Asphalt dispersing and wax removing agent for oil extraction and preparation method of asphalt dispersing and wax removing agent

Abstract

The invention relates to an asphalt dispersing and wax removing agent for oil extraction. The problem that the actual effect is limited due to the fact that asphaltene and wax are singly dispersed or removed in an existing chemical removal method is mainly solved. The invention relates to an asphaltene cleaning agent which is characterized by comprising the following components in percentage by mass: 10%-20% of an asphaltene deposition inhibitor, 10%-20% of a surfactant, 1%-5% of a flash point improver and 55%-79% of an organic hydrocarbon solvent. The preparation method comprises the following steps: adding the asphaltene deposition inhibitor into the organic hydrocarbon solvent, stirring and dissolving, continuing to add the surfactant, stirring, adding the flash point improver, and stirring to enable the system to be dissolved and dispersed uniformly. The asphalt dispersing and wax removing agent for oil extraction can be used for dispersing and inhibiting precipitation of asphaltene in a crude oil extraction process, can also be used for preventing wax crystallization after light components continuously escape along with temperature and pressure reduction, and can be used for effectively removing precipitated wax, so that smooth oil flow in a well bottom stratum and a shaft is ensured, and energy loss is reduced.

Description

Technical field:

[0001] The invention relates to the field of chemical agents for oil field production, and in particular to an asphalt dispersing dewaxing agent for oil production and a preparation method thereof. Background technology:

[0002] During the oil production process and when some oil production technologies are applied, the balance between the asphaltene solution and the colloid system components in the oil reservoir will be destroyed, resulting in the deposition of heavy components such as asphaltene in the oil reservoir, wellbore and wellhead equipment. During the oil production process, as the temperature and pressure drop and the light components continue to escape, the wax dissolving capacity of the crude oil also decreases. When certain conditions are reached, the wax in the crude oil will precipitate, aggregate and deposit on the inner wall of the oil casing, the surface of the sucker rod, the pump and other equipment in the form of crystals, resulting in wax deposition in the oil well.

[0003] There are many methods for asphaltene wax removal at home and abroad, mainly mechanical removal technology, thermal removal technology, microbial removal technology and chemical removal technology. Mechanical removal method is to scrape asphaltene cement and crystalline wax with cutting tools. Mechanical removal method has low cost; but the effective removal period is short and the removal position is limited. Thermal removal method is to increase the liquid temperature of the sucker rod and tubing by heat energy, so that the ambient temperature is greater than the melting temperature of asphaltene wax, so as to achieve the purpose of removal. The application of thermal removal method is the most direct and the effect is the most significant; but this method consumes a lot of energy and the construction period is relatively long. If the production process is improper, it will also cause reservoir pollution. Microbial removal method is to use microorganisms to degrade long-chain hydrocarbon macromolecules or produce surfactants to reduce the interaction between crude oil and well wall, and reduce the blockage of rock pores by debris; microbial removal method has low operation cost and is environmentally friendly, but the production of biological enzymes is more complicated and the application conditions are more demanding. Chemical removal is the use of chemical agents to stabilize crude oil components to reduce the deposition of asphaltene and the crystallization of wax in crude oil, and effectively remove the crystallized wax scale; compared with other technologies, chemical removal technology has better advantages and is a commonly used removal method. However, the current chemical removal methods are all for the single dispersion or removal of asphaltene and wax, and the actual effect is limited; in the process of crude oil extraction, the precipitation and crystallization of asphaltene and wax are accompanied together. When dispersing asphaltene, wax deposition must be effectively prevented and removed. Summary of the invention:

[0004] The purpose of the present invention is to overcome the problem that the existing chemical removal methods in the background technology are all single dispersion or removal of asphaltene and wax, resulting in limited actual effects, and to provide an asphalt dispersing and wax removing agent for oil production. The asphalt dispersing and wax removing agent for oil production can not only disperse the asphaltene in the crude oil production process and inhibit the precipitation, but also prevent the crystallization of wax after the temperature and pressure drop and the continuous escape of light components, and effectively remove the wax that has been formed, so as to ensure the smooth flow of oil in the bottom formation and the wellbore, reduce energy loss, and ensure the normal production and production of crude oil. The present invention also provides a preparation method of the asphalt dispersing and wax removing agent for oil production.

[0005] In order to achieve the above-mentioned purpose, the first aspect of the present invention provides an asphalt dispersion dewaxing agent for oil production, the components and proportions of which are as follows in terms of mass percentage: 10% to 20% asphaltene deposition inhibitor, 10% to 20% surfactant, 1% to 5% flash point enhancer, and 55% to 79% organic hydrocarbon solvent.

[0006] Preferably, the asphaltene deposition inhibitor is selected from one or more of fatty acid amide, dodecylbenzene sulfonic acid or polyol fatty acid ester.

[0007] Preferably, the surfactant is selected from at least one of ethylene vinyl acetate copolymer, polyethylene polyamine block polyether or dodecylphenol polyoxyethylene ether.

[0008] Preferably, the flash point enhancer is selected from at least one of isopropyl myristate and ethylene glycol monomethyl ether.

[0009] Preferably, the organic hydrocarbon solvent is selected from at least one of toluene, xylene or diesel.

[0010] Another aspect of the present invention provides a method for preparing an asphalt dispersed dewaxing agent for oil production, comprising the following steps:

[0011] Step 1, adding an asphaltene deposition inhibitor to an organic hydrocarbon solvent in proportion, stirring and dissolving;

[0012] Step 2, then continue to add surfactant and stir;

[0013] Step 3: Finally, add the flash point enhancer and stir to make the system dissolve and disperse evenly to obtain an asphalt dispersed dewaxing agent for oil production.

[0014] Preferably, in step 1, an asphaltene deposition inhibitor is added to the organic hydrocarbon solvent, and the stirring and dissolving time is 20 to 30 minutes.

[0015] Preferably, in step 2, the stirring time is 10 to 20 minutes after the surfactant is added.

[0016] Preferably, in step 3, the flash point enhancer is added and the stirring time is 30 to 40 minutes.

[0017] The functions of the components of the asphalt dispersion dewaxing agent for oil production of the present invention are as follows:

[0018] The asphaltene deposition inhibitor mainly inhibits the precipitation of asphaltene in crude oil, and effectively disperses the precipitated asphaltene, slowing down its adhesion to the pores of the formation and the oil production pipeline.

[0019] The surfactant is mainly used to prevent the wax in crude oil from crystallizing.

[0020] The flash point enhancer is mainly used to adjust the flash point of the product system.

[0021] The organic hydrocarbon solvent is mainly used to dissolve the above materials to form a uniform system, and to dissolve and remove the wax formed in the oil production pipeline.

[0022] Compared with the above background technology, the present invention has the following beneficial effects:

[0023] The present invention provides an asphalt dispersing and wax removing agent, which is composed of an asphaltene deposition inhibitor, a surfactant, a flash point enhancer, and an organic hydrocarbon solvent. It has good asphaltene dispersing and wax removing effects, especially for oil wells with high waxy asphaltene content in oil field production fluid, asphaltene blockage, and severe wax deposition. It has good effects on asphaltene dispersion and wax removal in the oil production process. It can achieve an asphalt relative dispersion rate of more than 80%, a wax dissolving rate of more than 0.01 g / min, and a flash point of more than 28°C. It can be used to inhibit and disperse asphaltene deposition in various oil field production wells, prevent wax crystal precipitation, and effectively remove crystallized wax scale. Specific implementation method:

[0024] Unless otherwise specified, the experimental methods used in the following examples are conventional methods.

[0025] Unless otherwise specified, the materials and reagents used in the following examples can be obtained from commercial sources.

[0026] The invention provides an asphalt dispersing dewaxing agent for oil production, wherein the components and proportions thereof are as follows by mass percentage: 10% to 20% of asphaltene deposition inhibitor, 10% to 20% of surfactant, 1% to 5% of flash point enhancer, and 55% to 79% of organic hydrocarbon solvent.

[0027] The asphaltene deposition inhibitor is selected from one or more of fatty acid amide, dodecylbenzene sulfonic acid, and polyol fatty acid ester; the asphaltene deposition inhibitor mainly inhibits the precipitation of asphaltene in crude oil, and effectively disperses the precipitated asphaltene, slowing down its adhesion to the formation gap and oil production pipeline;

[0028] The surfactant is selected from one or more of ethylene vinyl acetate copolymer, polyethylene polyamine block polyether, and dodecylphenol polyoxyethylene ether; the surfactant mainly prevents the wax in crude oil from crystallizing;

[0029] The flash point enhancer is selected from one or more of isopropyl myristate and ethylene glycol monomethyl ether; the flash point enhancer is mainly used to adjust the flash point of the product system;

[0030] The organic hydrocarbon solvent is selected from one or more of toluene, xylene and diesel. The organic hydrocarbon solvent mainly dissolves the above materials to form a uniform system, and dissolves and removes the wax in the oil production pipeline.

[0031] The preparation process of the asphalt dispersion dewaxing agent for oil production comprises:

[0032] Add asphaltene deposition inhibitor to the organic hydrocarbon solvent in proportion, stir and dissolve for 20 to 30 minutes, then continue to add surfactant, stir for 10 to 20 minutes, and finally add flash point enhancer, stir for 30 to 40 minutes to make the system dissolved and dispersed evenly.

[0033] The present invention is further described below in conjunction with specific embodiments, but the protection scope of the present invention is not limited thereto.

[0034] Example 1

[0035] (1) Formulation: Ingredients and components are proportioned by weight:

[0036] Asphaltene deposition inhibitor is fatty acid amide and dodecylbenzene sulfonic acid (the mass ratio of fatty acid amide and dodecylbenzene sulfonic acid is 1:1) 10%;

[0037] The surfactant is ethylene vinyl acetate copolymer and polyethylene polyamine block polyether (the mass ratio of ethylene vinyl acetate copolymer and polyethylene polyamine block polyether is 1:1) 10%;

[0038] Flash point enhancer isopropyl myristate 5%;

[0039] Organic hydrocarbon solvent xylene 75%.

[0040] (2) Preparation process: Add asphaltene deposition inhibitor to organic hydrocarbon solvent in proportion, stir and dissolve for 20 minutes, then continue to add surfactant and stir for 10 minutes, and finally add flash point enhancer and stir for 30 minutes to make the system dissolved and dispersed evenly.

[0041] Example 2

[0042] (1) Formulation: Ingredients and components are proportioned by weight:

[0043] Asphaltene deposition inhibitor dodecylbenzene sulfonic acid, polyol fatty acid ester (dodecylbenzene sulfonic acid, polyol fatty acid ester mass ratio is 1:1) 10%;

[0044] Surfactant ethylene vinyl acetate copolymer, polyethylene polyamine block polyether (the mass ratio of ethylene vinyl acetate copolymer to polyethylene polyamine block polyether is 1:1) 20%;

[0045] Flash point enhancer isopropyl myristate 3%;

[0046] Organic hydrocarbon solvents: xylene and diesel (xylene: diesel mass ratio is 1:1) 67%.

[0047] (2) Preparation process: Add asphaltene deposition inhibitor to organic hydrocarbon solvent in proportion, stir and dissolve for 20 minutes, then continue to add surfactant and stir for 10 minutes, and finally add flash point enhancer and stir for 30 minutes to make the system dissolved and dispersed evenly.

[0048] Example 3

[0049] (1) Formulation: Ingredients and components are proportioned by weight:

[0050] Asphaltene deposition inhibitor fatty acid amide, dodecylbenzene sulfonic acid and polyol fatty acid ester (the mass ratio of fatty acid amide, dodecylbenzene sulfonic acid and polyol fatty acid ester is 1:1:1) 20%;

[0051] Surfactants: polyethylene polyamine block polyether, dodecylphenol polyoxyethylene ether (polyethylene polyamine block polyether, dodecylphenol polyoxyethylene ether mass ratio is 1:1) 10%;

[0052] Flash point enhancer isopropyl myristate, ethylene glycol monomethyl ether (mass ratio of isopropyl myristate to ethylene glycol monomethyl ether is 1:1) 1%;

[0053] Organic hydrocarbon solvents: toluene and xylene (the mass ratio of toluene to xylene is 1:1) 69%.

[0054] (2) Preparation process: Add asphaltene deposition inhibitor to organic hydrocarbon solvent in proportion, stir and dissolve for 20 minutes, then continue to add surfactant and stir for 10 minutes, and finally add flash point enhancer and stir for 30 minutes to make the system dissolved and dispersed evenly.

[0055] Comparative Example 1

[0056] (1) Formulation: The ingredients and composition are in the following proportions by weight:

[0057] Asphaltene deposition inhibitor (fatty acid amide, dodecylbenzene sulfonic acid, polyol fatty acid ester mass ratio of 1:1:1) 20%;

[0058] Surfactant (polyethylene polyamine block polyether and dodecylphenol polyoxyethylene ether in a mass ratio of 1:1) 10%;

[0060] Organic hydrocarbon solvent (toluene and xylene in a mass ratio of 1:1) 70%.

[0061] (2) Preparation process: Add asphaltene deposition inhibitor to the organic hydrocarbon solvent in proportion, stir and dissolve for 20 minutes, then continue to add surfactant and stir for 10 minutes to make the system dissolved and dispersed evenly.

[0062] Comparative Example 2

[0063] (1) Formulation: The ingredients and composition are in the following proportions by weight:

[0064] Surfactant polyethylene polyamine block polyether, dodecylphenol polyoxyethylene ether 10% (polyethylene polyamine block polyether: dodecylphenol polyoxyethylene ether = 1:1);

[0065] Flash point enhancer isopropyl myristate, ethylene glycol monomethyl ether (isopropyl myristate: ethylene glycol monomethyl ether = 1:1) 3%;

[0066] Organic hydrocarbon solvents: toluene and xylene (toluene:xylene=1:1) 87%.

[0067] (2) Preparation process: Add surfactant to organic hydrocarbon solvent in proportion, stir for 10 minutes, and finally add flash point enhancer and stir for 30 minutes to make the system dissolved and dispersed evenly.

[0068] The performance of the products obtained in the above examples is evaluated below:

[0069] Test standard:

[0070] The relative dispersion rate test standard of asphalt is tested according to the method in the product enterprise standard "Q / DYKP 071-2023 Asphalt dispersion wax remover polymer type LQFS for oil production";

[0071] Wax dissolution rate test standard: Test according to the method in the petroleum and natural gas industry standard "SY / T 6300-2009 Technical Conditions for Wax Removers and Wax Inhibitors for Oil Production";

[0072] Flash point test standard: Test according to the method in the national recommended standard "GB / T261 Determination of flash point - Pensky-Martin closed cup method".

[0073] The above method was used to test the products prepared in Example 1, Example 2, Example 3 and Comparative Example 1 and Comparative Example 2. The test results are shown in Table 1.

[0074] Table 1 Performance of different formulations

[0075] Examples Relative dispersion of asphalt Wax dissolving rate g / min Flash point℃ 1 82％ 0.015 34 2 85％ 0.012 31 3 90％ 0.012 29 4 90％ 0.012 25 5 20％ 0.017 30

[0076] As can be seen from Table 1, Examples 1-3 adopt the formulation system of the present invention consisting of asphaltene deposition inhibitor, surfactant, flash point enhancer, and organic hydrocarbon solvent. Compared with Comparative Examples 1-2, the relative dispersion rate of asphalt can reach greater than 80%, the wax dissolution rate is greater than 0.01 g / min, and the flash point is greater than 28°C. It can be used to inhibit and disperse asphaltene deposition in oil wells of various oil fields, prevent wax crystal precipitation, and effectively remove crystallized wax scale.

[0077] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to perform equivalent replacements on parts thereof. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention. Although the above describes the specific implementation methods of the present invention, it is not intended to limit the protection scope of the present invention. Those skilled in the art should understand that, based on the technical solution of the present invention, various modifications or deformations that can be made by those skilled in the art without creative labor are still within the protection scope of the present invention.

Claims

1. An asphalt dispersion dewaxing agent for oil production, characterized in that: The components and proportions thereof are as follows by mass percentage: asphaltene deposition inhibitor 10% to 20%; surfactant 10% to 20%; flash point enhancer 1% to 5%; organic hydrocarbon solvent 55% to 79%.

2. The asphalt dispersion dewaxing agent for oil production according to claim 1, characterized in that: The asphaltene deposition inhibitor is selected from one or more of fatty acid amide, dodecylbenzene sulfonic acid or polyol fatty acid ester.

3. The asphalt dispersion dewaxing agent for oil production according to claim 1, characterized in that: The surfactant is selected from at least one of ethylene vinyl acetate copolymer, polyethylene polyamine block polyether or dodecylphenol polyoxyethylene ether.

4. The asphalt dispersion dewaxing agent for oil production according to claim 1, characterized in that: The flash point enhancer is selected from at least one of isopropyl myristate and ethylene glycol monomethyl ether.

5. The asphalt dispersion dewaxing agent for oil production according to claim 1, characterized in that: The organic hydrocarbon solvent is selected from at least one of toluene, xylene or diesel.

6. A method for preparing an asphalt dispersed dewaxing agent for oil production according to any one of claims 1 to 5, characterized in that: The following steps are involved: Step 1, adding an asphaltene deposition inhibitor to an organic hydrocarbon solvent in proportion, stirring and dissolving, to form a first solution; Step 2, then continue to add a surfactant to the first solution and stir to form a second solution; Step 3: Finally, add the flash point enhancer to the second solution, stir to make the system dissolved and dispersed evenly, and obtain the asphalt dispersed dewaxing agent for oil production.

7. The preparation method according to claim 6, characterized in that: In the step 1, an asphaltene deposition inhibitor is added to an organic hydrocarbon solvent, and the stirring and dissolving time is 20 to 30 minutes.

8. The preparation method according to claim 6, characterized in that: In step 2, the surfactant is added to the first solution and stirred for 10 to 20 minutes.

9. The preparation method according to claim 6, characterized in that: In step 3, the flash point enhancer is finally added to the second solution and stirred for 30 to 40 minutes.