Environment-friendly oil extraction well paraffin remover and preparation method thereof

Abstract

The invention relates to the technical field of oilfield chemistry, in particular to an environment-friendly oil extraction well paraffin remover and a preparation method thereof. The environment-friendly paraffin remover for the oil extraction well is prepared from the following components in percentage by weight: 2 to 5 percent of specific lipase, 0.5 to 2 percent of acylated nano cellulose, 15 to 20 percent of D-limonene, 10 to 15 percent of methyl laurate, 3 to 6 percent of rhamnolipid, 8 to 10 percent of alkyl glycoside, 4 to 6 percent of n-butyl alcohol, 3 to 6 percent of Tris-HCl buffer solution, 5 to 7 percent of sorbitol, 3 to 6 percent of glycerol, 0.1 to 0.3 percent of calcium gluconate and 21.7 to 48.4 percent of deionized water. Through the synergistic effect of the bio-based solvent, the specific lipase and the acylated nano-cellulose, physical stripping, physical dissolution and biological enzymolysis of wax deposition are achieved, the wax deposition can be rapidly, deeply and thoroughly removed, meanwhile, aggregation and deposition of wax crystals can be effectively inhibited through the acylated nano-cellulose left on the tube wall, and the wax deposition can be effectively inhibited. The long-acting paraffin control agent has excellent long-acting paraffin control capability, and the main components have good biodegradability, do not contain persistent pollutants, and have extremely low ecological toxicity.

Description

Technical Field

[0001] This invention relates to the field of oilfield chemical technology, specifically to an environmentally friendly oil well dewaxing agent and its preparation method. Background Technology

[0002] Oil well dewaxing agents are chemical agents specifically designed to remove and prevent paraffin deposits that form in downhole equipment, tubing, and pipelines during oil well production. During oil production, crude oil is not a single liquid; under high temperature and pressure underground, substances such as paraffin, gum, and asphalt dissolve in it. As the crude oil is lifted from the formation to the surface, its temperature gradually decreases. Once the temperature drops below the precipitation point of paraffin, the dissolved paraffin crystallizes and accumulates on the inner walls of tubing, sucker rods, and equipment. This reduces the flow area of ​​the tubing, increases the resistance to crude oil flow, increases the load on the pumping unit, and can even completely block the pipeline. Therefore, dewaxing agents are essential for ensuring the healthy and stable production of oil wells.

[0003] Existing oil well dewaxing agents primarily use aromatic hydrocarbons such as benzene, toluene, and xylene as solvents. These are carcinogenic and highly toxic to humans and the environment. Once leaked, they can cause long-term and difficult-to-remediate pollution to soil and groundwater. They are also difficult to degrade by microorganisms in the natural environment, posing a risk of bioaccumulation. Furthermore, existing oil well dewaxing agents have a simple mechanism, slow action, limited dewaxing rate, and lack of long-term effectiveness. They can also damage the oil wettability of reservoir rocks, thereby reducing reservoir permeability and affecting production. Once they enter the crude oil system, they can interfere with crude oil demulsification and dehydration, increasing the difficulty and cost of subsequent crude oil processing.

[0004] To address the above problems, the present invention provides a solution. Summary of the Invention

[0005] The purpose of this invention is to provide an environmentally friendly dewaxing agent for oil wells and its preparation method, which has the advantages of fast dewaxing, high efficiency and long-term effectiveness.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: An environmentally friendly oil well dewaxing agent is composed of the following components by weight percentage: 2-5% specific lipase, 0.5-2% acylated nanocellulose, 15-20% D-limonene, 10-15% methyl laurate, 3-6% rhamnolipid, 8-10% alkyl glycoside, 4-6% n-butanol, 3-6% Tris-HCl buffer, 5-7% sorbitol, 3-6% glycerol, 0.1-0.3% calcium gluconate, and 21.7-48.4% deionized water; The preparation method of acylated nanocellulose includes the following steps: A1: Place microcrystalline cellulose in a vacuum drying oven, set the temperature of the vacuum drying oven to 105℃, and vacuum dry for 4 hours. After drying, take it out and transfer it to a mortar and grind for 15 minutes. After grinding, pass it through a 100-mesh filter sieve. Put the un-sieved microcrystalline cellulose back into the mortar and grind for 10 minutes. After grinding, repeat the process of passing it through a 100-mesh filter sieve until all the microcrystalline cellulose passes through the sieve. A2: Dry the planetary ball mill jar for 10 minutes. Mix the sieved microcrystalline cellulose, acetic anhydride and 4-dimethylaminopyridine evenly and add them to the dried planetary ball mill jar. Then add the grinding balls. After the grinding balls are added, immediately seal the ball mill jar to ensure good airtightness. A3: Start the planetary ball mill, set the ball mill revolution speed to 400 rpm, and ball mill for 6-8 hours. During the ball milling process, use the ball milling mode of 15 minutes forward rotation, 5 minutes pause, and 15 minutes reverse rotation. After the ball milling is completed, close the ball mill jar and allow it to cool naturally to room temperature. A4: After cooling, transfer the material in the ball mill jar to a beaker, add 500 ml of anhydrous ethanol to the beaker to obtain a primary mixture, transfer the primary mixture to a centrifuge tube, balance the centrifuge, set the centrifuge speed to 8000 rpm, centrifuge for 15 min, discard the supernatant after centrifugation, add 400 ml of anhydrous ethanol to the precipitate, centrifuge again, discard the supernatant after centrifugation, repeat twice to obtain a secondary mixture; A5: Add the intermediate mixture to deionized water, then transfer it to a probe sonicator. Set the sonication power to 600W, sonicate for 2 seconds, pause for 3 seconds, and sonicate for a total of 15 minutes. After sonication, dispense the mixture into freeze-drying boxes and pre-freeze them in a -80℃ freezer for 15 minutes. After pre-freezing, transfer the mixture to a freeze dryer. Set the freeze dryer temperature to -50℃ and the vacuum degree to 5Pa. Freeze-dry for 48 hours to obtain acylated nanocellulose.

[0007] Furthermore, the molar ratio of the sieved microcrystalline cellulose, acetic anhydride, and 4-dimethylaminopyridine in step A2 is 1:(4.5-7.5):(0.08-0.15); the mass ratio of the sieved microcrystalline cellulose to the grinding balls in step A2 is 1:40; and the mass ratio of the final mixture to deionized water in step A5 is 1:100. Furthermore, a method for preparing an environmentally friendly oil well dewaxing agent includes the following steps: B1: Add 70% of the total formulation amount of deionized water to a main reactor, set the stirrer speed to 300 rpm and slowly heat to 30°C, then add sorbitol, glycerol and calcium gluconate in sequence, stir for 15 min, add Tris-HCl buffer after stirring, and repeat stirring for 15 min to obtain the basic aqueous phase solution; B2: Take 15% of the basic aqueous solution and transfer it to another small reactor. Add acylated nanocellulose and then transfer it to a high-speed shear machine. Set the speed of the high-speed shear machine to 5000 rpm and stir for 5 minutes to obtain nano slurry. Transfer the nano slurry to the basic aqueous solution and set the speed of the stirrer in the main reactor to 400 rpm. Stir continuously for 30 minutes. B3: Add D-limonene, methyl lauryl ester, rhamnolipid, alkyl glycoside and n-butanol to another reactor, set the stirrer speed to 300 rpm, and stir for 30 min to obtain the oil phase matrix; B4: Using a dropping funnel, slowly add the oil phase matrix to the main reactor at a rate of 3 drops / s. During the dropping process, set the stirring speed of the main reactor to 300 rpm until all the oil phase matrix is ​​added to the main reactor. After all the oil phase matrix is ​​added, set the stirring speed of the main reactor to 1000 rpm and stir continuously for 30 minutes to obtain a microemulsion. B5: Set the stirring speed of the main reactor to 200 rpm, then add the specific lipase to the main reactor, followed by the remaining 30% of the total formula amount of deionized water. Keep the stirring speed unchanged and continue stirring for 20 minutes. During the stirring process, use a pH adjuster to adjust the pH to 8.0-8.2, then let it stand for 2 hours. After standing, the environmentally friendly oil well dewaxing agent is obtained.

[0008] Furthermore, the pH adjuster mentioned in step B5 is a 1% citric acid solution and a 1% sodium bicarbonate solution; the specific lipase is a mixed enzyme consisting of alkane hydrogenase, lipase, alcohol dehydrogenase, aldehyde dehydrogenase and peroxidase, wherein the mass ratio of alkane hydrogenase, lipase, alcohol dehydrogenase, aldehyde dehydrogenase and peroxidase is 4:3:1:1:1; In summary, due to the adoption of the above technical solutions, the beneficial effects of this invention are as follows: this invention achieves physical stripping, physical dissolution, and bio-enzymatic hydrolysis of wax deposits through the synergistic effect of bio-based solvents, specific lipases, and acylated nanocellulose. It can quickly, deeply, and thoroughly remove wax deposits. At the same time, the acylated nanocellulose remaining on the pipe wall can effectively inhibit the aggregation and deposition of wax crystals, exhibiting excellent long-lasting anti-wax capabilities. Furthermore, the main components have good biodegradability, do not contain persistent pollutants, and have extremely low ecotoxicity. Detailed Implementation

[0009] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below with reference to specific embodiments.

[0010] Unless otherwise specified, the experimental methods used in the following examples are conventional methods, performed according to the techniques or conditions described in the literature in this field or according to the product instructions. Unless otherwise specified, the materials and reagents used in the following examples are commercially available.

[0011] Example 1 1: Place 50g of microcrystalline cellulose in a vacuum drying oven, set the temperature of the vacuum drying oven to 105℃, and vacuum dry for 4 hours. After drying, take it out and transfer it to a mortar and grind for 15 minutes. After grinding, pass it through a 100-mesh filter sieve. Put the un-sieved microcrystalline cellulose back into the mortar and grind for 10 minutes. After grinding, repeat the process of passing it through a 100-mesh filter sieve until all the microcrystalline cellulose passes through the sieve. 2: Dry the planetary ball mill jar for 10 minutes. Mix 50g of sieved microcrystalline cellulose, 141.6g of acetic anhydride and 3.01g of 4-dimethylaminopyridine evenly and add them to the dried planetary ball mill jar. Then add 2kg of grinding balls. After adding the grinding balls, immediately seal the ball mill jar to ensure good airtightness. 3: Start the planetary ball mill, set the ball mill revolution speed to 400 rpm, and ball mill for 6 hours. During the ball milling process, use the ball milling mode of 15 minutes forward rotation, 5 minutes pause, and 15 minutes reverse rotation. After the ball milling is completed, close the ball mill jar and allow it to cool naturally to room temperature. 4: After cooling, transfer the material in the ball mill jar to a beaker, add 500 ml of anhydrous ethanol to the beaker to obtain the primary mixture, transfer the primary mixture to a centrifuge tube, balance the centrifuge, set the centrifuge speed to 8000 rpm, centrifuge for 15 min, discard the supernatant after centrifugation, add 400 ml of anhydrous ethanol to the precipitate, centrifuge again, discard the supernatant after centrifugation, repeat twice to obtain the intermediate mixture; 5: Add the intermediate mixture to deionized water, then transfer it to a probe sonicator. Set the sonication power to 600W, sonicate for 2 seconds, pause for 3 seconds, and sonicate for a total of 15 minutes. After sonication, dispense the mixture into freeze-drying boxes and pre-freeze in a -80℃ freezer for 15 minutes. After pre-freezing, transfer the mixture to a freeze dryer. Set the freeze dryer temperature to -50℃ and the vacuum degree to 5Pa. Freeze-dry for 48 hours to obtain 54g of acylated nanocellulose prepared in Example 1.

[0012] Table 1. Reagent parameters used in Example 1

[0013] Example 2 1: Place 200g of microcrystalline cellulose in a vacuum drying oven, set the temperature of the vacuum drying oven to 105℃, and vacuum dry for 4 hours. After drying, take it out and transfer it to a mortar and grind for 15 minutes. After grinding, pass it through a 100-mesh filter sieve. Put the un-sieved microcrystalline cellulose back into the mortar and grind for 10 minutes. After grinding, repeat the process of passing it through a 100-mesh filter sieve until all the microcrystalline cellulose passes through the sieve. 2: Dry the planetary ball mill jar for 10 minutes. Mix 200g of sieved microcrystalline cellulose, 1180.4g of acetic anhydride and 28.24g of 4-dimethylaminopyridine evenly and add them to the dried planetary ball mill jar. Then add 8kg of grinding balls. After adding the grinding balls, immediately seal the ball mill jar to ensure good airtightness. 3: Start the planetary ball mill, set the ball mill revolution speed to 400 rpm, and ball mill for 8 hours. During the ball milling process, use the ball milling mode of 15 minutes forward rotation, 5 minutes pause, and 15 minutes reverse rotation. After the ball milling is completed, close the ball mill jar and allow it to cool naturally to room temperature. 4: After cooling, transfer the material in the ball mill jar to a beaker, add 500 ml of anhydrous ethanol to the beaker to obtain the primary mixture, transfer the primary mixture to a centrifuge tube, balance the centrifuge, set the centrifuge speed to 8000 rpm, centrifuge for 15 min, discard the supernatant after centrifugation, add 400 ml of anhydrous ethanol to the precipitate, centrifuge again, discard the supernatant after centrifugation, repeat twice to obtain the intermediate mixture; 5: Add the intermediate mixture to deionized water, then transfer it to a probe sonicator. Set the sonication power to 600W, sonicate for 2 seconds, pause for 3 seconds, and sonicate for a total of 15 minutes. After sonication, dispense the mixture into freeze-drying boxes and pre-freeze in a -80℃ freezer for 15 minutes. After pre-freezing, transfer the mixture to a freeze dryer. Set the freeze dryer temperature to -50℃ and the vacuum degree to 5Pa. Freeze-dry for 48 hours to obtain 213g of acylated nanocellulose prepared in Example 2.

[0014] Table 2, Reagent Parameters Used in Example 2

[0015] Example 3 1: Add 3388g of deionized water to a main reactor, set the stirrer speed to 300rpm and slowly heat to 30℃, then add 500g of sorbitol, 300g of glycerol and 10g of calcium gluconate in sequence, stir for 15min, after stirring is complete, add 300g of Tris-HCl buffer, and repeat stirring for 15min to obtain 4498g of basic aqueous phase solution; 2: Take 674.7g of aqueous solution and transfer it to another small reactor. Add 50g of acylated nanocellulose prepared in Example 1. Then transfer it to a high-speed shear machine. Set the speed of the high-speed shear machine to 5000rpm and stir for 5min to obtain nano slurry. Transfer the nano slurry to the basic aqueous solution. Set the speed of the stirrer in the main reactor to 400rpm and stir continuously for 30min. 3: Add 1.5 kg D-limonene, 1 kg methyl laurate, 300 g rhamnolipid, 800 g alkyl glycoside and 400 g n-butanol to another reactor, set the stirrer speed to 300 rpm, and stir for 30 min to obtain the oil phase matrix. 4: Using a dropping funnel, slowly add the oil phase matrix to the main reactor at a rate of 3 drops / s. During the dropping process, set the stirring speed of the main reactor to 300 rpm until all the oil phase matrix is ​​added to the main reactor. After all the oil phase matrix is ​​added, set the stirring speed of the main reactor to 1000 rpm and stir continuously for 30 minutes to obtain a microemulsion. 5: Set the stirring speed of the main reactor to 200 rpm, then add 200g of specific lipase to the main reactor, followed by 1452g of deionized water. Keep the stirring speed constant and continue stirring for 20 minutes. During the stirring process, adjust the pH to 8.0 using 1% citric acid solution and 1% sodium bicarbonate solution. Then let it stand for 2 hours. After standing, the environmentally friendly oil well dewaxing agent prepared in Example 3 is obtained.

[0016] Table 3. Reagent parameters used in Example 3

[0017] Example 4 1: Add 1519g of deionized water to a main reactor, set the stirrer speed to 300rpm and slowly heat to 30℃, then add 700g of sorbitol, 600g of glycerol and 30g of calcium gluconate in sequence, stir for 15min, after stirring is complete, add 600g of Tris-HCl buffer, and repeat stirring for 15min to obtain the basic aqueous phase solution; 2: Take 517.35g of aqueous solution and transfer it to another small reactor. Add 200g of acylated nanocellulose prepared in Example 2, and then transfer it to a high-speed shear machine. Set the speed of the high-speed shear machine to 5000rpm and stir for 5min to obtain nano slurry. Transfer the nano slurry to the basic aqueous solution and set the speed of the stirrer in the main reactor to 400rpm. Stir continuously for 30min. 3: Add 2 kg D-limonene, 1.5 kg methyl laurate, 600 g rhamnolipid, 1 kg alkyl glycoside and 600 g n-butanol to another reactor, set the stirrer speed to 300 rpm, and stir for 30 min to obtain the oil phase matrix. 4: Using a dropping funnel, slowly add the oil phase matrix to the main reactor at a rate of 3 drops / s. During the dropping process, set the stirring speed of the main reactor to 300 rpm until all the oil phase matrix is ​​added to the main reactor. After all the oil phase matrix is ​​added, set the stirring speed of the main reactor to 1000 rpm and stir continuously for 30 minutes to obtain a microemulsion. 5. Set the stirring speed of the main reactor to 200 rpm, then add 500g of specific lipase to the main reactor, followed by 651g of deionized water. Keep the stirring speed constant and continue stirring for 20 minutes. During the stirring process, adjust the pH to 8.2 using 1% citric acid solution and 1% sodium bicarbonate solution. Then let it stand for 2 hours. After standing, the environmentally friendly oil well dewaxing agent prepared in Example 4 is obtained.

[0018] Table 4. Reagent parameters used in Example 4

[0019] Comparative Example 1 Example 1 of Chinese Patent Publication No. CN108467716A was selected as Comparative Example 1.

[0020] Comparative Example 2 Example 1 of Chinese Patent Publication No. CN111763508A was selected as Comparative Example 2.

[0021] Basic physical and chemical performance testing The unblocking agents prepared in Example 3, Example 4, Comparative Example 1 and Comparative Example 2 were placed in transparent glass tubes and observed under natural light. The pH value was then directly measured using a calibrated precision pH meter. The surface tension of the unblocking agents prepared in Examples 3, 4, Comparative Example 1 and Comparative Example 2 was measured using a fully automated surface tension meter. The agents were then diluted to 10% (usage concentration) with deionized water and their surface tension was measured at a constant temperature of 25°C.

[0022] Table 5. Results of Basic Physicochemical Properties Tests

[0023] Wax removal rate test After thoroughly cleaning, drying and cooling the metal sample with petroleum ether, weigh it using an analytical balance and record the initial weight. Heat the paraffin wax until it melts into a liquid state. Hold one end of the sample with tweezers and vertically immerse it in the molten paraffin wax for 3 seconds. Slowly lift it out and let it stand in the air until the paraffin wax completely solidifies, forming a uniform wax film on the surface of the sample. After the sample cools to room temperature, weigh it again using an analytical balance and record the mass after waxing. 100ml of test sample was placed into a beaker. The constant temperature water bath shaker was then set to 50℃. The beaker containing the test sample was placed in the water bath and preheated to 50℃. The wax-coated test piece was tied with a thin thread and completely immersed in the wax removal agent solution, ensuring that the test piece did not contact the container wall. The shaking function was turned on and the shaking frequency was set to 100 rpm. The reaction was carried out at a constant temperature for 4 hours. The wax removal rate was recorded at 0.5h, 1h and 4h. After the constant temperature reaction is completed, take out the test piece, hold it with tweezers, and gently shake it in flowing deionized water to rinse away the residual reagent and the wax that has been removed from the surface. Then put the test piece into an oven at 50°C to dry to constant weight. After drying, take it out and put it in a desiccator to cool to room temperature. Use an analytical balance to accurately weigh the cleaned test piece to obtain the wax removal rate. Each test sample is tested 3 times and the average value is taken. Table 6. Results of wax removal rate test

[0024] Wax-deposited loop test Take four sets of stainless steel or transparent glass tubes, each 5 meters long and with an inner diameter similar to that of the tubing, coil them into a ring, and place them in a temperature-controlled water bath. Then, set up a circulation system including a pump, storage tank, flow meter, and valves to drive the test fluid circulation. Set the water bath temperature to 30°C to simulate the low-temperature pipe wall environment in the upper part of the wellbore and induce wax deposition. Set the storage tank heater temperature to 70°C to ensure that the wax crystals are completely dissolved before the crude oil enters the ring. A pressure sensor was used to monitor the pressure difference between the two ends of the loop. An increase in pressure difference indicates that wax buildup leads to an increase in flow resistance. At the same time, a temperature sensor was set up to record the test temperature in real time. The wax removal agents prepared in Examples 3, 4, Comparative Example 1 and Comparative Example 2 were prepared into a 10% application solution using deionized water. First stage: Add waxy crude oil to the loop system, raise the temperature of the storage tank to 70°C, lower the temperature of the water bath to 30°C, turn on the circulation pump and run it at a flow rate of 0.5 m / s for 12 hours. The low temperature of the pipe wall will cause wax crystals to precipitate and deposit, and the system pressure difference will continue to rise until it reaches a stable high value. Record this initial wax deposition pressure difference. Second stage: Stop the circulation, drain the crude oil from the system, and then inject 2L of the wax removal agent prepared in Example 3, Example 4, Comparative Example 1 and Comparative Example 2 into the four groups of systems to prepare a 10% application liquid. Start the circulation pump and run it at a speed of 0.1m / s for 4 hours to simulate the well shut-in wax removal process. The water bath temperature remains unchanged. After the wax removal process is completed, use deionized water to flush the pipeline, record the pressure difference drop rate and observe the pipe wall surface. Third stage: Clean waxy crude oil is added to the pipeline again, and the first stage is repeated. After the repetition is completed, the change of system pressure difference over time is recorded for 8 hours. After the experiment, the loop is disassembled, and the amount of wax deposited on the pipe wall is directly observed and weighed.

[0025] Table 7. Results of wax deposition ring test

[0026] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. An environmentally friendly oil well dewaxing agent, characterized in that, consists of the following weight percentage components: 2-5% specific lipase, 0.5-2% acylated nanocellulose, 15-20% D-limonene, 10-15% methyl laurate, 3-6% rhamnolipid, 8-10% alkyl glycoside, 4-6% n-butanol, 3-6% Tris-HCl buffer, 5-7% sorbitol, 3-6% glycerol, 0.1-0.3% calcium gluconate, 21.7-48.4% deionized water; The preparation method of the acylated nanocellulose comprises the following steps: A1: Take the microcrystalline cellulose and place it in a vacuum drying oven, set the temperature of the vacuum drying oven to 105℃, and vacuum dry for 4h. After drying, take it out and transfer it to a mortar, grind for 15min, and after grinding, pass it through a 100-mesh sieve. The microcrystalline cellulose that does not pass through the sieve is placed back in the mortar and ground for 10min. After grinding, repeat the process of passing through a 100-mesh sieve until all the microcrystalline cellulose is sieved; A2: Dry the planetary ball mill jar for 10min, then add the sieved microcrystalline cellulose, acetic anhydride, and 4-dimethylaminopyridine. Then add the grinding balls, immediately seal the ball mill jar to ensure good airtightness; A3: Start the planetary ball mill, set the revolution speed to 400rpm, and mill for 6-8h. During the milling process, use the milling mode of forward rotation for 15min, pause for 5min, and reverse rotation for 15min. After milling, turn off the ball mill jar and cool it to room temperature naturally; A4: After cooling, transfer the material in the ball mill jar to a beaker, add 500ml of anhydrous ethanol to the beaker to obtain a primary mixture, transfer the primary mixture to a centrifuge tube, balance the centrifuge, set the centrifuge speed to 8000rpm, and centrifuge for 15min. After centrifugation, discard the supernatant, add 400ml of anhydrous ethanol to the precipitate, centrifuge again, discard the supernatant after centrifugation, and repeat the process 2 more times to obtain an intermediate mixture; A5: Add the intermediate mixture to deionized water, then transfer it to a probe ultrasonic instrument, set the ultrasonic power to 600W, ultrasonic for 2s, pause for 3s, and ultrasonic for a total of 15min. After ultrasonic, dispense it into freeze-drying boxes, place it in a-80℃ refrigerator for pre-freezing for 15min, transfer it to a freeze dryer after pre-freezing, set the temperature of the freeze dryer to-50℃, the vacuum degree to 5Pa, and freeze dry for 48h to obtain acylated nanocellulose.

2. The environment-friendly oil well paraffin remover according to claim 1, characterized in that, The specific lipase is a mixture of alkane hydrogenase, lipase, alcohol dehydrogenase, aldehyde dehydrogenase, and peroxidase, and the mass ratio of alkane hydrogenase, lipase, alcohol dehydrogenase, aldehyde dehydrogenase, and peroxidase is 4:3:1:1:

1.

3. The environment-friendly oil well paraffin remover according to claim 1, characterized in that, The molar ratio of the sieved microcrystalline cellulose, acetic anhydride, and 4-dimethylaminopyridine in step A2 is 1:(4.5-7.5):(0.08-0.15).

4. The environment-friendly oil well paraffin remover according to claim 1, characterized in that, The mass ratio of the base material and the grinding balls in step A2 is 1:

40.

5. The environment-friendly oil well paraffin remover according to claim 1, characterized in that, The mass ratio of the final mixture and deionized water in step A5 is 1:

100.

6. The preparation method of the environment-friendly oil well paraffin remover according to claim 1, characterized in that, comprises the following steps: B1: In one main reactor, add 70% of the total amount of deionized water, set the stirring speed to 300 rpm and slowly heat to 30°C, then add sorbitol, glycerol and calcium gluconate in turn, stir for 15 min, after stirring, add Tris-HCl buffer solution, repeat stirring for 15 min to obtain a basic aqueous solution; B2: Take 15% of the basic aqueous solution and transfer it to another small reactor, add acylated nanocellulose, then transfer it to a high-speed shearing machine, set the speed to 5000 rpm, stir for 5 min to obtain a nanosuspension, then transfer the nanosuspension to the basic aqueous solution, set the stirring speed of the main reactor to 400 rpm, and continue stirring for 30 min; B3: In another reactor, add D-limonene, methyl laurate, rhamnolipid, alkyl glycoside and n-butanol, set the stirring speed to 300 rpm, stir for 30 min to obtain an oil phase matrix; B4: Use a dropping funnel to slowly add the oil phase matrix to the main reactor at a rate of 3 drops / s, set the stirring speed of the main reactor to 300 rpm during the dropping process until all the oil phase matrix is added to the main reactor, then set the stirring speed of the main reactor to 1000 rpm, continue stirring for 30 min to obtain a microemulsion; B5: Set the stirring speed of the main reactor to 200 rpm, then add specific lipase to the main reactor, then add the remaining 30% of the total amount of deionized water, keep the stirring speed unchanged, continue stirring for 20 min, adjust the pH to 8.0-8.2 with a pH adjuster during stirring, then stand for 2 h, and obtain an environmentally friendly oil well wax remover after standing.

7. The preparation method of the environment-friendly oil well paraffin remover according to claim 6, characterized in that, The pH adjuster in step B5 is a 1% citric acid solution and a 1% sodium bicarbonate solution.

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