A filter element for simulating alpine groundwater quality drinking water, and a preparation method and water purification device thereof

Abstract

The application discloses a filter core for simulating drinking water of Alps underground water quality, a preparation method of the filter core and a water purification device. According to mass fractions, the filter core comprises 90-110 parts of modified limestone, 45-55 parts of modified granite, 225-275 parts of modified ultramafic rock, 405-495 parts of activated carbon and 405-495 parts of a binder. Filtered water of the filter core meets the characteristics of Alps underground water quality, is beneficial to human health and achieves the purpose of healthy drinking water. The preparation method of the filter core has the advantages of simple process and large-scale industrial production. The filter core provided by the application or the filter core prepared by the preparation method of the filter core is matched with the water purification device, and drinking water of Alps underground water quality can be obtained.

Description

Technical Field

[0001] This application relates to the field of water purification technology, and in particular to a filter element for drinking water that simulates the quality of groundwater in the Alps, its preparation method, and a water purification device. Background Technology

[0002] Drinking water is an essential commodity for human life, and its quality is closely related to human health, having a far-reaching impact on human survival and development. Therefore, drinking water quality is a major public concern and a hot research topic. Many residents use household water purifiers to address the safety and health issues of their drinking water. However, over 90% of the water purifiers currently on the market are RO reverse osmosis water purifiers, which filter out almost all contaminants and solve the safety problem, but because pure water lacks minerals, it cannot solve the health problems associated with drinking water.

[0003] Taking packaged drinking water as an example, packaged drinking water includes purified water, mineral water, and spring water. Spring water is the most expensive, but it is also the richest in minerals and considered the healthiest water. The Cachart spring in Evian, France, is located in the central Alps. The region's geological lithology is characterized by granite as a base, overlain by alkaline volcanic rocks, ultramafic rocks, carbonate rocks, and sandstone sedimentary rocks. Through continuous seepage through these rock layers, a spring rich in various minerals and trace elements has been formed. This spring water is characterized by high mineralization, high calcium and magnesium content, metasilicic acid content, and strontium richness, making it a healthy drinking water source.

[0004] Achieving drinking water quality comparable to Alpine mineral water is of great significance to drinking water health. Mineralization technology is an important means to achieve this quality. Therefore, the technical problem to be solved in this application is how to provide a filter element for drinking water that simulates the quality of Alpine groundwater. Summary of the Invention

[0005] In view of this, this application provides a filter element for drinking water that simulates the quality of groundwater in the Alps, as well as a method for preparing the filter element and a water purification device, so that the drinking water can reach the quality of Alpine mineral water.

[0006] The technical solution of this application is as follows:

[0007] In a first aspect, this application provides a filter element for drinking water that simulates the groundwater quality of the Alps. The filter element comprises, by weight parts: 90 to 110 parts of modified limestone, 45 to 55 parts of modified granite, 225 to 275 parts of modified ultramafic rock, 405 to 495 parts of activated carbon, and 405 to 495 parts of binder.

[0008] Optionally, the modified granite is obtained by modifying natural granite from the Alpine mineral water source; a modified granite of equivalent mass to that in the filter element is placed in 500 mL of pure water at a temperature of 20℃~30℃ and soaked for 24 h to obtain a modified granite soaking solution; in the modified granite soaking solution, the aluminum content is less than 0.03 mg / L;

[0009] And / or, the modified ultramafic rock is obtained by modifying natural ultramafic rock originating from the Alpine mineral water source; a modified ultramafic rock of equivalent mass to that in the filter element is placed in 500 mL of pure water at a temperature of 20℃~30℃ and soaked for 24 h to obtain a modified ultramafic rock soaking solution; in the modified ultramafic rock soaking solution, the aluminum content is less than 0.03 mg / L, the manganese content is less than 0.03 mg / L, and the iron content is less than 0.05 mg / mL;

[0010] And / or, the modified limestone is obtained by modifying natural limestone originating from the Alpine mineral water production area; the modified limestone, the activated carbon and the binder of equivalent mass to those in the filter element are used to prepare a composite mineralized carbon rod, and the composite mineralized carbon rod is then assembled into a test filter element, wherein the calcium content in the filtered water of the test filter element is 73 mg / L to 78 mg / L.

[0011] Optionally, the activated carbon is acid-washed coconut shell activated carbon, and / or the binder is ultra-high molecular weight polyethylene;

[0012] And / or, the modified limestone is a powder of 35-200 mesh, and / or the modified granite is a powder of 35-200 mesh, and / or the modified ultramafic rock is a powder of 35-200 mesh, and / or the activated carbon is a powder of 80-325 mesh, and / or the binder is a powder of 80-325 mesh.

[0013] Optionally, in the filtered water of the filter element, the potassium content is 0.4 mg / L to 2 mg / L, the sodium content is 6 mg / L to 8 mg / L, the calcium content is 70 mg / L to 80 mg / L, the magnesium content is 25 mg / L to 30 mg / L, the strontium content is 0.4 mg / L to 1 mg / L, and the metasilicic acid content is 10 mg / L to 20 mg / L.

[0014] Secondly, this application provides a method for preparing a filter cartridge for drinking water that simulates the groundwater quality of the Alps, comprising the following steps:

[0015] Provide 90 to 110 parts of modified limestone, 45 to 55 parts of modified granite, 225 to 275 parts of modified ultramafic rock, 405 to 495 parts of activated carbon, and 405 to 495 parts of binder.

[0016] The modified limestone, the modified granite, the modified ultramafic rock, the activated carbon, and the binder are mixed to obtain a mixture. The mixture is then pressed into shape, fired to solidify, and then assembled to form a filter element.

[0017] Optionally, the method for preparing the modified granite includes the following steps:

[0018] Natural granite from the Alpine mineral water source is soaked in a first saturated alkaline solution for aluminum removal treatment. Then, the first system after the aluminum removal treatment is subjected to solid-liquid separation, and the solid first granite is collected.

[0019] The first granite was immersed in a first sodium citrate solution for a first acid treatment, and then the second system after the first acid treatment was subjected to solid-liquid separation to collect the solid second granite; and

[0020] The second granite was subjected to a first heat treatment at 600℃~650℃ to obtain the modified granite;

[0021] And / or, the method for preparing the modified ultramafic rock includes the following steps:

[0022] The first ultramafic rock was obtained by using a magnetic separator to remove iron from the natural ultramafic rock sourced from the Alps mineral water production area.

[0023] The first ultramafic rock was soaked in a second saturated alkaline solution for aluminum and manganese removal treatment. Then, the third system after the aluminum and manganese removal treatment was subjected to solid-liquid separation to collect the solid second ultramafic rock.

[0024] The second ultramafic rock was immersed in a second sodium citrate solution for a second acid treatment, and then the fourth system after the second acid treatment was subjected to solid-liquid separation to collect the solid third ultramafic rock; and

[0025] The third ultramafic rock was subjected to a second heat treatment at 600℃~650℃ to obtain the modified ultramafic rock.

[0026] Optionally, the solute in the first saturated alkaline solution and the solute in the second saturated alkaline solution are independently selected from one or more of calcium hydroxide, sodium carbonate, calcium carbonate and sodium bicarbonate. Preferably, the solute in the first saturated alkaline solution and the solute in the second saturated alkaline solution are selected from calcium carbonate.

[0027] And / or, the aluminum removal treatment includes the following steps: taking a mass of natural granite equivalent to that of the modified granite in the filter element and immersing it in 450 mL to 550 mL of the first saturated alkaline solution for 40 h to 48 h, wherein the natural granite is a powder of 35 mesh to 200 mesh;

[0028] And / or, take the first granite with a mass equivalent to the modified granite in the filter element and soak it in 500 mL of pure water at a temperature of 20℃~30℃ for 24 h to obtain the first granite soaking solution. In the first granite soaking solution, the aluminum content is less than 0.03 mg / L, preferably less than 0.01 mg / L.

[0029] And / or, the aluminum and manganese removal treatment includes the following steps: taking a mass of natural ultramafic rock equivalent to that of the modified ultramafic rock in the filter element and immersing it in 450 mL to 550 mL of the second saturated alkaline solution for 40 h to 48 h, wherein the natural ultramafic rock is a powder of 35 mesh to 200 mesh;

[0030] And / or, take a portion of the first ultramafic rock equivalent in mass to the modified ultramafic rock in the filter element and soak it in 500 mL of pure water at a temperature of 20℃~30℃ for 24 h to obtain a first ultramafic rock soaking solution, wherein the iron content in the first ultramafic rock soaking solution is less than 0.05 mg / mL; and / or, take a portion of the second ultramafic rock equivalent in mass to the modified ultramafic rock in the filter element and soak it in 500 mL of pure water at a temperature of 20℃~30℃ for 24 h to obtain a second ultramafic rock soaking solution, wherein the aluminum content in the second ultramafic rock soaking solution is less than 0.03 mg / L and the manganese content is less than 0.03 mg / L.

[0031] Optionally, in the first acid treatment, the mass ratio of the first granite to the sodium citrate in the first sodium citrate solution is 1:(0.861~1.107); and / or, the concentration of sodium citrate in the first sodium citrate solution is 0.5mol / L~4.5mol / L; and / or, the duration of the first acid treatment is 20h~30h.

[0032] And / or, in the second acid treatment, the mass ratio of the second ultramafic rock to sodium citrate in the second sodium citrate solution is 1:(0.861~1.107); and / or, the concentration of sodium citrate in the second sodium citrate solution is 0.5mol / L~4.5mol / L; and / or, the duration of the second acid treatment is 20h~30h.

[0033] Optionally, the method for preparing the modified limestone includes the steps of: placing natural limestone from the Alpine mineral water source in a carbon dioxide vapor atmosphere for hydrothermal modification treatment to obtain the modified limestone;

[0034] Wherein, the temperature of the carbon dioxide vapor atmosphere is 430℃~470℃, and / or the concentration of carbon dioxide in the carbon dioxide vapor atmosphere is 0.4mol / L~0.6mol / L, and / or the hydrothermal modification treatment time is 8h~15h;

[0035] And / or, in the filtered water of the filter element prepared by the method described above, the potassium content is 0.4 mg / L to 2 mg / L, the sodium content is 6 mg / L to 8 mg / L, the calcium content is 70 mg / L to 80 mg / L, the magnesium content is 25 mg / L to 30 mg / L, the strontium content is 0.4 mg / L to 1 mg / L, and the metasilicic acid content is 10 mg / L to 20 mg / L.

[0036] Thirdly, this application provides a water purification device, which includes a filter element as described in any of the first aspects, or the water purification device includes a filter element prepared by any of the preparation methods described in the second aspect.

[0037] This application provides a filter cartridge for drinking water that simulates the groundwater quality of the Alps, its preparation method, and a water purification device, which has the following technical advantages:

[0038] The mineralized filter element simulating Alpine groundwater quality provided in this application fully meets hygiene and safety requirements, has no excessive heavy metal content, and exhibits good uniformity. The mineral content of the filtered water is as follows: potassium 0.4 mg / L–2 mg / L, sodium 6 mg / L–8 mg / L, calcium 70 mg / L–80 mg / L, magnesium 25 mg / L–30 mg / L, strontium 0.4 mg / L–1 mg / L, and metasilicic acid 10 mg / L–20 mg / L. This conforms to the characteristics of Alpine groundwater quality, is beneficial to human health, and achieves the goal of healthy drinking water. The filter element preparation method is simple and can be mass-produced industrially. By using the filter element provided in this application or the filter element prepared by the method described in this application in conjunction with a water purification device, drinking water with Alpine groundwater quality can be obtained. Detailed Implementation

[0039] The technical solutions of this application will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application. Furthermore, it should be understood that the specific implementation methods described herein are only for illustration and explanation of this application and are not intended to limit this application.

[0040] The various embodiments of this application may exist in the form of a range; it should be understood that the description in the form of a range is merely for convenience and brevity and should not be construed as a hard limitation on the scope of the invention; therefore, it should be considered that the range description has specifically disclosed all possible sub-ranges and single numerical values ​​within that range. For example, it should be considered that the range description from 1 to 6 has specifically disclosed sub-ranges, such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., and single numbers within the corresponding ranges, such as 1, 2, 3, 4, 5, and 6, regardless of the range. Furthermore, whenever a numerical range is referred to herein, it means including any referenced number (fraction or integer) within the referred range.

[0041] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as are familiar to those skilled in the art. Furthermore, any methods and materials similar to or equivalent to those described herein may be used in this application. The preferred embodiments and materials described herein are for illustrative purposes only and do not limit the scope of this application.

[0042] The term "including" means "including but not limited to".

[0043] The term "and / or" encompasses any one of two or more of the listed items, as well as any and all combinations of the listed items. These combinations include any two listed items, any number of listed items, or a combination of all listed items. For example, "A and / or B" includes three parallel solutions: A, B, and A+B. Similarly, the technical solution "A, and / or, B, and / or, C, and / or, D" includes any one of A, B, C, and D (i.e., all connected by "logical OR"), any and all combinations of A, B, C, and D, including combinations of any two or three of A, B, C, and D, and combinations of all four of A, B, C, and D (i.e., all connected by "logical AND").

[0044] In the term "one or more," "more" refers to two or more items. The terms "one or more," "at least one," or similar expressions refer to any combination of these items, including any combination of single or multiple items. For example, "one or more of a, b, or c," or "one or more of a, b, and c," or "at least one" can all be expressed as: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, and c can each be single or multiple.

[0045] This application provides a filter element for drinking water that simulates the groundwater quality of the Alps. Calculated by mass fraction, the filter element includes: 90 to 110 parts of modified limestone, 45 to 55 parts of modified granite, 225 to 275 parts of modified ultramafic rock, 405 to 495 parts of activated carbon, and 405 to 495 parts of binder.

[0046] The characteristics of the Alpine groundwater are as follows: potassium content is 0.4 mg / L to 2 mg / L, sodium content is 6 mg / L to 8 mg / L, magnesium content is 25 mg / L to 30 mg / L, calcium content is 70 mg / L to 80 mg / L, strontium content is 0.4 mg / L to 1 mg / L, and metasilicic acid content is 10 mg / L to 20 mg / L. To achieve the quality of Alpine groundwater in drinking water, this application utilizes advanced rock modification technology and treatment methods to process rocks originating from the Alpine mineral water source, forming a mineralized filter element. This mineralized filter element can be used in conjunction with a water purifier, ensuring that the mineral element indicators in the filtered water are close to those in the Alpine groundwater, thus achieving the quality of Alpine groundwater and meeting the needs of healthy drinking water.

[0047] In some embodiments of this application, the modified granite is obtained by modifying natural granite sourced from the Alpine mineral water production area. A mass equivalent to that in the filter element is taken and soaked in 500 mL of pure water at a temperature of 20°C–30°C for 24 hours to obtain a modified granite soaking solution. In the modified granite soaking solution, the aluminum content is less than 0.03 mg / L, for example, less than 0.025 mg / L, less than 0.02 mg / L, less than 0.015 mg / L, less than 0.01 mg / L, or less than 0.005 mg / L. It should be noted that "a mass equivalent to that in the filter element" means that the mass of the modified granite used in the soaking experiment is the same as the mass of the modified granite required to make the filter element. For example, if the mass of modified granite required to make the filter element is 50 g, then 50 g of modified granite is soaked in 500 mL of pure water at a temperature of 20°C–30°C for 24 hours, and the aluminum content in the obtained modified granite soaking solution is less than 0.03 mg / L.

[0048] In some embodiments of this application, the modified ultramafic rock is obtained by modifying natural ultramafic rock originating from the Alpine mineral water source; a modified ultramafic rock mass equivalent to that in the filter cartridge is placed in 500 mL of pure water at a temperature of 20°C–30°C and soaked for 24 hours to obtain a modified ultramafic rock soaking solution; in the modified ultramafic rock soaking solution, the aluminum content is less than 0.03 mg / L, for example, less than 0.025 mg / L, less than 0.02 mg / L, or less than 0.015 mg / L. The concentrations of manganese and iron are as follows: L < 0.01 mg / L or < 0.005 mg / L, and the manganese content is below 0.03 mg / L (e.g., below 0.025 mg / L, 0.02 mg / L, 0.015 mg / L, 0.01 mg / L, or 0.005 mg / L). The iron content is below 0.05 mg / mL (e.g., below 0.04 mg / mL, 0.03 mg / mL, 0.02 mg / mL, or 0.01 mg / mL). It should be noted that "taking modified ultramafic rock of equivalent mass to that in the filter element" means that the mass of modified ultramafic rock used in the immersion experiment is the same as the mass of modified ultramafic rock required to make the filter element. For example, if the mass of modified ultramafic rock required to make the filter element is 250g, then 250g of modified ultramafic rock should be placed in 500mL of pure water at a temperature of 20℃~30℃ and immersed for 24h.

[0049] In some embodiments of this application, the modified limestone is obtained by modifying natural limestone originating from the Alpine mineral water production area; a composite mineralized carbon rod is prepared by taking the modified limestone, activated carbon and binder of equivalent mass to the filter element, and then the composite mineralized carbon rod is assembled into a test filter element. The calcium content in the filtered water of the test filter element is 73mg / L to 78mg / L, for example, 73mg / L to 74mg / L, 74mg / L to 75mg / L, 75mg / L to 76mg / L, 76mg / L to 77mg / L, or 77mg / L to 78mg / L.

[0050] In some embodiments of this application, the activated carbon is acid-washed coconut shell activated carbon, which is commercially available. For example, acid-washed coconut shell activated carbon is purchased from Jacobi Corporation, model number 88011222.

[0051] In some embodiments of this application, the binder is ultra-high molecular weight polyethylene (UHMWPE), with a relative molecular mass of, for example, 5,000,000 g / mol. UHMWPE is commercially available, for example, UHMWPE purchased from Dongguan Jinghong Polymer Materials Co., Ltd., model U050.

[0052] To further improve the quality of the filter element, in some embodiments of this application, the modified limestone is a powder of 35-200 mesh, and / or the modified granite is a powder of 35-200 mesh, and / or the modified ultramafic rock is a powder of 35-200 mesh, and / or the activated carbon is a powder of 80-325 mesh, and / or the binder is a powder of 80-325 mesh.

[0053] In order to make the filtered water of the filter element have the characteristics of drinking water of Alpine groundwater, in some embodiments of this application, the content of potassium in the filtered water of the filter element is 0.4 mg / L to 2 mg / L, the content of sodium is 6 mg / L to 8 mg / L, the content of calcium is 70 mg / L to 80 mg / L, the content of magnesium is 25 mg / L to 30 mg / L, the content of strontium is 0.4 mg / L to 1 mg / L, and the content of metasilicic acid is 10 mg / L to 20 mg / L.

[0054] This application also provides a method for preparing a filter cartridge for drinking water that simulates the groundwater quality of the Alps. This method can be used to prepare any of the aforementioned filter cartridges for drinking water that simulates the groundwater quality of the Alps. The preparation method includes the following steps:

[0055] S1. Provide 90 to 110 parts of modified limestone, 45 to 55 parts of modified granite, 225 to 275 parts of modified ultramafic rock, 405 to 495 parts of activated carbon, and 405 to 495 parts of binder.

[0056] S2. Modified limestone, modified granite, modified ultramafic rock, activated carbon and binder are mixed to obtain a mixture. The mixture is pressed into shape and then fired to solidify. Finally, it is assembled to form a filter element.

[0057] In step S1, the modified limestone, modified granite, modified ultramafic rock, activated carbon, and binder are as described above.

[0058] In order to reduce the amount of aluminum precipitated in modified granite and increase the amount of metasilicic acid and strontium precipitated in modified granite, in some embodiments of this application, the preparation method of modified granite includes the following steps:

[0059] S1.11. Natural granite from the Alpine mineral water source is soaked in a first saturated alkaline solution for aluminum removal treatment. Then, the first system after aluminum removal treatment is subjected to solid-liquid separation, and the solid first granite is collected.

[0060] S1.12. The first granite is soaked in the first sodium citrate solution for the first acid treatment, and then the second system after the first acid treatment is subjected to solid-liquid separation to collect the solid second granite.

[0061] S1.13. The second granite is subjected to a first heat treatment at 600℃~650℃ to obtain modified granite.

[0062] In step S1.11, the solute of the first saturated alkaline solution is selected from one or more of calcium hydroxide, sodium carbonate, calcium carbonate, and sodium bicarbonate. Preferably, the solute of the first saturated alkaline solution is selected from calcium carbonate, and the solvent of the first saturated alkaline solution is, for example, water. The process parameters for aluminum removal treatment can be set according to actual needs, as long as the following conditions are met: take a first granite with a mass equivalent to that of the modified granite in the filter element and soak it in 500 mL of pure water at a temperature of 20℃~30℃ for 24 hours to obtain a first granite soaking solution; in the first granite soaking solution, the aluminum content is less than 0.03 mg / L, preferably less than 0.01 mg / L.

[0063] In some embodiments of this application, step S1.11 includes: taking natural granite of equivalent mass to the modified granite in the filter element and soaking it in 450 mL to 550 mL of a first saturated alkaline solution for 40 h to 48 h, wherein the natural granite is a powder of 35 mesh to 200 mesh.

[0064] In step S1.12, the first acid treatment can open up the blind pores of the granite, which is beneficial to improving the porosity of the granite. In order to improve the effect of the first acid treatment, in some embodiments of this application, the mass ratio of the first granite to the sodium citrate in the first sodium citrate solution is 1:(0.861~1.107), and / or the concentration of sodium citrate in the first sodium citrate solution is 0.5mol / L~4.5mol / L, and / or the first acid treatment time is 20h~30h.

[0065] In step S1.13, the first heat treatment can alter the dense structure of the granite and further improve its porosity. The first heat treatment can be carried out in a muffle furnace.

[0066] In steps S1.11 to S1.13, "solid-liquid separation" refers to all operations that can separate the solid and liquid phases in a system, including but not limited to one or more of filtration, centrifugation, and evaporation. It is understood that after the solid-liquid separation operation, the collected solids may be subjected to processes such as rinsing and drying.

[0067] As an example, the preparation method of modified granite includes the following steps: First, take 100g of 35-200 mesh granite and soak it in 500mL of saturated food-grade calcium carbonate solution for 40-48 hours. After soaking, filter out the granite material, rinse it several times with pure water, filter and dry it to obtain the first granite. Then, take 100g of the first granite (35-200 mesh) and soak it in 500mL of food-grade sodium citrate solution (3.5mol / L-4.5mol / L, temperature 25℃±5℃) for 24 hours. After soaking, filter out the granite material, rinse it several times with pure water, filter and dry it to obtain the second granite. Finally, take 50g of the second modified granite (35-200 mesh) and place it in a muffle furnace. Adjust the temperature of the muffle furnace to 600℃-650℃ and process it for 3 hours. Cool it to room temperature and remove it to obtain the modified granite.

[0068] In order to reduce the precipitation of aluminum and manganese in modified ultramafic rocks and increase the precipitation of metasilicic acid and strontium in modified ultramafic rocks, in some embodiments of this application, the preparation method of modified ultramafic rocks includes the following steps:

[0069] S1.21. Use a magnetic separator to remove iron from the natural ultramafic rock originating from the Alps mineral water source to obtain the first ultramafic rock.

[0070] S1.22. The first ultramafic rock is soaked in a second saturated alkaline solution for aluminum and manganese removal treatment. Then, the third system after the aluminum and manganese removal treatment is subjected to solid-liquid separation to collect the solid second ultramafic rock.

[0071] S1.23. The second ultramafic rock is soaked in the second sodium citrate solution for the second acid treatment, and then the fourth system after the second acid treatment is subjected to solid-liquid separation to collect the solid third ultramafic rock.

[0072] S1.24. The third ultramafic rock is subjected to a second heat treatment at 600℃~650℃ to obtain the modified ultramafic rock.

[0073] In step S1.21, the process parameters for iron removal can be set according to actual needs, provided that the following conditions are met: take a first ultramafic rock of equivalent mass to the modified ultramafic rock in the filter element and soak it in 500 mL of pure water at a temperature of 20℃~30℃ for 24 hours to obtain the first ultramafic rock soaking solution. In the first ultramafic rock soaking solution, the iron content is less than 0.05 mg / mL.

[0074] In step S1.22, the second saturated alkaline solution refers to the description of the first saturated alkaline solution above. The process parameters for aluminum and manganese removal can be set according to actual needs, provided the following conditions are met: Take a second ultramafic rock of equivalent mass to the modified ultramafic rock in the filter element and soak it in 500 mL of pure water at a temperature of 20℃~30℃ for 24 hours. The resulting second ultramafic rock soaking solution has an aluminum content of less than 0.03 mg / L and a manganese content of less than 0.03 mg / L.

[0075] In step S1.23, the second acid treatment can open up the blind pores of the ultramafic rock, which is beneficial to improving the porosity of the ultramafic rock. In order to improve the effect of the second acid treatment, in some embodiments of this application, the mass ratio of the second ultramafic rock to sodium citrate in the second sodium citrate solution is 1:(0.861~1.107), and / or the concentration of sodium citrate in the second sodium citrate solution is 0.5mol / L~4.5mol / L, and / or the second acid treatment time is 20h~30h.

[0076] In step S1.24, the second heat treatment can alter the dense structure of the ultramafic rock and further enhance its porosity. The second heat treatment can be carried out in a muffle furnace.

[0077] In steps S1.21 to S1.24, "solid-liquid separation" refers to all operations that can separate the solid and liquid phases in a system, including but not limited to one or more of filtration, centrifugation, and evaporation. It is understood that after the solid-liquid separation operation, the collected solids may be subjected to processes such as rinsing and drying.

[0078] As an example, the preparation method of modified ultramafic rock includes the following steps: First, take 500g of 35-200 mesh ultramafic rock and place it in an electromagnetic separator for iron removal treatment, setting the power to 35W-45W, to obtain the first ultramafic rock; then, take 300g of the 35-200 mesh first ultramafic rock and soak it in 500mL of saturated food-grade calcium carbonate solution for 40h-48h. After soaking, filter and collect the solid, wash the solid several times with pure water, filter and dry it to obtain the second ultramafic rock; then, take 300g of 35-200 mesh... 300g of 0-mesh second ultramafic rock was soaked in 500mL of food-grade sodium citrate solution with a concentration of 3.5mol / L to 4.5mol / L (temperature 25℃±5℃) for 24h. After soaking, the solution was filtered and the solid was collected. The solid was rinsed several times with pure water, filtered again and dried to obtain third ultramafic rock. Finally, 250g of 35-200 mesh third ultramafic rock was placed in a muffle furnace, the temperature of the muffle furnace was adjusted to 600℃ to 650℃, and the solution was treated for 3h. The solution was then cooled to room temperature and removed to obtain modified ultramafic rock.

[0079] To increase the calcium precipitation in modified limestone, in some embodiments of this application, the preparation method of modified limestone includes the steps of: placing natural limestone originating from the Alpine mineral water source in a carbon dioxide vapor atmosphere for hydrothermal modification treatment to obtain the modified limestone. The temperature of the carbon dioxide vapor atmosphere is 430℃~470℃, and / or the concentration of carbon dioxide in the carbon dioxide vapor atmosphere is 0.4mol / L~0.6mol / L, and / or the hydrothermal modification treatment time is 8h~15h.

[0080] As an example, the preparation method of modified limestone includes the following steps: take 200g of limestone with a mesh size of 35 to 200 mesh, place it in a carbon dioxide vapor atmosphere for hydrothermal modification treatment for 12h, wherein the temperature of the carbon dioxide vapor atmosphere is 450℃ and the concentration of carbon dioxide in the carbon dioxide vapor atmosphere is 0.5mol / L, then rinse it several times with pure water, filter and dry to obtain modified limestone.

[0081] This application also provides a water purification device, which includes a filter element for drinking water simulating Alpine groundwater quality as described in any of the embodiments of this application, or a filter element prepared by the method described in any of the embodiments of this application for simulating Alpine groundwater quality. The type of water purification device is not specifically limited; for example, it can be a progressive tightening water purification device, a self-cleaning water purification device, etc., and can be selected according to actual needs.

[0082] The following detailed description, with reference to specific embodiments, illustrates the filter element for drinking water simulating Alpine groundwater quality and its preparation method. Unless otherwise stated, all materials mentioned herein are commercially available. For example, acid-washed coconut shell activated carbon was purchased from Jacobi, model 88011222; ultra-high molecular weight polyethylene was purchased from Dongguan Jinghong Polymer Materials Co., Ltd., model U050.

[0083] Example 1: Screening of raw materials for preparing filter elements

[0084] In this embodiment, rocks from the Cachart springs region in Evian, France, were used for screening tests. The tested rocks included granite, alkaline volcanic rock, ultramafic rock, sandstone, limestone, and shale. 2000g of each type of rock was taken, ground into powder, and sieved to obtain powder particles of 35-200 mesh for later use.

[0085] First, 2g of 35-200 mesh powder from various test rocks was taken and subjected to compositional analysis. The results of the compositional analysis are shown in Table 1 below:

[0086] Table 1. Chemical composition of the six test rocks

[0087]

[0088] The composition of groundwater in the Alps is characterized by the following: potassium content of 0.4 mg / L–2 mg / L, sodium content of 6 mg / L–8 mg / L, calcium content of 70 mg / L–80 mg / L, magnesium content of 25 mg / L–30 mg / L, strontium content of 0.4 mg / L–1 mg / L, and metasilicic acid content of 10 mg / L–20 mg / L. It is characterized by high mineralization, high calcium and magnesium content, presence of metasilicic acid, and rich strontium. Based on the composition characteristics of the Alpine groundwater and the data in Table 1, it is clear that the Alpine groundwater could not have originated from the mineralization of a single rock, but rather from the synergistic mineralization of multiple rocks. Therefore, it is not possible to determine whether a specific rock was used to simulate the Alpine groundwater based on a single element; further rock analysis is required.

[0089] Second, 200g of 35-200 mesh powder from various test rocks were taken and placed in 500mL of pure water. After soaking at a constant temperature of 25℃±5℃ for 24h, the supernatant was taken for component content analysis. The component analysis of the soaking supernatant of granite and alkaline volcanic rock is shown in Table 2 below:

[0090] Table 2. Component content of soaking supernatant from granite and alkaline volcanic rocks.

[0091]

[0092] Note: ND indicates that it was not detected.

[0093] The component analysis of the soaking supernatant of ultramafic rocks and sandstones is shown in Table 3 below:

[0094] Table 3. Summary of component contents in the soaking supernatant of ultramafic rocks and sandstones

[0095]

[0096]

[0097] Note: ND indicates that it was not detected.

[0098] The component analysis of the soaking supernatant of limestone and shale is shown in Table 4 below:

[0099] Table 4. Summary of component contents in the soaking supernatant of limestone and shale

[0100]

[0101] Note: ND indicates that it was not detected.

[0102] Based on the compositional characteristics of groundwater in the Alps and the data in Tables 2 to 4, it can be seen that, considering the potassium precipitation index in the soaking supernatant, the potassium precipitation in the supernatant of granite and alkaline volcanic rocks is too high, making them unsuitable as raw materials for potassium mineralization. The potassium precipitation in the supernatant of limestone and shale is too low, making them unsuitable as raw materials for potassium mineralization. The potassium precipitation in the supernatant of ultramafic rocks and sandstone is suitable, making them suitable as raw materials for potassium mineralization.

[0103] Based on the sodium precipitation index in the soaking supernatant, alkaline volcanic rocks exhibit excessively high sodium precipitation, making them unsuitable as raw materials for sodium mineralization. Sandstone, limestone, and shale show excessively low sodium precipitation, also making them unsuitable. Granite and ultramafic rocks, on the other hand, show suitable sodium precipitation in their soaking supernatants, making them suitable as raw materials for sodium mineralization.

[0104] Based on the calcium precipitation index in the soaking supernatant, alkaline volcanic rocks, sandstone, granite, ultramafic rocks, and shale show excessively low calcium precipitation, making them unsuitable as raw materials for calcium mineralization. Limestone, on the other hand, exhibits a suitable calcium precipitation in its soaking supernatant, making it suitable as a raw material for calcium mineralization.

[0105] Based on the magnesium precipitation index in the soaking supernatant, the magnesium precipitation in the soaking supernatant of alkaline volcanic rocks, sandstone, granite, and limestone is too low, making them unsuitable as raw materials for magnesium mineralization. The magnesium precipitation in the soaking supernatant of ultramafic rocks is appropriate, making them suitable as raw materials for magnesium mineralization.

[0106] Based on the strontium precipitation index in the soaking supernatant, alkaline volcanic rocks, sandstone, shale, and limestone show excessively low strontium precipitation levels, making them unsuitable as raw materials for strontium mineralization. Ultramafic rocks also exhibit low strontium precipitation levels, making them unsuitable as raw materials for strontium mineralization. Granite, however, shows suitable strontium precipitation levels in its soaking supernatant, making it a suitable raw material for strontium mineralization.

[0107] Based on the precipitation index of metasilicic acid in the soaking supernatant, granite, alkaline volcanic rocks, and shale showed high metasilicic acid precipitation levels, suggesting they could be considered as raw materials for metasilicic acid mineralization if their amounts are reduced. Sandstone and limestone showed excessively low metasilicic acid precipitation levels, making them unsuitable as raw materials for metasilicic acid mineralization. While sandstone has a high silica content, its low metasilicic acid precipitation may be due to its chemical composition preventing silica from converting into metasilicic acid. Ultramafic rocks showed suitable metasilicic acid precipitation levels in their soaking supernatants, making them suitable as raw materials for metasilicic acid mineralization.

[0108] In summary, the availability of the six test rocks is shown in Table 5 below:

[0109] Table 5. Overview of the availability of the six types of test rocks.

[0110]

[0111] Table 5 shows that only limestone may meet the functional requirements for calcium; therefore, limestone is chosen as one of the raw materials for the filter element. Only ultramafic rocks may meet the functional requirements for magnesium; therefore, ultramafic rocks are chosen as one of the raw materials for the filter element. Only granite may meet the functional requirements for strontium; therefore, granite is chosen as one of the raw materials for the filter element. Furthermore, ultramafic rocks and granite may also meet the functional requirements for potassium, sodium, and metasilicic acid. Considering the limitations on the amount of filter media added, it is better to use fewer types of rocks. In conclusion, limestone, ultramafic rocks, and granite are chosen as the raw materials for the filter element.

[0112] Example 2: Modification treatment of the raw materials for preparing filter elements

[0113] As shown in Example 1, since the aluminum precipitation in the soaking supernatant of granite is too high (unacceptable), the granite needs to be modified to reduce the aluminum precipitation in the soaking supernatant. Similarly, since the aluminum, iron, and manganese precipitation in the soaking supernatant of ultramafic rock is too high (unacceptable), the ultramafic rock needs to be modified to reduce the aluminum, iron, and manganese precipitation in the soaking supernatant.

[0114] 2.1 Modify the granite to reduce the amount of aluminum precipitated in the soaking supernatant.

[0115] To reduce the amount of aluminum precipitated in the supernatant of granite soaking, an alkaline method was used to remove aluminum from the granite. The aluminum removal process included the following steps: First, 100g of natural granite (35-200 mesh) was soaked in 500mL of a first saturated alkaline solution for 48 hours (samples were taken every hour); then, the first system after aluminum removal was filtered, and the resulting solid was collected; next, the solid was rinsed several times with pure water, filtered, and dried to obtain the first granite; finally, 50g of the first granite was weighed and soaked in 500mL of pure water at 25℃ for 24 hours, the supernatant was collected, and the aluminum content in the supernatant was tested. Water was used as the solvent in the first saturated alkaline solution. Sodium hydroxide, calcium hydroxide, sodium carbonate, calcium carbonate, and sodium bicarbonate were used as solutes in the first saturated alkaline solution, and the aluminum removal capabilities of the five alkalis were compared. To ensure that the natural granite met drinking water safety standards after aluminum removal treatment, food-grade sodium hydroxide, calcium hydroxide, sodium carbonate, calcium carbonate, and sodium bicarbonate were used in the experiment. The test results are shown in Table 6 below.

[0116] Table 6. Aluminum content in the leaching supernatant of natural granite after alkali treatment.

[0117]

[0118]

[0119] Table 6 shows that saturated calcium carbonate solution exhibits the best aluminum removal ability for natural granite. After 48 hours of continuous modification, the aluminum content in the soaking supernatant can be reduced to below 0.01 mg / L. The aluminum removal abilities of saturated sodium carbonate, sodium bicarbonate, and calcium hydroxide solutions for natural granite show little difference, and their removal abilities are all inferior to those of saturated calcium carbonate solution, but superior to those of saturated sodium hydroxide solution. This indicates that excessively high or low pH values ​​of the first saturated alkaline solution negatively impact aluminum removal. Furthermore, compared to the aluminum content in the soaking supernatant of natural granite, the aluminum content in the soaking supernatant after treatment with saturated sodium hydroxide solution actually increases, indicating that saturated sodium hydroxide solution promotes aluminum precipitation and cannot be used as the first saturated alkaline solution.

[0120] In summary, the preferred first saturated alkaline solution is a calcium carbonate saturated aqueous solution, and the aluminum removal treatment time is 40h to 48h. The granite treated with calcium carbonate saturated aqueous solution for 48h is named the first granite.

[0121] 2.2 Modification treatment of ultramafic rocks to reduce the precipitation of iron, aluminum and manganese in the soaking supernatant.

[0122] To reduce the amount of iron leached from ultramafic rocks, a magnetic separator was used to remove iron from the natural ultramafic rocks. The iron removal process included the following steps: First, 5500g of natural ultramafic rocks with a mesh size of 35-200 mesh was taken and evenly divided into 11 portions (500g each), corresponding to Sample 1 to Sample 11. Samples 1 to 11 were placed in an electromagnetic separator for iron removal. The operating power of the magnetic separator was different for each sample, and the iron removal time was 5s for each sample. Then, the mass of each sample after iron removal was weighed. Finally, 250g of each sample after iron removal was weighed and placed in 500mL of pure water at 25℃ for constant temperature soaking for 24h. The supernatant was collected, and the iron content in the supernatant was detected. The detection results are shown in Table 7 below.

[0123] Table 7. Iron content in the supernatant of natural ultramafic rocks after iron removal treatment.

[0124]

[0125]

[0126] As shown in Table 7, with the gradual increase of the magnetic separator's operating power, the mass of the ultramafic rock sample after iron removal treatment gradually decreased, and the iron content in the soaking supernatant also gradually decreased. When the magnetic separator's power reached 35W, the iron content in the soaking supernatant already met the hygiene and safety requirements for drinking water, and the reduction in iron content in the soaking supernatant was limited. To reduce the cost of iron removal treatment, the optimal operating frequency of the magnetic separator was 35W–40W, and the iron removal treatment time was 3s–5s. Sample 8 was named the first ultramafic rock.

[0127] To reduce the precipitation of aluminum and manganese in the soaking supernatant of ultramafic rocks, an alkaline method was used to treat the first ultramafic rock for aluminum and manganese removal. The aluminum and manganese removal treatment included the following steps: First, 300g of the first ultramafic rock (35-200 mesh) was soaked in 500mL of a second saturated alkaline solution for 48 hours (samples were taken every hour); then, the third system after aluminum and manganese removal treatment was filtered, and the obtained third solid was collected; next, the third solid was washed several times with pure water, filtered, and dried to obtain the second ultramafic rock; finally, 250g of the second ultramafic rock was weighed and placed in 500mL of pure water at 25℃ for constant temperature soaking for 24 hours, the supernatant was collected, and the aluminum and manganese content in the supernatant was detected. In this study, water was used as the solvent for the second saturated alkaline solution. Sodium hydroxide, calcium hydroxide, sodium carbonate, calcium carbonate, and sodium bicarbonate were used as solutes in the second saturated alkaline solution, and their aluminum removal capabilities were compared. To ensure that the first ultramafic rock could meet drinking water safety standards after aluminum and manganese removal treatment, food-grade sodium hydroxide, calcium hydroxide, sodium carbonate, calcium carbonate, and sodium bicarbonate were used in the experiment. The test results are shown in Table 8 below.

[0128] Table 8. Aluminum and manganese content in the leaching supernatant of the first ultramafic rock after alkali treatment.

[0129]

[0130] Table 8 shows that saturated calcium carbonate solution exhibits the best aluminum and manganese removal ability on the first ultramafic rock. After 48 hours of continuous modification, the aluminum content in the soaking supernatant can be reduced to below 0.017 mg / L, and the manganese content to below 0.014 mg / L. Saturated sodium carbonate, sodium bicarbonate, and calcium hydroxide solutions are all less effective at removing aluminum and manganese from the first ultramafic rock than saturated calcium carbonate solution, but better than saturated sodium hydroxide solution. This indicates that excessively high or low pH values ​​of the second saturated alkaline solution negatively impact the aluminum and manganese removal ability. Furthermore, compared to the aluminum content in the soaking supernatant of the first ultramafic rock, the aluminum and manganese contents in the soaking supernatant treated with saturated sodium hydroxide solution actually increased, indicating that saturated sodium hydroxide solution can promote the precipitation of aluminum and manganese and cannot be used as the second saturated alkaline solution.

[0131] In summary, the preferred second saturated alkaline solution is a calcium carbonate saturated aqueous solution, and the aluminum and manganese removal treatment time is 40h to 48h. The first ultramafic rock treated with calcium carbonate saturated aqueous solution for 48h is named the second ultramafic rock.

[0132] After reducing the aluminum precipitation in the soaking supernatant of granite and the aluminum and manganese precipitation in ultramafic rocks, the functional indicators of the pre-designed filter media formulation were verified. Based on the characteristics of groundwater in the Alps, the pre-designed filter media formulation was as follows: 100g of 35-200 mesh natural limestone, 50g of 35-200 mesh first-type granite, 250g of 35-200 mesh second-type ultramafic rock, 450g of 80-325 mesh acid-washed coconut shell activated carbon, and 450g of 80-325 mesh ultra-high molecular weight polyethylene. The raw materials were weighed and mixed according to the above formulation to obtain a mixture. This mixture was then placed into a filter cartridge mold and pressed into shape. After firing at 200℃ for 2 hours, the composite mineralized carbon rods were obtained after demolding. The dimensions of the composite mineralized carbon rods were all 110mm × 50mm × 250mm.

[0133] Composite mineralized carbon rods were assembled into a large-sized filter element. Pure water was continuously passed through the filter at a temperature of 25℃ and a flow rate of 0.2L / min. The filtered water was collected when the pure water flow rate was 10L, and the contents of potassium, sodium, calcium, magnesium, strontium, and metasilicic acid in the filtered water were measured. The test results are shown in Table 9 below:

[0134] Table 9. Composition of water filtered by filter cartridges assembled from composite mineralized carbon rods.

[0135]

[0136] Based on the characteristics of groundwater in the Alps and the data in Table 9, the contents of potassium, sodium, magnesium, strontium, and metasilicic acid in the effluent from the composite mineralized carbon rods meet the standards for Alpine groundwater quality. However, the contents of strontium and metasilicic acid are relatively low, and optimization and improvement can be considered. The calcium content in the effluent from the composite mineralized carbon rods does not meet the standards for Alpine groundwater quality. Therefore, further modification treatment of the natural limestone, the first granite, and the second ultramafic rock is necessary.

[0137] 2.3 Modification treatment of natural limestone

[0138] Natural limestone is characterized by its dense structure, but weathered limestone has a looser structure, which can increase the amount of minerals precipitated in water. In this embodiment, a carbon dioxide steam hydrothermal modification method is used to modify natural limestone to increase the amount of calcium precipitated in water. The steps include: placing 200g of 35-200 mesh natural limestone in a carbon dioxide steam atmosphere for hydrothermal modification treatment to obtain the first limestone; wherein the temperature of the carbon dioxide steam atmosphere is 450℃ and the concentration of carbon dioxide in the carbon dioxide steam atmosphere is 0.5mol / L. The hydrothermal modification treatment time is set to 2h, 3h, 5h, 8h, 12h and 15h, respectively, to obtain the first limestone sample 1 to the first limestone sample 6.

[0139] First limestone samples 1 to 6 were rinsed with pure water, then filtered and dried. 100g of each type of first limestone sample was taken and mixed with 450g of 80-325 mesh acid-washed coconut shell activated carbon and 450g of 80-325 mesh ultra-high molecular weight polyethylene to prepare first mineralized carbon rod samples, corresponding to first mineralized carbon rod samples 1 to 6. The preparation method of the first mineralized carbon rod samples included the following steps: weighing 100g of the first limestone sample, 450g of 80-325 mesh acid-washed coconut shell activated carbon, and 450g of 80-325 mesh ultra-high molecular weight polyethylene, mixing to obtain a mixture, then filling the mixture into a filter element mold and pressing it into shape, then firing it at 200℃ for 2 hours, and demolding to obtain the first mineralized carbon rod samples. The dimensions of first mineralized carbon rod samples 1 to 6 were all 110mm × 50mm × 250mm.

[0140] The first mineralized carbon rod samples 1 to 6 were assembled into large-sized filter cartridges. Pure water was continuously passed through the cartridges at a temperature of 25℃ and a flow rate of 0.2L / min. The filtered water was collected when the pure water flow rate was 10L, and the calcium content in the filtered water was measured. The results are shown in Table 10 below.

[0141] Table 10: Calcium content in the filtered water of filter cartridges assembled from first mineralized carbon rod samples 1 to 6.

[0142]

[0143] As shown in Table 10, when the hydrothermal modification treatment time is more than 8 hours, especially more than 12 hours, the calcium content in the filtered water is ideal. The first limestone sample 5 is named modified limestone.

[0144] 2.4 Modification treatment of the first granite.

[0145] The first granite and the second ultramafic rock were modified by a combination of acid treatment and high-temperature treatment to obtain modified granite and modified ultramafic rock, respectively.

[0146] The acid treatment includes the following steps: First, take an appropriate amount of 35-200 mesh single stone material (100g of the first type of granite or 300g of the second type of ultramafic rock), soak it in 500mL of a specific concentration of food-grade sodium citrate aqueous solution at a temperature of 25℃ for 24 hours; then, filter to obtain a solid, rinse the solid several times with pure water, and then filter and dry to obtain modified stone material.

[0147] A mixture was prepared by mixing 250g of acid-treated modified ultramafic rock, 50g of acid-treated modified granite (35-200 mesh), 450g of acid-washed coconut shell activated carbon (80-325 mesh), and 450g of ultra-high molecular weight polyethylene (80-325 mesh). The mixture was then placed into a filter cartridge mold and pressed, followed by firing at 200℃ for 2 hours. After demolding, a second mineralized carbon rod sample was obtained. Ten second mineralized carbon rod samples were prepared, corresponding to samples 1 to 10. In each sample, the ultramafic rock and granite materials were modified using the same concentration of food-grade sodium citrate aqueous solution. The difference between the ten samples lies in the different concentrations of food-grade sodium citrate aqueous solution used for acid treatment of the ultramafic rock and granite materials. The dimensions of the second mineralized carbon rod samples 1 to 10 are all 110mm × 50mm × 250mm.

[0148] Ten samples of second-mineralized carbon rods were assembled into large-sized filter cartridges. Pure water was continuously passed through the cartridges at a temperature of 25℃ and a flow rate of 0.2 L / min. The filtered water was collected when the pure water flow rate was 10 L, and the content of metasilicic acid and strontium in the filtered water was measured. The results are shown in Table 11 below.

[0149] Table 11: Summary of metasilicic acid and strontium content in the filtered water of filter cartridges assembled from second mineralized carbon rod samples 1 to 10.

[0150]

[0151]

[0152] Table 11 shows that during the acid treatment process, the concentration of the food-grade sodium citrate aqueous solution ranged from 0.5 mol / L to 4.5 mol / L. With increasing concentration, the content of metasilicic acid and strontium in the filtrate of the second mineralized carbon rod sample gradually increased. However, when the concentration of the food-grade sodium citrate aqueous solution was between 3.5 mol / L and 5.0 mol / L, the difference in the precipitation of metasilicic acid and strontium in the filtrate of the second mineralized carbon rod sample was minimal, and the increase in precipitation of metasilicic acid and strontium decreased. Therefore, the concentration of the food-grade sodium citrate aqueous solution can be in the range of 3.5 mol / L to 4.5 mol / L, and the acid treatment time should be 24 h. The ultramafic rock material obtained by acid treatment of the second ultramafic rock with a concentration of 3.5 mol / L food-grade sodium citrate aqueous solution for 24 h was named the third ultramafic rock, and the granite material obtained by acid treatment of the first granite with a concentration of 3.5 mol / L food-grade sodium citrate aqueous solution for 24 h was named the second granite.

[0153] The third ultramafic rock and the second granite were subjected to high-temperature treatment. The high-temperature treatment included the following steps: take an appropriate amount of single stone material of 35-200 mesh (50g of the second granite or 250g of the third ultramafic rock), place it in a muffle furnace, treat it at a specific temperature for 3 hours, and then cool it to room temperature before taking it out.

[0154] 250g of ultramafic rock material (35-200 mesh) obtained by high-temperature modification of the third ultramafic rock, 50g of granite material (35-200 mesh) obtained by high-temperature modification of the second granite, 450g of 80-325 mesh acid-washed coconut shell activated carbon, and 450g of 80-325 mesh ultra-high molecular weight polyethylene were mixed to form a mixture. The mixture was then placed into a filter element mold and pressed into shape, and then fired at 200℃ for 2 hours. After demolding, the third mineralized carbon rod sample was obtained. A total of ten third mineralized carbon rod samples were obtained, corresponding to third mineralized carbon rod sample 1 to third mineralized carbon rod sample 10. In each third mineralized carbon rod sample, the ultramafic rock material and granite material were obtained by modification at the same temperature. The difference between the different third mineralized carbon rod samples is that the high-temperature modification temperature of the mafic rock material and granite material in the raw materials is different. The dimensions of the third mineralized carbon rod samples 1 to 10 are all 110mm × 50mm × 250mm.

[0155] Each type of third-mineralized carbon rod sample was assembled into a large-sized filter element. Pure water was continuously passed through the filter element at a temperature of 25℃ and a flow rate of 0.2L / min. The filtered water was collected when the pure water flow rate was 10L, and the content of metasilicic acid and strontium in the filtered water was measured. The results are shown in Table 12 below.

[0156] Table 12: Summary of metasilicic acid and strontium content in the filtered water of filter cartridges assembled from third-mineralized carbon rod samples 1 to 10.

[0157]

[0158]

[0159] Table 12 shows that when the high-temperature treatment temperature is between 600℃ and 650℃, the contents of metasilicic acid and strontium in the filtrate of the third mineralized carbon rod sample reach their highest values. The ultramafic rock material obtained by modifying the third ultramafic rock at 650℃ is named modified ultramafic rock, and the granite material obtained by modifying the second granite at 650℃ is named modified granite.

[0160] Example 3: Filter cartridge for drinking water simulating Alpine groundwater quality and its preparation method

[0161] This embodiment provides a filter element for drinking water that simulates the groundwater quality of the Alps and its preparation method. Calculated by mass parts, the filter element includes: 100g of modified limestone (35-200 mesh), 50g of modified granite (35-200 mesh), 250g of modified ultramafic rock (35-200 mesh), 450g of acid-washed coconut shell activated carbon (80-325 mesh), and 450g of ultra-high molecular weight polyethylene (80-325 mesh).

[0162] The filter element preparation method in this embodiment includes the following steps:

[0163] S3.1 According to the filter element formula, weigh out 100g of modified limestone (35-200 mesh), 50g of modified granite (35-200 mesh), 250g of modified ultramafic rock (35-200 mesh), 450g of acid-washed coconut shell activated carbon (80-325 mesh), and 450g of ultra-high molecular weight polyethylene (80-325 mesh). The preparation methods of modified limestone, modified granite, and modified ultramafic rock are as described in Example 2.

[0164] S3.2. Mix the weighed raw materials to obtain a mixture, then put the mixture into a mold and press it into shape, then fire it at 200℃ for 2 hours. After demolding, a mineralized carbon rod simulating the groundwater quality of the Alps is obtained, with a size of 110mm×50mm×250mm.

[0165] S3.3 Assemble mineralized carbon rods that simulate the groundwater quality of the Alps to form a filter element.

[0166] In this embodiment, mineralized carbon rods simulating Alpine groundwater quality were assembled into a large-sized filter element. The filter element was then loaded into a pure water machine (TDS < 5) and rinsed for 30 minutes. After draining the water from the filter element, a soaking solution was prepared according to Appendix A of the "Standard for Hygienic Safety Evaluation of Drinking Water Transmission and Distribution Equipment and Protective Materials" (2001). The filter element was then rinsed with the soaking solution (flow rate 1.5 L / min). Timing began after water flow from the filter element. After 30 seconds of water flow, the inlet and outlet water switches of the filter element were closed. The filter element was left to stand for 24 hours at an ambient temperature of 25 ± 5℃. The inlet and outlet water switches of the filter element were then reopened, and the soaking water was collected for a hygienic safety test. The hygienic safety test results are shown in Table 13 below.

[0167] Table 13: Summary of Hygiene and Safety Immersion Test Results of Filter Cartridges for Drinking Water Simulating Alpine Groundwater Quality in This Embodiment

[0168]

[0169] Note: Blank is a standard water quality (immersion solution used in the safety verification of filter cartridge products) stipulated by the Ministry of Health of China. No. 1 and No. 2 are parallel samples of the immersion water of the filter cartridge in this embodiment.

[0170] As shown in Table 13, the filter element in this embodiment fully meets the hygiene and safety requirements and has the advantage of good uniformity.

[0171] Further, the mineralized carbon rods obtained in step S3.2 were assembled into a large-sized filter element. The filter element was then loaded into a pure water machine (TDS < 5), rinsed with 10L of pure water, and then continuously fed into the filter element with pure water at a temperature of 25℃ ± 3℃ at a flow rate of 0.2L / min. The mineral content in the filtered water was measured at pure water flow rates of 0L, 50L, 100L, 150L, ​​and 200L. The results are shown in Table 14 below.

[0172] Table 14: Mineral Indicators of Filter Cartridges for Drinking Water Simulating Alpine Groundwater Quality in This Embodiment

[0173]

[0174]

[0175] As shown in Table 14, when the pure water flow rate was 0L, 50L, 100L, 150L, ​​and 200L, the mineral indicators in the filtered water all met the composition characteristics of Alpine groundwater. The composition characteristics of Alpine groundwater are: potassium content of 0.4mg / L to 2mg / L, sodium content of 6mg / L to 8mg / L, calcium content of 70mg / L to 80mg / L, magnesium content of 25mg / L to 30mg / L, strontium content of 0.4mg / L to 1mg / L, and metasilicic acid content of 10mg / L to 20mg / L, which is beneficial to human health.

[0176] Comparative Example 1

[0177] This comparative example is commercially available Spanish Sanlán mineral water. The composition of Spanish Sanlán mineral water is as follows: potassium content is 0.43 mg / L, sodium content is 4.5 mg / L, calcium content is 52 mg / L, magnesium content is 25 mg / L, strontium content is 0.2 mg / L, and metasilicic acid content is 7.6 mg / L.

[0178] Comparative Example 2

[0179] This comparative example is commercially available Italian Sanpvita mineral water. The composition of Italian Sanpvita mineral water is as follows: potassium content is 0.39 mg / L, sodium content is 5.7 mg / L, calcium content is 44 mg / L, magnesium content is 29 mg / L, strontium content is 0.2 mg / L, and metasilicic acid content is 17.8 mg / L.

[0180] Comparative Example 3

[0181] This comparative example is commercially available Italian San Pellegrino mineral water. The composition of Italian San Pellegrino mineral water is as follows: potassium content is 1.4 mg / L, sodium content is 28.7 mg / L, calcium content is 150 mg / L, magnesium content is 48 mg / L, strontium content is 2.6 mg / L, and metasilicic acid content is 95 mg / L.

[0182] Comparative Example 4

[0183] This comparative example uses commercially available Kunlun Mountain Snow Mountain Mineral Water. The composition of Kunlun Mountain Snow Mountain Mineral Water is as follows: potassium content is 0.8 mg / L, sodium content is 31.5 mg / L, calcium content is 37 mg / L, magnesium content is 37 mg / L, strontium content is 0.6 mg / L, and metasilicic acid content is 6.5 mg / L.

[0184] The above provides a detailed description of a filter element for drinking water that simulates the groundwater quality of the Alps, its preparation method, and a water purification device provided in the embodiments of this application. Specific examples have been used to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A filter element for drinking water that simulates the groundwater quality of the Alps, characterized in that, According to the mass fractions, the filter element comprises: 90 to 110 parts of modified limestone, 45 to 55 parts of modified granite, 225 to 275 parts of modified ultramafic rock, 405 to 495 parts of activated carbon, and 405 to 495 parts of binder. The method for preparing the modified granite includes the following steps: Natural granite from the Alpine mineral water source is soaked in a first saturated alkaline solution for aluminum removal treatment. Then, the first system after the aluminum removal treatment is subjected to solid-liquid separation, and the solid first granite is collected. The first granite was immersed in a first sodium citrate solution for a first acid treatment, and then the second system after the first acid treatment was subjected to solid-liquid separation to collect the solid second granite; and The second granite was subjected to a first heat treatment at 600 ℃~650 ℃ to obtain the modified granite; The preparation method of the modified ultramafic rock includes the following steps: The first ultramafic rock was obtained by using a magnetic separator to remove iron from the natural ultramafic rock sourced from the Alps mineral water production area. The first ultramafic rock was soaked in a second saturated alkaline solution for aluminum and manganese removal treatment. Then, the third system after the aluminum and manganese removal treatment was subjected to solid-liquid separation to collect the solid second ultramafic rock. The second ultramafic rock was immersed in a second sodium citrate solution for a second acid treatment, and then the fourth system after the second acid treatment was subjected to solid-liquid separation to collect the solid third ultramafic rock; and The third ultramafic rock was subjected to a second heat treatment at 600 ℃~650 ℃ to obtain the modified ultramafic rock. The method for preparing the modified limestone includes the following steps: placing natural limestone from the Alpine mineral water source into a carbon dioxide vapor atmosphere for hydrothermal modification treatment to obtain the modified limestone; wherein the temperature of the carbon dioxide vapor atmosphere is 430 ℃~470 ℃, and / or the concentration of carbon dioxide in the carbon dioxide vapor atmosphere is 0.4 mol / L~0.6 mol / L, and / or the hydrothermal modification treatment time is 8 h~15 h.

2. The filter element according to claim 1, characterized in that, The modified granite is obtained by modifying natural granite from the Alpine mineral water source; a mass of the modified granite equivalent to that in the filter element is placed in 500 mL of pure water at a temperature of 20 ℃~30 ℃ and soaked for 24 h to obtain a modified granite soaking solution; in the modified granite soaking solution, the aluminum content is less than 0.03 mg / L; And / or, the modified ultramafic rock is obtained by modifying natural ultramafic rock originating from the Alpine mineral water source; a modified ultramafic rock of equivalent mass to that in the filter element is placed in 500 mL of pure water at a temperature of 20 ℃~30 ℃ and soaked for 24 h to obtain a modified ultramafic rock soaking solution; in the modified ultramafic rock soaking solution, the aluminum content is less than 0.03 mg / L, the manganese content is less than 0.03 mg / L, and the iron content is less than 0.05 mg / mL; And / or, the modified limestone is obtained by modifying natural limestone originating from the Alpine mineral water production area; the modified limestone, the activated carbon and the binder of equivalent mass to those in the filter element are used to prepare a composite mineralized carbon rod, and the composite mineralized carbon rod is then assembled into a test filter element, wherein the calcium content in the filtered water of the test filter element is 73 mg / L to 78 mg / L.

3. The filter element according to claim 1, characterized in that, The activated carbon is acid-washed coconut shell activated carbon, and / or the binder is ultra-high molecular weight polyethylene; And / or, the modified limestone is a powder of 35-200 mesh, and / or the modified granite is a powder of 35-200 mesh, and / or the modified ultramafic rock is a powder of 35-200 mesh, and / or the activated carbon is a powder of 80-325 mesh, and / or the binder is a powder of 80-325 mesh.

4. The filter element according to any one of claims 1 to 3, characterized in that, In the filtered water from the filter element, the potassium content is 0.4 mg / L to 2 mg / L, the sodium content is 6 mg / L to 8 mg / L, the calcium content is 70 mg / L to 80 mg / L, the magnesium content is 25 mg / L to 30 mg / L, the strontium content is 0.4 mg / L to 1 mg / L, and the metasilicic acid content is 10 mg / L to 20 mg / L.

5. A method for preparing a filter element for drinking water that simulates the groundwater quality of the Alps, used to prepare the filter element according to any one of claims 1 to 4, characterized in that, The steps include the following: Provide 90 to 110 parts of modified limestone, 45 to 55 parts of modified granite, 225 to 275 parts of modified ultramafic rock, 405 to 495 parts of activated carbon, and 405 to 495 parts of binder. The modified limestone, the modified granite, the modified ultramafic rock, the activated carbon, and the binder are mixed to obtain a mixture. The mixture is then pressed into shape, fired to solidify, and then assembled to form a filter element. The method for preparing the modified granite includes the following steps: Natural granite from the Alpine mineral water source is soaked in a first saturated alkaline solution for aluminum removal treatment. Then, the first system after the aluminum removal treatment is subjected to solid-liquid separation, and the solid first granite is collected. The first granite was immersed in a first sodium citrate solution for a first acid treatment, and then the second system after the first acid treatment was subjected to solid-liquid separation to collect the solid second granite; and The second granite was subjected to a first heat treatment at 600 ℃~650 ℃ to obtain the modified granite; The preparation method of the modified ultramafic rock includes the following steps: The first ultramafic rock was obtained by using a magnetic separator to remove iron from the natural ultramafic rock sourced from the Alps mineral water production area. The first ultramafic rock was soaked in a second saturated alkaline solution for aluminum and manganese removal treatment. Then, the third system after the aluminum and manganese removal treatment was subjected to solid-liquid separation to collect the solid second ultramafic rock. The second ultramafic rock was immersed in a second sodium citrate solution for a second acid treatment, and then the fourth system after the second acid treatment was subjected to solid-liquid separation to collect the solid third ultramafic rock; and The third ultramafic rock was subjected to a second heat treatment at 600 ℃~650 ℃ to obtain the modified ultramafic rock. The method for preparing the modified limestone includes the following steps: placing natural limestone from the Alpine mineral water source into a carbon dioxide vapor atmosphere for hydrothermal modification treatment to obtain the modified limestone; wherein the temperature of the carbon dioxide vapor atmosphere is 430 ℃~470 ℃, and / or the concentration of carbon dioxide in the carbon dioxide vapor atmosphere is 0.4 mol / L~0.6 mol / L, and / or the hydrothermal modification treatment time is 8 h~15 h.

6. The preparation method according to claim 5, characterized in that, The solute in the first saturated alkaline solution and the solute in the second saturated alkaline solution are independently selected from one or more of calcium hydroxide, sodium carbonate, calcium carbonate, and sodium bicarbonate. And / or, the aluminum removal treatment includes the following steps: taking a mass of natural granite equivalent to that of the modified granite in the filter element and immersing it in 450 mL to 550 mL of the first saturated alkaline solution for 40 h to 48 h, wherein the natural granite is a powder of 35 mesh to 200 mesh; And / or, take the first granite with a mass equivalent to the modified granite in the filter element and soak it in 500 mL of pure water at a temperature of 20 ℃~30 ℃ for 24 h to obtain the first granite soaking solution, in which the aluminum content is less than 0.03 mg / L; And / or, the aluminum and manganese removal treatment includes the following steps: taking a mass of natural ultramafic rock equivalent to that of the modified ultramafic rock in the filter element and immersing it in 450 mL to 550 mL of the second saturated alkaline solution for 40 h to 48 h, wherein the natural ultramafic rock is a powder of 35 mesh to 200 mesh; And / or, take a portion of the first ultramafic rock equivalent in mass to the modified ultramafic rock in the filter element and soak it in 500 mL of pure water at a temperature of 20 ℃~30 ℃ for 24 h to obtain a first ultramafic rock soaking solution, wherein the iron content in the first ultramafic rock soaking solution is less than 0.05 mg / mL; and / or, take a portion of the second ultramafic rock equivalent in mass to the modified ultramafic rock in the filter element and soak it in 500 mL of pure water at a temperature of 20 ℃~30 ℃ for 24 h to obtain a second ultramafic rock soaking solution, wherein the aluminum content in the second ultramafic rock soaking solution is less than 0.03 mg / L and the manganese content is less than 0.03 mg / L.

7. The preparation method according to claim 6, characterized in that, The solute in the first saturated alkaline solution and the solute in the second saturated alkaline solution are selected from calcium carbonate; And / or, in the first granite soaking solution, the aluminum content is less than 0.01 mg / L.

8. The preparation method according to claim 5, characterized in that, In the first acid treatment, the mass ratio of the first granite to sodium citrate in the first sodium citrate solution is 1:(0.861~1.107); and / or, the concentration of sodium citrate in the first sodium citrate solution is 0.5 mol / L~4.5 mol / L; and / or, the duration of the first acid treatment is 20 h~30 h. And / or, in the second acid treatment, the mass ratio of the second ultramafic rock to sodium citrate in the second sodium citrate solution is 1:(0.861~1.107); and / or, the concentration of sodium citrate in the second sodium citrate solution is 0.5 mol / L~4.5 mol / L; and / or, the duration of the second acid treatment is 20 h~30 h.

9. The preparation method according to any one of claims 5 to 8, characterized in that, In the filtered water of the filter element prepared by the above preparation method, the potassium content is 0.4 mg / L to 2 mg / L, the sodium content is 6 mg / L to 8 mg / L, the calcium content is 70 mg / L to 80 mg / L, the magnesium content is 25 mg / L to 30 mg / L, the strontium content is 0.4 mg / L to 1 mg / L, and the metasilicic acid content is 10 mg / L to 20 mg / L.

10. A water purification device, characterized in that, The water purification device includes a filter element as described in any one of claims 1 to 4, or the water purification device includes a filter element prepared by the preparation method as described in any one of claims 5 to 9.

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