Journal of Marine Science and Engineering
·
2023
·Vol. 11
·期 2
·282
·
IF 2.9
Zhiguang Song,Shiyuan Cui,Cuiping Tang,Yong Chen,Deqing Liang,Sibo Wang
Polyvinylcaprolactam (PVCap) is an economic kinetic inhibitor for hydrate formation in pipelines during oil and gas transportation. However, its application is limited because of the low inhibition performance under certain conditions. In this work, a modified PVCap on its chain end is proposed. 2-amino-3-propionic acid mercapto-terminated polyvinyl caprolactam (PVCap-NH2-COOH) was synthesized and its performance as a KHI for methane hydrate formation was evaluated under different conditions. Results showed that the performance of PVCap-NH2-COOH as a KHI was better than that of PVCap at the same concentrations. Gas hydrate samples with 1 wt.% PVCap-NH2-COOH were measured using Raman spectroscopy, XRD, and cryo-SEM. PVCap-NH2-COOH had a selective action on a specific crystal surface of the hydrates and could prevent methane molecules from entering large cages. Its inhibition ability increased with the decrease in the occupancy rate of large cages. The morphology of the gas hydrate crystal changed from porous in a pure water system to a chaotic but compact structure state in the system with PVCap-NH2-COOH.Keywords:natural gas hydrate;formation;inhibition;modification
研究领域:
化学工程
·
材料科学
·
物理化学
✓ 已验证
DOI
高影响因子
FUEL
·
2024
·
IF 6.7
Yuhuan Bu,Zilong Lu,Chang Lu,Huajie Liu,Shenglai Guo,Hexing Liu,Rui Ma,Zhen Zhang,Mengran Xu
Deepwater cementing technology holds non-negligible significance in ensuring the safe exploitation of deepwater oil and gas resources, and maintaining stability of hydrate formations is crucial for deepwater cementing. Traditional solutions primarily focus on reducing the cement’s hydration heat evolution but fail to effectively address the issue of hydrate dissociation. Therefore, our previous work outlined the design and optimization of a novel hydrate dissociation inhibitor, PVCap/dmapma, and its physical synthesis and evaluation are explored in this study. The method of molecular simulation and experimental study was utilized to establish an evaluation method of hydrate dissociation inhibitor under cementing environment, to investigate the hydrate decomposition inhibitory, and to determine the relatively optimal synthesis conditions and process. PVCap/dmapma exhibits excellent ability to delay the hydrate dissociation, and no adverse effects on cement thickening and mechanical properties compared to Lecithin. Our findings provide a certain theoretical foundation for the development of hydrate dissociation inhibitors for cementing and hold significant implications for ensuring the safe exploitation of deepwater oil and gas resources.
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
Processes
·
2026
·Vol. 14
·期 3
·402
·
IF 2.8
Shidong Zhou,Gan Qiu,Yang Liu,Wei Wang,Zhikuang Liang,Yongqing Zhang
During the transportation of oil and gas pipelines, the adhesion and aggregation of hydrate particles on the pipe wall are prone to cause pipeline blockage, which seriously impairs the safe and efficient transportation of energy. Taking cyclopentane hydrates as the research object, this study investigated the effects of contact time, wall wettability, and the concentration of kinetic hydrate inhibitor poly(N-vinylcaprolactam) (PVCap) on the adhesion force between hydrates and the wall of X80 pipeline steel by combining a high-precision micromechanical force measurement system with microscopic morphology observation and analysis. The results show that the adhesion force increases with prolonged contact time: it is dominated by capillary liquid bridge force in the initial contact stage with slow growth, and after exceeding the critical time, the sintering effect becomes the dominant factor, leading to a rapid rise in adhesion force that eventually tends to stabilize. Wall wettability significantly influences the adhesion force, and enhanced wettability improves the adhesion force by increasing the liquid bridge volume and the hydrate–wall contact area. PVCap concentration exerts a non-monotonic effect on adhesion force—first decreasing and then increasing. At low concentrations (0.25–1 wt%), PVCap molecules adsorb on the hydrate surface to form a physical barrier, reducing adhesion force. At high concentrations (1.5–2 wt%), excessive PVCap damages hydrate shell integrity, releasing free water to expand the liquid bridge volume and increase adhesion force. This study provides a theoretical basis for eliminating or reducing hydrate blockage in deep-sea oil and gas pipelines.
✓ 已验证
产品关联
DOI
高影响因子
KEY ENGINEERING MATERIALS
·
2017
·
IF 0
Ke Le Yan,Hong Xing Zhang,Ying Li,Bing Zou,An Shan Xiao,Ming Ma
A new kind of kinetic hydrate inhibitor (KHI) named KL-1 as the ramification of poly (N-vinyl caprolactam) (PVCap), was synthesized successfully by use of precipitation polymerization. The hydrate inhibition performance of KL-1 was assessed in a high pressure sapphire cell, and the onset time of hydrate formation and maximum subcooling were determined by the visual observation method and compared with the commercial KHIs, including Inhibex 501 and VC-713. Meanwhile, the synergic effect between ethanol and KL-1 developed was also studied in this work. The experimental results show that the onset time of KL-1 measured increases with the increase of the dosage and decrease of subcooling. Compared with the system without kinetic hydrate inhibitor, the morphological behavior of hydrate crystals in the systems containing KL-1 is different, and the hydrate crystals only grow to the gas phase with the hydrate formation. Additionally, based on the measurement of inhibition time, the inhibition performance of KL-1 is superior to Inhibex 501 and VC-713, and shows higher maximum subcooling at the similar conditions. Finally, we also demonstrated that ethanol can be used as synergist to improve the performance of KL-1 remarkably at suitable dosage.
研究领域:
化学工程
·
材料科学
·
高分子化学
✓ 已验证
DOI
危险品化学品经营许可证（带存储）