Full-automatic precision comparison preparation method and system for dialysis concentrated solution

Abstract

The invention provides a dialysis concentrated solution full-automatic precision comparison preparation method and system, and solves the problems of main and distribution network control target disjunction, insufficient resource collaboration and safety and economy contradiction under the access of high-proportion new energy. The method comprises the steps of collecting interaction power and distributed energy data of a main network and a distribution network in real time, and predicting wind and light output and flexible load requirements through a neural network and a Monte Carlo algorithm; constructing a dual-objective optimization model with main network fluctuation stabilization and distribution network cost reduction, and dynamically generating a flexible DC device power instruction and a time-of-use electricity price strategy by adopting an improved particle swarm optimization algorithm; scheduling is executed through linkage of millisecond-level power control and demand response, and wind-light fluctuation is adapted in combination with 15-minute-level closed-loop rolling optimization; and realizing rapid fault isolation and graded recovery based on a load priority coefficient. The system covers five-layer architecture of data perception, prediction analysis, optimization decision, execution control and security fault tolerance, and supports cross-level data penetration and multi-time scale coordination.

Description

Technical Field

[0001] The present invention relates to the field of centralized hemodialysis fluid supply equipment, and in particular to a fully automatic precision comparison preparation method and system for dialysis concentrate. Background Art

[0002] Hemodialysis, as a core alternative treatment for end-stage renal disease, relies heavily on the quality and stability of the dialysate. Dialysate is prepared by mixing concentrate and reverse osmosis water in a specific ratio (typically a 1:34 dilution ratio for Solution A and a 1:44 dilution ratio for Solution B). The electrolyte concentration of the concentrate must be controlled within a ±2.5% tolerance (YY 0598 standard). Currently, there are two primary modes of obtaining dialysis concentrate in clinical practice: direct bottled concentrate and on-site centralized supply. The former relies on industrially premixed concentrate, which, while ensuring consistent composition, carries drawbacks such as high transportation costs (over 30% of the sales price), significant storage space requirements (average daily consumption of 120 L / 10 patients), and a short shelf life after opening (Solution B ≤ 24 hours). The latter, prepared in-house by medical institutions using dispensing equipment and delivered to dialysis machines via a pipeline network, significantly reduces the cost per treatment (approximately 40%) and has a penetration rate exceeding 80% in developed countries such as Japan.

[0003] The core of a centralized liquid supply system lies in the precision and reliability of the liquid dispensing device. The traditional system consists of a liquid dispensing device, a liquid storage device, a liquid supply pipeline, and an electrical system. Its workflow includes: liquid inlet control (liquid level or weight sensing) → drug powder feeding → mechanical stirring → conductivity detection → storage liquid transportation. In recent years, automation technology has been gradually applied to the liquid dispensing process. For example, the automatic preparation device for dialysis concentrate disclosed in patent CN201920006393.5 realizes the automatic feeding of B powder through a clamping and conveying unit and a bag breaking and shaking unit. Combined with a dust and corrosion prevention unit to reduce the risk of microbial contamination, the liquid dispensing time is shortened from 1-2 hours in the traditional manual mode to within 40 minutes, effectively suppressing the attenuation of dialysate alkalinity caused by the decomposition of sodium bicarbonate. Despite this, the accuracy and flexibility of liquid dispensing remain the key bottlenecks restricting the clinical promotion of this technology.

[0004] Existing liquid dispensing devices generally rely on liquid level sensors or weighing sensors for liquid inlet control. Liquid level control uses a pressure differential to measure water level, but fluctuations in inlet pressure (a ±0.1 MPa change can result in a liquid level error of up to 3 cm) and the impact of water flow from the top-inlet method can cause measurement distortion, with actual inlet volume deviations as high as ±5%. While weighing control partially addresses the fluctuation issue, it requires monthly professional calibration, increasing the operational and maintenance burden, and is unable to adapt to dynamic dispensing needs. Most devices only support dispensing a fixed 30-person volume, while the actual number of dialysis patients fluctuates daily (±40%), resulting in wasted liquid (average daily waste volume of 15–20%) or insufficient reserves.

[0005] Concentrate quality assessment relies excessively on single-point conductivity testing. The conductivity sensor (CT1), affected by the highly corrosive nature of Liquid A, experiences instantaneous fluctuations of up to ±10%, and a single measurement fails to reflect the overall concentration distribution. Clinical data show that approximately 12% of dialysates qualified solely by conductivity (deviation ≤3%) still exhibit solute inhomogeneity, potentially causing hypotension or muscle cramps in patients. Furthermore, assessment of stirring effectiveness is lacking. Conventional equipment indirectly infers dissolution rate based on liquid level drop, but fails to account for concentration stratification caused by drug powder adhering to the wall (the residual rate on polysulfone barrel walls can reach 4.5%).

[0006] Existing equipment lacks adaptive optimization capabilities. Each unit in the liquid dispensing process (valves, pumps, sensors) operates independently, without a closed-loop feedback mechanism. For example, if the incoming water exceeds the specified value, there is no automatic compensation, requiring manual recalibration. Exceeding the conductivity limit only triggers an alarm, without any decision-making process to add powder. Furthermore, the piping design creates blind spots for cleaning. Traditional liquid dispensing tanks have numerous openings (≥6 ports), and residual liquid during storage becomes a source of microbial growth (with colony counts exceeding the specified limit by 8.3%). Disinfection relies on chemical reagents (such as peracetic acid), and residual detection increases maintenance hours by 30%.

[0007] In response to the above defects, this solution mainly solves the following problems: (1) Solve the problem of quantitative liquid preparation, achieve the function of liquid preparation with an accuracy of one dose, and effectively solve the problem of dialysate waste; (2) Optimize the water inlet method, improve the water inlet control accuracy, and reduce the water inlet error to the minimum; (3) Multi-dimensional judgment of the dialysate preparation quality, using the physical quantities of liquid level, conductivity, and density to comprehensively judge the dialysate concentration and minimize the error in the preparation process; (4) Improve the informationization and intelligence level of equipment and reduce the investment in management and maintenance personnel for centralized liquid supply. Summary of the Invention

[0008] The innovations of this invention lie in: flexible control of water intake based on the number of people undergoing dialysis; coordinated decision logic based on multiple physical quantities, including conductivity, liquid level, and density; and a real-time feedback compensation mechanism for liquid dispensing errors. Based on this, the present invention proposes the following solutions: In a first aspect, the present application provides a fully automatic precision comparison preparation method for dialysis concentrate, which is implemented in a liquid preparation box, which includes a water inlet valve, a stirring valve, and a stirring pump, and includes the following steps: Step (1): Calculate the target liquid level height based on the set liquid volume, the fixed volume of the cone bottom of the liquid distribution box, and the volume of the blind area measured by the liquid level sensor; Step (2): Control the water inlet valve to let water into the bottom of the liquid distribution tank, monitor the liquid level in real time, and close the water inlet valve when the target liquid level is reached; Step (3): open the stirring valve and stirring pump, so that the liquid is pumped out from the bottom of the liquid preparation tank and returned to the top of the liquid preparation tank through the circulating pipeline, and the stirring is continued for a preset stirring time; Step (4): the following detections are performed synchronously: a. Collect the conductance value data sequence after stirring is completed, calculate the average value and compare the deviation percentage with the standard conductance value; b. Compare the difference between the first liquid level value at the end of water inlet and the second liquid level value at the end of stirring; c. Obtain the offline density detection result; Step (5): when the following conditions are met simultaneously: the absolute value of the conductance deviation percentage is less than or equal to 6%; the difference between the first liquid level value and the second liquid level value is within a preset tolerance range; the density detection result is qualified, it is determined that the dialysis fluid preparation is qualified.

[0009] The core process includes: first, dynamically calculating the target liquid level height based on the set liquid preparation amount, which needs to deduct the fixed volume of the bottom of the liquid preparation tank and the blind area of the sensor measurement; then controlling the bottom water inlet to the target liquid level; then starting the circulating stirring to form vertical turbulent flow; after stirring is completed, the average value analysis of the conductance, the liquid level change detection and the offline density verification are performed synchronously; finally, the dialysis fluid preparation is qualified according to the three conditions of the conductance deviation rate, the liquid level difference tolerance and the density result. The unity of preparation precision and flexibility is realized, the problem of preparation waste is solved, and the safety of dialysis fluid is ensured through multi-source verification.

[0010] Preferably, in the step (1), when calculating the target liquid level height, the fixed volume of the conical region at the bottom of the liquid preparation tank and the volume of the non-measurable region below the zero point of the liquid level sensor need to be deducted.

[0011] In the calculation of the target liquid level, the fixed volume of the conical bottom of the liquid preparation tank and the volume of the non-measurable region below the zero point of the liquid level sensor need to be excluded. The beneficial effect is to eliminate the measurement error caused by the structure of the container, and to ensure that the water inlet amount calculation and the actual liquid preparation demand are strictly matched.

[0012] Preferably, in the step (2), after the water inlet valve is closed, a liquid level stability calibration operation is performed: liquid level fluctuation data is collected multiple times, the actual liquid level average value is calculated after removing the extreme values, and the actual water inlet amount is deduced.

[0013] After the water inlet is completed, the liquid level stability calibration is performed, the average liquid level is calculated by collecting fluctuation data multiple times and removing abnormal values, and the actual water inlet amount is deduced. The beneficial effect is to overcome the interference of water flow disturbance on measurement, and to provide an accurate benchmark for subsequent liquid preparation compensation.

[0014] Preferably, when the deviation between the actual water inflow and the set liquid distribution amount exceeds the allowable error, the target liquid level height of the subsequent water inflow control is automatically adjusted to compensate.

[0015] When the actual water inflow exceeds the set value, the target level of subsequent water inflow is automatically adjusted for dynamic compensation. The beneficial effect is to form a closed-loop self-optimization mechanism to maintain the accuracy and stability of the system in the long term.

[0016] Preferably, when calculating the conductance deviation percentage, the maximum and minimum values ​​in the collected data sequence need to be eliminated and the arithmetic mean value is calculated.

[0017] Conductivity analysis requires calculating the arithmetic mean of continuously collected data after removing the maximum and minimum values. This eliminates measurement distortion caused by transient interference and improves the reliability of concentration determination.

[0018] Preferably, the preset tolerance range is dynamically set according to the structural parameters of the liquid distribution box.

[0019] The acceptable range of liquid level change is dynamically set based on the geometric parameters of the liquid distribution tank. This has the beneficial effect of adapting to different equipment specifications and avoiding the risk of misjudgment caused by fixed thresholds.

[0020] Preferably, the priority for determining whether the liquid preparation is qualified is: first verify the liquid level difference, then verify the conductivity deviation, and finally verify the density result.

[0021] Quality verification is performed in the order of liquid level difference, conductivity deviation, and density. This results in stratified filtering of abnormalities, improving detection efficiency and reducing ineffective stirring energy consumption.

[0022] Preferably, during the circulating stirring, the liquid flows out from the bottom of the liquid distribution box and returns through the top to form a vertical turbulent flow.

[0023] During the circulation stirring, the liquid is pumped from the bottom of the liquid distribution tank to the top and then flows back, forming a vertical downward turbulent flow. The beneficial effect is to enhance the uniformity of the powder dissolution and avoid local concentration deviations.

[0024] Preferably, the cleaning procedure is automatically executed after the liquid preparation is completed, and a 360° clean flushing without dead angles is performed through the top spray device.

[0025] After the liquid is mixed, the top spray cleaning program is automatically triggered to achieve 360° coverage of the container inner wall. The beneficial effect is to eliminate the breeding ground for microorganisms and reduce the hospital's disinfection and maintenance costs.

[0026] In a second aspect, the present application further provides a fully automatic precision comparison preparation system for dialysis concentrate for implementing the method described in the first aspect, comprising: Liquid preparation container module: The liquid distribution box has a conical bottom and only a single fluid interface. The liquid level sensor and conductivity sensor are installed on the box wall, a spray device is configured on the top, and a water flow buffer structure is set at the bottom interface; Fluid Control Module: The water inlet pipe (including the water inlet valve) connected to the bottom interface of the liquid distribution tank, and the circulation pipe (including the stirring valve and stirring pump) connecting the bottom and top of the liquid distribution tank; Intelligent control module: A programmable controller with built-in liquid dosage calculation unit, multi-source data verification unit and qualification judgment unit; in: The liquid dispensing amount calculation unit is configured to output a target liquid level based on a set liquid dispensing amount, a container geometric parameter, and a sensor blind area volume; The multi-source data verification unit synchronously processes the conductivity mean, liquid level change value and density input signal; The qualification judgment unit performs a joint logical judgment of the conductivity deviation rate, the liquid level difference tolerance and the density result.

[0027] The beneficial effects of this program are as follows: (1) Combining theoretical calculations with computer-aided tools, and using PLC "digital" control, precise control of water inflow can be achieved; (2) Comprehensively determine the quality of dialysate using multiple dimensions including conductivity, liquid level, and density to ensure the safety of dialysis treatment; (3) Optimize the structural design, set up an electric discharge valve, and use concentrated liquid to push out the remaining water and air after cleaning and disinfection to ensure the cleanliness of the system; (4) Incorporate digital and intelligent control concepts to ensure the stability and advancement of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 Schematic diagram of the system framework of the present invention; Figure 2 is a flow chart of the method of the present invention; DETAILED DESCRIPTION

[0029] The present invention will be further described below in conjunction with the embodiments and accompanying drawings: like Figure 1 and 2As shown, this technology aims to provide a fully automated control method for dialysis concentrate preparation, addressing the low preparation accuracy issues encountered in related technologies. This system primarily involves a dialysis concentrate preparation system in a centralized liquid supply system, comprising: a water inlet device, including an inlet pipeline and a water inlet valve FV1; a liquid preparation device, including a liquid preparation tank, a stirring pump P1, a water tank outlet valve FV2, a stirring circulation valve FV3, and a stirring circulation pipeline. A liquid level sensor PT1 and a conductivity sensor CT1 are installed at appropriate locations on the sidewalls of the water tank. The main operating principle is: reverse osmosis purified water from the hemodialysis water production equipment enters the liquid preparation tank from the bottom of the water tank via the water inlet pipeline through valve FV1. When the liquid level reaches a set value, valve FV1 closes. Valves FV2 and FV3 are opened, and the stirring pump is activated. Pure water flows from the bottom of the liquid preparation tank back through the stirring circulation pipeline, where it is then added to the tank to form dialysate. When the stirring time reaches the set value, the stirring pump is shut off. Detect the dialysate conductivity value and liquid level height change value. When they meet the requirements, close the FV3 valve, start the stirring pump, and transport the dialysate to the liquid storage tank to complete the liquid preparation process.

[0030] The characteristics of this technology are as follows: In some embodiments, the pure water supply to the liquid distribution tank is typically top-inlet, and the pressure sensor PT1, which uses the differential pressure principle for liquid level measurement, is typically installed at the bottom side of the tank. This inflow of water from above exerts a certain amount of pressure on the bottom sensor, causing fluctuations in liquid level measurement and large errors in the distribution liquid concentration. In this technology, the liquid level sensor PT1 is moved to a suitable location on the side wall of the liquid distribution tank, and a bottom-inlet method is adopted. A water baffle is also installed at the bottom of the liquid distribution tank to mitigate the impact of inflow pressure on the liquid level sensor and improve water inflow accuracy.

[0031] In some embodiments, the liquid distribution tank has a large number of openings, and the inlet and outlet pipes are improperly installed. This can result in residual liquid at these inlets and outlets during the liquid storage or cleaning process. To reduce the number of openings in the liquid distribution tank and ensure a 360° clean, seamless storage and cleaning process, eliminating residual liquid, only one inlet and outlet is located at the conical bottom of the liquid distribution tank. During operation, the FV2 and FV3 valves automatically switch between water inlet and outlet.

[0032] In some embodiments, the amount of water in the liquid distribution tank is controlled by the liquid level height, which is calculated by the pressure difference sensor installed on the liquid distribution tank. The liquid level height converted from the required water inflow (i.e., the amount of water used for dialysis) must be calibrated before use. Once calibrated, subsequent use will be carried out according to the calibrated amount of water used for dialysis, regardless of the actual number of people on dialysis, resulting in waste of liquid distribution. This technology combines previous experience with theoretical calculation and automatic calibration technology to achieve precise control of different water inflows. The specific steps are as follows: (1) Set the dialysate dosage according to the number of people undergoing dialysis, that is, the water intake volume V1 that the system needs to control. It can be set on the touch screen, such as 1 to 50 servings (generally, one person consumes about 4 to 5L of dialysate for one dialysis session).

[0033] (2) Measure the radius R of the circular liquid dispensing barrel produced by 3D modeling and calculate the bottom area S of the liquid dispensing barrel.

[0034] (3) Since the bottom of the liquid distribution barrel is conical, the volume V2 of the cone bottom is calculated with the help of 3D software, and the volume V3 of the part below the liquid level sensor that cannot be measured is calculated. The volume of this part is the volume between the lower end of the sensor contact surface and the upper end of the cone bottom. The total volume is V2+V3.

[0035] (4) The PLC automatically calculates the liquid level height H1 to be controlled. The calculation formula is: H1 = (V1-V2-V3) / S; If the water inlet volume V1 is 150L, ​​the measured volume of the cone bottom of the water tank is V2, which is 6.9L. The part that the sensor cannot measure is V3, which is 34.9. The radius of the barrel R is 34.4cm. The calculated liquid level height H is: 29.33cm.

[0036] (5) When the liquid level in the distribution tank reaches the calculated control value, immediately close the FV1 water inlet valve. At this point, since the water has just been added, the liquid level may not be stable, and the actual value fluctuates around the control value H1. At this point, the system enters self-calibration mode: the PLC records a number every n seconds, continuously collecting data for m minutes. First, find the maximum and minimum values ​​of the m / n recorded data. After eliminating the maximum and minimum values, calculate the arithmetic mean h1 of these data. Calculate the actual water inflow v1 by reverse calculation based on the formula in step 4.

[0037] (6) Calculate the difference ΔV between the actual water inflow v1 and the controlled water inflow V1, ΔV = v1 - V1. When ΔV is within the set allowable error range, the water inflow is qualified. When ΔV exceeds the set allowable error range, the water inflow is unqualified, and the system alarm prompts, asking you to refill the water or pay attention to controlling the amount of dialysis drugs added.

[0038] (7) When ΔV exceeds the set allowable error value for three consecutive times, the PLC system executes the water inflow compensation optimization function. When ΔV<0, it means that the actual water inflow is small, and the PLC adjusts the control water inflow value according to the deviation, and the actual control value is V1+ΔV; when ΔV>0, it means that the actual water inflow is large, and the PLC adjusts the control water inflow value according to the deviation, and the actual control value is V1-ΔV; In addition to precisely controlling the water intake as one of the means to ensure the quality of the liquid preparation, this technology also incorporates the detection of the online conductivity value of the concentrated liquid in the liquid preparation tank, the change in the liquid level value before and after stirring, and the offline density value to comprehensively determine whether the dialysis fluid is qualified.

[0039] (1) After the stirring is completed, the PLC starts recording the conductivity CT1 data, recording one number every n seconds, and continuously collecting data for m minutes. First, calculate the maximum and minimum values ​​of the recorded m / n data. After eliminating the maximum and minimum values, calculate the arithmetic mean c1 of these data, and calculate the percentage difference between c1 and the set conductivity standard value C1. The formula is y=[(c1-C1) / C1]*100%. When the absolute value of y is less than 3%, the system determines that the liquid preparation is qualified. When the absolute value of y is within 3%~6%, the system determines that the liquid preparation is barely qualified and allows it to be used. When the absolute value of y is greater than 6%, the system determines that the liquid preparation is unqualified and needs to be re-prepared. In this case, it is possible that too little powder was added.

[0040] (2) Compare the liquid level value h1 after water inflow is completed and the liquid level value h2 after dosing and stirring is completed. If the difference between the two is within the set standard value, it means that the liquid preparation is qualified. If it exceeds the standard value, an alarm will be issued.

[0041] (3) After the liquid is prepared, the density of the dialysate is manually measured offline. When the density value is within the standard value range, it means that the liquid preparation is qualified.

[0042] (4) The priority order for judging whether the liquid preparation is qualified is: first judge whether the change in the liquid level value before and after stirring meets the requirements, which is the condition s1; then judge whether the conductivity value after stirring meets the requirements, which is the condition s2; and finally judge whether the density value meets the requirements, which is the condition s3.

[0043] (5) When conditions s1, s2, and s3 are all met, the liquid preparation is qualified. When conditions s2 and s3 are all met, the liquid preparation is qualified. If the remaining conditions are met, the preparation is unqualified.

[0044] The outstanding features of this technology are primarily used for the development of fully automated precision-controlled dosing in centralized liquid supply systems. The goal is to improve the flexibility and accuracy of dosing, replacing traditional empirical dosing operations with digital calculations. This technology also involves other new technologies that improve the efficiency of centralized liquid supply systems.

[0045] (1) Spray balls are installed on the top of the liquid distribution tank and the liquid storage tank to clean 360° without dead angles and reduce the growth of microorganisms; (2) A drain valve FV4 is provided after the microporous filter. The purpose is, firstly, to discharge the concentrated liquid that may be diluted by the pure water remaining in the microporous filter and its pipelines during liquid storage; secondly, to discharge the waste liquid during disinfection and cleaning out of the system as quickly as possible; (3) A liquid storage valve FV6 and a microporous cleaning valve FV5 are provided behind the microporous filter to realize automatic cleaning after liquid storage is completed, while ensuring that the liquid supply operation is not affected during cleaning; (4) All objects in contact with water, such as the liquid distribution box and microporous filter element, are made of corrosion-resistant, high-temperature-resistant, and sanitary materials; In another embodiment, the method can also be used for ion gradient monitoring and photocatalytic dialysate preparation. S10, calculating the target liquid level height based on the set liquid distribution volume, the fixed volume of the cone bottom of the liquid distribution tank, and the volume of the blind area measured by the liquid level sensor; The target liquid level height is calculated based on the set liquid distribution volume, the fixed volume of the cone bottom of the liquid distribution tank and the volume of the blind area measured by the liquid level sensor.

[0046] S20, control the water inlet valve to let water into the bottom of the liquid distribution tank, monitor the liquid level in real time and close the water inlet valve when the target liquid level is reached; Control the water inlet valve to let water into the bottom of the liquid distribution tank, monitor the liquid level in real time and close the water inlet valve when the target liquid level is reached.

[0047] S30, install a UV LED array (main wavelength 275nm) on the top of the liquid distribution box to emit a pulsed UV beam. This wavelength band specifically excites the vibration of the sodium bicarbonate molecular bond and promotes lattice dissociation; Unlike the fully automated precision comparison method for preparing dialysis concentrate, this method relies on the absorption of ultraviolet energy by drug powder, which is converted into heat energy. This creates a micron-scale thermal explosion effect on the particle surface: the sodium bicarbonate particles disintegrate rapidly due to the thermal explosion, and the sodium chloride crystals undergo crack penetration under the thermal gradient. Using acoustic feedback monitoring, a piezoelectric sensor array mounted on the chamber wall captures the sound signature of the drug powder disintegration in real time. When the acoustic signal's frequency domain energy is concentrated in the low-frequency band (indicating the disappearance of large particles), UV irradiation is automatically terminated.

[0048] S40, ion gradient verification, four sets of ion-selective sodium electrodes, potassium electrodes, calcium electrodes, and bicarbonate electrodes are deployed three-dimensionally on the inner wall of the box; Using ion spatial distribution mapping, a full tank scan is initiated after stirring has concluded. The upper liquid zone electrode group detects surface ion concentrations, the middle liquid zone electrode group establishes a longitudinal concentration gradient, and the bottom zone electrode group identifies precipitation risks. This generates an ion distribution cloud map, marking areas of abnormal accumulation. Combining liquid level data with the ion distribution map, if HCO⁻ ions accumulate at the bottom and the liquid level drops beyond the specified level, a warning of sodium bicarbonate precipitation is issued. A sudden increase in K⁺ ion concentration at the surface indicates inadequate dissolution.

[0049] S50. Based on the database of common complications in dialysis patients, a risk matrix was constructed, as shown in Table 1.

[0050] S60: After the liquid preparation is completed, inject medical ozone (concentration 3mg / L), start the ultraviolet array to generate free radicals, inject high-speed vortex water flow from the bottom interface to form a spiral rising cleaning force field, and carry the oxidation decomposition products out.

[0051] The above specific embodiments are only used to explain and illustrate the present application, and are not intended to limit the present application. Any changes and substitutions made to the present application without creative labor within the concept and protection scope of the claims shall fall within the protection scope of the present application.

Claims

1. A fully automatic precision comparison preparation method for dialysis concentrate, the method is implemented in a liquid distribution box, the liquid distribution box includes a water inlet valve, a stirring valve and a stirring pump, characterized in that: The following steps are involved: Step 1: Calculate the target liquid level height based on the set liquid volume, the fixed volume of the cone bottom of the liquid distribution tank, and the volume of the blind area measured by the liquid level sensor; Step 2: Control the water inlet valve to let water flow into the bottom of the liquid distribution tank, monitor the liquid level in real time, and close the water inlet valve when the target liquid level is reached; Step 3: Open the stirring valve and stirring pump to pump the liquid out from the bottom of the liquid distribution tank and return it to the top of the liquid distribution tank through the circulation pipeline, and continue stirring for the preset time; Step 4: Perform the following tests simultaneously: a. Collect the conductivity data sequence after stirring is completed, calculate the average value and compare it with the standard conductivity value to obtain the percentage deviation; b. Compare the difference between the first liquid level value at the end of water inflow and the second liquid level value at the end of stirring; c. Obtain offline density test results; Step 5: When both conditions are met: The absolute value of the conductivity deviation percentage is ≤6%; The difference between the first liquid level value and the second liquid level value is within a preset tolerance range; When the density test result is qualified, Determine whether the dialysis fluid preparation is qualified.

2. The method according to claim 1, characterized in that In step 1: When calculating the target liquid level height, the fixed volume of the conical area at the bottom of the liquid distribution tank and the unmeasurable volume below the zero point of the liquid level sensor need to be deducted.

3. The method according to claim 1, characterized in that In step 2: After closing the water inlet valve, perform the liquid level stability calibration operation: collect liquid level fluctuation data multiple times, calculate the actual liquid level average after eliminating extreme values, and reversely infer the actual water inflow.

4. The method according to claim 3, wherein: When the deviation between the actual water inflow and the set liquid dosage exceeds the allowable error, the target liquid level height of the subsequent water inflow control is automatically adjusted to compensate.

5. The method according to claim 1, wherein In step 4a: When calculating the conductance deviation percentage, it is necessary to eliminate the maximum and minimum values ​​in the collected data sequence and then calculate the arithmetic mean.

6. The method according to claim 1, characterized in that In the step 4b: The preset tolerance range is dynamically set according to the structural parameters of the liquid distribution box.

7. The method according to claim 1, characterized in that In step 5: The priority for determining whether the liquid preparation is qualified is: first verify the liquid level difference, then verify the conductivity deviation, and finally verify the density result.

8. The method according to claim 1, characterized in that In step 3: During circulating stirring, the liquid flows out from the bottom of the liquid distribution box and returns through the top to form vertical turbulence.

9. The method according to claim 1, characterized in that Also includes: After the liquid preparation is completed, the cleaning program is automatically executed, and 360° cleaning without dead angles is carried out through the top spray device.

10. A fully automatic precision comparison preparation system for dialysis concentrate for implementing the method of claim 1, characterized in that: include: Liquid preparation container module: The liquid distribution box has a conical bottom and only a single fluid interface. The liquid level sensor and conductivity sensor are installed on the box wall, a spray device is configured on the top, and a water flow buffer structure is set at the bottom interface; Fluid Control Module: The water inlet pipe (including the water inlet valve) connected to the bottom interface of the liquid distribution tank, and the circulation pipe (including the stirring valve and stirring pump) connecting the bottom and top of the liquid distribution tank; Intelligent control module: A programmable controller with built-in liquid dosage calculation unit, multi-source data verification unit and qualification judgment unit; in: The liquid dispensing amount calculation unit is configured to output a target liquid level based on a set liquid dispensing amount, a container geometric parameter, and a sensor blind area volume; The multi-source data verification unit synchronously processes the conductivity mean, liquid level change value and density input signal; The qualification judgment unit performs a joint logical judgment of the conductivity deviation rate, the liquid level difference tolerance and the density result.

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