An automatic oxidant feeding device controlled by an online residual chlorine analyzer

Abstract

The utility model discloses a kind of automatic dosing device of oxidizing agent controlled by online residual chlorine analyzer, including reservoir and membrane system, reservoir is connected membrane system by pipeline, and pipeline between reservoir and membrane system is provided with pipeline mixer and residual chlorine analyzer, pipeline mixer includes pipeline mixer A and pipeline mixer B, pipeline mixer A is connected sodium hypochlorite tank by pipeline and metering pump A, mixed pipeline B is connected sodium bisulfite tank by pipeline and metering pump B, residual chlorine analyzer is set on the pipeline between pipeline mixer A and pipeline mixer B, residual chlorine analyzer, metering pump A and metering pump B are all electrically connected to controller. The utility model is monitored in real time by online residual chlorine analyzer, and controller is automatically adjusted sodium hypochlorite dosing amount and residual chlorine neutralization amount according to feedback signal, to realize the dynamic balance of residual chlorine concentration;Avoid membrane oxidation damage, prolong the life of membrane;Full process does not need manual intervention, improve system stability and operating efficiency.

Description

Technical Field

[0001] This utility model relates to the technical field of automatic dosing devices for membrane separation, and in particular to an automatic dosing device for oxidant controlled by an online residual chlorine analyzer. Background Technology

[0002] Membrane processes (such as reverse osmosis (RO) and nanofiltration (NF)) are one of the core technologies for lithium extraction from salt lakes. The key challenge lies in membrane fouling control. Due to the extremely small pore size of the membranes (approximately 0.1–1 nm for RO membranes and 1–10 nm for NF membranes), suspended solids, colloids, and microorganisms in the feed water easily form a filter cake layer or biofouling on the membrane surface, leading to increased transmembrane pressure gradient (TMP), decreased flux, and even irreversible damage to the membrane structure. Especially in salt lake brine systems, high salinity and eutrophication easily breed microorganisms (such as algae and bacteria), whose metabolic products (such as extracellular polymeric substances, EPS) accelerate biofilm formation and significantly shorten the lifespan of RO / NF membranes.

[0003] Currently, the industry commonly uses sodium hypochlorite (NaClO) to disrupt microbial cell membranes and enzyme systems, inhibiting biological activity. However, excessive sodium hypochlorite addition leads to increased residual chlorine (free chlorine) concentration, triggering oxidative degradation of membrane materials (such as polyamide composite membranes). Existing residual chlorine concentration control mainly relies on manual experience to adjust the sodium hypochlorite dosage, which has the following drawbacks: it cannot monitor residual chlorine concentration dynamically in real time, resulting in low dosage accuracy; it lacks a closed-loop feedback control mechanism, easily leading to excessive fluctuations in residual chlorine concentration; and it lacks an emergency neutralization device in case of excessive residual chlorine, resulting in a high risk of membrane damage. Utility Model Content

[0004] The purpose of this invention is to address the shortcomings of existing technologies by proposing an automatic oxidant dosing device that utilizes an online residual chlorine analyzer.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] An automatic oxidant dosing device controlled by an online residual chlorine analyzer includes a storage tank and a membrane system. The storage tank is connected to the membrane system via a pipeline. A pipeline mixer and a residual chlorine analyzer are installed on the pipeline between the storage tank and the membrane system. The pipeline mixer includes pipeline mixer A and pipeline mixer B. Pipeline mixer A is connected to a sodium hypochlorite tank via a pipeline. A metering pump A is installed on the pipeline between pipeline mixer A and the sodium hypochlorite tank. Pipeline mixer B is connected to a sodium bisulfite tank via a pipeline. A metering pump B is installed on the pipeline between pipeline mixer A and pipeline mixer B. The residual chlorine analyzer, metering pump A, and metering pump B are all electrically connected to a controller.

[0007] Preferably, the residual chlorine analyzer is an online residual chlorine analyzer. The online residual chlorine analyzer feeds back the concentration of residual chlorine detected in the pipeline to the controller. The controller controls the opening of the metering pump B to realize the automatic addition of sodium bisulfite, which neutralizes the residual chlorine through a redox reaction and avoids membrane damage.

[0008] Preferably, both ends of metering pump A and metering pump B are equipped with solenoid valves, which are connected to a controller, and the controller controls the opening and closing of the solenoid valves.

[0009] Preferably, both pipe mixer A and pipe mixer B are static mixers.

[0010] Preferably, a pressure sensor is installed on the main pipeline between the storage tank and the membrane system. The pressure sensor is electrically connected to the controller and is used to monitor the transmembrane pressure difference of the membrane system.

[0011] Preferably, the controller has a built-in PID control algorithm, which can automatically adjust the opening degree of metering pump A and metering pump B according to the difference between the real-time concentration fed back by the residual chlorine analyzer and the preset threshold.

[0012] The beneficial effects of this utility model are as follows:

[0013] Real-time monitoring via an online residual chlorine analyzer allows the controller to automatically adjust the sodium hypochlorite dosage and residual chlorine neutralization amount based on feedback signals, achieving a dynamic balance of residual chlorine concentration. Sodium hypochlorite inhibits biofouling, while sodium bisulfite neutralizes excess residual chlorine in emergencies, preventing membrane oxidative damage and extending membrane life. The entire process requires no manual intervention, with solenoid valves and metering pumps working in tandem to improve system stability and operational efficiency. Attached Figure Description

[0014] Figure 1 This is a structural diagram of the device of this utility model;

[0015] In the diagram: 1. Storage tank; 2. Pipeline mixer A; 3. Pipeline mixer B; 4. Residual chlorine analyzer; 5. Sodium bisulfite tank; 6. Sodium hypochlorite tank; 7. Controller; 8. Metering pump A; 9. Metering pump B; 10. Membrane system. Detailed Implementation

[0016] The technical solution of this utility model will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0017] Example 1

[0018] like Figure 1As shown, this utility model provides an automatic oxidant dosing device controlled by an online residual chlorine analyzer. Its structure includes a storage tank 1 and a membrane system 10. The storage tank 1 is connected to the membrane system 10 via a pipeline. A pipeline mixer and a residual chlorine analyzer 4 are installed on the pipeline between the storage tank 1 and the membrane system 10. The pipeline mixer includes a pipeline mixer A2 and a pipeline mixer B3. Pipeline mixer A2 is connected to a sodium hypochlorite tank 6 via a pipeline. A metering pump A8 is installed on the pipeline between pipeline mixer A2 and the sodium hypochlorite tank 6. Pipeline mixer B3 is connected to a sodium bisulfite tank 5 via a pipeline. A metering pump B9 is installed on the pipeline between pipeline mixer B3 and the sodium bisulfite tank 5. The residual chlorine analyzer 4 is installed on the pipeline between pipeline mixer A2 and pipeline mixer B3. The residual chlorine analyzer 4, metering pump A8, and metering pump B9 are all electrically connected to a controller 7.

[0019] The residual chlorine analyzer 4 is an online residual chlorine analyzer 4. The online residual chlorine analyzer 4 feeds back the concentration of residual chlorine detected in the pipeline to the controller 7, and the controller 7 controls the opening of the metering pump B9.

[0020] Both ends of metering pump A8 and metering pump B9 are equipped with solenoid valves, which are connected to controller 7. Controller 7 controls the opening and closing of the solenoid valves.

[0021] Both pipe mixer A2 and pipe mixer B3 are static mixers;

[0022] A pressure sensor is installed on the main pipeline between the storage tank 1 and the membrane system 10, and the pressure sensor is electrically connected to the controller 7.

[0023] The controller 7 has a built-in PID control algorithm.

[0024] Working principle:

[0025] Based on the operating flow rate of the membrane system, the controller presets the initial dosing rate of metering pump A to 5L / h. Sodium hypochlorite flows with the water through pipe mixer A and mixes with the brine to inhibit microbial contamination.

[0026] The online residual chlorine analyzer monitors the residual chlorine concentration in the pipeline in real time and transmits the data to the controller.

[0027] If the residual chlorine concentration is <0.3 mg / L, the controller increases the opening of metering pump A to increase the sodium hypochlorite dosage;

[0028] If the residual chlorine concentration is >0.3 mg / L, the controller starts metering pump B to add sodium bisulfite, which neutralizes the excess residual chlorine through the reaction "NaHSO3 + HClO = NaHSO4 + HCl".

[0029] When the pressure sensor detects that TMP exceeds 0.5MPa, the controller automatically triggers an alarm and increases the dosage of sodium hypochlorite to enhance the sterilization effect, while recording the data for later analysis.

Claims

1. A device for automatically adding oxidant using an online residual chlorine analyzer, characterized in that: The system includes a storage tank and a membrane system. The storage tank is connected to the membrane system via a pipeline. A pipeline mixer and a residual chlorine analyzer are installed on the pipeline between the storage tank and the membrane system. The pipeline mixer includes pipeline mixer A and pipeline mixer B. Pipeline mixer A is connected to a sodium hypochlorite tank via a pipeline. A metering pump A is installed on the pipeline between pipeline mixer A and the sodium hypochlorite tank. Pipeline mixer B is connected to a sodium bisulfite tank via a pipeline. A metering pump B is installed on the pipeline between pipeline mixer A and pipeline mixer B. The residual chlorine analyzer, metering pump A, and metering pump B are all electrically connected to a controller.

2. The automatic oxidant dosing device controlled by an online residual chlorine analyzer according to claim 1, characterized in that: The residual chlorine analyzer is an online residual chlorine analyzer.

3. The automatic oxidant dosing device controlled by an online residual chlorine analyzer according to claim 1, characterized in that: Both ends of metering pump A and metering pump B are equipped with solenoid valves, which are connected to the controller.

4. The automatic oxidant dosing device controlled by an online residual chlorine analyzer according to claim 1, characterized in that: Both pipe mixer A and pipe mixer B are static mixers.

5. The automatic oxidant dosing device controlled by an online residual chlorine analyzer according to claim 1, characterized in that: A pressure sensor is installed on the main pipeline between the storage tank and the membrane system, and the pressure sensor is electrically connected to the controller.

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