Gels
·
2023
·Vol. 9
·期 12
·966
·
IF 4.6
Yinbo He,Mingliang Du,Jing He,Haiyang Liu,Yanhua Lv,Lei Guo,Peng Zhang,Yunhai Bai
Oil-based drilling fluids are widely used in challenging wells such as those with large displacements, deepwater and ultra-deepwater wells, deep wells, and ultra-deep wells due to their excellent temperature resistance, inhibition properties, and lubrication. However, there is a challenging issue of rheological deterioration of drilling fluids under high-temperature conditions. In this study, a dual-amphiphilic segmented high-temperature-resistant gelling agent (HTR-GA) was synthesized using poly fatty acids and polyether amines as raw materials. Experimental results showed that the initial decomposition temperature of HTR-GA was 374 °C, indicating good thermal stability. After adding HTR-GA, the emulsion coalescence voltage increased for emulsions with different oil-to-water ratios. HTR-GA could construct a weak gel structure in oil-based drilling fluids, significantly enhancing the shear-thinning and thixotropic properties of oil-based drilling fluids under high-temperature conditions. Using HTR-GA as the core, a set of oil-based drilling fluid systems with good rheological properties, a density of 2.2 g/cm3, and temperature resistance up to 220 °C were constructed. After aging for 24 h at 220 °C, the dynamic shear force exceeded 10 Pa, and G′ exceeded 7 Pa, while after aging for 96 h at 220 °C, the dynamic shear force exceeded 4 Pa, and G″ reached 7 Pa. The synthesized compound HTR-GA has been empirically validated to significantly augment the rheological properties of oil-based drilling fluids, particularly under high-temperature conditions, showcasing impressive thermal stability with a resistance threshold of up to 220 °C. This notable enhancement provides critical technical reinforcement for progressive exploration endeavors in deep and ultra-deep well formations, specifically employing oil-based drilling fluids.Keywords:gelling agent;oil-based drilling fluid;weak gel;high-temperature resistance
研究领域:
石油工程
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Gels
·
2023
·Vol. 9
·期 9
·729
·
IF 4.6
Haokun Shen,Jinsheng Sun,Kaihe Lv,Meichun Li,Yuan Geng,Zheng Yang,Xianbin Huang,Hongyan Du,Muhammad Arqam Khan
Drilling cuttings from the rock formation generated during the drilling process are generally smashed to fine particles through hydraulic cutting and grinding using a drilling tool, and then are mixed with the drilling fluid during circulation. However, some of these particles are too small and light to be effectively removed from the drilling fluid via solids-control equipment. These small and light solids are referred to as low gravity solids (LGSs). This work aimed to investigate the effect of LGSs on the performance of oil-based drilling fluid (OBDF), such as the rheological properties, high-temperature and high-pressure filtration loss, emulsion stability, and filter cake quality. The results show that when the content of LGSs reached or even exceeded the solid capacity limit of the OBDF, the rheological parameters including the plastic viscosity, gel strength, and thixotropy of OBDF increased significantly. Furthermore, the filtration of OBDF increases, the filter cake becomes thicker, the friction resistance becomes larger, and the stability of emulsion of OBDF also decreases significantly when the concentration of LGSs reached the solid capacity limit of OBDF (6–9 wt% commonly). It was also found that LGSs with a smaller particle size had a more pronounced negative impact on the drilling fluid performance. This work provides guidance for understanding the impact mechanism of LGSs on drilling fluid performance and regulating the performance of OBDF.Keywords:low gravity solids;oil-based drilling fluid;weak gel structure;rheology
研究领域:
石油工程
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MOLECULES
·
2023
·Vol. 28
·期 7
·3125
·
IF 4.6
Jiqiang Zhi,Yikun Liu,Jinfeng Chen,Lifeng Bo,Guohui Qu,Nan Jiang,Weizhong He
We targeted high-temperature and highly saline old oil fields, whose environmental conditions could be attributed to the significantly high heterogeneity cause by long-term water flooding. The Huabei Oilfield was chosen as the research object. We developed a hydrophobic functional monomer–polymer with temperature and salt resistance by introducing the temperature-resistant and salt-resistant monomer NVP and a hydrophobic functional monomer into the main chain for copolymerization. We used a crosslinking agent with phenolic resin to prepare a weak gel system that showed temperature and salt resistance and investigated its temperature and salt resistance, infective property, plugging performance, liquid flow ability, micropore throat migration, and plugging characteristics. The results obtained using the infrared spectroscopy technique revealed the successful preparation of the phenolic resin crosslinker. The weak gel exhibited good temperature and salt resistance when the polymer concentration was 2000 mg/L, the cohesion ratio was 1:1.5, the additive concentration was 2000 mg/L, the reservoir temperature was 120 °C, and the injected water salinity was 40,300.86 mg/L. The average viscosity retention rate of the 90-day weak gel reached more than 80% and its microstructure was examined. The coreflow experiment results revealed that the weak gel system was characterized by good infectivity. After plugging the weak gel, the effect on the direction of the liquid flow was evident and the flow rate of the low permeability layer increased to a maximum of 48.63% under conditions of varying permeability levels. A significant improvement in the water absorption profile was achieved. The plugging was carried out through a sand-filling pipe under varying permeability conditions and the pressure measuring points in the sand-filling pipe were sucessfully pressurized. The migration ability of the weak gel was good and the blocking rate was >85%.Keywords:temperature and salt tolerance;weak gel preparation;profile control;fluid flow direction;plugging performance
研究领域:
石油工程
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Gels
·
2022
·Vol. 8
·期 10
·631
·
IF 4.432
Xianbin Huang,Xu Meng,Mao Li,Jinsheng Sun,Kaihe Lv,Chongyang Gao
Oil-based drilling fluids (OBDFs) are widely used, but there are common problems associated with them, such as low yield point and poor cutting–carrying and hole cleaning ability. In this paper, a polyamide wax (TQ-1) was synthesized from dimeric acid and 1,6-hexanediamine to improve the weak gel structure of OBDFs. The TQ-1 was characterized by Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). Then the effect of the TQ-1 on the stability of the water-in-oil emulsion was studied by sedimentation observation, stability analysis, an electrical stability test, and particle size measurement. The effect of the TQ-1 on the rheological properties of the water-in-oil emulsion was analyzed by viscosity vs. shear rate test and the three-interval thixotropic test. Finally, the performance of the TQ-1 in OBDFs was comprehensively evaluated. The experimental results showed that the initial thermal decomposition temperature of the TQ-1 was 195 °C, indicating that the TQ-1 had good thermal stability. After adding the TQ-1, the emulsion became more stable since the emulsion stability index (TSI) value decreased when the emulsions were placed for a period of time and the demulsification voltage was increased. The TQ-1 could form a weak gel structure in the water-in-oil emulsions, which made the emulsions show excellent shear thinning and thixotropy. TQ-1 can improve the demulsification voltage of OBDFs, greatly improve the yield point and gel strength, and largely reduce the sedimentation factor (SF). In addition, TQ-1 has good compatibility with OBDFs, and in our study the high-temperature and high-pressure (HTHP) filtration decreased slightly after adding the TQ-1. According to theoretical analysis, the mechanism of TQ-1 of improving the weak gel structure of OBDFs is that the polar amide group can form a spatial network structure in nonpolar solvents through hydrogen bonding.
研究领域:
石油工程
·
材料科学
✓ 已验证
DOI
高影响因子
CHEMISTRY AND TECHNOLOGY OF FUELS AND OILS
·
2023
·Vol. 59
·期 1
·192-201
·
IF 0.6
Tang Yajuan,Wang Hongmei,Gao Shanshan,Han Dan,Du Jinxiu,Wang Rui,Liu Yikun,Qu Guohui
The use of highly mineralized reinjection water has low gel strength and poor stability, and the above problems are more prominent under high-temperature reservoir conditions. Based on the temperature resistance and salt tolerance polymer TSRP and phenolic resin crosslinking agent, a TSRP temperature resistant weak gel system suitable for high mineralized reinjection water was developed, and the temperature resistance mechanism of the TSRP weak gel system was tested by its temperature resistance and injection ability. The migration, retention, and plugging of the TSRP weak gel system in heterogeneous reservoirs were studied through micropore throat migration and plugging characteristics and dual-pipe parallel oil displacement experiments. The results showed that: under the condition of polymer concentration 2000 mg/L, polymer: crosslinking agent: glue promoter 1:1.5:1, the TSRP weak gel system prepared by using mineralized 12132.9 mg/L reinjection water can remain stable after 95°C aging at high temperature of TSRP. Through microscopic simulation, a glass etching model TSRP weak gel system showed good migration ability and plugging performance. In comparison with the two pipes parallel oil displacement experiment, the KY gel system injected the same amount of PV at 95°C and 20000 mg/L in the Y1L block, the average recovery of the TSRP gel system increased by 22.3% after injection of polymer gel, and the KY gel system was only 18.2%; When the same amount of PV was injected in Z1L block, 95°C and 22000 mg/L, the average recovery of TSRP gel system increased by 24.35% after injection of polymer gel, and the KY gel system was only 17.15%, that is, under higher salinity, the TSRP gel system showed better performance.
研究领域:
石油工程
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）