Front crystal nucleus inhibition device of reverse osmosis membrane

Abstract

The invention discloses a reverse osmosis membrane front crystal nucleus inhibition device which comprises a pH adjusting mechanism, a calcium sulfate crystallization reactor, a crystal separation mechanism and an adjusting mechanism which are sequentially arranged in the water flow direction, and the pH adjusting mechanism comprises a metering and adding device and an ultrasonic disperser which are sequentially arranged in the water flow direction; the calcium sulfate crystallization reactor is arranged beside the ultrasonic disperser, a stirring mechanism is arranged in the calcium sulfate crystallization reactor, concentration sensors are arranged at an inlet and an outlet of the calcium sulfate crystallization reactor respectively and used for monitoring calcium ions and sulfate ions, and the crystal separation mechanism comprises a microfiltration membrane assembly and a filter. The microfiltration membrane assembly is connected with an outlet of the calcium sulfate crystallization reactor and used for receiving a solid-liquid mixture, the filter is connected with the microfiltration membrane assembly, and the adjusting mechanism comprises a controller, a front online pH sensor array, a rear online pH sensor array and a concentration sensor. The controller is electrically connected with the front on-line pH sensor array, the rear on-line pH sensor array, the concentration sensor, the ultrasonic disperser, the metering and adding device and the stirring mechanism. The device for inhibiting the crystal nucleus in front of the reverse osmosis membrane has the advantages of eliminating scaling on the membrane surface and improving the recovery rate of raw water.

Description

Technical Field

[0001] This invention relates to the field of water treatment technology, and in particular to a reverse osmosis membrane pre-crystal nucleation suppression device. Background Technology

[0002] When reverse osmosis technology is used for the concentration of mine water and brackish water, high concentrations of calcium and sulfate ions in the raw water easily crystallize due to supersolubility product during concentration. These crystal nuclei form at micropores or defects on the membrane surface, rapidly grow, and accumulate, forming a dense scale layer on the membrane surface that is difficult to remove through conventional chemical cleaning or physical backwashing. Membrane scaling severely clogs membrane pores, leading to decreased system permeate flow and increased energy consumption. Frequent and intensive chemical cleaning to remove the scale layer irreversibly damages the polyamide membrane layer, significantly shortening the membrane element's lifespan.

[0003] By increasing the discharge rate of the concentrate to reduce the concentration factor, the concentration of sparingly soluble salts can be maintained below saturation solubility. This method is simple but directly leads to a significant decrease in water recovery rate (typically below 60%), resulting in serious water waste.

[0004] Adding chemical scale inhibitors, specifically polymer scale inhibitors, to the feed water inhibits crystal nucleation and growth through chelation, dispersion, or lattice distortion. This method is currently the mainstream technology, but it suffers from high operating costs, poor effectiveness, secondary environmental pollution, and the potential for organic fouling of the membrane surface with long-term use. Existing technologies mostly focus on "inhibiting" or "delaying" the crystallization process on the membrane surface. Therefore, there is an urgent need to develop a technology that can actively and controllably complete the crystallization process of sparingly soluble salts before they enter the reverse osmosis membrane module and separate them from the water, thereby eliminating the potential for scale buildup on the membrane surface. Summary of the Invention

[0005] This invention is based on the inventor's discoveries and understanding of the following facts and problems: The scaling of sparingly soluble salts on the surface of reverse osmosis membranes is not effective in inhibiting or delaying crystallization.

[0006] The present invention aims to at least partially solve one of the technical problems in the related art.

[0007] Therefore, embodiments of the present invention propose a reverse osmosis membrane pre-crystallization suppression device, comprising a pH adjustment mechanism, a calcium sulfate crystallization reactor, a crystal separation mechanism, and an adjustment mechanism arranged sequentially along the water flow direction. The pH adjustment mechanism includes a metering dosing device and an ultrasonic disperser arranged sequentially along the water flow direction. The calcium sulfate crystallization reactor is arranged beside the ultrasonic disperser, and a stirring mechanism is provided inside the calcium sulfate crystallization reactor. Concentration sensors are respectively installed at the inlet and outlet of the calcium sulfate crystallization reactor to monitor calcium ions and sulfate ions. The crystal separation mechanism includes a microfiltration membrane assembly and a filter. The microfiltration membrane assembly is connected to the outlet of its respective calcium sulfate crystallization reactor to receive a solid-liquid mixture. The filter is connected to the microfiltration membrane assembly. The adjustment mechanism includes a controller, a front online pH sensor array, a rear online pH sensor array, and a concentration sensor. The controller is electrically connected to the front online pH sensor array, the rear online pH sensor array, the concentration sensor, the ultrasonic disperser, the metering dosing device, and the stirring mechanism.

[0008] The present invention has the advantages and technical effects of eliminating membrane surface scaling and improving raw water recovery rate. This application has the following advantages: Crystallization kinetics shows that at the membrane surface, the solid-liquid interface, the energy barrier for heterogeneous nucleation is much lower than that for homogeneous nucleation in solution. Therefore, the membrane surface is the region most prone to crystallization. Theoretically, when Ca... 2+ ≥300mg / L, SO4 2- Calcium sulfate exhibits a certain tendency for heterogeneous crystallization at concentrations ≥1000 mg / L under appropriate reaction conditions. However, in practical applications, factors such as ion concentration, pH, and reaction conditions limit the effective control of heterogeneous crystallization of calcium sulfate, leading to situations where effective crystallization fails or crystallization occurs too rapidly, resulting in fine particles that pollute the water. This application transfers the crystallization process from the membrane surface to a pre-treatment calcium sulfate crystallization reactor. Through active and controllable induced crystallization, most scale-forming ions are removed before water enters the membrane module, eliminating scale formation on the membrane surface at its source and ensuring the long-term stable operation of the reverse osmosis system. In some embodiments, the metering and dosing device includes an alkali storage tank, a peristaltic pump, and a mixing pipeline. The alkali storage tank is connected to a first end of the mixing pipeline, the peristaltic pump is arranged on the mixing pipeline, and the second end of the mixing pipeline dispenses alkali into the raw water. The metering and dosing device, through the combination of the alkali storage tank, the peristaltic pump, and the mixing pipeline, achieves stable storage and precise metering of alkali, providing a reliable supply of reagents for raw water pH adjustment.

[0009] In some embodiments, the ultrasonic disperser is located adjacent to the second end of the mixing pipeline. The ultrasonic disperser's proximity to the dosing point in the mixing pipeline allows for rapid and uniform dispersion and mixing of the added alkali with the raw water, preventing localized excessively high or low alkalinity and improving the uniformity and stability of pH adjustment.

[0010] In some embodiments, the stirring mechanism includes a propeller impeller and a frequency converter. The propeller impeller is located inside the calcium sulfate crystallization reactor, and the frequency converter is drivenly connected to the propeller impeller. By adjusting the impeller speed via frequency conversion, the stirring intensity inside the reactor can be flexibly controlled, ensuring uniform distribution of the inducer and sufficient crystallization reaction. In some embodiments, a turbidity sensor is also included, which is disposed within the calcium sulfate crystallization reactor and electrically connected to the controller. The turbidity sensor can monitor changes in turbidity within the reactor in real time, providing data for precise control by the controller and ensuring a stable and controllable crystallization process.

[0011] In some embodiments, the calcium sulfate crystallization reactor is a cylindrical tank with a spiral heat exchange tube installed on the tank jacket. The spiral heat exchange tube is connected to a constant temperature water tank. The heat exchange tube and the constant temperature water tank control the temperature inside the reactor, providing a suitable and stable temperature environment for the calcium sulfate crystallization reaction. At the same time, the cylindrical structure facilitates smooth water flow and improves the uniformity of crystallization.

[0012] In some embodiments, an induction inlet is provided at the top of the calcium sulfate crystallization reactor. The induction inlet is a mixture of an inert induction agent and a homogeneous induction agent. The induction inlet facilitates precise induction agent addition, and the mixture of inert and homogeneous induction agents provides sufficient suitable nucleation sites, effectively promoting the nucleation and growth of calcium sulfate crystals and improving crystallization efficiency.

[0013] In some embodiments, the filter further includes a hydrocyclone separator and a sand filter. The inlet of the hydrocyclone separator is connected to the bottom of the calcium sulfate crystallization reactor, and the outlet of the hydrocyclone separator is connected to the inlet of the sand filter. The series connection of the hydrocyclone separator and the sand filter enables efficient, graded separation of crystallized particles. Large crystal particles are first removed by the hydrocyclone, and then finely purified by the sand filter, improving the quality of the effluent and preventing crystallized particles from entering subsequent systems and causing pollution.

[0014] An embodiment of the present invention provides a method for inhibiting crystal nuclei before reverse osmosis membranes, comprising the following steps: The inlet pump is started, and the raw water to be treated flows in. The raw water flows through the front online pH sensor array, which measures the pH value of the raw water in real time and sends the data to the controller of the regulating mechanism. The controller calculates the required dosage of alkali agent based on real-time data from the online pH sensor array and the target pH value. The metering and dosing device draws alkali from the alkali storage tank and injects it into the mixing pipeline; At the point where the raw water enters the mixing pipeline, the ultrasonic disperser is activated to generate high-frequency vibrations to evenly mix the alkali agent with the raw water. Based on the raw water quality, an inducing agent is selected and added to the calcium sulfate crystallization reactor at a preset concentration. The propeller in the calcium sulfate crystallization reactor is then started to ensure that the inducing agent is evenly distributed in the calcium sulfate crystallization reactor, providing a large number of nucleation sites for the crystallization process. After pH adjustment and ultrasonic mixing, the water flows into the calcium sulfate crystallization reactor. The propeller in the calcium sulfate crystallization reactor is continuously stirred by a speed controlled by a frequency converter to ensure that the Reynolds number of the water flow in the reactor is always greater than 6000, thus forming a sufficient turbulent state. Water flowing through the alkali dosing area passes through an online pH sensor array, which measures the adjusted pH value and feeds it back to the controller. The controller compares the adjusted value with the target value and adjusts the dosing rate of the peristaltic pump to form a closed-loop pH control. Concentration sensors installed at the inlet and outlet of the calcium sulfate crystallization reactor monitor changes in the concentration of calcium and sulfate ions in the water flow. The controller calculates the saturation index and removal rate of calcium sulfate in real time based on the data to evaluate the crystallization efficiency.

[0015] In some embodiments, the controller adjusts the variable frequency drive to change the speed of the propeller impeller based on real-time data from the turbidity reactor within the calcium sulfate reactor. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of the reverse osmosis membrane pre-crystal nucleation suppression device according to an embodiment of the present invention.

[0017] Reference numerals in the attached figures: 1. Automatic pH adjustment module; 1.1. Front-end online pH sensor array; 1.2. Metering and dosing device; 1.3. Ultrasonic disperser; 1.4. Back-end online pH sensor array; 2. Calcium sulfate crystallization reactor; 2.1. Concentration sensor; 2.2. Variable frequency drive; 3. Crystal separation unit. Detailed Implementation

[0018] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0019] This invention provides a reverse osmosis membrane pre-crystallization suppression device, comprising a pH adjustment mechanism, a calcium sulfate crystallization reactor 2, a crystal separation mechanism, and an adjustment mechanism arranged sequentially along the water flow direction. The pH adjustment mechanism includes a metering and dosing device 1.2 and an ultrasonic disperser 1.3 arranged sequentially along the water flow direction. The calcium sulfate crystallization reactor 2 is located downstream of the ultrasonic disperser 1.3. A stirring mechanism is installed inside the calcium sulfate crystallization reactor 2. Concentration sensors 2.1 are installed at the inlet and outlet of the calcium sulfate crystallization reactor 2 to monitor calcium ions and sulfate ions, respectively. The crystal separation mechanism includes a microfiltration membrane assembly and a filter. The microfiltration membrane assembly is connected to the outlet of the calcium sulfate crystallization reactor 2 to receive solid-liquid mixtures. The filter is connected to the microfiltration membrane assembly. The adjustment mechanism includes a controller, a front-end online pH sensor array 1.1, a rear-end online pH sensor array 1.4, and a concentration sensor 2.1. The controller is electrically connected to the front-end online pH sensor array 1.1, the rear-end online pH sensor array 1.4, the concentration sensor 2.1, the ultrasonic disperser 1.3, the metering and dosing device 1.2, and the stirring mechanism.

[0020] A pH adjustment mechanism, a calcium sulfate crystallization reactor 2, a crystal separation mechanism, and an adjustment mechanism are arranged sequentially along the water flow direction. The pH adjustment mechanism includes a metering dosing device 1.2 and an ultrasonic disperser 1.3 arranged sequentially along the water flow direction. The metering dosing device 1.2 dispenses a 5%-10% concentration of calcium hydroxide suspension. The ultrasonic disperser 1.3 is located near the alkali dosing point in the mixing pipeline and generates high-frequency vibrations to disperse the alkali particles, achieving microscopic uniform mixing with the raw water, avoiding excessively high local alkalinity and increasing the supersaturation of calcium and sulfate ions. An online pH sensor array at the front is used to monitor the initial pH value of the raw water in real time, and an online pH sensor array at the back captures the pH data after adjustment. Both provide support for the controller to calculate the alkali dosage and fine-tune the dosing rate, ensuring that the water quality pH is stable within the target range of 8.0-8.5. The calcium sulfate crystallization reactor 2 is located downstream of the ultrasonic disperser 1.3. An inducer is added inside to induce crystal growth. The stirring mechanism dynamically adjusts its rotation speed according to controller commands, ensuring a Reynolds number greater than 6000 within the reactor to create sufficient turbulence. This allows supersaturated ions in the raw water to efficiently contact the inducer and form uniform micron-sized crystals. Concentration sensors 2.1 at the reactor inlet and outlet not only monitor the concentrations of calcium and sulfate ions in real time but also, in conjunction with real-time water temperature, provide the controller with data to calculate the calcium sulfate saturation index and removal rate to assess crystallization efficiency. The controller integrates all monitoring data and issues control commands to coordinate the efficient synergy of pH adjustment, crystallization reaction, and crystal separation, eliminating the risk of scaling on the reverse osmosis membrane and achieving high system recovery and long-term stable operation.

[0021] The present invention has the advantages and technical effects of eliminating membrane scaling and improving raw water recovery rate.

[0022] In some embodiments, the metering and dosing device 1.2 includes an alkali storage tank, a peristaltic pump, and a mixing pipeline. The alkali storage tank is connected to a first end of the mixing pipeline, the peristaltic pump is arranged on the mixing pipeline, and the second end of the mixing pipeline dispenses alkali into the raw water.

[0023] Specifically, the alkali storage tank adopts a sealed tank structure. The inner wall of the tank is coated with an anti-fouling coating, and the bottom has a conical flow guide structure to facilitate the full discharge of alkali and avoid residual sedimentation. The mixing pipeline is made of alkali-resistant corrosion-resistant material, and the pipe diameter is adapted to the treatment flow rate. The smooth inner wall of the pipeline reduces alkali flow resistance and adhesion sites. The peristaltic pump is driven by a high-precision stepper motor, which can accurately respond to the dosing command of the controller, ensuring that the dosage of alkali added to the raw water at the second end of the mixing pipeline is consistent with the calculated value.

[0024] Optionally, the second end of the mixing pipeline has a multi-outlet diversion structure, with multiple dosing outlets evenly distributed around the circumference of the raw water pipeline, so that the alkali can be injected into the raw water simultaneously from different directions, further improving the initial mixing uniformity with the raw water and avoiding the problem of local high concentration that may occur at a single dosing point.

[0025] In some embodiments, the ultrasonic diffuser 1.3 is located adjacent to the second end of the mixing conduit.

[0026] Specifically, the distance between the center of the ultrasonic probe of the ultrasonic disperser 1.3 and the alkaline agent dosing outlet at the second end of the mixing pipeline is controlled at 0.5-2cm, and the probe is oriented towards the water flow direction of the dosing outlet to ensure that the alkaline agent is immediately in the core area of ​​ultrasonic action when it is injected into the raw water.

[0027] Optionally, a sliding guide rail and a distance sensor are installed between the second end of the mixing pipeline and the ultrasonic disperser 1.3. The distance sensor monitors the distance between the two in real time and transmits the data to the controller. The controller adjusts the position of the disperser according to the raw water quality (such as turbidity and alkali concentration). When the alkali dosage increases, the disperser is controlled to move closer to the dosing outlet (minimum distance 0.5cm) to enhance the mixing effect. When the dosage decreases, the distance is appropriately increased (maximum distance 2cm) to avoid wasting ultrasonic energy.

[0028] In some embodiments, the stirring mechanism includes a propeller impeller and a frequency converter 2.2. The propeller impeller is located inside the calcium sulfate crystallization reactor 2, and the frequency converter 2.2 is connected to the propeller impeller drive.

[0029] Specifically, the propeller impeller adopts a symmetrical three- or four-blade structure with a blade inclination angle of 15°-25°. It is made of high-strength, wear-resistant stainless steel, and the blade edges are rounded to enhance axial thrust and strengthen turbulent mixing while avoiding excessive shearing of the crystals. The impeller is installed on the central axis of the calcium sulfate crystallization reactor 2, at a distance of 1 / 4 to 1 / 3 of the tank height from the bottom, ensuring coverage of the core reaction area and avoiding dead zones in the stirring. The frequency converter 2.2 is connected to the propeller impeller via a high-strength drive shaft and coupling, which protects the output shaft of the frequency converter 2.2.

[0030] In some embodiments, a turbidity sensor is also included, which is arranged inside the calcium sulfate crystallization reactor 2 and electrically connected to the controller.

[0031] Specifically, the turbidity sensor is positioned within the calcium sulfate crystallization reactor 2, avoiding the rotation trajectory of the impeller and maintaining a 5-10 cm distance from the reactor wall to prevent interference from water vortices and bubbles generated by the impeller's agitation. The turbidity sensor is electrically connected to the controller via a waterproof, sealed cable, providing real-time feedback of the turbidity data of the water within the reactor. This data directly reflects the amount of crystals formed, their growth state, and the uniformity of their distribution, providing crucial monitoring data for the dynamic control of the crystallization process.

[0032] In some embodiments, the calcium sulfate crystallization reactor 2 is a cylindrical tank with a spiral heat exchange tube installed on the tank jacket, and the spiral heat exchange tube is connected to a constant temperature water tank.

[0033] The cylindrical tank of the calcium sulfate crystallization reactor 2 is surrounded by a sealed jacket, which forms an independent cavity with the outer wall of the tank. The spiral heat exchange tube is fixed in the jacket cavity, closely attached to the inner wall of the tank. Its spiral angle is designed to be 10°-15°, and the tube diameter is adapted to the tank specifications from 20-50mm to ensure that the heat exchange tube is fully fitted to the tank to improve the heat conduction efficiency. The inlet and outlet of the spiral heat exchange tube are sealed and connected to the outlet and return of the constant temperature water tank through flanges, respectively. The pipeline is equipped with a shut-off valve and a flow regulating valve to realize the circulation control of the heat exchange medium. The heat exchange tubes are made of corrosion-resistant stainless steel or titanium alloy with excellent thermal conductivity, suitable for alkaline environments with a pH of 8.0-8.5, thus avoiding corrosion during long-term use. The constant temperature water tank is equipped with a heating module, a cooling module, and a temperature sensor, with a temperature control accuracy of ±0.5℃. It can continuously provide a constant temperature heat exchange medium (such as clean water or heat transfer oil) for the spiral heat exchange tubes. The temperature of the reaction water in the tank is regulated by heat conduction to avoid temperature fluctuations that could lead to uncontrolled crystallization rate, thus providing a stable temperature environment for the uniform nucleation and growth of calcium sulfate crystals.

[0034] In some embodiments, an induction inlet is provided at the top of the calcium sulfate crystallization reactor 2, and the induction agent is a mixture of an inert induction agent and a homogeneous induction agent.

[0035] Specifically, an adjustable flow metering valve is arranged at the inlet of the calcium sulfate crystallization reactor 2 at the top to facilitate control of the induction rate. The inlet position corresponds to the rotation area of ​​the propeller impeller, ensuring that the induction is quickly carried by the turbulent water flow and evenly diffused throughout the reaction zone, avoiding localized accumulation. As a mixture of inert and homogeneous induction agents, the mixing ratio needs to be adjusted according to the concentrations of calcium and sulfate ions in the raw water. The inert induction agent is selected from spherical silica microspheres or α-alumina micropowder with a particle size of 1-5 μm, providing stable physical nucleation sites for crystallization. The homogeneous induction agent is selected from calcium sulfate seed powder with a particle size of less than 10 μm, accelerating crystal epitaxial growth through the "seed effect." The synergistic effect of the two ensures both nucleation efficiency and promotes uniform crystal growth, forming easily separable micron-sized particles.

[0036] Optionally, a dual-channel independent dosing system is installed at the induction inlet to deliver inert and homogeneous induction agents respectively. Metering pumps are installed on each channel, and the controller dynamically adjusts the dosing ratio of the two induction agents based on real-time data from the turbidity sensor and ion concentration sensor 2.1 within the reactor. When the raw water ion concentration is high (urgent need for nucleation), the proportion of homogeneous induction is increased (up to 60%) to accelerate the crystallization rate; when the raw water ion concentration is low (need to improve nucleation stability), the proportion of inert induction is increased (up to 70%) to ensure sufficient and uniform nucleation sites, achieving precise adaptation of the mixed induction agents.

[0037] In some embodiments, the filter further includes a hydrocyclone separator and a sand filter, wherein the inlet of the hydrocyclone separator is connected to the bottom of the calcium sulfate crystallization reactor 2, and the outlet of the hydrocyclone separator is connected to the inlet of the sand filter.

[0038] Specifically, the inlet of the hydrocyclone separator is connected to the bottom of the calcium sulfate crystallization reactor 2 via a pipe, ensuring a tight seal to prevent leakage of alkaline water. This directly draws in large, easily settling crystal particles from the bottom of the reactor, reducing the risk of scale buildup. A slow-flow section is incorporated into the pipe to prevent crystal breakage due to water flow impact. The outlet of the hydrocyclone separator is sealed to the inlet of the sand filter via a pressurized pipe. The water flow after hydrocyclone separation (containing a small amount of fine crystals) smoothly enters the sand filter, preventing impact on the filter media and loosening. The process involves coarse separation followed by fine separation. The hydrocyclone separator uses centrifugal force to quickly separate large crystal particles ≥2μm, while the sand filter uses multiple layers of filter media to retain remaining fine crystals ≥0.5μm. Together, they improve the crystal retention rate, ensuring the effluent quality meets the requirements for reverse osmosis membrane feed water. Both the hydrocyclone separator and the sand filter are made of alkali-resistant materials to prevent corrosion during long-term operation.

[0039] An embodiment of the present invention provides a method for inhibiting crystal nuclei before reverse osmosis membranes, comprising the following steps: The inlet pump is started, and the raw water to be treated flows in. The raw water flows through the online pH sensor array 1.1, which measures the pH value of the raw water in real time and sends the data to the controller of the regulating mechanism. The controller calculates the required dosage of alkali based on the real-time data from the online pH sensor array 1.1 and the target pH value; the alkali is a Ca(OH)2 suspension with a concentration of 5%-10%, and the dosage is controlled within the range of 0-20 mg / L.

[0040] The metering and dosing device 1.2 draws alkali from the alkali storage tank and injects it into the mixing pipeline; At the dosing point where the raw water enters the mixing pipeline, the ultrasonic disperser 1.3 is activated to generate high-frequency vibrations to uniformly mix the alkali agent with the raw water; Based on the raw water quality, an inducing agent is selected and added to the calcium sulfate crystallization reactor 2 at a preset concentration. The propeller in the calcium sulfate crystallization reactor 2 is started to make the inducing agent evenly distributed in the calcium sulfate crystallization reactor 2, providing a large number of nucleation sites for the crystallization process. After pH adjustment and ultrasonic mixing, the water flows into the calcium sulfate crystallization reactor 2. The propeller in the calcium sulfate crystallization reactor 2 continuously stirs the water at a speed controlled by the variable frequency drive 2.2 to ensure that the Reynolds number of the water flow in the reactor is always greater than 6000, thus forming a sufficient turbulent state. After the water flows through the alkaline dosing area, the online pH sensor array 1.4 measures the adjusted pH value and feeds it back to the controller. The controller compares it with the target value and adjusts the dosing rate of the peristaltic pump to form a pH closed-loop control. Concentration sensors 2.1 installed at the inlet and outlet of the calcium sulfate crystallization reactor 2 monitor the changes in the concentration of calcium ions and sulfate ions in the water flow. The controller calculates the saturation index and removal rate of calcium sulfate in real time based on the data and evaluates the crystallization efficiency.

[0041] After the system is first run or maintained, check the integrity of the pH adjustment mechanism, calcium sulfate crystallization reactor 2, crystal separation mechanism and all pipeline connections. Ensure that the controller of the adjustment mechanism is powered on and that all sensors (front online pH sensor array, rear online pH sensor array, concentration sensor 2.1, turbidity sensor) and peristaltic pump, frequency converter 2.2, and ultrasonic disperser 1.3 are in standby mode.

[0042] In some embodiments, the controller adjusts the variable frequency drive 2.2 to change the speed of the propeller impeller based on real-time data from the turbidity reactor inside the calcium sulfate reactor.

[0043] Specifically, the controller receives real-time turbidity data from the turbidity sensor inside the calcium sulfate crystallization reactor 2 to determine the nucleation amount, growth state, and uniformity of crystal distribution within the reactor. Low turbidity data indicates insufficient crystal nucleation or uneven dispersion of the inducer; excessively high turbidity data or rapid turbidity increase suggests excessive crystal formation or breakage due to excessive shear force; stable turbidity within the preset range indicates normal crystallization. Based on this judgment, the controller sends a speed adjustment command to the variable frequency drive 2.2, changing its output frequency and regulating the rotational speed of the impeller: increasing the speed to enhance turbulent mixing and promote collisions between supersaturated ions and the inducer when nucleation is insufficient; decreasing the speed to reduce shear force and ensure uniform crystal growth when crystallization is stable; and maintaining a constant speed to ensure a stable flow field when crystallization is stable.

[0044] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0045] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0046] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0047] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "beneath" of the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0048] In this invention, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0049] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A reverse osmosis membrane pre-nucleation inhibition device, characterized by, It comprises: pH adjusting mechanism, calcium sulfate crystallization reactor, crystal separation mechanism and adjusting mechanism arranged in sequence along the direction of water flow, the pH adjusting mechanism comprises dosing device and ultrasonic disperser arranged in sequence along the direction of water flow; the calcium sulfate crystallization reactor is arranged downstream of the ultrasonic disperser, a stirring mechanism is arranged in the calcium sulfate crystallization reactor, and a concentration sensor is arranged at the inlet and outlet of the calcium sulfate crystallization reactor respectively to monitor calcium ions and sulfate ions; the crystal separation mechanism comprises a microfiltration membrane assembly and a filter, the microfiltration membrane assembly is connected with the outlet of the calcium sulfate crystallization reactor to receive solid-liquid mixture, the filter is connected with the microfiltration membrane assembly, and the adjusting mechanism comprises a controller, a front online pH sensor array, a rear online pH sensor array and a concentration sensor, and the controller is electrically connected with the front online pH sensor array, the rear online pH sensor array, the concentration sensor, the ultrasonic disperser, the dosing device and the stirring mechanism.

2. The apparatus according to claim 1, wherein the apparatus is configured to be used in a reverse osmosis membrane process. The dosing device comprises an alkali agent storage tank, a peristaltic pump and a mixing pipeline, the alkali agent storage tank is communicated with the first end of the mixing pipeline, the peristaltic pump is arranged on the mixing pipeline, and the second end of the mixing pipeline is used for putting alkali agent into raw water.

3. The apparatus of claim 2, wherein the apparatus is configured to be used in a reverse osmosis membrane process. The ultrasonic disperser is adjacent to the second end of the mixing pipeline.

4. The apparatus according to claim 1, wherein the apparatus is a reverse osmosis membrane pre-nucleation inhibitor apparatus. The stirring mechanism comprises a propeller and a variable frequency driver, the propeller is located in the calcium sulfate crystallization reactor, and the variable frequency driver is drivingly connected with the propeller.

5. The apparatus according to claim 1, wherein the apparatus is a reverse osmosis membrane pre-nucleation inhibitor apparatus. A turbidity sensor is further arranged in the calcium sulfate crystallization reactor, and the turbidity sensor is electrically connected with the controller.

6. The apparatus according to claim 1, wherein the apparatus is a reverse osmosis membrane pre-nucleation inhibitor apparatus. The calcium sulfate crystallization reactor is a cylindrical tank, and a spiral heat exchange pipe is arranged on the jacket of the tank, and the spiral heat exchange pipe is communicated with a constant temperature water tank.

7. The apparatus of claim 1, wherein the apparatus is configured to be used in a reverse osmosis membrane process. An inducer inlet is arranged at the top of the calcium sulfate crystallization reactor, and the inducer is a mixture of inert inducer and homogeneous inducer.

8. The apparatus according to claim 1, wherein the apparatus is a reverse osmosis membrane pre-nucleation inhibitor apparatus. The filter further comprises a cyclone separator and a sand filter device, the water inlet of the cyclone separator is communicated with the bottom of the calcium sulfate crystallization reactor, and the outlet of the cyclone separator is communicated with the inlet of the sand filter device.

9. A method for inhibiting crystal nuclei in a reverse osmosis membrane, using the reverse osmosis membrane crystal nuclei inhibiting device according to any one of claims 1 to 8, characterized by, The method comprises the following steps: Start the water inlet pump, and let the raw water flow in, the raw water flows through the front online pH sensor array, the front online pH sensor array measures the pH value of the raw water in real time and sends the data to the controller of the adjusting mechanism; The controller calculates the required amount of alkali agent according to the real-time data of the front online pH sensor array and the target pH value; The dosing device extracts alkali agent from the alkali agent storage tank and injects it into the mixing pipeline; At the dosing point of the mixing pipeline into the raw water, the ultrasonic disperser is started to generate high-frequency vibration to uniformly mix the alkali agent with the raw water; According to the water quality of the raw water, the inducer is selected, the inducer is added into the calcium sulfate crystallization reactor according to the preset concentration, the propeller in the calcium sulfate crystallization reactor is started to make the inducer uniformly distributed in the calcium sulfate crystallization reactor to provide a large number of nucleation sites for the crystallization process; The water flow after pH adjustment and ultrasonic mixing enters the calcium sulfate crystallization reactor, the propeller in the calcium sulfate crystallization reactor is continuously stirred at a variable frequency drive controlled speed, ensuring that the Reynolds number of the water flow in the reactor is always greater than 6000, forming a sufficient turbulent flow state; The water flow passing through the alkali agent adding area passes through the rear online pH sensor array, the rear online pH sensor array measures the adjusted pH value, and feeds back to the controller, the controller compares it with the target value and adjusts the adding rate of the peristaltic pump, forming a pH closed loop control; The concentration sensors installed at the inlet and outlet of the calcium sulfate crystallization reactor monitor the concentration changes of calcium ions and sulfate ions in the water flow, and the controller calculates the saturation index and removal rate of calcium sulfate in real time through data to evaluate the crystallization efficiency.

10. The apparatus according to claim 1, wherein the apparatus is a reverse osmosis membrane pre-nucleation inhibitor apparatus. The controller adjusts the variable frequency drive to change the speed of the propeller according to the real-time data of the turbidity reactor in the calcium sulfate reactor.

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