Phosphorus-free corrosion and scale inhibitor as well as compounding method and application thereof

Abstract

The invention relates to the technical field of scale inhibitors, in particular to a non-phosphorus corrosion and scale inhibitor as well as a compounding method and application thereof, and the non-phosphorus corrosion and scale inhibitor comprises the following components in parts by mass: 10-1000 parts of glucarate or 1-500 parts of glucuronate, 1-300 parts of soluble alkali, 1-500 parts of organic acid and / or organic acid salt, 1-400 parts of corrosion inhibitor and 1-1000 parts of water. According to the phosphorus-free corrosion and scale inhibitor adopting the components and the compounding method and application thereof, the scale inhibition performance of glucarate or glucuronate is greatly improved, and through the efficient Ca < 2 + > resistance performance, the threshold effect and the good synergistic effect among agents after the glucarate / glucuronate is compounded with the organic acid and the corrosion inhibitor, the scale inhibition performance of the phosphorus-free corrosion and scale inhibitor is improved, and the scale inhibition effect of the phosphorus-free corrosion and scale inhibitor is improved. The formula effect of the phosphorus-free corrosion and scale inhibitor is improved, and the water treatment cost is greatly reduced.

Description

Technical Field

[0001] The invention relates to the technical field of scale inhibitors, and in particular to a phosphorus-free corrosion and scale inhibitor and a compounding method and application thereof. Background Art

[0002] The amount of circulating cooling water accounts for about 70% of the total industrial water consumption in my country, and with the development of social economy, the amount of circulating cooling water is increasing. The low-carbon treatment of circulating cooling water has become one of the difficult problems in industrial water treatment. The circulating cooling water system of power plants contains a large amount of cations such as calcium and magnesium and a variety of anions. As the water temperature rises, the anions and cations in the water will react with each other to form scale, which will not only greatly reduce the heat exchange efficiency, but also block the pipeline or cause under-scale corrosion. The current method for dealing with the scale problem is mainly to inhibit the formation of scale by adding scale inhibitors. Early scale inhibitors were mainly based on phosphorus-containing compounds such as phosphates, polyphosphates and polyacid salts. These compounds increase their solubility in sediments by forming soluble salts with calcium and magnesium ions. However, due to the negative impact of phosphorus on the environment (such as eutrophication of water bodies), these scale inhibitors are gradually restricted under the pressure of environmental protection regulations. The development of high-efficiency and low-consumption green scale inhibitors and corrosion inhibitors is the core of improving the efficiency of circulating cooling water treatment.

[0003] In recent years, green scale-inhibiting materials based on biosynthesis, such as Glucaric acid and Glucuronic acid, have made progress. Solugen and Kalion have successively completed the production of glucaric acid products, reducing its production cost and further promoting its application in the field of water treatment. Glucose has the properties of polyols and aldehydes. It is one of the pure natural biomass compounds, and a series of value-added chemicals can be obtained through oxidation. For example, glucaric acid is a potential green scale-inhibiting component, and it can work synergistically with a variety of scale inhibitors to exert efficient scale-inhibiting performance.

[0004] The invention patent (CN20221119177.29) discloses a low-phosphorus corrosion and scale inhibitor and a preparation method. First, dopamine hydrochloride, an organic acid and an alkaline aqueous solution are mixed, heated at 30-40°C and stirred for 1-3 hours to obtain a mixed solution; the prepared mixed solution is mixed with β-cyclodextrin and epichlorohydrin, and heated at the same temperature for 4 hours, and then neutralized with an acidic solution to obtain a neutralization reaction liquid, the neutralization reaction liquid is mixed with the scale inhibition component, dialyzed, separated, and then the mixed solution is reacted with epichlorohydrin. The low-phosphorus corrosion and scale inhibitor can promote the crystal distortion effect of the scale body crystal, and further inhibit the crystallization of CaCO3 and CaSO4 scale and the deposition of scale on the metal surface, thereby improving the scale inhibition efficiency of the corrosion and scale inhibitor. However, the invention has the disadvantages of high cost, large dosage and complex preparation process.

[0005] The invention patent (CN200910048317.1) discloses a compound antiscalant for treating circulating cooling water and its preparation method, which is composed of polyaspartic acid (PASP for short), HEDP (hydroxyethylene diphosphonic acid), ATMP (amino trimethylene phosphoric acid), SHMP (sodium hexametaphosphate), PESA (sodium polyepoxysuccinate), and polyol phosphate as basic components. The concentration of PASP is 10-25 mg / L, the concentration of HEDP is 1-5 mg / L, the concentration of ATMP is 1-5 mg / L, the concentration of PESA is 1-10 mg / L, the concentration of SHMP is 1-5 mg / L, and the concentration of polyol phosphate is 1-5 mg / L. The compound antiscalant reduces the secondary pollution of phosphorus-containing antiscalants to the environment, but the compound antiscalant is directly added to the circulating cooling water system, the concentration of the agent in the water body is unevenly distributed, and it is easy to waste or lack the agent, and some agents cannot continue to play a role, and the pH of the water body changes greatly.

[0006] The invention patent (CN201510368534.4) discloses a compound scale inhibitor for circulating cooling water, which is compounded by mass fraction with 10-30 parts of polyaspartic acid, 1-20 parts of hydroxyethylidene diphosphonic acid, 8-12 parts of polyepoxysuccinic acid, 1-5 parts of aminotrimethylene phosphonic acid, 100 parts of deionized water, 2-8 parts of sodium hexametaphosphate, 10-30 parts of dispersant, 6-14 parts of polyol phosphate, 40-60 parts of organic polyphosphonic acid, 20-40 parts of acrylic acid-acrylic acid phosphonic acid hydroxypropyl ester and 15-35 parts of organic solvent, with a corrosion inhibition rate of 0.001-0.01 mm / a; a scale inhibition rate of 98-100%; a long shelf life, and a scale inhibition effect of 99-100% when placed at 60-70°C for one month. The scale inhibition effect of the composite formula of the scale inhibitor is highly adaptable, but the phosphorus-containing water treatment agent is prone to eutrophication of the water body, causing secondary pollution to the environment.

[0007] In the above-mentioned research on compounding of low-phosphorus / non-phosphorus scale inhibitors, more attention is paid to compounding of existing low-phosphorus / non-phosphorus scale inhibitors, such as compounding of polyaspartic acid, polyepoxysuccinic acid, hydroxyethylidene diphosphate, sodium hexametaphosphate, etc., or studying new scale inhibitors through aqueous solutions of plant extracts. However, the scale inhibition effect of such scale inhibitors is poor and unstable. Therefore, studying new green scale inhibitors and compounding them with commercially available scale inhibitors can not only achieve better scale inhibition standards, but also meet the requirements of environmental protection development. Summary of the invention

[0008] The purpose of the present invention is to provide a phosphorus-free corrosion and scale inhibitor and a compounding method and application thereof. Based on the green and environmentally friendly scale inhibition characteristics of glucarate / glucuronate, it is compounded with organic acids such as polyacrylic acid and / or organic acid salts and corrosion inhibitors such as aluminum chloride and benzotriazole, so that the phosphorus-free corrosion and scale inhibitor can have a good scale inhibition effect on inorganic scale in a circulating cooling water system and organic scale in a reverse osmosis membrane system.

[0009] To achieve the above purpose, the present invention provides a phosphorus-free corrosion and scale inhibitor, wherein the components are, by mass, 10-1000 parts of glucarate or 1-500 parts of glucuronate, 1-500 parts of organic acid and / or organic acid salt, 1-300 parts of soluble alkali, 1-400 parts of corrosion inhibitor and 1-1000 parts of water.

[0010] Preferably, the organic acid includes one or more of polyacrylic acid, polyepoxysuccinic acid and ethylenediaminetetraacetic acid.

[0011] Preferably, the corrosion inhibitor comprises one or more of benzotriazole, sulfonated lignin, molybdate, zinc chloride and aluminum chloride.

[0012] Preferably, the soluble base includes one or more of sodium hydroxide, potassium hydroxide, lithium hydroxide, sodium carbonate and sodium bicarbonate.

[0013] The compounding method of the above-mentioned phosphorus-free corrosion and scale inhibitor comprises the following steps: S1. Preparation of solution: weigh 10-1000 parts of glucarate or 1-500 parts of glucuronate, 1-500 parts of organic acid and / or organic acid salt, 1-400 parts of corrosion inhibitor, 1-300 parts of soluble alkali and 1-1000 parts of water according to mass parts; S2, preparation of a solution: mixing glucarate or glucuronate with an organic acid and / or an organic acid salt, adding pure water, and reacting under stirring to obtain a first solution; S3. Solution preparation: adding corrosion inhibitor and soluble alkali to the first solution in S2, stirring to obtain phosphorus-free corrosion and scale inhibitor.

[0014] Preferably, the molar ratio of glucarate or glucuronate to the corrosion inhibitor is 1:1-5.

[0015] Preferably, in S2, the stirring speed is 300 r / min, and the reaction is stirred at 20-40 °C for 30 min.

[0016] Preferably, in S3, the stirring speed is maintained at 300 r / min, and the reaction is stirred in a 10-100 °C water bath for 0-2 h.

[0017] The above-mentioned phosphorus-free corrosion and scale inhibitor is used in a reverse osmosis membrane system or a circulating cooling water system.

[0018] The mechanism of the present invention is: Glucaric acid increases the solubility of hard acid ions in solution through chelation solubilization and lattice distortion, with Ca 2+ For example, glucaric acid is first deprotonated, and the resulting carboxylate anion groups react with Ca in water. 2+ Binding increases Ca 2+ Secondly, glucaric acid can be adsorbed on the crystal surface, preferentially occupying the growth site on the surface of calcite-type calcium carbonate, destroying the calcium carbonate crystal structure and causing the crystal structure to change, that is, lattice distortion occurs, which is dispersed and discharged with the continuous impact of water flow, inhibiting the deposition of calcium carbonate scale.

[0019] The present invention uses organic acid and / or organic acid salt to compound with glucarate or glucuronate to improve the scale inhibition effect. Glucarate or glucuronate contains multiple hydroxyl (-OH) and carboxyl (-COOH) functional groups; there are multiple carboxyl (-COOH) functional groups in the molecular structure of organic acid and / or organic acid salt. After the two are compounded in a certain proportion, the synergistic effect of multiple functional groups can increase the chance and stability of binding with metal ions. At the same time, their molecular arrangement and interaction mode make it easier for metal ions to be surrounded and combined, further improving the efficiency and strength of chelation and improving the scale inhibition effect.

[0020] The nitrogen atoms containing lone pairs of electrons in benzotriazole coordinate and adsorb with the empty orbitals of Fe and Cu atoms on the metal surface to form a stable complex, forming a protective layer on the metal surface, slowing down the corrosion rate of the metal material. Aluminum chloride and sodium hydroxide react to form aluminum hydroxide; aluminum hydroxide forms a dense protective film on the metal surface, which slows down the corrosion rate through adsorption, complexation, passivation and other effects. When the two are used together, the nitrogen atoms of benzotriazole can interact with the aluminum ions in sodium aluminate, further stabilizing the protective film and enhancing the corrosion inhibition effect.

[0021] Therefore, the present invention adopts the above technical solution, and its beneficial effects are: 1. The present invention uses glucarate or glucuronate, which is difficult to be metabolized by organisms. When used in a reverse osmosis membrane system, it is difficult for microorganisms to utilize and produce extracellular secretions, thereby reducing biological contamination, thereby extending the service life of the reverse osmosis membrane and reducing the replacement frequency; 2. Glucarate or glucuronate can not only effectively combine with calcium and magnesium ions to form a variety of complexes, which have high solubility in water, thus effectively preventing the formation of scale, but also have good biodegradability and environmental friendliness; 3. The present invention uses organic acid and / or organic acid salt to compound with glucarate to greatly improve the scale inhibition performance of glucarate or glucuronate, improves the formulation effect of phosphorus-free corrosion and scale inhibitor through good synergistic effect between agents, and greatly reduces water treatment costs; 4. The components of the phosphorus-free corrosion and scale inhibitor provided by the present invention improve the scale inhibition effect of the scale inhibitor through synergistic effect, and have the advantages of wide applicable water quality range, convenient use and operation, small dosage, strong scale inhibition, good corrosion inhibition effect, and large amount of water resource saving; 5. The phosphorus-free corrosion and scale inhibitor provided by the present invention has high Ca 2+ Concentration calcium scale resistance, for calcium sulfate Ca 2+ The concentration range is 0-1500 mg / L for calcium carbonate Ca 2+ The concentration range is 0-600 mg / L; 6. Effect of the phosphorus-free corrosion and scale inhibitor provided by the present invention on humic acid-Ca 2+ , polysaccharide-Ca 2+ , protein-Ca 2+ It also has good scale inhibition performance against organic scale.

[0022] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 is a schematic flow chart of the compounding method in Example 1 of the present invention; Figure 2 It is a schematic diagram of the dynamic scale inhibition performance testing device in Test Example 1 of the present invention. DETAILED DESCRIPTION

[0024] The present invention is further described below in conjunction with the accompanying drawings and embodiments. Unless otherwise defined, the technical terms or scientific terms used in the present invention should be the common meanings understood by people with ordinary skills in the field to which the present invention belongs. The above-mentioned features or features mentioned in the specific examples mentioned in the present invention can be combined arbitrarily, and these specific embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention.

[0025] Example 1 like Figure 1 As shown, the compounding method of the phosphorus-free corrosion and scale inhibitor comprises the following steps: S1. Weigh 60 parts of potassium glucarate, 16 parts of aluminum chloride, 16 parts of sodium hydroxide, 10 parts of polyacrylic acid, 50 parts of benzotriazole and 500 parts of pure water according to their mass ratios; S2, mixing potassium glucarate and polyacrylic acid, adding pure water, stirring at 30°C for 30 min at a stirring speed of 300 r / min, and reacting under stirring to obtain a first solution; S3. Add aluminum chloride, sodium hydroxide and benzotriazole to the first solution in S2, keep the stirring speed at 300 r / min, and stir at 60 °C for 1 h to obtain a phosphorus-free corrosion and scale inhibitor.

[0026] Example 2 S1. Weigh 60 parts of potassium glucarate, 24 parts of aluminum chloride, 24 parts of sodium hydroxide, 10 parts of polyacrylic acid, 50 parts of benzotriazole and 500 parts of pure water according to their mass ratios; S2, mixing potassium glucarate and polyacrylic acid, adding pure water, stirring at 30°C for 30 min at a stirring speed of 300 r / min, and reacting under stirring to obtain a first solution; S3. Add aluminum chloride, sodium hydroxide and benzotriazole to the first solution in S2, keep the stirring speed at 300 r / min, and stir at 60 °C for 1 h to obtain a phosphorus-free corrosion and scale inhibitor.

[0027] Example 3 S1. Weigh 60 parts of potassium glucarate, 32 parts of aluminum chloride, 32 parts of sodium hydroxide, 10 parts of polyacrylic acid, 50 parts of benzotriazole and 500 parts of pure water according to their mass ratios; S2, mixing potassium glucarate and polyacrylic acid, adding pure water, stirring at 30°C for 30 min at a stirring speed of 300 r / min, and reacting under stirring to obtain a first solution; S3. Add aluminum chloride, sodium hydroxide and benzotriazole to the first solution in S2, keep the stirring speed at 300 r / min, and stir at 60 °C for 1 h to obtain a phosphorus-free corrosion and scale inhibitor.

[0028] Example 4 S1. Weigh 60 parts of potassium glucarate, 40 parts of aluminum chloride, 40 parts of sodium hydroxide, 10 parts of polyacrylic acid, 50 parts of benzotriazole and 500 parts of pure water according to their mass ratios; S2, mixing potassium glucarate and polyacrylic acid, adding pure water, stirring at 30°C for 30 min at a stirring speed of 300 r / min, and reacting under stirring to obtain a first solution; S3. Add aluminum chloride, sodium hydroxide and benzotriazole to the first solution in S2, keep the stirring speed at 300 r / min, and stir at 60 °C for 1 h to obtain a phosphorus-free corrosion and scale inhibitor.

[0029] Example 5 S1. Weigh 30 parts of potassium glucarate, 8 parts of aluminum chloride, 8 parts of sodium hydroxide, 5 parts of polyacrylic acid, 25 parts of benzotriazole and 500 parts of pure water according to their mass ratios; S2, mixing potassium glucarate and polyacrylic acid, adding pure water, stirring at 30°C for 30 min at a stirring speed of 300 r / min, and reacting under stirring to obtain a first solution; S3. Add aluminum chloride, sodium hydroxide and benzotriazole to the first solution in S2, keep the stirring speed at 300 r / min, and stir at 60 °C for 1 h to obtain a phosphorus-free corrosion and scale inhibitor.

[0030] Example 6 S1. Weigh 30 parts of potassium glucarate, 12 parts of aluminum chloride, 12 parts of sodium hydroxide, 5 parts of polyacrylic acid, 25 parts of benzotriazole and 500 parts of pure water according to their mass ratios; S2, mixing potassium glucarate and polyacrylic acid, adding pure water, stirring at 30°C for 30 min at a stirring speed of 300 r / min, and reacting under stirring to obtain a first solution; S3. Add aluminum chloride, sodium hydroxide and benzotriazole to the first solution in S2, keep the stirring speed at 300 r / min, and stir at 60 °C for 1 h to obtain a phosphorus-free corrosion and scale inhibitor.

[0031] Example 7 S1. Weigh 30 parts of potassium glucarate, 18 parts of aluminum chloride, 18 parts of sodium hydroxide, 5 parts of polyacrylic acid, 25 parts of benzotriazole and 500 parts of pure water according to their mass ratios; S2, mixing potassium glucarate and polyacrylic acid, adding pure water, stirring at 30°C for 30 min at a stirring speed of 300 r / min, and reacting under stirring to obtain a first solution; S3. Add aluminum chloride, sodium hydroxide and benzotriazole to the first solution in S2, keep the stirring speed at 300 r / min, and stir at 60 °C for 1 h to obtain a phosphorus-free corrosion and scale inhibitor.

[0032] Example 8 S1. Weigh 30 parts of potassium glucarate, 20 parts of aluminum chloride, 20 parts of sodium hydroxide, 5 parts of polyacrylic acid, 25 parts of benzotriazole and 500 parts of pure water according to their mass ratios; S2, mixing potassium glucarate and polyacrylic acid, adding pure water, stirring at 30°C for 30 min at a stirring speed of 300 r / min, and reacting under stirring to obtain a first solution; S3. Add aluminum chloride, sodium hydroxide and benzotriazole to the first solution in S2, keep the stirring speed at 300 r / min, and stir at 60 °C for 1 h to obtain a phosphorus-free corrosion and scale inhibitor.

[0033] Example 9 S1. Weigh 40 parts of potassium glucarate, 18 parts of aluminum chloride, 18 parts of sodium hydroxide, 20 parts of polyacrylic acid, 10 parts of benzotriazole and 100 parts of pure water according to their mass ratios; S2, mixing potassium glucarate and polyacrylic acid, adding pure water, stirring at 30°C for 30 min at a stirring speed of 300 r / min, and reacting under stirring to obtain a first solution; S3. Add aluminum chloride, sodium hydroxide and benzotriazole to the first solution in S2, keep the stirring speed at 300 r / min, and stir at 60 °C for 1 h to obtain a phosphorus-free corrosion and scale inhibitor.

[0034] Example 10 S1. Weigh 215 parts of potassium glucarate, 97 parts of aluminum chloride, 97 parts of sodium hydroxide, 70 parts of polyacrylic acid, 40 parts of benzotriazole and 900 parts of pure water according to their mass ratios; S2, mixing potassium glucarate and polyacrylic acid, adding pure water, stirring at 30°C for 30 min at a stirring speed of 300 r / min, and reacting under stirring to obtain a first solution; S3. Add aluminum chloride, sodium hydroxide and benzotriazole to the first solution in S2, keep the stirring speed at 300 r / min, and stir at 60 °C for 1 h to obtain a phosphorus-free corrosion and scale inhibitor.

[0035] Embodiment 11 S1. Weigh 430 parts of potassium glucarate, 150 parts of polyacrylic acid, 193 parts of aluminum chloride, 193 parts of sodium hydroxide, 70 parts of benzotriazole and 900 parts of pure water according to their mass ratios; S2, mixing potassium glucarate and polyacrylic acid, adding pure water, stirring at 30°C for 30 min at a stirring speed of 300 r / min, and reacting under stirring to obtain a first solution; S3. Add aluminum chloride, sodium hydroxide and benzotriazole polyacrylic acid to the first solution in S2, keep the stirring speed at 300 r / min, and stir at 60 °C for 1 h to obtain a phosphorus-free corrosion and scale inhibitor.

[0036] Example 12 S1. Weigh 642 parts of potassium glucarate, 256 parts of polyacrylic acid, 288 parts of aluminum chloride, 288 parts of sodium hydroxide, 100 parts of benzotriazole and 900 parts of pure water according to their mass fractions; S2, mixing potassium glucarate and polyacrylic acid, adding pure water, stirring at 30°C for 30 min at a stirring speed of 300 r / min, and reacting under stirring to obtain a first solution; S3. Add aluminum chloride, sodium hydroxide and benzotriazole polyacrylic acid to the first solution in S2, keep the stirring speed at 300 r / min, and stir at 60 °C for 1 h to obtain a phosphorus-free corrosion and scale inhibitor.

[0037] Test Example 1 a. Scale inhibition performance test The scale inhibition test method mainly refers to GB / T16632-2019 "Determination of scale inhibition performance of water treatment agents-calcium carbonate precipitation method" and Q / SY126-2014 "Technical Specifications for Corrosion and Scale Inhibitors for Oilfield Water Treatment".

[0038] a1. Prepare water with different concentrations of calcium carbonate and calcium sulfate, take three equal parts of the phosphorus-free corrosion and scale inhibitor in Examples 1-8, and calculate the average scale inhibition rate as shown in Table 1.

[0039] Table 1. Scale inhibition rate of phosphorus-free corrosion and scale inhibitors in Examples 1-8 under different water quality configurations

[0040] a2. Take the non-phosphorus corrosion and scale inhibitor obtained in Example 9, prepare solutions with concentrations of 0.5 mg / L, 2.5 mg / L, 5 mg / L, and 10 mg / L, add water samples from the Dabie Mountain Power Plant in Hubei Province, and heat at 80°C for 1 h to measure the scale inhibition performance. The scale inhibition performance of actual water samples was tested, with three samples in each group. At a composite scale inhibitor concentration of 10 mg / L, the average scale inhibition rate of the three samples was 95%.

[0041] b. Dynamic scale inhibition performance test like Figure 2 As shown, dynamic anti-scaling detection is carried out in the following order: b1. Clean water compaction: Pour deionized water into the raw water tank and conduct a continuous compaction experiment for 6 hours at a pressure of 10 bar until the filtrate flow rate reaches a stable value.

[0042] b2. Electrolyte stability: The inlet pH is 7, and the NaCl solution with an ionic strength of 10 mM is operated at an operating pressure of 9 bar for 6 hours to stabilize the membrane flux.

[0043] b3. Mixed pollution experiment: Keep the operating pressure at 9 bar, adjust the pH of the water to 7 with HCl or NaOH, change the composition of the original water tank solution according to the experimental group, and set up a blank control group. The pollution experiment runs continuously for 10 hours. During the operation of the pollution experiment, record the change of the reverse osmosis membrane water production over time.

[0044] b4. Chemical cleaning experiment: Under an operating pressure of 9 bar, 2 wt% sodium citrate in the raw water tank was added with ammonia water to adjust the pH to 4; 5 mM EDTA was added and the pH was adjusted to 11 with NaOH. The cleaning time was 30 min.

[0045] b5. Membrane flux recovery experiment: Clean the membrane and raw water tank with deionized water to remove the residual cleaning solution until the pH value of the water in the raw water tank is consistent with that of the inlet water. Finally, operate the cleaned membrane with deionized water for 6 hours at a pressure of 10 bar to test the flux of the cleaned membrane.

[0046] The phosphorus-free corrosion and scale inhibitors of Examples 10-12 were tested three times to obtain an average membrane fouling specific flux rate, as shown in Table 2.

[0047] Table 2. Average membrane fouling flux rate of Examples 10-12 under different water qualities

[0048] The phosphorus-free corrosion and scale inhibitors of Examples 2, 6, and 9 were tested three times to obtain an average membrane fouling specific flux rate, as shown in Table 3.

[0049] Table 3. Average membrane fouling flux rate of Examples 2, 6, and 9 under different water qualities

[0050] It can be seen from the data obtained in Test Example 1 that the phosphorus-free corrosion and scale inhibitor provided by the present invention has a good scale inhibition effect in a high hardness and high alkalinity environment. Adding polyacrylic acid, reducing the amount of potassium glucarate, and controlling the molar ratio of polyacrylic acid to the corrosion inhibitor to 1:1-5 can significantly improve the scale inhibition rate and meet environmental protection requirements when used.

[0051] Therefore, the present invention adopts a phosphorus-free corrosion and scale inhibitor of the above-mentioned components and its compounding method and application, and based on the green and environmentally friendly scale inhibition characteristics of glucarate / glucuronate, it is compounded with organic acids such as polyacrylic acid and / or organic acid salts, benzotriazole and other corrosion inhibitors, so that the phosphorus-free corrosion and scale inhibitor can have a good scale inhibition effect on inorganic scale in the circulating cooling water system and organic scale in the reverse osmosis membrane system.

[0052] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solution of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of the present invention.

Claims

1. A phosphorus-free corrosion and scale inhibitor, characterized in that: The components are calculated by weight as follows: 10-1000 parts of glucarate or 1-500 parts of glucuronate, 1-300 parts of soluble alkali, 1-500 parts of organic acid and / or organic acid salt, 1-400 parts of corrosion inhibitor and 1-1000 parts of water.

2. The phosphorus-free corrosion and scale inhibitor according to claim 1, characterized in that: The organic acid includes one or more of polyacrylic acid, polyepoxysuccinic acid, and ethylenediaminetetraacetic acid.

3. The phosphorus-free corrosion and scale inhibitor according to claim 1, characterized in that: The corrosion inhibitor includes one or more of benzotriazole, sulfonated lignin, molybdate, zinc chloride and aluminum chloride.

4. A method for compounding the phosphorus-free corrosion and scale inhibitor according to any one of claims 1 to 3, characterized in that: The following steps are included: S1. Weigh 10-1000 parts of glucarate or 1-500 parts of glucuronate, 1-300 parts of soluble base, 1-500 parts of organic acid and / or organic acid salt, 1-400 parts of corrosion inhibitor and 1-1000 parts of water according to mass proportions; S2, mixing glucarate or glucuronate with an organic acid and / or an organic acid salt, adding water, and reacting under stirring to obtain a first solution; S3. Add corrosion inhibitor and soluble alkali to the first solution in S2, and stir to obtain phosphorus-free corrosion and scale inhibitor.

5. The compounding method of a phosphorus-free corrosion and scale inhibitor according to claim 4, characterized in that: The molar ratio of glucarate or glucuronate to the corrosion inhibitor is 1:1-5.

6. The compounding method of a phosphorus-free corrosion and scale inhibitor according to claim 4, characterized in that: In S2, the stirring speed is 300 r / min, and the reaction is stirred at 20-40°C for 30 min.

7. The compounding method of a phosphorus-free corrosion and scale inhibitor according to claim 4, characterized in that: In S3, the stirring speed was maintained at 300 r / min, and the reaction was stirred in a 10-100 °C water bath for 0-2 h.

8. An application of the phosphorus-free corrosion and scale inhibitor according to any one of claims 1 to 3, characterized in that: Phosphorus-free corrosion and scale inhibitors are used in reverse osmosis membrane systems or circulating cooling water systems.

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