Regulation and control method for stably improving water quality of water produced by reverse osmosis system of power plant

Abstract

The invention discloses a regulation and control method for stably improving the water quality of water produced by a reverse osmosis system of a power plant, and relates to the field of water quality regulation and control, which comprises the following steps: configuring a water inlet flow regulation device, performing initial setting, configuring the position of an online sensor, performing data acquisition, setting judgment rules of turbidity, differential pressure and transmembrane pressure difference, and determining the water quality. And configuring a flocculant adding device and adding control logic, configuring a backwashing and adding linkage control state machine, and carrying out data smoothing, trend analysis and self-adaptive threshold adjustment. When the water quality of the raw water fluctuates for a short time or the pollution load is increased, dynamically adjusting the water inlet flow, the backwashing intensity and the flocculant adding concentration based on parameters such as turbidity, pollution index, conductivity and pressure difference which are acquired by an online sensor in real time; and meanwhile, the concentrated water reflux proportion and the high-pressure pump frequency are automatically corrected by continuously calculating the desalting rates of the first-stage and second-stage reverse osmosis devices, so that the running state of the membrane component is kept in an optimal interval.

Description

Technical Field

[0001] This invention relates to the field of water quality control, and in particular to a method for steadily improving the quality of permeate from a reverse osmosis system in a power plant. Background Technology

[0002] In large-scale thermal power plants, the reverse osmosis system is a crucial component in boiler feedwater preparation, directly impacting the safe and stable operation of the unit. A typical reverse osmosis system consists of units such as a dual-media filter, ultrafiltration unit, primary reverse osmosis unit, secondary reverse osmosis unit, and mixed ion exchanger. It is used to purify raw water through multiple stages to obtain high-purity demineralized water. With the expansion of power plant scale and the increasing demands for water quality, reverse osmosis systems not only need to operate stably under high loads for extended periods but also need to cope with complex operating conditions such as raw water quality fluctuations, contaminant shock loads, and membrane module performance degradation. Therefore, real-time acquisition, analysis, and control of operating parameters and water quality indicators throughout the entire process is a vital technical direction for ensuring the stability of product water quality.

[0003] Existing reverse osmosis systems in power plants primarily operate using fixed procedures and periodic maintenance, lacking the ability to dynamically identify water quality fluctuations and contamination states. This can easily lead to two problems: First, when raw water turbidity, SDI, or salinity concentrations increase temporarily, the system cannot adjust the feed water flow rate, flocculant dosage, and backwashing strategy in a timely manner. This allows particulate matter or colloidal impurities to penetrate the pretreatment unit, increasing the risk of membrane fouling and affecting the stability of permeate water quality. Second, when the desalination rate of the first and second stage reverse osmosis units decreases or the permeate conductivity fluctuates, there is a lack of real-time optimization methods for the concentrate recirculation ratio and high-pressure pump frequency. The delayed adjustment of operating parameters may cause deterioration of the membrane module's desalination performance, affecting the effluent quality of the downstream mixed ion exchanger. Summary of the Invention

[0004] The purpose of this invention is to address the shortcomings of existing technologies by providing a method for regulating and improving the stable quality of permeate water in a power plant reverse osmosis system. This method aims to establish a unified data acquisition mechanism for water quality and operating parameters throughout the entire process by configuring online sensors in each treatment unit of the reverse osmosis system. Combined with a multivariate feedback control model, it achieves dynamic optimization and adjustment of parameters such as influent flow rate, filter media backwashing frequency, flocculant dosage, concentrate recirculation ratio, high-pressure pump frequency, and the regeneration cycle of the mixed ion exchanger. Through trend analysis and adaptive threshold correction of indicators such as turbidity, fouling index, conductivity, and desalination rate, it effectively mitigates the impact of pollutants on membrane elements and resin layers, maintaining the system operation within a stable range, thereby significantly improving the stability of permeate water quality and the overall reliability of the system operation.

[0005] Therefore, this application provides a method for regulating and improving the quality of permeate from a power plant reverse osmosis system, comprising the following steps:

[0006] Step S100: Configure the water treatment unit, obtain high-purity demineralized water, collect the operating parameters of the reverse osmosis system, and monitor them.

[0007] Step S200: Configure the influent flow rate regulating device and perform initial settings; configure the online sensor position and perform data acquisition; set the judgment rules for turbidity, differential pressure and transmembrane pressure difference; configure the flocculant dosing device and dosing control logic; configure the backwash and dosing linkage control state machine; and perform data smoothing, trend analysis and adaptive threshold adjustment.

[0008] Step S300: Configure stable operation control of primary reverse osmosis, configure concentrate reflux ratio adjustment, and configure high-pressure pump frequency optimization.

[0009] Step S400: Configure secondary reverse osmosis operation regulation and conductivity closed-loop control, configure product water homogenization device and dynamic reflux pipeline, and set product water homogenization and system dynamic balance control.

[0010] Step S500: Set the operating configuration of the mixed ion exchanger, perform mixed ion exchanger operating status determination, set the trigger for the mixed ion exchanger regeneration program, configure parallel switching to ensure continuous water supply, and configure mixed ion exchanger life management and regeneration cycle optimization.

[0011] Step S600: Configure a unified acquisition mechanism for water quality and operating parameters throughout the entire process, configure a multivariate feedback control model, set automatic optimization of reagent dosage and membrane flushing cycle, configure concentrate recirculation and dynamic balance strategies, and form a stable and controllable operating state and alarm feedback.

[0012] As a preferred embodiment of the present invention, step S100 specifically includes:

[0013] Step S100.1: Configure the water treatment unit, obtain high-purity demineralized water, collect the operating parameters of the reverse osmosis system, and monitor them.

[0014] In the power plant's water treatment system, tap water is first obtained through the city's water supply network. The obtained tap water enters a clear water tank located within the plant area. The clear water tank is used for preliminary storage and buffering of the incoming tap water. The tap water is then pressurized from the clear water tank by a chemical feed pump located at the outlet of the clear water tank. The pressurized tap water is then continuously transported to the subsequent water treatment units.

[0015] In the specific process of the water treatment unit, tap water sequentially enters a dual-media filter, an ultrafiltration unit, a first-stage reverse osmosis unit, a second-stage reverse osmosis unit, and a mixed ion exchanger. The dual-media filter is composed of quartz sand filter media and anthracite filter media, used to remove suspended solids and some colloidal impurities in the water. The ultrafiltration unit uses hollow fiber ultrafiltration membranes to intercept particles and bacteria. The first-stage reverse osmosis unit uses spiral wound membrane elements to initially remove dissolved salts. The second-stage reverse osmosis unit further desalinates the water produced by the first-stage reverse osmosis unit. The mixed ion exchanger is filled with a mixture of strong acidic cation exchange resin and strong basic anion exchange resin to remove residual ions and obtain high-purity desalinated water.

[0016] As tap water flows sequentially through a dual-media filter, an ultrafiltration device, a primary reverse osmosis device, a secondary reverse osmosis device, and a mixed ion exchanger, key water quality parameters are collected and monitored in real time.

[0017] Online sensors are installed at the inlet of the dual-media filter, at the outlet of the ultrafiltration unit, at the inlet and product water ends of the first-stage reverse osmosis unit, at the inlet and product water ends of the second-stage reverse osmosis unit, and at the outlet of the mixed ion exchanger.

[0018] Online sensors are used to collect turbidity data, pollution index data, conductivity data, pH value data, hardness data, dissolved oxygen concentration data, and temperature data. All online sensors are connected to the data acquisition module located in the control room of the water treatment system via signal transmission lines. The data acquisition module digitizes the real-time collected water quality parameters and transmits them to the centralized control system through a communication interface.

[0019] The centralized control system receives and stores water quality parameter data in real time, and establishes a water quality parameter monitoring database within the centralized control system. Based on the water quality parameter monitoring database, the centralized control system performs dynamic calculations and comparative analyses of water quality parameters to determine the short-term fluctuation trend and long-term change trend of tap water quality.

[0020] By deploying a complete online sensor array throughout the entire operation of the reverse osmosis system, and combining it with the real-time coordinated operation of the data acquisition module and the centralized control system, the operating parameters of the reverse osmosis system can be made controllable.

[0021] As a preferred embodiment of the present invention, step S200 specifically includes:

[0022] Step S200.1: Configure the influent flow rate regulating device and perform initial settings, configure the online sensor position and perform data acquisition, and set the judgment rules for turbidity, differential pressure and transmembrane pressure difference.

[0023] Step S200.2: Configure the flocculant dosing device and dosing control logic, configure the backwashing and dosing linkage control state machine, and perform data smoothing, trend analysis and adaptive threshold adjustment.

[0024] As a preferred embodiment of the present invention, step S300 specifically includes:

[0025] Step S300.1: Configure stable operation control of primary reverse osmosis and configure concentrate reflux ratio adjustment.

[0026] Step S300.2: Configure high-pressure pump frequency optimization.

[0027] The centralized control system automatically optimizes the operating frequency of the high-pressure pump inverter based on the high-pressure pump outlet pressure data measured by the pressure sensor installed at the outlet of the high-pressure pump of the first-stage reverse osmosis unit, combined with the calculation results of the system desalination rate. The high-pressure pump frequency adjustment range is set to 70%–100% of the rated frequency. When the system desalination rate drops by more than 3%, the high-pressure pump frequency is gradually increased in 2% increments until the system desalination rate recovers to the target value of 98% or more, or the high-pressure pump frequency reaches the upper limit of the rated frequency of 100%.

[0028] The centralized control system triggers low-dose acid and alkali flushing and scale inhibitor addition at regular intervals according to the operating cycle. The acid and alkali flushing cycle is initially set to once every 72 hours, the pH adjustment range of the flushing solution is 4.0–10.0, and the flushing time is set to 10 minutes. The scale inhibitor addition device uses a metering pump to add the scale inhibitor at a constant rate according to the flow rate. The initial addition concentration is set to 3 mg / L. When the average conductivity of the influent water of the first-stage reverse osmosis unit increases by more than 15% over 24 consecutive hours, the centralized control system increases the scale inhibitor addition concentration to 4 mg / L and generates an operating status prompt simultaneously.

[0029] As a preferred embodiment of the present invention, step S400 specifically includes:

[0030] Step S400.1: Configure the secondary reverse osmosis operation regulation and conductivity closed-loop control.

[0031] Step S400.2: Configure the product water homogenization device and dynamic reflux pipeline, and set the product water homogenization and system dynamic balance control.

[0032] To mitigate the impact of short-term fluctuations in permeate water from the secondary reverse osmosis unit on overall water quality stability at different times, a mechanical agitator and a recirculation pipeline are installed in the permeate tank of the secondary reverse osmosis unit. The agitator speed is set within the range of 30–60 rpm, with an initial setting of 45 rpm, to maintain thorough mixing of the water in the permeate tank. The recirculation pipeline consists of a recirculation pump, a regulating valve, and a flow meter. The recirculation ratio is set within the range of 8%–12%, with an initial setting of 10%. The recirculation ratio is automatically adjusted by the centralized control system based on real-time conductivity data and historical operating trends.

[0033] The centralized control system is equipped with conductivity sensors and flow meters at the outlet of the permeate tank to acquire real-time conductivity and instantaneous flow data of the homogenized permeate. When the conductivity of the homogenized permeate fluctuates by more than ±5 μS / cm, the centralized control system automatically increases the reflux ratio by 1% each time until the conductivity fluctuation range of the permeate returns to within ±5 μS / cm. If the conductivity fluctuation of the homogenized permeate exceeds ±5 μS / cm for 24 consecutive hours, an operation and maintenance inspection prompt is automatically generated, prompting manual inspection of the membrane element operation status and stirring device operation status of the secondary reverse osmosis unit.

[0034] The centralized control system achieves dynamic water quality balance by setting up a homogenized buffer zone between the product water tank of the secondary reverse osmosis unit and the high-purity demineralized water pipeline network in the plant area. The centralized control system uses the moving average method to perform dynamic smoothing calculations based on the short-term fluctuation trend of the product water conductivity.

[0035] When the moving average value exceeds the target value of 10 μS / cm for the conductivity of the product water for three consecutive calculation cycles, the centralized control system automatically triggers the scale inhibitor concentration adjustment and acid-base flushing advance program.

[0036] As a preferred embodiment of the present invention, step S500 specifically includes:

[0037] Step S500.1: Set the operating configuration of the hybrid ion exchanger and perform the hybrid ion exchanger operating status determination.

[0038] Step S500.2: Set the trigger for the regeneration program of the mixed ion exchanger, configure parallel switching to ensure continuous water supply, and configure the life management and regeneration cycle optimization of the mixed ion exchanger.

[0039] When the regeneration program is triggered by the centralized control system, the inlet and outlet switching valves of the mixed ion exchanger are first closed, and dilute acid and dilute alkali solutions are connected through the preset regeneration pipeline to achieve sequential regeneration. The regeneration steps include: acid washing stage, in which dilute hydrochloric acid solution at a concentration of 4%–5% is passed through the cation resin layer of the mixed ion exchanger and the acid washing time is set to 30 minutes; alkali washing stage, in which dilute sodium hydroxide solution at a concentration of 4%–5% is passed through the anion resin layer of the mixed ion exchanger and the alkali washing time is set to 30 minutes; and displacement rinsing stage, in which demineralized water is used for forward rinsing, the rinsing flow rate is set to 1.5 times the normal operating flow rate and the rinsing time is set to 20 minutes, until the conductivity of the effluent recovers to ≤0.20μS / cm.

[0040] The centralized control system monitors the changes in regenerated fluid flow and conductivity in real time throughout the entire regeneration process and generates a regeneration process operation report.

[0041] When the primary mixed ion exchanger enters the regeneration process, the centralized control system automatically switches to the standby mixed ion exchanger for operation. The switching valve of the standby mixed ion exchanger is automatically controlled by an electric actuator, and the switching time is set to ≤30 seconds. The standby mixed ion exchanger and the primary mixed ion exchanger adopt an equivalent resin layer structure and equivalent sensor configuration.

[0042] Based on historical monitoring data of conductivity difference and resin layer pressure drop, the centralized control system uses the moving average method to perform trend analysis on the regeneration cycle. The moving average calculation is the same as the dynamic smoothing calculation. When the moving average value increases by more than 15% compared with the previous average value within three consecutive calculation cycles, the centralized control system determines that the resin layer performance has deteriorated, automatically shortens the regeneration cycle by 10%–15%, and generates a prompt for maintenance personnel, suggesting that the resin be replaced.

[0043] The centralized control system monitors the conductivity data of the effluent from the hybrid ion exchanger in real time. The alarm threshold is set at 0.20 μS / cm. When the sampling value exceeds the alarm threshold for 5 consecutive times, the centralized control system automatically generates a serious water quality risk warning and starts the backup hybrid ion exchanger to switch over.

[0044] As a preferred embodiment of the present invention, step S600 specifically includes:

[0045] Step S600.1: Configure a unified acquisition mechanism for water quality and operating parameters throughout the entire process, configure a multivariate feedback control model, and set automatic optimization of reagent dosage and membrane flushing cycle.

[0046] In the operation of the reverse osmosis system in the power plant, key water quality parameters and operating parameters of the dual-media filter, ultrafiltration unit, first-stage reverse osmosis unit, second-stage reverse osmosis unit, and mixed ion exchanger are collected and integrated in a unified manner. The collected water quality parameters include: turbidity, pollution index, conductivity, pH value, dissolved oxygen concentration, and temperature. The collected operating parameters include: influent pressure, effluent pressure, transmembrane pressure difference, filter bed pressure difference, desalination rate, resin bed pressure drop, concentrate recirculation ratio, and high-pressure pump operating frequency. The raw data collected by the sensors are connected to the data acquisition module through signal transmission lines. The data acquisition module performs digital processing and transmits the data to the data fusion module of the centralized control system through the communication interface to form a complete database of full-process operating parameters.

[0047] The centralized control system establishes a multivariate feedback control model based on the integrated database. The model inputs are the conductivity, pH value, turbidity, SDI, desalination rate, filter layer pressure difference, transmembrane pressure difference, resin layer pressure drop and high-pressure pump frequency collected in real time by each unit. The outputs are optimization variables such as reagent dosage concentration, membrane flushing cycle and concentrate recirculation ratio. The feedback control model uses a weighted evaluation method to comprehensively score the stability of the product water quality.

[0048] The centralized control system automatically adjusts the flocculant dosage, scale inhibitor dosage, and acid-base flushing cycle based on the trend of the comprehensive score. When the comprehensive score is below 0.85 and the downward trend remains negative for three consecutive times, the flocculant dosage is corrected.

[0049] When the moving average conductivity of the secondary reverse osmosis unit exceeds 10 μS / cm for three consecutive cycles and the overall score decreases by more than 5%, the centralized control system triggers the acid-base flushing program in advance, shortening the flushing cycle by 20% and maintaining the flushing time at 10 minutes.

[0050] Step S600.2: Configure the concentrate recirculation and dynamic balance strategy, and establish a stable and controllable operating state with alarm feedback.

[0051] The centralized control system dynamically adjusts the concentrate recirculation ratio of the first-stage reverse osmosis unit based on the comprehensive score. The adjustment range of the concentrate recirculation ratio is set to 5%–15%, with an initial value of 10%. When the comprehensive score drops by more than 10% and the desalination rate of the first-stage reverse osmosis unit is lower than 98%, the concentrate recirculation ratio is increased by 1% each time until the desalination rate recovers or the concentrate recirculation ratio reaches 15%.

[0052] The centralized control system optimizes the reflux ratio of the product water tank of the secondary reverse osmosis unit in real time. The reflux ratio is set in the range of 8%–12%, with an initial value of 10%. When the conductivity of the mixed product water fluctuates by more than ±5μS / cm, the reflux ratio is increased by 0.5% each time until the fluctuation returns to within ±5μS / cm.

[0053] After feedback control is completed, the centralized control system performs a comprehensive verification of the water quality parameters of the entire process. When the comprehensive score is higher than 0.90 for 10 consecutive cycles, the system is considered to be operating stably. If the comprehensive score is lower than 0.70 or any key indicator exceeds the preset risk threshold, a water quality risk alarm is generated, and the operation and maintenance personnel are prompted to conduct manual inspection. The alarm information is presented in the form of trend curves and alarm lists on the centralized control system interface, and is also recorded in the operation log.

[0054] In summary, the control method for stabilizing and improving the quality of permeate from a power plant reverse osmosis system provided in this application dynamically adjusts the influent flow rate, backwash intensity, and flocculant concentration based on parameters such as turbidity, pollution index, conductivity, and pressure difference collected in real time by online sensors when the raw water quality experiences short-term fluctuations or the pollution load increases. Simultaneously, by continuously calculating the desalination rates of the first and second stage reverse osmosis units, the concentrate recirculation ratio and high-pressure pump frequency are automatically corrected to maintain the membrane module's operating state within the optimal range. The homogenization and dynamic recirculation devices configured in the second-stage reverse osmosis permeate tank can mitigate short-term fluctuations in permeate conductivity. Combined with the regeneration cycle optimization and parallel switching strategy of the mixed ion exchanger, stable control of effluent conductivity and resin bed pressure drop is achieved. This method effectively solves the problems of untimely response to water quality fluctuations, limited control methods, and lack of adaptive adjustment in the operating state of traditional reverse osmosis systems. It improves the precision and automation level of water quality control throughout the entire process, ensuring a long-term stable supply of high-purity demineralized water to the power plant. Attached Figure Description

[0055] Figure 1 This is an overall flowchart of a control method for stabilizing and improving the quality of permeate from a power plant reverse osmosis system, as provided in an embodiment of this application. Detailed Implementation

[0056] Please refer to Figure 1 The present invention illustrates a process flow of an embodiment of a control method for stabilizing and improving the quality of permeate from a reverse osmosis system in a power plant, according to the present disclosure.

[0057] like Figure 1 As shown, a method for regulating and improving the quality of permeate from a power plant reverse osmosis system includes the following steps:

[0058] Step S100: Configure the water treatment unit, obtain high-purity demineralized water, collect the operating parameters of the reverse osmosis system, and monitor them.

[0059] Step S200: Configure the influent flow rate regulating device and perform initial settings; configure the online sensor position and perform data acquisition; set the judgment rules for turbidity, differential pressure and transmembrane pressure difference; configure the flocculant dosing device and dosing control logic; configure the backwash and dosing linkage control state machine; and perform data smoothing, trend analysis and adaptive threshold adjustment.

[0060] Step S300: Configure stable operation control of primary reverse osmosis, configure concentrate reflux ratio adjustment, and configure high-pressure pump frequency optimization.

[0061] Step S400: Configure secondary reverse osmosis operation regulation and conductivity closed-loop control, configure product water homogenization device and dynamic reflux pipeline, and set product water homogenization and system dynamic balance control.

[0062] Step S500: Set the operating configuration of the mixed ion exchanger, perform mixed ion exchanger operating status determination, set the trigger for the mixed ion exchanger regeneration program, configure parallel switching to ensure continuous water supply, and configure mixed ion exchanger life management and regeneration cycle optimization.

[0063] Step S600: Configure a unified acquisition mechanism for water quality and operating parameters throughout the entire process, configure a multivariate feedback control model, set automatic optimization of reagent dosage and membrane flushing cycle, configure concentrate recirculation and dynamic balance strategies, and form a stable and controllable operating state and alarm feedback.

[0064] In some specific embodiments, step S100 specifically includes:

[0065] Step S100.1: Configure the water treatment unit, obtain high-purity demineralized water, collect the operating parameters of the reverse osmosis system, and monitor them.

[0066] In the power plant's water treatment system, tap water is first obtained through the city's water supply network. The obtained tap water enters a clear water tank located within the plant area. The clear water tank is used for preliminary storage and buffering of the incoming tap water. The tap water is then pressurized from the clear water tank by a chemical feed pump located at the outlet of the clear water tank. The pressurized tap water is then continuously transported to the subsequent water treatment units.

[0067] In the specific process of the water treatment unit, tap water sequentially enters a dual-media filter, an ultrafiltration unit, a first-stage reverse osmosis unit, a second-stage reverse osmosis unit, and a mixed ion exchanger. The dual-media filter is composed of quartz sand filter media and anthracite filter media, used to remove suspended solids and some colloidal impurities in the water. The ultrafiltration unit uses hollow fiber ultrafiltration membranes to intercept particles and bacteria. The first-stage reverse osmosis unit uses spiral wound membrane elements to initially remove dissolved salts. The second-stage reverse osmosis unit further desalinates the water produced by the first-stage reverse osmosis unit. The mixed ion exchanger is filled with a mixture of strong acidic cation exchange resin and strong basic anion exchange resin to remove residual ions and obtain high-purity desalinated water.

[0068] As tap water flows sequentially through a dual-media filter, an ultrafiltration device, a primary reverse osmosis device, a secondary reverse osmosis device, and a mixed ion exchanger, key water quality parameters are collected and monitored in real time.

[0069] Online sensors are installed at the inlet of the dual-media filter, at the outlet of the ultrafiltration unit, at the inlet and product water ends of the first-stage reverse osmosis unit, at the inlet and product water ends of the second-stage reverse osmosis unit, and at the outlet of the mixed ion exchanger.

[0070] Online sensors are used to collect turbidity data, pollution index data, conductivity data, pH value data, hardness data, dissolved oxygen concentration data, and temperature data. All online sensors are connected to the data acquisition module located in the control room of the water treatment system via signal transmission lines. The data acquisition module digitizes the real-time collected water quality parameters and transmits them to the centralized control system through a communication interface.

[0071] The centralized control system receives and stores water quality parameter data in real time, and establishes a water quality parameter monitoring database within the centralized control system. Based on the water quality parameter monitoring database, the centralized control system performs dynamic calculations and comparative analyses of water quality parameters to determine the short-term fluctuation trend and long-term change trend of tap water quality.

[0072] The alarm threshold for turbidity data is set to 1.0 NTU. When the turbidity data exceeds 1.0 NTU, the centralized control system generates an abnormal status prompt. The risk threshold for pollution index data is set to 5. When the pollution index data exceeds 5, the centralized control system records it as a serious pollution risk state. The conductivity threshold for the permeate end of the first-stage reverse osmosis unit is set to 50 μS / cm. When the conductivity data exceeds 50 μS / cm, the centralized control system judges it as a state of desalination performance degradation of the first-stage reverse osmosis unit.

[0073] By deploying a complete online sensor array throughout the entire operation of the reverse osmosis system, and combining it with the real-time coordinated operation of the data acquisition module and the centralized control system, the operating parameters of the reverse osmosis system can be made controllable.

[0074] In some specific embodiments, step S200 specifically includes:

[0075] Step S200.1: Configure the influent flow rate regulating device and perform initial settings, configure the online sensor position and perform data acquisition, and set the judgment rules for turbidity, differential pressure and transmembrane pressure difference.

[0076] The inlet flow rate regulating device refers to the regulating valve installed on the inlet pipeline of the dual-media filter and the variable frequency water pump linked to it. The inlet flow rate regulating device is used to control the instantaneous flow rate entering the dual-media filter according to a set flow curve. The specific configuration of the inlet flow rate regulating device includes: an adjustable speed water pump, an electric regulating valve, an electromagnetic flow meter for real-time measurement of the instantaneous flow rate, and a control valve position feedback sensor for closed-loop valve position control. The initial setting is: when the effective filter area of ​​the dual-media filter is A (m²),... 2 When the apparent influent velocity is initially set to 8–12 m / s, the initial flow rate is determined. 3 / (m 2 •h), the frequency converter of the water pump automatically adjusts according to the flow demand within the frequency range of 20%–100%.

[0077] The configuration locations of the online turbidity sensor, differential pressure transmitter, transmembrane differential pressure sensor, conductivity sensor, pH sensor, and temperature sensor are as follows: a conductivity sensor and a turbidity sensor are installed on the inlet pipe of the dual-media filter to obtain the feed water quality; a turbidity sensor and an inlet-outlet differential pressure measurement point are installed on the outlet pipe of the dual-media filter to obtain the outlet turbidity and filter bed pressure difference of the dual-media filter; a transmembrane differential pressure sensor and a product water turbidity sensor are respectively installed on the feed water side and the product water side of the ultrafiltration unit to obtain the operating conditions of the ultrafiltration membrane; and a conductivity sensor is installed at the feed water end of the first-stage reverse osmosis unit as the feed water conductivity detection point entering the first-stage reverse osmosis unit.

[0078] The fouling status of the filter bed and ultrafiltration membrane is quantified using physical quantities for calculation and judgment. The filter bed pressure difference is defined as the difference between the inlet water pressure and the outlet pressure, specifically:

[0079] ΔP LC =P jk -P ck

[0080] Where: ΔP LC This is the pressure difference of the filter bed in a dual-media filter, measured in megapascals (MPa). This pressure difference is used to determine filter bed fouling and backwash triggering. jk This is the instantaneous static pressure measured by a pressure sensor installed at the inlet pipe of the dual-media filter, in megapascals (MPa). The pressure sensor should be installed close to the filter inlet flange and connected to the data acquisition module. ck This is the instantaneous static pressure measured by a pressure sensor installed at the outlet pipe of the dual-media filter, in megapascals (MPa). The pressure sensor should be installed close to the filter outlet flange and connected to the data acquisition module.

[0081] The transmembrane pressure difference in ultrafiltration is defined as the difference between the pressure on the feed water side and the pressure on the product water side of the ultrafiltration membrane, specifically:

[0082] TMP = P jsc -Pcsc

[0083] In the formula: TMP represents the transmembrane pressure difference of the ultrafiltration device, with the unit being megapascals. The transmembrane pressure difference is used to determine the degree of ultrafiltration membrane fouling and the conditions for triggering cleaning. P jsc This is the instantaneous static pressure measured by a pressure sensor installed on the inlet side of the ultrafiltration unit, in megapascals (MPa). This sensor should be placed close to the ultrafiltration inlet manifold. csc It is the instantaneous static pressure measured by a pressure sensor installed on the permeate side of the ultrafiltration unit, in megapascals. This sensor should be placed close to the ultrafiltration permeate manifold.

[0084] When the filter bed pressure difference is ≥0.08MPa, the dual-media filter is determined to need backwashing. When the outlet turbidity of the dual-media filter is ≥1.0NTU, it is determined that there is an abnormal surge in turbidity in the filter bed. The control system starts the enhanced backwashing program and records it as a serious turbidity risk event. When TMP is ≥0.10MPa, it is determined that the ultrafiltration membrane needs to be cleaned or backwashed. The control system triggers the ultrafiltration backwashing program.

[0085] The backwashing procedure is completed by the control valve and the backwash pump. The backwashing duration is initially set to 5 minutes, and the backwash water flow rate is set to 1.2–1.5 times the normal operating inlet water flow rate. After the backwashing is completed, a 2-minute forward flush is performed to restore operation. If the cumulative number of enhanced backwashing times is ≥3 times in the same day, it is recorded as a short-term high pollution load and triggers a manual inspection command from the operation and maintenance department.

[0086] Step S200.2: Configure the flocculant dosing device and dosing control logic, configure the backwashing and dosing linkage control state machine, and perform data smoothing, trend analysis and adaptive threshold adjustment.

[0087] The flocculant dosing device refers to a complete flocculant preparation and metering system, including: a flocculant dissolving tank, a mechanical stirrer, a metering pump, a dosing point, and a flow meter. Polychlorohydrin or cationic polyacrylamide is preferred as the flocculant. The specific formulation and effective dosing range are determined through small-scale tests before dosing. The flocculant dosing point is located in the inlet pipe section of the ultrafiltration unit. After dosing, the flocculant undergoes thorough flocculation and mixing in the mixer before entering the ultrafiltration unit. The dosing triggering rules and dosing control logic are as follows: when the pollution index (SDI) of the ultrafiltration unit inlet water is ≥4.0 and SDI <5.0, automatic low-dose dosing is initiated; when SDI ≥5.0, automatic high-dose dosing is initiated and a severe pollution alarm is generated. The dosing concentration calculation adopts a proportional correction principle. The specific calculation for the dosing concentration C is as follows:

[0088] C = C0 + k × (SDI - SDI) ref )

[0089] In the formula: C is the target dosage concentration of flocculant or chemical, in milligrams per liter (mg / L). This concentration is the target dosage concentration set by the metering pump and is used to calculate the dosing rate based on the flow rate. C0 is the baseline dosage concentration, in milligrams per liter. The baseline value is determined through field trials or historical operating experience; an initial value of 0.5 mg / L is recommended in the example. k is the correction coefficient for the dosage concentration, in milligrams per liter. The correction coefficient is determined through field fitting; an initial value of 0.2 mg / L is recommended in the example. SDI is the influent pollution index (Silt Density Index), a dimensionless indicator. The pollution index is obtained by sampling according to industry standards and measured using prescribed methods. It is input into the control system as the result of on-site online or periodic offline monitoring. ref It is a reference pollution index, with dimensionless units. The reference value is used to calibrate the baseline. The example recommends an initial value of 3.0.

[0090] The dosing control is implemented as a closed-loop control. The metering pump calculates the dosing acceleration rate R based on the calculated C and the real-time flow rate Q. The metering pump output is automatically adjusted according to R. The metering pump output is corrected by feedback from the dosing flow meter in a closed loop. The control system establishes a linkage state machine between the dual-media filter and the ultrafiltration device. The state machine includes four states: normal operation, alert operation, enhanced operation, and maintenance. The state transition rule is as follows: when the exponential smoothing value of any inlet or outlet sensor index rises for six consecutive times and exceeds the preset warning value, it enters alert operation. In alert operation, the backwashing frequency is automatically increased and low-dose flocculant dosing is initiated. When ΔP LC When the pressure is ≥0.08MPa, TMP≥0.10MPa, or SDI≥5.0, the system enters enhanced operation. Enhanced operation starts by extending the backwash time, increasing the backwash flow rate, and raising the flocculant concentration to the upper limit or the recommended value for on-site testing. If the cumulative number of enhanced operation times is ≥3 times within 24 hours, the control system will automatically generate an operation and maintenance work order to prompt manual inspection of the filter layer, membrane module, and dosing system.

[0091] The turbidity and SDI data collected online were subjected to trend smoothing. The trend was estimated using the exponential smoothing method. The smoothing value was calculated as follows:

[0092] S t =α×X t +(1-α)×S t-1

[0093] In the formula: S t X is the smoothed value (exponential smoothing value) at time t, used to describe the smoothing trend of sensor data. Its unit is the same as the original measurement value. α is the exponential smoothing coefficient, dimensionless, with a value range of 0 < α ≤ 1, and an initial value of 0.20. t It is the original sampled value at time t, obtained by measuring the online sensor and digitizing it through the data acquisition module, with units in seconds. t Same, St-1 It is the smoothed value of the previous sampling period, and the initial value S0 can be the first sampled value X0.

[0094] Based on historical operating data, the centralized control system can adaptively adjust the threshold. The adaptive adjustment strategy is as follows: if the daily average turbidity increases by more than 20% compared with the same period of previous years within a certain period of 30 consecutive days, the warning turbidity threshold at the inlet and outlet of the dual-media filter will be increased by 10% after confirmation by operation and maintenance personnel, and the backwashing strategy will be updated simultaneously. The adaptive adjustment must retain the manual confirmation process. The automatic adjustment result will generate suggestions on the control system interface and take effect after confirmation by operation and maintenance personnel.

[0095] In some specific embodiments, step S300 specifically includes:

[0096] Step S300.1: Configure stable operation control of primary reverse osmosis and configure concentrate reflux ratio adjustment.

[0097] In a primary reverse osmosis unit, based on the conductivity data of the feed water and the product water collected by conductivity sensors installed at the feed water and product water ends of the primary reverse osmosis unit, the centralized control system calculates the system desalination rate of the primary reverse osmosis unit in real time. The calculation of the system desalination rate is as follows:

[0098]

[0099] In the formula: R is the system desalination rate, expressed as a percentage, used to characterize the ability of a first-stage reverse osmosis unit to remove dissolved salts; C p This is the conductivity at the product water end, measured in microsiemens per centimeter (µSiemens per centimeter), and is measured in real time by a conductivity sensor installed at the product water end of the first-stage reverse osmosis unit. (C) f It is the conductivity at the inlet end, measured in micro-Siemens per centimeter, and is measured in real time by a conductivity sensor installed at the inlet end of the first-stage reverse osmosis unit.

[0100] Within the centralized control system, the target value for the system desalination rate is set to 98%. When the system desalination rate is calculated to be lower than the target value of 98% for five consecutive times and the decrease exceeds 3%, the centralized control system automatically triggers the first-level reverse osmosis operation stabilization control program.

[0101] The stable operation control procedure for primary reverse osmosis includes adjusting the concentrate reflux ratio, optimizing the high-pressure pump frequency, and performing acid and alkali flushing and scale inhibitor addition during the operating cycle.

[0102] The centralized control system calculates the instantaneous flow rate of the concentrate from the first-stage reverse osmosis unit based on the instantaneous flow rates of the influent and permeate collected by the real-time flow meter. It then adjusts the concentrate recirculation ratio through the concentrate recirculation regulating valve. The adjustment range of the concentrate recirculation ratio is set to 5%–15%, with an initial setting of 10%. When the system desalination rate drops by more than 3%, the concentrate recirculation ratio is gradually increased by 2% each time until the system desalination rate recovers to the target value of 98% or more, or the concentrate recirculation ratio reaches the upper limit of 15%.

[0103] Step S300.2: Configure high-pressure pump frequency optimization.

[0104] The centralized control system automatically optimizes the operating frequency of the high-pressure pump inverter based on the high-pressure pump outlet pressure data measured by the pressure sensor installed at the outlet of the high-pressure pump of the first-stage reverse osmosis unit, combined with the calculation results of the system desalination rate. The high-pressure pump frequency adjustment range is set to 70%–100% of the rated frequency. When the system desalination rate drops by more than 3%, the high-pressure pump frequency is gradually increased in 2% increments until the system desalination rate recovers to the target value of 98% or more, or the high-pressure pump frequency reaches the upper limit of the rated frequency of 100%.

[0105] The centralized control system triggers low-dose acid and alkali flushing and scale inhibitor addition at regular intervals according to the operating cycle. The acid and alkali flushing cycle is initially set to once every 72 hours, the pH adjustment range of the flushing solution is 4.0–10.0, and the flushing time is set to 10 minutes. The scale inhibitor addition device uses a metering pump to add the scale inhibitor at a constant rate according to the flow rate. The initial addition concentration is set to 3 mg / L. When the average conductivity of the influent water of the first-stage reverse osmosis unit increases by more than 15% over 24 consecutive hours, the centralized control system increases the scale inhibitor addition concentration to 4 mg / L and generates an operating status prompt simultaneously.

[0106] In some specific embodiments, step S400 specifically includes:

[0107] Step S400.1: Configure the secondary reverse osmosis operation regulation and conductivity closed-loop control.

[0108] During the operation of the secondary reverse osmosis unit, the permeate from the primary reverse osmosis unit serves as the feed water for the secondary reverse osmosis unit. After being pressurized by the secondary high-pressure pump, it enters the secondary reverse osmosis membrane element group. The centralized control system calculates the desalination rate of the secondary reverse osmosis unit in real time based on the data collected by the conductivity sensors at the feed and permeate ends of the secondary reverse osmosis unit, and performs closed-loop control of the permeate conductivity. The system desalination rate of the secondary reverse osmosis unit is calculated as follows:

[0109]

[0110] In the formula: R2 is the system desalination rate of the second-stage reverse osmosis unit, expressed as a percentage, used to characterize the ability of the second-stage reverse osmosis unit to remove dissolved salts; C p2 This refers to the conductivity of the permeate end of the secondary reverse osmosis unit, measured in microsiemens per centimeter (µSiemens per centimeter). It is measured in real-time by a conductivity sensor installed at the permeate end. (C) f2 It is the conductivity of the inlet water of the secondary reverse osmosis unit, measured in micro-Siemens per centimeter, and is measured in real time by a conductivity sensor installed at the inlet water.

[0111] In the centralized control system, the target value for the permeate conductivity of the secondary reverse osmosis unit is set to ≤10μS / cm, and the fluctuation control threshold for the permeate conductivity is set to ±5μS / cm. When the permeate conductivity exceeds the target value or the fluctuation range exceeds ±5μS / cm for 5 consecutive samplings, the centralized control system automatically triggers the secondary high-pressure pump frequency optimization program. The adjustment range of the secondary high-pressure pump frequency is set to 75%–100% of the rated frequency, with an adjustment step value of 1.5%, until the permeate conductivity returns to the set target value range.

[0112] Step S400.2: Configure the product water homogenization device and dynamic reflux pipeline, and set the product water homogenization and system dynamic balance control.

[0113] To mitigate the impact of short-term fluctuations in permeate water from the secondary reverse osmosis unit on overall water quality stability at different times, a mechanical agitator and a recirculation pipeline are installed in the permeate tank of the secondary reverse osmosis unit. The agitator speed is set within the range of 30–60 rpm, with an initial setting of 45 rpm, to maintain thorough mixing of the water in the permeate tank. The recirculation pipeline consists of a recirculation pump, a regulating valve, and a flow meter. The recirculation ratio is set within the range of 8%–12%, with an initial setting of 10%. The recirculation ratio is automatically adjusted by the centralized control system based on real-time conductivity data and historical operating trends.

[0114] The centralized control system is equipped with conductivity sensors and flow meters at the outlet of the permeate tank to acquire real-time conductivity and instantaneous flow data of the homogenized permeate. When the conductivity of the homogenized permeate fluctuates by more than ±5 μS / cm, the centralized control system automatically increases the reflux ratio by 1% each time until the conductivity fluctuation range of the permeate returns to within ±5 μS / cm. If the conductivity fluctuation of the homogenized permeate exceeds ±5 μS / cm for 24 consecutive hours, an operation and maintenance inspection prompt is automatically generated, prompting manual inspection of the membrane element operation status and stirring device operation status of the secondary reverse osmosis unit.

[0115] The centralized control system achieves dynamic water quality balance by setting up a homogenization buffer zone between the product water tank of the secondary reverse osmosis unit and the high-purity demineralized water pipeline network in the plant area. Based on the short-term fluctuation trend of the product water conductivity, the centralized control system uses a moving average method for dynamic smoothing calculation, specifically:

[0116]

[0117] Where: M t X is the moving average value at time t, measured in microsiemens per centimeter (μS / cm), used to smooth short-term fluctuations in the conductivity of the produced water. n is the time window length of the moving average, ranging from 5 to 10, initially set to 6. t-i It is the real-time sampled value at time ti, which is measured by the conductivity sensor at the product water end.

[0118] When the moving average value exceeds the target value of 10 μS / cm for the conductivity of the product water for three consecutive calculation cycles, the centralized control system automatically triggers the scale inhibitor concentration adjustment and acid-base flushing advance program.

[0119] In some specific embodiments, step S500 specifically includes:

[0120] Step S500.1: Set the operating configuration of the hybrid ion exchanger and perform the hybrid ion exchanger operating status determination.

[0121] During the process of permeate from the secondary reverse osmosis unit entering the mixed ion exchanger, a mixed bed structure of strongly acidic cation exchange resin and strongly basic anion exchange resin is configured. Conductivity and pressure sensors are installed at the inlet end of the mixed ion exchanger to collect influent conductivity and pressure data in real time. Conductivity and pressure sensors are installed at the outlet end of the mixed ion exchanger to collect effluent conductivity and pressure data in real time. All data collected by the sensors are connected to the data acquisition module through signal transmission lines and uploaded by the data acquisition module to the centralized control system to achieve full monitoring of the operating status.

[0122] The centralized control system calculates the conductivity difference in real time based on the influent and effluent conductivity data. The calculation of the conductivity difference is as follows:

[0123] ΔC=C in -C out

[0124] In the formula: ΔC is the difference in conductivity between the inlet and outlet of the mixed ion exchanger, in microsiemens per centimeter. in This refers to the conductivity at the inlet of the mixed ion exchanger, measured in microsiemens per centimeter (µS / cm), or C. outIt is the conductivity at the outlet of the mixed ion exchanger, measured in microsiemens per centimeter.

[0125] The centralized control system calculates the resin layer pressure drop in real time based on inlet and outlet water pressure data. The calculation of the resin layer pressure drop is as follows:

[0126] ΔP resin =P in -P out

[0127] Where: ΔP resin This is the pressure drop across the resin layer of a mixed ion exchanger, measured in megapascals (P). in This is the pressure at the inlet of the mixed ion exchanger, measured in megapascals (P). out It is the pressure at the outlet of the mixed ion exchanger, measured in megapascals (MPA).

[0128] When the effluent conductivity exceeds 0.20 μS / cm or the resin bed pressure drop exceeds 0.05 MPa, the centralized control system determines that the mixed ion exchanger has entered a critical failure state and triggers the regeneration program.

[0129] Step S500.2: Set the trigger for the regeneration program of the mixed ion exchanger, configure parallel switching to ensure continuous water supply, and configure the life management and regeneration cycle optimization of the mixed ion exchanger.

[0130] When the regeneration program is triggered by the centralized control system, the inlet and outlet switching valves of the mixed ion exchanger are first closed, and dilute acid and dilute alkali solutions are connected through the preset regeneration pipeline to achieve sequential regeneration. The regeneration steps include: acid washing stage, in which dilute hydrochloric acid solution at a concentration of 4%–5% is passed through the cation resin layer of the mixed ion exchanger and the acid washing time is set to 30 minutes; alkali washing stage, in which dilute sodium hydroxide solution at a concentration of 4%–5% is passed through the anion resin layer of the mixed ion exchanger and the alkali washing time is set to 30 minutes; and displacement rinsing stage, in which demineralized water is used for forward rinsing, the rinsing flow rate is set to 1.5 times the normal operating flow rate and the rinsing time is set to 20 minutes, until the conductivity of the effluent recovers to ≤0.20μS / cm.

[0131] The centralized control system monitors the changes in regenerated fluid flow and conductivity in real time throughout the entire regeneration process and generates a regeneration process operation report.

[0132] When the primary mixed ion exchanger enters the regeneration process, the centralized control system automatically switches to the standby mixed ion exchanger for operation. The switching valve of the standby mixed ion exchanger is automatically controlled by an electric actuator, and the switching time is set to ≤30 seconds. The standby mixed ion exchanger and the primary mixed ion exchanger adopt an equivalent resin layer structure and equivalent sensor configuration.

[0133] Based on historical monitoring data of conductivity difference and resin layer pressure drop, the centralized control system uses the moving average method to perform trend analysis on the regeneration cycle. The moving average calculation is the same as the dynamic smoothing calculation. When the moving average value increases by more than 15% compared with the previous average value within three consecutive calculation cycles, the centralized control system determines that the resin layer performance has deteriorated, automatically shortens the regeneration cycle by 10%–15%, and generates a prompt for maintenance personnel, suggesting that the resin be replaced.

[0134] The centralized control system monitors the conductivity data of the effluent from the hybrid ion exchanger in real time. The alarm threshold is set at 0.20 μS / cm. When the sampling value exceeds the alarm threshold for 5 consecutive times, the centralized control system automatically generates a serious water quality risk warning and starts the backup hybrid ion exchanger to switch over.

[0135] In some specific embodiments, step S600 specifically includes:

[0136] Step S600.1: Configure a unified acquisition mechanism for water quality and operating parameters throughout the entire process, configure a multivariate feedback control model, and set automatic optimization of reagent dosage and membrane flushing cycle.

[0137] In the operation of the reverse osmosis system in the power plant, key water quality parameters and operating parameters of the dual-media filter, ultrafiltration unit, first-stage reverse osmosis unit, second-stage reverse osmosis unit, and mixed ion exchanger are collected and integrated in a unified manner. The collected water quality parameters include: turbidity, pollution index, conductivity, pH value, dissolved oxygen concentration, and temperature. The collected operating parameters include: influent pressure, effluent pressure, transmembrane pressure difference, filter bed pressure difference, desalination rate, resin bed pressure drop, concentrate recirculation ratio, and high-pressure pump operating frequency. The raw data collected by the sensors are connected to the data acquisition module through signal transmission lines. The data acquisition module performs digital processing and transmits the data to the data fusion module of the centralized control system through the communication interface to form a complete database of full-process operating parameters.

[0138] The centralized control system establishes a multivariate feedback control model based on the integrated database. The model inputs are real-time data collected from each unit, including conductivity, pH, turbidity, SDI, desalination rate, filter bed pressure difference, transmembrane pressure difference, resin bed pressure drop, and high-pressure pump frequency. The outputs are optimized variables such as reagent dosage, membrane flushing cycle, and concentrate recirculation ratio. The feedback control model uses a weighted evaluation method to comprehensively score the stability of the permeate water quality. The comprehensive score is calculated as follows:

[0139] S score =w1·R RO1 +w2·R RO2 -w3·C out -w4·SDI-w5·ΔP resin

[0140] In the formula: Sscore This is a comprehensive score, measured in dimensionless units, used to characterize the water quality and stability throughout the entire process. R RO1 R represents the desalination rate of the first-stage reverse osmosis unit, expressed as a percentage. RO2 The desalination rate of the secondary reverse osmosis unit is expressed as a percentage (C). out The conductivity of the effluent from the mixed ion exchanger is expressed in μS / cm. SDI is the influent fouling index of the ultrafiltration unit, expressed as dimensionless. ΔP resin The pressure drop of the resin layer in the mixed ion exchanger is expressed in MPa. w1, w2, w3, w4, and w5 are weighting coefficients determined by fitting historical operating data, with recommended initial values ​​of 0.25, 0.25, 0.20, 0.15, and 0.15, respectively.

[0141] The centralized control system automatically adjusts the flocculant dosage, scale inhibitor dosage, and acid / alkali flushing cycle based on the trend of the comprehensive score. When the comprehensive score is below 0.85 and the downward trend remains negative for three consecutive times, the flocculant dosage is corrected, specifically as follows:

[0142] C adj =C base +β(0.85-S score )

[0143] In the formula: C adj This refers to the corrected flocculant concentration, expressed in mg / L, C. base The baseline concentration is expressed in mg / L, with a recommended initial value of 0.5 mg / L. β is the adjustment factor, expressed in mg / L, with a recommended initial value of 0.3 mg / L.

[0144] When the moving average conductivity of the secondary reverse osmosis unit exceeds 10 μS / cm for three consecutive cycles and the overall score decreases by more than 5%, the centralized control system triggers the acid-base flushing program in advance, shortening the flushing cycle by 20% and maintaining the flushing time at 10 minutes.

[0145] Step S600.2: Configure the concentrate recirculation and dynamic balance strategy, and establish a stable and controllable operating state with alarm feedback.

[0146] The centralized control system dynamically adjusts the concentrate recirculation ratio of the first-stage reverse osmosis unit based on the comprehensive score. The adjustment range of the concentrate recirculation ratio is set to 5%–15%, with an initial value of 10%. When the comprehensive score drops by more than 10% and the desalination rate of the first-stage reverse osmosis unit is lower than 98%, the concentrate recirculation ratio is increased by 1% each time until the desalination rate recovers or the concentrate recirculation ratio reaches 15%.

[0147] The centralized control system optimizes the reflux ratio of the product water tank of the secondary reverse osmosis unit in real time. The reflux ratio is set in the range of 8%–12%, with an initial value of 10%. When the conductivity of the mixed product water fluctuates by more than ±5μS / cm, the reflux ratio is increased by 0.5% each time until the fluctuation returns to within ±5μS / cm.

[0148] After feedback control is completed, the centralized control system performs a comprehensive verification of the water quality parameters of the entire process. When the comprehensive score is higher than 0.90 for 10 consecutive cycles, the system is considered to be operating stably. If the comprehensive score is lower than 0.70 or any key indicator exceeds the preset risk threshold, a water quality risk alarm is generated, and the operation and maintenance personnel are prompted to conduct manual inspection. The alarm information is presented in the form of trend curves and alarm lists on the centralized control system interface, and is also recorded in the operation log.

[0149] In practical application, the power plant's water treatment system firstly uses a clear water tank as a raw water buffer unit. After municipal tap water is transported into the clear water tank, it is pressurized by a chemical feedwater pump and sent to subsequent treatment stages. The water treatment unit sequentially includes a dual-media filter, an ultrafiltration unit, a primary reverse osmosis unit, a secondary reverse osmosis unit, and a mixed ion exchanger. The dual-media filter uses a combination of quartz sand and anthracite filter media, with an effective filter layer height of not less than 1.2m, used to remove suspended solids and colloidal impurities. The ultrafiltration unit is equipped with hollow fiber membrane modules to intercept bacteria and particles. The primary reverse osmosis unit... Both the primary and secondary reverse osmosis units use spiral wound membrane elements, which are used for the initial removal of dissolved salts and the deep desalination, respectively. The mixed ion exchanger is filled with strong acid cation exchange resin and strong base anion exchange resin to remove residual ions and ensure that the conductivity of the effluent is below 0.20 μS / cm. Online sensors are installed in key parts of each unit, including turbidity sensors, fouling index sensors, conductivity sensors, pH sensors, dissolved oxygen sensors, temperature sensors, and differential pressure sensors. These sensors are connected to the centralized control system through signal lines to ensure continuous monitoring of water quality parameters and operating status.

[0150] Next, an electric regulating valve and a variable frequency water pump are installed at the inlet of the dual-media filter to regulate the inlet water flow rate. The initial apparent flow velocity is set to 8–12 m / s. 3 / (m 2h), closed-loop control is achieved based on feedback from the online flow meter. The pressure sensors at the inlet and outlet of the dual-media filter measure the filter bed pressure difference in real time. The threshold is set to 0.08MPa. When the threshold is exceeded, the backwash program is automatically started. The outlet turbidity sensor detects the turbidity of the filtered water. When the outlet turbidity is ≥1.0NTU, it is determined that the filter bed turbidity is abnormal. The control system starts enhanced backwashing and records it as a risk event. Pressure sensors and turbidity sensors are installed on the inlet and product water sides of the ultrafiltration unit, respectively. The transmembrane pressure difference (TMP) is set to 0.10MPa as the trigger limit. When the limit is exceeded, the ultrafiltration backwash is started immediately. The backwash water flow rate is set to 1.2–1.5 times the normal operating inlet water flow rate and lasts for 5 minutes. After the backwash is completed, a 2-minute forward flush is performed to ensure that the deposits on the filter media and membrane surface are completely removed and stable operation is restored.

[0151] Subsequently, a flocculant injection point is set in the inlet pipe section of the ultrafiltration unit, and a stirrer is used to achieve thorough mixing, ensuring that colloids and particles in the raw water entering the membrane module are effectively coagulated. Polyaluminum chloride or cationic polyacrylamide is selected as the flocculant. The baseline dosage concentration was determined to be 0.5 mg / L through small-scale testing. Low-dose dosing is initiated when the SDI reaches 4.0, and high-dose dosing is initiated and a pollution alarm is triggered when the SDI reaches 5.0. The dosing system adopts closed-loop control, and the output of the dosing pump is automatically adjusted according to the real-time flow rate and the target dosage concentration to ensure that the flocculant plays its role within the effective range. The centralized control system constructs an operating state machine, including normal operation, alert operation, enhanced operation, and maintenance status. When the filter bed pressure difference reaches 0.08 MPa or the TMP reaches 0.10 MPa, the status automatically switches to enhanced operation, extending the backwash time and increasing the flocculant concentration. When the number of enhanced operations reaches 3 times within 24 hours, the system generates a manual inspection prompt.

[0152] Subsequently, conductivity sensors are installed at the inlet and outlet of the first-stage reverse osmosis unit to collect the conductivity of the influent and product water in real time. The centralized control system calculates the desalination rate of the system, with a target value set at 98%. When the calculated result is lower than 98% for five consecutive times and the decrease exceeds 3%, the control system adjusts the concentrate recirculation ratio. The initial ratio is set at 10%, with an allowable adjustment range of 5%–15%, increasing by 2% each time until the desalination rate recovers to the target value. The frequency adjustment range of the high-pressure pump inverter is 70%–100% of the rated frequency. When the desalination rate decreases by more than 3%, the frequency is increased step by step in 2% increments. During the operation cycle, a low-dose acid-base flush is automatically triggered every 72 hours. The pH adjustment range of the flushing solution is 4.0–10.0, the flushing time is 10 minutes, and the initial concentration of the scale inhibitor is set at 3 mg / L. When the 24-hour average conductivity of the influent increases by more than 15%, the concentration is increased to 4 mg / L to maintain the stable desalination performance of the membrane module.

[0153] Then, the primary reverse osmosis permeate is used as the secondary reverse osmosis feed water. After being pressurized by a high-pressure pump, it enters the membrane element group. Conductivity sensors are installed at both the secondary reverse osmosis feed water end and the permeate water end. The centralized control system calculates the desalination rate in real time and performs closed-loop control of the permeate water conductivity. The target value is set to ≤10μS / cm, with an allowable fluctuation range of ±5μS / cm. A mechanical stirrer is installed inside the permeate water tank, with a speed range of 30–60rpm and an initial value of 45rpm to ensure homogeneity of the permeate water. The return pipeline is equipped with a return pump, regulating valve, and flow meter. The return ratio is initially set to 10%, with an allowable adjustment range of 8%–12%. When the permeate water conductivity fluctuates beyond ±5μS / cm, the return ratio is increased by 1% each time until the water quality fluctuation returns to the set range. If the fluctuation exceeds the standard for 24 consecutive hours, the system generates an inspection prompt to check the operating status of the membrane module and stirrer.

[0154] Finally, conductivity sensors and pressure sensors are installed at the inlet and outlet of the mixed ion exchanger, respectively, to collect in-flow and out-of-flow conductivity and pressure data in real time. The system calculates the difference in in-flow and out-of-flow conductivity and the resin bed pressure drop. When the out-of-flow conductivity is ≥0.20μS / cm or the resin bed pressure drop is ≥0.05MPa, the regeneration program is started. The regeneration steps include an acid washing stage (4%–5% dilute hydrochloric acid concentration, 30 minutes), an alkaline washing stage (4%–5% dilute sodium hydroxide concentration, 30 minutes), and a displacement flushing stage (flushing flow rate is 1.5 times the normal operating flow rate, 20 minutes) to ensure the restoration of resin exchange capacity. The standby mixed ion exchanger is automatically switched via an electric valve with a switching time of ≤30 seconds to ensure continuous water supply. The centralized control system optimizes the regeneration cycle based on historical data. When the moving average value increases by more than 15% for three consecutive cycles, the regeneration cycle is shortened by 10%–15% to maintain the long-term stability of the overall product water quality of the system.

Claims

1. A method for regulating and improving the quality of permeate from a reverse osmosis system in a power plant, characterized in that, Includes the following steps: S100: Configure a water treatment unit, obtain high-purity demineralized water, collect and monitor the operating parameters of the reverse osmosis system; S200: Configure the influent flow rate regulating device and perform initial settings; configure the online sensor position and perform data acquisition; set the judgment rules for turbidity, differential pressure and transmembrane pressure difference; configure the flocculant dosing device and dosing control logic; configure the backwash and dosing linkage control state machine and perform data smoothing, trend analysis and adaptive threshold adjustment. S300 features: stable operation control of primary reverse osmosis, adjustment of concentrate reflux ratio, and optimization of high-pressure pump frequency. S400, equipped with two-stage reverse osmosis operation regulation and conductivity closed-loop control, equipped with product water homogenization device and dynamic reflux pipeline, and set product water homogenization and system dynamic balance control; S500: Set the operation configuration of the mixed ion exchanger, execute the operation status judgment of the mixed ion exchanger, set the trigger for the mixed ion exchanger regeneration program, configure parallel switching to ensure continuous water supply, and configure the life management and regeneration cycle optimization of the mixed ion exchanger. The S600 is equipped with a unified acquisition mechanism for water quality and operating parameters throughout the entire process, a multivariate feedback control model, and automatic optimization of reagent dosage and membrane flushing cycle. It also features a concentrate recirculation and dynamic balance strategy, forming a stable and controllable operating state with alarm feedback.

2. The method for regulating and improving the quality of permeate from a power plant reverse osmosis system according to claim 1, characterized in that, S100 specifically includes: S100.1 Configure the water treatment unit, obtain high-purity demineralized water, collect the operating parameters of the reverse osmosis system, and monitor them; In the power plant's water treatment system, tap water is first obtained through the city's water supply network. The obtained tap water enters a clear water tank located within the plant area. The clear water tank is used for preliminary storage and buffering of the incoming tap water. The tap water is pressurized from the clear water tank by a chemical feed pump located at the outlet of the clear water tank. The pressurized tap water is then continuously transported to the subsequent water treatment units. In the specific process of the water treatment unit, tap water sequentially enters a dual-media filter, an ultrafiltration unit, a first-stage reverse osmosis unit, a second-stage reverse osmosis unit, and a mixed ion exchanger. The dual-media filter is composed of quartz sand filter media and anthracite filter media, used to remove suspended solids and some colloidal impurities in the water. The ultrafiltration unit uses hollow fiber ultrafiltration membranes to intercept particles and bacteria. The first-stage reverse osmosis unit uses spiral wound membrane elements to initially remove dissolved salts. The second-stage reverse osmosis unit further desalinates the water produced by the first-stage reverse osmosis unit. The mixed ion exchanger is filled with a mixture of strong acid cation exchange resin and strong base anion exchange resin to remove residual ions and obtain high-purity desalinated water. As tap water flows sequentially through a dual-media filter, an ultrafiltration device, a primary reverse osmosis device, a secondary reverse osmosis device, and a mixed ion exchanger, key water quality parameters are collected and monitored in real time. Online sensors are installed at the inlet of the dual-media filter, at the outlet of the ultrafiltration unit, at the inlet and outlet of the first-stage reverse osmosis unit, at the inlet and outlet of the second-stage reverse osmosis unit, and at the outlet of the mixed ion exchanger. Online sensors are used to collect turbidity data, pollution index data, conductivity data, pH value data, hardness data, dissolved oxygen concentration data, and temperature data. All online sensors are connected to the data acquisition module located in the control room of the water treatment system via signal transmission lines. The data acquisition module digitizes the real-time collected water quality parameters and transmits them to the centralized control system via a communication interface. The centralized control system receives and stores water quality parameter data in real time, and establishes a water quality parameter monitoring database within the centralized control system. Based on the water quality parameter monitoring database, the centralized control system performs dynamic calculations and comparative analyses of water quality parameters to determine the short-term fluctuation trend and long-term change trend of tap water quality. By deploying a complete online sensor array throughout the entire operation of the reverse osmosis system, and combining it with the real-time coordinated operation of the data acquisition module and the centralized control system, the operating parameters of the reverse osmosis system can be made controllable.

3. The method for regulating and improving the quality of permeate from a power plant reverse osmosis system according to claim 1, characterized in that, S200 specifically includes: S200.1 Configure the influent flow rate regulating device and perform initial settings; configure the online sensor position and perform data acquisition; set the judgment rules for turbidity, differential pressure and transmembrane pressure difference. The inlet flow rate regulating device refers to the regulating valve installed on the inlet pipeline of the dual-media filter and the variable frequency water pump linked to it. The inlet flow rate regulating device is used to control the instantaneous flow rate entering the dual-media filter according to a set flow curve. The specific configuration of the inlet flow rate regulating device includes: an adjustable speed water pump, an electric regulating valve, an electromagnetic flow meter for real-time measurement of the instantaneous flow rate, and a control valve position feedback sensor for closed-loop valve position control. The initial setting is: when the effective filter area of ​​the dual-media filter is A (m²),... 2 When the apparent influent velocity is initially set to 8–12 m / s, the initial flow rate is determined. 3 / (m 2 •h), the frequency converter of the water pump automatically adjusts according to the flow demand within the frequency range of 20%–100%; The configuration locations of the online turbidity sensor, differential pressure transmitter, transmembrane differential pressure sensor, conductivity sensor, pH sensor, and temperature sensor are as follows: a conductivity sensor and a turbidity sensor are installed on the inlet pipe of the dual-media filter to obtain the influent water quality; a turbidity sensor and an inlet-outlet differential pressure measurement point are installed on the outlet pipe of the dual-media filter to obtain the outlet turbidity and filter bed pressure difference of the dual-media filter; a transmembrane differential pressure sensor and a product water turbidity sensor are respectively installed on the inlet and product water sides of the ultrafiltration unit to obtain the operating conditions of the ultrafiltration membrane; and a conductivity sensor is installed at the inlet end of the first-stage reverse osmosis unit as the influent conductivity detection point for the influent entering the first-stage reverse osmosis unit. The fouling status of the filter bed and ultrafiltration membrane is quantified by physical quantity calculation and judgment. The filter bed pressure difference is defined as the difference between the inlet water pressure and the outlet pressure. The transmembrane pressure difference in ultrafiltration is defined as the difference between the pressure on the feed water side and the pressure on the product water side of the ultrafiltration membrane. The backwashing process is completed by the control valve and the backwashing pump. The backwashing duration is initially set to 5 minutes, and the backwashing water flow rate is set to 1.2–1.5 times the normal operating inlet water flow rate. After the backwashing is completed, a 2-minute forward flush is performed to restore operation. If the cumulative number of enhanced backwashing times is ≥3 times in the same day, it will be recorded as a short-term high pollution load and trigger a manual inspection command from the operation and maintenance department. S200.2 Configure the flocculant dosing device and dosing control logic, configure the backwashing and dosing linkage control state machine, and perform data smoothing, trend analysis and adaptive threshold adjustment; The flocculant dosing device refers to a complete flocculant preparation and metering system, including: a flocculant dissolving tank, a mechanical stirrer, a metering pump, a dosing injection point, and a metering flow monitoring meter. Polychlorohydrin or cationic polyacrylamide is preferred as the flocculant. The specific formulation and effective dosing range are determined through small-scale tests before dosing. The flocculant dosing injection point is located in the inlet pipe section of the ultrafiltration unit. After dosing, the flocculant undergoes thorough flocculation and mixing in the mixer before entering the ultrafiltration unit. The dosing triggering rules and dosing control logic are as follows: when the pollution index (SDI) of the ultrafiltration unit inlet water is ≥4.0 and SDI <5.0, automatic low-dose dosing is initiated; when SDI ≥5.0, automatic high-dose dosing is initiated and a severe pollution alarm is generated. The dosing concentration calculation adopts a proportional correction principle, with a dosing concentration C. The dosing control is implemented as a closed-loop control. The metering pump calculates the dosing acceleration rate R based on the calculated C and the real-time flow rate Q. The metering pump output is automatically adjusted according to R. The metering pump output is corrected by feedback from the dosing flow meter in a closed loop. The control system establishes a linkage state machine between the dual-media filter and the ultrafiltration device. The state machine includes four states: normal operation, alert operation, enhanced operation, and maintenance. The state transition rule is as follows: when the exponential smoothing value of any inlet or outlet sensor index rises for six consecutive times and exceeds the preset warning value, it enters alert operation. In alert operation, the backwashing frequency is automatically increased and low-dose flocculant dosing is initiated. When ΔP LC When the pressure is ≥0.08MPa, TMP ≥0.10MPa, or SDI ≥5.0, the system enters enhanced operation. Enhanced operation involves extending the backwash time, increasing the backwash flow rate, and raising the flocculant concentration to the upper limit or the recommended value for on-site testing. If the cumulative number of enhanced operations is ≥3 times within 24 hours, the control system will automatically generate an operation and maintenance work order to prompt manual inspection of the filter layer, membrane module, and dosing system. The turbidity and SDI data collected online were subjected to trend smoothing, and the trend was estimated using the exponential smoothing method. Based on historical operating data, the centralized control system can adaptively adjust the threshold. The adaptive adjustment strategy is as follows: if the daily average turbidity increases by more than 20% compared with the same period of previous years within a certain period of 30 consecutive days, the warning turbidity threshold at the inlet and outlet of the dual-media filter will be increased by 10% after confirmation by operation and maintenance personnel, and the backwashing strategy will be updated simultaneously. The adaptive adjustment must retain the manual confirmation process. The automatic adjustment result will generate suggestions on the control system interface and take effect after confirmation by operation and maintenance personnel.

4. The method for regulating and improving the quality of permeate from a power plant reverse osmosis system according to claim 1, characterized in that, The S300 specifically includes: S300.1, equipped with first-stage reverse osmosis operation stability control, and equipped with concentrate reflux ratio adjustment; In the first-stage reverse osmosis unit, the centralized control system calculates the system desalination rate of the first-stage reverse osmosis unit in real time based on the conductivity data of the feed water and the product water collected by the conductivity sensors installed at the feed water end and the product water end of the first-stage reverse osmosis unit. Within the centralized control system, the target value for the system desalination rate is set to 98%. When the system desalination rate is calculated to be lower than the target value of 98% for five consecutive times and the decrease exceeds 3%, the centralized control system automatically triggers the first-level reverse osmosis operation stabilization control program. The stable operation control procedure for primary reverse osmosis includes adjusting the concentrate reflux ratio, optimizing the high-pressure pump frequency, and acid and alkali flushing and scale inhibitor addition during the operation cycle. The centralized control system calculates the instantaneous flow rate of the concentrate from the first-stage reverse osmosis unit based on the instantaneous flow rates of the influent and permeate collected by the real-time flow meter. It then adjusts the concentrate recirculation ratio through the concentrate recirculation regulating valve. The adjustment range of the concentrate recirculation ratio is set to 5%–15%, with an initial setting of 10%. When the system desalination rate drops by more than 3%, the concentrate recirculation ratio is gradually increased by 2% each time until the system desalination rate recovers to the target value of 98% or more, or the concentrate recirculation ratio reaches the upper limit of 15%. S300.2, Optimize the frequency of the high-pressure pump; The centralized control system automatically optimizes the operating frequency of the high-pressure pump inverter based on the high-pressure pump outlet pressure data measured by the pressure sensor installed at the outlet of the high-pressure pump of the first-stage reverse osmosis unit, combined with the calculation results of the system desalination rate. The high-pressure pump frequency adjustment range is set to 70%–100% of the rated frequency. When the system desalination rate drops by more than 3%, the high-pressure pump frequency is gradually increased in 2% increments until the system desalination rate recovers to the target value of 98% or more, or the high-pressure pump frequency reaches the upper limit of the rated frequency of 100%. The centralized control system triggers low-dose acid and alkali flushing and scale inhibitor addition at regular intervals according to the operating cycle. The acid and alkali flushing cycle is initially set to once every 72 hours, the pH adjustment range of the flushing solution is 4.0–10.0, and the flushing time is set to 10 minutes. The scale inhibitor addition device uses a metering pump to add the scale inhibitor at a constant rate according to the flow rate. The initial addition concentration is set to 3 mg / L. When the average conductivity of the influent water of the first-stage reverse osmosis unit increases by more than 15% over 24 consecutive hours, the centralized control system increases the scale inhibitor addition concentration to 4 mg / L and generates an operating status prompt simultaneously.

5. The method for regulating and improving the quality of permeate from a power plant reverse osmosis system according to claim 1, characterized in that, The S400 specifically includes: S400.1, configured with two-stage reverse osmosis operation regulation and conductivity closed-loop control; During the operation of the secondary reverse osmosis unit, the permeate from the primary reverse osmosis unit serves as the feed water for the secondary reverse osmosis unit. After being pressurized by the secondary high-pressure pump, it enters the secondary reverse osmosis membrane element group. The centralized control system calculates the desalination rate of the secondary reverse osmosis unit in real time based on the data collected by the conductivity sensors at the feed water end and the permeate water end of the secondary reverse osmosis unit, and performs closed-loop control on the permeate water conductivity. In the centralized control system, the target value for the permeate conductivity of the secondary reverse osmosis unit is set to ≤10μS / cm, and the fluctuation control threshold for the permeate conductivity is set to ±5μS / cm. When the permeate conductivity exceeds the target value or the fluctuation range exceeds ±5μS / cm for 5 consecutive samplings, the centralized control system automatically triggers the secondary high-pressure pump frequency optimization program. The adjustment range of the secondary high-pressure pump frequency is set to 75%–100% of the rated frequency, with an adjustment step value of 1.5%, until the permeate conductivity returns to the set target value range. S400.2 Configuring a product water homogenization device and a dynamic reflux pipeline, and setting product water homogenization and system dynamic balance control; To mitigate the impact of short-term fluctuations in permeate water from the secondary reverse osmosis unit at different times on the overall water quality stability, a mechanical agitator and a recirculation pipeline are installed in the permeate tank of the secondary reverse osmosis unit. The agitator speed is set within the range of 30–60 rpm, with an initial setting of 45 rpm, to maintain thorough mixing of the water in the permeate tank. The recirculation pipeline consists of a recirculation pump, a regulating valve, and a flow meter. The recirculation ratio is set within the range of 8%–12%, with an initial setting of 10%. The recirculation ratio is automatically adjusted by the centralized control system based on real-time conductivity data and historical operating trends. The centralized control system is equipped with conductivity sensors and flow meters at the outlet of the product water tank to acquire real-time conductivity and instantaneous flow data of the homogenized mixed product water. When the conductivity of the homogenized mixed product water fluctuates by more than ±5μS / cm, the centralized control system automatically increases the reflux ratio by 1% each time until the conductivity fluctuation range of the mixed product water returns to within ±5μS / cm. If the conductivity fluctuation of the homogenized mixed product water exceeds ±5μS / cm for 24 consecutive hours, an operation and maintenance inspection prompt is automatically generated, prompting manual inspection of the membrane element operation status and stirring device operation status of the secondary reverse osmosis unit. The centralized control system achieves dynamic water quality balance by setting up a homogeneous buffer zone between the product water tank of the secondary reverse osmosis unit and the high-purity demineralized water pipeline network in the plant area. The centralized control system uses the moving average method to perform dynamic smoothing calculation based on the short-term fluctuation trend of the product water conductivity. When the moving average value exceeds the target value of 10 μS / cm for the conductivity of the product water for three consecutive calculation cycles, the centralized control system automatically triggers the scale inhibitor concentration adjustment and acid-base flushing advance program.

6. The method for regulating and improving the quality of permeate from a power plant reverse osmosis system according to claim 1, characterized in that, The S500 specifically includes: S500.1 Set the operating configuration of the hybrid ion exchanger and perform hybrid ion exchanger operating status determination; During the process of permeate from the secondary reverse osmosis unit entering the mixed ion exchanger, a mixed bed structure of strongly acidic cation exchange resin and strongly basic anion exchange resin is configured. Conductivity and pressure sensors are installed at the inlet end of the mixed ion exchanger to collect influent conductivity and pressure data in real time. Conductivity and pressure sensors are installed at the outlet end of the mixed ion exchanger to collect effluent conductivity and pressure data in real time. All data collected by the sensors are connected to the data acquisition module through signal transmission lines and uploaded to the centralized control system by the data acquisition module to realize full monitoring of the operating status. The centralized control system calculates the conductivity difference in real time based on the influent conductivity data and the effluent conductivity data. The centralized control system calculates the resin layer pressure drop in real time based on inlet and outlet water pressure data. When the effluent conductivity exceeds 0.20 μS / cm or the resin bed pressure drop exceeds 0.05 MPa, the centralized control system determines that the mixed ion exchanger has entered a critical failure state and triggers the regeneration program. S500.2, Set the trigger for the regeneration program of the hybrid ion exchanger, configure parallel switching to ensure continuous water supply, and configure hybrid ion exchanger life management and regeneration cycle optimization; When the regeneration program is triggered by the centralized control system, the inlet and outlet switching valves of the mixed ion exchanger are first closed, and dilute acid and dilute alkali solutions are connected through the preset regeneration pipeline to achieve sequential regeneration. The regeneration steps include: acid washing stage, in which dilute hydrochloric acid solution at a concentration of 4%–5% is passed through the cation resin layer of the mixed ion exchanger and the acid washing time is set to 30 minutes; alkali washing stage, in which dilute sodium hydroxide solution at a concentration of 4%–5% is passed through the anion resin layer of the mixed ion exchanger and the alkali washing time is set to 30 minutes; and displacement rinsing stage, in which demineralized water is used for forward rinsing, the rinsing flow rate is set to 1.5 times the normal operating flow rate and the rinsing time is set to 20 minutes, until the conductivity of the effluent recovers to ≤0.20μS / cm. The centralized control system monitors the changes in regenerated fluid flow and conductivity in real time throughout the entire regeneration process and generates a regeneration process operation report. When the primary hybrid ion exchanger enters the regeneration process, the centralized control system automatically switches to the standby hybrid ion exchanger for operation. The switching valve of the standby hybrid ion exchanger is automatically controlled by an electric actuator. The switching time is set to ≤30 seconds. The standby hybrid ion exchanger and the primary hybrid ion exchanger adopt an equivalent resin layer structure and equivalent sensor configuration. Based on historical monitoring data of conductivity difference and resin layer pressure drop, the centralized control system uses the moving average method to perform trend analysis on the regeneration cycle. The moving average calculation is the same as the dynamic smoothing calculation. When the moving average value increases by more than 15% compared with the previous average value within three consecutive calculation cycles, the centralized control system determines that the resin layer performance has deteriorated, automatically shortens the regeneration cycle by 10%–15%, and generates a prompt for maintenance personnel, suggesting that the resin be replaced. The centralized control system monitors the conductivity data of the effluent from the hybrid ion exchanger in real time. The alarm threshold is set at 0.20 μS / cm. When the sampling value exceeds the alarm threshold for 5 consecutive times, the centralized control system automatically generates a serious water quality risk warning and starts the backup hybrid ion exchanger to switch over.

7. The method for regulating and improving the quality of permeate from a power plant reverse osmosis system according to claim 1, characterized in that, The S600 specifically includes: S600.1, Configure a unified acquisition mechanism for water quality and operating parameters throughout the entire process, configure a multivariate feedback control model, and set automatic optimization of reagent dosage and membrane flushing cycle; In the operation of the reverse osmosis system in the power plant, key water quality parameters and operating parameters of the dual-media filter, ultrafiltration unit, first-stage reverse osmosis unit, second-stage reverse osmosis unit, and mixed ion exchanger are collected and integrated in a unified manner. The collected water quality parameters include: turbidity, pollution index, conductivity, pH value, dissolved oxygen concentration, and temperature. The collected operating parameters include: influent pressure, effluent pressure, transmembrane pressure difference, filter bed pressure difference, desalination rate, resin bed pressure drop, concentrate recirculation ratio, and high-pressure pump operating frequency. The raw data collected by the sensors are connected to the data acquisition module through signal transmission lines. The data acquisition module performs digital processing and transmits the data to the data fusion module of the centralized control system through the communication interface to form a complete database of full-process operating parameters. The centralized control system establishes a multivariate feedback control model based on the integrated database. The model inputs are the conductivity, pH value, turbidity, SDI, desalination rate, filter layer pressure difference, transmembrane pressure difference, resin layer pressure drop and high-pressure pump frequency collected in real time by each unit. The outputs are optimization variables such as reagent dosage concentration, membrane flushing cycle and concentrate recirculation ratio. The feedback control model uses a weighted evaluation method to comprehensively score the stability of the product water quality. The centralized control system automatically adjusts the flocculant dosage, scale inhibitor dosage, and acid-base flushing cycle based on the trend of the comprehensive score. When the comprehensive score is below 0.85 and the downward trend remains negative for three consecutive times, the flocculant dosage is corrected. When the moving average conductivity of the secondary reverse osmosis unit exceeds 10 μS / cm for three consecutive cycles and the overall score decreases by more than 5%, the centralized control system will trigger the acid-base flushing program in advance, shortening the flushing cycle by 20% and keeping the flushing time at 10 minutes. S600.2 Configure concentrate recirculation and dynamic balancing strategies to form a stable and controllable operating state and alarm feedback; The centralized control system dynamically adjusts the concentrate recirculation ratio of the first-stage reverse osmosis unit based on the comprehensive score. The adjustment range of the concentrate recirculation ratio is set to 5%–15%, with an initial value of 10%. When the comprehensive score drops by more than 10% and the desalination rate of the first-stage reverse osmosis unit is lower than 98%, the concentrate recirculation ratio is increased by 1% each time until the desalination rate recovers or the concentrate recirculation ratio reaches 15%. The centralized control system optimizes the reflux ratio of the product water tank of the secondary reverse osmosis unit in real time. The reflux ratio is set in the range of 8%–12%, with an initial value of 10%. When the conductivity of the mixed product water fluctuates by more than ±5μS / cm, the reflux ratio is increased by 0.5% each time until the fluctuation returns to within ±5μS / cm. After feedback control is completed, the centralized control system performs a comprehensive verification of the water quality parameters of the entire process. When the comprehensive score is higher than 0.90 for 10 consecutive cycles, the system is considered to be operating stably. If the comprehensive score is lower than 0.70 or any key indicator exceeds the preset risk threshold, a water quality risk alarm is generated, and the operation and maintenance personnel are prompted to conduct manual inspection. The alarm information is presented in the form of trend curves and alarm lists on the centralized control system interface, and is also recorded in the operation log.

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