Ultrapure water preparation system adopting oxidation-reduction potential monitoring method

Abstract

The utility model relates to the technical field of ultrapure water preparation, in particular to an ultrapure water preparation system adopting a redox potential monitoring method, which comprises a pretreatment module, a primary reverse osmosis module, a PH regulator, a secondary reverse osmosis module, a pure water tank, a polishing resin mixed bed, precision sintering activated carbon, an ultraviolet sterilizer and an ultrapure water output module which are connected in sequence, an ultraviolet power density monitor is arranged on one side of the ultraviolet sterilizer, a sampler for sampling ultrapure water is arranged on one side of the ultrapure water output module, and an oxidation-reduction potential monitor and a megohm resistance meter are arranged in the sampler. According to the utility model, water molecules are activated by utilizing reverse osmosis separation and shearing effects, and high-energy medium-pressure ultraviolet irradiation is utilized, so that the high oxidation potential state of ultrapure water is further excited and maintained, and the ultrapure water is ensured to meet the high-standard requirements of special industries such as chip production, physical and chemical exploration, high-precision cleaning and the like.

Description

Technical Field

[0001] This utility model relates to the field of ultrapure water production technology, specifically to an ultrapure water production system based on oxidation-reduction potential monitoring. Background Technology

[0002] Ultrapure water typically refers to water produced through distillation, deionization, reverse osmosis, or other more advanced supercritical fine technologies, with a resistivity extremely close to the limit of 18.3 MΩ·cm. With the rapid development of modern science and technology and industry, the demand for ultrapure water from various industries has increased dramatically not only in quantity but also in quality, with increasingly stringent requirements.

[0003] In many application fields, such as bioscience, pharmaceutical manufacturing, and automotive manufacturing, ultrapure water mainly plays the roles of solvent, cleaning fluid, or reaction medium. For these fields, ensuring that ultrapure water meets certain purity standards is crucial, as even trace amounts of impurities can have a significant impact on experimental results, product quality, or production processes. In practice, we usually use resistivity as an indicator to characterize the purity of ultrapure water. The higher the resistivity, the lower the ion content in the water, and the higher the purity. In most applications, a resistivity of 13–18.2 MΩ·cm is sufficient to meet the requirements.

[0004] However, in specific fields such as chip manufacturing, physical and chemical research, and precision cleaning, the role of ultrapure water is more complex and critical. These fields not only require ultrapure water to have extremely high purity, but also stronger permeability, dissolving power, and etching and passivation capabilities. While traditional resistivity indicators can reflect the ion content in water, they cannot fully reflect these special properties of ultrapure water, and cannot accurately determine whether ultrapure water is suitable for specific fields such as chip manufacturing, physical and chemical research, and precision cleaning.

[0005] Currently, most widely used ultrapure water preparation systems still rely solely on resistivity as the only or primary indicator in the preparation process. While this approach may barely meet the needs in some general scenarios, it falls short when facing the high standards and stringent requirements of the aforementioned specific fields for ultrapure water. The ultrapure water produced is often unable to fully meet the usage requirements of these fields, thus hindering the development and progress of related industries to some extent. Utility Model Content

[0006] To address the shortcomings of existing technologies, this invention provides an ultrapure water production system based on oxidation-reduction potential monitoring.

[0007] To achieve the above objectives, the technical solution of this utility model is as follows: an ultrapure water production system using oxidation-reduction potential monitoring, comprising a pretreatment module, a first-stage reverse osmosis module, a pH regulator, a second-stage reverse osmosis module, a pure water tank, a polishing resin mixed bed, precision sintered activated carbon, an ultraviolet sterilizer, and an ultrapure water output module connected in sequence; an ultraviolet power density monitor is installed on one side of the ultraviolet sterilizer, and a sampler for collecting ultrapure water is installed on one side of the ultrapure water output module, wherein an oxidation-reduction potential monitor and a megohmmeter are installed inside the sampler.

[0008] Furthermore, a booster pump is provided between the pretreatment module and the first-stage reverse osmosis module.

[0009] Furthermore, a secondary booster pump is provided between the pH regulator and the secondary reverse osmosis module.

[0010] Furthermore, a pure water pump is provided between the pure water tank and the polishing resin mixing bed.

[0011] Furthermore, the ultraviolet sterilizer is a medium-pressure ultraviolet sterilizer.

[0012] Furthermore, the wavelength of the ultraviolet light in the ultraviolet sterilizer is 200–400 nanometers, and the energy density is not less than 1500 mW / cm². 2 .

[0013] Furthermore, the working electrode in the redox potential monitor is pure gold, and the reference electrode is a silver-silver chloride saturated potassium chloride solution.

[0014] The beneficial effects achieved by this utility model are as follows:

[0015] 1. This utility model uses two-stage reverse osmosis, precision sintered activated carbon, and medium-pressure ultraviolet irradiation as its core basic processes. It is equipped with pretreatment and post-treatment processes. It utilizes reverse osmosis separation and shearing to activate water molecules, and high-energy medium-pressure ultraviolet irradiation to further stimulate and maintain the high oxidation potential state of ultrapure water, thereby enhancing the permeability, solubility, and etching passivation ability of ultrapure water. It is particularly suitable for specific fields such as chip manufacturing, physical and chemical research, and precision cleaning.

[0016] 2. This utility model can monitor the quality and oxidation potential of ultrapure water in real time by setting up an oxidation-reduction potential monitor and a megohmmeter to ensure that the water quality fully meets the standards. At the same time, based on the monitoring results, the system can provide timely feedback and take corresponding measures, such as increasing the ultraviolet power or replacing the reverse osmosis membrane, to ensure the continuous high-quality output of ultrapure water.

[0017] 3. This utility model adopts pretreatment technology and dual-stage reverse osmosis technology, which effectively extends the service life of the reverse osmosis membrane, reduces the replacement frequency and cost, and the use of medium-pressure ultraviolet sterilizer also reduces the amount of chemical disinfectant used, further reducing maintenance costs and environmental burden. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the overall structure of this utility model.

[0019] The markings in the diagram are as follows: 1. Pretreatment module; 2. First-stage booster pump; 3. First-stage reverse osmosis module; 4. pH regulator; 5. Pure water pump; 6. Pure water tank; 7. Second-stage reverse osmosis module; 8. Second-stage booster pump; 9. Polishing resin mixed bed; 10. Precision sintered activated carbon; 11. Ultraviolet sterilizer; 12. Ultrapure water output module. Detailed Implementation

[0020] To better understand the purpose, structure, and function of this utility model, the following description, in conjunction with the accompanying drawings, provides a more detailed account of an ultrapure water production system based on oxidation-reduction potential monitoring.

[0021] like Figure 1 As shown, an ultrapure water production system using oxidation-reduction potential monitoring includes a pretreatment module 1, a primary reverse osmosis module 3, a pH regulator 4, a secondary reverse osmosis module 7, a pure water tank 6, a polishing resin mixed bed 9, a precision sintered activated carbon 10, an ultraviolet sterilizer 11, and an ultrapure water output module 12, connected in sequence.

[0022] Pretreatment module 1 includes a raw water booster pump, a quartz sand filter, an activated carbon filter, a water softener, and a fine filter connected in sequence. The pressure applied to the raw water by the raw water booster pump is greater than the total flow resistance of the subsequent quartz sand filter, activated carbon filter, water softener, and fine filter. The quartz sand filter uses filter media of different particle sizes (such as quartz sand and anthracite) for physical filtration, effectively removing larger particles such as suspended solids and silt from the water, preventing clogging of the reverse osmosis membrane elements in the subsequent reverse osmosis module. The activated carbon filter removes odors, residual chlorine, and some organic pollutants from the water through the adsorption of activated carbon. The water softener removes calcium from the water... 2+ Mg 2+ Cations and Na in the exchanger +Ion exchange reduces water hardness, softening the water and preventing scaling in subsequent equipment. The fine filter, located upstream of the first-stage reverse osmosis module 3, is the final filtration device before the raw water enters the membrane elements. It removes substances not completely removed by the quartz sand filter and activated carbon filter, such as suspended solids larger than 5 microns, non-straight particles, and colloids. It also traps lost sand fragments and activated carbon powder, thus protecting the membrane elements in the subsequent reverse osmosis modules from fouling. The pretreatment module 1 effectively removes suspended solids, silt, organic matter, residual chlorine, and other impurities from the water through physical filtration and adsorption. This reduces clogging and fouling of the membrane elements in the subsequent reverse osmosis modules, extends the lifespan of the reverse osmosis membranes, and lowers equipment maintenance costs.

[0023] A primary booster pump 2 is installed between the primary reverse osmosis module 3 and the pretreatment module 1. The primary booster pump 2 overcomes the resistance of the reverse osmosis membrane within the primary reverse osmosis module 3 and maintains the required operating pressure of the system. The primary reverse osmosis module 3 is mainly used for the initial removal of dissolved salts, colloids, organic matter, and some inorganic salts from the water. The pressurization by the primary booster pump 2 forces high-pressure water through a semi-permeable membrane, allowing water molecules to pass through while most impurities are retained, laying a solid foundation for subsequent advanced treatment.

[0024] pH regulator 4 is used to adjust and monitor the pH value of the water flowing out of the first-stage reverse osmosis module 3.

[0025] A secondary booster pump 8 is installed between the pH regulator 4 and the secondary reverse osmosis module 7. The secondary booster pump 8 is used to overcome the resistance of the reverse osmosis membrane in the secondary reverse osmosis module 7 to water. The pore size of the reverse osmosis membrane in the secondary reverse osmosis module 7 is smaller than that of the reverse osmosis membrane in the primary reverse osmosis module 3. Through a finer filtration and desalination process, the secondary reverse osmosis module 7 can further remove trace dissolved salts, heavy metal ions and organic pollutants from the water, ensuring that the effluent reaches a higher purity standard.

[0026] The pure water tank 6 is used to store pure water treated by the secondary reverse osmosis module 7 for subsequent use. Simultaneously, the pure water tank 6 also helps balance the water pressure and volume within the system. A pure water pump 5 is installed between the pure water tank 6 and the polishing resin mixing bed 9, and the pure water pump 5 is used to transport the pure water in the pure water tank 6 to the polishing resin mixing bed 9 for further purification.

[0027] The polishing resin mixed bed 9 further removes ions and dissolved substances from the water, ensuring water purity, thereby increasing the resistivity of the effluent and reducing the total organic carbon (TOC) content in the water.

[0028] The ultraviolet sterilizer 11 is preferably a medium-pressure ultraviolet sterilizer, wherein the wavelength of the ultraviolet light in the ultraviolet sterilizer 11 is 200-400 nanometers, and the energy density is not less than 1500 milliwatts per square centimeter (mW / cm²). 2The medium-pressure ultraviolet (UV) sterilizer uses high-intensity UV light generated by medium-pressure UV lamps to destroy the DNA or RNA structure of microorganisms, thereby rendering them unable to reproduce and achieving disinfection. Simultaneously, the UV sterilizer activates the water quality and maintains it at a high oxidation potential, meeting the needs of specific fields such as chip manufacturing, physicochemical research, and precision cleaning. To ensure the continuous and effective operation of the UV sterilizer 11, a UV power density monitor is installed on one side. This monitor can track the UV energy density within the UV sterilizer 11 in real time. When the monitoring results show that the medium-pressure UV energy density is lower than a preset threshold (less than 1500 mW / cm²), it is necessary to replace the UV lamps in the medium-pressure UV sterilizer to maintain the medium-pressure UV energy density above 1500 mW / cm², thereby maintaining the oxidation-reduction potential of the ultrapure water above 600 mV.

[0029] A sampler for collecting ultrapure water is installed on one side of the ultrapure water output module 12. The sampler is independent of the ultrapure water output module 12 and uses a flow-through sampling method. The sampled ultrapure water does not flow back to the ultrapure water output module 12. The sampler contains an oxidation-reduction potential monitor for measuring the oxidation-reduction potential of ultrapure water and a megohmmeter for measuring its resistivity. The working electrode of the oxidation-reduction potential monitor is pure gold, and the reference electrode is a silver-silver chloride saturated potassium chloride solution.

[0030] When using this invention to produce ultrapure water, the oxidation-reduction potential monitor and megohmmeter monitor the quality of the ultrapure water in real time, ensuring that the resistivity of the produced ultrapure water is not less than 18 MΩ·CM, while the oxidation-reduction potential also meets the production requirements, so as to ensure that the water quality fully meets the standards.

[0031] Typically, a two-hour monitoring period is set to observe changes in the oxidation potential of ultrapure water. When the oxidation potential of ultrapure water remains below 470MV, the staff first enhances the water treatment process by increasing the UV power in the medium-pressure UV sterilizer to raise the oxidation-reduction potential of the produced water to above 600MV. If increasing the power of the medium-pressure UV light still fails to effectively raise the oxidation potential of the ultrapure water, the reverse osmosis membrane in the first-stage reverse osmosis module 3 needs to be replaced. If the monitoring results show that the oxidation potential of ultrapure water remains below 350MV for two hours, the reverse osmosis membrane in the second-stage reverse osmosis module 7 should be replaced. If the UV power density monitor detects that the UV energy density in the medium-pressure UV sterilizer is less than 1500 milliwatts per square centimeter, the decrease in energy density means that the sterilization and oxidation capabilities of the medium-pressure UV light have weakened and can no longer meet the water treatment requirements. In this case, the medium-pressure UV sterilizer needs to be replaced to maintain the medium-pressure UV energy density above 1500 milliwatts per square centimeter, thereby maintaining the oxidation-reduction potential of the ultrapure water above 600MV.

[0032] Table 1. Measurement data of ultrapure water produced by this invention over 2 hours.

[0033] Temperature ℃ 10 15 20 25 30 35 Oxidation potential MV 645 639.5 634.5 630 626 622.5 Resistivity (MΩ.CM) 18.29 18.27 18.26 18.25 18.22 18.16

[0034] It is understood that this utility model has been described through some embodiments, and those skilled in the art will recognize that various changes or equivalent substitutions can be made to these features and embodiments without departing from the spirit and scope of this utility model. Furthermore, under the teachings of this utility model, these features and embodiments can be modified to adapt to specific situations and materials without departing from the spirit and scope of this utility model. Therefore, this utility model is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are within the protection scope of this utility model.

Claims

1. A redox potential monitoring method for producing ultrapure water, characterized in that: The system includes a pretreatment module (1), a first-stage reverse osmosis module (3), a pH regulator (4), a second-stage reverse osmosis module (7), a pure water tank (6), a polishing resin mixed bed (9), precision sintered activated carbon (10), an ultraviolet sterilizer (11), and an ultrapure water output module (12) connected in sequence. An ultraviolet power density monitor is provided on one side of the ultraviolet sterilizer (11), and a sampler for taking ultrapure water is provided on one side of the ultrapure water output module (12). The sampler is equipped with an oxidation-reduction potential monitor and a megohmmeter.

2. The ultrapure water production system using redox potential monitoring according to claim 1, characterized in that: A primary booster pump (2) is provided between the pretreatment module (1) and the primary reverse osmosis module (3).

3. The ultrapure water production system using redox potential monitoring according to claim 1, characterized in that: A secondary booster pump (8) is provided between the pH regulator (4) and the secondary reverse osmosis module (7).

4. The ultrapure water production system using redox potential monitoring according to claim 1, characterized in that: A pure water pump (5) is provided between the pure water tank (6) and the polishing resin mixing bed (9).

5. The ultrapure water production system using redox potential monitoring according to claim 1, characterized in that: The ultraviolet sterilizer (11) is a medium-pressure ultraviolet sterilizer.

6. The ultrapure water production system using redox potential monitoring according to claim 1, characterized in that: The ultraviolet light in the ultraviolet sterilizer (11) has a wavelength of 200-400 nanometers and an energy density of not less than 1500 mW / cm². 2 .

7. The ultrapure water production system using redox potential monitoring according to claim 1, characterized in that: The working electrode of the redox potential monitor is pure gold, and the reference electrode is a silver-silver chloride saturated potassium chloride solution.

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