Designing Ultra-Low Hydrate Adhesion Surfaces by Interfacial Spreading of Water-Immiscible Barrier Films

Abstract

Clathrate hydrates are icelike solid substances that can form inside oil and gas pipelines and are responsible for flow blockages, sometimes leading to catastrophic failures. Minimizing hydrate formation and adhesion on pipeline surfaces can effectively address this problem. In this paper, we achieve the lowering of the adhesion of cyclopentane hydrates by promoting a cyclopentane barrier film between the hydrate and solid surface. The presence of this interfacial liquid film depends on the relative spreading of cyclopentane on the solid surface in the presence of water. We study the role of surface chemistry and surface texture on the spreading characteristics of such interfacial films and their impact on hydrate adhesion. The use of the spreading coefficients as design parameters could take us a step closer to the development of effective passive antihydrate surfaces.

Anti-gas hydrate surfaces: perspectives, progress and prospects

“…16b, the roughness on two hydrophobic surfaces (OTS-coated and FS-coated surface) were controlled by tuning the distance, b , between microposts. 163 For textured FS-coated surfaces, the adhesion force first decreased and then increased with changes in surface roughness. Obviously, increasing the post spacing firstly decreased the contact area between the hydrate and surface and decreased the adhesion force.…”

“…184 The above-mentioned studies carried out by Das et al supported such a conclusion. 163 Although the OTS-coated surface had higher surface energy than the FS-coated surface, the hydrate adhesion force on the OTS-coated surface was lower. The reason can be explained as the nonpolar –CH 3 group on the OTS surface was unfavorable to water, whilst the increased polarity of fluorinated groups on the FS surface enhanced the surface–water interactions.…”

“…In quantifying hydrate adhesion in most experiments, a micro-mechanical adhesion apparatus was utilized to measure the adhesion force between hydrate particles and surfaces. 163–165 Compared to intrinsic ice adhesion being widely investigated by atomistic modeling and molecular-dynamics simulation in recent years, 166–171 intrinsic hydrate adhesion at the atomistic level is, however, largely unexplored. Nevertheless, understanding ice adhesion could nonetheless shed light on the origin of hydrate adhesion, or at least offer some relevant mechanistic hints and parallel insights.…”

“…In a study carried out by Das et al , contrasting results were observed. 163 Specifically, silicon surface, silicon surfaces coated with octadecyltricholorosilane (OTS) and tridecafluoro-1,1,2,2 tetrahydrooctyl-trichlorosilane (FS), with surface energies of ∼53 mJ m −2 , ∼24 mJ m −2 and ∼8 mJ m −2 , respectively, were subjected to hydrate-adhesion tests. The results showed that the OTS-coated surface had the lowest hydrate adhesion and the most minimized hydrate accumulation atop, which indicated that other parameters might also play important roles in hydrate adhesion.…”

Preventing Hydrate Adhesion with Magnetic Slippery Surfaces

“…However, the fluid can deplete over time; therefore, a ferrofluid gel was also used to prevent the loss of the coating. 33−35 The ferrofluid coating was studied with a model hydrate using tetrahydrofuran (THF), which is commonly used for testing KHIs. 23,28,36 Ideally, the ferrofluid would be tested under pressure, but that is nontrivial, and a specially designed system would be required, which is why THF hydrates were used.…”