ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2022
·Vol. 29
·期 25
·37815-37826
·
IF 5.19
Li Qiang,Wang Fuling,Forson Kobina,Zhang Jinyan,Zhang Chenglin,Chen Juan,Xu Ning,Wang Yanling
The fracturing property of liquid CO 2 fracturing fluid varies greatly due to the rheology of fracturing fluid during fracturing process. The main objective of this investigation is to study the rheology property of thickened liquid CO 2 by measuring the viscosity of thickened liquid CO 2 in different physical parameters of this prepared thickener and explain the causes of rheological changes. The results show that thickener content, branching content, and molecular weight of a thickener for all could significantly improve the rheology of liquid CO 2 ; the consistency coefficient K increased as they rose, but the rheological index n presented a decreased trend. Meanwhile, the mesh structure is proposed as a model to explain the rheological changes, and the large wetting angle means an excellent backflow, low reservoir damage, and low adsorption property. These results herein provide a basic reference to improve the CO 2 fracturing technology and molecular design of CO 2 thickener.
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
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2025
·
IF 5.4
Fangjun Jia,Haitao Li,Zimin Liu,Qi Gong,Hong wen Luo,Xin Ma,Jiating Hao,Hao Pan
This study innovatively synthesized yellow-green fluorescent sulfur-doped carbon quantum dots (S-CQDs) tracers and systematically investigates their transport and retention behaviors in sandstone reservoirs. By optimizing hydrothermal synthesis parameters, S-CQDs with uniform particle size and outstanding fluorescence properties were successfully prepared. Experimental evaluations demonstrated the stability of S-CQDs under extreme reservoir conditions, including high temperatures (up to150℃) and extreme pH values(3−10), as well as their interaction mechanisms with sandstone minerals. The findings indicate that S-CQDs tracers exhibit excellent transportability and long-term stability in sandstone formations, with their transport and retention behaviors governed by multiple factors, including particle size, concentration, flow rate, salinity, and clay mineral content. This study provides critical experimental data and theoretical insights for the application of CQDs as tracers in oil and gas reservoirs, highlighting their significant potential for subsurface fluid monitoring and hydrocarbon exploration.
研究领域:
石油工程
·
地球化学
·
纳米技术
·
环境科学
·
储层表征
✓ 已验证
产品关联
DOI
高影响因子
ChemistrySelect
·
2025
·Vol. 10
·期 27
·e04958
·
IF 2
Chen Minggui,Yan Liang
Graphical Nano-SiO₂ (0.02 wt%) extends gel stability to 95 days at 130 °C in seawater (versus 70 days control). SEM-confirmed H-bonding between Nano-SiO₂ silanols and AMPS groups reinforces network. Gelation activation energy (88.2 kJ/mol) derived via Arrhenius model. Nano-SiO₂-toughened polymer gels achieves 34.7 MPa/m breakthrough pressure (10 × base gel) in 1.4 Darcy cores. This study solves water shutoff gel syneresis/ degradation in high-salinity seawater (Ca 2 ⁺+Mg 2 ⁺ >1;500 mg/L) for South China Sea reservoirs. Reservoirs in the western South China Sea have entered a high-water-cut stage, exhibiting significant heterogeneity exacerbated by prolonged water flooding, necessitating urgent profile control measures to enhance oil recovery. Conventional polyacrylamide organic gels fail under the prevailing high-temperature (130 °C) and high-salinity conditions, characterized by divalent cation (Ca 2 ⁺ and Mg 2 ⁺) concentrations of 5650 mg/L. This study developed a robust gel profile control system specifically engineered for such challenging environments. Key parameters including polymer and crosslinker concentrations, gel pH, and temperature were systematically optimized to ensure stability under high temperature and salinity. The optimized formulation demonstrates exceptional stability in seawater at 130 °C, with a gelation activation energy of 88.2 kJ/mol. Incorporating nanosilica significantly enhanced the gel's thermal stability, salinity tolerance, and shear resistance. Scanning electron microscopy (SEM) revealed a strengthened network microstructure. The system exhibits favorable injectivity in 1.4 Darcy permeability cores. Nanosilica reinforcement dramatically increased the gel's breakthrough pressure gradient from 3.45 MPa/m to 34.7 MPa/m. Crucially, the addition of 0.02% nanosilica extended the polyacrylamide gel's functional stability from 70 days to 95 days. This nanosilica-reinforced system offers superior long-term stability and plugging performance, presenting a viable profile control and water-shutoff technology for offshore high-temperature, high-salinity seawater reservoirs.
研究领域:
石油工程
·
材料科学
·
化学工程
·
地质学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
ACS Omega
·
2024
·
IF 3.7
Kai Shan,Zhengsong Qiu,Qi Yin,Qingzhen Cui,Dandan Su,Hanyi Zhong,Xin Zhao
For the purpose of efficient temporary plugging and self-removal of the plugging of reservoir formations, the thermally induced expandable and acid-generating temporary plugging agent (TAPA) was prepared with acrylonitrile (AN), methacrylic acid (MAA), N,N-dimethylacrylamide (DMAA), and butyl acrylate (BA) as the shell monomers as well as the carboxylate esters with high boiling points as the core material. The TAPA was structurally characterized, and the properties were studied. The results showed that the TAPA had a good spherical structure with a median particle size (D50) of 16.03 μm. The initial expansion temperature Tstart of the TAPA was 134.75 °C, and its maximum expansion temperature Tmax was 197.77 °C. The surface was hydrophilic and negatively charged, with excellent shear strength and sealing. The TAPA was suitable for temporary plugging and self-removal of the plugging of the reservoir formation with a temperature of 160 °C. The release of core materials and the effect on self-removal of plugging were not significantly affected with different salinities, weak acid or weak alkali environments, or a small quantity of hydrocarbons. With addition of 1–3 wt % TAPA, the rheological property of water-based drilling fluid changed slightly, but the filtration loss reduced, suggesting a good compatibility of the TAPA with the drilling fluid. Results of plugging and plugging removal experiments in fractured reservoir formations and permeable reservoir formations showed that the TAPA improved the strength of the temporary plugging layer with the elastic deformation due to thermal expansion and realized self-removal of the plugging by corroding the temporary plugging layer with carboxylic acid hydrolyzed from the carboxylic ester released, thereby decreasing the backflow pressure of oil and gas wells in the production stage. The results provided a new method and technological idea for efficient temporary plugging and self-removal of the plugging of reservoir formations.
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
·
2024
·Vol. 29
·期 12
·2798
·
IF 4.2
Shenglong Shi,Jinsheng Sun,Shanbo Mu,Kaihe Lv,Jingping Liu,Yingrui Bai,Jintang Wang,Xianbin Huang,Jiafeng Jin,Jian Li
To investigate the effect of the chemical composition of a metal–organic crosslinker on the performances of fracturing fluid in high-temperature conditions, four zirconium (Zr) crosslinkers and one aluminum–zirconium (Al-Zr) crosslinker with a polyacrylamide were used. The crosslinkers possessed the same Zr concentration, but they differed in component amounts and the order of the addition of the crosslinker components, leading to different chemical compositions in the crosslinkers. The fracturing fluids prepared by different tested crosslinkers were compared in terms of properties of rheological behavior, sand-carrying ability, microstructure, and gel breaking characteristics. The results showed that the fracturing fluids prepared by zirconium lactic acid, ethanediamine, and sorbitol crosslinkers offered the slowest viscosity development and highest final viscosity compared to the zirconium lactic acid crosslinker and the zirconium lactic acid and ethanediamine crosslinker. The zirconium sorbitol, lactic acid, and ethanediamine crosslinker exhibited a faster crosslinking rate and a higher final viscosity than the zirconium lactic acid, ethanediamine, and sorbitol crosslinker; the crosslinker showed crosslinking density and crosslinking reactivity, resulting in more crosslinking sites and a higher strength in the fracturing fluid. The Al-Zr-based crosslinker possessed better properties in temperature and shear resistance, viscoelasticity, shear recovery, and sand-carrying ability than the Zr-based crosslinker due to the synergistic crosslinking effect of aluminum and zirconium ions. The tertiary release gelation mechanism of the Al-Zr-based fracturing fluid achieved a temperature resistance performance in the form of continuous crosslinking, avoiding the excessive crosslinking dehydration and reducing viscosity loss caused by early shear damage. These results indicated that the chemical compositions of metal–organic crosslinkers were important factors in determining the properties of fracturing fluids. Therefore, the appropriate type of crosslinker could save costs without adding the additional components required for high-temperature reservoirs.
研究领域:
石油工程
·
材料化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Omega
·
2024
·
IF 3.7
Qing Guo,Ze Li,Xuanxiang Zeng,Dan Li,Huiming An,Li Zhao,Liang Tao,Qiang Li
Reduction of the reservoir permeability during supercritical CO2 fracturing caused significant reservoir damage, which directly affects the crude oil recovery rate. This investigation explored a novel thickener for supercritical CO2 fracturing fluid, this CO2 thickener not only effectively improves the viscosity and rheological properties of CO2 fracturing fluid but also contributes to reduce reservoir damage and improve permeability. The research results indicated that the synthesized CO2 thickener (3 wt %) can increase the apparent viscosity of supercritical CO2 fracturing fluid to 7 mPa·s, and a 9% matrix permeability damage rate and a 0.5 mD permeability decrease value are shown in a 3% CO2 fracturing fluid. However, 3 wt % of commercial CO2 thickener only increases the apparent viscosity of supercritical CO2 fracturing fluid to 3 mPa·s, while the reservoir damage rate increases to 13%. Two thickeners exhibit completely different damage capabilities to the reservoir, and the synthesized CO2 thickener shows excellent characteristics of reducing reservoir permeability and is also conducive to protecting shale reservoirs. Furthermore, supercritical CO2 fracturing fluid containing synthetic thickeners has better temperature and shear resistance compared with commercial thickeners. This may be because the synthesized thickener and the micro grid formed by supercritical CO2 reduce the adsorption in shale crevices, but a large amount of commercial thickeners can adsorb on the surface of shale.
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
FUEL
·
2021
·
IF 6.609
Yi-Bo Li,Xiang Lin,Chen Luo,Zhi-Ming Hu,He-Fei Jia,Ju-Tao Chen,Wan-Fen Pu
Coke is the most important intermediate product during an in situ combustion for maintaining the combustion front stability. Coke is classified as oxidized and pyrolyzed based on the reaction mechanism. The clay minerals exhibit a catalytic effect on the formation and reaction of coke. In this study, a comprehensive experiment was performed to investigate the influence of four clay minerals on oxidized and pyrolyzed cokes. Results showed that these clay minerals exhibited a catalytic effect on the generation and reaction of coke at different levels. In the oxidation process montmorillonite and kaolinite exhibited an excellent catalytic effect on the generation of oxidized coke. In the pyrolysis process, montmorillonite, kaolinite, and illite could promote the breakage of C–S, C–N, and C–O bonds and reduce the number of heteroatoms. In the reaction process, the catalytic effect of montmorillonite induced the aggravation of the polymerization of hydrocarbon derivative with a large molecular weight, resulting in a low activity of the oxidized coke. Moreover, the montmorillonite can induce coke reaction in a low-temperature range, whereas the others exert only suppression effects on coke decomposition. The pyrolyzed coke achieves lower activation energy than the oxidized coke, proving that the pyrolyzed coke can be easily ignited under the reservoir condition. All clay minerals investigated herein can promote the reaction of pyrolyzed coke to different degrees. The montmorillonite achieves the lowest activation energy at 35 °C–100 °C and 350 °C–600°C stages, which benefits the movement of the combustion front.
研究领域:
石油工程
·
催化化学
✓ 已验证
DOI
高影响因子
FUEL
·
2022
·
IF 8.035
Xin Chen,Yiqiang Li,Zheyu Liu,Jian Zhang,Japan Trivedi,Xianjie Li
Particle migration in porous media is of great significance in the areas of formation-water filtration and oil field development. The current theories and methods ignore the effect of particle elasticity on its flow resistance, which is the key point for particle parameters design toward reservoir profile control. Therefore, this paper focuses on the research on the migration process and flow resistance prediction of elastic particles in porous media. Based on the Hertzian contact theory, a migration and plugging model of the elastic particle in porous media is established. Then, core slice injection and microfluidic experiments were used to study the migration process of particles in porous media, which can provide an accurate coefficient for the migration and plugging model. And long core injection experiments were carried out using three kinds of elastic particles (3.7 μm, 8.4 μm, and 21.1 μm) to verify the accuracy of the model. The results show that elastic particles will form a filter cake within 3 cm of the injection end of the core. Combined with the microfluidic visualization experiment, the transport process of elastic particles in porous media can be summarized as the “Gathered and Energized” transport mode with three stages: particles accumulate at the injection end and increase the injection pressure, particles squeeze into the core, and particles deep migration. The migration and plugging model of elastic particles can predict its injection pressure in porous media, which is highly consistent with the experimental data, with an average error of 8.4%. When the reservoir permeability is constant, the injection pressure of elastic particles changes exponentially with the matching factor. In addition, the reservoir permeability also directly affects the injection pressure of elastic particles. When the permeability increases from 1.7 D to 6.0 D, the injection pressure decreases by >70%. This model provides a new method to study the migration of elastic particles in porous media and predict the flow resistance, which is of guiding significance to the bilateral matching design of elastic particles and reservoirs.
研究领域:
石油工程
·
力学
✓ 已验证
产品关联
DOI
高影响因子
ENERGY & FUELS
·
2023
·
IF 5.3
Yining Wu,Qi Luo,Zhongzhong Chu,Yuchen Li,Linghui Sun,Xin Shi,Zijia Li,Wenbo Ren,Bin Yuan
Low oil production and rapid production decline epitomize the challenges of unconventional reservoir development. Rocks in the formation with micro-/nanoscale pore-throat units possess an immense surface area. Consequently, the wettability of rocks plays a crucial role in the relative permeability of oil/water, the injection pressure, the distribution and morphology of residual oil, and hence the ultimate oil recovery. Contact angle, as a frequently used method to evaluate wettability, is susceptible to oil-water saturation, imbibition, and surface roughness of rock slices. In addition, the measurement scale (droplet of several millimeters) does not match the flow scale (pore units in micro- or nanoscale). Therefore, this paper established a new wettability evaluation method based on oil–rock interaction. Molecular dynamics simulation results demonstrated that the interaction energy between the oil molecule and walls with different wettabilities shows a distinct discrepancy. Accordingly, nanomechanics by AFM was utilized to measure the oil molecule–pore wall interaction force. It was found that the interaction force increases with the augmented hydrophobicity of the pore wall due to hydrophobic force. In addition, the reservoir rock wettability index was defined using the oil–rock interaction force in the nanoscale. The wettability index has an excellent linear correlation with the intrinsic contact angle. The wettability evaluation method based on the oil–rock interaction force is more direct, facile, and rapid and overcomes the limitation of the traditional contact angle method.
研究领域:
石油工程
·
纳米技术
·
材料科学
·
地质学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2024
·
IF 5.3
Ziteng Yang,Mingwei Zhao,Weiyu Bi,Yunlong Cheng,Zhenfeng Ma,Kaiwen Liu,Ying Li,Caili Dai
Slickwater has been extensively utilised in deep reservoir fracturing owing to its excellent drag reduction performance, and the polymer drag reducer is the core of slickwater. However, polymer drag reducers may degrade at high temperatures, which limits the application of slickwater in high temperature reservoirs. To increase the temperature resistance of slickwater, a novel temperature-resistant polymer drag reducer was chemically synthesised through free-radical polymerisation using acrylamide (AM), acrylic acid (AA), 2-acrylamide-2-methylpropyl sulfonic acid (AMPS) and N,N-dimethylacrylamide (DMAA). The introduction of temperature-resistant monomers substantially increased the thermal stability of the drag reducer. The rheological measurements revealed that the aqueous polymer solution was a pseudoplastic fluid with good viscoelasticity and thickening properties. At 110 °C, the drag reduction rate of 0.03 wt% polymer aqueous solution could reach 72.57 %, and the drag reduction retention rate was 96.69 % when compared with that at 25 °C. The drag reduction performance was evaluated in relation to displacement, concentration, temperature, pipe diameter, and salinity. Simultaneously, the proportion of factors influencing the drag reduction performance was analysed. Finally, a drag reduction mechanism was proposed. This study is expected to extend the application of slickwater in high-temperature reservoir development.
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
FUEL
·
2023
·
IF 7.4
Mengjiao Cao,Yuan Li,Xuguang Song,Yesheng Chen,Linghui Sun,Xin Shi,Caili Dai,Bin Yuan
Effective development of unconventional resources is impeded by water flooding-related challenges, such as high pressure and under-injection, which hinder the replenishment of formation energy. Nanofluids have shown promise in reducing injection pressure , but traditional nanoparticles (NPs) face limitations in unconventional reservoirs due to their unsuitable size for micro-nano pores and aggregation tendencies. In this paper, novel carbon dots (CDs) with a simple, environmentally benign, and controllable synthetic approach have been developed, and their pressure-reduction performance and mechanism have been systematically explored. The particle size of the CDs could be tailored by a well-timely quenching reaction. CDs nanofluid demonstrated superior stability, dispersibility, and temperature/salinity resistance. In addition, CDs can regulate interfacial properties, including oil/rock and oil/water interfaces. It was found that CDs could be partially absorbed onto pore walls, reducing oil adhesion sites by 39%, altering wettability from oil-wet to neutral, and reducing rock surface roughness by 29.25%. Furthermore, CDs were rapidly adsorbed onto the remaining oil film in the pore space, reducing interfacial tension while solidifying the oil surfaces, increasing shear force around the oil surface by 1.7 times during subsequent water scouring, which makes the oil film break up more readily and remain smaller in size to migrate in the channeling. The modulation of the interface properties by CDs improved the stripping efficiency of the attached oil film and ameliorated the homogeneity and smoothness of flow channel, resulting in a significant reduction in injection pressure. Core displacement tests showed that a 0.1 wt% CDs nanofluid could achieve a pressure reduction rate of 35%. The developed CDs nanofluid represents a promising solution for reducing injection pressure and improving oil recovery in unconventional reservoirs.
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
DESALINATION
·
2025
·
IF 9.8
Shaohua Chen,Norah A Aljeaban,Tianping Huang,Tao Chen
A commonly used scale inhibitor (SI) diethylene triamine penta-(methylene phosphonic acid) (DETPMP) and two series of phosphorous-tagged polymeric SIs (PPSIs) were synthesized to inhibit the formation of calcium-based scale in various brines. Introducing the phosphorus tag facilitates the detection of PPSIs, which is helpful to plan a reasonable operation on squeeze treatment. The two PPSI series are P(DEAP- co -AMPS- co -AA) and P(DEAP- co -SSA- co -AA), including three samples for each copolymer, which were synthesized from diethyl allylphosphonate and various monomers. Generally, DETPMP and the PPSI products exhibited good compatibility in high-salinity water, high efficiency in calcium scale inhibition, and most importantly, the chemical detection at low concentration. One sample from P(DEAP- co -SSA- co -AA) showed the best performance in Ca 2+ scale inhibition with 50:50 formation water and injection water. The PPSI also demonstrated the highest static adsorption onto carbonate. After injection of the chemical solution at 10 wt% followed by a shut-in period of 20 h, permeability of the carbonate core was significantly reduced by treatment with DETPMP. While the permeability remained almost unchanged after the PPSI injection, indicating a low formation damage to the carbonate reservoir. The PPSI concentration was relatively high after the post-flush of reservoir brine, suggesting an effective scale control during the squeeze lifetime. SEM images showed that the cubic and needle-like morphology of CaCO 3 and CaSO 4 scales were not observed in the presence of the PPSI to avoid further crystal growth. XRD results indicated that the intensity of both CaCO 3 and CaSO 4 crystal structures were decreased upon addition of the PPSI.
研究领域:
化学工程
·
石油工程
✓ 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）