Gels
·
2024
·Vol. 10
·期 1
·73
·
IF 5
Quanyang Wang,Jing Cai,Jiannan Wang,Chenghua Zhou,Xinxin Wen,Jiang Zhang,Hui Mao
With the gradual deepening of the exploration and development of deep and ultra-deep oil and gas resources, the problem of lost circulation in drilling operations is becoming more and more complex. From field experience, conventional plugging materials cannot fully meet the technical requirements of plugging operations in drilling engineering. In this study, a high-temperature- and salt-resistant polymer HDZ−A was synthesized. A high-temperature and delayed crosslinking polymer gel plugging agent can be prepared by adding a certain concentration of a crosslinking agent and a retarder. In this paper, the optimum synthesis conditions of the HDZ−A were determined with orthogonal experiments using viscoelasticity and viscosity as evaluation criteria for newly developed polymers. The molecular structure, temperature resistance, and relative molecular mass of HDZ−A were determined using infrared spectroscopy, nuclear magnetic resonance spectroscopy, and gel permeation chromatography. In addition, the optimal formula of the gel plugging agent was determined using gel strength as the evaluation standard. The results show that the newly developed gel plugging agent has stable performance after high-temperature crosslinking, and can resist high temperatures of 160 °C during formation. Under conditions of 160 °C, the gelation time can reach 4.5 h, and the plugging efficiency can reach more than 97%. Finally, the field test of the newly developed high-temperature-resistant delayed crosslinking polymer gel plugging agent was carried out in the direct exploration well KT-14X in the Ordos Basin. The field test showed that the plugging effect of the HDZ−A gel plugging agent was remarkable.
研究领域:
石油工程
·
高分子化学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF POLYMERS AND THE ENVIRONMENT
·
2024
·
IF 4.7
Chen Jindong,Qiu Hengbin,Djouonkep Lesly Dasilva Wandji,Lv Junxian,Xie Binqiang
Addressing the complex issue of lost circulation in drilling operations is crucial as it increases nonproductive time and costs. Conventional gel plugging materials often exhibit low temperature resistance, poor pumpability, and low pressure-bearing capacity. To overcome the limitations, a self-made polymer (HSA) was initially synthesized and mixed with two crosslinker agents (MBA/PEI) at room temperature to induce a new type of high-temperature-resistant and pressure-resistant polymer gel agent (HSA-G). Investigating the gel strength and plugging capacity, the vertical inverted tube observation, 71-type high-temperature and high-pressure (HTHP) instruments, and high-pressure filter with varying fracture cracks (3–5 mm) were employed. HSA-G demonstrated excellent gelation strength for 4–5 h at 140 °C, while retaining more than 57% of its gel strength after aging at 140 °C for 144 h, which is 3 times higher than the commercially available hydrolyzed polyacrylamide (HPAM + PEI). The excellent performance was attributed to the synergy between PEI-MBA, which induces tight-crosslinked interconnected structure within HSA-G, mitigating fluid losses to only 72 mL compared to 194 mL for HPAM-G, under 8.5 MPa in the HTHP sand bed at 140 °C. In the fracture leakage simulations using a 5 mm crack performed at 6 MPa at room temperature, the filtration loss of HSA-G is 300 mL, almost half that of HPAM-G, showcasing its superior plugging and high-pressure bearing performance. In conclusion, HSA-G has not only demonstrated operational effectiveness in reducing downtime costs and fluid losses but can also temporally replace cement plugging to prevent reservoir contamination in alignment with environmentally friendly practices.
研究领域:
石油工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2020
·
IF 5.065
Binqiang Xie,Jiang Ma,Yun Wang,Alain P. Tchameni,Mingwang Luo,Jiantai Wen
Cross-linked polymer gels have attracted a strong interest for lost circulation treatment in drilling operation. However, the application of gels in high temperature loss zone was still limited due to the problems of short gelation time, weak strength, poor thermal stability, etc. In this paper, a novel cross-linked modified polyacrylamide gel (HMP-Gel), which consisted of a hydrophobically modified polyacrylamide (HMP) and crosslinker polyethyleneimine (PEI), was designed and developed. The novel HMP was synthesized to form and strengthen the gel structure due to the crosslinkable amide groups and associable hydrophobic moieties, and PEI was used to extend gelation time at high temperature. In detail, the HMP of acrylamide (AM), octadecyl acrylate (OA), and 2-acrylamide-2-methylpropanesulfonic acid (AMPS) was prepared using micellar copolymerization under the best conditions. The molecular structure of HMP was characterized using FT-IR, gel permeation chromatography and environmental scanning electron microscope (ESEM). In gelation process, effects of PEI concentration, HMP concentration, temperature and salinity on gel performance (plugging efficiency and gelation time) were systematically investigated. Plugging performance of HMP-Gel was studied using both the HTHP carbonate bed filtration loss test and HTHP crack plugging test. Rheological property of HMP-Gel was studied to access the elastic properties and gel strength. Results of various factors on gel performance indicated that HMP-Gel showed the good plugging efficiency for carbonate bed and controllable gelation time in the temperature range of 100–150 °C. Results from plugging tests indicated that the HMP-Gel had better sealing ability than HPAM-gel for both the high permeable carbonate bed and 1-3 mm cracks loss zone. And the breaking pressure of HMP-Gel could reach 1000 psi and 600 psi for carbonate bed and 3 mm slot, respectively. Additionally, HMP-Gel also showed high elasticity, gel strength, and excellent thermal stability at 140 °C. Finally, the micro-morphology of gel was further analyzed through ESEM. A new strategy of using hydrophobically modified polyacrylamide to strengthen the gel structure was proposed, and extensive laboratory tests suggested that HMP-Gel could be considered as an efficient plugging material and showed great potential in applications for lost circulation in high-temperature well.
研究领域:
石油工程
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
Geoenergy Science and Engineering
·
2025
·
IF 4.6
Yingrui Bai,Youming Lang,Ping Wang,Ren Wang,Yang Bai,Jinsheng Sun
Lost circulation in fractured formations is a worldwide problem experienced in drilling engineering characterized by low plugging efficiency and poor plugging effect. Adhesive materials are introduced to solve the problems of poor self-adaptation of the conventional composite bridging plugging systems in fractured formations and repeated lost circulation caused by pressure fluctuations. As a thermoplastic resin with low price and good chemical stability, aging resistance and adhesive properties, ethylene vinyl acetate (EVA) can be filling and adhesion in the form of particles in fracture channels. Therefore, this study evaluated the viscoelasticity, high-temperature stability and glass transition characteristics of EVA particles as well as quantitatively analyzed the degree of melting of EVA based on visualization, thermogravimetric, dynamic thermodynamic and particle size analysis experiments. The optimal formulation of the bridging system with adhesive material was optimized through fracture pressure-bearing plugging experiments and the mechanism of action of the system was revealed. The experimental results reveal that the adhesive EVA particles have good thermal stability (thermally decomposes after 374 °C) and viscoelasticity. A simulation experiment involving plugging a 2-mm fracture using the bridging system with adhesive material reveals that the pressure-bearing capacity is 12 MPa, the cumulative filtration loss is only 50 mL, and the plugging performance is excellent. We inferred that the surface of the adhesive material softened at a specific temperature and possessed strong viscoelasticity, which strengthened the bridging, filling, and twisting of the conventional composite bridging plugging system and increased coherence with the fracture channel surface and increased its stationary capacity. The plugging is synergistic, the plugging zone is strengthened, and the success rate of primary plugging is improved.
研究领域:
石油工程
·
材料科学
✓ 已验证
DOI
高影响因子
Polymers
·
2025
·Vol. 17
·期 17
·2397
·
IF 4.9
Zhilei Zhang,Yuan Geng,Ren Wang,Zhiyuan Yan,Minghao Sun,Sicong Meng,Yan Zhang,Hong Yang,Yaoxuan Li,Yuecheng Zhu
To address the issues of traditional gels in high-temperature reservoir leakage plugging, such as injection–retention imbalance, poor high-temperature stability, and insufficient thixotropy, this study developed a thixotropic polymer gel system via molecular design and component optimization, aiming to achieve excellent thixotropy, high strength, and wide temperature adaptability (80–140 °C) while clarifying its gelation mechanism. First, the optimal polymer was selected by comparing the high-temperature stability and crosslinking activity of AM/AMPS copolymer (J-2), low-molecular-weight acrylamide polymers (J-3, J-4), and AM/AMPS/NVP terpolymer (J-1). Then, the phenolic crosslinking system was optimized: hexamethylenetetramine (HMTA) was chosen for controlled aldehyde release (avoiding poor stability/dehydration) and catechol for high crosslinking efficiency (enhancing strength via dense crosslinking sites). Urea–formaldehyde resin (UF) was introduced to form a “polymer-resin double network,” improving high-temperature compression resistance and long-term stability. Cyclic shear rheological tests showed the gel system had a larger hysteresis area than the polymer solution, indicating excellent thixotropy before gelation. It gelled completely at 80–140 °C (gelation time shortened with temperature). At 120 °C, its viscosity was 7500 mPa·s, storage modulus (G′) 51 Pa, and loss modulus (G″) 6 Pa, demonstrating good shear thixotropy. The final system (1% J-1, 0.3% catechol, 0.6% HMTA, 15% UF) is suitable for high-temperature reservoir leakage plugging.
研究领域:
高分子科学
·
石油工程
·
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Polymers
·
2025
·Vol. 17
·期 15
·1999
·
IF 4.9
Wenzhe Li,Pingya Luo,Xudong Wang
Lost circulation is a major challenge in oil and gas drilling operations, severely restricting drilling efficiency and compromising operational safety. Conventional bridging and plugging materials rely on precise particle-to-fracture size matching, resulting in low success rates. Self-healing gels penetrate loss zones as discrete particles that progressively swell, accumulate, and self-repair in integrated gel masses to effectively seal fracture networks. Self-healing gels effectively overcome the shortcomings of traditional bridging agents including poor adaptability to fractures, uncontrollable gel formation of conventional downhole crosslinking gels, and the low strength of conventional pre-crosslinked gels. This work employs stearyl methacrylate (SMA) as a hydrophobic monomer, acrylamide (AM) and acrylic acid (AA) as hydrophilic monomers, and graphene oxide (GO) as an inorganic dopant to develop a GO-based self-healing organic–inorganic hybrid plugging material (SG gel). The results demonstrate that the incorporation of GO significantly enhances the material’s mechanical and rheological properties, with the SG-1.5 gel exhibiting a rheological strength of 3750 Pa and a tensile fracture stress of 27.1 kPa. GO enhances the crosslinking density of the gel network through physical crosslinking interactions, thereby improving thermal stability and reducing the swelling ratio of the gel. Under conditions of 120 °C and 6 MPa, SG-1.5 gel demonstrated a fluid loss volume of only 34.6 mL in 60–80-mesh sand bed tests. This gel achieves self-healing within fractures through dynamic hydrophobic associations and GO-enabled physical crosslinking interactions, forming a compact plugging layer. It provides an efficient solution for lost circulation control in drilling fluids.
研究领域:
石油工程
·
材料科学
·
化学工程
·
地质学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Gels
·
2025
·Vol. 11
·期 8
·578
·
IF 5.3
Yancheng Yan,Tao Tang,Biao Ou,Jianzhong Wu,Yuan Liu,Jingbin Yang
In petroleum exploration and production, lost circulation not only significantly increases exploration and development costs and operational cycles but may also lead to major incidents such as wellbore instability or even project abandonment. This paper constructs a polymer gel plugging system by optimizing high-molecular-weight polymers, crosslinker systems, and resin hardeners. The optimized system composition was determined as 1% polymer J-1, 0.3% catechol, 0.6% hexamethylenetetramine (HMTA), and 15% urea–formaldehyde resin. Experimental studies demonstrated that during the initial stage (0–3 days) at 120 °C, the optimized gel system maintained a storage modulus (G′) of 17.5 Pa and a loss modulus (G″) of 4.3 Pa. When the aging period was extended to 9 days, G′ and G″ decreased to 16 Pa and 4 Pa, respectively. The insignificant reduction in gel strength indicates excellent thermal stability of the gel system. The gel exhibited superior self-filling capacity during migration, enabling complete filling of fractures of varying sizes. After aging for 1 day at 120 °C, the plugging capacity of the gel system under water flooding and gas flooding conditions was 166 kPa/m and 122 kPa/m, respectively. Furthermore, a complete gel barrier layer formed within a 6 mm wide vertical fracture, demonstrating a pressure-bearing capacity of 105.6 kPa. This system shows good effectiveness for wellbore isolation and fracture plugging. The polymer gel plugging system studied in this paper can simplify lost circulation treatment procedures while enhancing plugging strength, providing theoretical support and technical solutions for addressing lost circulation challenges.
研究领域:
石油工程
·
钻井液
·
高分子科学
·
油藏工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF PETROLEUM SCIENCE AND ENGINEERING
·
2022
·
IF 5.168
Lili Yang,Chunlin Xie,Tian Ao,Kaixiao Cui,Guancheng Jiang,Baojun Bai,Yongwei Zhang,Jun Yang,Xingxing Wang,Weiguo Tian
Lost circulation has been a serious problem to be solved in many drilling practices during oil, gas and geothermal well drillings. Many materials have been developed and evaluated for the purpose. However, their performance to plug severe leakoff is very limited. Herein, an injectable self-healing hydrogel based on polyampholyte with sulfonated and quaternary ammonium functionalities (P(MPTC- co -NaSS)) was developed and comprehensively evaluated to prevent the severe loss of fluids to formation. By incorporating cation-π (π is for aromatic residues) interaction, the hydrogel shown self-healing property and robustness in severe environment (temperature, salt) by comparison with other hydrogels merely consisting of cation-anion and H-bonding interactions. Aromatic residues enhanced thermal stability above 310 °C. The plugging measurement shown that an addition of 2 wt% dried gel particles can plug high-permeability formation and endure a high pressure of 6 MPa, produce much lower circulation loss and result in a dramatically increased loss volume reduction rate (63.5%) compared with a commercial polymer gel product and an inert material (9.4%) after a self-healing process. Markedly, P(MPTC- co -NaSS) can be used in a wide range of formation temperature (as high as 150 °C) and salt concentrations (NaCl, CaCl 2 , as high as 15 wt %). In addition to suitable particle size and mechanically robustness, it was also attributed to the soft, swelling, deformable, toughness and self-healable features of P(MPTC- co -NaSS) gel particles as well as the strong adhesion to negatively charged formations in water, even under high thermal and saline condition. These characteristics also contributed to a long-term plugging performance, beneficial to avoid repeated lost circulation in drilling operation. Besides, this self-healing polyampholyte gel particles dispersed well in saline fluid and maintained stable rheological properties after hot rolling, which was favorable to drilling fluid circulation. This study shown the application potential of self-healing materials as plugging material candidate in petroleum drilling industry.
研究领域:
石油工程
·
钻井技术
·
功能高分子材料
·
流体损失控制
·
油田化学
✓ 已验证
DOI
高影响因子
Petroleum Science
·
2025
·
IF 6.1
Li-Yao Dai,Jin-Sheng Sun,Kai-He Lv,Ying-Rui Bai,Bo Liao,Dong-Qing Yang,Chao-Zheng Liu,Mei-Chun Li
Fractures in geological formations, which are commonly encountered during oil and gas exploration, pose significant challenges by facilitating fluid loss and reducing wellbore stability. Polymer gels hold significant promise as lost circulation materials due to their excellent deformability under pressure and self-adaptability. However, conventional gels face certain limitations, such as poor retention of gel-forming suspensions in fractures, low structural strength, and instability at high temperatures. These issues result in low pressure-bearing capacity and, consequently, reduced effectiveness in sealing formation fractures. This study presents the synthesis of a supramolecular polymer gel (SPG) composed of acrylamide (AM), 2-acrylamide-2-methylpropanesulfonic acid (AMPS), divinylbenzene (DVB), polyvinyl alcohol (PVA), TEMPO-oxidized cellulose nanofibers (CNFs), and laponite via in situ radical polymerization. Due to the synergistic effects of hydrogen bonding and electrostatic interactions, the supramolecular polymer gel-forming suspension exhibits high retention capacity in fractures. The as-synthesized gels demonstrate remarkable temperature resistance and high mechanical strength, attributed to covalent bonding, multiple hydrogen bonding, and electrostatic interactions, along with the high aspect ratio and modulus of CNFs and laponite. This study broadens the application scope of CNFs, laponite, and SPGs, offering a novel approach for the efficient development of unconventional oil and gas resources.
研究领域:
材料科学
·
石油工程
·
高分子化学
·
纳米复合材料
·
油田化学
✓ 已验证
产品关联
DOI
高影响因子
ENERGY & FUELS
·
2025
·
IF 5.3
Lixin Zhu,Weian Huang,Jia He,Ting Yu,Xushuo Zhang,Jianghong Jia,Shuangjun Zhou
The development of effective lost circulation control materials for complex karst formations remains a critical challenge in deep and unconventional reservoir drilling. This study presents a water-responsive polymer synthesized through inverse emulsion copolymerization using hydrophilic monomers (acrylamide, acrylic acid, and 2-acrylamido-2-methylpropanesulfonic acid) and hydrophobic monomers (octadecyl acrylate). Advanced characterization techniques, including Fourier Transform Infrared Spectroscopy (FTIR), Gel Permeation Chromatography (GPC), Dynamic Light Scattering (DLS), Thermal Gravimetric Analysis (TGA), and Scanning Electron Microscopy (SEM), revealed a water-triggered structural transformation from irregular morphologies to three-dimensional cocontinuous networks. This transformation is driven by hydrogen bonding and van der Waals interactions, which facilitate the formation of supramolecular architecture through intermolecular hydrophobic associations. The polymer emulsion demonstrates exceptional thickening performance, maintaining high apparent viscosity in both distilled water (2150 mPa·s at 2 wt %) and saline conditions (1680 mPa·s at 2 wt %). It also exhibits favorable shear-thinning and static-thickening behavior, with dynamic viscosity reducing from 5140 mPa·s to 280 mPa·s at 200 s–1 (at 5 wt %). Prolonged water exposure enhances the sealing efficacy, achieving 10% linear expansion after 48 h. Additionally, thermal stability testing at 140 °C for 16 h demonstrates that the sealing integrity is maintained in sand beds. Integrated with optimized conventional materials, the composite plugging system effectively seals 3 mm-wide fractures under 8 MPa. Molecular dynamics simulations confirm the adsorption mechanisms and surface retention behavior that govern the fracture sealing. This salt-tolerant, thermally stable polymer emulsion system overcomes conventional retention limitations in karst formations, enabling efficient one-time plugging with industrial scalability. This work establishes a new paradigm for the development of stimuli-responsive materials to control complex downhole fluid losses.
研究领域:
高分子科学
·
石油工程
·
材料科学
·
胶体与界面科学
·
超分子化学
·
地质工程
✓ 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）