CN-122010467-A - High-temperature-resistant large-temperature-difference cement paste for oilfield cementing and application thereof

Abstract

The invention relates to high-temperature-resistant large-temperature-difference cement paste for oilfield cementing and application thereof, in particular to the technical field of petroleum drilling. According to the cement paste provided by the invention, the cement paste can resist ultrahigh temperature and large temperature difference when being used for cementing, so that the cementing operation of an ultra-deep well is realized, and the oil well development effect is ensured by utilizing the synergistic cooperation of the specific fluid loss agent and the retarder in the cement paste system.

Inventors

• SUN BAOYU
• YAN WEIJUN
• GAO WENLONG
• DU FU
• WEI JIJUN
• WANG XIAOLIANG
• ZHAO LIANG
• YAN CHANG
• ZHANG LI
• Luo xinhu
• MA ZHIHE
• QIN YAO
• XIA BOYI
• XIAO SHIJIE
• ZHANG TIEMING
• LUO KAI

Assignees

• 中国石油集团长城钻探工程有限公司
• 中国石油天然气集团有限公司

Dates

Publication Date

20260512

Application Date

20241111

Claims (10)

1. 1. A high temperature and large temperature differential resistant cement slurry for oilfield cementing, comprising: Cement for well cementation, reinforcing admixture, AMPS/AM/AA terpolymer fluid loss agent, defoamer, retarder GWR-300L, stabilizer and water.
2. 2. The cement slurry of claim 1, wherein the cement slurry comprises, in parts by weight: 400-600 parts of well cementation cement, 250-350 parts of reinforcing admixture, 55-81 parts of AMPS/AM/AA terpolymer fluid loss agent, 1.5-2 parts of defoamer, 32-48 parts of retarder GWR-300L, 0.1-0.2 part of stabilizer and 270-400 parts of water.
3. 3. The cement slurry of claim 1, wherein the well cement comprises a class G well cement.
4. 4. The cement slurry of claim 1, wherein the reinforcing admixture comprises quartz sand having a particle size of 200-350 mesh.
5. 5. The cement slurry of claim 1, wherein the AMPS/AM/AA terpolymer fluid loss additive comprises fluid loss additive GWF-200L.
6. 6. The cement slurry of claim 1, wherein the defoamer comprises a defoamer GWX-1L or tributyl phosphate.
7. 7. The cement slurry of claim 1, wherein the stabilizing agent comprises one or a combination of at least two of welan gum, xanthan gum, or biogel.
8. 8. A method according to claim 1, wherein the cementing operation is performed by using the cement slurry.
9. 9. The use according to claim 8, wherein the working temperature of the well cementation is not less than 220 ℃.
10. 10. The use according to claim 8, wherein the working temperature difference of the well cementation is not less than 80 ℃.

Description

High-temperature-resistant large-temperature-difference cement paste for oilfield cementing and application thereof Technical Field The invention relates to the technical field of petroleum drilling, in particular to high-temperature-resistant large-temperature-difference cement paste for oilfield well cementation and application thereof. Background At present, deep ultra-deep oil gas becomes a domestic particularly important alternative energy source, and ultra-deep wells are more and more. The quality of the shaft is directly related to success and failure of drilling engineering and the service life of an oil gas well, well cementation is a key technology for guaranteeing the quality of the well engineering, cement slurry is a key technology for well cementation, and the method is an important means for guaranteeing sustainable and high-quality development of oil gas field exploration and development. Due to the complex problems of geological conditions, pressure systems, temperature systems, well depth structures and the like existing in ultra-deep wells, the long-term packing quality must be ensured. Especially, the safety density window is narrow, the quality qualification rate of well cementation is low under the coexistence condition that the difficulty of primary upward return of well cementation and continuous filling of cement is high and low, and the cement slurry performance needs to be further improved. In recent years, polymer high temperature difference resistant well cementation additive is fastest in development, such as common LW-1, FC-03, SK-1, TD-X, TD-S, J-2B, T121, T-50A, W and other products, and as CN115304302A discloses a well cementation cement admixture suitable for CO2-EGS and a preparation method thereof, and relates to the technical field of oil and gas field development well cementation materials. CN107902933a discloses a high Wen Cuitui external admixture for oil well cement and a preparation method thereof, which solves the problem that a cement slurry system in the prior art is not suitable for cementing a geothermal well in the presence of ultra-high temperature and ultra-large temperature difference, and the external admixture comprises 40% -60% of photovoltaic silicon, 15% -30% of fumed silica, 15% -30% of re-burned magnesia and 1% -2% of mineral fibers. Although many of the additives are practically applied to oil field well cementation and achieve good effects, the additives can only be used below 200 ℃, and the temperature difference between the circulation temperature and the resting temperature is within 50 ℃, namely the existing cement slurry system for the ultra-deep well still has the defect of intolerance to high temperature and large temperature difference, and on the basis of the defects, the improvement of the cementing additives and the cement stones resistant to large temperature difference is needed to further improve the temperature resistance. Disclosure of Invention In view of the problems existing in the prior art, the invention aims to provide high-temperature-resistant large-temperature-difference cement paste for oilfield cementing and application thereof, so as to solve the defect that the current cement paste system for ultra-deep wells still has temperature-difference resistance. To achieve the purpose, the invention adopts the following technical scheme: in a first aspect, the invention provides a high temperature and large temperature difference resistant cement slurry for oilfield cementing, comprising: Cement for well cementation, reinforcing admixture, AMPS/AM/AA terpolymer fluid loss agent, defoamer, retarder GWR-300L, stabilizer and water. According to the cement paste provided by the invention, through the synergistic cooperation of the specific fluid loss agent and the retarder in the cement paste system, the obtained cement paste can resist ultrahigh temperature (more than or equal to 220 ℃) and large temperature difference (more than or equal to 80 ℃) when being used for cementing, so that the cementing operation of an ultra-deep well is realized, and the development effect of an oil well is ensured. As a preferred technical scheme of the invention, the cement slurry comprises the following components in parts by weight: 400-600 parts of well cementation cement, 250-350 parts of reinforcing admixture, 55-81 parts of AMPS/AM/AA terpolymer fluid loss agent, 1.5-2 parts of defoamer, 32-48 parts of retarder GWR-300L, 0.1-0.2 part of stabilizer and 270-400 parts of water. As a preferred technical solution of the present invention, the well cementing cement comprises a G-grade well cementing cement. As a preferred technical scheme of the invention, the reinforced admixture comprises quartz sand with the granularity of 200-350 meshes. As a preferable technical scheme of the invention, the AMPS/AM/AA terpolymer fluid loss agent comprises a fluid loss agent GWF-200L. As a preferred technical scheme of the invention, the defoaming agent compris