Article
Energy & Fuels
Weiguo Liu, Mengmeng Zhang, Zaixing Liu, Chen Lang, Jingsheng Lu, Qingping Li, Yanghui Li
Summary: Hydrate formation experiments were conducted under the production conditions of the Lingshui gas field using a high-pressure rheometer, and the evolution of viscosity was investigated. The study found that the slurry viscosity changed in stages during hydrate formation, with the aggregation of hydrate particles being the main cause of the significant increase in viscosity. The more severe the temperature and pressure conditions, the faster the hydrate formation and the greater the increase in viscosity. Additionally, a critical hydrate volume fraction was proposed for a sharp increase in viscosity, which can help in predicting hydrate formation and preventing blockages in natural gas production.
Article
Engineering, Chemical
Xingxun Li, Cunning Wang, Qingping Li, Weixin Pang, Guangjin Chen, Changyu Sun
Summary: Understanding the mechanisms of hydrate formation and dissociation through microfluidic visualization in a porous micromodel is essential for natural gas hydrate exploration. Different methane hydrate formations and dissociation behaviors were observed, with significant differences between methane-pure water and methane-brine systems. The study also highlighted the impact of multiple formation-dissociation processes on gas-liquid interfaces and subsequent hydrate behaviors.
CHEMICAL ENGINEERING SCIENCE
(2022)
Article
Engineering, Chemical
Dongxu Zhang, Qiyu Huang, Rongbin Li, Wei Wang, Xiangrui Zhu, Huiyuan Li, Yijie Wang
Summary: The presence of waxes strengthened the inhibiting effect of asphaltenes on hydrate formation in asphaltene-containing water-in-oil emulsions. Wax crystals dispersed in the bulk phase and got adsorbed at water-oil interface through the synergistic effect with asphaltenes, inhibiting the dissociation of hydrates.
CHEMICAL ENGINEERING SCIENCE
(2021)
Article
Energy & Fuels
Peng Xiao, Guang-Jin Chen, Chang-Yu Sun, Li-Wei Cheng, Xing Huang
Summary: Morphology observation is an important approach for studying hydrate formation mechanisms. The study found that under reciprocating impact, forming and fracturing of hydrate shells significantly improved hydrate formation, and the memory effect during re-formation affected nucleation rate and gas storage capacity.
Article
Energy & Fuels
Xingxun Li, Ming Liu, Qingping Li, Weixin Pang, Guangjin Chen, Changyu Sun
Summary: This study investigated the formation and depressurization-induced dissociation behaviors of methane hydrate in porous media using a high-pressure transparent micro-packed bed reactor. The results revealed the effect of methane bubble dispersion on hydrate formation, observed hydrate reformation during depressurization, and demonstrated the impact of fluid extraction rate on hydrate reformation. The dissociation process of hydrate and fluid migration phenomena in the pore spaces were also visualized.
Article
Engineering, Environmental
Yuechao Zhao, Xu Lei, Jia-nan Zheng, Ming Li, Michael L. Johns, Mingxing Huang, Yongchen Song
Summary: Gas hydrates are considered promising for gas storage, energy transportation, and seawater desalination. Using MRI, researchers were able to non-invasively image the formation of opaque hydrates from CO2 and water in a cylindrical vessel at low temperature and high pressure. They observed dense hydrate layers forming consistently at the gas-water interface, porous hydrate layers above it, and complex dendritic formations in the water phase below.
CHEMICAL ENGINEERING JOURNAL
(2021)
Article
Energy & Fuels
Shang-Fei Song, Shun-Kang Fu, Qing-Yun Liao, Bo-Hui Shi, Hong-Ju Chen, Jing Gong
Summary: This study investigates the effects of micron-sized sands on hydrate formation, dissociation, and viscosity in a gas-water-sand system. The experimental results show that the presence of sand slightly prolongs the hydrate induction time and has little effect on the kinetics of hydrate formation. There are three variations of hydrate slurry viscosity during the formation process, and an appropriate sand size helps reduce the randomness of viscosity change.
Article
Energy & Fuels
Shikun Tong, Pengfei Li, Fengjun Lv, Zhiyuan Wang, Weiqi Fu, Jianbo Zhang, Litao Chen, Xuerui Wang
Summary: This study investigates the impact of wax on hydrate formation and dissociation in water-in-oil emulsions. Experimental results show that wax forms a shell barrier on the oil-water interface, increasing transfer resistance, and decreases water droplet size, increasing the oil-water interface area. Wax exhibits dual regulation on hydrate formation, with a dominant inhibition effect at concentrations above 6 wt%. Wax also dominates the regulation of hydrate dissociation, increasing the difficulty of hydrate plug removal. These findings are valuable for hydrate risk assessment and flow assurance design in deep-water oil and gas fields.
Article
Energy & Fuels
Moumita Maiti, Prathibha Pillai, Aniruddha Sharma, Ajoy Kumar Bhaumik, Ajay Mandal
Summary: This study investigates the effect of two ionic liquids on the formation and dissociation of gas hydrates and finds that they are effective inhibitors. The inhibition performance of the ionic liquids increases with increasing alkyl chain length.
Article
Energy & Fuels
Moumita Maiti, Prathibha Pillai, Aniruddha Sharma, Ajoy Kumar Bhaumik, Ajay Mandal
Summary: In this study, the effect of two ionic liquids on the formation and dissociation of hydrates was investigated. The results showed that these ionic liquids were effective in inhibiting hydrate formation both thermodynamically and kinetically. The induction time and formation rate of hydrates were significantly increased in the presence of these ionic liquids compared to pure water. Additionally, the performance of the ionic liquids in hydrate inhibition increased with increasing alkyl chain length.
Article
Energy & Fuels
Cuiping Tang, Yanan Zhang, Deqing Liang
Summary: Adding hydrate inhibitors, such as Es-PVCap-OH, is an effective method to prevent gas hydrates from blocking pipelines and equipment. This study investigated the inhibitory performance of Es-PVCap-OH for methane hydrate formation and compared it with the kinetic inhibitor PVCap. The results showed that Es-PVCap-OH exhibited better inhibitory performance and changed the morphology of the hydrate structure.
Article
Chemistry, Physical
Zhigao Sun, Linchen Zhou
Summary: This study investigates the effects of additives, such as Tween80, decanoic acid, and dodecyl alcohol, on hydrate crystal growth. The addition of Tween80 enhances the stability of hydrate formation, while the mixture of decanoic acid and dodecyl alcohol alters the growth mode of hydrate crystals. Moreover, the additives also affect the morphology of the hydrate crystals.
JOURNAL OF MOLECULAR LIQUIDS
(2022)
Article
Engineering, Chemical
Andrey Yu. Manakov, Konstantin E. Kuper, Arkadi N. Drobchik, Alexey K. Sagidullin, Matvei E. Semenov, Andrey S. Stoporev
Summary: This study investigates the formation of xenon hydrate in a water-in-oil emulsion using radiographic and DSC techniques. The results show that the formation process occurs in two stages, with hydrate proliferation near the emulsion-gas boundary in the first stage and slow growth throughout the sample in the second stage. The findings improve the understanding of hydrate growth kinetics in static water-in-oil emulsions.
CHEMICAL ENGINEERING SCIENCE
(2023)
Article
Engineering, Chemical
Mohammad Tariq, Mario R. C. Soromenho, Luis Paulo N. Rebelo, Jose M. S. S. Esperanca
Summary: This study investigates the effect of various variables on the formation/dissociation process of CO2 + H2O hydrate systems and demonstrates how to obtain the hydrate equilibrium curve more efficiently and accurately. The experiments provide qualitative indications of mass transfer and kinetics, with potential implications for energy and environmental applications of hydrate technology.
CHEMICAL ENGINEERING SCIENCE
(2022)
Article
Energy & Fuels
Yu Zhang, Lei Zhang, Chuan-Yu Zhu, Li-Xin Xu, Xiao-Sen Li, Zhao-Yang Chen
Summary: The formation rates of methane hydrate are significantly affected by the grain size of the sediments, with lower rates observed in sand compared to powders. The final water conversion rate is similar in powders and can reach nearly 100% with sufficient gas supply, while the rate declines sharply at a certain water conversion point in all three types of porous media.
