High-permeability Environmentally Friendly Paraffin Remover and Its Preparation Method

Abstract

The present invention relates to the field of oilfield chemistry, and is a high-permeability environmental protection wax remover and its preparation method. The raw materials include, by weight percentage: 50% to 70% of an organic solvent, 25% to 42% of an organic solvent penetration promoter, 2% of a penetrant, 0.5% to 1% of a co-penetrant, and the rest is a surfactant. The high-permeability environmental protection wax remover of the present invention uses birch oil as the organic solvent, and its specific gravity can be adjusted between 0.86 g / mL and 1.1 g / mL according to on-site requirements, enabling the wax remover to contact wax, gum, and asphaltene at different sections of the oil well pipe wall, quickly penetrate and dissolve to react, and can better remove wax deposits on the oil well string and gathering and transportation pipelines. It has the characteristics of good permeability, fast wax dissolution rate, safety and environmental protection. At the same time, its preparation method is simple and easy to operate, can be prepared on-site, and is convenient for popularization and application.

Description

Technical Field

[0001] The present invention relates to the technical field of oilfield chemistry, and is a high-permeability environment-friendly paraffin remover and a preparation method thereof. Background Art

[0002] During the process of crude oil production, affected by the impurity content in crude oil, the flow rate during production, temperature and pressure changes, wax, gum, and asphaltene components in crude oil precipitate, adhere to the oil casing wall, causing wax deposition in the oil well borehole. After wax deposition, the pipe string aperture shrinks, the oil flow resistance increases, which has a certain impact on crude oil production. Poor paraffin removal and prevention effects will cause the well to lie idle, making the oil well unable to produce normally, increasing the cost of subsequent paraffin removal to solve problems, and increasing the construction safety risk.

[0003] During the production process of thin oil production wells, due to the influence of the impurity content, liquid supply, and flow rate changes in the crude oil of different oil wells, as well as temperature drop and pressure release, wax deposition occurs in the oil wells. Wax deposition in oil wells brings many adverse factors to oil well production, such as increased well load, reduced pump efficiency, decreased oil well productivity, shortened service life of rod pipes, etc. At present, when using chemical agents for paraffin removal, there are mainly two types: chemical paraffin inhibitors composed of surfactants, polycyclic aromatic hydrocarbons, etc., which mainly prevent the precipitation, aggregation growth, and deposition of paraffin crystals; chemical paraffin removers are mainly composed of organic solvents, emulsifiers, surfactants, penetrants, and wax crystal modifiers. Among them, the organic solvent is mainly crude benzene or xylene, which has a low flash point, is toxic and harmful, has poor safety during use, and the specific gravity of the agent is about 0.86. For some wells with high gas production, high pressure, and high water content, when adding conventional paraffin removers, the specific gravity of the agent is small and the penetration is poor, and the ideal effect cannot be achieved. Summary of the Invention

[0004] The present invention provides a high-permeability environment-friendly paraffin remover and a preparation method thereof, which overcomes the above-mentioned deficiencies of the prior art and can effectively solve the problems of poor safety, small specific gravity, and poor penetration of existing paraffin removers.

[0005] One technical solution of the present invention is achieved by the following measures: A high-permeability environment-friendly paraffin remover, the raw materials include, by weight percentage: 50% to 70% of organic solvent, 25% to 42% of organic solvent penetration promoter, 2% of penetrant, 0.5% to 1% of co-penetrant, and the rest is surfactant.

[0006] The following is a further optimization and / or improvement of the above-mentioned invention technical solution:

[0007] The above-mentioned high-permeability environment-friendly paraffin remover is obtained by the following preparation method:

[0008] First step, mix the required amount of surfactant and organic solvent, and stir until completely dissolved to obtain the first mixed solution;

[0009] Step 2: Mix the required amounts of the penetration enhancer, penetrant, and organic solvent penetration enhancer evenly to obtain a second mixed solution.

[0010] Step 3: Add the second mixed solution to the first mixed solution and stir until completely dissolved to obtain a high-permeability environmentally friendly paraffin remover.

[0011] The above-mentioned organic solvent is birch oil.

[0012] The above-mentioned organic solvent penetration enhancer is one or both of d-limonene and turpentine.

[0013] The above-mentioned penetrant is an anionic surfactant, and the anionic surfactant is one or more of sodium dodecyl sulfate, sodium dodecylbenzenesulfonate, and lauryl alcohol phosphate.

[0014] The above-mentioned penetration enhancer is oil-soluble azone.

[0015] The above-mentioned surfactant is sodium lauryl polyoxyethylene sulfate.

[0016] The second technical solution of the present invention is achieved by the following measures: A preparation method of a high-permeability environmentally friendly paraffin remover, including the following steps:

[0017] Step 1: Mix the required amounts of the surfactant and the organic solvent evenly and stir until completely dissolved to obtain a first mixed solution.

[0018] Step 2: Mix the required amounts of the penetration enhancer, penetrant, and organic solvent penetration enhancer evenly to obtain a second mixed solution.

[0019] Step 3: Add the second mixed solution to the first mixed solution and stir until completely dissolved to obtain a high-permeability environmentally friendly paraffin remover.

[0020] The following is a further optimization or / and improvement of the second technical solution of the above invention:

[0021] The operations of the above Step 1, Step 2, and Step 3 are all carried out under the condition of a temperature of 10°C to 40°C.

[0022] The high-permeability environmentally friendly paraffin remover of the present invention adjusts the specific gravity of the paraffin remover according to different conditions of the oil well, etc., so that it can achieve a better paraffin removal effect during use, solve the problem that the paraffin removal process is limited and the medicament cannot reach the paraffin wax section of the oil well, etc., reduce the load of the oil well, assist in improving the oil well production capacity and the use of rod tubes, and it has the characteristics of good permeability, fast wax dissolution, and safety and environmental protection. Specific Embodiments

[0023] The present invention is not limited by the following embodiments, and specific implementation manners can be determined according to the technical solution of the present invention and actual situations. Various chemical reagents and chemical supplies mentioned in the present invention are well-known and commonly used chemical reagents and chemical supplies in the prior art without special instructions; percentages in the present invention are mass percentages without special instructions; normal temperature and room temperature in the present invention generally refer to the temperature from 15°C to 25°C, and are generally defined as 25°C.

[0024] The following further describes the present invention in conjunction with embodiments:

[0025] Embodiment 1: The high-permeability environment-friendly paraffin remover, the raw materials include by weight percentage: 50% to 70% of organic solvent, 25% to 42% of organic solvent penetration promoter, 2% of penetrant, 0.5% to 1% of co-penetrant, and the rest is surfactant.

[0026] Embodiment 2: The high-permeability environment-friendly paraffin remover, the raw materials include by weight percentage: 50% or 70% of organic solvent, 25% or 42% of organic solvent penetration promoter, 2% of penetrant, 0.5% or 1% of co-penetrant, and the rest is surfactant.

[0027] Embodiment 3: As an optimization of the above embodiment, the organic solvent is birch oil. The present invention uses birch oil as the organic solvent, which is also the main component of the high-permeability environment-friendly paraffin remover. Birch oil, namely methyl salicylate, can be prepared from natural plants and has higher safety and environmental protection.

[0028] Embodiment 4: As an optimization of the above embodiment, the organic solvent penetration promoter is one or two of d-limonene and turpentine.

[0029] Embodiment 5: As an optimization of the above embodiment, the penetrant is an anionic surfactant, and the anionic surfactant is one or more of sodium dodecyl sulfate, sodium dodecylbenzenesulfonate, and lauryl alcohol phosphate.

[0030] Embodiment 6: As an optimization of the above embodiment, the co-penetrant is oil-soluble azone.

[0031] Embodiment 7: As an optimization of the above embodiment, the surfactant is sodium lauryl polyoxyethylene sulfate.

[0032] Embodiment 8: The preparation method of the high-permeability environment-friendly paraffin remover includes the following steps:

[0033] The first step is to mix the required amount of surfactant and organic solvent and stir until completely dissolved to obtain a first mixed solution;

[0034] The second step is to mix the required amount of co-penetrant, penetrant, and organic solvent penetration promoter evenly to obtain a second mixed solution;

[0035] Step 3: Add the second mixture to the first mixture and stir until completely dissolved to obtain a highly permeable and environmentally friendly paraffin remover.

[0036] Example 9: As an optimization of the above example, the operations in Step 1, Step 2, and Step 3 are all carried out under the condition of a temperature of 10°C to 40°C.

[0037] Example 10: For this highly permeable and environmentally friendly paraffin remover, the raw materials include 60% methyl o-hydroxybenzoate, 32% d-limonene, 2% sodium dodecyl sulfate, 1% oil-soluble azone, and 5% sodium laureth sulfate by weight percentage.

[0038] It is obtained according to the following steps: Step 1: Mix the required amounts of sodium laureth sulfate and methyl o-hydroxybenzoate and stir until completely dissolved to obtain a first mixture; Step 2: Mix the required amounts of dodecylbenzenesulfonic acid, oil-soluble azone, and d-limonene evenly to obtain a second mixture; Step 3: Add the second mixture to the first mixture and stir until completely dissolved to obtain a highly permeable and environmentally friendly paraffin remover.

[0039] Example 11: For this highly permeable and environmentally friendly paraffin remover, the raw materials include 70% methyl o-hydroxybenzoate, 25% d-limonene, 2% dodecylbenzenesulfonic acid, 1% oil-soluble azone, and 2% sodium laureth sulfate by weight percentage.

[0040] It is obtained according to the following steps: Step 1: Mix the required amounts of sodium laureth sulfate and methyl o-hydroxybenzoate and stir until completely dissolved to obtain a first mixture; Step 2: Mix the required amounts of dodecylbenzenesulfonic acid, oil-soluble azone, and d-limonene evenly to obtain a second mixture; Step 3: Add the second mixture to the first mixture and stir until completely dissolved to obtain a highly permeable and environmentally friendly paraffin remover.

[0041] Example 12: For this highly permeable and environmentally friendly paraffin remover, the raw materials include 50% methyl o-hydroxybenzoate, 42% turpentine, 2% dodecylbenzenesulfonic acid, 1% oil-soluble azone, and 5% sodium laureth sulfate by weight percentage.

[0042] It is obtained according to the following steps: Step 1: Mix the required amounts of sodium laureth sulfate and methyl o-hydroxybenzoate and stir until completely dissolved to obtain a first mixture; Step 2: Then mix the required amounts of dodecylbenzenesulfonic acid, oil-soluble azone, and turpentine evenly to obtain a second mixture; Step 3: Add the second mixture to the first mixture and stir until completely dissolved to obtain a highly permeable and environmentally friendly paraffin remover.

[0043] Example 13: The high-permeability environmentally friendly paraffin remover, the raw materials include 70% of methyl o-hydroxybenzoate as an organic solvent, 25% of turpentine, 2% of lauryl alcohol phosphate, 1% of oil-soluble azone, and 2% of sodium lauryl polyoxyethylene sulfate by weight percentage.

[0044] It is obtained by the following steps: First step, mix the required amount of sodium lauryl polyoxyethylene sulfate and methyl o-hydroxybenzoate, and stir until completely dissolved to obtain the first mixed solution; Second step, mix the required amount of dodecylbenzenesulfonic acid, oil-soluble azone, and turpentine evenly to obtain the second mixed solution; Third step, add the second mixed solution to the first mixed solution and stir until completely dissolved to obtain the high-permeability environmentally friendly paraffin remover.

[0045] Comparative Example 1: A commercially available benzene mixture paraffin remover.

[0046] Comparative Example 2: A commercially available xylene paraffin remover.

[0047] Comparative Example 3: Different from Example 12, the organic solvent is a benzene mixture, and other components are the same.

[0048] Comparative Example 4: Different from Example 12, the penetration enhancer is not added, and other components are the same.

[0049] Perform performance tests on the high-permeability environmentally friendly paraffin removers obtained in Examples 10 to 13 of the present invention and Comparative Examples 1 to 4. At the same time, perform wax dissolution experiments on standard paraffin wax and on-site wax samples. The test indicators include the density of the agent (g / mL), flash point (°C), and wax dissolution rate (g / min). The test results are shown in Table 1. In addition, through the analysis of wax deposition in on-site oil wells, it is found that in addition to wax, the on-site wax samples contain a small amount of gum and asphaltene components. The carbon number distributions of wax samples from different oil wells in different blocks are different. Taking the wax samples of Well 1769 and Well T86245 in the Second Oil Production Plant of Xinjiang Oilfield Company as examples, the analysis of the wax samples of the two wells shows that the content ratio of solid impurities such as residual oil, oil wax, asphaltene, wax, gum, and sediment is 1.03:83.64:0.27:6.51:0.05:8.50. The carbon number distribution in the wax samples is mainly between C16 and C36. However, the wax sample of Well 1769 is hard wax, and the proportion of C20 to C36 is 75%. The melting range of the wax sample is 54°C to 56°C; the wax sample of Well T86245 is soft wax, microcrystalline wax, and the proportion of C16 to C25 is 65%. The melting range of the wax sample is 74°C to 80°C.

[0050] As can be seen from Table 1, compared with the paraffin removers of Comparative Examples 1 to 4, the high-permeability environmentally friendly paraffin removers of Examples 10 to 13 have a higher flash point, better safety performance, and a higher paraffin dissolution rate for on-site paraffin samples. Moreover, the specific gravity of the high-permeability environmentally friendly paraffin removers obtained in Examples 9 to 12 is between 1.0 g / mL and 1.1 g / mL. During construction, it can be adjusted according to different on-site requirements. When a low-specific-gravity paraffin remover is needed, the proportion of the organic solvent penetration promoter can be increased and the proportion of the organic solvent can be reduced. The lowest specific gravity of the high-permeability environmentally friendly paraffin remover can be adjusted to 0.86 g / mL. The on-site construction of the present invention is less restricted and has high safety performance. In the raw materials of the present invention, birch oil is selected as the organic solvent, which has good environmental protection. The mixing of this organic solvent and kerosene can achieve a good effect of diluting heavy oil; the penetration promoter is selected from d-limonene or turpentine, which can promote the penetration of the agent, improve the solubility of paraffin in the agent, and increase the paraffin dissolution rate; the surfactant is selected from sodium lauryl polyoxyethylene sulfate, which has the effects of emulsification and dispersion and preventing the re-crystallization and adsorption of wax crystals. The raw materials of the present invention are easily available and there is good compatibility between the components.

[0051] In summary, the present invention provides a high-permeability environmentally friendly paraffin remover, whose specific gravity can be adjusted between 0.86 g / mL and 1.1 g / mL according to on-site requirements, enabling the paraffin remover to contact wax, gum, and asphaltene at different sections of the oil well pipe wall, quickly penetrate and dissolve to react, and can better remove the wax deposition on the oil well string and gathering pipeline. It has the characteristics of good permeability, fast paraffin dissolution rate, safety and environmental protection. At the same time, its preparation method is simple and easy to operate, can be prepared on-site, and is convenient for popularization and application.

[0052] The above technical features constitute the embodiments of the present invention, which have strong adaptability and implementation effects. Non-essential technical features can be added or subtracted according to actual needs to meet the requirements of different situations.

[0053]

Claims

1. A highly permeable and environment-friendly paraffin remover, characterized in that The raw materials include, by weight percentage: 50% to 70% of organic solvent, 25% to 42% of organic solvent penetration enhancer, 2% of penetration agent, 0.5% to 1% of co-penetrant, and the balance is surfactant; wherein, the organic solvent is birch oil, the organic solvent penetration enhancer is one or both of d-limonene and turpentine, the penetration agent is one or more of sodium dodecyl sulfate, sodium dodecylbenzenesulfonate, and lauryl alcohol phosphate, the co-penetrant is oil-soluble azone, and the surfactant is sodium lauryl polyoxyethylene sulfate.

2. The high-permeability environment-friendly paraffin remover according to claim 1, wherein It is obtained by the following preparation method: In the first step, the required amount of surfactant and organic solvent are mixed evenly and stirred until completely dissolved to obtain a first mixed solution; In the second step, the required amount of co-penetrant, penetration agent, and organic solvent penetration enhancer are mixed evenly to obtain a second mixed solution; In the third step, the second mixed solution is added to the first mixed solution and stirred until completely dissolved to obtain a high-penetration environmentally friendly paraffin remover.

3. A preparation method of the high-permeability environment-friendly paraffin remover according to claim 1, characterized in that It includes the following steps: In the first step, the required amount of surfactant and organic solvent are mixed evenly and stirred until completely dissolved to obtain a first mixed solution; In the second step, the required amount of co-penetrant, penetration agent, and organic solvent penetration enhancer are mixed evenly to obtain a second mixed solution; In the third step, the second mixed solution is added to the first mixed solution and stirred until completely dissolved to obtain a high-penetration environmentally friendly paraffin remover.

4. The preparation method of the highly permeable and environment-friendly paraffin remover according to claim 3, characterized in that The operations in the first step, the second step, and the third step are all carried out under the condition of a temperature of 10°C to 40°C.

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