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CN-121975503-A - Efficient paraffin removal and blocking removal agent for high wax content oil well and preparation method thereof

CN121975503ACN 121975503 ACN121975503 ACN 121975503ACN-121975503-A

Abstract

The invention belongs to the technical field of oilfield chemistry, and particularly relates to a high-efficiency paraffin removal blocking remover for a high-wax-content oil well and a preparation method thereof. The fluorocarbon modified star branched polyether amine is prepared by reacting trifunctional polyether amine with perfluorohexyl ethyl isocyanate, can quickly penetrate and destroy a wax crystal structure, and the zwitterionic modified cardanol polymer is prepared by copolymerizing cardanol after acrylic acid esterification and then quaternizing, and can stably disperse wax crystals and inhibit deposition of the wax crystals. The blocking remover has excellent blocking removing capability to high-carbon paraffin wax based on a synergistic dispersion mechanism, high blocking removing rate and good temperature resistance and salt resistance, and field application shows that the blocking remover can effectively solve the problem of wax blocking of oil wells and pipelines.

Inventors

  • WU HONGJUN
  • SUN JINSHENG
  • LV KAIHE
  • BAI YINGRUI
  • LIU JINGPING
  • PANG XUEYU
  • WANG JINTANG
  • HUANG XIANBIN

Assignees

  • 中国石油大学(华东)

Dates

Publication Date
20260505
Application Date
20251223

Claims (10)

  1. 1. The preparation method of the efficient paraffin removal blocking remover for the high wax-containing oil well is characterized by comprising the following steps of: S1, adding kerosene, dimethylbenzene and n-butanol into a reaction kettle at room temperature, and stirring to obtain a mixed solvent, adding fluorocarbon modified star-branched polyether amine and zwitterionic modified cardanol polymer into the mixed solvent, and continuously stirring in a water bath at 40-45 ℃ to obtain viscous liquid; S2, adding sodium alkenyl sulfonate, fatty alcohol polyoxyethylene ether, disodium ethylenediamine tetraacetate, benzotriazole and ammonium persulfate into the viscous liquid, heating to 50-55 ℃, continuously stirring to obtain a product, and cooling the product to room temperature.
  2. 2. The method for preparing the efficient paraffin removal and plugging removal agent for the high-wax-content oil well, according to claim 1, wherein in the step S1, the continuous stirring time is 60-90min in a water bath at 40-45 ℃.
  3. 3. The method for preparing the efficient paraffin removal and blocking remover for the high-wax-content oil well, as claimed in claim 1, wherein in the step S2, the stirring is continued for 45-60min.
  4. 4. The method for preparing the efficient paraffin removal and blocking remover for the high wax content oil well, which is disclosed in claim 1, is characterized in that the method for preparing the fluorocarbon modified star-branched polyether amine comprises the following steps: A1, dissolving trifunctional polyether amine in dry anhydrous toluene under the protection of dry nitrogen, heating to 48-52 ℃, dropwise adding perfluorohexyl ethyl isocyanate and dibutyltin dilaurate under stirring, heating to 68-72 ℃ after dropwise adding, and continuing stirring for reaction to obtain a reaction mixture; A2, cooling the reaction mixture to room temperature, then adding the cooled reaction mixture into n-hexane under stirring to obtain a solid product, washing the solid product with n-hexane, and drying the solid product in vacuum at 48-52 ℃.
  5. 5. The method for preparing a high-efficiency paraffin removal and blocking remover for high-wax-content wells according to claim 4, wherein in the step A1, the molar ratio of the trifunctional polyetheramine to the perfluorohexyl ethyl isocyanate is 1 (3.0-3.3).
  6. 6. The method for preparing the efficient paraffin removal and blocking remover for high-wax-content wells according to claim 4, wherein in the step A2, the time of vacuum drying at 48-52 ℃ is 12-24h.
  7. 7. The method for preparing the efficient paraffin removal and blocking remover for the high wax content oil well, which is characterized by comprising the following steps of: B1, dissolving acryloyl chloride in anhydrous tetrahydrofuran under the protection of nitrogen, stirring to obtain an acryloyl chloride solution, dropwise adding the acryloyl chloride solution into a reaction bottle containing cardanol and triethylamine, reacting at 0-5 ℃, filtering after the reaction is finished, washing filtrate with hydrochloric acid solution, saturated sodium bicarbonate solution and saturated saline water in sequence, drying an organic phase through anhydrous sodium sulfate, performing rotary evaporation to obtain a crude product, purifying the crude product through silica gel column chromatography to obtain a cardanol acrylate monomer, dissolving cardanol acrylate monomer, N- (3-dimethylaminopropyl) methacrylamide and hydroxyethyl acrylate in a mixed solvent of tetrahydrofuran and isopropanol under the protection of nitrogen, adding 3-mercaptopropionic acid, stirring, heating to 68-72 ℃, dropwise adding a tetrahydrofuran solution of azodiisobutyronitrile, obtaining a reaction liquid, evaporating and concentrating the reaction liquid, dropwise adding N-hexane under stirring, performing centrifugal separation to obtain a solid product, washing the solid product with N-hexane, and performing vacuum drying to obtain a polymer containing tertiary amine groups; And B2, redissolving a polymer containing tertiary amino groups in anhydrous N, N-dimethylformamide, heating to 58-62 ℃, dropwise adding an anhydrous N, N-dimethylformamide solution of 1, 3-propane sultone under stirring, continuing stirring for reaction at 60-65 ℃ after the dropwise adding is finished to obtain a reaction mixture, cooling the reaction mixture to room temperature, dropwise adding acetone under stirring for precipitation, centrifuging, collecting a solid product, washing the solid product with acetone to obtain a washed solid product, redissolving the washed solid product in deionized water, filling the deionized water into a dialysis bag, dialyzing to obtain a dialysate, and freeze-drying the dialysate.
  8. 8. The preparation method of the efficient paraffin removal blocking remover for the high-wax-content wells, which is characterized in that in the step B1, the mass ratio of cardanol to acryloyl chloride to triethylamine is 1 (0.75-0.85) (0.80-0.90), and the mass ratio of cardanol acrylate monomer to N- (3-dimethylaminopropyl) methacrylamide to hydroxyethyl acrylate to 3-mercaptopropionic acid to azodiisobutyronitrile is 1 (1.5-2.5) (0.5-1.5) (0.01-0.04) (0.01-0.03).
  9. 9. The method for preparing a high efficiency paraffin removal and plugging removal agent for a high wax content well according to claim 7, wherein in the step B2, the stirring reaction is continued for 24-36 hours at 60-65 ℃.
  10. 10. The efficient paraffin removal plugging removing agent for the high-wax-content oil well, which is prepared by the preparation method of the efficient paraffin removal plugging removing agent for the high-wax-content oil well, according to any one of claims 1-9, is characterized by comprising, by weight, 10-20 parts of fluorocarbon modified star-branched polyether amine, 8-15 parts of zwitterionic modified cardanol polymer, 30-50 parts of kerosene, 10-20 parts of xylene, 5-12 parts of n-butanol, 3-8 parts of sodium alkenyl sulfonate, 2-6 parts of fatty alcohol polyoxyethylene ether, 1-3 parts of disodium ethylenediamine tetraacetate, 1-2 parts of benzotriazole and 0.5-2 parts of ammonium persulfate.

Description

Efficient paraffin removal and blocking removal agent for high wax content oil well and preparation method thereof Technical Field The invention belongs to the technical field of oilfield chemistry, and particularly relates to a high-efficiency paraffin removal and blocking remover for a high-wax-content oil well and a preparation method thereof. Background In the exploitation process of high-wax-content oil wells, the blockage of a shaft and a gathering pipeline caused by paraffin deposition is always a great technical problem for restricting the efficient development of oil fields. As the oil field exploitation enters the middle and later stages, the temperature and pressure of the oil well gradually decrease, and the high-carbon-number paraffin components in the crude oil are more easily separated out and deposited and attached to the pipe wall, so that a compact and hard wax deposition layer is formed. These deposits not only greatly increase the flow resistance, resulting in a drastic drop in production, but also cause serious accidents such as equipment damage, pipe condensation and even oil well rejection. At present, the traditional methods such as thermal paraffin removal and mechanical paraffin removal are mainly adopted on site, but the thermal method has the inherent defects of high energy consumption, complex construction, limited deep blocking effect and the like, and the mechanical rule can damage shaft equipment and can not fundamentally inhibit redeposition of paraffin. Although the chemical blocking removal technology has the advantages of simple construction, wide application range and the like, the blocking removal efficiency of the conventional chemical agent on the paraffin with high carbon number and high melting point is generally not ideal, and the current blocking removal requirement of the high wax-containing oil well is difficult to meet. The existing chemical blocking remover is mainly based on a single dissolution mechanism, and realizes blocking removal through the dissolution of the paraffin by the solvent, and the blocking remover has a certain effect on medium-low carbon paraffin, but is not attractive for high carbon paraffin with multiple carbon numbers and high melting point. The chain length of the high-carbon paraffin molecules is regular and compact, the conventional solvent molecules are difficult to penetrate into the high-carbon paraffin molecules, and the blocking removal rate is generally low. In addition, some plugging removers on the market, which mainly use surfactants, can carry paraffin through emulsification, but have poor stability in high-temperature and high-mineralization stratum environments, are easy to break and lose effectiveness, and have corrosion risks on metal equipment. In recent years, research and development of composite blocking remover are attempted, but most of the agents stay on the physical mixing level, and the synergistic effect of different functional components cannot be realized from the molecular structure design, so that the blocking removing efficiency in practical application is limited, the duration is short, and the problem of refractory blocking of high-wax oil wells cannot be effectively solved. Aiming at the defects existing in the prior art, the development of an efficient paraffin removal and blocking remover based on a multiple synergistic mechanism is urgently needed. The ideal novel blocking remover has the comprehensive functions of rapid permeation, high-efficiency dissolution, stable dispersion and long-acting inhibition, and can adapt to severe working conditions of oil fields. Particularly, the limitation of the traditional single dissolution mechanism needs to be broken through, and the blocking remover component can break the paraffin crystal structure, permeate into the sediment and be broken down and dispersed into fine particles through innovative molecular structure design so as to prevent the fine particles from being reaggregated and deposited. Meanwhile, the blocking remover also has good environmental adaptability and economy, and can be widely applied to oil wells with different geological conditions. Under the background, the two modified compounds with brand new structures are designed and synthesized, a complete blocking remover formula system and a preparation process are constructed, and a new technical scheme is provided for solving the problem of paraffin blocking of the high-wax-content oil well. Disclosure of Invention Aiming at the defects of the prior art, the invention aims to provide a high-efficiency paraffin removal and blocking remover for a high-paraffin-content oil well and a preparation method thereof. The invention provides a preparation method of a high-efficiency paraffin removal and blocking remover for a high-paraffin-content oil well, which comprises the following steps: S1, adding kerosene, dimethylbenzene and n-butanol into a reaction kettle at room temperature, and stirring