Efficient environment-friendly chemical paraffin remover and inhibitor

Abstract

The invention belongs to the technical field of oil field gathering and transportation, and discloses an efficient environment-friendly chemical paraffin remover and inhibitor which comprises the following components in percentage by weight: 15-50% of polyoxymethylene dimethyl ether, 20-40% of methyl p-hydroxybenzoate, 1-5% of a stabilizer and 1-2% of a surfactant. The preparation method comprises the following steps: S1, firstly preparing methyl p-hydroxybenzoate, and putting a finished product into a reaction kettle; s2, adding polyoxymethylene dimethyl ether into the reaction kettle, heating to 40-50 DEG C, and stirring for 0.5-1 hour; s3, adding a stabilizer, and stirring for 0.5-1 hour; s4, the surfactant is added and stirred for 0.5-1 h to obtain a finished product, the defects that an existing paraffin remover and inhibitor is large in toxicity, not ideal in effect and the like are overcome through a chemical method, the paraffin dissolving rate of the product is larger than 0.016 g.min <-1 >, and the product does not contain sulfur, chlorine, phosphorus and other harmful elements which are prone to poisoning a crude oil refining catalyst and corroding equipment.

Description

Technical Field

[0001] The invention belongs to the technical field of oilfield gathering and transportation, relates to the technical field of oilfield gathering and transportation wax removal and prevention chemicals, and specifically relates to a high-efficiency and environment-friendly chemical wax removal and prevention agent. Background Art

[0002] Waxing of crude oil is a thorny issue in the process of oilfield development. During crude oil extraction, under the influence of environmental changes, paraffin molecules will crystallize out of crude oil and aggregate and deposit on the surface of equipment (such as sucker rods, pump impellers, and gathering and transportation pipelines), resulting in an increase in the workload of production equipment, a decrease in the effective inner diameter of the pipeline, and an increase in the flow resistance of crude oil, which in turn shortens the service life of equipment, reduces pipeline transportation efficiency, and increases energy consumption in the production process. In severe cases, pipelines may be blocked, causing production stoppages, resulting in huge economic losses and waste of resources. Chemical wax removers and wax preventers can destroy the structure of wax crystals, interfere with wax crystal aggregation, change the properties of wax crystals and wax deposits on the surface, and dissolve and peel off wax deposits, and flush them away through oil flow. However, the common wax removers and wax preventers on the market currently contain highly toxic chemical components, which may cause pollution to water bodies, soil, and ecosystems, and have limited effects in dissolving highly crystalline paraffin, resulting in the inability to completely remove the wax layer.

[0003] Therefore, improving the environmental protection and high efficiency of chemical wax removers and paraffin inhibitors is of great significance to improving oilfield production efficiency, ensuring stable oilfield operation, and protecting the environment in line with the needs of sustainable development. Summary of the invention

[0004] In view of the problems raised by the above background technology, the purpose of the present invention is to provide a highly efficient and environmentally friendly chemical wax removal and prevention agent.

[0005] In order to achieve the above technical objectives, the technical solution adopted by the present invention is as follows:

[0006] An efficient and environmentally friendly chemical wax remover and wax preventer, which comprises the following components in terms of weight percentage: 15-50% polyoxymethylene dimethyl ether, 20-40% methyl p-hydroxyphenyl acrylate, 1-5% stabilizer and 1-2% surfactant;

[0007] Its preparation method is:

[0008] S1, first prepare methyl p-hydroxyphenylacrylate and put the finished product into a reactor;

[0009] S2, add polyoxymethylene dimethyl ether into the reaction kettle, heat to 40-50°C, and stir for 0.5-1h;

[0010] S3, add stabilizer and stir for 0.5-1h;

[0011] S4. Add surfactant and stir for 0.5 to 1 hour to obtain the finished product.

[0012] It is further defined that the structural formula of the polyoxymethylene dimethyl ether is CH3O(CH2O)nCH3, wherein n is 1 to 4. The polyoxymethylene dimethyl ether is a low-toxic, low-pollution chemical with excellent wax-dissolving ability. The ether bonds and methoxy groups in its molecular structure make it polar, and it can interact with the non-polar hydrocarbon chain part in the paraffin molecule, thereby dissolving the paraffin and dispersing the dissolved paraffin particles into a stable suspension, thereby avoiding the re-aggregation and deposition of paraffin in the pipeline or wellbore, and can be applied to a variety of working conditions, and can maintain certain performance in both high and low temperature environments.

[0013] It is further defined that the synthesis steps of the methyl p-hydroxyphenylacrylate are:

[0014] S1, adding p-hydroxybenzyl alcohol and acrylic acid into a reaction kettle at a molar ratio of 1:1.1-1.5;

[0015] S2, adding stannous octoate as a catalyst to the reactor, wherein the amount added is calculated based on the mass of p-hydroxybenzyl alcohol, and the proportion thereof is controlled at 0.5% to 5%;

[0016] S3, adding water-carrying toluene to the reactor, the amount of which is calculated based on the sum of the mass of p-hydroxybenzyl alcohol and acrylic acid, and the ratio is controlled at 40% to 60%;

[0017] S4, heating to 105-135°C, reacting for 1-4h;

[0018] S5, distilling to remove unreacted acrylic acid and water-carrying agent, and then filtering to remove the catalyst to obtain methyl p-hydroxyphenylacrylate;

[0019] Methyl parahydroxyphenylacrylate has low toxicity and good biodegradability. It is an environmentally friendly wax remover and inhibitor ingredient. Its molecular structure includes hydroxyl and ester groups, which can interact with the non-polar long hydrocarbon chains in paraffin, effectively dissolve and break the structure of paraffin crystals, and inhibit the crystallization and deposition of paraffin.

[0020] It is further defined that the stabilizer is a polyoxyethylene ether compound, which is obtained by mixing commercially available AEO-3 and AEO-8 in a mass ratio of 1:1. Polyoxyethylene ether compounds, such as fatty alcohol polyoxyethylene ether, have high stability. The ether bonds in the molecules of such compounds are not easily destroyed by acids and alkalis, so they can maintain a stable structure in aqueous solution and are not prone to chemical changes. This stability enables polyoxyethylene ether compounds to maintain their performance under various environmental conditions, thereby effectively playing the role of stabilizers.

[0021] It is further defined that the surfactant is a demulsifier, including one or more of alkylphenol polyoxyethylene ether demulsifiers and OP-10. Alkylphenol polyoxyethylene ether demulsifiers, as a kind of polyoxyethylene nonionic surfactant, have excellent penetration, decontamination, wetting and emulsification effects. Such demulsifiers have high chemical stability and are not easily destroyed by strong acids and alkalis, so they can maintain their performance in various complex environments. When used as demulsifiers, they can effectively destroy the stable structure in the emulsion and separate the oil and water, thereby playing an important role in various industrial applications, such as crude oil demulsification in the petroleum industry;

[0022] As a kind of alkylphenol polyoxyethylene ether, OP-10 has a wider range of applications. It not only has excellent leveling, emulsifying, wetting, diffusion and antistatic properties, but is also resistant to acid, alkali, salt, hard water, and easily soluble in water. It can be mixed with various surfactants and dyestuffs. This makes OP-10 widely used in synthetic fiber oils, dispersants and leveling agents in bleaching and dyeing, oil field foaming agents, wetting agents and retarders, metal cleaning agents and other fields. In addition, OP-10 also has good washing and decontamination capabilities and is an important ingredient in civil and industrial detergents.

[0023] The beneficial effects of the present invention are as follows:

[0024] The present invention uses a chemical method to solve the shortcomings of existing wax removers and wax inhibitors, such as high toxicity and unsatisfactory effects.

[0025] The wax dissolving agent of the present invention has a strong dissolving effect on wax hydrocarbons in crude oil, prevents the formation of wax crystal nuclei, effectively destroys the three-dimensional network structure of paraffin crystals, and prevents wax crystals from gathering on the surfaces of the oil pipes and oil rods through its cleaning effect on the oil pipe walls and oil rod surfaces, thereby reducing the resistance of pipeline transportation and reducing production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The present invention can be further illustrated by means of non-limiting examples given in the accompanying drawings;

[0027] Figure 1 This is a schematic flow chart of an embodiment of a highly efficient and environmentally friendly chemical wax remover and wax inhibitor according to the present invention; DETAILED DESCRIPTION

[0028] In order to enable those skilled in the art to better understand the present invention, the technical solution of the present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0029] like Figure 1 As shown, the high-efficiency and environmentally friendly chemical wax remover and wax inhibitor of the present invention comprises the following components in terms of weight percentage: 15-50% of polymethoxy dimethyl ether, 20-40% of methyl p-hydroxyphenyl acrylate, 1-5% of stabilizer and 1-2% of surfactant;

[0030] Its preparation method is:

[0031] S1, first prepare methyl p-hydroxyphenylacrylate and put the finished product into a reactor;

[0032] S2, add polyoxymethylene dimethyl ether into the reaction kettle, heat to 40-50°C, and stir for 0.5-1h;

[0033] S3, add stabilizer and stir for 0.5-1h;

[0034] S4. Add surfactant and stir for 0.5 to 1 hour to obtain the finished product.

[0035] The preferred structural formula of polyoxymethylene dimethyl ether is CH3O(CH2O)nCH3, wherein n is 1 to 4. Polyoxymethylene dimethyl ether is a low-toxic, low-polluting chemical with excellent wax-dissolving ability. The ether bonds and methoxy groups in its molecular structure make it polar, and it can interact with the non-polar hydrocarbon chain part in the paraffin molecule, thereby dissolving the paraffin and dispersing the dissolved paraffin particles into a stable suspension, thereby avoiding the re-aggregation and deposition of paraffin in the pipeline or wellbore. It is also applicable to a variety of working conditions and can maintain certain performance in both high and low temperature environments.

[0036] The preferred synthesis steps of methyl p-hydroxyphenylacrylate are:

[0037] S1, adding p-hydroxybenzyl alcohol and acrylic acid into a reaction kettle at a molar ratio of 1:1.1-1.5;

[0038] S2, adding stannous octoate as a catalyst to the reactor, wherein the amount added is calculated based on the mass of p-hydroxybenzyl alcohol, and the proportion thereof is controlled at 0.5% to 5%;

[0039] S3, adding water-carrying toluene to the reactor, the amount of which is calculated based on the sum of the mass of p-hydroxybenzyl alcohol and acrylic acid, and the ratio is controlled at 40% to 60%;

[0040] S4, heating to 105-135°C, reacting for 1-4h;

[0041] S5, distilling to remove unreacted acrylic acid and water-carrying agent, and then filtering to remove the catalyst to obtain methyl p-hydroxyphenylacrylate;

[0042] Methyl parahydroxyphenylacrylate has low toxicity and good biodegradability. It is an environmentally friendly wax remover and inhibitor ingredient. Its molecular structure includes hydroxyl and ester groups, which can interact with the non-polar long hydrocarbon chains in paraffin, effectively dissolve and break the structure of paraffin crystals, and inhibit the crystallization and deposition of paraffin.

[0043] The preferred stabilizer is a polyoxyethylene ether compound, which is obtained by mixing commercially available AEO-3 and AEO-8 at a mass ratio of 1:1. Polyoxyethylene ether compounds, such as fatty alcohol polyoxyethylene ether, are highly stable. The ether bonds in the molecules of such compounds are not easily destroyed by acids or alkalis, so they can maintain a stable structure in aqueous solution and are not prone to chemical changes. This stability enables polyoxyethylene ether compounds to maintain their performance under various environmental conditions, thereby effectively playing the role of a stabilizer.

[0044] Preferably, the surfactant is a demulsifier, including one or more of alkylphenol polyoxyethylene ether demulsifiers and OP-10. Alkylphenol polyoxyethylene ether demulsifiers, as a kind of polyoxyethylene nonionic surfactant, have excellent penetration, decontamination, wetting and emulsification effects. Such demulsifiers have high chemical stability and are not easily destroyed by strong acids and alkalis, so they can maintain their performance in various complex environments. When used as demulsifiers, they can effectively destroy the stable structure in the emulsion and separate the oil and water, thereby playing an important role in various industrial applications, such as crude oil demulsification in the petroleum industry;

[0045] As a kind of alkylphenol polyoxyethylene ether, OP-10 has a wider range of applications. It not only has excellent leveling, emulsifying, wetting, diffusion and antistatic properties, but is also resistant to acid, alkali, salt, hard water, and easily soluble in water. It can be mixed with various surfactants and dyestuffs. This makes OP-10 widely used in synthetic fiber oils, dispersants and leveling agents in bleaching and dyeing, oil field foaming agents, wetting agents and retarders, metal cleaning agents and other fields. In addition, OP-10 also has good washing and decontamination capabilities and is an important ingredient in civil and industrial detergents.

[0046] Embodiment 1:

[0047] Take 35% of polyoxymethylene dimethyl ether, 30% of methyl parahydroxyphenyl acrylate, 3% of stabilizer and 1.5% of surfactant;

[0048] p-Hydroxybenzyl alcohol and acrylic acid are added into a reactor in a molar ratio of 1:1.3, stannous octoate of 3.5% by weight of p-hydroxybenzyl alcohol is added as a catalyst, and then toluene with a water content of 50% by weight of p-hydroxybenzyl alcohol and acrylic acid is added, the temperature is raised to 120°C, and the reaction is carried out for 2.5 hours. After the reaction is completed, unreacted acrylic acid and the water content are removed by distillation, and the catalyst is removed by filtration to obtain methyl p-hydroxybenzene acrylate. Then, polyoxymethylene dimethyl ether is added into the reactor, the temperature is raised to 45°C, and the mixture is stirred for 0.75h. Then, a stabilizer is added and the mixture is stirred for 0.75h. Finally, a surfactant is added and the mixture is stirred for 0.75h to obtain the finished product.

[0049] Embodiment 2:

[0050] Take 15% of polyoxymethylene dimethyl ether, 20% of methyl parahydroxyphenyl acrylate, 1% of stabilizer and 1% of surfactant;

[0051] p-Hydroxybenzyl alcohol and acrylic acid are added to a reactor in a molar ratio of 1:1.1, stannous octoate of 0.5% by weight of p-hydroxybenzyl alcohol is added as a catalyst, and then toluene with a water content of 40% by weight of p-hydroxybenzyl alcohol and acrylic acid is added, the temperature is raised to 105° C., and the reaction is carried out for 1 hour. After the reaction is completed, unreacted acrylic acid and the water content are removed by distillation, and the catalyst is removed by filtration to obtain methyl p-hydroxybenzene acrylate, and then polyoxymethylene dimethyl ether is added to the reactor, the temperature is raised to 40° C., and the mixture is stirred for 0.5 h, and then a stabilizer is added and stirred for 0.5 h, and finally a surfactant is added and stirred for 0.5 h to obtain a finished product;

[0052] Embodiment three:

[0053] Take 50% polyoxymethylene dimethyl ether, 40% methyl parahydroxyphenyl acrylate, 5% stabilizer and 2% surfactant;

[0054] p-Hydroxybenzyl alcohol and acrylic acid are added to a reactor in a molar ratio of 1:1.5, stannous octoate of 5% by weight of p-hydroxybenzyl alcohol is added as a catalyst, and then toluene with a water content of 60% by weight of p-hydroxybenzyl alcohol and acrylic acid is added, the temperature is raised to 135° C., and the reaction is carried out for 4 hours. After the reaction is completed, unreacted acrylic acid and the water content are removed by distillation, and the catalyst is removed by filtration to obtain methyl p-hydroxybenzene acrylate, and then polyoxyethylene dimethyl ether is added to the reactor, the temperature is raised to 50° C., and stirred for 1 hour, and then a stabilizer is added and stirred for 1 hour, and finally a surfactant is added and stirred for 1 hour to obtain a finished product;

[0055] Embodiment 4:

[0056] Take 40% polyoxymethylene dimethyl ether, 35% methyl p-hydroxyphenyl acrylate, 4% stabilizer and 1.7% surfactant;

[0057] p-Hydroxybenzyl alcohol and acrylic acid are added to a reactor in a molar ratio of 1:1.3, stannous octoate of 3.5% by weight of p-hydroxybenzyl alcohol is added as a catalyst, and then toluene with a water content of 50% by weight of p-hydroxybenzyl alcohol and acrylic acid is added, the temperature is raised to 120° C., and the reaction is carried out for 2.5 hours. After the reaction is completed, unreacted acrylic acid and the water content are removed by distillation, and the catalyst is removed by filtration to obtain methyl p-hydroxybenzene acrylate, and then polyoxymethylene dimethyl ether is added to the reactor, the temperature is raised to 45° C., and the mixture is stirred for 0.75 hours, and then a stabilizer is added and stirred for 0.75 hours, and finally a surfactant is added and stirred for 0.75 hours to obtain a finished product;

[0058] Embodiment five:

[0059] Take 25% of polyoxymethylene dimethyl ether, 20% of methyl parahydroxyphenyl acrylate, 2% of stabilizer and 1.3% of surfactant;

[0060] p-Hydroxybenzyl alcohol and acrylic acid are added to a reactor in a molar ratio of 1:1.3, stannous octoate of 3.5% by weight of p-hydroxybenzyl alcohol is added as a catalyst, and then toluene with a water content of 50% by weight of p-hydroxybenzyl alcohol and acrylic acid is added, the temperature is raised to 120° C., and the reaction is carried out for 2.5 hours. After the reaction is completed, unreacted acrylic acid and the water content are removed by distillation, and the catalyst is removed by filtration to obtain methyl p-hydroxybenzene acrylate, and then polyoxymethylene dimethyl ether is added to the reactor, the temperature is raised to 45° C., and the mixture is stirred for 0.75 hours, and then a stabilizer is added and stirred for 0.75 hours, and finally a surfactant is added and stirred for 0.75 hours to obtain a finished product;

[0061] Comparative Example 1:

[0062] The difference from Example 1 is that no polyoxymethylene dimethyl ether is added;

[0063] Comparative Example 2:

[0064] The paraffin removal and prevention agent of Comparative Example 2 is a traditional paraffin removal and prevention agent, and its main components are xylene, toluene, carbon tetrachloride and carbon disulfide. The above performance test data are shown in Table 1.

[0065] Table 1 Performance test results

[0066]

[0067] It can be learned from the table that, compared with Comparative Example 1, the wax removal and anti-wax agent containing polyoxymethylene dimethyl ether can effectively improve the anti-wax rate. By comparing Example 1 with Comparative Example 2, it can be seen that the wax removal and anti-wax agent of the present invention has a good effect.

[0068] The paraffin removing and preventing agent of the present invention contains polymethoxy dimethyl ether, and the ether bond and methoxy group in its molecular structure make it polar, which can interact with the non-polar hydrocarbon chain part in the paraffin molecule, thereby dissolving the paraffin, dispersing the dissolved paraffin particles into a stable suspension, and preventing the paraffin from re-aggregating and depositing in the pipeline or wellbore.

[0069] Furthermore, the wax dissolving rate of the product of the present invention is greater than 0.016 g·min -1 It does not contain harmful elements such as sulfur, chlorine, and phosphorus that can easily poison crude oil refining catalysts and corrode equipment, making it safe and environmentally friendly.

[0070] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the technology may modify or change the above embodiments without violating the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by those with ordinary knowledge in the technical field without departing from the spirit and technical ideas disclosed by the present invention should still be covered by the claims of the present invention.

Claims

1. A highly efficient and environmentally friendly chemical wax remover and inhibitor, characterized in that: The weight percentage meter includes the following components: 15-50% of polyoxymethylene dimethyl ether, 20-40% of methyl p-hydroxyphenyl acrylate, 1-5% of stabilizer and 1-2% of surfactant; Its preparation method is: S1, first prepare methyl p-hydroxyphenylacrylate and put the finished product into a reactor; S2, add polyoxymethylene dimethyl ether into the reaction kettle, heat to 40-50°C, and stir for 0.5-1h; S3, add stabilizer and stir for 0.5-1h; S4. Add surfactant and stir for 0.5 to 1 hour to obtain the finished product.

2. The highly efficient and environmentally friendly chemical wax remover and inhibitor according to claim 1, characterized in that: The structural formula of the polyoxymethylene dimethyl ether is CH3O(CH2O)nCH3, wherein n is 1-4.

3. The highly efficient and environmentally friendly chemical wax remover and inhibitor according to claim 1, characterized in that: The synthesis steps of the methyl p-hydroxyphenylacrylate are: S1, adding p-hydroxybenzyl alcohol and acrylic acid into a reaction kettle at a molar ratio of 1:1.1-1.5; S2, adding stannous octoate as a catalyst to the reactor, wherein the amount added is calculated based on the mass of p-hydroxybenzyl alcohol, and the proportion thereof is controlled at 0.5% to 5%; S3, adding water-carrying toluene to the reactor, the amount of which is calculated based on the sum of the mass of p-hydroxybenzyl alcohol and acrylic acid, and the ratio is controlled at 40% to 60%; S4, heating to 105-135°C, reacting for 1-4h; S5, distilling off unreacted acrylic acid and water-carrying agent, and then filtering off the catalyst to obtain methyl p-hydroxyphenylacrylate.

4. The highly efficient and environmentally friendly chemical wax remover and inhibitor according to claim 1, characterized in that: The stabilizer is a polyoxyethylene ether compound, which is obtained by mixing commercially available AEO-3 and AEO-8 in a ratio of 1:1 by mass.

5. The highly efficient and environmentally friendly chemical wax remover and inhibitor according to claim 4, characterized in that: The surfactant is a demulsifier, including one or more of alkylphenol polyoxyethylene ether demulsifiers and OP-10.

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