Oil-based wax remover and preparation method

Abstract

The invention relates to the technical field of oil-based wax removal and prevention, and discloses an oil-based wax removal and prevention agent and a preparation method. Xylene has rapid dissolution ability and a large saturated wax dissolving capacity, and can achieve "like dissolves like" for wax. The molecular structure of the polyacrylate pour point depressant and viscosity reducer simultaneously comprises two long-chain lipophilic groups and a sodium sulfonate hydrophilic group. The structure of the lipophilic group is similar to that of paraffin wax, and can form a eutectic with the paraffin wax, thereby inhibiting the continued growth of wax crystals. The hydrophilic group extends outward, hindering the subsequent precipitated paraffin wax from combining with the agent to form a three-dimensional network structure, preventing the wax crystals from adhering to each other, and further exerting the wax prevention and removal effect. The polyacrylate pour point depressant and viscosity reducer has good solubility in crude oil, and its alkyl side chain can fully react with the paraffin wax in the crude oil, thereby changing the structural morphology of the wax crystals, increasing the flow space of the liquid oil, and reducing the flow resistance of the crude oil, thereby exerting the pour point and viscosity reduction effect on the crude oil.

Description

Technical Field

[0001] The invention relates to the technical field of oil-based wax removal and prevention, in particular to an oil-based wax removal and prevention agent and a preparation method thereof. Background Art

[0002] Waxing of crude oil is a common phenomenon. During the oil production process, wax in crude oil continuously precipitates and grows in the form of crystals and is deposited in downhole equipment, seriously affecting the normal production of oil wells. It may even cause serious problems such as stuck tubing and blocked surface pipelines, causing many inconveniences to crude oil production and construction operations, and seriously reducing the production of oil and natural gas. Severe wax deposition in the wellbore requires frequent on-site wax cleaning operations, high operating costs, and greatly increases the cost of crude oil production. Therefore, there is an urgent need to develop a wax remover and wax preventer that has both wax removal and wax preventive effects to effectively solve the problem of wax deposition in the wellbore.

[0003] In order to inhibit and remove the deposited paraffin, people have used various methods to deal with the deposited wax. The wax removal and prevention technologies currently developed and used at home and abroad mainly include mechanical wax removal technology, heating wax removal and prevention technology, lined oil pipe wax prevention technology, chemical wax removal and prevention technology, etc. Among them, the chemical wax removal and prevention method can change the total amount of wax in crude oil and inject it from the annular space of the oil casing without affecting the normal production of the oil well and other operations; currently, certain agents are used in the chemical wax removal and prevention technology to produce the effect of reducing viscosity and removing blockage; chemical wax removal and prevention agents mainly include oil-based wax removal and prevention agents, water-based wax removal and prevention agents and emulsion wax removal and prevention agents, among which emulsion wax removal agents must have stable preparation and storage conditions. The wax is not easy to remove and the wax is not easy to remove. The wax is not easy to remove and the wax is not easy to remove. The wax is not easy to remove and the wax is not easy to remove. The wax is not easy to remove and the wax is not easy to remove. The wax is not easy to remove and the wax is not easy to remove. The wax is not easy to remove and the wax is not easy to remove.

[0004] The present invention synthesizes a polyacrylate pour point and viscosity reducer containing both hydrophilic groups and lipophilic groups, wherein the lipophilic groups form a eutectic with paraffin, and the paraffin precipitated after the hydrophilic groups are blocked is combined with the paraffin to form a three-dimensional network structure. In addition, by compounding the oil-based wax remover and preventative agent solvent and auxiliary agents, an oil-based wax remover and preventative agent with a fast wax dissolving rate is obtained, which does not contain harmful substances such as organic chlorine and carbon disulfide, has high wax prevention efficiency and is environmentally friendly. Summary of the Invention

[0005] The purpose of the present invention is to overcome the shortcomings of the existing technology and provide an oil-based paraffin removal and prevention agent and a preparation method, which solves the problem of poor paraffin removal and prevention effect of the existing technology and further plays a role in reducing the pour point and viscosity of crude oil.

[0006] To achieve the above object, the technical solution adopted by the present invention is:

[0007] An oil-based wax remover and inhibitor comprises the following components in parts by weight: 70-99 parts of xylene, 10-35 parts of straight-run gasoline, 2-10 parts of mutual solvents, 0.5-5 parts of surfactants, 1-15 parts of polyacrylate pour point and viscosity reducers, and 0.1-0.5 parts of fast penetrants.

[0008] The preparation method of the polyacrylate pour point depressant and viscosity reducer comprises the following steps:

[0009] (1) Add sodium 3-chloro-2-hydroxypropylsulfonate, ethanol, and deionized water to a reaction flask equipped with a reflux condenser, stir evenly, then add allylamine hydrochloride and sodium carbonate, stir and react. After the reaction is complete, cool to room temperature, filter, recrystallize from ethanol, and dry to obtain sodium 3-(allylamino)-2-hydroxypropane-1-sulfonate. The preparation process is as follows:

[0010]

[0011] (2) Add sodium 3-(allylamino)-2-hydroxypropane-1-sulfonate and toluene to a reaction flask equipped with a reflux condenser and a water separator. After stirring evenly, add triethylamine and long-chain alkyl acyl chloride. Heat to 105-120°C and react for 8-14 hours. When no water is produced in the water separator, cool, extract and separate the liquid. Concentrate the organic phase to obtain sodium olefin sulfonate acrylate monomer. The preparation process is as follows:

[0012]

[0013] (3) Add sodium olefin sulfonate acrylate monomer and toluene to a reaction flask equipped with a reflux condenser, stir evenly, then add N,N'-methylenebisacrylamide and initiator ammonium persulfate, stir to react, and after the reaction is completed, cool to room temperature and concentrate to obtain a polyacrylate pour point and viscosity reducer.

[0014] Furthermore, in step (1), the ratio of sodium 3-chloro-2-hydroxypropylsulfonate, allylamine hydrochloride, and sodium carbonate is 1 mol: (1.05-1.2) mol: (2.5-4) mol.

[0015] Furthermore, in step (1), the reaction temperature is 75-90° C., and the reaction time is 8-16 h.

[0016] Furthermore, in step (2), the long-chain alkyl acyl chloride is any one of palmitoyl chloride, heptadecanoyl chloride, stearoyl chloride, and nonadecanoyl chloride.

[0017] Furthermore, in step (2), the ratio of sodium 3-(allylamino)-2-hydroxypropane-1-sulfonate, triethylamine, and long-chain alkyl acyl chloride is 1 mol: (2.1-2.2) mol: (2.2-2.5) mol.

[0018] Furthermore, in step (3), the ratio of sodium olefin sulfonate acrylate monomer, N,N'-methylenebisacrylamide, and ammonium persulfate is 1 mol: (0.03-0.06) mol: (0.02-0.05) mol.

[0019] Furthermore, in step (3), the reaction temperature is 60-80° C., and the reaction time is 4-10 h.

[0020] Furthermore, the mutual solvent is ethylene glycol monobutyl ether or diethylene glycol ethyl ether.

[0021] Furthermore, the surfactant is OP-10; and the rapid penetrant is polyoxyethylene octanol ether.

[0022] Furthermore, xylene, straight-run gasoline, mutual solvent and surfactant are added to the reaction bottle, stirred at a temperature of 20-35°C and a rotation speed of 600-1000 r / min for 10-30 minutes, and after uniform dispersion, a fast penetrant is added, and stirring is continued for 5-20 minutes. Then, a polyacrylate pour point and viscosity reducer is added, and stirring is uniform to obtain an oil-based paraffin remover and inhibitor.

[0023] By adopting the above technical solution, the beneficial effects of the present invention are:

[0024] The invention first reacts sodium 3-chloro-2-hydroxypropyl sulfonate and allylamine hydrochloride under the action of sodium carbonate to obtain sodium 3-(allylamino)-2-hydroxypropane-1-sulfonate; then, the hydroxyl group of sodium 3-(allylamino)-2-hydroxypropane-1-sulfonate and long-chain alkyl chloride are subjected to an esterification reaction under the action of triethylamine to obtain sodium olefin sulfonate acrylate monomer; then, under the action of initiator ammonium persulfate and cross-linking agent N,N'-methylenebisacrylamide, a polymerization reaction is carried out to obtain a polyacrylate pour point and viscosity reducer; finally, the polyacrylate is compounded with xylene, straight-run gasoline, a mutual solvent and a penetrant to obtain an oil-based paraffin remover and inhibitor.

[0025] Polyacrylate pour point and viscosity reducer is a comb-like polymer with two long-chain lipophilic groups and a sodium sulfonate hydrophilic group in its molecular structure. The lipophilic groups are similar in structure to paraffin wax and can form a eutectic with paraffin wax, preventing the wax crystals from growing further. The hydrophilic groups extend outward, hindering the subsequent precipitated paraffin wax from combining with it to form a three-dimensional network structure. This can prevent the wax crystals from adhering to each other, change the spatial network structure and morphology of the wax crystals in the oil phase, reduce wax crystal adsorption, and further play a wax prevention role. At the same time, the polyacrylate pour point and viscosity reducer has a long molecular chain that is distributed throughout the oil phase, which can disperse the formed crystal nuclei and prevent the wax crystals from growing further. In addition, the polyacrylate pour point and viscosity reducer has structural units similar to wax crystals and has good solubility in crude oil. The alkyl side chains on the molecular chain can fully interact with the paraffin wax in the crude oil, making the molecular chain more extended, forming an adsorption eutectic with the wax crystals, thereby changing the structural morphology of the wax crystals, increasing the flow space of the liquid oil, and reducing the flow resistance of the crude oil, thereby achieving a pour point and viscosity reduction effect, facilitating smooth mining operations.

[0026] The 2-octanol polyoxyethylene ether penetrant added to the wax remover and wax preventer has a very strong penetrating effect. After being added, the wax remover and wax preventer can fully contact and react with the wax crystals in the crude oil and wax sample, dissolve and disperse the deposited wax, and at the same time, it can be adsorbed on the surface of the wax crystals during the precipitation and growth stage of the wax crystals to prevent the wax crystals from continuing to grow and deposit, playing a certain anti-wax effect; according to the "like dissolves like" principle, wax crystals can be dissolved in the polyacrylate pour point and viscosity reducer, xylene has a fast dissolving ability and a large saturated wax dissolving capacity, which can achieve "like dissolves like" for wax, and the mutual solvent can make the various components of the wax remover and wax preventer well dissolved in the wax solvent, so that it can better contact and react with the wax in the crude oil, thereby accelerating the wax dissolution rate and improving the wax removal effect of the wax remover; at the same time, the surfactant has a strong emulsifying ability, which can achieve emulsification reversal viscosity reduction and reduce the viscosity of crude oil. DETAILED DESCRIPTION

[0027] In order to more clearly understand the above-mentioned objects, features and advantages of the present invention, the present invention is further described in detail below in conjunction with specific embodiments. It should be noted that, in the absence of conflict, the embodiments of the present application and the features therein can be combined with each other.

[0028] Sodium 3-chloro-2-hydroxypropanesulfonate, CAS number is 126-83-0.

[0029] Palmitoyl chloride, CAS number 112-67-4.

[0030] Heptadecanoyl chloride, CAS number is 40480-10-2.

[0031] Stearyl chloride, CAS number is 112-76-5.

[0032] Nonadecanoyl chloride, CAS number is 59410-47-8.

[0033] Straight-run gasoline, No. 120 solvent gasoline.

[0034] Example 1

[0035] (1) Add 20 mmol of sodium 3-chloro-2-hydroxypropylsulfonate, 150 mL of ethanol, and 15 mL of deionized water to a reaction flask equipped with a reflux condenser. After stirring evenly, add 22 mmol of allylamine hydrochloride and 60 mmol of sodium carbonate. React at 85 °C for 12 h, cool to room temperature, filter, recrystallize from ethanol, and dry to obtain sodium 3-(allylamino)-2-hydroxypropane-1-sulfonate.

[0036] (2) Add 15 mmol of sodium 3-(allylamino)-2-hydroxypropane-1-sulfonate and 180 mL of toluene to a reaction flask equipped with a reflux condenser and a water separator. After stirring evenly, add 32.4 mmol of triethylamine and 35.4 mmol of palmitoyl chloride. Heat to 115°C and react for 12 hours. When no water is produced in the water separator, cool, extract and separate the liquid. Concentrate the organic phase to obtain sodium olefin sulfonate acrylate monomer.

[0037] (3) Add 5 mmol of sodium olefin sulfonate acrylate monomer and 110 mL of toluene to a reaction flask equipped with a reflux condenser, stir evenly, then add 0.25 mmol of N,N'-methylenebisacrylamide and 0.2 mmol of initiator ammonium persulfate, react at 75 °C for 7 h, cool to room temperature, and concentrate to obtain a polyacrylate pour point and viscosity reducer.

[0038] (4) Add 99g of xylene, 10g of straight-run gasoline, 2g of ethylene glycol monobutyl ether and 0.5g of OP-10 into the reaction bottle, stir at a temperature of 25℃ and a speed of 800r / min for 25min, and after uniform dispersion, add 0.2g of octanol polyoxyethylene ether JFC-2 penetrant, continue stirring for 10min, and then add 1g of polyacrylate pour point and viscosity reducer, stir evenly, and obtain an oil-based paraffin remover and preventer.

[0039] Example 2

[0040] (1) To a reaction flask equipped with a reflux condenser, add 80 mmol of sodium 3-chloro-2-hydroxypropylsulfonate, 400 mL of ethanol, and 40 mL of deionized water. After stirring evenly, add 84 mmol of allylamine hydrochloride and 200 mmol of sodium carbonate. React at 90 °C for 8 h, cool to room temperature, filter, recrystallize from ethanol, and dry to obtain sodium 3-(allylamino)-2-hydroxypropane-1-sulfonate.

[0041] (2) Add 50 mmol of sodium 3-(allylamino)-2-hydroxypropane-1-sulfonate and 500 mL of toluene to a reaction flask equipped with a reflux condenser and a water separator. After stirring evenly, add 105 mmol of triethylamine and 110 mmol of heptadecanoyl chloride. Heat to 120°C and react for 8 hours. When no water is produced in the water separator, cool, extract and separate the liquid. Concentrate the organic phase to obtain sodium olefin sulfonate acrylate monomer.

[0042] (3) Add 25 mmol of sodium olefin sulfonate acrylate monomer and 500 mL of toluene to a reaction flask equipped with a reflux condenser, stir evenly, then add 0.75 mmol of N,N'-methylenebisacrylamide and 0.5 mmol of initiator ammonium persulfate, react at 80 °C for 4 h, cool to room temperature, and concentrate to obtain a polyacrylate pour point and viscosity reducer.

[0043] (4) Add 95g of xylene, 15g of straight-run gasoline, 4g of diethylene glycol ethyl ether and 1.5g of OP-10 into a reaction flask, stir at a temperature of 35°C and a speed of 1000r / min for 10min, and after uniform dispersion, add 0.2g of octanol polyoxyethylene ether JFC-2 penetrant, continue stirring for 5min, then add 5g of polyacrylate pour point and viscosity reducer, stir evenly, and obtain an oil-based paraffin remover and inhibitor.

[0044] Example 3

[0045] (1) To a reaction flask equipped with a reflux condenser, add 15 mmol of sodium 3-chloro-2-hydroxypropylsulfonate, 150 mL of ethanol, and 15 mL of deionized water. After stirring evenly, add 18 mmol of allylamine hydrochloride and 60 mmol of sodium carbonate. React at 75 °C for 16 h, cool to room temperature, filter, recrystallize from ethanol, and dry to obtain sodium 3-(allylamino)-2-hydroxypropane-1-sulfonate.

[0046] (2) Add 30 mmol of sodium 3-(allylamino)-2-hydroxypropane-1-sulfonate and 450 mL of toluene to a reaction flask equipped with a reflux condenser and a water separator. After stirring evenly, add 66 mmol of triethylamine and 75 mmol of stearyl chloride. Heat to 105 °C and react for 14 h. When no water is produced in the water separator, cool, extract and separate the liquid. Concentrate the organic phase to obtain sodium olefin sulfonate acrylate monomer.

[0047] (3) Add 8 mmol of sodium olefin sulfonate acrylate monomer and 200 mL of toluene to a reaction flask equipped with a reflux condenser, stir evenly, then add 0.48 mmol of N,N'-methylenebisacrylamide and 0.4 mmol of initiator ammonium persulfate, react at 60 °C for 10 h, cool to room temperature, and concentrate to obtain a polyacrylate pour point and viscosity reducer.

[0048] (4) Add 85g of xylene, 25g of straight-run gasoline, 6g of diethylene glycol ethyl ether and 3g of OP-10 into a reaction bottle, stir at a temperature of 20°C and a speed of 600r / min for 30min, and after uniform dispersion, add 0.3g of octanol polyoxyethylene ether JFC-2 penetrant, continue stirring for 20min, then add 8g of polyacrylate pour point and viscosity reducer, stir evenly, and obtain an oil-based paraffin remover and preventer.

[0049] Example 4

[0050] (1) To a reaction flask equipped with a reflux condenser, 14 mmol of sodium 3-chloro-2-hydroxypropylsulfonate, 112 mL of ethanol, and 10 mL of deionized water were added. After stirring evenly, 16.1 mmol of allylamine hydrochloride and 49 mmol of sodium carbonate were added. The mixture was reacted at 80 °C for 15 h, cooled to room temperature, filtered, recrystallized from ethanol, and dried to obtain sodium 3-(allylamino)-2-hydroxypropane-1-sulfonate.

[0051] (2) Add 10 mmol of sodium 3-(allylamino)-2-hydroxypropane-1-sulfonate and 130 mL of toluene to a reaction flask equipped with a reflux condenser and a water separator, stir evenly, add 21.2 mmol of triethylamine and 24 mmol of 18-acetyl chloride, heat to 110°C and react for 12 hours. When no water is produced in the water separator, cool, extract and separate the liquid, and concentrate the organic phase to obtain sodium olefin sulfonate acrylate monomer.

[0052] (3) Add 30 mmol of sodium olefin sulfonate acrylate monomer and 660 mL of toluene to a reaction flask equipped with a reflux condenser, stir evenly, then add 1.56 mmol of N,N'-methylenebisacrylamide and 1.35 mmol of initiator ammonium persulfate, react at 75 °C for 10 h, cool to room temperature, and concentrate to obtain a polyacrylate pour point and viscosity reducer.

[0053] (4) Add 75g of xylene, 30g of straight-run gasoline, 8g of ethylene glycol monobutyl ether and 4g of OP-10 into a reaction bottle, stir at a temperature of 25°C and a speed of 850r / min for 15min, and after uniform dispersion, add 0.4g of octanol polyoxyethylene ether JFC-2 penetrant, continue stirring for 10min, then add 11g of polyacrylate pour point and viscosity reducer, stir evenly, and obtain an oil-based paraffin remover and preventer.

[0054] Example 5

[0055] (1) To a reaction flask equipped with a reflux condenser, add 5 mmol of sodium 3-chloro-2-hydroxypropylsulfonate, 45 mL of ethanol, and 5 mL of deionized water. After stirring evenly, add 5.9 mmol of allylamine hydrochloride and 19 mmol of sodium carbonate. React at 85 °C for 12 h, cool to room temperature, filter, recrystallize from ethanol, and dry to obtain sodium 3-(allylamino)-2-hydroxypropane-1-sulfonate.

[0056] (2) Add 3 mmol of sodium 3-(allylamino)-2-hydroxypropane-1-sulfonate and 39 mL of toluene to a reaction flask equipped with a reflux condenser and a water separator. After stirring evenly, add 6.6 mmol of triethylamine and 7.2 mmol of stearyl chloride. Heat to 110°C and react for 14 h. When no water is produced in the water separator, cool, extract and separate the liquid. Concentrate the organic phase to obtain sodium olefin sulfonate acrylate monomer.

[0057] (3) Add 15 mmol of sodium olefin sulfonate acrylate monomer and 300 mL of toluene to a reaction flask equipped with a reflux condenser, stir evenly, then add 0.73 mmol of N,N'-methylenebisacrylamide and 0.75 mmol of initiator ammonium persulfate, react at 80 °C for 7 h, cool to room temperature, and concentrate to obtain a polyacrylate pour point and viscosity reducer.

[0058] (4) Add 70g of xylene, 35g of straight-run gasoline, 10g of ethylene glycol monobutyl ether and 5g of OP-10 into the reaction bottle, stir at a temperature of 35℃ and a speed of 900r / min for 25min, and after uniform dispersion, add 0.5g of octanol polyoxyethylene ether JFC-2 penetrant, continue stirring for 15min, then add 15g of polyacrylate pour point and viscosity reducer, stir evenly, and obtain an oil-based paraffin remover and preventer.

[0059] Comparative Example 1

[0060] Add 99g of xylene, 10g of straight-run gasoline, 2g of ethylene glycol monobutyl ether and 0.5g of OP-10 into a reaction bottle, stir at a temperature of 25°C and a speed of 800r / min for 25min, and after uniform dispersion, add 0.2g of octanol polyoxyethylene ether JFC-2 penetrant, continue stirring for 10min, and after uniform stirring, obtain an oil-based paraffin remover and inhibitor.

[0061] Comparative Example 2

[0062] (1) To a reaction flask equipped with a reflux condenser, 5 mmol of sodium 3-(allylamino)-2-hydroxypropane-1-sulfonate (prepared in Example 1) and 110 mL of toluene were added and stirred evenly. Then, 0.25 mmol of N,N'-methylenebisacrylamide and 0.2 mmol of initiator ammonium persulfate were added. The mixture was reacted at 75°C for 7 h, cooled to room temperature, and concentrated to obtain a polymer modifier.

[0063] (2) Add 99g of xylene, 10g of straight-run gasoline, 2g of ethylene glycol monobutyl ether and 0.5g of OP-10 into a reaction bottle, stir at a temperature of 25°C and a speed of 800r / min for 25min, and after uniform dispersion, add 0.2g of octanol polyoxyethylene ether JFC-2 penetrant, continue stirring for 10min, then add 1g of polymer modifier and stir evenly to obtain an oil-based paraffin remover and inhibitor.

[0064] Wax prevention rate test: referring to the standard SY / T6300-2009 "Technical conditions for wax cleaners and paraffin inhibitors for oil production", the wax prevention rate of wax cleaners and paraffin inhibitors at different temperatures was tested using the circulating wax tube method. The wax prevention rate f is calculated as f=(m1-m0) / m1, where f is the wax prevention rate (%), m1 is the wax content (g) of the oil sample without oil-based wax cleaner and paraffin inhibitor, and m0 is the wax content (g) of the oil sample with oil-based wax cleaner and paraffin inhibitor.

[0065] Wax dissolution rate test: Wax dissolution rate tests were conducted in accordance with the standard SY / T6300-2009, "Technical Requirements for Wax Removers and Wax Inhibitors for Oil Production." 15 mL of each of the oil-based wax removers and wax inhibitors prepared in the examples and comparative examples was added to the wax dissolution test apparatus. The water bath temperature was set at 30°C. After the solution reached a constant temperature, a wax ball of mass m was placed into the wax remover and wax inhibitor solution. The time t required for the wax ball to completely dissolve at room temperature was recorded. The wax dissolution rate, V, was calculated using the formula: V = m / t, where V is the wax dissolution rate (g / min), m is the mass of the wax ball (g), and t is the time required for the wax ball to completely dissolve (min).

[0066] Table 1 Wax resistance and wax dissolving performance test

[0067]

[0068] As can be seen from the test results in the above table, as the content of the polyacrylate pour point depressant and viscosity reducer in the oil-based paraffin remover and preventer increases, its paraffin prevention rate is significantly improved. The paraffin prevention rate in Example 5 reaches 75.92%. This is because the polyacrylate pour point depressant and viscosity reducer is a comb-like polymer with two long-chain lipophilic groups and a sodium sulfonate hydrophilic group in its molecular structure. The structure of the lipophilic group is similar to that of paraffin wax and can form a eutectic with paraffin wax, preventing the wax crystals from continuing to grow. The hydrophilic group extends outward, hindering the subsequent precipitated paraffin wax from combining with it to form a three-dimensional network structure, thereby preventing the wax crystals from adhering to each other, reducing the adsorption of wax crystals, and further exerting the paraffin prevention effect. At the same time, the molecular chain of the polyacrylate pour point depressant and viscosity reducer is relatively long and is distributed throughout the entire oil phase, which can disperse the formed paraffin crystal nuclei and prevent the wax crystals from growing further.

[0069] The penetrant added to the paraffin remover and preventer has a very strong penetrating effect. After being added, the paraffin remover and preventer can fully contact and react with the wax crystals in the crude oil and wax sample, dissolve and disperse the deposited wax, and at the same time, it can be adsorbed on the surface of the wax crystals during the precipitation and growth stage of the wax crystals to prevent the wax crystals from continuing to grow and deposit, playing a certain anti-wax effect; according to the "like dissolves like" principle, wax crystals can be dissolved in the polyacrylate pour point and viscosity reducer, and xylene has a fast dissolving ability and a large saturated wax dissolving capacity, which can achieve "like dissolves like" for wax; the mutual solvent can make the various components of the paraffin remover and preventer dissolve well in the wax solvent, so that it can better contact and react with the paraffin in the crude oil, thereby accelerating the wax dissolution rate and improving the wax removal effect of the paraffin remover.

[0070] In Comparative Example 1, no polyacrylate pour point and viscosity reducer was added, and its wax prevention rate was only 32.53%. Its wax prevention and dissolving ability relied solely on the added mutual solvent and organic solvent, and the wax prevention effect was poor. Comparative Example 2 did not contain a long-chain alkane structure similar to paraffin, but contained a sodium sulfonate hydrophilic group, which could prevent wax crystals from sticking to each other and had a certain wax prevention effect, but the wax prevention effect was not as good as that of the embodiment.

[0071] Crude oil viscosity test: The test was conducted in accordance with standard SY / T0520-2008 "Determination of Crude Oil Viscosity by Rotational Viscometer Balance Method." The paraffin remover and inhibitor prepared in the examples and comparative examples were added to crude oil in a solid state at room temperature. The crude oil was heated to 80°C, kept at this temperature for 1 hour, then removed from the heat and naturally cooled to room temperature. The crude oil was placed in a sealed environment for 48 hours. The crude oil viscosity was measured using a rotary digital display viscometer at test temperatures of 20°C, 30°C, and 40°C, respectively.

[0072] Table 2 Crude oil viscosity test

[0073]

[0074] It can be seen from the test results in the above table that at low temperatures, the viscosity of crude oil continues to decrease with the increase of the content of polyacrylate pour point depressant and viscosity reducer, indicating that the addition of oil-based paraffin remover and preventive agent effectively reduces the low-temperature viscosity of crude oil. This is because the molecular structure of polyacrylate pour point depressant and viscosity reducer contains two long-chain lipophilic groups and sodium sulfonate hydrophilic groups. The structure of the lipophilic group is similar to that of paraffin wax, and can form a eutectic with paraffin wax, so that the wax crystals will not continue to grow. The hydrophilic group extends outward, hindering the subsequent precipitation of paraffin wax to combine with it to form a three-dimensional network structure, which can prevent the wax crystals from adhering to each other, causing the wax wrapped in the crude oil to dissolve. Then, it works together with mutual solvents, surfactants, etc. to penetrate into the oil along the cracks in the deposited wax and the cracks between the wax and the oil well pipe wall, thereby increasing the contact surface and improving the dissolution rate of paraffin wax, thereby reducing the viscosity of the crude oil, increasing the fluidity of the crude oil, and facilitating the smooth progress of mining work.

[0075] At 40°C, the viscosity of the crude oil in Comparative Example 1 is 170.3 mPa·s, the viscosity of the crude oil in Comparative Example 2 is 162.1 mPa·s, and the viscosity of the crude oil in Example 1 is 151.9 mPa·s. The viscosity difference between the example and the comparative example is reduced. This is because the temperature plays a major role in the influence of crude oil viscosity at this time. The higher the temperature, the lower the crude oil viscosity. This shows that the oil-based paraffin remover and paraffin inhibitor prepared by the present invention can significantly improve the low-temperature fluidity of crude oil.

[0076] Crude oil pour point test: The test was conducted in accordance with the standard SY / T0541-1994 "Determination of Crude Oil Pour Point Method." The paraffin remover and inhibitor prepared in the Examples and Comparative Examples were mixed with crude oil at a mass ratio of 1:9. The mixture was then heat treated at 60°C and cooled at a rate of 0.5°C / min. The fluidity of the sample was observed every 2°C. The highest temperature at which the sample did not flow after the test tube was placed horizontally for 5 seconds was the pour point of the crude oil.

[0077] Table 3 Crude oil pour point test

[0078]

[0079] As can be seen from the test results in the table above, the pour point of crude oil is effectively lowered with increasing content of the polyacrylate pour point depressant and viscosity reducer. The pour point of the crude oil in Comparative Example 1 is 21.6°C, while that in Example 5 is only 10.1°C, demonstrating a significant pour point depressing effect. This is because the polyacrylate pour point depressant and viscosity reducer has structural units similar to wax crystals and has good solubility in crude oil. The alkyl side chains on the molecular chain can fully interact with the paraffin wax in the crude oil, causing the molecular chain to be more extended, forming adsorption eutectics with the wax crystals. This, in turn, changes the structural morphology of the wax crystals, hindering the subsequent precipitation of paraffin wax from combining with them to form a three-dimensional network structure. This increases the space for liquid oil flow, reduces the flow resistance of the crude oil, and further exerts a pour point depressing effect.

[0080] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. An oil-based wax remover and preventer, characterized in that: The oil-based paraffin remover and inhibitor comprises the following components in parts by weight: 70-99 parts of xylene, 10-35 parts of straight-run gasoline, 2-10 parts of mutual solvent, 0.5-5 parts of surfactant, 1-15 parts of pour point and viscosity reducer, 0.1-0.5 parts of fast penetrant, wherein the mutual solvent is ethylene glycol monobutyl ether or diethylene glycol ethyl ether, and the surfactant is OP-10; The rapid penetrant is octanol polyoxyethylene ether; The preparation method of the pour point and viscosity reducing agent comprises: (1) Add sodium 3-chloro-2-hydroxypropylsulfonate, ethanol and deionized water to a reaction flask equipped with a reflux condenser, stir evenly, add allylamine hydrochloride and sodium carbonate, stir and react, and after the reaction is completed, cool to room temperature, filter, recrystallize from ethanol, and dry to obtain sodium 3-(allylamino)-2-hydroxypropane-1-sulfonate; the ratio of sodium 3-chloro-2-hydroxypropylsulfonate, allylamine hydrochloride and sodium carbonate is 1 mol: (1.05-1.2) mol: (2.5-4) mol, the reaction temperature is 75-90 ° C, and the reaction time is 8-16 h; (2) Add sodium 3-(allylamino)-2-hydroxypropane-1-sulfonate and toluene to a reaction flask equipped with a reflux condenser and a water separator, stir evenly, add triethylamine and long-chain alkyl acyl chloride, heat to 105-120°C and react for 8-14 hours. When no water is produced in the water separator, cool, extract and separate the liquid, concentrate the organic phase to obtain 3-(N-allyl-N-long-chain alkanoylamino)-2-long-chain alkanoyloxypropane-1-sulfonate. The long-chain alkyl acyl chloride is any one of palmitoyl chloride, heptadecanoyl chloride, stearyl chloride, and nonadecanoyl chloride. The ratio of sodium 3-(allylamino)-2-hydroxypropane-1-sulfonate, triethylamine, and long-chain alkyl acyl chloride is 1 mol: (2.1-2.2) mol: (2.2-2.5) mol. The structural formula of the sodium 3-(N-allyl-N-long-chain alkanoylamino)-2-long-chain alkanoyloxypropane-1-sulfonate is: , where n is an integer between 14 and 17; (3) Add sodium 3-(N-allyl-N-long-chain alkanoylamino)-2-long-chain alkanoyloxypropane-1-sulfonate and toluene to a reaction flask equipped with a reflux condenser, stir evenly, add N,N'-methylenebisacrylamide and initiator ammonium persulfate, stir to react, and after the reaction is completed, cool to room temperature and concentrate to obtain a pour point and viscosity reducer; the ratio of sodium 3-(N-allyl-N-long-chain alkanoylamino)-2-long-chain alkanoyloxypropane-1-sulfonate, N,N'-methylenebisacrylamide, and ammonium persulfate is 1 mol: (0.03-0.06) mol: (0.02-0.05) mol, the reaction temperature is 60-80 ° C, and the reaction time is 4-10 h.

2. A method for preparing the oil-based paraffin remover and inhibitor according to claim 1, characterized in that: The preparation method is carried out according to the following steps: adding xylene, straight-run gasoline, a mutual solvent and a surfactant into a reaction bottle, stirring at a temperature of 20-35° C. and a rotation speed of 600-1000 r / min for 10-30 minutes, adding a rapid penetrant after uniform dispersion, continuing stirring for 5-20 minutes, then adding a pour point and viscosity reducer, stirring evenly, and obtaining an oil-based paraffin remover and inhibitor.

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