Natural mineral water pretreatment method and system

Abstract

This invention relates to the field of natural mineral water purification, and in particular to a method and system for pretreatment of natural mineral water. The method includes: saturating the mineral water with aeration; detecting the pH value and manganese ion content of the mineral water after aeration; raising the pH value of the mineral water to a first target pH value based on the pH value and manganese ion content after aeration; performing a secondary manganese removal treatment at the first target pH value; removing iron and manganese precipitates from the mineral water after the secondary manganese removal; and injecting carbon dioxide into the precipitate-removed mineral water to adjust the pH value back to a second target pH value. This invention removes iron and manganese ions through saturated aeration, then further raises the pH value to further accelerate manganese removal. After removing iron and manganese precipitates, the pH value is adjusted back by injecting carbon dioxide. This pH compensation adjustment brings the mineral water back to the normal pH range, facilitating further fine processing.

Description

Technical Field

[0001] This invention relates to the field of natural mineral water purification, and in particular to methods and systems for the pretreatment of natural mineral water. Background Technology

[0002] The pH value of natural mineral water sources varies considerably, ranging from 6.5 to 8.5. Current technologies typically remove oxides such as iron and manganese ions through aeration and manganese sand filtration during the water pretreatment stage. However, this process lacks specificity regarding the pH value of the water source, resulting in the following shortcomings:

[0003] Dissolved ferrous ions oxidize very rapidly at pH 6.0, and aeration is sufficient to largely complete the oxidation. However, manganese is highly pH-dependent, and the oxidation rate of divalent manganese ions is extremely dependent on pH; its oxidation rate only significantly increases when the pH rises to around 8.0. Therefore, for neutral or slightly acidic water sources with a pH of 6.5-7.2, the oxidation conditions provided by a single aeration cycle are far from sufficient to completely oxidize divalent manganese ions. A large amount of unoxidized divalent manganese ions will penetrate the manganese sand filter layer, leading to excessive manganese levels in the effluent, or the unoxidized manganese ions will slowly oxidize in the pipes, forming secondary sedimentation and pipe contamination.

[0004] Furthermore, the pH value of natural water sources can fluctuate with seasons, rainfall, or pumping depth. When the pH of the water source drops (e.g., from 7.5 to 6.8), the system lacks the means to cope, and the manganese removal efficiency decreases sharply. Because the water entering the manganese sand filter still contains a large amount of unoxidized divalent manganese ions, these ions continuously consume the active manganese dioxide oxide layer on the surface of the manganese sand filter media, leading to a rapid decline in the catalytic capacity of the filter media, i.e., "deactivation." More frequent potassium permanganate chemical regeneration is necessary, which not only increases operating costs but also creates additional chemical waste disposal problems. Summary of the Invention

[0005] To address the aforementioned problems, embodiments of this application provide a method for pretreatment of natural mineral water.

[0006] The method includes:

[0007] The mineral water was subjected to saturated aeration treatment.

[0008] The pH value and manganese ion content of the mineral water after aeration treatment were tested.

[0009] Based on the pH value and manganese ion content of the mineral water after aeration treatment, the pH value of the mineral water is raised to the first target pH value, and a second manganese removal treatment is carried out at the first target pH value.

[0010] Remove iron and manganese precipitates from mineral water after secondary manganese removal;

[0011] Carbon dioxide is injected into the mineral water after the sediment has been removed to adjust the pH value, bringing the pH value of the mineral water back to the second target pH value.

[0012] The natural mineral water pretreatment method in this application removes iron and manganese ions through aeration, then further increases the pH value to accelerate manganese removal. After removing iron and manganese precipitates, the pH value is adjusted by injecting carbon dioxide to bring the mineral water back to its optimal taste range. In the pretreatment stage, iron and manganese ions, especially manganese ions, can be repeatedly removed. Moreover, the pH value is adjusted back to the normal pH range through pH compensation, which facilitates further fine processing in the future.

[0013] In one possible implementation, the saturated aeration treatment of the mineral water includes injecting clean air into the mineral water through a spray, waterfall, or bottom-blowing method, so that the oxygen in the clean air is fully dissolved into the mineral water.

[0014] In one possible implementation, the detection of the pH value and manganese ion content of the mineral water after aeration treatment includes obtaining them via an online manganese ion analyzer.

[0015] In one possible implementation, raising the pH of the mineral water to a first target pH value based on the pH value and manganese ion content of the mineral water after aeration treatment includes:

[0016] Based on the pH value of the mineral water after aeration treatment, combined with the first target pH value and manganese ions, the first alkaline auxiliary material dosage value is obtained.

[0017] The acid neutralization consumption value is obtained based on the manganese ion content in the mineral water.

[0018] The second alkaline auxiliary material dosage value is obtained based on the first alkaline auxiliary material dosage value and the acid neutralization consumption value;

[0019] Based on the second alkaline auxiliary material dosage value, control the alkaline auxiliary material dispensing valve to dispense alkaline auxiliary material.

[0020] In one possible implementation, the secondary manganese removal treatment at the first target pH value further includes:

[0021] The feedback pH value is further obtained downstream of the alkaline auxiliary material dispensing valve;

[0022] Based on the feedback pH value and in conjunction with the first target pH value, the dosage of the alkaline auxiliary material is adjusted.

[0023] In one possible implementation, the removal of iron and manganese precipitates from the mineral water after secondary manganese removal includes:

[0024] The mineral water after the secondary manganese removal is controlled to pass through a manganese sand filter tank.

[0025] In one possible implementation, injecting carbon dioxide into the mineral water after removing the precipitate and adjusting the pH value includes:

[0026] Control the water flow inlet of the Venturi mixer into the mineral water after secondary manganese removal;

[0027] A pure, positive-pressure carbon dioxide stream is injected from the throat of the Venturi mixer;

[0028] Mineral water with adjusted pH value is discharged from the water outlet of the Venturi mixer.

[0029] In one possible implementation, the alkaline auxiliary material is a sodium carbonate solution.

[0030] Secondly, embodiments of this application also provide a dynamic pretreatment system for natural mineral water, the system comprising:

[0031] The system includes a control module, a flow meter, a main valve, a first air pump, a second air pump, an auxiliary material dispensing valve, a pH meter, and a filter water valve. The control module controls the main valve to inject mineral water into the aeration tank through the raw water delivery pipe, and obtains the injected water volume through the flow meter. After injection, the main valve is closed, and the first air pump is controlled to inject pure air into the aeration tank for saturated aeration of the mineral water. Then, based on the pH meter reading and a first target pH value, the carbon dioxide injection amount is calculated, and the second air pump is controlled according to the carbon dioxide injection amount. The air pump fills the aeration tank with carbon dioxide and keeps it still to allow the manganese ions to fully react. Then, the control module obtains the pH value and manganese ion content of the treated mineral water through a pH meter and an online manganese ion analyzer. After calculating the amount of alkaline auxiliary material to be added based on the current measurement value of the pH meter, the manganese ion content, and the first target pH value, the control module controls the auxiliary material addition valve to add alkaline auxiliary material to the aeration tank according to the amount of alkaline auxiliary material to be added. After the pH value of the mineral water in the aeration tank drops to the second target pH value, it is injected into the manganese sand filter tank through the filter water valve.

[0032] In one possible implementation, a differential pressure transmitter is also provided at the inlet and outlet of the manganese sand filter tank. The control module acquires the signal from the differential pressure transmitter and performs backflushing of the manganese sand filter tank after the pressure difference between the inlet and outlet of the manganese sand filter tank reaches a threshold. Attached Figure Description

[0033] Figure 1 This is a flowchart illustrating the overall process of the first embodiment of the present invention;

[0034] Figure 2 This is a schematic diagram of the module structure of the second embodiment of the present invention. Detailed Implementation

[0035] The following detailed description, in conjunction with specific embodiments and accompanying drawings, clarifies that the described embodiments are only a portion, not all, of the embodiments. All other embodiments obtained by those skilled in the art based on the following embodiments without inventive effort are also within the scope of protection of this invention.

[0036] It should be understood that if the controllers or control circuits involved in the embodiments are conventional control technologies or units for those skilled in the art, such as the control circuits of the controllers, they can be implemented by those skilled in the art using existing technologies.

[0037] The disclosure of the embodiments provides many different implementations or examples for different ways of implementing the present invention. To simplify the disclosure of the present invention, the embodiments describe components and arrangements of specific examples. Of course, these are merely examples and are not intended to limit the present invention. Furthermore, reference numerals and / or reference letters may be repeated in different examples in the embodiments; such repetition is for simplification and clarity and does not in itself indicate a relationship between the various implementations and / or arrangements discussed. Moreover, if examples of various specific processes and materials are provided in the embodiments, those skilled in the art will recognize the application of other processes and / or the use of other materials.

[0038] To address the aforementioned problems, the first embodiment of this application provides a method for pretreating natural mineral water, comprising the following steps:

[0039] S1. The mineral water is subjected to saturated aeration treatment;

[0040] S2. Test the pH value and manganese ion content of the mineral water after aeration treatment;

[0041] S3. Based on the pH value and manganese ion content of the mineral water after aeration treatment, raise the pH value of the mineral water to the first target pH value, and perform a second manganese removal treatment at the first target pH value;

[0042] S4. Remove iron and manganese precipitates from mineral water after secondary manganese removal;

[0043] S5. Inject carbon dioxide into the mineral water after removing the sediment to adjust the pH value and bring the pH value of the mineral water back to the second target pH value.

[0044] In step S1, the core function of aeration is to introduce dissolved oxygen (DO) into the raw water, triggering a series of physical and chemical / biochemical reactions. Natural mineral water generally contains dissolved ferrous ions. Divalent manganese ions The presence of these ions can cause water to become cloudy and have a metallic taste, and they can also settle and clog pipes. Aeration increases the dissolved oxygen content in the water, thus removing dissolved ions. and It is oxidized into a higher valence compound that is insoluble in water, among which,

[0045] The reaction process for removing iron ions is as follows:

[0046]

[0047] The reaction process for removing manganese ions is as follows:

[0048]

[0049] Subsequently, the iron hydroxide precipitate (reddish-brown) and manganese dioxide precipitate (dark brown) generated by the reaction are suspended solids and can be removed through subsequent filtration steps, such as manganese sand filtration or multi-media filtration.

[0050] Meanwhile, the aeration process also removes dissolved hydrogen sulfide, carbon dioxide, and other substances from the water, improving its taste and odor. Furthermore, removing some carbon dioxide can slightly increase the pH level of the water, which is beneficial for subsequent oxidation reactions.

[0051] The types of aeration processes and the main equipment used in the aeration process are as follows:

[0052] 1. Cascading aeration device: using multi-layer perforated trays, aeration towers, or cascading basins, raw water falls from a height or flows downward through multi-layer perforated plates, forming a water film or droplets that come into full contact with the air, thereby increasing oxygen.

[0053] 2. The aeration device uses a blower / air compressor and an air diffuser. The blower sends compressed air into the water from the bottom of the pool, and the diffuser forms tiny bubbles. As the bubbles rise, oxygen dissolves into the water.

[0054] 3. Jet / jet aeration device: using a water pump, venturi nozzle or nozzle, high-speed water flow through the nozzle or jet generator to create negative pressure, draw air into the water, form an air-water mixture, and then disperse it into the water body.

[0055] Each process also requires auxiliary equipment as a reaction vessel, such as a raw water tank / aeration tank, to provide aeration reaction space and necessary residence time, and to serve as a buffer for subsequent filtration.

[0056] The aeration treatment of mineral water uses physical aeration, which requires control of dissolved oxygen content and reaction residence time. The dissolved oxygen (DO) content needs to be controlled within a reasonable range, usually above 4-6 mg / L, to ensure that the iron and manganese oxidation reaction is rapid and complete. Excessive aeration may lead to excessive removal of carbon dioxide, causing the water pH to be too high, affecting the taste; or it may cause water temperature fluctuations.

[0057] Reaction retention time (HRT) is the time that aerated water needs to remain in the environment, typically from a few minutes to several hours, to ensure that iron and manganese ions have sufficient time to be oxidized and form filterable precipitates.

[0058] However, based on the multiple pH adjustment steps and subsequent pH reset steps in this embodiment, saturated aeration is used during the aeration process. This means that carbon dioxide is thoroughly removed from the mineral water during the aeration stage, and saturated dissolved oxygen (8-12 mg / L) is introduced during aeration, resulting in a dissolved oxygen content of 9-9.2 mg / L under normal temperature and pressure conditions. Under these conditions, the pH reaches a relatively high level compared to natural conditions. Since the oxidation of iron ions can be completed relatively quickly at a pH greater than 6, while the oxidation of manganese ions only shows significant acceleration at a pH greater than or equal to 8, saturated aeration can effectively oxidize iron ions and partially oxidize manganese ions.

[0059] Since this process is in the pretreatment stage of mineral water, there is no need to consider the impact of pH increase on taste at this time.

[0060] In addition, the air used for aeration must be clean air, which needs to be dust-removed and filtered to prevent pollutants such as dust, microorganisms, and oil from being brought into the mineral water.

[0061] At this point, the pH value of the aerated mineral water is usually between 7.2 and 7.5. Iron ions are basically oxidized, but manganese ions have not yet reached the optimal pH value for oxidation. Moreover, the oxidation of iron ions releases hydrogen ions, further lowering the pH value, which is not conducive to the oxidation of manganese ions. In order to fully treat the oxidation of manganese ions, the pH value raised by aeration alone cannot meet the reaction requirements. Therefore, it is necessary to actively intervene to artificially raise the pH value, such as by adding alkaline auxiliary materials. In order to determine the amount of alkaline auxiliary materials to be added, in this embodiment, step S2 detects the pH value and manganese ion content of the mineral water after aeration. After the saturated aeration treatment in step S1, plus the reaction residence time in this process, the treated mineral water obtains a stable pH value benchmark. At this point, step S2 can obtain an accurate pH value by detecting the pH value. At the same time, considering that hydrogen ions will be released in the subsequent reaction of manganese ions, the pH value will decrease accordingly. Therefore, it is also necessary to measure the manganese ion content to control the overall dosage of alkaline auxiliary materials.

[0062] pH measurement is a common testing method and will not be discussed further here. Manganese ion measurement can be obtained through an online manganese ion analyzer.

[0063] After detecting the pH value and manganese ion content of the water in step S2, step S3 raises the pH value of the mineral water to the first target pH value based on the pH value and manganese ion content of the mineral water after aeration treatment, and performs secondary manganese removal treatment at the first target pH value.

[0064] The first target pH value is the pH value of an environment that provides sufficient oxidation for manganese ions; in this embodiment, it is set to 8.5. Using the first target pH value, combined with the water pH value measured in step S2, and considering the hydrogen ions released during the oxidation reaction based on the manganese ion content, the required amount of alkaline auxiliary material can be calculated. In step S3, the calculated amount of alkaline auxiliary material is added to the mineral water to raise the water pH value to the first target pH value. Through a certain reaction residence time, the manganese ions can be fully oxidized and removed. During this process, unreacted iron ions can continue to undergo oxidation.

[0065] After the above steps, the iron and manganese ions are fully oxidized. The iron hydroxide and manganese dioxide generated in the water are present in the water as suspended matter and precipitate. In order to facilitate further purification, step S4 removes the iron and manganese precipitate in the mineral water after the second manganese removal.

[0066] In this embodiment, the alkaline auxiliary material is a food-grade sodium carbonate solution. Sodium carbonate has moderate alkalinity and excellent water buffering capacity, which is well-suited to the scenario of hydrogen ion generation during manganese oxidation. It can reduce pH fluctuations and make pH control and fine-tuning easier.

[0067] The water treated in step S3 enters the manganese sand filter tank, where the filtration process begins. The manganese sand filter tank has a dual key function in this process: Sediment Retention: It physically removes existing ferric precipitates and small amounts of oxidized tetravalent manganese precipitates from the water. Catalytic Fine Filtration (Secondary Manganese Removal): Under optimal oxidation conditions after the pH value is raised to the first target pH value, the manganese dioxide active layer on the surface of the manganese sand acts as a highly efficient catalyst, rapidly oxidizing and adsorbing residual divalent manganese ions in the water flow.

[0068] The fluid and chemical behavior of the filtration process: Water enters from the top of the filter tank and permeates evenly downwards through the filter media layer. This layer consists of quartz sand and manganese sand of varying particle sizes, forming a highly porous structure. Larger particles in the water are initially physically intercepted by the surface and pores of the filter media. As the water flows deeper into the filter layer, finer colloidal precipitates are captured by the filter media surface through Brownian motion, van der Waals forces, and adsorption. Simultaneously, the primary target pH provides a strong impetus for the oxidation of manganese ions. When the water flows over the surface of the catalytically active manganese sand particles, unoxidized manganese ions are rapidly catalytically oxidized and adhere to the manganese sand surface in the form of manganese dioxide.

[0069] Since the manganese ions have been sufficiently oxidized in step S3 in this embodiment, the filtration process is mainly physical filtration, which greatly reduces the oxidative catalytic effect of manganese sand particles on unoxidized manganese ions. This allows the chemical properties of the manganese sand to be maintained for a longer period of time, reduces the requirement for subsequent regeneration of the manganese sand, and extends the regeneration cycle.

[0070] Key features of filter canister structure and technology: Layered filter media: Filter canisters typically employ multiple layers of filter media. The upper layer may consist of coarser-grained quartz sand or anthracite to trap most of the coarse particles; the lower layer is made of finer-grained, catalytically active manganese sand for fine filtration and catalytic oxidation. This layered structure ensures maximum filtration capacity and dirt-holding capacity.

[0071] It is important to note that when controlling the water flow through the manganese sand filter tank, the flow rate through the filter layer must be strictly controlled. Excessive flow rate will cause the water to push sediment through the filter layer, affecting the quality of the effluent. After treatment by this filter tank, the iron and manganese concentrations in the water must consistently meet the national standards for natural drinking mineral water, and the turbidity of the effluent will also be significantly reduced.

[0072] As operating time increases, the trapped sediment gradually accumulates, leading to an increase in the water pressure difference between the inlet and outlet of the filter tank. When the pressure difference reaches a preset threshold, the system must initiate a backwashing procedure. A high-flow-rate water or aeration water system is used to flush the filter media layer from bottom to top, stripping away the trapped iron and manganese precipitates and discharging them into the wastewater treatment system, restoring the filter media's filtration capacity. For manganese sand, periodic chemical regeneration with potassium permanganate solution is necessary to restore its surface catalytic activity and ensure long-term stable manganese removal performance.

[0073] S5. Inject carbon dioxide into the mineral water after removing the sediment to adjust the pH value and bring the pH value of the mineral water back to the second target pH value.

[0074] pH adjustment is an important finishing step in this embodiment, which achieves triple optimization of process safety, product taste, and subsequent sterilization efficiency.

[0075] To achieve efficient manganese removal in the preceding process, the water's pH level is raised to a highly alkaline range of 7.8 to 8.2. Water with a high pH (strongly or weakly alkaline) typically tastes astringent or alkaline, lacking the crispness characteristic of natural mineral water. The injection of carbon dioxide during the return process generates carbonic acid, causing a moderate decrease in pH and significantly improving the product's drinkability.

[0076] Furthermore, the final step in mineral water treatment is sterilization, typically using a combination of ozone and ultraviolet light. The rate of bromate formation from ozone is positively correlated with pH. The higher the pH, the higher the risk of bromate. If the pH is not adjusted and ozone sterilization is performed at around pH 8.0, bromate levels are very likely to exceed the limit. Lowering the pH back to neutral or slightly alkaline can exponentially reduce the rate of bromate formation. This creates a safety window for subsequent low-dose ozone sterilization, achieving the core premise of "dynamically avoiding bromate risks."

[0077] Impact of subsequent fine filtration on stability: Although manganese sand filtration is complete, extremely low concentrations of residual iron and manganese may undergo slight chemical changes when the pH value changes drastically. pH adjustment effect: After pH adjustment, the water body enters a stable state, ensuring the final stability of the water quality and preventing any trace sediment from precipitating in the pipeline before the final packaging stage.

[0078] The optimal target range for pH adjustment is determined based on a comprehensive consideration of taste, safety, and national standards. In this embodiment, the target pH range is 7.2-7.6.

[0079] The following are the principles of acid-base regulation during the two processes of adjusting the pH value of the water.

[0080] Adding sodium carbonate to water Subsequently, a carbonate buffer system is formed, which makes precise pH adjustment possible. When sodium carbonate is added during the alkalinity enhancement phase, the following equilibrium relationships mainly exist in the water:

[0081]

[0082] carbonate It is a strong base that raises the pH to 8.2-8.5. At this point, the main buffer pair in the water is bicarbonate. carbonate Ion pairs. (This is achieved through the injection of carbon dioxide.) During the callback phase, the acidic substance is buffered. When injected... When it is in gaseous form, it dissolves in water to form carbonic acid:

[0083]

[0084]

[0085] The generated hydrogen ions It will not directly cause a sharp drop in pH value; rather, it will first be affected by the large amount of alkaline carbonate ions in the system. Buffer it:

[0086]

[0087] Inject carbon dioxide In fact, it is the alkaline carbonate ion Gradually transforms into neutral bicarbonate ions This is achieved by injecting baking soda, which gently and gradually lowers the pH of the water. This buffering effect makes the pH decrease very smooth and controllable. This can be precisely achieved by injecting carbon dioxide. The flow rate is used to control the final stable pH value.

[0088] The second embodiment of the present invention provides a dynamic pretreatment system for natural mineral water. The system includes a raw water delivery pipe, an aeration tank, and a manganese sand filter tank connected in sequence. The raw water delivery pipe is equipped with a flow meter 2 and a main valve 3. The aeration tank is connected to a pure air pipeline, a carbon dioxide pipeline, and an alkaline auxiliary material pipeline. The pure air pipeline is equipped with a first air pump 4, the carbon dioxide pipeline is equipped with a second air pump 5, the alkaline auxiliary material pipeline is equipped with an auxiliary material dispensing valve 6, and the inlet of the manganese sand filter tank is equipped with a water filtration valve 7. The aeration tank is equipped with a pH meter 8 and an online manganese ion analyzer 9. The flow meter 2, the main valve 3, the first air pump 4, the second air pump 5, and the pH meter 8 are connected to a control module 1.

[0089] The control module controls the main valve to inject mineral water into the aeration tank through the raw water delivery pipe, and obtains the injected water volume through a flow meter. After injection, the main valve is closed, and the first air pump is controlled to inject pure air into the aeration tank for saturated aeration treatment of the mineral water. Then, the carbon dioxide charging amount is calculated based on the measurement value of the pH meter and the first target pH value. Based on the carbon dioxide charging amount, the second air pump is controlled to charge carbon dioxide into the aeration tank and keep it static to wait for the manganese ions to fully react. Then, the control module obtains the pH value and manganese ion content of the treated mineral water through the pH meter and the online manganese ion analyzer, respectively. After calculating the amount of alkaline auxiliary material to be added based on the current measurement value of the pH meter, the manganese ion content and the first target pH value, the control module controls the auxiliary material addition valve to add alkaline auxiliary material into the aeration tank according to the amount of alkaline auxiliary material to be added, so that the pH value of the mineral water in the aeration tank drops to the second target pH value, and then it is injected into the manganese sand filter tank through the filter water valve.

[0090] The manganese sand filter tank is also equipped with a differential pressure transmitter 10 at the inlet and outlet. The control module acquires the differential pressure transmitter signal and executes the backwashing of the manganese sand filter tank after the pressure difference between the inlet and outlet of the manganese sand filter tank reaches the threshold.

[0091] The above description is merely a preferred embodiment of the present application and does not limit the scope of disclosure of the embodiments of the present application. Any equivalent structural or procedural transformations made using the description and drawings of the embodiments of the present application, or direct or indirect applications in other related technical fields, are similarly included within the scope of patent protection supported by the embodiments of the present application.

Claims

1. A method for pretreatment of natural mineral water, characterized in that, include: The mineral water was subjected to saturated aeration treatment. The pH value and manganese ion content of the mineral water after aeration treatment were tested. Based on the pH value and manganese ion content of the mineral water after aeration treatment, the pH value of the mineral water is raised to the first target pH value, and a second manganese removal treatment is carried out at the first target pH value. Remove iron and manganese precipitates from mineral water after secondary manganese removal; Carbon dioxide is injected into the mineral water after the sediment has been removed to adjust the pH value and bring the pH value of the mineral water back to the second target pH value. The step of raising the pH value of the mineral water to a first target pH value based on the pH value and manganese ion content of the mineral water after aeration treatment includes: Based on the pH value of the aerated mineral water and the first target pH value, the first alkaline auxiliary material dosage value is obtained. The acid neutralization consumption value is obtained based on the manganese ion content and the mineral water volume. The second alkaline auxiliary material dosage value is obtained based on the first alkaline auxiliary material dosage value and the acid neutralization consumption value; Based on the second alkaline auxiliary material dosage value, control the alkaline auxiliary material dispensing valve to dispense alkaline auxiliary material.

2. The natural mineral water pretreatment method as described in claim 1, characterized in that, The saturated aeration treatment of mineral water includes injecting clean air into the mineral water through spraying, waterfall, or bottom-blowing methods, so that the oxygen in the clean air can be fully dissolved into the mineral water.

3. The natural mineral water pretreatment method as described in claim 1, characterized in that, The manganese ion content was obtained using an online manganese ion analyzer.

4. The natural mineral water pretreatment method as described in claim 1, characterized in that, The secondary manganese removal treatment at the first target pH value also includes: The feedback pH value is further obtained downstream of the alkaline auxiliary material dispensing valve; Based on the feedback pH value and in conjunction with the first target pH value, the dosage of the alkaline auxiliary material is adjusted.

5. The natural mineral water pretreatment method as described in claim 1, characterized in that, The removal of iron and manganese precipitates from the mineral water after secondary manganese removal includes: The mineral water after the secondary manganese removal is controlled to pass through a manganese sand filter tank.

6. The method for pretreatment of natural mineral water as described in claim 1, characterized in that, The step of injecting carbon dioxide into the mineral water after removing precipitates to adjust the pH value includes: Control the water flow inlet of the Venturi mixer into the mineral water after secondary manganese removal; A pure, positive-pressure carbon dioxide stream is injected from the throat of the Venturi mixer; Mineral water with adjusted pH value is discharged from the water outlet of the Venturi mixer.

7. The natural mineral water pretreatment method as described in claim 4, characterized in that, The alkaline auxiliary material is a sodium carbonate solution.

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