Corrosion inhibitor for ground gathering pipeline and preparation method thereof

Abstract

The application discloses a kind of ground gathering and transferring pipeline corrosion inhibitor, including the following components by weight percentage: corrosion inhibitor main agent 10-45%, bactericide 5-25%, oxygen scavenger 5-10% and solvent 40-55%.A kind of ground gathering and transferring pipeline corrosion inhibitor preparation method is also provided, including the following steps: (1) as needed in reaction kettle, then add ethanol, stirring is uniform, to obtain solvent;(2) corrosion inhibitor main agent, bactericide and oxygen scavenger are sequentially added to solvent, heated to 50-60 DEG C, uniformly stirred 0.5-1.5h after gradually cooling down, to obtain ground gathering and transferring pipeline corrosion inhibitor.The application can effectively reduce the cell number of sulfate-reducing bacteria and iron bacteria, can reduce the corrosion of microorganism to pipeline and play better corrosion inhibition effect, thereby effectively solve the problem that gathering and transferring pipeline laid on ground in different environments is easily corroded, especially easily corroded by microorganism.

Description

Technical Field

[0001] This invention belongs to the field of corrosion prevention technology for gathering and transportation pipelines in oil and gas field development, specifically relating to a corrosion inhibitor for surface gathering and transportation pipelines and its preparation method. Background Technology

[0002] Pipeline transportation is used in my country for transporting water, gas, and oil. Due to economic reasons, carbon steel is the most commonly used material for these pipelines, and its high pressure resistance and good machinability have led to its widespread use. However, carbon steel pipelines have poor corrosion resistance. Ground-based gathering and transportation pipelines are highly susceptible to corrosion and perforation after being exposed to wind, rain, and other environmental factors. For example, pipelines laid in dry areas are easily corroded by deposited sand and gravel; while those laid in humid and rainy areas are susceptible to erosion by moisture and acidic substances. Once pipelines transporting gas and oil are corroded, they pose significant safety hazards and cause substantial economic losses.

[0003] Current anti-corrosion measures for ground-laid gathering and transportation pipelines primarily target the corrosion and oxidation caused by sand, gravel, hydrogen sulfide, and carbon dioxide. However, what is often overlooked is that microorganisms are ubiquitous in both dry and humid environments, especially abundant in the soil surface. Research has found that iron bacteria and sulfate-reducing bacteria are the main culprits in the corrosion of carbon steel. In humid environments, iron bacteria can oxidize ferrous compounds, causing nodules on the pipe surface. The nodules create an anaerobic environment, forming oxygen concentration cells that accelerate the corrosion process. Other bacteria, such as acid-producing bacteria, can convert soluble sulfides or ammonia into sulfuric acid or nitric acid, lowering the local pH and further accelerating pipeline corrosion. Once transportation pipelines are corroded by microorganisms, it not only affects the safety of gas and oil transportation but also causes soil pollution.

[0004] Currently, corrosion inhibitors are commonly used to suppress pipeline corrosion, and the following related technologies have been proposed:

[0005] For example, patent document CN111850568A discloses a corrosion inhibitor for preventing scale and corrosion in oilfield surface gathering and transportation pipelines. The components of the corrosion inhibitor, by mass fraction, include 0.5 to 12 parts of a main agent, 0.1 to 10 parts of nano-silica, 1 to 14 parts of sodium tetraborate, 0.5 to 8 parts of tungstate, and 5 to 20 parts of α-mercaptolauric acid. The corrosion inhibitor also includes ethanol and water, and the mass ratio of the total mass of ethanol and water to the mass of the main agent is (12 to 92.9):(0.5 to 12). The main agent is rosin amine polyoxyethylene ether or rosin-based imidazoline quaternary ammonium salt.

[0006] For example, patent document CN104988511A discloses a corrosion inhibitor and its preparation method. The corrosion inhibitor includes: oleic acid imidazoline, wherein the mass content of oleic acid imidazoline is 30-40 parts; an oxygen scavenger, wherein the mass content of the oxygen scavenger is 5-10 parts; thiocyanate, wherein the mass content of the thiocyanate is 3-5 parts; glutaraldehyde, wherein the mass content of the glutaraldehyde is 10-15 parts; and water, wherein the mass content of the water is 30-50 parts.

[0007] While the aforementioned corrosion inhibitors all exhibit good corrosion inhibition effects, none of them take into account the corrosive effect of microorganisms on pipelines; that is, none of them can effectively suppress microbial erosion. Microorganisms grow and reproduce rapidly, and once corrosion occurs, it will cover a large area, also affecting the soil environmental balance near the eroded area, which is environmentally unfriendly.

[0008] Furthermore, if microbial corrosion occurs, repairs must ensure that iron bacteria and other microorganisms that corrode pipes are completely removed. However, current technology makes it difficult to determine whether the corrosion has been completely eliminated, and without protective measures, microorganisms can still proliferate. Therefore, in summary, there is an urgent need for a new corrosion inhibitor that can adapt to changing environments and effectively reduce microbial corrosion of pipes. Summary of the Invention

[0009] The purpose of this invention is to overcome the above-mentioned technical problems existing in the prior art and to provide a corrosion inhibitor for ground gathering and transportation pipelines and its preparation method. This invention can effectively reduce the number of sulfate-reducing bacteria and iron bacteria cells, and can reduce the corrosion of pipelines by microorganisms and play a better corrosion inhibition role, thereby effectively solving the problem that gathering and transportation pipelines laid on the ground in different environments are susceptible to corrosion, especially to microbial corrosion.

[0010] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0011] This invention provides a corrosion inhibitor for surface gathering and transmission pipelines, characterized in that it comprises the following components by weight percentage:

[0012] The composition consists of 10-45% corrosion inhibitor, 5-25% bactericide, 5-10% oxygen scavenger, and 40-55% solvent.

[0013] The sustained-release agent is a mixture of 3-anisidine amino-1,2,4-triazole phosphate and phosphonic acid.

[0014] The 3-anisidine amino-1,2,4-triazole phosphate is 6-25% by weight, and the phosphonic acid is 4-20%.

[0015] The bactericide is a mixture of a quaternary ammonium salt bactericide and aldehydes.

[0016] The aldehydes are composed of a mixture of glutaraldehyde and formaldehyde.

[0017] By weight percentage, the quaternary ammonium salt bactericide is 3-15%, the glutaraldehyde is 1-5%, and the formaldehyde is 1-5%.

[0018] The oxygen scavenger is thioaminourea, aminourea, or sodium sulfite.

[0019] The solvent is a mixture of ethanol and deionized water.

[0020] The ethanol is 12-20% by weight and the deionized water is 28-35%.

[0021] This invention also provides a method for preparing a corrosion inhibitor for surface gathering and transmission pipelines, characterized by comprising the following steps:

[0022] (1) Solvent preparation: Add deionized water to the reaction vessel as needed by weight percentage, then add ethanol and stir evenly to obtain the solvent;

[0023] (2) Preparation of corrosion inhibitor: The corrosion inhibitor, bactericide and oxygen remover are added to the solvent in sequence, heated to 50-60℃, stirred evenly for 0.5-1.5h and then gradually cooled down to obtain the corrosion inhibitor for ground gathering and transportation pipelines.

[0024] The advantages of using this invention are:

[0025] 1. The corrosion inhibitor of the present invention comprises a corrosion inhibitor, a bactericide, an oxygen scavenger, and a solvent. Among them,

[0026] Regarding the components: The corrosion inhibitor in the system prevents or slows down the corrosion of pipe materials by forming a passivating film on the metal surface, thus inhibiting corrosion. The bactericide kills or inhibits the growth of microorganisms (such as iron bacteria), and has advantages such as high efficiency, low toxicity, stability, low cost, and non-corrosiveness. The oxygen scavenger effectively consumes oxygen in the solution, preventing oxygen-absorbing corrosion. The solvent ensures that the aforementioned components are effectively dissolved in the corrosion inhibitor system, thereby enhancing the product's corrosion-inhibiting effect.

[0027] Regarding the mixing ratio: If the ratio of the corrosion inhibitor is too high, the product cost will be high, and it will also be difficult to mix evenly with other reagents. If the ratio of the corrosion inhibitor is too low, the product effect will be poor and it will not be able to inhibit corrosion. If the ratio of the bactericide is too high, the concentration will be high, which will not only kill the main corrosive microorganisms but also have a negative impact on other types of microorganisms. If the ratio of the bactericide is too low, it will not be able to effectively kill or inhibit the proliferation of iron bacteria and other microorganisms.

[0028] Regarding synergistic effects: The organophosphonates in the system form a protective film on the metal surface, which can inhibit corrosion. They also exhibit good chelation, dispersion, and lattice distortion effects on calcium carbonate, calcium sulfate, and calcium phosphate in water. The oxygen scavenger provides an oxygen-free or low-oxygen environment, which, combined with the corrosion inhibitor, can effectively prevent pipeline oxidation and rust. Therefore, there is a certain synergistic effect among these four components.

[0029] In addition, the corrosion inhibitor also has the following effects:

[0030] (1) All four components have low toxicity, which can achieve the effect of low toxicity of corrosion inhibitor.

[0031] (2) Oxygen scavengers provide an oxygen-free or low-oxygen environment and work with corrosion inhibitors to prevent pipe oxidation and rust. However, since iron bacteria live in an environment with low oxygen content, they can be inhibited by synergistic bactericides.

[0032] (3) The corrosion inhibitor forms a film on the metal surface, which can prevent rainwater or water vapor from eroding or corroding to a certain extent.

[0033] In summary, the corrosion inhibitor formulated by the above-mentioned specific proportions of components has the advantages of low toxicity, low volatility, non-decomposition, high chemical stability, and the ability to effectively reduce the number of sulfate-reducing bacteria and iron bacteria cells. In practical applications, it can effectively solve the problem of corrosion of gathering and transportation pipelines laid on the ground in different environments, especially the problem of microbial corrosion, by reducing the corrosion of pipelines by microorganisms.

[0034] 2. This invention specifies that the slow-release agent is a mixture of 3-anisidine amino-1,2,4-triazole phosphate and phosphonic acid. Since 3-anisidine amino-1,2,4-triazole phosphate still exhibits good corrosion inhibition for carbon steel in aqueous solution, the product maintains good corrosion inhibition even in humid and rainy conditions, thus making it suitable for variable environments.

[0035] 3. This invention specifies that the bactericide is a mixture of a quaternary ammonium salt bactericide and an aldehyde, and further specifies that the aldehyde is a mixture of glutaraldehyde and formaldehyde. Wherein,

[0036] Biquaternary ammonium salt bactericides are primarily antibacterial surfactants. They not only have bactericidal effects but also enhance the bactericidal activity of active ingredients. They also have a strong stripping effect on slime and can kill sulfate-reducing bacteria growing beneath slime. Glutaraldehyde is a non-ionic broad-spectrum bactericide, resistant to salt and hard water, and can be used in combination with other agents.

[0037] Formaldehyde acts as a protein coagulator in the system, directly affecting the amino, thiol, hydroxyl, and carboxyl groups of organic matter to generate methine derivatives, thereby destroying proteins and enzymes and causing microbial death.

[0038] Glutaraldehyde is a highly effective disinfectant. It kills bacteria by alkylating microbial proteins, sealing the outer layer of bacterial cells, and inactivating cellular enzymes. Furthermore, the bactericide formed by combining glutaraldehyde and quaternary ammonium salts easily penetrates the protective layer formed by grease and kills bacteria beneath it. It can kill both aerobic and anaerobic microorganisms, effectively control slime-forming bacteria, and kill sulfate-reducing bacteria and algae. Therefore, it cannot be replaced by other similar components.

[0039] 4. This invention specifies that the oxygen scavenger is thioaminourea, aminourea, or sodium sulfite. Sodium sulfite is a reducing agent that reacts with dissolved oxygen in water to form sodium sulfate. The free oxygen in the water is fixed by the reducing agent sodium sulfite and does not react with metallic iron, thus preventing pipeline corrosion. Thioaminourea and aminourea are commonly used in pesticides as intermediates in organic synthesis, and they exhibit a certain bactericidal effect when combined with fungicides. Using any of these components as an oxygen scavenger can achieve a good bacteriostatic effect when combined with fungicides.

[0040] 5. This invention specifies that the solvent is a mixture of ethanol and deionized water. Its advantages are that it has good solubility for various chemical components (it can dissolve a variety of organic and inorganic compounds), and it is also inexpensive and environmentally friendly. Detailed Implementation

[0041] This invention provides a corrosion inhibitor for surface gathering and transmission pipelines, comprising the following components by weight percentage:

[0042] The composition consists of 10-45% corrosion inhibitor, 5-25% bactericide, 5-10% oxygen scavenger, and 40-55% solvent.

[0043] The sustained-release agent is a mixture of 3-anisidine amino-1,2,4-triazole phosphate and phosphonic acid.

[0044] The 3-anisidine amino-1,2,4-triazole phosphate is 6-25% by weight, and the phosphonic acid is 4-20%.

[0045] The bactericide is a mixture of a quaternary ammonium salt bactericide and aldehydes.

[0046] The aldehydes are composed of a mixture of glutaraldehyde and formaldehyde.

[0047] By weight percentage, the quaternary ammonium salt bactericide is 3-15%, the glutaraldehyde is 1-5%, and the formaldehyde is 1-5%.

[0048] The oxygen scavenger is thioaminourea, aminourea, or sodium sulfite.

[0049] The solvent is a mixture of ethanol and deionized water.

[0050] The ethanol is 12-20% by weight and the deionized water is 28-35%.

[0051] This invention also provides a method for preparing a corrosion inhibitor for surface gathering and transmission pipelines, comprising the following steps:

[0052] (1) Solvent preparation: Add deionized water to the reaction vessel as needed by weight percentage, then add ethanol and stir until homogeneous to obtain the solvent.

[0053] (2) Preparation of corrosion inhibitor: The corrosion inhibitor, bactericide and oxygen remover are added to the solvent in sequence, heated to 50-60℃, stirred evenly for 0.5-1.5h and then gradually cooled down to obtain the corrosion inhibitor for ground gathering and transportation pipelines.

[0054] The corrosion inhibitor prepared using the above-mentioned specific proportions of components has low toxicity, low volatility, is not easily decomposed, and has high chemical stability. In practical applications, it can effectively reduce the number of sulfate-reducing bacteria and iron bacteria cells, thereby reducing microbial corrosion of pipelines and achieving a better corrosion inhibition effect. The invention will be described in detail below with reference to specific embodiments.

[0055] Example 1

[0056] In this embodiment, a 10 kg corrosion inhibitor is prepared as needed, which includes the following components by weight percentage: 10% corrosion inhibitor, 25% bactericide, 10% oxygen scavenger, and 55% solvent.

[0057] Furthermore, the specific composition and formulation of this corrosion inhibitor are shown in the table below:

[0058]

[0059] The preparation method of this corrosion inhibitor includes the following steps:

[0060] (1) Solvent preparation: Add deionized water to the reaction vessel as needed by weight percentage, then add ethanol and stir until homogeneous to obtain the solvent.

[0061] (2) Preparation of corrosion inhibitor: The corrosion inhibitor, bactericide and oxygen remover are added to the solvent in sequence, heated to 50°C, stirred evenly for 1.5 hours and then gradually cooled down to obtain the corrosion inhibitor for ground gathering and transportation pipelines.

[0062] Example 2

[0063] In this embodiment, a 20 kg corrosion inhibitor is prepared as needed, which includes the following components by weight percentage: 45% corrosion inhibitor, 5% bactericide, 5% oxygen scavenger, and 45% solvent.

[0064] Furthermore, the specific composition and formulation of this corrosion inhibitor are shown in the table below:

[0065]

[0066] The preparation method of this corrosion inhibitor is the same as the steps described in Example 1, except that when preparing the corrosion inhibitor, the temperature is raised to 60°C and stirred evenly for 0.5 hours.

[0067] Example 3

[0068] In this embodiment, a 50 kg corrosion inhibitor is prepared as needed, which includes the following components by weight percentage: 30% corrosion inhibitor, 20% bactericide, 10% oxygen scavenger, and 40% solvent.

[0069] Furthermore, the specific composition and formulation of this corrosion inhibitor are shown in the table below:

[0070]

[0071] The preparation method of this corrosion inhibitor is the same as the steps described in Example 1, except that when preparing the corrosion inhibitor, the temperature is raised to 55°C and stirred evenly for 1 hour.

[0072] Example 4

[0073] In this embodiment, 100 kg of corrosion inhibitor is prepared as needed, which includes the following components by weight percentage: 25% corrosion inhibitor, 12% bactericide, 8% oxygen scavenger and 55% solvent.

[0074] Furthermore, the specific composition and formulation of this corrosion inhibitor are shown in the table below:

[0075]

[0076] The preparation method of this corrosion inhibitor is the same as that described in Example 1, except that when preparing the corrosion inhibitor, the temperature is raised to 52°C and stirred evenly for 1.2 hours.

[0077] Example 5

[0078] In this embodiment, a 10 kg corrosion inhibitor is prepared as needed, which includes the following components by weight percentage: 30% corrosion inhibitor, 15% bactericide, 6% oxygen scavenger, and 49% solvent.

[0079] Furthermore, the specific composition and formulation of this corrosion inhibitor are shown in the table below:

[0080]

[0081] The preparation method of this corrosion inhibitor is the same as the steps described in Example 1, except that when preparing the corrosion inhibitor, the temperature is raised to 54°C and stirred evenly for 1 hour.

[0082] Example 6

[0083] In this embodiment, a 20 kg corrosion inhibitor is prepared as needed, which includes the following components by weight percentage: 25% corrosion inhibitor, 25% bactericide, 5% oxygen scavenger, and 50% solvent.

[0084] Furthermore, the specific composition and formulation of this corrosion inhibitor are shown in the table below:

[0085]

[0086] The preparation method of this corrosion inhibitor is the same as that described in Example 1, except that when preparing the corrosion inhibitor, the temperature is raised to 58°C and stirred evenly for 0.8 hours.

[0087] The present invention tested the corrosion inhibitors described in Examples 1-6, as follows:

[0088] Experimental conditions: Simulation period 30 days.

[0089] Examples 1-3 simulated a humid and rainy region A, with simulated rain every two days for 30 minutes each time, and soil samples were taken from region A.

[0090] Toxicity: Non-toxic.

[0091] Examples 4-6 simulated arid region B, with simulated sunlight once a day from 12:00 to 15:00, and soil samples were taken from region B.

[0092] Toxicity: Non-toxic.

[0093] The corrosion inhibition rate achieved by the corrosion inhibitors described in Examples 1-6 above under simulated field conditions is shown in the following table:

[0094]

[0095] Among them, the release rate of conventional corrosion inhibitors on the market is mostly between 70-80%. Compared with the test results in the table above, it can be clearly seen that the corrosion inhibitor of the present invention has a superior corrosion inhibition effect.

[0096] The above description is merely a specific embodiment of the present invention. Any feature disclosed in this specification may be replaced by other equivalent or similar features unless otherwise specified. All features or steps in all methods or processes disclosed may be combined in any way except for mutually exclusive features and / or steps.

Claims

1. A corrosion inhibitor for surface gathering and transmission pipelines, characterized in that, Includes the following components by weight percentage: The composition includes 10-45% corrosion inhibitor, 5-25% bactericide, 5-10% oxygen scavenger, and 40-55% solvent. The corrosion inhibitor is a mixture of 3-anisidine amino-1,2,4-triazole phosphate and phosphonic acid. By weight percentage, the 3-anisidineamino-1,2,4-triazole phosphate is 6-25%, and the phosphonic acid is 4-20%. The bactericide is a mixture of a quaternary ammonium salt bactericide and aldehydes; The aldehydes are a mixture of glutaraldehyde and formaldehyde; By weight percentage, the quaternary ammonium salt bactericide is 3-15%, the glutaraldehyde is 1-5%, and the formaldehyde is 1-5%.

2. The corrosion inhibitor for surface gathering and transmission pipelines according to claim 1, characterized in that: The oxygen scavenger is thioaminourea, aminourea, or sodium sulfite.

3. The corrosion inhibitor for surface gathering and transmission pipelines according to claim 1, characterized in that: The solvent is a mixture of ethanol and deionized water.

4. The corrosion inhibitor for surface gathering and transmission pipelines according to claim 3, characterized in that: The ethanol is 12-20% by weight and the deionized water is 28-35%.

5. A method for preparing a corrosion inhibitor for surface gathering and transmission pipelines according to any one of claims 1-4, characterized in that... Includes the following steps: (1) Solvent preparation: Add deionized water to the reaction vessel as needed, then add ethanol and stir until homogeneous to obtain the solvent; (2) Preparation of corrosion inhibitor: The corrosion inhibitor, bactericide and oxygen remover are added to the solvent in sequence, heated to 50-60℃, stirred evenly for 0.5-1.5h and then gradually cooled down to obtain the corrosion inhibitor for ground gathering and transportation pipelines.

Images