Reverse osmosis optimal dosing system and method based on ultraviolet sterilization

Abstract

The invention provides a reverse osmosis optimal dosing system and method based on ultraviolet sterilization, and the method comprises the following steps: firstly, the system monitors the influent microorganism load and water quality in real time, dynamically calculates the required ultraviolet dosage, and precisely adjusts the power of an ultraviolet sterilizer; secondly, according to the residual microorganism risk and the water inlet flow after ultraviolet treatment, the feeding amount of an oxidizing bactericide (such as sodium hypochlorite) is accurately adjusted according to a PID control strategy combining feedforward and feedback; meanwhile, according to the oxidation-reduction potential of the sterilized water body, a reducing agent (such as sodium hydrogen sulfite) is intelligently added to protect the reverse osmosis membrane. And finally, efficient cooperation of ultraviolet physical sterilization and chemical sterilization is achieved, on the premise that strict control over microbial pollution is guaranteed, the consumption and operation cost of chemical agents are remarkably reduced, generation of by-products is reduced, the service life of a reverse osmosis membrane is prolonged, and the intelligent level of system operation and the overall economic benefits are improved.

Description

Technical Field

[0001] This invention relates to the field of pharmaceutical dosing technology, and in particular to a reverse osmosis optimal dosing system and method based on ultraviolet sterilization. Background Technology

[0002] Reverse osmosis technology is widely used in seawater desalination, pure water production, and wastewater reuse due to its high desalination efficiency. However, reverse osmosis membranes are susceptible to microbial fouling, leading to decreased permeate flux, reduced desalination rate, increased operating pressure, increased energy consumption, and shortened membrane life. To control microbial fouling in reverse osmosis systems, bactericides (such as sodium hypochlorite and isothiazolinone) are typically added to the reverse osmosis feed water.

[0003] Traditional methods of administering medication mainly include: 1) Fixed dosage: A fixed dosage is set based on experience or rough water quality data. Disadvantages: It cannot adapt to fluctuations in raw water quality, which can easily lead to insufficient dosage (poor control effect) or excessive dosage (waste of chemicals, increased operating costs, possible generation of harmful byproducts, and increased burden on subsequent treatment).

[0004] 2) Flow-ratio dosing: The dosage is directly proportional to the influent flow rate. Disadvantage: It does not consider changes in water quality, and there is still a risk of insufficient or excessive dosage.

[0005] Ultraviolet (UV) sterilization effectively destroys the DNA / RNA of microorganisms, rendering them inactive. It is a physical sterilization method that does not produce byproducts and is environmentally friendly. Currently, UV sterilization devices and chemical dosing systems in reverse osmosis pretreatment typically operate independently, which presents the following problems: 1) Ultraviolet sterilization devices generally operate at a fixed power or are adjusted only according to the flow rate, failing to fully utilize their sterilization effect to optimize the addition of chemical agents.

[0006] 2) The chemical dosing system lacks real-time feedback on the microbial inactivation effect after ultraviolet sterilization treatment, making it impossible to accurately determine the required amount of chemical reagents to be added.

[0007] The lack of a mechanism for synergistic monitoring and interlocking control of the effects of ultraviolet sterilization and chemical treatment makes it difficult to achieve global optimization of the dosage of chemicals (i.e., minimizing chemical consumption while ensuring the safe and stable operation of the reverse osmosis system). Summary of the Invention

[0008] A first aspect of this disclosure provides a reverse osmosis optimal dosing system based on ultraviolet sterilization, comprising: The water inlet pipe is equipped with a flow meter 1 and an ultraviolet sterilizer 7 in sequence. A chemical dosing unit includes at least one dosing device for adding chemical agents to the inlet pipe; The sensing and detection unit includes a heterotrophic bacteria count detector 6 located upstream of the ultraviolet sterilizer 7 and an online residual chlorine meter 4 located on the water inlet pipe; The control system 11 is connected to the flow meter 1, the heterotrophic bacteria count detector 6, the online residual chlorine meter 4, the ultraviolet sterilizer 7, and the chemical dosing unit respectively. The control system 11 is configured as follows: The power of the ultraviolet sterilizer 7 is dynamically adjusted based on the initial heterotrophic bacteria count detected by the heterotrophic bacteria count detector 6 and the preset heterotrophic bacteria inactivation rate. The dosage of chemical reagents in the chemical dosing unit is dynamically adjusted based on the measured values ​​of the flow meter 1 and the online residual chlorine meter 4.

[0009] In conjunction with the first aspect, the chemical dosing unit includes an oxidizing bactericide dosing subsystem, which includes a sodium hypochlorite dosing tank 3 and a sodium hypochlorite dosing pump 2, the outlet of which is connected to the inlet pipe downstream of the flow meter 1; The online residual chlorine meter 4 is located downstream of the sodium hypochlorite dosing point and upstream of the ultraviolet sterilizer 7; The control system 11 is configured to: adjust the dosage of sodium hypochlorite dosing pump 2 according to the preset functional relationship between sodium hypochlorite dosage and influent flow rate, and in combination with the feedback signal of the online residual chlorine meter 4, so as to maintain the measured value of the online residual chlorine meter 4 within the preset range.

[0010] In conjunction with the first aspect, the sensing and detection unit further includes an online turbidimeter 5 disposed upstream of the ultraviolet sterilizer 7, and the control system 11 is configured to: determine and adjust the power of the ultraviolet sterilizer 7 based on the measurement value of the flow meter 1, the measurement value of the online turbidimeter 5, the measurement value of the heterotrophic bacteria count detector 6, and a preset heterotrophic bacteria inactivation rate, according to the ultraviolet dose calculation model.

[0011] In conjunction with the first aspect, the ultraviolet sterilizer 7 is equipped with an ultraviolet intensity sensor, and the control system 11 is configured to: correct and adjust the power setting value of the ultraviolet sterilizer 7 according to the actual ultraviolet intensity signal fed back by the ultraviolet intensity sensor.

[0012] In conjunction with the first aspect, the chemical dosing unit also includes a reducing agent dosing subsystem, which includes a reducing agent dosing tank 10 and a reducing agent dosing pump 9, the outlet of which is connected to the water inlet pipe downstream of the ultraviolet sterilizer 7; The sensing and detection unit also includes an online ORP table 8 located downstream of the ultraviolet sterilizer 7; The control system 11 is configured to dynamically adjust the dosage of the reducing agent dosing pump 9 based on the measured values ​​of the flow meter 1, the online residual chlorine meter 4, and the online ORP meter 8.

[0013] A second aspect of this disclosure provides an optimized dosing method for reverse osmosis based on ultraviolet sterilization, comprising the following steps: S1: Real-time collection of influent flow rate, initial value of heterotrophic bacteria in influent, and residual chlorine value in upstream water of UV sterilizer 7; S2: Dynamically adjust the power of the ultraviolet sterilizer 7 according to the initial value of heterotrophic bacteria and the preset heterotrophic bacteria inactivation rate; S3: Dynamically adjust the dosage of chemical agents added to the influent based on the influent flow rate and the residual chlorine value.

[0014] In conjunction with the second aspect, the chemical agent includes an oxidizing bactericide, and step S3 specifically includes: Feedforward control is performed based on the preset functional relationship between the dosage of oxidizing bactericide and the influent flow rate; With the goal of maintaining the residual chlorine value in the upstream water of the UV sterilizer 7 within a preset range, a PID control algorithm is used to adjust the dosage of the oxidizing disinfectant.

[0015] In conjunction with the second aspect, step S2 specifically includes: Real-time collection of turbidity values ​​of the incoming water; Based on the ultraviolet dose calculation model, the required power setting value of the ultraviolet sterilizer 7 is calculated according to the influent flow rate, the turbidity value, the initial value of heterotrophic bacteria, and the preset heterotrophic bacteria inactivation rate. The power of the ultraviolet sterilizer 7 is adjusted according to the power setting value, and the power is corrected in a closed loop according to the feedback signal of the ultraviolet intensity sensor inside the ultraviolet sterilizer 7.

[0016] In conjunction with the second aspect, the chemical agent further includes a reducing agent, and the method further includes: S4: Real-time acquisition of the oxidation-reduction potential value of the water body downstream of the UV sterilizer 7; S5: Dynamically adjust the dosage of reducing agent added downstream of the UV sterilizer 7 based on the influent flow rate, the residual chlorine value, and the oxidation-reduction potential value.

[0017] In conjunction with the second aspect, the oxidizing bactericide is sodium hypochlorite, the reducing agent is sodium bisulfite, and the preset residual chlorine value range is 0.01-0.05 mg / L.

[0018] Beneficial Effects: This disclosure provides a reverse osmosis optimal dosing system and method based on ultraviolet (UV) sterilization. By integrating a UV sterilizer into the reverse osmosis feed water pipeline and configuring multi-parameter sensors for flow rate, turbidity, heterotrophic bacteria count, residual chlorine, and oxidation-reduction potential, along with a chemical dosing unit interlocked with the control system, the following core operations are achieved: First, the system monitors the influent microbial load and water quality in real time, dynamically calculates the required UV dose, and precisely adjusts the UV sterilizer power. Second, based on the remaining microbial risk after UV treatment and the influent flow rate, a PID control strategy combining feedforward and feedback is used to precisely adjust the dosage of oxidizing disinfectants (such as sodium hypochlorite). Simultaneously, based on the oxidation-reduction potential of the water after sterilization, a reducing agent (such as sodium bisulfite) is intelligently added to protect the reverse osmosis membrane. Ultimately, this achieves highly efficient synergy between UV physical sterilization and chemical sterilization, significantly reducing chemical reagent consumption and operating costs while ensuring strict control of microbial contamination, reducing byproduct generation, extending the service life of the reverse osmosis membrane, and improving the system's intelligent operation and overall economic benefits. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of a reverse osmosis optimized dosing system based on ultraviolet sterilization according to an embodiment of this disclosure; Figure 2 This is a schematic flowchart of an optimized dosing method for reverse osmosis based on ultraviolet sterilization, according to an embodiment of this disclosure. Detailed Implementation

[0020] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with those disclosed herein.

[0021] The terminology used in this disclosure is for the purpose of describing particular embodiments only and is not intended to be limiting of the present disclosure. The singular forms “a,” “the,” and “the” as used in this disclosure and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and includes any and all possible combinations of one or more of the associated listed items.

[0022] Figure 1 This is a schematic diagram of a reverse osmosis optimal dosing system based on ultraviolet sterilization, according to an embodiment of the present disclosure, including: The water inlet pipe is equipped with a flow meter 1 and an ultraviolet sterilizer 7 in sequence. A chemical dosing unit includes at least one dosing device for adding chemical agents to the inlet pipe; The sensing and detection unit includes a heterotrophic bacteria count detector 6 located upstream of the ultraviolet sterilizer 7 and an online residual chlorine meter 4 located on the water inlet pipe; The control system 11 is connected to the flow meter 1, the heterotrophic bacteria count detector 6, the online residual chlorine meter 4, the ultraviolet sterilizer 7, and the chemical dosing unit respectively. The control system 11 is configured as follows: The power of the ultraviolet sterilizer 7 is dynamically adjusted based on the initial heterotrophic bacteria count detected by the heterotrophic bacteria count detector 6 and the preset heterotrophic bacteria inactivation rate. The dosage of chemical reagents in the chemical dosing unit is dynamically adjusted based on the measured values ​​of the flow meter 1 and the online residual chlorine meter 4.

[0023] The system uses the inlet pipe as the main line, with flow meters 1 and ultraviolet sterilizers 7 arranged sequentially along the water flow direction, forming the basic treatment process. The system's intelligent collaborative control relies on three key components: first, a chemical dosing unit, including a device for adding chemicals into the pipe; second, a sensing and detection unit, which innovatively combines a heterotrophic bacteria count meter 6 for monitoring microbial numbers and an online residual chlorine meter 4 for detecting the effectiveness of chemical agents, both located upstream of the ultraviolet sterilizer 7; and third, a control system 11 serving as the command center. This system is connected via electrical signals, integrating data acquisition and command issuance functions. Its core control logic is as follows: the control system 11 dynamically calculates and adjusts the power of the ultraviolet sterilizer 7 based on the initial microbial concentration fed back in real time by the heterotrophic bacteria count meter 6, combined with a preset inactivation rate target, to optimize the physical sterilization effect; simultaneously, it integrates the inlet flow data from the flow meter 1 with the chemical residue level reflected by the online residual chlorine meter 4 to precisely adjust the dosage of the chemical dosing unit in real time and dynamically. Thus, the system achieves the linkage and optimization of ultraviolet physical sterilization and chemical sterilization, aiming to achieve the best microbial control effect with the lowest reagent consumption.

[0024] Furthermore, the chemical dosing unit includes an oxidizing bactericide dosing subsystem, which includes a sodium hypochlorite dosing tank 3 and a sodium hypochlorite dosing pump 2, the outlet of which is connected to the inlet pipe downstream of the flow meter 1. The online residual chlorine meter 4 is located downstream of the sodium hypochlorite dosing point and upstream of the ultraviolet sterilizer 7; The control system 11 is configured to: adjust the dosage of sodium hypochlorite dosing pump 2 according to the preset functional relationship between sodium hypochlorite dosage and influent flow rate, and in combination with the feedback signal of the online residual chlorine meter 4, so as to maintain the measured value of the online residual chlorine meter 4 within the preset range.

[0025] This section further clarifies the specific composition and advanced control logic of a core subsystem within the chemical dosing unit. It concretizes the "chemical dosing unit" as a dosing subsystem for oxidizing bactericides, represented by sodium hypochlorite, consisting of a storage tank 3 and a metering pump 2. Its dosing point is located after the flow meter 1, ensuring a correlation between the dosing amount and the water flow rate. Crucially, the online residual chlorine meter 4 is strategically positioned downstream of the dosing point and upstream of the ultraviolet sterilizer 7, allowing it to directly monitor the immediate effect of chemical sterilization. The focus of this section is revealing a composite control strategy employed by the control system 11: it not only performs feedforward proportional dosing based on the influent flow rate, but more importantly, it introduces the real-time measurement value of the online residual chlorine meter 4 as a feedback signal and uses a PID control algorithm to dynamically and precisely adjust this feedback. Its ultimate control objective is to stabilize the residual chlorine within a narrow, preset optimal range. This directly achieves the goal of minimizing waste or insufficient dosing while meeting sterilization requirements, embodying the core idea of ​​"optimal dosing."

[0026] Furthermore, the sensing and detection unit also includes an online turbidimeter 5 disposed upstream of the ultraviolet sterilizer 7, and the control system 11 is configured to: determine and adjust the power of the ultraviolet sterilizer 7 based on the measurement value of the flow meter 1, the measurement value of the online turbidimeter 5, the measurement value of the heterotrophic bacteria count detector 6, and the preset heterotrophic bacteria inactivation rate, according to the ultraviolet dose calculation model.

[0027] An online turbidity meter 5 was added to the sensing and detection unit, and its measured value was explicitly stated to be one of the key parameters for calculating the ultraviolet dose. This is because the turbidity of the water directly affects the transmittance of ultraviolet light, and thus affects the actual sterilization effect. This section reveals that the control system 11 integrates an ultraviolet dose calculation model. This model no longer simply relies on flow rate or empirical values, but integrates four key variables: flow rate representing the water residence time and flow profile, turbidity affecting ultraviolet penetration, heterotrophic bacteria count characterizing the initial microbial load, and the user-set sterilization target (preset inactivation rate). Through this multi-parameter model, the system can scientifically and dynamically calculate the ultraviolet dose required to achieve the target inactivation rate, and accordingly determine and adjust the power setting value of the ultraviolet lamp, thereby upgrading the physical sterilization process from "experience-based operation" to "model-based precise operation".

[0028] Furthermore, the ultraviolet sterilizer 7 is equipped with an ultraviolet intensity sensor, and the control system 11 is configured to: correct and adjust the power setting value of the ultraviolet sterilizer 7 according to the actual ultraviolet intensity signal fed back by the ultraviolet intensity sensor.

[0029] A status monitoring and closed-loop feedback correction mechanism for the UV sterilizer 7 itself is added. It integrates a UV intensity sensor within the UV sterilizer 7 to directly and in real-time monitor the actual UV light intensity emitted by the lamp. This design is crucial because the light intensity of the UV lamp naturally decreases over time, and scale buildup on the inner wall of the chamber may affect reflection efficiency. Relying solely on the initial power setting cannot guarantee a stable UV dose output throughout its entire lifespan. This section explains that the control system 11 receives the signal from this sensor and compares the actual measured UV intensity with the expected intensity calculated based on the model. If a deviation exists, the system automatically fine-tunes and corrects the power setting. This forms an inner, rapid closed-loop control, ensuring that regardless of changes in the equipment's status, the actual delivered UV sterilization dose remains stable near the target value, greatly improving the long-term reliability and consistency of the system's performance.

[0030] Furthermore, the chemical dosing unit also includes a reducing agent dosing subsystem, which includes a reducing agent dosing tank 10 and a reducing agent dosing pump 9, the outlet of which is connected to the water inlet pipe downstream of the ultraviolet sterilizer 7; The sensing and detection unit also includes an online ORP table 8 located downstream of the ultraviolet sterilizer 7; The control system 11 is configured to dynamically adjust the dosage of the reducing agent dosing pump 9 based on the measured values ​​of the flow meter 1, the online residual chlorine meter 4, and the online ORP meter 8.

[0031] The reducing agent dosing subsystem embodies the protection logic for the reverse osmosis membrane itself. This subsystem consists of a reducing agent (such as sodium bisulfite) dosing tank 10 and a metering pump 9, with its dosing point specifically located downstream of the UV sterilizer 7. Simultaneously, an online ORP meter 8 is added downstream at the same location to monitor the oxidation-reduction potential of the water, a key indicator for determining whether oxidizing substances (such as residual chlorine) in the water have been completely neutralized. This section clarifies the collaborative control strategy of the control system 11 here: it simultaneously considers the influent flow rate (affecting the total volume of water to be treated), the residual chlorine value upstream of the UV sterilizer (reflecting the initial oxidant concentration), and the ORP value downstream of the UV sterilizer (reflecting the final oxidizing level), thereby comprehensively judging and dynamically adjusting the dosage of the reducing agent 9. Its purpose is to ensure that all residual oxidizing disinfectants are effectively neutralized before entering the precision and expensive reverse osmosis membrane components, thereby preventing irreversible damage to the membrane elements caused by chemical oxidation. While pursuing efficient sterilization, it also ensures the safety of core assets, forming a complete pretreatment protection chain.

[0032] like Figure 2 The diagram shown is a flowchart illustrating an optimized dosing method for reverse osmosis based on ultraviolet sterilization, according to an embodiment of this disclosure, including: S1: Real-time collection of influent flow rate, initial value of heterotrophic bacteria in influent, and residual chlorine value in upstream water of UV sterilizer 7; S2: Dynamically adjust the power of the ultraviolet sterilizer 7 according to the initial value of heterotrophic bacteria and the preset heterotrophic bacteria inactivation rate; Step S2 specifically includes: Real-time collection of turbidity values ​​of the incoming water; Based on the ultraviolet dose calculation model, the required power setting value of the ultraviolet sterilizer 7 is calculated according to the influent flow rate, the turbidity value, the initial value of heterotrophic bacteria, and the preset heterotrophic bacteria inactivation rate. The power of the ultraviolet sterilizer 7 is adjusted according to the power setting value, and the power is corrected in a closed loop according to the feedback signal of the ultraviolet intensity sensor inside the ultraviolet sterilizer 7.

[0033] S3: Dynamically adjust the dosage of chemical agents added to the influent based on the influent flow rate and the residual chlorine value.

[0034] The chemical agent includes an oxidizing bactericide, and step S3 specifically includes: Feedforward control is performed based on the preset functional relationship between the dosage of oxidizing bactericide and the influent flow rate; With the goal of maintaining the residual chlorine value in the upstream water of the UV sterilizer 7 within a preset range, a PID control algorithm is used to adjust the dosage of the oxidizing disinfectant.

[0035] The oxidizing bactericide is sodium hypochlorite, the reducing agent is sodium bisulfite, and the preset residual chlorine value range is 0.01-0.05 mg / L.

[0036] The method begins with the real-time acquisition of core operating parameters (S1), including influent flow rate, initial heterotrophic bacteria values ​​reflecting microbial threats, and pre-UV residual chlorine values ​​characterizing chemical residues.

[0037] Subsequently, the method enters the physical sterilization optimization stage (S2). This stage employs an intelligent decision-making process driven by a multivariate model. First, the system collects turbidity values ​​that affect ultraviolet transmittance in real time. Next, the control system invokes the built-in ultraviolet dose calculation model, comprehensively considering four key parameters: influent flow rate (determining water residence time), turbidity value (affecting ultraviolet penetration ability), initial heterotrophic bacteria count (sterilization load), and preset heterotrophic bacteria inactivation rate (sterilization target). This model scientifically calculates the theoretical ultraviolet dose required to achieve the target and converts it into the power setting value for the ultraviolet sterilizer 7. Finally, the system executes a two-layer control: first, it adjusts the power based on this setting value; then, it receives real-time feedback from the ultraviolet intensity sensor inside the ultraviolet sterilizer to perform closed-loop fine-tuning of the power, compensating for light intensity attenuation caused by lamp aging or scaling, ensuring a constant and accurate actual output ultraviolet dose.

[0038] While optimizing physical sterilization, the method concurrently executes a chemical dosing optimization step (S3), specifically targeting oxidizing disinfectants (such as sodium hypochlorite). This step employs a feedforward-feedback composite control strategy. The system first performs rapid feedforward dosing based on the influent flow rate and a preset functional relationship to handle sudden flow changes. More importantly, it directly controls the feedforward dosing by maintaining the residual chlorine level in the upstream water of the UV sterilizer within a very narrow optimal range (e.g., 0.01-0.05 mg / L), using a PID control algorithm to continuously adjust the dosing amount. This ensures that the chemical dosing amount precisely matches the actual remaining demand after UV pretreatment, preventing incomplete sterilization due to insufficient dosing and avoiding waste and byproduct risks caused by overdosing.

[0039] In summary, this method, through steps S1 to S3, constructs a closed-loop optimization system based on real-time multi-parameter sensing and employing model calculation and feedforward-feedback control. Ultimately, it achieves deep synergy between ultraviolet physical sterilization and chemical dosing in terms of dosage and timing, thus achieving the core objective of significantly reducing drug consumption while ensuring sterilization effectiveness.

[0040] Furthermore, the chemical agent also includes a reducing agent, and the method further includes: S4: Real-time acquisition of the oxidation-reduction potential value of the water body downstream of the UV sterilizer 7; S5: Dynamically adjust the dosage of reducing agent added downstream of the UV sterilizer 7 based on the influent flow rate, the residual chlorine value, and the oxidation-reduction potential value.

[0041] This section, building upon the optimized chemical sterilization step S3, adds crucial subsequent protection steps, forming a complete "sterilization-protection" closed-loop process. In step S4, the oxidation-reduction potential (ORP) value of the water is collected in real-time downstream of the UV sterilizer 7. This parameter is a direct indicator of the activity of oxidizing substances in the water (such as residual chlorine not consumed by microorganisms). Step S5 elaborates on the intelligent control logic based on this: the control system does not add reducing agent in isolation based on the ORP value, but comprehensively considers three pieces of information: the influent flow rate (determining the total amount of water to be treated), the residual chlorine value upstream of the UV sterilizer (reflecting the initial oxidant dosage level), and the downstream ORP value (reflecting the final oxidizing state). Through this comprehensive judgment, the system can dynamically and precisely adjust the dosage of reducing agent (such as sodium bisulfite). Its core objective is to ensure that all oxidizing substances are precisely neutralized to a safe level before entering the reverse osmosis membrane module, which is extremely sensitive to oxidative damage. This step seamlessly integrates the pursuit of sterilization effectiveness with the safety protection of core membrane assets. While achieving the goal of efficient pretreatment, it fundamentally eliminates the risk of chemical oxidation damage to the reverse osmosis membrane caused by excessive sterilization or control imbalance, thus achieving a balance between system operating efficiency and long-term safety.

[0042] The above embodiments are only used to illustrate the technical solutions of this disclosure, and are not intended to limit it. Although this disclosure has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this disclosure, and should all be included within the protection scope of this disclosure.

Claims

1. An ultraviolet disinfection based reverse osmosis optimization dosing system, characterized in that, The application relates to a water treatment system, which comprises the following components: a water inlet pipeline, on which a flow meter (1) and an ultraviolet sterilizer (7) are sequentially arranged; a chemical dosing unit, which comprises at least one dosing device for adding chemical agents to the water inlet pipeline; a sensing and detecting unit, which comprises a heterotrophic bacteria number detector (6) arranged upstream of the ultraviolet sterilizer (7) and an online residual chlorine meter (4) arranged on the water inlet pipeline; a control system (11) which is signal-connected with the flow meter (1), the heterotrophic bacteria number detector (6), the online residual chlorine meter (4), the ultraviolet sterilizer (7) and the chemical dosing unit respectively; wherein the control system (11) is configured to: dynamically adjust the power of the ultraviolet sterilizer (7) according to an initial heterotrophic bacteria number value detected by the heterotrophic bacteria number detector (6) and a preset heterotrophic bacteria inactivation rate; dynamically adjust the adding amount of chemical agents in the chemical dosing unit according to the measurement value of the flow meter (1) and the measurement value of the online residual chlorine meter (4).

2. The system of claim 1, wherein, The chemical dosing unit comprises an oxidizing bactericide dosing subsystem, the subsystem comprises a sodium hypochlorite dosing tank (3) and a sodium hypochlorite dosing pump (2), and the outlet of the sodium hypochlorite dosing pump (2) is connected to the water inlet pipeline downstream of the flow meter (1); the online residual chlorine meter (4) is arranged downstream of the sodium hypochlorite dosing point and upstream of the ultraviolet sterilizer (7); the control system (11) is configured to: according to a preset function relationship between the adding amount of sodium hypochlorite and the water inlet flow, and in combination with the feedback signal of the online residual chlorine meter (4), the adding amount of the sodium hypochlorite dosing pump (2) is adjusted through a PID control algorithm, so that the measurement value of the online residual chlorine meter (4) is maintained within a preset range.

3. The system of claim 2, wherein, The sensing and detecting unit further comprises an online turbidity meter (5) arranged upstream of the ultraviolet sterilizer (7), and the control system (11) is configured to: according to the measurement value of the flow meter (1), the measurement value of the online turbidity meter (5), the measurement value of the heterotrophic bacteria number detector (6) and the preset heterotrophic bacteria inactivation rate, the power of the ultraviolet sterilizer (7) is determined and adjusted based on an ultraviolet dose calculation model.

4. The system of claim 3, wherein, An ultraviolet intensity sensor is arranged in the ultraviolet sterilizer (7), and the control system (11) is configured to: according to the actual ultraviolet intensity signal fed back by the ultraviolet intensity sensor, the power set value of the ultraviolet sterilizer (7) is corrected and adjusted.

5. The system of any of claims 2-4, wherein, The chemical dosing unit further comprises a reducing agent dosing subsystem, the subsystem comprises a reducing agent dosing tank (10) and a reducing agent dosing pump (9), and the outlet of the reducing agent dosing pump (9) is connected to the water inlet pipeline downstream of the ultraviolet sterilizer (7); the sensing and detecting unit further comprises an online ORP meter (8) arranged downstream of the ultraviolet sterilizer (7); the control system (11) is configured to: according to the measurement value of the flow meter (1), the measurement value of the online residual chlorine meter (4) and the measurement value of the online ORP meter (8), the adding amount of the reducing agent dosing pump (9) is dynamically adjusted.

6. An ultraviolet disinfection based reverse osmosis optimization dosing method applied to the system according to any one of claims 1-5, characterized in that, The application further discloses a water treatment method, which comprises the following steps: S1: collecting the water inflow, the initial value of the heterotrophic bacteria in the water inflow, and the residual chlorine value in the water upstream of the ultraviolet sterilizer (7) in real time; S2: dynamically adjusting the power of the ultraviolet sterilizer (7) according to the initial value of the heterotrophic bacteria and a preset heterotrophic bacteria inactivation rate; S3: dynamically adjusting the amount of chemical agent added to the water inflow according to the water inflow and the residual chlorine value.

7. The method of claim 6, wherein, The chemical agent includes an oxidizing bactericide, and step S3 specifically includes: performing feedforward control according to a preset functional relationship between the amount of the oxidizing bactericide added and the water inflow; adopting a PID control algorithm to perform feedback adjustment on the amount of the oxidizing bactericide added, with the goal of maintaining the residual chlorine value in the water upstream of the ultraviolet sterilizer (7) within a preset range.

8. The method of claim 7, wherein, Step S2 specifically includes: collecting the turbidity value of the water inflow in real time; calculating the required power set value of the ultraviolet sterilizer (7) according to the water inflow, the turbidity value, the initial value of the heterotrophic bacteria, and a preset heterotrophic bacteria inactivation rate based on an ultraviolet dose calculation model; adjusting the power of the ultraviolet sterilizer (7) according to the power set value and performing closed-loop correction on the power according to the feedback signal of the ultraviolet intensity sensor inside the ultraviolet sterilizer (7).

9. The method of claim 8, wherein, The chemical agent also includes a reducing agent, and the method further includes: S4: collecting the oxidation-reduction potential value of the water downstream of the ultraviolet sterilizer (7) in real time; S5: dynamically adjusting the amount of reducing agent added downstream of the ultraviolet sterilizer (7) according to the water inflow, the residual chlorine value, and the oxidation-reduction potential value.

10. The method of claim 9, wherein, The oxidizing bactericide is sodium hypochlorite, the reducing agent is sodium bisulfite, and the preset residual chlorine value range is 0.01-0.05 mg / L.

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