Composition for reverse osmosis scale inhibitor, reverse osmosis scale inhibitor as well as preparation method and application of reverse osmosis scale inhibitor

Abstract

The invention relates to the technical field of reverse osmosis membrane scale inhibition, and discloses a composition for a reverse osmosis scale inhibitor, the reverse osmosis scale inhibitor and a preparation method and application of the reverse osmosis scale inhibitor. The composition for the reverse osmosis scale inhibitor comprises the following components: polymaleic acid, a carboxylic sulfonate copolymer, a nitrogen-containing chelating agent, bacillus mucilaginosus fermentation liquor and sodium lichenate. Based on 100 parts by weight of the total weight of the composition, the content of the polymaleic acid is 25-35 parts by weight, the content of the carboxylic acid sulfonate copolymer is 25-35 parts by weight, the content of the nitrogen-containing chelating agent is 1-5 parts by weight, the content of the bacillus mucilaginosus fermentation liquor is 20-40 parts by weight, and the content of the sodium lichenate is 3-8 parts by weight. The reverse osmosis scale inhibitor disclosed by the invention has excellent inhibition capability on calcium carbonate scale, barium sulfate scale, calcium fluoride scale, strontium sulfate scale and calcium silicate scale, and the formation of the scale can be inhibited only by a small concentration.

Description

Technical Field

[0001] The present invention relates to the technical field of reverse osmosis membrane scale inhibition, and in particular to a reverse osmosis scale inhibitor composition, a reverse osmosis scale inhibitor, and a preparation method and application thereof. Background Art

[0002] Reverse osmosis (RO) equipment is widely used in water treatment projects, primarily for desalination. However, during operation, microparticles, colloids, or macromolecules in the influent interact physically and chemically with the RO membrane surface, adsorbing and depositing on the membrane surface or within the membrane pores to form scale. Once formed, scale will continue to grow unless treated, seriously affecting membrane flux and strength. Furthermore, scale accumulation can lead to corrosion in the pipelines, increasing cleaning and maintenance costs, and thus affecting performance and service life.

[0003] Pretreatment of the influent water of osmosis equipment is the mainstream method for preventing reverse osmosis membrane fouling. By adding scale inhibitors to the influent water, the formation of scale can be effectively reduced or inhibited, reducing the occurrence of membrane fouling. In addition, there are methods in the prior art that use microorganisms to degrade scale. For example, CN118581017A discloses a composite biological agent for circulating cooling water, characterized in that it includes the following biological agents by mass: 30-60 parts of Lactobacillus plantarum liquid, 10-30 parts of Lactobacillus schrenkiana liquid, 10-30 parts of Lactobacillus brevis liquid, 3-15 parts of Bacillus licheniformis liquid, and 10-20 parts of Nitrosomonas liquid. This circulating cooling water treatment agent can simultaneously degrade COD, ammonia nitrogen, total nitrogen, etc. in the circulating water, and also has the effect of scale inhibition. However, this composite biological agent uses live bacteria to achieve scale inhibition, which is prone to microbial growth; and microbial growth needs to be prevented in the prevention and control of reverse osmosis membrane pollution. Summary of the Invention

[0004] The purpose of the present invention is to solve the problem that the scale inhibition performance of the scale inhibitor in the prior art is single.

[0005] In order to achieve the above object, the first aspect of the present invention provides a composition for a reverse osmosis scale inhibitor, which comprises the following components:

[0006] Polymaleic acid, carboxylic acid sulfonate copolymer, nitrogen-containing chelating agent, Bacillus subtilis fermentation broth, sodium lichenate;

[0007] Based on 100 parts by weight of the total weight of the composition, the content of the polymaleic acid is 25-35 parts by weight, the content of the carboxylic acid sulfonate copolymer is 25-35 parts by weight, the content of the nitrogen-containing chelating agent is 1-5 parts by weight, the content of the Bacillus subtilis fermentation broth is 20-40 parts by weight, and the content of the sodium lichenate is 3-8 parts by weight;

[0008] The carboxylic acid sulfonate copolymer has a molecular weight of 4500-6000 g / mol and a density of ≥1.15 g / cm at 20°C. 3 , solid content is 42.0-44.0wt%; pH value is 3.8-4.6.

[0009] The second aspect of the present invention provides a method for preparing a reverse osmosis scale inhibitor, which is carried out using the components of the composition described in the first aspect, comprising:

[0010] (1) first mixing the polymaleic acid and carboxylic acid sulfonate copolymer with the Bacillus subtilis fermentation broth to obtain a mixture I;

[0011] (2) performing a second mixing of the mixture I and the nitrogen-containing chelating agent to obtain a mixture II;

[0012] (3) The mixture II is mixed with sodium lichenate for a third time to obtain a reverse osmosis scale inhibitor.

[0013] The third aspect of the present invention provides a reverse osmosis scale inhibitor prepared by the method described in the second aspect.

[0014] The fourth aspect of the present invention provides use of the reverse osmosis antiscalant described in the third aspect in antiscaling of reverse osmosis membranes.

[0015] The reverse osmosis scale inhibitor composition provided by the present invention exhibits excellent scale inhibition performance through the synergistic effects of components such as polymaleic acid, carboxylic acid sulfonate copolymer, nitrogen-containing chelating agent, Bacillus mucilaginosus fermentation broth, and sodium lichenate. It is capable of simultaneously inhibiting the scale of calcium carbonate, barium sulfate, calcium fluoride, strontium sulfate, and calcium silicate. Furthermore, during research, the inventors discovered that even better scale inhibition performance is achieved when the Bacillus mucilaginosus fermentation broth in the composition is used. DETAILED DESCRIPTION

[0016] The endpoints of the ranges and any values ​​disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoints of each range, the endpoints of each range and individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered to be specifically disclosed herein.

[0017] As mentioned above, the first aspect of the present invention provides a composition for a reverse osmosis scale inhibitor, the composition comprising the following components:

[0018] Polymaleic acid, carboxylic acid sulfonate copolymer, nitrogen-containing chelating agent, Bacillus subtilis fermentation broth, sodium lichenate;

[0019] Based on 100 parts by weight of the total weight of the composition, the content of the polymaleic acid is 25-35 parts by weight, the content of the carboxylic acid sulfonate copolymer is 25-35 parts by weight, the content of the nitrogen-containing chelating agent is 1-5 parts by weight, the content of the Bacillus subtilis fermentation broth is 20-40 parts by weight, and the content of the sodium lichenate is 3-8 parts by weight;

[0020] The carboxylic acid sulfonate copolymer has a molecular weight of 4500-6000 g / mol and a density of ≥1.15 g / cm at 20°C. 3 , solid content is 42.0-44.0wt%; pH value is 3.8-4.6.

[0021] Preferably, the carboxylic acid sulfonate copolymer is a carboxylic acid sulfonate copolymer with the brand name TH-2000 produced by Shandong Taihe Science and Technology Co., Ltd.

[0022] Preferably, the molecular weight of the polymaleic acid is 400-800 g / mol and the density at 20°C is 1.22-1.25 g / cm 3 , pH value is 2.0-3.0, bromine value ≤50mg / g, solid content ≥50wt%.

[0023] It should be noted that the pH value of the carboxylic acid sulfonate copolymer and polymaleic acid refers to the pH value of an aqueous solution containing 1 wt % of the carboxylic acid sulfonate copolymer and polymaleic acid.

[0024] More preferably, the polymaleic acid is polymaleic acid HPMA produced by Shandong Taihe Science and Technology Co., Ltd.

[0025] Preferably, the weight ratio of the Bacillus subtilis fermentation broth to the sodium lichenate is 6-9: 1. In this preferred embodiment, the inventors found that the obtained reverse osmosis antiscalant has better antiscaling performance.

[0026] Preferably, the Bacillus subtilis in the Bacillus subtilis fermentation broth is selected from the Bacillus subtilis produced by Shandong Yihao Biotechnology Co., Ltd.

[0027] Preferably, the nitrogen-containing chelating agent is at least one selected from diethylenetriaminepentaacetic acid, ethylenediaminetetraacetic acid, and aminotriacetic acid. The inventors have found that under this preferred condition, the obtained reverse osmosis antiscalant can further improve the scale inhibition performance against strontium salts and barium salts.

[0028] Preferably, the sodium lichenate is selected from the sodium lichenate produced by Shaanxi Mufan Biotechnology Co., Ltd.

[0029] According to a preferred embodiment, the Bacillus subtilis fermentation broth is prepared by a method comprising the following steps:

[0030] S1: contacting and sterilizing peptone, beef extract, and soil extract in sequence to obtain a fermentation medium;

[0031] S2: adding the Bacillus subtilis inoculum into the fermentation medium for fermentation, and centrifuging and filtering to obtain the Bacillus subtilis fermentation broth.

[0032] Preferably, the soil leachate is red soil leachate.

[0033] Preferably, the soil leachate is obtained by stirring and mixing red soil and water, and then filtering through double-layer gauze.

[0034] The present invention has no particular limitation on the stirring and mixing conditions, as long as the red soil and water can be mixed evenly.

[0035] Preferably, the water content of the red soil is ≤30 wt%.

[0036] Preferably, the amount of the red soil used is 20-30 g relative to 1 L of water.

[0037] Preferably, in step S1, relative to 1 L of the soil extract, the amount of the peptone is 4-6 g, and the amount of the beef extract is 4-6 g.

[0038] Preferably, the sterilization in step S1 is performed by moist heat sterilization.

[0039] Preferably, in step S1, the sterilization conditions include: sterilization temperature of 120-125°C, pressure of 103-115 kPa, and time of 20-40 min.

[0040] Preferably, in step S2, the fermentation conditions include: temperature of 36-37°C, rotation speed of 200-250 rpm, and time of 70-75 hours.

[0041] Preferably, in step S2, the total bacterial count in the fermented product is 1×10 8 The inventors found that under this preferred condition, the obtained reverse osmosis antiscalant can better decompose silicate minerals, thereby further improving the antiscaling performance of the reverse osmosis antiscalant.

[0042] Preferably, the centrifugal conditions include: a rotation speed of 9000-11000 rpm and a time of 4-7 min.

[0043] Preferably, the filtration is performed using a 0.2-0.25 μm filter membrane to filter the supernatant after centrifugation.

[0044] As mentioned above, the second aspect of the present invention provides a method for preparing a reverse osmosis scale inhibitor, which is carried out using the components of the composition described in the first aspect, comprising:

[0045] (1) first mixing the polymaleic acid and carboxylic acid sulfonate copolymer with the Bacillus subtilis fermentation broth to obtain a mixture I;

[0046] (2) performing a second mixing of the mixture I and the nitrogen-containing chelating agent to obtain a mixture II;

[0047] (3) The mixture II is mixed with sodium lichenate for a third time to obtain a reverse osmosis scale inhibitor.

[0048] It should be noted that the definitions and amounts of the polymaleic acid, carboxylic acid sulfonate copolymer, Bacillus subtilis fermentation broth, nitrogen-containing chelating agent, and sodium lichenate described in the present invention are the same as the definitions and contents of the corresponding components described in the first aspect, and will not be repeated here. Those skilled in the art should not understand this as a limitation to the present invention.

[0049] Preferably, the first mixing conditions include: temperature of 20-30° C., time of 60-120 min, and rotation speed of 150-250 rpm.

[0050] Preferably, the second mixing conditions include: temperature of 20-30° C., time of 60-120 min, and rotation speed of 150-250 rpm.

[0051] Preferably, the conditions for the third mixing include: temperature of 20-30° C., time of 60-120 min, and rotation speed of 40-60 rpm.

[0052] As mentioned above, the third aspect of the present invention provides a reverse osmosis scale inhibitor prepared by the method described in the second aspect.

[0053] As mentioned above, the fourth aspect of the present invention provides the use of the reverse osmosis antiscalant described in the third aspect in a reverse osmosis antiscalant.

[0054] The reverse osmosis scale inhibitor provided by the present invention has the following advantages:

[0055] (1) The reverse osmosis antiscalant of the present invention has a highly effective antiscaling performance and only requires a small amount of antiscalant to inhibit scale formation.

[0056] (2) The reverse osmosis scale inhibitor of the present invention has excellent scale inhibition ability and has excellent inhibition ability against calcium carbonate scale, barium sulfate scale, calcium fluoride scale, strontium sulfate scale and calcium silicate scale.

[0057] (3) The reverse osmosis scale inhibitor of the present invention can effectively slow down scaling and thus effectively extend the operating cycle of the equipment.

[0058] The present invention is described in detail below using examples. Unless otherwise specified, the instruments, reagents, and materials used in the following examples are all conventional instruments, reagents, and materials available in the prior art and can be obtained through regular commercial channels. The experimental methods and detection methods used in the following examples are all conventional experimental methods and detection methods available in the prior art, unless otherwise specified.

[0059] The main materials used in the examples and comparative examples are all commercially available, as detailed below.

[0060] Polymaleic acid: 400-800 g / mol, density at 20°C is 1.22-1.25 g / cm 3 , pH value is 2.0-3.0, bromine value ≤50 mg / g, solid content ≥50%, model HPMA, purchased from Shandong Taihe Science and Technology Co., Ltd.

[0061] Carboxylic acid sulfonate copolymer I: acrylic acid-acrylate-sulfonate copolymer, molecular weight 4500-6000 g / mol, density at 20°C 1.15 g / cm 3 , solid content is 42-44wt%; pH value is 3.8-4.6, model TH-2000, purchased from Shandong Taihe Science and Technology Co., Ltd.

[0062] Carboxylic acid sulfonate copolymer II: molecular weight 11000 g / mol, density at 20°C ≥ 1.10 g / cm 3 , solid content is 36.5-37.5wt%; pH value is 4.5-5.5, model KR-2100, purchased from Shandong Kairui Chemical Co., Ltd.

[0063] Nitrogen-containing chelating agent: diethylenetriaminepentaacetic acid, purchased from Shijiazhuang Jack Chemical Co., Ltd.

[0064] Sodium lichenate: purchased from Shaanxi Mufan Biotechnology Co., Ltd.

[0065] Bacillus subtilis: purchased from Shandong Yihao Biotechnology Co., Ltd., with a viable bacterial content of 5 billion CFU / g.

[0066] Bacillus licheniformis: purchased from Jinan Xinchenxu Chemical Co., Ltd.

[0067] Bacillus subtilis: purchased from Zhengzhou Zhongxi Biotechnology Co., Ltd.

[0068] Preparation Example 1: Preparation of Bacillus subtilis fermentation broth

[0069] S1: 25 g of red soil (water content 20 wt%) and 1 L of water were placed in a 2 L beaker and stirred, then filtered through double gauze to obtain a soil extract. 5 g of peptone, 5 g of beef extract, and 1 L of the soil extract were weighed and placed in a 2 L Erlenmeyer flask and sterilized by moist heat sterilization to obtain a fermentation medium.

[0070] The sterilization conditions are as follows: sterilization temperature is 121°C, pressure is 112 kPa, and time is 30 min;

[0071] S2: 1 g of Bacillus subtilis inoculum was added to the fermentation medium and fermented at 37°C and 220 rpm (shaker) for 72 h. The fermented product was then centrifuged at 10,000 rpm for 5 min. The supernatant was filtered through a 0.22 μm filter membrane to obtain the Bacillus subtilis fermentation broth.

[0072] Preparation Example 2: Preparation of Bacillus licheniformis fermentation broth

[0073] The preparation was carried out in a manner similar to that of Preparation Example 1, except that the mass of the Bacillus subtilis inoculant was replaced by the Bacillus licheniformis inoculant; the remaining conditions were the same as those of Preparation Example 1.

[0074] Preparation Example 3: Preparation of Bacillus subtilis fermentation broth

[0075] The preparation was carried out in a manner similar to that of Preparation Example 1, except that the mass of the Bacillus subtilis inoculant was replaced by that of the Bacillus subtilis inoculant; the remaining conditions were the same as those of Preparation Example 1.

[0076] Example 1

[0077] This example is used to illustrate that the composition for the reverse osmosis scale inhibitor of the present invention is prepared according to the formula and process parameters in Table 1 and the following method;

[0078] (1) first mixing the polymaleic acid and carboxylic acid sulfonate copolymer with the Bacillus subtilis fermentation broth to obtain a mixture I;

[0079] (2) performing a second mixing of the mixture I and the nitrogen-containing chelating agent to obtain a mixture II;

[0080] (3) The mixture II is mixed with sodium lichenate for a third time to obtain a reverse osmosis scale inhibitor.

[0081] The remaining examples were carried out using a method similar to that of Example 1, except that the composition formulations and process parameters were different, as shown in Table 1.

[0082] Table 1 (each weight portion represents 1g)

[0083] Example 1 Example 2 Example 3 Example 4 Polymaleic acid Dosage / weight 30 35 30 Same as Example 1 Carboxylic acid sulfonate copolymer I Dosage / weight 30 26 35 Same as Example 1 Nitrogen-containing chelating agents Dosage / weight 1 5 5 Same as Example 1 Bacillus subtilis fermentation broth Dosage / weight 34 30 27 36 Sodium lichenate Dosage / weight 5 4 3 3 First Mix Stirring speed (rpm) 220 250 Same as Example 1 Same as Example 1 Temperature (℃) 25 20 Same as Example 1 Same as Example 1 Time (min) 90 60 Same as Example 1 Same as Example 1 Second Mix Stirring speed (rpm) 200 250 Same as Example 1 Same as Example 1 Temperature (℃) 25 20 Same as Example 1 Same as Example 1 Time (min) 90 60 Same as Example 1 Same as Example 1 Third Mix Stirring speed (rpm) 50 60 Same as Example 1 Same as Example 1 Temperature (℃) 25 20 Same as Example 1 Same as Example 1 Time (min) 120 90 Same as Example 1 Same as Example 1

[0084] Comparative Example 1

[0085] The method is similar to that of Example 1, except that the carboxylic acid sulfonate copolymer II is used in place of the carboxylic acid sulfonate copolymer I in Example 1 with an equal weight;

[0086] The remaining steps are the same as those in Example 1; and a reverse osmosis scale inhibitor is obtained.

[0087] Comparative Example 2

[0088] A method similar to that of Example 1 was used, except that an equal weight of Bacillus licheniformis fermentation broth was used to replace the Bacillus mucilaginosus fermentation broth in Example 1;

[0089] The remaining steps are the same as those in Example 1; and a reverse osmosis scale inhibitor is obtained.

[0090] Comparative Example 3

[0091] A method similar to that of Example 1 was used, except that an equal weight of Bacillus subtilis fermentation broth was used to replace the Bacillus subtilis fermentation broth in Example 1;

[0092] The remaining steps are the same as those in Example 1; and a reverse osmosis scale inhibitor is obtained.

[0093] Comparative Example 4

[0094] A method similar to Example 1 was used, except that the amount of Bacillus subtilis fermentation broth used was 42 parts by weight and the amount of sodium lichenate used was 7 parts by weight;

[0095] The remaining steps are the same as those in Example 1; and a reverse osmosis scale inhibitor is obtained.

[0096] Comparative Example 5

[0097] The method was similar to that of Example 1, except that the amount of polymaleic acid used was 20 parts by weight and the amount of carboxylic acid sulfonate copolymer used was 40 parts by weight;

[0098] The remaining steps are the same as those in Example 1; and a reverse osmosis scale inhibitor is obtained.

[0099] Test Case

[0100] The scale inhibition performance of the reverse osmosis scale inhibitor prepared in the example was tested with reference to the test guide for performance evaluation of reverse osmosis scale inhibitors for thermal power plants (DL / T 1261-2013).

[0101] Principle of the method: A test solution is prepared by mixing test water containing a certain amount of scale-forming ions with a reverse osmosis scale inhibitor. Under simulated concentration conditions, the precipitation of scale-forming ions is accelerated. The conductivity change and the amount of titrant consumed at the initial scaling conditions are measured to calculate the supersaturation value of the scale-forming compounds.

[0102] Supersaturation S calculation formula: S=(C a ×C b ) / K sp

[0103] C a =(C1×V1) / V

[0104] C b =(C2×V2) / V

[0105] C a - The concentration of calcium, barium or strontium ions in the solution before the conductivity no longer increases.

[0106] C b - The concentration of carbonate ions, sulfate ions, fluoride ions or silicate ions in the solution before the conductivity no longer increases.

[0107] C1 - the concentration of the calcium chloride, barium chloride or strontium nitrate reagent used.

[0108] C2 - concentration of the sodium carbonate, sodium sulfate, potassium fluoride or sodium silicate reagent used.

[0109] V1 - the volume of calcium chloride, barium chloride or strontium nitrate reagent added before the test.

[0110] V2 - the volume of sodium carbonate, sodium sulfate, potassium fluoride or sodium silicate reagent added in the test.

[0111] V - total test volume.

[0112] K sp ——At 25℃, solubility product constant: calcium carbonate K sp =4.8×10 -9 ; Barium sulfate K sp =1.1×10 -10 Calcium fluoride K sp =4.0×10 -11 ; Strontium sulfate K sp =3.44×10 -7 Calcium silicate K sp =1.14×10 -8 .

[0113] The specific test methods are as follows:

[0114] 1. Determination of calcium carbonate resistance performance

[0115] (1) Prepare the test solution: 200 mL of 0.005 mol / L calcium chloride solution containing 2 mg / L of scale inhibitor, and keep it in a water bath at 25°C.

[0116] (2) Titration steps: Place a conductivity electrode and a magnetic stirring rotor into the test solution and start stirring (stirring speed 50 r / min). After the reading stabilizes, record the initial conductivity reading and titrate with 0.5 mol / L sodium carbonate titrant, adding 0.05 mL each time. After the conductivity value stabilizes for 1 min, continue adding.

[0117] (3) End point determination: When the conductivity of the test solution does not increase with the volume of the titrant and the test solution begins to become turbid, continue adding the titrant until the conductivity value cannot be stabilized within 1 minute and begins to decrease. The test reaches the endpoint and the volume of the titrant consumed before the conductivity begins to decrease is the titration result.

[0118] 2. Performance determination of barium sulfate

[0119] (1) Prepare the test solution: 200 mL of 0.5 mmol / L calcium chloride solution containing 2 mg / L of scale inhibitor, and keep it in a water bath at 25°C.

[0120] (2) Titration step: The titration step is the same as step (2) of the method for determining the calcium carbonate inhibition performance, except that the titrant is 0.05 mol / L sodium sulfate.

[0121] (3) End point determination: the same as step (3) of the method for determining calcium carbonate inhibition performance.

[0122] 3. Performance determination of calcium fluoride

[0123] (1) Prepare the test solution: 200 mL of 0.005 mol / L calcium chloride solution containing 2 mg / L of scale inhibitor, and keep it in a water bath at 25°C.

[0124] (2) Titration step: The titration step is the same as step (2) of the method for determining the calcium carbonate inhibition performance, except that the titrant is 0.2 mol / L potassium fluoride.

[0125] (3) End point determination: the same as step (3) of the method for determining calcium carbonate inhibition performance.

[0126] 4. Performance determination of strontium sulfate

[0127] (1) Prepare the test solution: 200 mL of 0.05 mol / L strontium nitrate solution containing 2 mg / L of scale inhibitor, and keep it in a water bath at 25°C.

[0128] (2) Titration step: The same as step (2) of the method for determining the calcium carbonate inhibition performance, except that the titrant is 1.0 mol / L sodium sulfate.

[0129] (3) End point determination: the same as step (3) of the method for determining calcium carbonate inhibition performance.

[0130] 5. Performance determination of calcium silicate

[0131] (1) Prepare the test solution: 200 mL of 0.005 mol / L calcium chloride solution containing 2 mg / L of scale inhibitor, and keep it in a water bath at 25°C.

[0132] (2) Titration step: The same as step (2) of the method for determining the calcium carbonate inhibition performance, except that the titrant is 0.001 mol / L sodium silicate.

[0133] (3) End point determination: the same as step (3) of the method for determining calcium carbonate inhibition performance.

[0134] The test results are shown in Table 2.

[0135] Table 2

[0136]

[0137] It can be seen from the results in the above table that the reverse osmosis scale inhibitor provided by the present invention has excellent scale inhibition performance for calcium carbonate, barium sulfate, calcium fluoride, strontium sulfate and calcium silicate.

[0138] The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, various simple variations of the technical solution of the present invention may be made, including combining the various technical features in any other appropriate manner. These simple variations and combinations should also be regarded as disclosed in the present invention and fall within the scope of protection of the present invention.

Claims

1. A composition for a reverse osmosis scale inhibitor, characterized in that: The reverse osmosis antiscalant composition comprises the following components: Polymaleic acid, carboxylic acid sulfonate copolymer, nitrogen-containing chelating agent, Bacillus subtilis fermentation broth, sodium lichenate; Based on 100 parts by weight of the total weight of the composition, the content of the polymaleic acid is 25-35 parts by weight, the content of the carboxylic acid sulfonate copolymer is 25-35 parts by weight, the content of the nitrogen-containing chelating agent is 1-5 parts by weight, the content of the Bacillus subtilis fermentation broth is 20-40 parts by weight, and the content of the sodium lichenate is 3-8 parts by weight; The carboxylic acid sulfonate copolymer has a molecular weight of 4500-6000 g / mol and a density of ≥1.15 g / cm at 20°C. 3 , solid content is 42.0-44.0wt%; pH value is 3.8-4.

6.

2. The reverse osmosis antiscalant composition according to claim 1, characterized in that: The molecular weight of the polymaleic acid is 400-800 g / mol, and the density at 20°C is 1.22-1.25 g / cm 3 , pH value is 2.0-3.0, bromine value ≤50mg / g, solid content ≥50wt%.

3. The reverse osmosis antiscalant composition according to claim 1 or 2, characterized in that: The weight ratio of the Bacillus subtilis fermentation broth to the sodium lichenate is 6-9:

1.

4. The reverse osmosis antiscalant composition according to claim 1 or 2, characterized in that: The nitrogen-containing chelating agent is selected from at least one of diethylenetriaminepentaacetic acid, ethylenediaminetetraacetic acid, and aminotriacetic acid.

5. The reverse osmosis antiscalant composition according to claim 1 or 2, characterized in that: The Bacillus subtilis fermentation broth is prepared by a method comprising the following steps: S1: contacting and sterilizing peptone, beef extract, and soil extract in sequence to obtain a fermentation medium; S2: adding the Bacillus subtilis inoculum into the fermentation medium for fermentation, and centrifuging and filtering to obtain the Bacillus subtilis fermentation broth.

6. The reverse osmosis antiscalant composition according to claim 5, characterized in that: In step S2, the fermentation conditions include: temperature of 36-37°C, rotation speed of 200-250 rpm, and time of 70-75 hours.

7. A method for preparing a reverse osmosis scale inhibitor, characterized in that: The method is carried out using the components of the composition according to any one of claims 1 to 6, comprising: (1) first mixing the polymaleic acid and carboxylic acid sulfonate copolymer with the Bacillus subtilis fermentation broth to obtain a mixture I; (2) performing a second mixing of the mixture I and the nitrogen-containing chelating agent to obtain a mixture II; (3) The mixture II is mixed with sodium lichenate for a third time to obtain a reverse osmosis scale inhibitor.

8. The method according to claim 7, characterized in that The first mixing conditions include: temperature of 20-30° C., time of 60-120 min, and rotation speed of 150-250 rpm; and / or The second mixing conditions include: temperature of 20-30°C, time of 60-120 min, and rotation speed of 150-250 rpm; and / or The conditions of the third mixing include: temperature of 20-30° C., time of 60-120 min, and rotation speed of 40-60 rpm.

9. A reverse osmosis antiscalant prepared by the method according to claim 7 or 8.

10. Use of the reverse osmosis antiscalant according to claim 9 in reverse osmosis membrane scale inhibition.

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