Preparation method of super-long carbon chain hyperbranched paraffin inhibitor and super-long carbon chain hyperbranched paraffin inhibitor

Abstract

The invention discloses a preparation method of a super-long carbon chain hyperbranched paraffin inhibitor, which is characterized by comprising the following steps: step 1, dissolving long carbon chain alpha-olefin and maleic anhydride in xylene, adding 0.1-1% of initiator benzoyl peroxide, and reacting and stirring for 25-50 minutes at 70-90 DEG C; step 2, adding p-styrene, and reacting and stirring for 20-30 minutes under the condition of 70-90 DEG C; and 3, adding organic amine with a long carbon chain, and stirring to react for 4-8 hours to obtain the hyperbranched paraffin inhibitor with the super-long carbon chain. The invention further discloses the hyperbranched paraffin inhibitor with the super-long carbon chain.

Description

Technical Field

[0001] The present invention relates to an ultra-long carbon chain hyperbranched wax inhibitor and a preparation method thereof, and belongs to the technical field of petroleum extraction. Background Art

[0002] Most crude oils are rich in wax. During the production process, as the temperature and pressure drop, the wax in the crude oil will gradually precipitate and deposit around the well wall and in the production casing, causing damage to the reservoir. Waxing is a common destructive problem in the oil and gas production process, which may occur in different locations of the crude oil production system. Waxing inside the formation will inevitably cause damage to the reservoir, block the oil and gas channels, and significantly reduce its oil phase permeability, thereby leading to reduced oil well production; the deposition of wax on the surface of the porous medium of the reservoir will change the wettability of the formation rock, thereby significantly reducing the crude oil recovery rate. Waxing at the formation perforation holes and pump inlet will increase the oil flow resistance, reduce the effective flow area, and reduce the pump efficiency; waxing on the tubing wall will reduce the oil flow channel, increase the back pressure on the formation, reduce the utilization rate of the production tubing, lead to a decrease in production, and even cause production suspension in severe cases; waxing between the tubing and the sucker rod will increase the load on the pump, increase the difficulty of equipment operation and maintenance, and even cause production failures such as wax jam in the pump. Wax deposition on oil pipelines will increase pump pressure, power consumption, and reduce the transportation capacity of the oil pipeline. At the same time, as wax continues to accumulate, the wax layer will continue to thicken, and the transportation diameter of the oil pipeline will continue to shrink. In order to maintain production, it is often necessary to increase the pressure at the end of the oil pipeline. Once it exceeds the maximum value that the pipeline can withstand, it will cause the pipeline to rupture, which will not only cause damage to the oil pipeline, but also cause crude oil leakage and infiltration into the formation, which will have a great impact on environmental safety.

[0003] Using chemical agents to prevent wax in oil wells is a widely used wax prevention technology in oil fields. Generally, chemical wax prevention is based on two mechanisms. First, one or more agents can form a polar film on the metal surface to affect the wettability of the metal surface, thereby reducing wax deposition; second, one or more agents are added to change the structure of wax crystals or make wax crystals dispersed, thereby suspending in crude oil. Wax prevention agents are developed based on the above principles.

[0004] Common wax inhibitors include aromatic hydrocarbon solvents that can dissolve paraffin; polymer wax crystal modifiers that can inhibit or change the growth of wax crystals; and wax crystal dispersants that can inhibit particle aggregation and keep wax crystals in a dispersed state.

[0005] The mechanism of action of polymer wax crystal modifier is that the modifier molecules have side chains of a certain length, and have structures and polar groups similar to those of paraffin molecules in the main chain or side chain of the molecule. At lower temperatures, the paraffin-like structures in their molecules form eutectics with paraffin molecules. Since there are polar groups in their molecules, the formed crystal nuclei are distorted and deformed, which is not conducive to the continued growth of wax crystals.

[0006] Existing methods disclose some methods for preparing wax inhibitors, which are usually prepared by copolymerizing long carbon chain α-olefins and maleic anhydride. However, the effects of wax inhibitors prepared by the existing methods are still difficult to meet the actual wax inhibitor needs. Summary of the invention

[0007] The purpose of this application is to provide a method for preparing an ultra-long carbon chain hyperbranched wax inhibitor, the steps of which are as follows:

[0008] Step 1: Dissolve long carbon chain α-olefin and maleic anhydride in xylene, add 0.1-1% initiator benzoyl peroxide, and react and stir at 70-90° C. for 25-50 minutes;

[0009] Step 2: Add p-styrene and stir at 70-90°C for 20-30 minutes;

[0010] Step 3: adding an organic amine with a long carbon chain, and stirring and reacting for 4 to 8 hours to obtain an ultra-long carbon chain hyperbranched anti-wax agent.

[0011] In a preferred embodiment, the long carbon chain α-olefin is at least one of octadecene, eicosene, docosene, tetracosene, octacosene and triacontene.

[0012] In a preferred embodiment, the organic amine is at least one of dodecylamine, tetradecylamine, hexadecylamine, octadecylamine and eicosylamine.

[0013] In a preferred embodiment, the ratio of the long carbon chain α-olefin to maleic anhydride is 1:1-5.

[0014] In a preferred embodiment, the ratio of styrene to maleic anhydride is 1:1-5.

[0015] In a preferred embodiment, the reaction stirring time in step 1 is 30 minutes.

[0016] In a preferred embodiment, the reaction stirring time in step 2 is 20 minutes.

[0017] In a preferred embodiment, the reaction stirring time in step three is 5 hours.

[0018] The application also discloses an ultra-long carbon chain hyperbranched wax inhibitor, which is prepared according to the method.

[0019] The invention can destroy the original structural arrangement of wax crystals, so that paraffin will not continue to grow to form wax deposits, and can produce eutectic effect with paraffin molecules to prevent wax crystals from forming a three-dimensional network structure, so that the paraffin crystals dispersed in crude oil are prevented from bonding and growing, thereby achieving the anti-wax effect, and having good anti-wax performance;

[0020] The hyperbranched wax inhibitor of the present invention has a small dosage and good wax inhibitor effect. Compared with conventional wax inhibitors, it can effectively inhibit the precipitation of high carbon number paraffin in crude oil, greatly reduce the blockage of crude oil gathering and transportation pipelines by wax deposition, and has low construction cost and simple on-site construction process.

[0021] The ultra-long carbon chain hyperbranched wax inhibitor provided by the present invention has the functions of mainly preventing wax and supplementing with pour point reduction. The product is neutral, non-corrosive, stable in storage, easy to use and simple in preparation.

[0022] The raw materials of the invention are easy to obtain, have good compatibility with each other, have the characteristics of wide applicable temperature and significant anti-wax effect. DETAILED DESCRIPTION

[0023] The present invention application is described in detail below.

[0024] Example 1

[0025] Octadecene, maleic anhydride and styrene are dissolved in xylene, wherein the molar ratio of octadecene, maleic anhydride and styrene is 1:1:1. In a nitrogen environment, 0.1% of benzoyl peroxide as an initiator is added. After reacting at 70°C for 30 minutes, dodecylamine is added for modification, wherein the ratio of the three monomers to dodecylamine is 1:0. After reacting for 4 hours, an ultra-long carbon chain hyperbranched wax inhibitor is obtained.

[0026] Example 2

[0027] Eicosene, maleic anhydride and styrene are dissolved in xylene, wherein the molar ratio of eicosene, maleic anhydride and styrene is 1:2:1. In a nitrogen environment, 0.2% of benzoyl peroxide as an initiator is added. After reacting at 70°C for 30 minutes, tetradecylamine is added for modification, wherein the ratio of the three monomers to tetradecylamine is 1:0.5. After reacting for 5 hours, an ultra-long carbon chain hyperbranched wax inhibitor is obtained.

[0028] Example 3

[0029] Dissolve docosene, maleic anhydride and styrene in xylene, wherein the molar ratio of docosene, maleic anhydride and styrene is 1:2:2. In a nitrogen environment, add 0.3% of initiator benzoyl peroxide, react at 80°C for 30 minutes, then add hexadecylamine for modification, wherein the ratio of the three monomers to hexadecylamine is 0.5:1, and react for 6 hours to obtain an ultra-long carbon chain hyperbranched wax inhibitor.

[0030] Example 4

[0031] Dissolve tetracosene, maleic anhydride and styrene in xylene, wherein the molar ratio of tetracosene, maleic anhydride and styrene is 1:1:2. Add 0.4% initiator benzoyl peroxide in a nitrogen environment, react at 85°C for 30 minutes, then add octadecylamine for modification, wherein the ratio of the three monomers to octadecylamine is 1:2, and react for 7 hours to obtain an ultra-long carbon chain hyperbranched wax inhibitor.

[0032] Example 5

[0033] Octadecosene, maleic anhydride and styrene are dissolved in xylene, wherein the molar ratio of octacosene, maleic anhydride and styrene is 1:3:1. In a nitrogen environment, 0.5% of initiator benzoyl peroxide is added, and the reaction is carried out at 90°C for 30 minutes. Then, eicosamine is added for modification, wherein the ratio of the three monomers to eicosamine is 2:1. The reaction is carried out for 8 hours to obtain an ultra-long carbon chain hyperbranched wax inhibitor.

[0034] The evaluation of paraffin inhibitors is carried out in accordance with the standard SYT 6300-2009 "Technical Requirements for Paraffin Removal and Inhibition Agents for Oil Production".

[0035] Table 1 Wax resistance rate

[0036]

[0037] Experiments show that the ultra-long carbon chain hyperbranched paraffin inhibitor of the present invention has a good paraffin inhibitor effect on high wax content crude oil. At an addition amount of 250 ppm, the maximum paraffin inhibitor rate can reach 88%.

[0038] Example 6

[0039] Octadecene and maleic anhydride are dissolved in xylene, and in a nitrogen environment, 0.1% of benzoyl peroxide as an initiator is added, and the reaction is carried out at 70° C. for 30 minutes. Then, styrene is added and the reaction is carried out at 70° C. for 20 minutes, wherein the molar ratio of octadecene, maleic anhydride and styrene is 1:1:1 to obtain an ultra-long carbon chain hyperbranched anti-wax agent.

[0040] Example 7

[0041] Take the molar ratio of eicosene, maleic anhydride and styrene as 1:2:1, dissolve eicosene and maleic anhydride in xylene, add 0.2% of initiator benzoyl peroxide in a nitrogen environment, react at 70°C for 30 minutes, add styrene, react at 70°C for 20 minutes, then add tetradecamine for modification, wherein the ratio of the three monomers to tetradecamine is 1:0.5, react for 5 hours, and obtain an ultra-long carbon chain hyperbranched wax inhibitor.

[0042] Example 8

[0043] Take docosene, maleic anhydride and styrene in a molar ratio of 1:2:2, dissolve docosene and maleic anhydride in xylene, add 0.3% of initiator benzoyl peroxide in a nitrogen environment, react at 80°C for 30 minutes, then add styrene, react at 80°C for 30 minutes, then add hexadecylamine for modification, wherein the ratio of the three monomers to hexadecylamine is 0.5:1, react for 6 hours, and thus an ultra-long carbon chain hyperbranched wax inhibitor is obtained.

[0044] Example 9

[0045] Take tetracosene, maleic anhydride and styrene in a molar ratio of 1:1:2, dissolve tetracosene and maleic anhydride in xylene, add 0.4% initiator benzoyl peroxide in a nitrogen environment, react at 85°C for 30 minutes, then add styrene, react at 85°C for 20 minutes, then add octadecylamine for modification, wherein the ratio of the three monomers to octadecylamine is 1:2, react for 7 hours, and thus obtain an ultra-long carbon chain hyperbranched wax inhibitor.

[0046] Example 10

[0047] Take octacosene, maleic anhydride and styrene in a molar ratio of 1:3:1, dissolve octacosene and maleic anhydride in xylene, add 0.5% of initiator benzoyl peroxide in a nitrogen environment, react at 90°C for 30 minutes, then add styrene, react at 90°C for 20 minutes, then add eicosamine for modification, wherein the ratio of the three monomers to eicosamine is 2:1, react for 8 hours, and thus obtain an ultra-long carbon chain hyperbranched wax inhibitor.

[0048]

[0049] The test shows that, compared with Examples 1-5, in Examples 6-10, the wax resistance is greatly improved when the monomers are added together instead of separately. It is speculated that this may be caused by the change in the distribution of the styrene monomer on the molecular chain.

Claims

1. A method for preparing an ultra-long carbon chain hyperbranched wax inhibitor, characterized in that: The steps are as follows: Step 1: Dissolve long carbon chain α-olefin and maleic anhydride in xylene, add 0.1-1% initiator benzoyl peroxide, and react and stir at 70-90° C. for 25-50 minutes; Step 2: Add p-styrene and stir at 70-90°C for 20-30 minutes; Step 3: Add an organic amine with a long carbon chain, and then stir and react for 4 to 8 hours to obtain an ultra-long carbon chain hyperbranched anti-wax agent.

2. The ultra-long carbon chain hyperbranched wax inhibitor according to claim 1, characterized in that The long carbon chain α-olefin is at least one of octadecene, eicosene, docosene, tetracosene, octacosene and triacontene.

3. The ultra-long carbon chain hyperbranched wax inhibitor according to claim 1, characterized in that The organic amine is at least one of dodecylamine, tetradecylamine, hexadecylamine, octadecylamine and eicosylamine.

4. The ultra-long carbon chain hyperbranched wax inhibitor according to claim 3, characterized in that The ratio of the long carbon chain alpha-olefin to maleic anhydride is 1:1-5.

5. The ultra-long carbon chain hyperbranched wax inhibitor according to claim 4, characterized in that The ratio of styrene to maleic anhydride is 1:1-5.

6. The ultra-long carbon chain hyperbranched wax inhibitor according to claim 1, characterized in that The reaction stirring time in the step 1 is 30 min.

7. The ultra-long carbon chain hyperbranched wax inhibitor according to claim 6, characterized in that The reaction stirring time in the step 2 is 20 min.

8. The ultra-long carbon chain hyperbranched wax inhibitor according to claim 7, characterized in that The reaction stirring time in step 3 is 5 hours.

9. An ultra-long carbon chain hyperbranched wax inhibitor, characterized in that: Prepared according to the method according to any one of claims 1 to 8.

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