Experimental study on the formation and agglomeration of tetrahydrofuran hydrate under flowing condition

Wang, Wuchang; Liu, Shuai; Wang, Xiao Yu; Li, Yuxing; Song, Guangchun; Yao, Shupeng

doi:10.1016/j.ijrefrig.2020.06.012

Cited by 14 publications

(7 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In the hydrate slurry system, hydrate particles were mostly dendritic or spherical, − and the different shapes resulted in the particles having different migration speeds based on this research. According to a large number of statistical measurements, the spherical particles migrated faster than dendritic particles with the same length (the average of the longest and shortest distance for dendritic hydrates).…”

Section: Resultsmentioning

confidence: 75%

“…On this basis, the author proposed that the entire deposition process can be divided into two stages. In the first stage, the natural gas hydrate particles are flaky and branched or more complex initially due to the continuous stirring as shown in Figures . − The complex dendritic agglomerates quickly float up due to the faster migration speed (Chapter 2.2.1) and form a network structure after stirring is stopped, as shown in Figure , which hinders the upward migration of hydrates in the lower layer, forming a clear bed distribution. Complex hydrate particles which have a larger diameter have already floated to the gas–liquid interface before the formation of the network barrier due to the faster-floating speed as mentioned above.…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Evolution Process of Natural Gas Hydrate Deposits in Water-Dominated Systems

Liu

Song

et al. 2022

Energy Fuels

Self Cite

View full text Add to dashboard Cite

In order to improve the operation safety of the multiphase flow in the subsea pipelines and facilitate the development of deep-sea oil and gas resources, the evolution process of different hydrate deposits has been studied based on high-pressure reactors and focused beam reflectance measurement (FBRM). The results show that larger hydrate formation (6% vt hydrate concentration) can form layered deposits but smaller (3% vt hydrate concentration) corresponding to the suspended slurry, and the reduction rate of the fixed bed thickness is greater than the moving bed. Microscopic images show that the downward transportation of pore water dominates the evolution process when the moisture content is higher than 87%. The evolution mathematical model of hydrate deposit thickness which is based on Darcy’s law is in good agreement with the experimental results, proving the properties of porous media in hydrate deposits. The migration rate and permeability of porous hydrate particles are positively related to the particle size, both showing a linear relationship at the microscopic scale. The deposits with a uniform particle size distribution are more difficult to stratify and thus more suspended, which is conducive to the safety of pipeline transportation compared with the layered deposits. On these bases, the mechanism and mathematical model of hydrate deposit stratification and evolution are established.

show abstract

Section: Resultsmentioning

confidence: 75%

Section: Resultsmentioning

confidence: 99%

Evolution Process of Natural Gas Hydrate Deposits in Water-Dominated Systems

Liu

Song

et al. 2022

Energy Fuels

Self Cite

View full text Add to dashboard Cite

show abstract

“…Hexagonal crystal flat plates were also sighted floating over the interface upon the hydrate incipience (Figures and ). Previous studies on hydrates with tetrahydrofuran, − methane, − and a mixture of hydrocarbon gases , also reported on the formation of similar floating polygonal plate crystals.…”

Section: Resultsmentioning

confidence: 81%

Hydrate Growth over a Sessile Drop of Water in Cyclopentane

Kamel

Lobasov

Narayan

et al. 2023

Crystal Growth & Design

View full text Add to dashboard Cite

Liquid cyclopentane is frequently used in hydrate formation studies as an analogue of natural gas because cyclopentane hydrates are stable above the ice melting point at ambient pressure. In this study, hydrate growth was established on a sessile water drop of 11 mm in diameter and 4.5 mm in height (volume of 0.25 mL) immersed in liquid cyclopentane. The hydrate formation mechanism and growth processes were observed optically over an extended range of subcooling temperatures from 5.1 to 15.2 °C, with the cyclopentane bulk temperature maintained in different experimental runs between 2.6 and −7.5 °C. Qualitative and quantitative comparisons were performed to confirm the absence of ice freezing during hydrate formation, and thus, the lack of contamination of the latter from the former in the experiments. Different transformations in the hydrate film morphology were registered from macroscopic observation over the considered range of subcooling temperatures, with the hydrate crystals composing the film taking the form of polyhedral, dendritic, or spherulitic structures. It was also found that the hydrate growth rate varied depending on the subcooling temperature, with the variation of the growth rate as a function of this temperature changing from a power to an (approximately) linear law with an increase in the degree of subcooling. We postulate that hydrate film growth can be governed by different mechanisms, whose roles change over the range of explored subcooling temperatures.

show abstract

“…In order to validate the formation of the THF hydrate structure, Raman spectroscopy measurements were illustrating the THF molecules only occupy the large 5 12 6 4 cages of the sII hydrates. 52 The results in Fig.…”

Section: Effect Of Nacl On the Crystal Growth Rate And Morphologymentioning

confidence: 99%

“…7 One characteristic of gas hydrates is the ability to store gas at high density, approximately 164 m 3 of gas at standard temperature and pressure (STP) for every 1 m 3 of gas hydrate. 1 Many research efforts have been conducted that exploit this characteristic for hydrate-based technologies, such as CO 2 capture and storage, [8][9][10] refrigeration systems, 11,12 and seawater desalination. [13][14][15] Both flow assurance and hydrate-based technologies often involve salts.…”

Section: Introductionmentioning

confidence: 99%