Corrosion inhibitor suitable for high-salt and high-chlorine working conditions and preparation method thereof

Abstract

The application discloses a kind of corrosion inhibitor suitable for high salt high chlorine working condition, including the following weight parts of components: benzyl alkyl methyl ammonium chloride 7~16 parts, trioleate 3~7 parts, surfactant 2~5 parts, organic urea promoter 5~12 parts, buffer 6~15 parts, water 20~40 parts, the weight ratio of benzyl alkyl methyl ammonium chloride, trioleate, surfactant is 1:(0.42~0.55):(0.28~0.35).The corrosion inhibitor has excellent corrosion inhibition effect for high salt high chlorine working condition;And meet the control requirements of the content of saprophytic bacteria (TGB) in water, the content of sulfate-reducing bacteria (SRB) and the content of iron bacteria (FB) after sterilization in SY / T 5757-2010 "Oilfield Injection Water Sterilizing Agent General Technical Conditions", and the on-site sterilization effect is excellent.

Description

Technical Field

[0001] This invention relates to the field of water treatment technology, specifically to a corrosion inhibitor suitable for high-salt and high-chlorine conditions and its preparation method. Background Technology

[0002] With the continuous exploitation of oilfields in my country, most of the country's onshore oilfields have entered the post-development stage, and the water content of produced fluids is constantly increasing, making bacterial growth and corrosion problems increasingly prominent. In particular, oilfields operating under high-salt and high-chlorine conditions contain more and more complex types of bacteria and other microorganisms. The intermediate or final products of microbial metabolism can accelerate the corrosion and damage of pipelines and surface equipment, causing huge economic losses and even major oilfield safety accidents.

[0003] Currently available oilfield corrosion inhibitors are not suitable for the more complex corrosive conditions under high-salt and high-chlorine environments. Their anti-corrosion effect is often unsatisfactory, requiring regular addition of inhibitors to maintain the anti-corrosion effect. Moreover, the bactericidal effect of existing oilfield corrosion inhibitors is limited, especially for oilfields with high-salt and high-chlorine conditions. They cannot effectively control the content of TGB, SRB, and FB bacteria simultaneously, falling far short of the bactericidal requirements for oilfields with high-salt and high-chlorine conditions.

[0004] Therefore, the urgent need to develop a corrosion inhibitor with multiple functions such as corrosion inhibition and bactericidal action suitable for high-salt and high-chlorine working conditions has become a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a corrosion inhibitor with multiple functions of corrosion inhibition and bactericidal action that is applicable to high-salt and high-chlorine working conditions.

[0006] The technical solution adopted by this invention to solve its technical problem is:

[0007] A corrosion inhibitor suitable for high-salt and high-chlorine working conditions, characterized in that it comprises the following components in parts by weight: 7-16 parts of benzyl alkyl methyl ammonium chloride, 3-7 parts of trioleate, 2-5 parts of surfactant, 5-12 parts of organic urea accelerator, 6-15 parts of buffer, and 20-40 parts of water, wherein the weight ratio of benzyl alkyl methyl ammonium chloride, trioleate, and surfactant is 1:(0.42-0.55):(0.28-0.35).

[0008] Preferably, the weight ratio of benzyl alkyl methyl ammonium chloride, trioleate, and surfactant is 1:0.48:0.33.

[0009] Preferably, the composition includes the following components in parts by weight: 10.5 parts benzyl alkyl methyl ammonium chloride, 5 parts trioleate, 3.5 parts surfactant, 8.5 parts organic urea accelerator, 10.5 parts buffer, and 30 parts water.

[0010] Preferably, the benzylalkylmethyl ammonium chloride is one or a combination of benzyl-hexadecyl-dimethyl ammonium chloride, benzyl-dodecyl-dimethyl ammonium chloride, and (3,4-dichlorophenyl)methyl-dodecyl-dimethyl ammonium chloride.

[0011] Preferably, the benzylalkylmethylammonium chloride is benzyl-hexadecyl-dimethylammonium chloride.

[0012] Preferably, the trioleate is one or a combination of glyceryl trioleate, gallogallate trioleate, sorbitol trioleate, and pentaerythritol trioleate.

[0013] Preferably, the trioleate is a glyceryl trioleate.

[0014] Preferably, the surfactant is a sulfonate surfactant.

[0015] Preferably, the sulfonate surfactant is one or a combination of sodium lignosulfonate, sodium dodecyl sulfonate, sodium dodecylbenzene sulfonate, and sodium dibutylnaphthalene sulfonate.

[0016] Preferably, the sulfonate surfactant is sodium dibutylnaphthalenesulfonate.

[0017] Preferably, the organic urea accelerator is one or a combination of thiourea, rutin, and urea.

[0018] Preferably, the organic urea accelerator is thiourea.

[0019] Preferably, it also includes 3 to 6 parts by weight of trimethoprim.

[0020] Preferably, it includes 4.5 parts by weight of trimethoprim.

[0021] Preferably, the trimethoprim is trimethoprim and / or dimethoprim.

[0022] Preferably, the trimethoprim is trimethoprim.

[0023] Technical effects:

[0024] Corrosion inhibitors using specific components and proportions of benzyl alkyl methyl ammonium chloride, trioleate, and surfactant exhibit excellent corrosion inhibition and bactericidal effects under high-salt and high-chlorine conditions. Specifically, when the components and proportions of benzyl alkyl methyl ammonium chloride, trioleate, and surfactant are fixed, on the one hand, the hydrophobic chains within their molecules intertwine, shortening the electrostatic distance between the hydrophilic head groups in the system, promoting the formation of an ordered phase within the system, and under the synergistic effect of the surfactant, rapidly disperse to the metal surface, forming a reinforcing protective film to prevent the diffusion of microorganisms and corrosive media to the metal surface, thus enhancing the corrosion inhibition effect; on the other hand, the reinforcing protective film can also, to a certain extent, hinder the aggregation of microorganisms on the metal surface, and the hydrophilic head groups of benzyl alkyl methyl ammonium chloride, after the electrostatic distance is compressed, have a better inhibitory and bactericidal effect.

[0025] As a preferred option, the corrosion inhibitor with a weight ratio of benzyl alkyl methyl ammonium chloride, trioleate, and surfactant of 1:0.48:0.33 exhibits better corrosion inhibition and bactericidal effects.

[0026] As a preferred option, trimethoprim is also included. As mentioned above, the reinforced protective film can hinder the aggregation of microorganisms on the metal surface to a certain extent. After electrostatic distance compression, the hydrophilic head group of benzyl alkyl methyl ammonium chloride, together with trimethoprim, can more easily adsorb bacteria and other microorganisms present in oil fields with high salt and high chlorine conditions, inhibit the growth of microorganisms, change the permeability of cell membranes and cause them to die, and significantly improve the bactericidal effect.

[0027] The present invention also provides a method for preparing a corrosion inhibitor, comprising the following steps: mixing the components and stirring evenly to prepare the corrosion inhibitor. Detailed Implementation

[0028] The present invention will now be described in further detail.

[0029] The following describes preferred embodiments of the invention. It should be understood that those skilled in the art can modify the invention described herein while still achieving its beneficial effects. Therefore, the following description should be understood as being of general knowledge to those skilled in the art and is not intended to limit the invention.

[0030] For clarity, not all features of the actual embodiments are described. In the following description, well-known functions and structures are not detailed in detail, as they would confuse the invention with unnecessary detail. It should be understood that in the development of any actual embodiment, numerous implementation details must be made to achieve the developer's specific objectives.

[0031] Example 1:

[0032] The corrosion inhibitor provided in Example 1 of the present invention comprises the following raw materials in parts by weight: 10.5 parts benzyl alkyl methyl ammonium chloride, 5 parts trioleate, 3.5 parts surfactant, 8.5 parts organic urea accelerator, 10.5 parts buffer, 30 parts water, and 4.5 parts trimethoprim, wherein the weight ratio of benzyl alkyl methyl ammonium chloride, trioleate, and surfactant is approximately 1:0.48:0.33.

[0033] The benzylalkylmethylammonium chloride is benzyl-hexadecyl-dimethylammonium chloride; the trioleate is glyceryl trioleate; the surfactant is sodium dibutylnaphthalenesulfonate; the organic urea accelerator is thiourea; the trimethoprim is trimethoprim; there are no particular limitations on the buffer used, and various oilfield corrosion inhibitor buffers well known to those skilled in the art can be used, such as sodium citrate.

[0034] The preparation method of the above corrosion inhibitor includes the following steps: adding benzylalkylmethylammonium chloride, trioleate, surfactant, organic urea accelerator and remaining raw materials to water and stirring until uniform.

[0035] Example 2:

[0036] The corrosion inhibitor provided in Example 2 of the present invention comprises the following raw materials in parts by weight: 7 parts benzyl alkyl methyl ammonium chloride, 3 parts trioleate, 2 parts surfactant, 5 parts organic urea accelerator, 6 parts buffer, 20 parts water, and 3 parts trimethoprim. The weight ratio of benzyl alkyl methyl ammonium chloride, trioleate, and surfactant is approximately 1:0.42:0.28.

[0037] The benzylalkylmethylammonium chloride is benzyl-hexadecyl-dimethylammonium chloride; the trioleate is glyceryl trioleate; the surfactant is sodium dibutylnaphthalenesulfonate; the organic urea accelerator is thiourea; the trimethoprim is trimethoprim; there are no particular limitations on the buffer used, and various oilfield corrosion inhibitor buffers well known to those skilled in the art can be used, such as sodium citrate.

[0038] The preparation method of the above corrosion inhibitor is the same as in Example 1.

[0039] Example 3:

[0040] The corrosion inhibitor provided in Example 3 of the present invention comprises the following raw materials in parts by weight: 16 parts benzyl alkyl methyl ammonium chloride, 7 parts trioleate, 5 parts surfactant, 12 parts organic urea accelerator, 15 parts buffer, 40 parts water, and 6 parts trimethoprim.

[0041] The benzylalkylmethylammonium chloride is benzyl-hexadecyl-dimethylammonium chloride; the trioleate is glyceryl trioleate; the surfactant is sodium dibutylnaphthalenesulfonate; the organic urea accelerator is thiourea; the trimethoprim is trimethoprim; there are no particular limitations on the buffer used, and various oilfield corrosion inhibitor buffers well known to those skilled in the art can be used, such as sodium citrate.

[0042] The preparation method of the above corrosion inhibitor is the same as in Example 1.

[0043] Example 4:

[0044] Example 4 of the present invention provides a corrosion inhibitor, the specific implementation of which is similar to that of Example 1, except that the benzylalkylmethylammonium chloride is replaced with dodecyltrimethylammonium chloride.

[0045] Example 5:

[0046] Example 5 of the present invention provides a corrosion inhibitor, the specific implementation of which is similar to that of Example 1, except that the amount of trioleate is 0.

[0047] Example 6:

[0048] Example 6 of the present invention provides a corrosion inhibitor, the specific implementation of which is similar to that of Example 1, except that the amount of surfactant is 0.

[0049] Example 7:

[0050] Example 7 of the present invention provides a corrosion inhibitor, the specific implementation of which is similar to that of Example 1, except that the amount of trioleate is 4.2 parts. In this Example 7, the weight ratio of benzyl alkyl methyl ammonium chloride, trioleate, and sulfonate surfactant is 1:0.4:0.33, which is not within the range of 1:(0.42~0.55):(0.28~0.35).

[0051] Example 8:

[0052] Example 8 of the present invention provides a corrosion inhibitor, the specific implementation of which is similar to that of Example 1, except that the amount of trioleate is 6.3 parts. In this Example 8, the weight ratio of benzylalkylmethylammonium chloride, trioleate, and sulfonate surfactant is 1:0.6:0.33, which is not within the range of 1:(0.42-0.55):(0.28-0.35).

[0053] Example 9:

[0054] Example 9 of the present invention provides a corrosion inhibitor, the specific implementation of which is similar to that of Example 1, except that the surfactant is present in 2.6 parts. In Example 9, the weight ratio of benzylalkylmethylammonium chloride, trioleate, and sulfonate surfactant is 1:0.47:0.24, which is not within the range of 1:(0.42-0.55):(0.28-0.35).

[0055] Example 10:

[0056] Example 10 of the present invention provides a corrosion inhibitor, the specific implementation of which is similar to that of Example 1, except that the surfactant is present in 4 parts.

[0057] Performance evaluation:

[0058] Performance testing: According to GB / T18175-2000 "Determination of corrosion inhibition performance of water treatment agents - Rotary plate method", oil-water mixture samples directly taken from the bottom of the Karamay oilfield well (belonging to high salt and high chlorine conditions) were divided into 12 portions as experimental media for later use. At 45℃, the corrosion inhibitors obtained in Examples 1 to 10, commercially available oilfield corrosion inhibitors and water samples were added to the oil-water mixture samples. The A3 steel plates were immersed in the experimental media using an RCC-Ⅰ type rotary plate corrosion tester. After 72 hours, the plates were taken out and the surface condition of the steel plates was observed. The results were recorded in Table 1.

[0059] Table 1. Results of corrosion inhibition performance test

[0060]

[0061]

[0062] The corrosion inhibitors obtained in Examples 1-3 meet the control requirements of SY / T 5757-2010 "General Technical Conditions for Bactericides in Oilfield Injection Water" for the content of saprophytic bacteria (TGB), sulfate reoxidizing bacteria (SRB), and iron bacteria (FB) in the water after sterilization under high salt and high chlorine conditions, and have excellent sterilization effect on site.

[0063] In a preferred embodiment, it further includes 1 to 2 parts of an adjuvant.

[0064] In a more preferred embodiment, 1.5 parts of an adjuvant are also included.

[0065] The present invention does not impose any particular limitation on the additives, and various corrosion inhibitors for resins, such as antioxidants, can be selected according to the actual situation and those skilled in the art can choose them.

[0066] The details of each component are as follows:

[0067] Benzyl-hexadecyl-dimethylammonium chloride (CAS No. 122-18-9), benzyl-dodecyl-dimethylammonium chloride (CAS No. 139-07-1), (3,4-dichlorophenyl)methyl-dodecyl-dimethylammonium chloride (CAS No. 102-30-7); glyceryl trioleate (CAS No. 122-32-7), galloyl gallate trioleate (CAS No. 17048-39-4), dehydrated sorbitol trioleate (CAS No. 26266-58-0), pentaerythritol trioleate Ester (CAS No. 39874-62-9); Sodium lignosulfonate (CAS No. 8061-51-6), Sodium dodecyl sulfonate (CAS No. 2386-53-0), Sodium dodecylbenzene sulfonate (CAS No. 25155-30-0), Sodium dibutylnaphthalene sulfonate (CAS No. 25417-20-3); Thiourea (CAS No. 62-56-6); Trimethoprim (CAS No. 738-70-5), Dimethoprim (CAS No. 5355-16-8);

[0068] The foregoing has shown and described the basic principles, main features, and advantages of the present invention; therefore, the above descriptions are merely embodiments of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are only principles of the present invention. The present invention also includes various equivalent changes and modifications without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A corrosion inhibitor suitable for high-salt and high-chlorine operating conditions, characterized in that, The product comprises the following components in parts by weight: 7-16 parts benzyl alkyl methyl ammonium chloride, 3-7 parts trioleate, 2-5 parts surfactant, 5-12 parts organic urea accelerator, 6-15 parts buffer, and 20-40 parts water, wherein the weight ratio of benzyl alkyl methyl ammonium chloride, trioleate, and surfactant is 1:0.48:0.33; and also comprises 4.5 parts by weight of trimethoprim. The benzylalkylmethylammonium chloride is benzyl-hexadecyl-dimethylammonium chloride, the trioleate is glyceryl trioleate, the surfactant is sodium dibutylnaphthalenesulfonate, the organic urea accelerator is thiourea, and the trimethoprim is trimethoprim.

2. A method for preparing the corrosion inhibitor as described in claim 1, characterized in that, The process includes the following steps: mixing the components and stirring until homogeneous to prepare the corrosion inhibitor.

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