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CN-122012055-A - Well cementation flushing fluid for oil-based drilling fluid and preparation method and application thereof

CN122012055ACN 122012055 ACN122012055 ACN 122012055ACN-122012055-A

Abstract

The invention belongs to the technical field of petroleum exploitation, and particularly relates to a well cementation flushing fluid for oil-based drilling fluid, and a preparation method and application thereof. The well cementation flushing fluid for the oil-based drilling fluid comprises, by weight, 18-25 parts of a cosolvent, 15-20 parts of mineral oil, 5-10 parts of a nonionic emulsifier, 10-15 parts of an anionic emulsifier, 2-4 parts of a penetrating agent, 2-5 parts of an inorganic salt, 0.5-1 part of a defoaming agent and the balance of water, wherein the total weight of the raw materials is 100. The well cementation flushing fluid system for the oil-based drilling fluid has good rheological property, high stability, good flushing effect and good compatibility with the drilling fluid and the cement slurry system, does not have thickening phenomenon after mixing, does not pollute the well cementation fluid, and ensures the requirements of high-quality well cementation construction.

Inventors

  • Qi ben
  • YU QIANQIAN
  • MA RURAN
  • WANG QIKE
  • LIU WENMING
  • WU CHAOMING
  • Luo Likui
  • ZONG YONG
  • CHEN XU
  • HE GUANXI

Assignees

  • 中国石油集团渤海钻探工程有限公司
  • 中国石油天然气集团有限公司

Dates

Publication Date
20260512
Application Date
20241111

Claims (10)

  1. 1. The well cementation flushing fluid for the oil-based drilling fluid is characterized by comprising, by weight, 18-25 parts of a cosolvent, 15-20 parts of mineral oil, 5-10 parts of a nonionic emulsifier, 10-15 parts of an anionic emulsifier, 2-4 parts of a penetrating agent, 2-5 parts of inorganic salt, 0.5-1 part of a defoaming agent and the balance of water, wherein the total weight of the raw materials is 100.
  2. 2. The well cementing rinse for oil-based drilling fluids of claim 1, wherein the co-solvent comprises one or more of ethylene glycol butyl ether, diethylene glycol butyl ether, n-butanol, and n-pentanol.
  3. 3. The well cementation flushing fluid for the oil-based drilling fluid according to claim 2, wherein the cosolvent is a mixed solution of ethylene glycol butyl ether and n-amyl alcohol, and the mass ratio of the ethylene glycol butyl ether to the n-amyl alcohol is 1 (0.5-1).
  4. 4. The well cementation flushing fluid for oil-based drilling fluids according to any one of claims 1 to 3, wherein the mineral oil is a mixture of limonene and terpinolene, and the mass ratio of limonene to terpinolene is 1 (0.8 to 1.5).
  5. 5. The well cementation flushing fluid for the oil-based drilling fluid, which is characterized in that the nonionic emulsifier is a mixture of octyl phenol polyoxyethylene ether and lauryl phosphate MAE, wherein the mass ratio of the octyl phenol polyoxyethylene ether to the lauryl phosphate MAE is 1 (0.3-0.5); and/or the anionic emulsifier is a mixture of AES and sodium dodecyl sulfate, wherein the mass ratio of the AES to the sodium dodecyl sulfate is 1 (0.5-1).
  6. 6. The well cementation flushing fluid for oil-based drilling fluid according to claim 1, wherein the penetrating agent is a mixture of JFC-2 and a rapid penetrating agent T, and the mass ratio of JFC-2 to rapid penetrating agent T is 1 (0.5-1).
  7. 7. The well cementation flushing fluid for oil-based drilling fluid according to claim 5 or 6, wherein the inorganic salt is a mixture of potassium chloride and sodium tripolyphosphate, and the mass ratio of the potassium chloride to the sodium tripolyphosphate is 1 (0.1-0.2); And/or, the defoamer is a mixture of tributyl phosphate and organosilane.
  8. 8. A method of preparing a well cementing rinse for oil-based drilling fluids according to any one of claims 1 to 7, comprising the steps of: S1, dissolving a nonionic emulsifier in 50-55 ℃ water, and stirring at a low speed until the nonionic emulsifier is completely dissolved to form a solution A; S2, adding an anionic emulsifier into the solution A, and continuously stirring for a period of time at a low speed after uniformly stirring to form a solution B; S3, sequentially adding the penetrating agent, the cosolvent and the mineral oil into the solution B, and fully and uniformly stirring to form a solution C; and S4, finally adding inorganic salt and a defoaming agent into the solution C, fully and uniformly stirring, and cooling to room temperature to obtain the well cementation flushing fluid for the oil-based drilling fluid.
  9. 9. The preparation method according to claim 8, wherein in the step S1, the low-speed stirring condition is that the stirring speed is 150-300 rpm, and the stirring time is 30-40 min; and/or in the step S2, the low-speed stirring condition is that the stirring speed is 150-300 rpm, and the stirring time is 30-40 min; and/or in the step S3, stirring time is 30-40 min.
  10. 10. Use of the cementing flushing fluid for oil-based drilling fluids according to any one of claims 1 to 7 and/or the cementing flushing fluid for oil-based drilling fluids produced by the production method according to claim 8 or 9 in cementing engineering.

Description

Well cementation flushing fluid for oil-based drilling fluid and preparation method and application thereof Technical Field The invention belongs to the technical field of petroleum exploitation, and particularly relates to a well cementation flushing fluid for oil-based drilling fluid, and a preparation method and application thereof. Background With the continuous deep exploration and development, the drilling of unconventional oil and gas such as shale oil, shale gas, compact gas and the like is more and more, and the drilling of ultra-deep layers, high-pressure salt paste layers and the like is more and more frequent. Because of the stable property, the oil-based drilling fluid is used more and more in complex stratum such as shale, salt paste layer and the like and special structures such as large-displacement wells, high-temperature deep wells and ultra-deep wells and the like, and the defect of insufficient inhibitive property and lubricity of the water-based drilling fluid is overcome. The oil-based drilling fluid is used as a nonaqueous fluid system and has the advantages of low friction coefficient, high lubricity, excellent fluid loss control and good well wall stability. However, the poor compatibility of the oil-based drilling fluid and the cement slurry is an inevitable problem in the well cementation link, and the sensitivity of the cement slurry to the oil-based drilling fluid cannot be ignored. In recent years, research on well cementation technology is in progress at home and abroad, more and more researchers begin to pay attention to the influence of oil-based drilling fluid on well cementation, and the method is mainly based on how to quickly clean the oil-based drilling fluid attached to a well wall and a casing wall, so that the oil-based drilling fluid can realize the transition from an oil wetting interface to a water wetting interface, and the cementing quality of a first interface and a second interface of well cementation is further improved. Therefore, before the well cementation operation is performed, special flushing fluid is needed to be used for treatment, so that the problems of difficult well wall flushing and mutual pollution among isolating fluid, cement slurry and oil-based mud are effectively solved, and the requirement of high-quality well cementation is met. In view of this, the present invention has been made. Disclosure of Invention The invention aims to provide a well cementation flushing fluid for oil-based drilling fluid, a preparation method and application thereof, wherein the well cementation flushing fluid for oil-based drilling fluid can effectively clean diesel-based drilling fluid and white oil-based drilling fluid attached to the casing wall. Has the characteristics of good rheological property and good compatibility with drilling fluid and cement slurry. In order to overcome the defects in the prior art, the invention provides the following technical scheme: The well cementation flushing fluid for the oil-based drilling fluid comprises, by weight, 18-25 parts of a cosolvent, 15-20 parts of mineral oil, 5-10 parts of a nonionic emulsifier, 10-15 parts of an anionic emulsifier, 2-4 parts of a penetrating agent, 2-5 parts of an inorganic salt, 0.5-1 part of a defoaming agent and the balance of water, wherein the total weight of the raw materials is 100. Further, the cosolvent comprises one or more of ethylene glycol butyl ether, diethylene glycol butyl ether, n-butanol and n-pentanol. Further, the cosolvent is a mixed solution of ethylene glycol butyl ether and n-amyl alcohol, and the mass ratio of the ethylene glycol butyl ether to the n-amyl alcohol is 1 (0.5-1). Further, the mineral oil is a mixture of limonene and terpinolene, and the mass ratio of the limonene to the terpinolene is 1 (0.8-1.5). Further, the nonionic emulsifier is a mixture of octyl phenol polyoxyethylene ether and lauryl alcohol phosphate MAE, and the mass ratio of the octyl phenol polyoxyethylene ether to the lauryl alcohol phosphate MAE is 1 (0.3-0.5). And/or the anionic emulsifier is a mixture of AES and sodium dodecyl sulfate, wherein the mass ratio of the AES to the sodium dodecyl sulfate is 1 (0.5-1). Further, the penetrating agent is a mixture of JFC-2 and a rapid penetrating agent T, and the mass ratio of JFC-2 to the rapid penetrating agent T is 1 (0.5-1). Further, the inorganic salt is a mixture of potassium chloride and sodium tripolyphosphate, and the mass ratio of the potassium chloride to the sodium tripolyphosphate is 1 (0.1-0.2); And/or, the defoamer is a mixture of tributyl phosphate and organosilane. In addition, the invention also provides a preparation method of the well cementation flushing fluid for the oil-based drilling fluid, which comprises the following steps: S1, dissolving a nonionic emulsifier in 50-55 ℃ water, and stirring at a low speed until the nonionic emulsifier is completely dissolved to form a solution A; S2, adding an anionic emulsifier into the