light resistance sensor and a CCD high-speed camera, which are used to collect particle concentration, particle size distribution and morphology data; real-time detection of the particle concentration output from the primary dilution chamber and the secondary dilution chamber, and transmission of concentration change data and coincidence rate to the intelligent feedback control module; the CCD camera is located in the flow channel after the secondary dynamic dilution module, and is used to supplement the particle morphology analysis information; The intelligent feedback control module receives the concentration signal, particle count rate and PSD data of the sensor module, dynamically adjusts the dilution parameters of the primary dilution module and the secondary dynamic dilution module through an algorithm; calculates the dilution factor according to the dilution target concentration, and sends a control signal to adjust the speed at which the sample flows out of the primary dilution chamber; and monitors the flow rate of the diluent in the secondary dilution module at the same time to ensure that the concentration is stable within the set target range, so as to form a dynamic and adjustable dilution system; The dilution chamber parallel module uses the dilution chamber switching mechanism to ensure that one set of dilution chambers is used for cleaning while the other set of dilution chambers continue to work, ensuring the continuity of the dilution process; the dilution chamber status is monitored by the intelligent feedback control module and automatically switched according to priority; The diluted sample output by the primary pre-dilution module directly enters the secondary dynamic dilution module through a pipeline, and the diluted concentration signal is fed back to the intelligent feedback control module in real time; The sensor module simultaneously monitors the particle concentration, flow rate and PSD data during the two-stage dilution process, providing the basis for the intelligent feedback control module to optimize the dilution parameters; The intelligent feedback control module adjusts the parameters of the primary and secondary dynamic dilution modules in real time according to the sensor data to achieve dynamic optimization of the dilution factor; The alternating operation of multiple sets of dilution chamber parallel modules is seamlessly switched through control logic, ensuring the efficient operation of the entire system while avoiding the waste of sample detection time due to dilution chamber cleaning, which can greatly improve sample detection efficiency.

2. According to claim 1, a high-concentration sample automatic two-step dilution system based on intelligent feedback control is characterized in that: The method includes a dilution factor optimization algorithm for dynamically adjusting the dilution multiple of the primary pre-dilution module and the dilution fluid flow rate of the secondary dynamic dilution module, and specifically includes the following steps: S1. Initialize the system, preset the volume of the first dilution chamber, the flow rate of the second dilution liquid and the coincidence limit of the sensor; S2, collecting the sample injection flow rate of the first-level pre-dilution module, and calculating the current pre-dilution factor in combination with the dilution chamber volume; S3, using the sensor module to detect the particle concentration after the primary dilution in real time, and determine whether it meets the input concentration requirement of the secondary dynamic dilution module; if not, adjust the sample injection flow rate and update the primary dilution multiple; S4. According to the output concentration of the secondary dynamic dilution module and the sensor signal feedback, the secondary dilution liquid flow rate is further optimized and the final dilution factor is dynamically corrected.

3. The automatic two-step dilution system for high-concentration samples based on intelligent feedback control according to claim 2, characterized in that: The primary pre-dilution multiple formula includes: Among them, DF1 is the first-stage dilution multiple, V1 is the first-stage dilution chamber volume, F S is the sample injection flow rate, t is the unit time; The secondary pre-dilution multiple formula includes: Among them, DF2 is the secondary dilution factor, F D is the diluent flow rate; The final dilution factor calculation formula includes: DF=DF1×DF2 4. The automatic two-step dilution system for high-concentration samples based on intelligent feedback control according to claim 3, characterized in that: Including a particle concentration dynamic detection algorithm, using a CCD high-speed camera and a light resistance sensor to jointly analyze the sample particle characteristics, specifically including the following steps: S1. Install a CCD probe in the flow channel at the rear end of the secondary dynamic dilution module to collect particle images; S2. Analyze the morphology and material properties of the particles based on the image information obtained by the CCD probe; S3, determining the equivalent spherical diameter of the particles in combination with the particle size information output by the light resistance sensor; S4, comparing the particle concentration with the sensor coincidence limit, if it exceeds the limit, sending an adjustment signal to the feedback control module; S5. Dynamically adjust the primary dilution multiple or the secondary dilution flow rate to ensure that the particle concentration is within the target range.

5. The automatic two-step dilution system for high-concentration samples based on intelligent feedback control according to claim 4, characterized in that: The calculation formula of the equivalent sphere includes: Among them, d eq is the equivalent spherical diameter of the particle, V p is the particle volume; The particle concentration calculation formula includes: Where C is the particle concentration, N is the total number of particles, V t is the total volume of the sample; The dynamic adjustment signal calculation formula includes: ΔDF=k×(C-C target ) Where ΔDF is the adjustment amount of the dilution factor, k is the adjustment coefficient, and C target is the target particle concentration.

6. The automatic two-step dilution system for high-concentration samples based on intelligent feedback control according to claim 5, characterized in that: The dilution chamber parallel module includes a multi-dilution chamber parallel control algorithm, which is used to realize the alternating use of the primary dilution chamber, and specifically includes the following steps: S1. Initialize two sets of primary dilution chambers, marked as "working chamber" and "standby chamber"; S2. When the "working chamber" enters the cleaning state, the sample is automatically switched to be injected into the "standby chamber"; S3. Record the usage status of each dilution chamber and automatically assign cleaning priority according to the frequency of use; S4. Use the feedback control module to coordinate the dilution chamber switching process to ensure dilution continuity.

7. The automatic two-step dilution system for high-concentration samples based on intelligent feedback control according to claim 6, characterized in that: The calculation formula for the dilution chamber switching time includes: Among them, T switch is the time required for dilution chamber switching, V f is the volume of cleaning fluid, F f is the cleaning fluid flow rate; The status priority calculation formulas include: Among them, P i is the dilution chamber priority, T i is the dilution chamber usage time, T t is the total running time.

8. An automatic two-step dilution analysis method for high-concentration samples based on intelligent feedback control, characterized in that: The method comprises using the automatic two-step dilution system for high-concentration samples based on intelligent feedback control as described in any one of claims 1 to 7.

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