Corrosion and scale inhibitor, its preparation method and application

Abstract

The present application relates to the technical field of environmental protection material, and discloses a kind of corrosion inhibitor and its preparation method and application.A kind of corrosion inhibitor includes by the component of following mass fraction is prepared: polyaspartic acid derivative 140~160 parts, quaternary ammonium salt 95~105 parts, sodium molybdate 25~35 parts, thiourea 45~55 parts, potassium iodide 3~7 parts, solvent 600~700 parts.The corrosion inhibitor provided in the present application is polyaspartic acid derivative and quaternary ammonium salt as main component, and sodium molybdate is used as synergistic adjuvant, which is a new type of corrosion inhibitor with non-phosphorus, environmental friendly, excellent performance.The preparation method of the corrosion inhibitor is simple, acetone can be recycled and reused, meets the environmental protection requirements, and is suitable for industrial production.When applied to oilfield water system, the corrosion rate is slow, the scale inhibition rate of calcium carbonate, calcium sulfate and barium sulfate can reach more than 90%, and the compatibility with other agents is good, which is suitable for practical use.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of environmental protection materials, in particular to an inhibitor and scale inhibitor, a preparation method and application thereof. BACKGROUND

[0002] In the oilfield water system, the scaling phenomenon will occur in the whole water flow path from the water injection equipment to the oil reservoir and then to the ground equipment. Once scaling occurs, it will not only affect the heat transfer effect of the equipment, cause blockage, increase the water flow resistance and transportation energy, but also seriously affect the effective film formation of the corrosion inhibitor, so that the corrosion inhibitor loses the expected corrosion inhibition performance and increases the risk of under-deposit corrosion and bacterial corrosion. The scaling types in the oilfield water system are relatively complex, and are generally calcium carbonate scale, calcium sulfate scale and barium sulfate scale.

[0003] The inhibitor and scale inhibitor is a composite agent with dual functions of corrosion inhibition and scale inhibition, which is developed according to the characteristics of specific water quality and production requirements. It is used to prevent the deposition of water scale such as calcium carbonate, calcium sulfate and calcium phosphate in the circulating water pipeline, and reduce the corrosion of metal materials in the circulating water. After decades of development, the inhibitor and scale inhibitor has not only been rapidly improved in corrosion inhibition and scale inhibition effect, but also greatly reduced in dosage, and continuously enhanced in use function. In terms of use function, it has developed from sodium polyacrylate with only calcium carbonate inhibition effect to acrylate-acrylic acid binary copolymer, acrylate-acrylic acid ternary copolymer, acrylate-maleic acid-acrylic acid quaternary copolymer and the like with excellent calcium carbonate inhibition, calcium phosphate inhibition and sulfate inhibition, and then to HEDP, HPAA and the like with both scale inhibition effect and good corrosion inhibition effect.

[0004] With the increasing environmental protection requirements, chromium-based corrosion inhibitors are banned, and phosphorus-based formulations are limited due to the fact that phosphorus compounds are easy to nourish bacteria and algae and cause eutrophication of water bodies. Therefore, it is urgent to develop a new type of inhibitor and scale inhibitor with low or no phosphorus, environmental friendliness and excellent performance. SUMMARY

[0005] The present application aims at at least solving one of the above-mentioned technical problems in the prior art. To this end, one of the objects of the present application is to provide an inhibitor and scale inhibitor, the second object of the present application is to provide a preparation method of the inhibitor and scale inhibitor, and the third object of the present application is to provide the application of the inhibitor and scale inhibitor.

[0006] In order to achieve the above-mentioned objects, the technical scheme adopted by the present application is as follows:

[0007] The first aspect of the present application provides a corrosion and scale inhibitor, comprising components prepared by the following mass fractions: polyaspartic acid derivative 140 ~ 160 parts, quaternary ammonium salt 95 ~ 105 parts, sodium molybdate 25 ~ 35 parts, thiourea 45 ~ 55 parts, potassium iodide 3 ~ 7 parts, solvent 600 ~ 700 parts.

[0008] The basic principle of the present application is explained as follows:

[0009] (1) Polyaspartic acid has high scale inhibition activity, good biodegradability, non-toxicity, and no effect on the corrosion of high-concentration Ca 2+ It has good scale inhibition effect, is a new green scale inhibitor, the imidazoline corrosion inhibitor is an environmentally friendly corrosion inhibitor, the preparation method is simple, non-toxic, and only a small amount is needed to have good corrosion inhibition effect, and the performance is excellent. The polyaspartic acid derivative provided by the present application uses poly succinimide as a base, and is modified by using N-(3-aminopropyl) imidazole, 2-amino-1, 3-propanediol and mercaptoethylamine three different functional groups. The modified polyaspartic acid derivative has the effects of corrosion inhibition and scale inhibition, and is one of the main components of the corrosion and scale inhibitor. Among them, in the N-(3-aminopropyl) imidazole, the nitrogen atom is a heteroatom with high electronegativity, and contains an unshared lone pair of electrons, which can interact with the empty d orbital of the metal atom (such as iron) in the conveying pipeline to form a coordination bond, so that the corrosion inhibitor molecule is adsorbed on the metal; the double bond and the aromatic ring group contain π electron structure, and the organic corrosion inhibitor containing such group can also react with the empty d orbital of the metal atom to form a coordination bond; when the center atom group with strong polarity and the π electron structure are adjacent, the lone pair of electrons of the center atom can also form a conjugated π bond (large π bond) with the π electron, so as to be adsorbed on the metal surface in a planar structure, which can greatly improve the corrosion inhibition effect; the amino group (-NH2) plays a role in opening the ring chain of poly succinimide, and the N-(3-aminopropyl) imidazole has low biological toxicity, which meets the principle of green environmental protection. The role of 2-amino-1, 3-propanediol is mainly scale inhibition and corrosion inhibition, and the reason for selecting the hydroxyl group (-OH) is that the selection of acidic scale inhibitor will accelerate the corrosion of equipment, and the selection of alkaline scale inhibitor can have the effect of corrosion inhibition, and -OH has good corrosion inhibition effect on Ca 2+ , Mg 2+The growth of the scale crystal is inhibited, and the scale inhibition mechanism belongs to the combination of chelation and dispersion. In the screening process, 2-amino-2-methyl-1-propanol containing the same hydroxyl group and 2-amino-1, 3-propanediol with higher hydroxyl content are compared, and the 2-amino-1, 3-propanediol has better scale inhibition and corrosion resistance performance. The effect of the amino group (-NH2) is to open the ring of the poly succinimide. The effect of 3-mercaptoethylamine is similar to that of N-(3-aminopropyl) imidazole. The sulfur atom is a heteroatom with high electronegativity, and contains an unshared pair of electrons, which can interact with the empty d orbitals of the metal atoms (such as iron) in the conveying pipeline to form a coordination bond, so that the corrosion inhibitor molecules are adsorbed on the metal. The main consideration factor is the steric hindrance of the modified group. If the molecular structure of the modified group is large, the molecular weight of the polymer product will be affected, and the size of the molecular weight will further affect the performance, especially the difficulty of being extracted under the supercritical CO2 condition, so the proportion of mercaptoethylamine is the largest. The effect of the amino group is to open the ring of the poly succinimide.

[0010] (2) The corrosion and scale inhibitor provided by the application takes quaternary ammonium salt as another main component, the quaternary ammonium salt has the characteristics of olefins, amines and ester compounds, and contains groups such as heteroatoms (N, O) and double bonds which can be effectively adsorbed on the metal surface. In the acidic medium, the introduction of a benzene ring with strong hydrophobicity in the structure of the corrosion inhibitor can effectively improve the corrosion inhibition performance and greatly reduce the desorption at high temperatures.

[0011] (3) The corrosion and scale inhibitor provided by the application takes molybdate, thiourea and potassium iodide as synergistic agents. The molybdate is an anodic corrosion inhibitor, which can form a complex film of ferrous-ferric-molybdenum oxide on the iron anode to prevent further corrosion of iron, and also has certain scale inhibition performance. It has strong complexing ability for calcium, magnesium and iron salts, especially for Fe 3+ It has excellent chelation; thiourea is mainly used in acidic environments. The sulfur atom has an empty orbital, which can reduce the electron cloud density of Fe by adsorbing on the surface of Fe to play a corrosion inhibition role. Potassium iodide is a commonly used corrosion inhibitor, which can slow down the corrosion rate of metal. When in contact with the metal surface, the iodine ions in the potassium iodide will react with the iron ions on the metal surface to form a dense iron iodide protective film.

[0012] Preferably, the polyaspartic acid derivative comprises components prepared by the following mass fractions: poly succinimide 250 ~ 280 parts, N-(3-aminopropyl) imidazole 45 ~ 55 parts, mercaptoethylamine 85 ~ 100 parts, 2-amino-1, 3-propanediol 30 ~ 40 parts, lye 55 ~ 65 parts, and water 15 ~ 30 parts.

[0013] Preferably, the quaternary ammonium salt comprises components prepared by the following mass fractions: dimethylaminoethyl methacrylate 150 ~ 170 parts, p-chloromethylstyrene 160 ~ 180 parts, acetone 70 ~ 90 parts.

[0014] Preferably, the solvent comprises an organic solvent and water.

[0015] Preferably, the ratio of the organic solvent to water is 1: (3 ~ 5); further preferably, the ratio of the organic solvent to water is 1: (3.5 ~ 4.5).

[0016] Preferably, the organic solvent comprises at least one of methanol, ethanol, acetone, ethyl acetate, dimethyl sulfoxide, diethyl ether, acetonitrile.

[0017] Preferably, in the component of the polyaspartic acid derivative, the alkali source of the lye is an alkali metal hydroxide; further preferably, in the component of the polyaspartic acid derivative, the alkali source of the lye comprises at least one of NaOH, KOH.

[0018] Preferably, in the component of the polyaspartic acid derivative, the mass fraction of the lye is 15 ~ 25 wt%; further preferably, in the component of the polyaspartic acid derivative, the mass fraction of the lye is 18 ~ 22 wt%.

[0019] The second aspect of the present application provides a preparation method of the corrosion and scale inhibitor according to the first aspect of the present application, comprising the following steps:

[0020] (1) respectively preparing a polyaspartic acid derivative and a quaternary ammonium salt;

[0021] (2) mixing potassium iodide, sodium molybdate, thiourea, an organic solvent, a polyaspartic acid derivative, a quaternary ammonium salt and water according to the composition of the corrosion and scale inhibitor according to the first aspect of the present application to obtain the corrosion and scale inhibitor.

[0022] Preferably, in the step (1), the preparation of the polyaspartic acid derivative comprises the following steps:

[0023] A1. Mix N-(3-aminopropyl)imidazole with water, stir, and heat;

[0024] A2. Add poly succinimide, mix, and react;

[0025] A3. Add 2-amino-1,3-propanediol, mercaptoethylamine and water, mix, and react;

[0026] A4. Add lye, mix, and react to obtain a polyaspartic acid derivative.

[0027] Preferably, in the step (1), the preparation of polyaspartic acid derivative, the water added in step A1 is 50 ~ 55% of the total amount of water; further preferably, in the step (1), the preparation of polyaspartic acid derivative, the water added in step A1 is 51 ~ 54% of the total amount of water.

[0028] Preferably, in the step (1), the preparation of polyaspartic acid derivative, the stirring time of step A1 is 5 ~ 15min; further preferably, in the step (1), the preparation of polyaspartic acid derivative, the stirring time of step A1 is 8 ~ 12min.

[0029] Preferably, in the step (1), the preparation of polyaspartic acid derivative, the heating temperature of step A1 is 55 ~ 65℃; further preferably, in the step (1), the preparation of polyaspartic acid derivative, the heating temperature of step A1 is 58 ~ 62℃.

[0030] Preferably, in the step (1), the preparation of polyaspartic acid derivative, the reaction time of step A2 is 4 ~ 8h; further preferably, in the step (1), the preparation of polyaspartic acid derivative, the reaction time of step A2 is 5 ~ 7h.

[0031] Preferably, in the step (1), the preparation of polyaspartic acid derivative, the reaction time of step A3 is 10 ~ 14h; further preferably, in the step (1), the preparation of polyaspartic acid derivative, the reaction time of step A3 is 11 ~ 13h.

[0032] Preferably, in the step (1), the preparation of polyaspartic acid derivative, the reaction time of step A4 is 4 ~ 8h; further preferably, in the step (1), the preparation of polyaspartic acid derivative, the reaction time of step A4 is 5 ~ 7h.

[0033] Preferably, in the step (1), the preparation of polyaspartic acid derivative, the adding mode of alkali solution in step A4 is dropwise.

[0034] Preferably, in the step (1), the preparation of polyaspartic acid derivative, the dropwise adding time of alkali solution in step A4 is <60min.

[0035] Preferably, in the step (1), the preparation of polyaspartic acid derivative, the pH value of the system is 6 ~ 9; further preferably, in the step (1), the preparation of polyaspartic acid derivative, the pH value of the system is 7 ~ 8.

[0036] Preferably, in the step (1), the appearance of polyaspartic acid derivative is light yellow liquid.

[0037] Preferably, in the step (1), the solid content of the polyaspartic acid derivative is 75 ~ 85%; further preferably, in the step (1), the solid content of the polyaspartic acid derivative is 79 ~ 81%.

[0038] Preferably, in the step (1), the preparation of the quaternary ammonium salt comprises the following steps:

[0039] B1. Mix dimethylaminoethyl methacrylate, p-chloromethylstyrene and acetone, heat to 45 ~ 55℃ and then keep constant temperature for reaction;

[0040] B2. Vacuum fractionation, separate and recover acetone to obtain the quaternary ammonium salt.

[0041] Preferably, in the step (1), the preparation of the quaternary ammonium salt, the constant temperature reaction time of step B1 is 4 ~ 8 h; further preferably, in the step (1), the preparation of the quaternary ammonium salt, the constant temperature reaction time of step B1 is 5 ~ 7 h.

[0042] Preferably, in the step (1), the preparation of the quaternary ammonium salt, the vacuum fractionation time of step B2 is 20 ~ 40 min; preferably, in the step (1), the preparation of the quaternary ammonium salt, the vacuum fractionation time of step B2 is 25 ~ 35 min.

[0043] Preferably, in the step (1), the preparation of the quaternary ammonium salt, the recovery rate of acetone in step B2 is > 97%.

[0044] Preferably, in the step (1), the appearance of the quaternary ammonium salt is orange to brown liquid.

[0045] Preferably, in the step (1), the solid content of the quaternary ammonium salt is > 98%.

[0046] Preferably, in the step (2), when the potassium iodide, sodium molybdate, thiourea, organic solvent, polyaspartic acid derivative and quaternary ammonium salt are mixed with water, stirring operation is assisted.

[0047] Preferably, in the step (2), when the potassium iodide, sodium molybdate, thiourea, organic solvent, polyaspartic acid derivative and quaternary ammonium salt are mixed with water, each component needs to react for 20 ~ 40 min after being added; further preferably, in the step (2), when the potassium iodide, sodium molybdate, thiourea, organic solvent, polyaspartic acid derivative and quaternary ammonium salt are mixed with water, each component needs to react for 25 ~ 35 min after being added.

[0048] Preferably, the appearance of the corrosion and scale inhibitor obtained in the step (2) is orange to brown liquid.

[0049] Preferably, the solid content of the corrosion and scale inhibitor obtained in step (2) is 30-40%; further preferably, the solid content of the corrosion and scale inhibitor obtained in step (2) is 33-35%.

[0050] The third aspect of the present application provides application of the corrosion and scale inhibitor of the first aspect of the present application in an oilfield water system.

[0051] Compared with the prior art, the present application has the following beneficial effects:

[0052] 1) The corrosion and scale inhibitor provided by the present application is a new type of corrosion and scale inhibitor which is phosphorus-free, environmentally friendly and has excellent performance, and is mainly composed of polyaspartic acid derivatives and quaternary ammonium salt, and is compounded with sodium molybdate, thiourea and other synergistic additives.

[0053] 2) The preparation method of the corrosion and scale inhibitor provided by the present application is simple, the acetone produced by distillation can be recycled and reused, meets the environmental protection requirements, and is suitable for industrial production.

[0054] 3) When the corrosion and scale inhibitor provided by the present application is applied in an oilfield water system, the corrosion rate is slow, the scale inhibition rate of calcium carbonate, calcium sulfate and barium sulfate can reach more than 90%, the corrosion and scale inhibition effect is good, the compatibility with other agents is good, and the effect of the agents such as demulsifier and water clarifier is not affected, and the corrosion and scale inhibitor is suitable for practical use. BRIEF DESCRIPTION OF DRAWINGS

[0055] Figure 1 Synthesis principle diagram of polyaspartic acid derivatives;

[0056] Figure 2 Product characterization result diagram of polyaspartic acid derivatives;

[0057] Figure 3 Synthesis principle diagram of quaternary ammonium salt;

[0058] Figure 4 Product characterization result diagram of quaternary ammonium salt;

[0059] Figure 5 Comparison diagram of compatibility test of the corrosion and scale inhibitor and demulsifier HYP-121;

[0060] Figure 6 Comparison diagram of compatibility test of the corrosion and scale inhibitor and water clarifier HYQ-131;

[0061] Figure 7 Comparison diagram of compatibility test of the corrosion and scale inhibitor and demulsifier HYP-121 and water clarifier HYQ-131. DETAILED DESCRIPTION

[0062] The application will be further described in detail by specific examples. The raw materials, reagents or devices used in the examples are commercially available or can be obtained by prior art methods unless otherwise specified. The test or test method is the conventional method in the art unless otherwise specified.

[0063] The experimental site is Wushi oilfield group. The Wushi oilfield group currently includes Wushi 17-2 oilfield group and Wushi 23-5 oilfield group, with a cumulative proven reserve of nearly 100 million cubic meters. Reservoir exploration data shows that the corrosion conditions of Wushi oilfield are similar to those of existing reservoirs. After detecting and analyzing the water quality of Wushi, it is found that the injection water of Wushi oilfield group has a certain degree of scaling, and the scaling amount increases with the increase of temperature. The main scaling types are Ca 2+ , Ba 2+ , Sr 2+ scale. The technical requirements and origin of the raw materials used in the examples are shown in Table 1.

[0064] Table 1 Technical requirements and origin of raw materials

[0065]

[0066] Example 1

[0067] Laboratory synthesis:

[0068] 1. Synthesis of polyaspartic acid derivative:

[0069] The synthesis principle diagram of polyaspartic acid derivative is shown in Figure 1 , and the product characterization result diagram is shown in Figure 2 .

[0070] The polyaspartic acid derivative comprises the following components by mass fraction: poly succinimide 266 parts, N-(3-aminopropyl) imidazole 50 parts, 2-amino-1,3-propanediol 37 parts, mercaptoethylamine 92 parts, NaOH 60 parts, and water 20 parts.

[0071] The synthesis steps are as follows: N-(3-aminopropyl) imidazole and water are added to a single-necked flask, shaken evenly, magnetically stirred for 10 min, heated to 60℃, poly succinimide is added, reacted for 6 h, 2-amino-1,3-propanediol, mercaptoethylamine and water are added to the flask, reacted for 12 h, and finally 20% NaOH is added dropwise and reacted for 6 h. The dropwise time of NaOH is <60 min.

[0072] 2. Synthesis of quaternary ammonium salt:

[0073] The synthesis principle diagram of quaternary ammonium salt is shown in Figure 3 , and the product characterization result diagram is shown in Figure 4 .

[0074] Quaternary ammonium salt includes the following mass fraction of components: dimethylaminoethyl methacrylate 157 parts, p-chloromethylstyrene 168 parts, acetone 81 parts.

[0075] The synthesis steps are: adding dimethylaminoethyl methacrylate, p-chloromethylstyrene and acetone in a three-necked flask, heating to 50°C refluxing and stirring for 6 h, separating acetone by reduced pressure distillation, and drying after extracting and purifying the remaining crude product with ether.

[0076] 3. Synthesis of corrosion and scale inhibitor:

[0077] The corrosion and scale inhibitor includes the following mass fraction of components: polyaspartic acid derivative 150 parts, quaternary ammonium salt 100 parts, sodium molybdate 30 parts, thiourea 50 parts, potassium iodide 5 parts, methanol 133 parts, and water 532.

[0078] The synthesis steps are: adding deionized water in a reaction kettle, starting stirring, adding corresponding dosage of potassium iodide, sodium molybdate and thiourea, adding methanol, heating to 35±5°C within 0.5 h and stirring for 1 h; then adding polyaspartic acid derivative and quaternary ammonium salt, and continuing stirring for 0.5 h to obtain the corrosion and scale inhibitor product.

[0079] Example 2

[0080] Pilot production:

[0081] 1. Preparation of corrosion and scale inhibitor

[0082] The synthesis formula table and production process sheet of polyaspartic acid derivative are shown in Table 2.

[0083] Table 2 Synthesis formula table and production process sheet of polyaspartic acid derivative

[0084]

[0085] The synthesis formula table and production process sheet of quaternary ammonium salt are shown in Table 3.

[0086] Table 3 Synthesis formula table and production process sheet of quaternary ammonium salt

[0087]

[0088] The synthesis formula table and production process sheet of corrosion and scale inhibitor are shown in Table 4.

[0089] Table 4 Synthesis formula table and production process sheet of corrosion and scale inhibitor

[0090]

[0091] 2. Compatibility experiment between drugs

[0092] (1) Compatibility experiment of corrosion and scale inhibitor with demulsifier HYP-121

[0093] A certain amount of corrosion and scale inhibitor stock solution was taken, and the currently widely used HYP-121 demulsifier stock solution was directly added dropwise into the corrosion inhibitor. Whether the mixed solution was clear and transparent, and whether there were chemical and physical changes were observed. The experimental results are shown in Table 1. Figure 5

[0094] (2) Compatibility experiment of corrosion and scale inhibitor with water clarifying agent HYQ-131

[0095] Due to the limitation of the mechanism of water clarifying agent, the original agent must have different degrees of influence on the corrosion and scale inhibitor. Therefore, a corrosion and scale inhibitor aqueous solution with a concentration of 1000 ppm was prepared. 100 ppm, 500 ppm, 1000 ppm and 5000 ppm of water clarifying agent HYQ-131 were added to the prepared aqueous solution, respectively. Whether emulsification, agent reaction, coagulation and other phenomena occurred was observed. The experimental results are shown in Table 2. Figure 6

[0096] (3) Compatibility experiment of corrosion and scale inhibitor with demulsifier HYP-121 and water clarifying agent HYQ-131

[0097] The oil-water sample was taken for compatibility experiment, the experimental temperature was set to 64℃, the observation time was set to 1 min, 3 min, 5 min, 10 min, 20 min, 30 min and 60 min, the dehydration volume of different drug concentrations at different time points was recorded, and the results are shown in Table 5; whether the demulsification effect of the demulsifier was affected was observed, and the results are shown in Table 6. Figure 7

[0098] Table 5 Dehydration volume in compatibility experiment of corrosion and scale inhibitor with demulsifier HYP-121 and water clarifying agent HYQ-131

[0099]

[0100] 3. Evaluation of corrosion and scale inhibition performance

[0101] The performance evaluation was carried out under the following conditions: Ca 2+ : 115 mg / L, Mg 2+ : 18 mg / L, Na + : 8025 mg / L, Fe 2+ : 1.6 mg / L, Cl - : 10768 mg / L, : 543 mg / L, ​​​2515 mg / L; temperature 80℃; flow rate: 1 m / s; CO2 partial pressure: 0.5 MPa; total pressure: 2.5 MPa.

[0102] Test standard: determination of scale inhibition performance refers to the standard for determination of scale inhibition performance of water treatment agent, calcium carbonate deposition method GB / T 16632-2019.

[0103] Table 6 Evaluation results of corrosion and scale inhibition performance

[0104]

[0105] Table 5 is the dehydration volume in the compatibility experiment of the corrosion and scale inhibitor, demulsifier HYP-121 and water clarifying agent HYQ-131. As shown in Table 5, after adding the demulsifier HYP-121 alone and adding the demulsifier HYP-121 and the water clarifying agent HYQ-131 at the same time, the dehydration volumes at 1 min, 3 min, 5 min, 10 min, 20 min, 30 min and 60 min do not change obviously, which indicates that the corrosion and scale inhibitor provided by the application has good compatibility with the demulsifier, the demulsifier and the water clarifying agent, and is uniformly dispersed after mixing without phase separation.

[0106] Table 6 is the evaluation results of the corrosion and scale inhibition performance of the corrosion and scale inhibitor. As shown in Table 6, the performance test results of the corrosion and scale inhibitor produced in the pilot production (Example 2) and the laboratory sample (Example 1) are not much different, and the reinspection is qualified. The corrosion rate of the product is small, the scale inhibition rate of calcium carbonate, calcium sulfate and barium sulfate can reach more than 90%, and the performance requirements of the corrosion and scale inhibitor are met.

[0107] Figure 1 is a synthesis principle diagram of the polyaspartic acid derivative. Figure 1 It can be known that the polyaspartic acid derivative provided by the application is modified by using three different functional groups of N-(3-aminopropyl) imidazole, 2-amino-1, 3-propanediol and mercaptoethylamine on the basis of poly succinimide.

[0108] Figure 2 is a product characterization result diagram of the polyaspartic acid derivative. Figure 2 It can be known that the strong absorption peaks at 1650 cm -1 and 1395 cm -1 are attributed to the stretching vibration absorption peaks of C-N in the carbonyl and amide bond, the stretching vibration absorption peaks of the carbon-carbon skeleton on the imidazole ring at 1109 cm -1 and 1084 cm -1 , the stretching vibration absorption peak of N-H at 3417 cm -1 , and the stretching vibration absorption peak of N-H at 641 cm -1The stretching vibration absorption peak of C-S bond. The O-H stretching vibration and O-H bending vibration form two characteristic peaks, which are in the range of 3500 cm -1 and 1600 cm -1 , and it can be seen that the application successfully utilizes N-(3-aminopropyl) imidazole, 2-amino-1,3-propanediol and mercaptoethylamine three different functional groups to modify polyaspartic acid to form polyaspartic acid derivatives.

[0109] Figure 3 The synthesis principle diagram of quaternary ammonium salt is shown. Figure 3 It can be known that the quaternary ammonium salt is prepared by taking dimethylaminoethyl methacrylate, p-chloromethylstyrene and acetone as raw materials, and the obtained product contains quaternary ammonium ion (R4N + ), alkyl, carbonyl, carbon-carbon double bond and other functional groups.

[0110] Figure 4 The product characterization result diagram of quaternary ammonium salt is shown. Figure 4 It can be known that 2900 cm -1 and 2970 cm -1 are the stretching vibration absorption peaks of saturated carbon-hydrogen bonds in methyl and methylene; 1465 cm -1 and 1637 cm -1 are the asymmetric stretching vibration absorption peaks of benzene rings; 1710 cm -1 is the stretching vibration absorption peak of carbonyl; 1161 cm -1 and 1306 cm -1 are the stretching vibration absorption peaks of C-O-C; 915 cm -1 , 992 cm -1 are the bending vibration absorption peaks of RCH=CH; 868 cm -1 is the bending vibration absorption peak of R2C=CH2, so the quaternary ammonium salt shown in the formula is prepared by taking dimethylaminoethyl methacrylate, p-chloromethylstyrene and acetone as raw materials. Figure 3

[0111] Figure 5 The compatibility test comparison diagram of corrosion and scale inhibitor and demulsifier HYP-121 is shown. Figure 5 (a) only corrosion and scale inhibitor, Figure 5 (b) corrosion and scale inhibitor + demulsifier HYP-121. Figure 5 It can be known that the corrosion and scale inhibitor and the demulsifier HYP-121 have no chemical reaction and have good compatibility.

[0112] Figure 6 The compatibility test comparison diagram of corrosion and scale inhibitor and water clarifying agent HYQ-131 is shown. Figure 6 ​(a) 1000 ppm corrosion and scale inhibitor, Figure 6 (b) 1000 ppm corrosion and scale inhibitor + 100 ppm water clarifier HYQ-131, Figure 6 (c) 1000 ppm corrosion and scale inhibitor + 500 ppm water clarifier HYQ-131, Figure 6 (d) 1000 ppm corrosion and scale inhibitor + 1000 ppm water clarifier HYQ-131, Figure 6 (e) 1000 ppm corrosion and scale inhibitor + 5000 ppm water clarifier HYQ-131. Figure 6 As can be seen from (a), the corrosion and scale inhibitor is a water-soluble corrosion inhibitor, and 1000 ppm of the water-soluble corrosion inhibitor solution is transparent. Figure 6 In (c), 500 ppm of the water clarifier is added, and slight emulsification occurs, and there is no obvious change in physical properties and coagulation. Figure 7 In (d), when the water clarifier is added to more than 1000 ppm, emulsification is obvious, and there is no obvious change in physical properties and coagulation after standing for 1 day. However, the addition of 1000 ppm of the corrosion and scale inhibitor and 1000 ppm of the water clarifier in the field is an extreme abnormal phenomenon, and therefore the corrosion and scale inhibitor and the water clarifier HYQ-131 have good compatibility at a low concentration.

[0113] Figure 7 A comparison chart for the compatibility test of the corrosion and scale inhibitor and the demulsifier HYP-121 and the water clarifier HYQ-131. Figure 7 The pilot samples from left to right are: a field oilfield water sample, 40 ppm of the demulsifier HYP-121, 40 ppm of the demulsifier HYP-121 + 50 ppm of the corrosion and scale inhibitor, 40 ppm of the demulsifier HYP-121 + 50 ppm of the corrosion and scale inhibitor + 20 ppm of the water clarifier HYQ-131. ​ As can be seen, the combined use of the corrosion and scale inhibitor, the demulsifier HYP-121 and the water clarifier HYQ-131 used in the field does not affect the demulsification effect of the demulsifier, and has good compatibility.

[0114] As can be seen, the corrosion and scale inhibitor provided by the application, compared with the laboratory sample, the pilot product reinspection is qualified, the corrosion rate of the product is small, the scale inhibition rate is high, and the performance requirements of the corrosion and scale inhibitor are met. The compatibility with the demulsifier HYP-121 and the water clarifier HYQ-131 used in the field is good, and the performance of other reagents is not affected, and the corrosion and scale inhibitor can be better applied to the oilfield water system.

Claims

1. A corrosion and scale inhibitor, characterized in that, The product comprises the following components in parts by weight: 140-160 parts of polyaspartic acid derivative, 95-105 parts of quaternary ammonium salt, 25-35 parts of sodium molybdate, 45-55 parts of thiourea, 3-7 parts of potassium iodide, and 600-700 parts of solvent; the polyaspartic acid derivative comprises the following components in parts by weight: 250-280 parts of polysuccinimide, 45-55 parts of N-(3-aminopropyl)imidazolium, 85-100 parts of mercaptoethylamine, 30-40 parts of 2-amino-1,3-propanediol, 55-65 parts of alkali solution, and 15-30 parts of water; the quaternary ammonium salt comprises the following components in parts by weight: 150-170 parts of dimethylaminoethyl methacrylate, 160-180 parts of p-chloromethylstyrene, and 70-90 parts of acetone.

2. The corrosion and scale inhibitor according to claim 1, characterized in that, The solvent includes organic solvents and water; And / or, the ratio of the organic solvent to water is 1:(3~5); And / or, the organic solvent includes at least one of methanol, ethanol, acetone, ethyl acetate, dimethyl sulfoxide, diethyl ether, and acetonitrile.

3. The corrosion and scale inhibitor according to claim 1, characterized in that, The alkaline source of the alkaline solution is an alkali metal hydroxide; And / or, the mass fraction of the alkaline solution is 15 to 25 wt%.

4. A method for preparing the corrosion and scale inhibitor according to any one of claims 1 to 3, characterized in that, Includes the following steps: (1) Prepare polyaspartic acid derivatives and quaternary ammonium salts respectively; (2) Potassium iodide, sodium molybdate, thiourea, organic solvent, polyaspartic acid derivative, quaternary ammonium salt and water are mixed to obtain corrosion and scale inhibitor.

5. The method for preparing a corrosion and scale inhibitor according to claim 4, characterized in that, In step (1), the preparation of the polyaspartic acid derivative includes the following steps: A1. Mix N-(3-aminopropyl)imidazol with water, stir, and heat; A2. Add polysuccinimide, mix, and react; A3. Add 2-amino-1,3-propanediol, mercaptoethylamine and water, mix and react; A4. Add alkali solution, mix, react, and obtain polyaspartic acid derivative.

6. The method for preparing a corrosion and scale inhibitor according to claim 4, characterized in that, In step (1), the preparation of the quaternary ammonium salt includes the following steps: B1. Mix dimethylaminoethyl methacrylate, p-chloromethylstyrene, and acetone, heat to 45-55°C, and then react at a constant temperature. B2. Vacuum fractionation to separate and recover acetone, yielding quaternary ammonium salt.

7. The method for preparing a corrosion and scale inhibitor according to claim 5, characterized in that, In the preparation of the polyaspartic acid derivative, in step A1, the amount of water added is 50-60% of the total water volume; And / or, in step A4, the alkaline solution is added dropwise; And / or, in step A4, the alkaline solution is added over a time of < 60 min.

8. The application of the corrosion and scale inhibitor according to any one of claims 1 to 3 in oilfield water systems.

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