Water production intelligent adjustment control system for hemodialysis equipment

Abstract

The utility model discloses a water production intelligent regulation control system for hemodialysis equipment, through real -time monitoring balancer liquid level, RO membrane pressure, temperature and water production electric conductance, combine liquid level change rate threshold value trigger frequency conversion pump dynamic frequency modulation, realize water production 2.0 4.5T / H wide range regulation. System introduces temperature compensation and membrane life coefficient optimization actual water production, and through moving average algorithm forecast demand, reduce the regulation frequency. After application, water supply pressure is stabilized at 4 0.2bar, and water saving is more than 30%, solve the energy waste and back pressure risk caused by fixed water production.

Description

Technical Field

[0001] This utility model relates to the field of water treatment technology for hemodialysis equipment, and more specifically, it relates to an intelligent regulation and control system for water production in hemodialysis. Background Technology

[0002] Currently, hemodialysis treatment requires drawing blood from the patient's body and exchanging substances with dialysate through a dialyzer to remove metabolic waste and excess water. Water purification equipment is an indispensable part of hemodialysis treatment; the stability of its water production and the quality of the water directly affect the effectiveness of dialysis and the patient's safety. However, most existing water purification equipment relies on simple manual adjustment of reflux and discharge shut-off valves, or simply controlling the pumps and valves based on feedback from permeate and concentrate flow rates to achieve the required water production. This simplistic and crude method makes it impossible for the water production to automatically and accurately adjust in a timely manner when operating conditions change, often resulting in either a constant or unstable production volume. Furthermore, the overall automation and intelligence levels of the equipment are relatively low, and the need for manual adjustment inevitably increases the workload and skill requirements of maintenance personnel. Failure to adjust water production in a timely manner also leads to problems such as wasted water and electricity.

[0003] Currently, the main working models on the market are as follows:

[0004] (1) Install a flow meter at the wastewater outlet of the reverse osmosis membrane to visually observe the change in the amount of reverse osmosis wastewater. Manually adjust the production water volume based on the amount of wastewater. For example, patent CN201520738921.8 proposes a laboratory-use adjustable flow ultrapure water machine.

[0005] (2) When the actual number of hospital beds is lower than the designed number of beds, and patients are getting on and off the dialysis machine one after another, the designed operating water production volume far exceeds the actual demand of patients, wasting energy and water resources. For example, CN202022137511.1 proposed a water production balance system for a water production equipment for hemodialysis, which uses a two-stage reverse osmosis membrane (first-stage RO + second-stage RO) to improve water quality, but the recovery rate is fixed (≤50%), and it is impossible to dynamically adjust the concentrated water discharge according to the raw water quality, resulting in water waste.

[0006] (3) The equipment is equipped with a flow sensor to monitor the flow rate of permeate and concentrate in real time, and automatically adjusts the working status of the pump or valve through a feedback mechanism to maintain a stable flow rate.

[0007] In view of the shortcomings of existing technologies in optimizing water production efficiency and recovery rate, dynamic adjustment of water production, life and maintenance of key components, and lack of intelligence and predictive capabilities, this utility model aims to develop a method and system for intelligent regulation and control of water production with multi-dimensional and multi-condition capabilities and predictive functions. Utility Model Content

[0008] This utility model solves the following problems:

[0009] (1) Solve the problem of water and electricity waste caused by the designed water production capacity far exceeding the actual water consumption required;

[0010] (2) To solve the problem of unstable water supply pressure when water consumption fluctuates greatly during the process of patients getting on and off the equipment;

[0011] (3) Solve the problem of abnormal back pressure in water supply pipelines caused by water supply volume being much greater than water consumption;

[0012] (4) Solve the problems of single water production regulation conditions, single regulation method, poor regulation performance, and simple control algorithm;

[0013] (5) Solve the problem of low levels of equipment automation, intelligence and informatization, and large amount of manual labor.

[0014] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0015] A smart water production regulation system for hemodialysis equipment, comprising:

[0016] The data acquisition module includes: a level sensor installed in the balancer, pressure sensors installed at the inlet and outlet of the secondary reverse osmosis membrane, a temperature transmitter for monitoring the feed water temperature, a conductivity data acquisition instrument for detecting the conductivity of the permeate, and a flow sensor for measuring the permeate flow rate.

[0017] The central controller, connected to the data acquisition module, is internally configured with: a dynamic compensation unit, used to perform temperature compensation and membrane life decay compensation on the standard permeate flow rate based on the inlet water temperature and the cumulative usage time of the reverse osmosis membrane, and output the compensated actual reference permeate flow rate; an adjustment enable decision unit, used to generate adjustment enable level signals based on liquid level signals, pressure signals, and preset liquid level thresholds and pressure thresholds; and a prediction and pre-control unit, used to generate frequency prediction values ​​based on historical permeate flow rate and pump frequency data when the system is stable.

[0018] The execution module includes: a secondary water production variable frequency pump controlled by the central controller, the operating frequency of which is driven by an adjustment enable level signal and / or a frequency prediction value; and a secondary water production fixed frequency pump controlled by the central controller, the start / stop state of which is driven by an adjustment enable level signal.

[0019] Preferably, the dynamic compensation unit includes: a temperature compensation submodule, which has built-in data on the correspondence between reverse osmosis membrane permeate flow and temperature, and outputs a temperature compensation coefficient based on the deviation between the real-time inlet water temperature and 25 degrees Celsius; and a membrane attenuation compensation submodule, which outputs a membrane lifetime attenuation coefficient based on the ratio of the initial conductivity of the reverse osmosis membrane to the real-time conductivity.

[0020] Preferably, the prediction and control unit includes: a data sampling circuit that records the water production flow rate and the operating frequency of the secondary water production variable frequency pump at fixed time intervals; and a moving average calculation circuit that calculates the frequency prediction value by averaging multiple sets of frequency data collected within a continuous statistical period according to equal weights.

[0021] Preferably, the fixed time interval is one minute, the continuous statistical duration is two hours, the number of groups of multiple frequency data is six, and the number of data items for equal weight average calculation is four.

[0022] Preferably, the regulation enable decision unit includes: a liquid level comparator, which outputs a regulation enable level signal when the liquid level value is between a low liquid level threshold and a high liquid level threshold, and the absolute value of the liquid level change rate exceeds a preset change rate threshold; and a pressure comparator, which outputs a regulation enable level signal when the product water pressure value exceeds the range of 0.5 to 1.2 times the standard pressure value.

[0023] This invention's intelligent control system monitors in real-time the primary and secondary transmembrane pressures, balancer level, conductivity, permeate flow rate, secondary variable frequency pump operating frequency, inlet water temperature, and reverse osmosis membrane usage time during system operation, based on the number of patients and dialysis treatment needs. The central controller collects this data, using balancer level and transmembrane pressure as primary factors, and calculates their rate of change. Secondary factors such as conductivity, inlet water temperature, and reverse osmosis membrane usage time are considered to calculate a reference value for the standard permeate flow rate. A high-performance central controller is used to intelligently adjust the permeate flow rate in multiple dimensions and under multiple conditions. Simultaneously, the moving average method from a time-series prediction algorithm is introduced to predict the required permeate flow rate within a certain future timeframe based on relevant historical data, alleviating the problem of frequent adjustments and achieving dynamic, precise, and intelligent adjustment of permeate flow rate and constant pressure water supply, ensuring the system operates under optimal conditions.

[0024] This utility model has the following beneficial effects:

[0025] (1) Intelligently adjust the water production to meet the dialysis water needs of patients under different dialysis environments and improve the efficiency of water resource utilization;

[0026] (2) Through intelligent control, energy consumption is reduced and equipment utilization efficiency is improved;

[0027] (3) Reduce the risk of pressure buildup in water supply pipelines and avoid water leakage due to high pressure operation;

[0028] (4) Through the coordinated operation of the pressure transmitter and the frequency converter, ensure the stable water supply of the dialysis machine, and improve the dialysis treatment effect and safety; Brief Description of the Drawings

[0029] Figure 1 is the system schematic diagram provided by the present utility model;

[0030] Figure 2 is the method flow chart provided by the present utility model;

[0031] Figure 3 is the flow chart provided by the specific embodiment of the present utility model. Detailed Description of the Embodiment

[0032] The present disclosure will be further described below in conjunction with the drawings and embodiments.

[0033] It should be noted that the following detailed descriptions are all illustrative and intended to provide further explanations for the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present application belongs.

[0034] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0035] In the present disclosure, terms such as "upper", "lower", "left", "right", "front", "rear", "vertical", "horizontal", "side", "bottom", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. They are only relational terms determined for the convenience of describing the structural relationship of each component or element of the present disclosure and do not specifically refer to any component or element of the present disclosure. It cannot be understood as a limitation to the present disclosure.

[0036] In the present disclosure, terms such as "fixed connection", "connected", "connected" should be understood in a broad sense, indicating that it can be a fixed connection, an integral connection or a detachable connection; it can be directly connected or indirectly connected through an intermediate medium. For those related scientific research or technical personnel in the field, the specific meaning of the above terms in the present disclosure can be determined according to specific circumstances and cannot be understood as a limitation to the present disclosure.

[0037] Refer Figure 1 and Figure 2As shown, an intelligent regulation and control method for water production in hemodialysis includes step S1: obtaining the liquid level height value of the balancer, and preset three liquid level thresholds and change rates according to the total volume of the balancer: low liquid level, medium liquid level and high liquid level, as well as Δfast, Δmild and Δnone.

[0038] Step S2: Determine whether the liquid level in the balancer is above the low liquid level or below the high liquid level. If so, calculate the rate of change of liquid volume in the balancer according to the formula △V=△V1 / △T, where △V1 represents the amount of change of liquid volume in the balancer and △T represents the time interval.

[0039] Step S3: Set different adjustment enable levels for intelligent water production adjustment according to different situations. When the balancer liquid level is greater than the high liquid level or less than the low liquid level, the adjustment enable level is 0, indicating that intelligent adjustment should be exited; when the balancer liquid level is less than the high liquid level but greater than the low liquid level, the adjustment enable level is 1 or 2, indicating that intelligent adjustment should be turned on.

[0040] Step S4: When the adjustment enable level in step S3 is 1 or 2, determine the difference between the actual pressure value of the pressure sensor and the preset standard value. If the actual pressure value of the pressure sensor is less than the preset standard value and the operating frequency of the secondary variable frequency pump is less than the preset first threshold frequency, execute the frequency increase action of the secondary variable frequency pump; if the actual pressure value of the pressure sensor is less than or greater than the preset standard value and the operating frequency of the secondary variable frequency pump is greater than the preset second threshold frequency, execute the frequency decrease action of the secondary variable frequency pump; otherwise, execute the frequency increase action of the secondary variable frequency pump.

[0041] After the frequency adjustment completion signal is output in step S4, the following steps are also included:

[0042] Step S5: When the adjustment enable level in step S3 is 1 or 2, the standard permeate flow rate is dynamically corrected based on the feed water temperature and reverse osmosis membrane usage time to obtain the actual reference permeate flow rate. The calculation formula is as follows:

[0043] Q 实 =Q 标 ×k1×k2

[0044] Where k1 is the temperature compensation coefficient, k2 is the membrane lifetime decay coefficient, and Q 实 Q represents the actual water production. 标 Standard water production rate;

[0045] Step S6: Using the actual reference water production volume as the target value, adjust the operating frequency of the secondary variable frequency pump and the start / stop status of the secondary fixed frequency pump to make the water production flow match the water demand.

[0046] Step S7, after the device stabilizes, and |Q 实 -Q 标 | / Q标 When the percentage is ≤5%, the permeate flow rate and the operating frequency of the secondary variable frequency pump are recorded at fixed sampling intervals, resulting in an observation sequence of y1,…,y t Divide the sequence into t groups, and calculate the N-term moving average of the pump frequency at the end of each group. The calculation formula is as follows:

[0047]

[0048] by As the predicted value of pump frequency for the next period Pre-adjusting the secondary variable frequency pump to The calculation formula is as follows:

[0049]

[0050] Based on the above formula, the operating frequency corresponding to the water production demand in the next stage can be calculated, so as to reduce the frequent intelligent adjustments caused by individual external factors.

[0051] This utility model mainly relates to an intelligent water production regulation and control system, which includes a balancer level LT1, a secondary power frequency pump PUMP3, a secondary water production variable frequency pump PUMP4, a conductivity data acquisition instrument CT2, a temperature transmitter TT, pressure transmitters PT3 and PT4, and a flow sensor FI3 in a water production equipment for hemodialysis. Its key feature is the establishment of a high-performance central controller. This central controller collects process physical quantities such as pressure, flow rate, temperature, level, and conductivity, performs specific calculations, and converts these into control signals to control the start, stop, and operating frequency of the two secondary water production pumps, thereby achieving intelligent regulation of water production.

[0052] In hemodialysis water purification equipment, the main function of the balancer is to balance the influent and effluent flow rates, maintaining the liquid level at a constant value. Since the influent and effluent flow rates are not linearly related, the balancer level will change when the water consumption suddenly increases or decreases. Therefore, the change in water consumption can be predicted based on the change in liquid level over a certain period. The specific method is as follows: A liquid level sensor LT1 is installed inside the balancer. An analog-to-digital converter converts the 4-20mA analog signal of the liquid level into a digital signal, which is then transmitted to the central controller. The central controller calculates the liquid volume within the balancer based on the liquid level signal and performs timed calculations to determine the rate of change in the liquid volume within the balancer. This rate of change determines the change in dialysis water consumption over a certain period, serving as the control enable condition for intelligent regulation. The steps of the control method implemented by the central controller are as follows:

[0053] (1) The central controller first sets three reference values for the level H of the balancer, namely, low level, medium level, and high level, denoted as H_low, H_mid, and H_high respectively. Their relationship is H_low < H_mid < H_high. Then, according to these three level values, four regions can be divided: below the low level, between the low level and the medium level, between the medium level and the high level, and above the high level. Since the situations below the low level and above the high level need to be avoided during normal two-stage water production, the central controller mainly calculates the rate of change of the liquid volume in the region above the low level and below the high level. Three criteria can be established based on the rate of change: fast change, slow change, and basically no change, denoted as △_fast, △_slow, and △_none respectively. Their relationship is △_fast > △_slow > △_none.

[0054] (2) When the level of the balancer is in the region above the low level and below the high level, at every certain time interval △T, the central controller calculates the liquid volume V in the balancer according to the signal of the level sensor, and simultaneously calculates the change amount △V1 of the liquid volume in the balancer within the time interval △T and the rate of change of the liquid volume in the balancer △V, where △V = △V1 / △T.

[0055] (3) The central controller implements control over the intelligent regulation of the water production according to the following situations, and sets different regulation enable levels according to different situations.

[0056] (3.1) When H < H_low, it indicates that the water consumption is extremely large and the water inflow of the balancer cannot keep up. At this time, to protect each water production pump, stop the water production pump and exit the intelligent regulation. The regulation enable level is 0.

[0057] (3.2) When H > H_high, it indicates that the water consumption is extremely small or almost no water consumption. Exit the intelligent regulation. The regulation enable level is 0.

[0058] (3.3) When H_low < H < H_high and △V < 0, |△V| ≥ △_none, it indicates that the overall water consumption is stable and the water inflow and water consumption tend to be balanced. The intelligent regulation can be started. The regulation enable level is 1; (3.4) When H_low < H < H_high and △V < 0, |△V| ≥ △_slow, it indicates that the overall water consumption is gradually increasing instantaneously. Start the intelligent regulation. The regulation enable level is 2.

[0059] (3.5) When H_low < H < H_high and △V < 0, |△V| ≥ △_fast, it indicates that the overall water consumption is increasing rapidly instantaneously. Start the intelligent regulation. The regulation enable level is 2.

[0060] (3.6) When H_low < H < H_high and △V > 0, |△V| ≥ △_slow, it indicates that the overall water consumption is gradually decreasing instantaneously. The intelligent regulation can be started. The regulation enable level is 1.

[0061] When (3.7)H low < H < H high and △V > 0, and |△V| ≥ △ fast, it indicates that the overall water consumption is rapidly decreasing instantaneously, and the intelligent adjustment is activated with an adjustment enable level of 2;

[0062] The liquid volume change rate in the balancer is used as the enabling condition for the intelligent adjustment of water production. When the adjustment enable level is 0, the intelligent adjustment is not executed. When the adjustment enable level is 1, the intelligent adjustment is selectively executed according to the actual situation. When the adjustment enable level is 2, the intelligent adjustment must be executed.

[0063] In addition to the liquid level change rate of the balancer, the change rate of the water production pressure is also used as the execution condition for the intelligent adjustment of water production. When the water consumption is relatively small, such as when the equipment still maintains the previous water production, the pipeline pressure will rise to 2 - 3 times the preset pressure, and the back pressure on the water production side of the second-stage reverse osmosis membrane will far exceed the allowable value. When the water consumption increases, the water volume in the pipeline decreases and the pressure decreases accordingly. Therefore, detecting the water production pressure can directly reflect the change in water consumption and can be used as the execution condition for the intelligent adjustment of water production. The specific method is as follows: A pressure sensor PT3 and a pressure sensor PT4 are respectively installed at the inlet and outlet positions of the second-stage reverse osmosis membrane. The analog quantity signal of 4 - 20 mA pressure is converted into a digital quantity signal through an analog-to-digital conversion module and transmitted to the central controller. At the same time, the operating frequency of the second-stage variable-frequency pump PUMP4 is transmitted to the central controller. The central controller uses the change rate of the pressure across the membrane and the operating frequency of the variable-frequency pump as the execution condition for the intelligent adjustment of water production. The steps of the method controlled by the central controller are as follows:

[0064] (1) Set the standard value of the pressure before the membrane. When the actual pressure is between 0.5 and 1.2 times the standard value, the intelligent adjustment can be activated with an adjustment enable level of 1;

[0065] (2) Set the standard value of the pressure of the water supply pipeline after the membrane, denoted as "P standard". The central controller collects the actual pressure PT4 value, denoted as "P actual", and the central controller collects the operating frequency value of the second-stage variable-frequency pump PUMP4, denoted as "F". The control relationship among the three is as follows:

[0066] (2.1) P 实 < P 标 , F < 50HZ, indicating that the water consumption has increased instantaneously, and the operating frequency of the second-stage variable-frequency pump PUMP4 will increase to make P actual = P standard;

[0067] (2.2) P 实 < P 标 , F = 50HZ, indicating that the water consumption has reached the maximum instantaneously, and the operating frequency of the second-stage variable-frequency pump PUMP4 has reached the maximum;

[0068] (2.3) P 实 > P 标, F > 25HZ indicates that the water consumption decreases instantaneously, and the operating frequency of the secondary variable-frequency pump PUMP4 will decrease to make Pactual = Pstandard;

[0069] (2.4)P 实 >P 标 , F < 25HZ indicates that the water consumption is at its minimum instantaneously. The secondary variable-frequency pump PUMP4 operates at the lower limit frequency. At this time, the secondary industrial-frequency pump PUMP3 is shut down, and the operating frequency of the secondary variable-frequency pump PUMP4 is increased to make P 实 =P 标 ;

[0070] The conditions affecting the water production volume, in addition to the water production pressure, are also related to the inlet water temperature and the usage time of the reverse osmosis membrane. The control factors of the inlet water temperature and the usage time of the reverse osmosis membrane are also added to this intelligent water production volume regulation method. Since this water treatment equipment for hemodialysis is equipped with a water temperature compensation device, the temperature is generally controlled at about 25°C. According to the relationship between the water production volume of the reverse osmosis membrane and the temperature, the consideration of the temperature system is added to the control method. For example, the water production temperature coefficient k1 at the standard 25°C is used as the standard reference value for the water production flow. The usage time of the reverse osmosis membrane is directly proportional to the conductivity of the produced water. The longer the usage time, the greater the conductivity value of the produced water. The relationship coefficient K2 between the usage time of the membrane and the conductivity of the produced water is added to the control method. The standard production volume is represented by "Qstandard", and the actual production volume is represented by "Qactual". Then the reference value for the intelligent regulation of the water production volume is:

[0071] Since the water production volume may remain stable within a certain value range for a long time during the stable water production of the system, in order to eliminate the adjustment variables caused by an accidental factor. A method based on historical data to predict the operating state requirements within a certain period in the future is also added to this control method. The specific method is: when the system is producing water normally, start to circularly count the water production flow and the corresponding operating frequency.

[0072] (1) Record a data for the water production flow every n minutes, continuously count for m hours, and then take the average value of these data.

[0073] (2) Compare the average value of the water production flow with the standard value. When the difference between the two is less than 5%, it indicates that the water production and water consumption of the entire system are stable, and the basic trend of the predicted target water production volume fluctuates around the standard value. A pre-control model of the operating frequency corresponding to the target water production volume can be established using the simple moving average method.

[0074] (3) Establish a prediction model for the operating frequency. First, divide the 60m / n groups of operating frequencies recorded into t equal parts. Let the observation sequence be y1,…,, and take the number of terms N for the moving average < t. The calculation formula for the simple moving average value at one time is:

[0075]

[0076] Established operating frequency model:

[0077]

[0078] The operating frequency corresponding to the water production demand in the next stage can be calculated based on the above formula, so as to reduce frequent intelligent adjustments caused by individual external factors. When the changes in water production and operating frequency data are greater than 5%, it indicates that the external water consumption fluctuates greatly, and the system will intelligently adjust the water production in real time to ensure the stability of water use.

[0079] Example

[0080] like Figure 3 As shown, taking a hemodialysis device with a rated water production capacity of 3.6T / H (water temperature 25℃) as an example, the pure water pipeline is made of stainless steel, with a length of 300m, a diameter of DN32, and an inlet water temperature of about 25℃.

[0081] After activating the two-stage water production mode, when the balancer level is above the middle level, first open the electric valve FV3 to start the first-stage variable frequency pump PUMP2 for low-pressure flushing. When the flushing time reaches the set time, close the electric valve FV3, and the first-stage variable frequency pump PUMP2 remains in its current state, ending the high-flow low-pressure flushing. Entering normal two-stage water production mode, start the first-stage variable frequency pump PUMP1, and after a 5-second delay, start the second-stage variable frequency pump PUMP4, and after a 2-second delay, start the second-stage fixed-frequency pump PUMP3. Adjust diaphragm valves 101, 201, and 202 to a certain opening degree to ensure a reverse osmosis membrane pressure of 8-10 bar. Monitor the second-stage permeate pressure PT4, which should be constant at 4 bar. After the system runs stably for a period of time, record the second-stage permeate flow rate FI3 and the operating frequency of the second-stage variable frequency pump PUMP4. Monitor the balancer LT1 level and determine whether to activate intelligent regulation based on the rate of change of liquid volume within the balancer. Monitor the second-stage permeate pressure PT4 and determine whether to activate intelligent regulation based on the rate of change of pressure. By intelligently adjusting the operating frequency of the secondary variable frequency pump PUMP4 and the operating status of the secondary fixed frequency pump PUMP3, the water supply pressure is kept stable at 4 bar, the water production flow rate is within the standard range (2.4±0.2T / H~4.5±0.2T / H), and the conductivity of the secondary product water is <10μS / cm.

[0082] (1) During the equipment commissioning phase or before patients use the machine, the consumption of pure water for hemodialysis is minimal. If the equipment maintains a water production rate of 3.6T / H, the pipeline pressure will rise to 2-3 times the preset pressure, and the back pressure on the water production side of the secondary reverse osmosis membrane will far exceed the allowable value, leading to a decrease in equipment stability and an increase in the risk of pipeline leakage. By monitoring the fluctuation of water consumption, the water production rate can be reduced to about 2.0T / H by adjusting the pump frequency to maintain stable pipeline pressure and no back pressure on the water production side.

[0083] (2) When the dialysis room is running at full capacity, or when the dialysis machine is in the disinfection stage (the water demand increases by 20% compared to the normal dialysis stage), in order to ensure the stability of the water supply pipeline pressure, the system is operated at a higher frequency, and the water production is increased by 25% on the basis of the rated water production to meet the supply demand and avoid the dialysis machine from running out of water or low pressure alarm.

[0084] (3) After the water production system stabilizes, record the water production and operating frequency. Data is collected every minute for 2 consecutive hours. The average of the 120 water production data points is calculated. When the value is between 3.42 and 3.78 T / H (with the rated water production of 3.6 T / H as the standard value), it indicates stable water production, and the approximate operating frequency for the next cycle can be predicted. Using a moving average, the 120 operating frequencies are divided into 6 equal parts, and the average is calculated for every 20 frequencies. The number of averages is 4. The operating frequency pattern for the 7th 20-minute period is shown in the table below:

[0085]

[0086] (4) Automatically collect and store equipment operation data, establish a large database of specific operating conditions for each piece of equipment, compare and analyze real-time operation data with the database, and automatically adjust in case of abnormality to ensure that the equipment operates in the best condition.

[0087] (5) In summer, when the temperature is high, a temperature transmitter is installed on the secondary product water side to monitor the outlet water temperature. When the temperature exceeds the temperature that the human body can withstand (which can be set), the system will automatically discharge from FV14 until the temperature drops below the set lower limit temperature to ensure the safety of patients undergoing dialysis.

[0088] The embodiments described above are merely preferred solutions of this utility model and are not intended to limit this utility model in any way. Other variations and modifications are possible without departing from the technical solutions described in the claims.

Claims

1. An intelligent water production regulation and control system for hemodialysis equipment, characterized in that, include: The data acquisition module includes: a level sensor installed in the balancer, pressure sensors installed at the inlet and outlet of the secondary reverse osmosis membrane, a temperature transmitter for monitoring the feed water temperature, a conductivity data acquisition instrument for detecting the conductivity of the permeate, and a flow sensor for measuring the flow rate of the permeate. The central controller is connected to the data acquisition module and is internally configured with a dynamic compensation unit, which is used to perform temperature compensation and membrane life decay compensation on the standard permeate flow rate based on the inlet water temperature and the cumulative usage time of the reverse osmosis membrane, and outputs the compensated actual reference permeate flow rate. The regulation enable decision unit is used to generate regulation enable level signals based on liquid level signals, pressure signals, and preset liquid level thresholds and pressure thresholds; the prediction and control unit is used to generate frequency prediction values ​​based on historical water production flow and pump frequency data when the system is stable. The execution module includes: a secondary water production variable frequency pump controlled by the central controller, the operating frequency of which is driven by an adjustment enable level signal and / or a frequency prediction value; and a secondary water production fixed frequency pump controlled by the central controller, the start / stop state of which is driven by an adjustment enable level signal.

2. The system according to claim 1, characterized in that: The dynamic compensation unit includes: a temperature compensation submodule, which has built-in data on the relationship between reverse osmosis membrane permeate flow and temperature, and outputs a temperature compensation coefficient based on the deviation between the real-time inlet water temperature and 25 degrees Celsius; and a membrane attenuation compensation submodule, which outputs a membrane lifetime attenuation coefficient based on the ratio of the initial conductivity of the reverse osmosis membrane to the real-time conductivity.

3. The system according to claim 1, characterized in that: The prediction and control unit includes: a data sampling circuit that records the water production flow rate and the operating frequency of the secondary water production variable frequency pump at fixed time intervals; and a moving average calculation circuit that calculates the frequency prediction value by averaging multiple sets of frequency data collected within a continuous statistical period according to equal weights.

4. The system according to claim 3, characterized in that: The fixed time interval is one minute, the continuous statistical duration is two hours, the number of groups of multiple frequency data is six, and the number of data items for the equal weighted average calculation is four.

5. The system according to claim 1, characterized in that: The regulation enable decision unit includes: a level comparator, which outputs a regulation enable level signal when the level value is between a low level threshold and a high level threshold, and the absolute value of the level change rate exceeds a preset change rate threshold; and a pressure comparator, which outputs a regulation enable level signal when the product water pressure value exceeds 0.5 to 1.2 times the standard pressure value.

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