CN114159975A - Preparation method of reverse osmosis membrane silica scale inhibitor and scale inhibitor - Google Patents
Preparation method of reverse osmosis membrane silica scale inhibitor and scale inhibitor Download PDFInfo
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- CN114159975A CN114159975A CN202111444966.0A CN202111444966A CN114159975A CN 114159975 A CN114159975 A CN 114159975A CN 202111444966 A CN202111444966 A CN 202111444966A CN 114159975 A CN114159975 A CN 114159975A
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- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D65/00—Accessories or auxiliary operations, in general, for separation processes or apparatus using semi-permeable membranes
- B01D65/02—Membrane cleaning or sterilisation ; Membrane regeneration
- B01D65/06—Membrane cleaning or sterilisation ; Membrane regeneration with special washing compositions
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D65/00—Accessories or auxiliary operations, in general, for separation processes or apparatus using semi-permeable membranes
- B01D65/08—Prevention of membrane fouling or of concentration polarisation
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2321/00—Details relating to membrane cleaning, regeneration, sterilization or to the prevention of fouling
- B01D2321/16—Use of chemical agents
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Abstract
The invention discloses a preparation method of a reverse osmosis membrane silica scale inhibitor and the scale inhibitor prepared by the preparation method, wherein the preparation method comprises the following steps: mixing and stirring carboxylic acid polymer and sulfonic acid polymer for 10-20min, and heating the mixed solution to 40-50 ℃; then adding hydroxyl compound, stirring for 30-40min at constant temperature of 40-50 deg.C until completely dissolving; then adding quaternary ammonium salt polymer, stirring for 10-20min at the constant temperature of 40-50 ℃, and cooling to obtain scale inhibitor A; and then introducing micro-nano bubbles into the scale inhibitor A to obtain a scale inhibitor B. The silica scale inhibitor has stable property and can effectively prevent SiO2Scale and silicate scale are generated, the scale inhibition effect is good, and the service life of the reverse osmosis membrane can be effectively prolonged when the scale inhibitor is used in a reverse osmosis system; meanwhile, the silica scale inhibitor does not contain phosphorus, and is environment-friendly and safe.
Description
Technical Field
The invention relates to the technical field of water treatment agents, and particularly relates to a preparation method of a reverse osmosis membrane silica scale inhibitor and the scale inhibitor.
Background
Reverse osmosis is a membrane separation operation that separates a solvent from a solution using a pressure difference as a driving force, and has advantages of low energy consumption, high efficiency, and the like. At present, reverse osmosis has been widely applied in seawater desalination, industrial wastewater treatment and landfill leachate treatment.
In the process of membrane filtration, particles, colloidal particles or solute macromolecules and the like in water are adsorbed, deposited and scaled on the surface of the membrane or in membrane pores due to the physical and chemical action or mechanical action of the pre-membrane, so that the membrane pore size is reduced or blocked, and the performance of the membrane is reduced. The flux of the membrane is reduced due to the scaling of the membrane, the energy consumption is increased, the membrane needs to be cleaned frequently, and the reverse osmosis system can not work normally or even be damaged when the scaling is serious. In order to prevent and reduce scaling, adding scale inhibitors in the reverse osmosis process is the most common and efficient method.
The silica scale is mainly SiO2The scale and silicate scale belong to amorphous scale, and are common scale which is difficult to clean and has large membrane damage. Research shows that when the content of the dissolved silicon in the solution is lower than 10mg/L, the reverse osmosis system does not scale. In order to reduce the deposition of silica scale, scale inhibitors are generally added during reverse osmosis. However, the existing scale inhibitor has poor scale inhibition effect, contains most phosphide and is not beneficial to environmental protection.
In view of the above, the inventor of the present application invented a preparation method of a reverse osmosis membrane silica scale inhibitor and a scale inhibitor.
Disclosure of Invention
The invention aims to provide a preparation method of a reverse osmosis membrane silica scale inhibitor with good silica scale inhibition effect and environmental protection and the scale inhibitor.
In order to achieve the purpose, the invention adopts the following technical scheme: a preparation method of a reverse osmosis membrane silica scale inhibitor comprises the following steps:
s1: mixing and stirring carboxylic acid polymer and sulfonic acid polymer for 10-20min, and heating the mixed solution to 40-50 ℃;
s2: adding a hydroxyl compound into the solution obtained in the step S1, and stirring for 30-40min at a constant temperature of 40-50 ℃ until the hydroxyl compound is completely dissolved;
s3: adding the quaternary ammonium salt polymer into the solution obtained in the step S2, stirring for 10-20min at the constant temperature of 40-50 ℃, and cooling to obtain a scale inhibitor A;
s4: and introducing the micro-nano bubbles into the scale inhibitor A to obtain a scale inhibitor B.
Further, in step S1, the carboxylic acid polymer is PESA, and the mass percentage concentration of the PESA is 30 to 50% and the degree of polymerization is 5 to 10.
Further, in step S1, the sulfonic acid polymer is AA/AMPS, and the mass percentage concentration of the AA/AMPS is 30-40%.
Further, in step S2: the hydroxyl compound is boric acid, gallic acid or citric acid.
Further, in step S3: the quaternary ammonium salt polymer is PEI, and the mass percentage concentration of the PEI is 99%.
Further, in step S4, the diameter of the micro-nano bubble is smaller than 50 microns.
Further, in step S4, the volume ratio of the micro-nano bubbles to the scale inhibitor a is 2: 5.
The reverse osmosis membrane silica scale inhibitor prepared by the method comprises a carboxylic acid polymer, a sulfonic acid polymer, a hydroxyl compound and a quaternary ammonium salt polymer, wherein the components in percentage by mass are as follows:
the carboxylic acid polymer is PESA, and accounts for 15-25%;
the sulfonic acid polymer is AA/AMPS, and accounts for 15-25% of the total weight;
the quaternary ammonium salt polymer is PEI and accounts for 45-55%;
the hydroxyl compound is boric acid and accounts for 5-15% of the total weight of the composition.
After adopting the technical scheme, compared with the prior art, the invention has the following advantages:
the silica scale inhibitor has stable property and can effectively prevent SiO2Scale and silicate scale are generated, the scale inhibition effect is good, and the service life of the reverse osmosis membrane can be effectively prolonged when the scale inhibitor is used in a reverse osmosis system; meanwhile, the silicon scale inhibitor of the invention does not contain phosphorus and contains no ringAnd (4) safety is guaranteed.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
The invention discloses a preparation method of a reverse osmosis membrane silica scale inhibitor and the scale inhibitor, which comprises the following steps:
s1: mixing and stirring carboxylic acid polymer and sulfonic acid polymer for 10-20min, and heating the mixed solution to 40-50 ℃;
wherein, the carboxylic acid polymer is PESA (polyepoxysuccinic acid) preferably, and the PESA is a light yellow solution, the mass percentage concentration of the PESA is 30-50%, and the polymerization degree is 5-10. Of course, other materials may be selected for the carboxylic acid polymer, such as: HPMA (polymaleic acid), PASP (polyaspartic acid), PAA (polyacrylic acid), and the like.
The sulfonic acid polymer is AA/AMPS (acrylic acid-2-acrylamide-2-methyl propanesulfonic acid), and the mass percentage concentration of the AA/AMPS is 30-40%. Of course, the sulfonic acid polymer can also be replaced by other substances, such as: maleic anhydride-sulfonated styrene copolymer, acrylic acid-hydroxypropyl acrylate-AMPS terpolymer, etc.
S2: adding a hydroxyl compound into the solution obtained in the step S1, and stirring for 30-40min at a constant temperature of 40-50 ℃ until the hydroxyl compound is completely dissolved;
wherein the hydroxyl compound is preferably boric acid as a white powdery solid. Of course, the hydroxy compound may be gallic acid or citric acid.
S3: adding the quaternary ammonium salt polymer into the solution obtained in the step S2, stirring for 10-20min at the constant temperature of 40-50 ℃, and cooling to obtain a scale inhibitor A;
wherein the quaternary ammonium salt polymer is PEI, and the mass percentage concentration of the PEI is 99%.
S4: and introducing the micro-nano bubbles into the scale inhibitor A to obtain a scale inhibitor B.
Wherein the diameter of the micro-nano bubbles is less than 50 microns. The volume ratio of the micro-nano bubbles to the scale inhibitor A is 2: 5. The micro-nano bubbles are generated by a nano bubble generator and are introduced with a scale inhibitor A.
The invention also discloses a reverse osmosis membrane silica scale inhibitor prepared by the preparation method, which comprises a carboxylic acid polymer, a sulfonic acid polymer, a hydroxyl compound and a quaternary ammonium salt polymer, wherein the components in percentage by mass are as follows:
the carboxylic acid polymer is PESA, and accounts for 15-25%;
the sulfonic acid polymer is AA/AMPS, and accounts for 15-25% of the total weight;
the quaternary ammonium salt polymer is PEI and accounts for 45-55%;
the hydroxyl compound is boric acid and accounts for 5-15% of the total weight of the composition.
Among them, PESA contains a carboxyl group. The carboxyl is a hydrophilic group, has good water solubility, and can play a role in chelating metal cations in liquid and lattice distortion; can destroy the crystal form of the scale and disperse the formed scale, thereby increasing the solubility of metal ions in the solution.
AA/AMPS contains sulfonic acid groups. The sulfonic group has strong water solubility, is easy to dissolve in a polar solvent, is a strong polar group, and can enhance the dispersing capacity of the scale inhibitor to scale. -SO3Two pi bonds on H and 3 strong electronegative oxygen share one negative charge, so that the stability of the scale inhibitor is good, and the scale inhibitor is insensitive to external cations, and the temperature resistance and the salt resistance of the scale inhibitor are improved.
PEI is a cationic polymer which can adsorb and chelate anions and negatively charged particles in water, such as silicate ions and silica particles, thereby effectively preventing the precipitation of silica scale.
The boronic acid contains a hydroxyl group. The hydrophilic silicate scale inhibitor has good hydrophilicity, can increase the solubility of molecules in water, contains lone pair electrons, can coordinate with metal ions, and chelates the metal ions in a solution, thereby reducing the formation of silicate scale.
Particularly, the micro-nano bubbles are micro-bubbles with the diameter less than 50 microns and are not sensitive to the pH value of the aqueous solution. The water-soluble polymer is introduced into a scale inhibitor A, and one important function of the water-soluble polymer is as a dispersant. In a neutral solution with the pH value of more than 5 or 6, the silicon dioxide and the micro-nano bubbles are negatively charged, the zeta potentials (shear plane potentials) of the silicon dioxide and the micro-nano bubbles are large enough in absolute value, the silicon dioxide scaling can be inhibited through the interaction of the stable particles and the nano bubbles, the silicon dioxide polymerization and the silicon dioxide colloid agglomeration can be inhibited, and the formation of silica scale can be effectively prevented.
Examples
In the embodiment, the scale inhibitor comprises the following components in percentage by mass: PESA 20%, AA/AMPS 20%, PEI 50% and boric acid 10%. The volume ratio of gas to liquid is 2: 5. The scale inhibitor A and the scale inhibitor B are respectively prepared according to the proportion by adopting the preparation method, and scale inhibition experiments are respectively carried out on the scale inhibitor A and the scale inhibitor B.
Experiment 1: static scale inhibition test experiment
1) Static barrier SiO2Scale experiments
The experimental method comprises the following steps: the weight concentration of the mixture is 500mg/L (the concentration is SiO) in a polyethylene bottle2Calculated) Na2SiO3Adding a certain amount of scale inhibitor A or scale inhibitor B into the solution; the pH of the solution was adjusted to 7.0. + -. 0.1 while a blank experiment was performed. Placing the water sample in a constant temperature water tank at 40 deg.C, collecting supernatant every 4h within 48h, filtering with 0.45 μm filter membrane, diluting by a certain multiple, and determining SiO in the water sample by molybdenum blue colorimetry2And (4) calculating the scale inhibition rate.
2): static silicate scale inhibition experiment
The experimental method comprises the following steps: the weight concentration of the mixture is 500mg/L (the concentration is SiO) in a polyethylene bottle2Calculated) Na2SiO3Adding a certain amount of scale inhibitor A or B into the solution, adjusting the pH of the solution to about 7.5, and adding a certain amount of CaCl2Solutions (in CaCO concentration)3Meter) to make Ca in the solution2+The mass concentration was 500mg/L, and a blank experiment was conducted. Placing the water sample in a constant temperature water tank at 40 deg.C, collecting supernatant every 4h within 48h, filtering with 0.45 μm filter membrane, diluting by a certain multiple, and determining SiO in the water sample by molybdenum blue colorimetry2And (4) content. Calculating resistanceThe fouling rate.
The scale inhibition rate calculation formula is as follows:
in the formula: rho is the mass concentration of silicon dioxide in the original solution, mg/L; rho0The mass concentration of silicon dioxide in the blank group solution is mg/L; rho1The mass concentration of silicon dioxide added into the solution of the scale inhibitor is mg/L.
The results of the scale inhibition experiments are shown in the following table.
TABLE 1 static barrier SiO2Results of scale testing experiments
TABLE 2 static silicate scale resistance test results
As can be seen from the test results in tables 1 and 2: the scale inhibitor A and the scale inhibitor B both have good silicon scale inhibition effect, and the scale inhibition effect of the scale inhibitor B is superior to that of the scale inhibitor A, namely, micro-nano bubbles are introduced into the scale inhibitor A to have a synergistic scale inhibition effect with the scale inhibitor A, so that the formation of silicon scale is inhibited.
Experiment 2: practical case
The water quality of certain industrial wastewater is shown in the following Table 3 according to the static SiO resistance2The scale inhibition rate of the scale inhibitor A and the scale inhibitor B is measured by a scale experiment method and a static silicate scale inhibition experiment method (the adding amount of the scale inhibitor is 10 mg/L). The results were: scale inhibitor A inhibits SiO2The scale inhibition rates of the scale and the silicate scale are respectively 80% and 85%; scale inhibitor B inhibits SiO2Scale and silicate scale inhibitionThe fouling rate was 92%, 96%. Therefore, the scale inhibitor A and the scale inhibitor B both have better silicon scale inhibition effect, and the scale inhibition effect of the scale inhibitor B is better than that of the scale inhibitor A.
TABLE 3 quality of certain industrial wastewater
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.
Claims (9)
1. A preparation method of a reverse osmosis membrane silica scale inhibitor is characterized by comprising the following steps: the method comprises the following steps:
s1: mixing and stirring carboxylic acid polymer and sulfonic acid polymer for 10-20min, and heating the mixed solution to 40-50 ℃;
s2: adding a hydroxyl compound into the solution obtained in the step S1, and stirring for 30-40min at a constant temperature of 40-50 ℃ until the hydroxyl compound is completely dissolved;
s3: adding the quaternary ammonium salt polymer into the solution obtained in the step S2, stirring for 10-20min at the constant temperature of 40-50 ℃, and cooling to obtain a scale inhibitor A;
s4: and introducing the micro-nano bubbles into the scale inhibitor A to obtain a scale inhibitor B.
2. The preparation method of the reverse osmosis membrane silica scale inhibitor according to claim 1, which is characterized in that: in step S1, the carboxylic acid polymer is PESA, and the mass percentage concentration of the PESA is 30 to 50% and the degree of polymerization is 5 to 10.
3. The preparation method of the reverse osmosis membrane silica scale inhibitor according to claim 1, which is characterized in that: in step S1, the sulfonic acid polymer is AA/AMPS, and the mass percentage concentration of the AA/AMPS is 30-40%.
4. The preparation method of the reverse osmosis membrane silica scale inhibitor according to claim 1, which is characterized in that: in step S2: the hydroxyl compound is boric acid, gallic acid or citric acid.
5. The preparation method of the reverse osmosis membrane silica scale inhibitor according to claim 1, which is characterized in that: in step S3: the quaternary ammonium salt polymer is PEI, and the mass percentage concentration of the PEI is 99%.
6. The preparation method of the reverse osmosis membrane silica scale inhibitor according to claim 1, which is characterized in that: in step S4, the diameter of the micro-nano bubbles is smaller than 50 microns.
7. The method for preparing the scale inhibitor for reverse osmosis membrane silica scale according to claim 1 or 6, wherein the method comprises the following steps: in step S4, the volume ratio of the micro-nano bubbles to the scale inhibitor a is 2: 5.
8. A reverse osmosis membrane scale inhibitor prepared by the method of any one of claims 1 to 7.
9. The scale inhibitor for reverse osmosis membrane silica scale according to claim 8, wherein: the adhesive comprises a carboxylic acid polymer, a sulfonic acid polymer, a hydroxyl compound and a quaternary ammonium salt polymer, wherein the components in percentage by mass are as follows:
the carboxylic acid polymer is PESA, and accounts for 15-25%;
the sulfonic acid polymer is AA/AMPS, and accounts for 15-25% of the total weight;
the quaternary ammonium salt polymer is PEI and accounts for 45-55%;
the hydroxyl compound is boric acid and accounts for 5-15% of the total weight of the composition.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114956356A (en) * | 2022-06-09 | 2022-08-30 | 长江师范学院 | Mixed scale inhibitor and preparation method and application thereof |
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| US4584104A (en) * | 1984-06-29 | 1986-04-22 | Nalco Chemical Company | Silica inhibition: prevention of silica deposition by boric acid/orthorborate ion |
| CN101948189A (en) * | 2010-09-02 | 2011-01-19 | 蓝星环境工程有限公司 | Non-phosphorus reverse osmosis membrane scale inhibitor and preparation method thereof |
| JP2011161409A (en) * | 2010-02-15 | 2011-08-25 | Panasonic Environmental Systems & Engineering Co Ltd | Apparatus for producing pure water |
| CN107362691A (en) * | 2017-06-22 | 2017-11-21 | 山东英联化学科技有限公司 | Seawater desalination reverse osmosis film green research of non-phosphorus scale inhibitor and preparation method thereof |
| US20190118142A1 (en) * | 2017-08-29 | 2019-04-25 | The Regents Of The University Of California | Methods, systems, and compositions for delivery of nanobubbles in water treatment systems |
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- 2021-11-30 CN CN202111444966.0A patent/CN114159975A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4584104A (en) * | 1984-06-29 | 1986-04-22 | Nalco Chemical Company | Silica inhibition: prevention of silica deposition by boric acid/orthorborate ion |
| JP2011161409A (en) * | 2010-02-15 | 2011-08-25 | Panasonic Environmental Systems & Engineering Co Ltd | Apparatus for producing pure water |
| CN101948189A (en) * | 2010-09-02 | 2011-01-19 | 蓝星环境工程有限公司 | Non-phosphorus reverse osmosis membrane scale inhibitor and preparation method thereof |
| CN107362691A (en) * | 2017-06-22 | 2017-11-21 | 山东英联化学科技有限公司 | Seawater desalination reverse osmosis film green research of non-phosphorus scale inhibitor and preparation method thereof |
| US20190118142A1 (en) * | 2017-08-29 | 2019-04-25 | The Regents Of The University Of California | Methods, systems, and compositions for delivery of nanobubbles in water treatment systems |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114956356A (en) * | 2022-06-09 | 2022-08-30 | 长江师范学院 | Mixed scale inhibitor and preparation method and application thereof |
| CN114956356B (en) * | 2022-06-09 | 2024-05-17 | 长江师范学院 | Mixed scale inhibitor and preparation method and application thereof |
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