Simulated water for testing ultrafiltration water purifier as well as preparation method and application of simulated water

Abstract

The invention provides simulated water for testing an ultrafiltration water purifier as well as a preparation method and application of the simulated water. The simulated water for testing the ultrafiltration water purifier comprises test water, escherichia coli, humic acid, montmorillonite, aluminum hydroxide and aluminum sulfate. The concentration of montmorillonite in the simulated water for testing the ultrafiltration water purifier is 0.5-2g / L. The preparation method of the simulated water for testing the ultrafiltration water purifier is simple to operate, the bacterial solution, the humic acid stock solution, the montmorillonite stock solution, the aluminum hydroxide stock solution and the aluminum sulfate are mixed with the test water to prepare the simulated water containing colloids, organic matters and bacteria, and the water quality of various tap water can be accurately simulated; the method can be used for evaluating and testing the performance of the ultrafiltration water purifier filter element, field water taking testing is not needed, and the filter element testing cost is reduced.

Description

Technical Field

[0001] This invention relates to the field of simulated water technology, and in particular to a simulated water for testing ultrafiltration water purifiers, its preparation method, and its uses. Background Technology

[0002] Ultrafiltration water purifiers are an indispensable water purification device in household appliances. The test water is mainly tap water from various regions. However, due to the large differences in the content of colloids, organic matter, and bacteria in tap water from different regions, the test results of the water purifier at the manufacturer's local area cannot be applied to different water quality areas. As a result, the ultrafiltration machine passes the factory test, but when it is sold to other areas with poor water quality, the filter cartridge often becomes clogged.

[0003] CN112697675A discloses simulated tap water and its application. The simulated tap water includes water and humic acid used to simulate organic matter, wherein the humic acid has a number-average molecular weight of 1000-2200. This simulated tap water can accurately simulate water quality in various regions, quickly reproduce after-sales problems of water purifiers in different areas, save manpower and resources, and enhance the practicality of the water quality simulation system.

[0004] CN103877862A discloses a simulated tap water and its uses. The simulated tap water is composed of polyvinylpyrrolidone (PVP), nano-silica particles, nano-iron oxide particles, sodium humate, sodium alginate, NaHCO3, MgSO4, and CaCl2. This simulated tap water test solution fills a gap in water quality evaluation methods, establishes a standard test solution, improves the evaluation methods for water purification membranes and water supply membranes, and avoids discrepancies in membrane evaluation results caused by varying tap water quality across different regions.

[0005] However, the simulated tap water mentioned above did not take into account colloids and bacteria in the water, which still presents certain problems when evaluating the performance of water purifier filter cartridges. Summary of the Invention

[0006] To address the aforementioned technical problems, this invention provides a simulated water for testing ultrafiltration water purifiers, its preparation method, and its uses. The simulated water, containing colloids, organic matter, and microorganisms, effectively simulates tap water from various regions, enabling realistic evaluation and testing of the performance of water purifier filter cartridges and allowing water purification equipment to meet different water quality requirements in various regions.

[0007] To achieve this objective, the present invention adopts the following technical solution:

[0008] In a first aspect, the present invention provides simulated water for testing an ultrafiltration water purifier, wherein the simulated water for testing the ultrafiltration water purifier includes test water, Escherichia coli, humic acid, montmorillonite, aluminum hydroxide and aluminum sulfate; the concentration of montmorillonite in the simulated water for testing the ultrafiltration water purifier is 0.5 to 2 g / L.

[0009] The water quality requirements for the test water described in this invention are as follows: total hardness controlled at (250±20) mg / L; alkalinity controlled at (160±20) mg / L; pH controlled at 7 to 7.5.

[0010] The test water is prepared by adding spiked pure water (conductivity <10μS / cm, TDS <5mg / L) according to the following steps (taking the preparation of 100L of test water as an example):

[0011] a) Weigh out 61.56g of magnesium sulfate (MgSO4) . 7H2O) and 26.88g of anhydrous sodium bicarbonate (NaHCO3) were dissolved in a small amount of pure water respectively;

[0012] b) Add each of the above solutions separately to 100L of pure water. Stir well immediately after adding each solution, and then continue stirring for a while to ensure thorough mixing.

[0013] c) Take 5 mL to 10 mL of 5.2% sodium hypochlorite (NaClO) stock solution, dilute it with pure water to 1 L, then take 100 mL of this diluted solution and add it to the above 100 L of water, and stir immediately until well mixed.

[0014] d) Adjust the pH to the range of 7.0 to 7.5 using sodium hydroxide (NaOH) or hydrochloric acid (HCl);

[0015] e) The prepared test water should be stored in a light-proof, sealed container and should be prepared and used immediately. Test water prepared overnight should not be used. Note: All chemical reagents used are of analytical grade or equivalent purity.

[0016] The simulated water for testing the ultrafiltration water purifier described in this invention fully considers the different types of substances, colloids, organic matter, and bacteria contained in tap water from various regions. By preparing these substances in the test water, it can more accurately simulate water samples with various water quality conditions, thus solving the problem that ultrafiltration water purifier filter cartridges can only be tested with local tap water due to the different water quality in different regions.

[0017] In this invention, humic acid is used to simulate organic matter in water, and montmorillonite, aluminum hydroxide and aluminum sulfate are used to simulate colloids in water. The main function of montmorillonite is to form aluminum and silicon colloids.

[0018] The concentration of montmorillonite in the simulated water used for testing the ultrafiltration water purifier described in this invention is 0.5 to 2 g / L, for example, it can be 0.5 g / L, 0.6 g / L, 0.8 g / L, 1 g / L, 1.5 g / L or 2 g / L, but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0019] In this invention, montmorillonite serves to form a colloidal solution. However, colloidal solutions are prone to aggregation and precipitation, while the colloid formed by montmorillonite is relatively stable within a certain range. When the concentration of montmorillonite in the simulated water used in the ultrafiltration water purifier test is too low or too high, it will lead to instability of the colloid.

[0020] Preferably, the concentration of E. coli in the simulated water used for testing the ultrafiltration water purifier is 1000-2000 CFU / mL, for example, it can be 1000 CFU / mL, 1200 CFU / mL, 1500 CFU / mL, 1700 CFU / mL, 1900 CFU / mL or 2000 CFU / mL, but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0021] Preferably, the humic acid in the simulated water used for testing the ultrafiltration water purifier has a molecular weight of 10. 2 ~10 6 For example, it could be 10 2 10 3 10 4 10 5 Or 10 6 This applies to, but is not limited to, the listed values; other unlisted values ​​within this range also apply.

[0022] Preferably, the particle size of the montmorillonite is 0.5 to 5 μm, for example, it can be 0.5 μm, 1 μm, 1.3 μm, 2 μm, 3 μm or 5 μm, but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0023] Preferably, the concentration of aluminum hydroxide in the simulated water used for testing the ultrafiltration water purifier is 0.01 to 1 g / L, for example, it can be 0.01 g / L, 0.05 g / L, 0.1 g / L, 0.5 g / L, 0.8 g / L or 1 g / L, but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0024] Preferably, the concentration of aluminum sulfate in the simulated water used for testing the ultrafiltration water purifier is 0.01 to 1 g / L, for example, it can be 0.01 g / L, 0.05 g / L, 0.1 g / L, 0.5 g / L, 0.8 g / L or 1 g / L, but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0025] The molecular weight of humic acid, the concentration of montmorillonite, the concentration of aluminum hydroxide, and the concentration of aluminum sulfate in the simulated water used for testing the ultrafiltration water purifier described in this invention can be adjusted as needed to achieve realistic and accurate simulation of different water samples from various regions. For example, if the humic acid content in the tap water of a certain region is high, a higher molecular weight humic acid can be used when preparing the simulated water. Furthermore, the colloid content in the tap water of a certain region can be analyzed first, and a suitable ratio of montmorillonite, aluminum hydroxide, and aluminum sulfate can be selected for mixing to obtain a more accurate simulated tap water. Using these simulated water samples that accurately simulate real water samples to evaluate and test the filter element of the ultrafiltration water purifier ensures that the final ultrafiltration water purifier filter element can meet the filtration requirements of different regions and different water quality conditions, guaranteeing the drinking water safety of users.

[0026] Preferably, the turbidity of the simulated water used for testing the ultrafiltration water purifier is 1.0 to 2.0 NTU, for example, it can be 1.0 NTU, 1.2 NTU, 1.5 NTU, 1.7 NTU, 1.9 NTU or 2.0 NTU, but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0027] The turbidity of the simulated water used for testing the ultrafiltration water purifier described in this invention can be reasonably adjusted according to testing requirements, but it needs to be kept within the range of 1.0 to 2.0 NTU. This is because it is closer to the real light transmittance of daily drinking water and achieves a better simulation effect.

[0028] Secondly, the present invention also provides a method for preparing simulated water for testing an ultrafiltration water purifier as described in the first aspect, characterized in that the preparation method includes the following steps:

[0029] (1) Prepare bacterial solutions, humic acid stock solutions, montmorillonite stock solutions and aluminum hydroxide stock solutions respectively;

[0030] (2) Mix the test water, bacterial solution, humic acid stock solution, montmorillonite stock solution, aluminum hydroxide stock solution and aluminum sulfate, stir and dissolve to obtain the simulated water for the ultrafiltration water purifier test.

[0031] The method for preparing simulated water for ultrafiltration water purifier testing described in this invention is simple to operate. First, a stock solution of each substance is prepared, and then the water is prepared according to the water quality conditions of the water sample to be simulated. It does not require complex reaction conditions such as high temperature and high pressure and corresponding reaction equipment, and the preparation cost is low.

[0032] Preferably, the preparation method of the aluminum hydroxide stock solution in step (1) includes: after mixing aluminum sulfate solution and ammonia monohydrate solution, adjusting the pH to 5-6, for example, it can be 5, 5.2, 5.5, 5.7 or 6, but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0033] After stirring for 0.5 to 1 hour, such as 0.5h, 0.6h, 0.7h, 0.8h, 0.9h or 1 hour, but not limited to the listed values, other unlisted values ​​within this range are also applicable;

[0034] Drying at 70–80°C, such as 70°C, 72°C, 75°C, 78°C, 79°C, or 80°C, but not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0035] 10 to 12 hours, for example, 10h, 10.3h, 10.5h, 11h, 11.5h or 12h, but not limited to the listed values. Other unlisted values ​​within this range also apply.

[0036] The solution is filtered through a 0.2–0.45 μm filter membrane, such as 0.2 μm, 0.25 μm, 0.3 μm, 0.35 μm, 0.4 μm, or 0.45 μm, but not limited to the listed values; other unlisted values ​​within this range are also applicable. The resulting filtrate is an aluminum hydroxide stock solution.

[0037] In the preparation of aluminum hydroxide stock solution in this invention, after mixing aluminum sulfate solution and ammonia monohydrate solution, the pH is adjusted to 5-6 to form a colloid. Then, the solution is filtered through a 0.2-0.45 μm filter membrane, and the colloid enters the filtrate to form aluminum hydroxide stock solution.

[0038] Thirdly, the present invention also provides the use of simulated water for testing ultrafiltration water purifiers as described in the first aspect in evaluating the performance of ultrafiltration water purifier filter cartridges.

[0039] The simulated water used for testing ultrafiltration water purifiers described in this invention can realistically simulate different water qualities in different regions, enabling efficient evaluation and testing of the performance of ultrafiltration water purifier filter elements, and ensuring that the final ultrafiltration water purifier filter elements produced meet the usage requirements of various regions.

[0040] Compared with the prior art, the present invention has at least the following beneficial effects:

[0041] (1) The method for preparing simulated water for ultrafiltration water purifier testing provided by the present invention is simple to operate. The bacterial solution, humic acid stock solution, montmorillonite stock solution, aluminum hydroxide stock solution and aluminum sulfate are mixed with the test water to prepare simulated water containing colloids, organic matter and bacteria, which can accurately simulate the water quality of various tap waters.

[0042] (2) The simulated water for testing ultrafiltration water purifiers provided by the present invention can be used for performance evaluation testing of ultrafiltration water purifier filter cartridges without the need for on-site water sampling, thus reducing the cost of filter cartridge testing. Detailed Implementation

[0043] To facilitate understanding of the present invention, the following embodiments are provided. Those skilled in the art should understand that these embodiments are merely illustrative and should not be construed as limiting the scope of the invention.

[0044] The present invention will now be described in further detail. However, the examples described below are merely simplified examples of the present invention and do not represent or limit the scope of protection of the present invention. The scope of protection of the present invention is determined by the claims.

[0045] The water quality requirements for the test water described in the following examples and comparative examples are as follows: total hardness controlled at (250±20) mg / L; alkalinity controlled at (160±20) mg / L; pH controlled at 7 to 7.5.

[0046] The test water is prepared by adding spiked pure water (conductivity <10μS / cm, TDS <5mg / L) according to the following steps (taking the preparation of 100L of test water as an example):

[0047] a) Weigh out 61.56g of magnesium sulfate (MgSO4) . 7H2O) and 26.88g of anhydrous sodium bicarbonate (NaHCO3) were dissolved in a small amount of pure water respectively;

[0048] b) Add each of the above solutions separately to 100L of pure water. Stir well immediately after adding each solution, and then continue stirring for a while to ensure thorough mixing.

[0049] c) Take 5 mL to 10 mL of 5.2% sodium hypochlorite (NaClO) stock solution, dilute it with pure water to 1 L, then take 100 mL of this diluted solution and add it to the above 100 L of water, and stir immediately until well mixed.

[0050] d) Adjust the pH to the range of 7.0 to 7.5 using sodium hydroxide (NaOH) or hydrochloric acid (HCl);

[0051] e) The prepared test water should be stored in a light-proof, sealed container and should be prepared and used immediately. Test water prepared overnight should not be used. Note: All chemical reagents used are of analytical grade or equivalent purity.

[0052] Example 1

[0053] This embodiment provides a simulated water for testing an ultrafiltration water purifier, simulating tap water in area A of southern China. The simulated water for testing the ultrafiltration water purifier includes test water, Escherichia coli, humic acid, montmorillonite, aluminum hydroxide, and aluminum sulfate.

[0054] The montmorillonite has a particle size of 3 μm.

[0055] The concentration of E. coli in the simulated water used for testing the ultrafiltration water purifier was 2000 CFU / mL; the molecular weight of humic acid was 10. 5 The concentration of montmorillonite was 2 g / L; the concentration of aluminum hydroxide was 1 g / L; and the concentration of aluminum sulfate was 0.5 g / L.

[0056] The turbidity of the simulated water used in the ultrafiltration water purifier test was 2.0 NTU.

[0057] This embodiment also provides a method for preparing simulated water for testing ultrafiltration water purifiers that simulate tap water in southern region A, the preparation method comprising the following steps:

[0058] (1) Prepare bacterial solutions, humic acid stock solutions, montmorillonite stock solutions and aluminum hydroxide stock solutions respectively;

[0059] The preparation method of the aluminum hydroxide stock solution includes: mixing aluminum sulfate solution and ammonia monohydrate solution, adjusting the pH to 5.6, stirring for 1 hour, drying at 70°C for 12 hours, and filtering through a 0.45 μm filter membrane to obtain the filtrate as aluminum hydroxide stock solution.

[0060] (2) Mix the test water, bacterial solution, humic acid stock solution, montmorillonite stock solution, aluminum hydroxide stock solution and aluminum sulfate, stir and dissolve to obtain the simulated water for the ultrafiltration water purifier test that simulates tap water in South A.

[0061] In this embodiment, simulated water, actual tap water from southern region A, and test water were tested using the ultrafiltration water purifier filter cartridge, with the test water serving as a blank control group.

[0062] The specific testing method included the following steps: Three identical ultrafiltration machines were simultaneously circulated with water: one with tap water, one with simulated water, and one with test water. The inlet water pressure was 0.24 MPa for all machines, and the water flow rate was recorded every 1000 L. The flow rate results are shown in Table 1. When the total net water volume in the table was 0 L, the flow rates of the simulated water, tap water, and test water were 5.4 L / min because the initial flow rate used in the test was 5.4 L / min. The test water was used as a blank control group in the test.

[0063] Table 1

[0064] Total net water volume (L) Simulated water (L / min) Tap water (L / min) Test water volume (L / min) 0 5.4 5.4 5.4 1000 4.8 4.9 5.2 2000 4.1 4.1 5 3000 3.3 3.6 4.9 4000 2.4 2.5 4.7

[0065] As can be seen from Table 1:

[0066] As the total purified water volume increases, the flow rate of the simulated water used in the ultrafiltration water purifier test in this embodiment, which simulates tap water in area A of southern China, changes from 5.4 L / min to 2.4 L / min. This result is very close to the actual test result of tap water in area A of southern China, where the flow rate changes from 5.4 L / min to 2.5 L / min. This indicates that the composition and content of the simulated water are appropriate and can accurately simulate actual tap water.

[0067] Example 2

[0068] This embodiment provides a simulated water for testing an ultrafiltration water purifier, simulating tap water in area B in southern China. The simulated water for testing the ultrafiltration water purifier includes test water, Escherichia coli, humic acid, montmorillonite, aluminum hydroxide, and aluminum sulfate.

[0069] The montmorillonite has a particle size of 0.5 μm.

[0070] The concentration of E. coli in the simulated water used for testing the ultrafiltration water purifier was 1300 CFU / mL; the molecular weight of humic acid was 10. 6 The concentration of montmorillonite was 1.2 g / L; the concentration of aluminum hydroxide was 0.1 g / L; and the concentration of aluminum sulfate was 1 g / L.

[0071] The turbidity of the simulated water used in the ultrafiltration water purifier test was 1.5 NTU.

[0072] This embodiment also provides a method for preparing simulated water for testing the ultrafiltration water purifier that simulates tap water in area B of southern China. The preparation method includes the following steps:

[0073] (1) Prepare bacterial solutions, humic acid stock solutions, montmorillonite stock solutions and aluminum hydroxide stock solutions respectively;

[0074] The preparation method of the aluminum hydroxide stock solution includes: mixing aluminum sulfate solution and ammonia monohydrate solution, adjusting the pH to 5, stirring for 0.5 h, drying at 72 °C for 11 h, and filtering through a 0.2 μm filter membrane to obtain the filtrate as aluminum hydroxide stock solution.

[0075] (2) Mix the test water, bacterial solution, humic acid stock solution, montmorillonite stock solution, aluminum hydroxide stock solution and aluminum sulfate, stir and dissolve to obtain the simulated water for the ultrafiltration water purifier test that simulates tap water in southern region B.

[0076] In this embodiment, simulated water, actual tap water from Southern Region B, and test water were tested using the ultrafiltration water purifier filter cartridge. The test water served as a blank control group. The testing method was the same as in Example 1. The flow rate results are shown in Table 2.

[0077] Table 2

[0078] Total net water volume (L) Simulated water (L / min) Tap water (L / min) Test water volume (L / min) 0 5.4 5.4 5.4 1000 4.8 5 5.2 2000 4.3 4.3 5 3000 3.8 3.6 4.9 4000 2.7 2.9 4.7

[0079] As can be seen from Table 2:

[0080] As the total purified water volume increases, the flow rate of the simulated water used in the ultrafiltration water purifier test in this embodiment, which simulates tap water in Southern Region B, changes from 5.4 L / min to 2.7 L / min. This result is very close to the actual test result of tap water in Southern Region B, where the flow rate changes from 5.4 L / min to 2.9 L / min. This indicates that the composition and content of the simulated water are appropriate and can accurately simulate actual tap water.

[0081] Example 3

[0082] This embodiment provides a simulated water for testing an ultrafiltration water purifier, simulating tap water in region C of northern China. The simulated water for testing the ultrafiltration water purifier includes test water, Escherichia coli, humic acid, montmorillonite, aluminum hydroxide, and aluminum sulfate.

[0083] The montmorillonite has a particle size of 5 μm.

[0084] The concentration of E. coli in the simulated water used for testing the ultrafiltration water purifier was 1000 CFU / mL; the molecular weight of humic acid was 10. 2 The concentration of montmorillonite was 0.5 g / L; the concentration of aluminum hydroxide was 0.01 g / L; and the concentration of aluminum sulfate was 0.01 g / L.

[0085] The turbidity of the simulated water used in the ultrafiltration water purifier test was 1.0 NTU.

[0086] This embodiment also provides a method for preparing simulated water for testing the ultrafiltration water purifier that simulates tap water in region C of northern China. The preparation method includes the following steps:

[0087] (1) Prepare bacterial solutions, humic acid stock solutions, montmorillonite stock solutions and aluminum hydroxide stock solutions respectively;

[0088] The preparation method of the aluminum hydroxide stock solution includes: mixing aluminum sulfate solution and ammonia monohydrate solution, adjusting the pH to 6, stirring for 0.8 h, drying at 80 °C for 10 h, and filtering through a 0.3 μm filter membrane to obtain the filtrate as aluminum hydroxide stock solution;

[0089] (2) Mix the test water, bacterial solution, humic acid stock solution, montmorillonite stock solution, aluminum hydroxide stock solution and aluminum sulfate, stir and dissolve to obtain the simulated water for the ultrafiltration water purifier test that simulates tap water in northern region C.

[0090] In this embodiment, simulated water, actual tap water from location C in northern China, and test water were tested using the ultrafiltration water purifier filter cartridge, following the same testing method as in Example 1. The flow rate results are shown in Table 3.

[0091] Table 3

[0092] Total net water volume (L) Simulated water (L / min) Tap water (L / min) Test water volume (L / min) 0 5.4 5.4 5.4 1000 5 4.9 5.2 2000 4.5 4.4 5 3000 3.8 4 4.9 4000 3 3.3 4.7

[0093] As can be seen from Table 3:

[0094] As the total purified water volume increases, the flow rate of the simulated water used in the ultrafiltration water purifier test in this embodiment, which simulates tap water in Northern C region, changes from 5.4 L / min to 3 L / min. This result is very close to the actual test result of tap water in Northern C region, where the flow rate changes from 5.4 L / min to 3.3 L / min. This indicates that the composition and content of the simulated water are appropriate and can accurately simulate actual tap water.

[0095] Comparative Example 1

[0096] This comparative example provides simulated water for testing an ultrafiltration water purifier, simulating tap water in area A of southern China. Except for the concentration of montmorillonite, which is 0.2 g / L, the simulated water for testing the ultrafiltration water purifier is the same as that in Example 1.

[0097] Comparative Example 2

[0098] This comparative example provides simulated water for testing an ultrafiltration water purifier, simulating tap water in area A of southern China. Except for the concentration of montmorillonite, the simulated water for testing the ultrafiltration water purifier is the same as that in Example 1.

[0099] The low concentration of montmorillonite in Comparative Example 1 and the high concentration of montmorillonite in Comparative Example 2 both resulted in instability of the colloids in the simulated water used for the ultrafiltration water purifier test, making it impossible to accurately simulate actual tap water.

[0100] The applicant declares that the above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. A simulated water for testing an ultrafiltration water purifier, characterized in that, The simulated water used for testing the ultrafiltration water purifier includes test water, Escherichia coli, humic acid, montmorillonite, aluminum hydroxide, and aluminum sulfate; the concentration of montmorillonite in the simulated water used for testing the ultrafiltration water purifier is 0.5–2 g / L.

2. The simulated water for testing the ultrafiltration water purifier according to claim 1, characterized in that, The concentration of E. coli in the simulated water used for testing the ultrafiltration water purifier was 1000–2000 CFU / mL.

3. The simulated water for testing the ultrafiltration water purifier according to claim 1 or 2, characterized in that, The humic acid in the simulated water used for the ultrafiltration water purifier test had a molecular weight of 10. 2 ~10 6 .

4. The simulated water for testing the ultrafiltration water purifier according to any one of claims 1 to 3, characterized in that, The particle size of montmorillonite in the simulated water used for the ultrafiltration water purifier test was 0.5–5 μm.

5. The simulated water for testing the ultrafiltration water purifier according to any one of claims 1 to 4, characterized in that, The concentration of aluminum hydroxide in the simulated water used for the ultrafiltration water purifier test was 0.01–1 g / L.

6. The simulated water for testing the ultrafiltration water purifier according to any one of claims 1 to 5, characterized in that, The concentration of aluminum sulfate in the simulated water used for the ultrafiltration water purifier test was 0.01–1 g / L.

7. The simulated water for testing the ultrafiltration water purifier according to any one of claims 1 to 6, characterized in that, The turbidity of the simulated water used in the ultrafiltration water purifier test was 1.0 to 2.0 NTU.

8. A method for preparing simulated water for testing an ultrafiltration water purifier as described in any one of claims 1 to 7, characterized in that, The preparation method includes the following steps: (1) Prepare bacterial solutions, humic acid stock solutions, montmorillonite stock solutions and aluminum hydroxide stock solutions respectively; (2) Mix the test water, bacterial solution, humic acid stock solution, montmorillonite stock solution, aluminum hydroxide stock solution and aluminum sulfate, stir and dissolve to obtain the simulated water for the ultrafiltration water purifier test.

9. The preparation method according to claim 8, characterized in that, The preparation method of the aluminum hydroxide stock solution in step (1) includes: mixing aluminum sulfate solution and ammonia monohydrate solution, adjusting the pH to 5-6, stirring for 0.5-1h, drying at 70-80℃ for 10-12h, and filtering through a 0.2-0.45μm filter membrane to obtain the aluminum hydroxide stock solution.

10. The use of simulated water for testing an ultrafiltration water purifier as described in any one of claims 1 to 7 in evaluating the performance of the ultrafiltration water purifier filter element.