Study on the Effect of Temperature on the Adhesion Force Between CH4 Hydrate Particles in High-Pressure Systems Containing Heavy Hydrocarbon Components

In deepwater oil and gas development, when heavy hydrocarbon components such as wax and asphaltenes coexist in crude oil within pipeline multiphase flow systems, the coupled deposition and blockage of multiple solid phases in the multiphase flow system becomes complex. Studying the effect of heavy hydrocarbon components on the microscopic aggregation behavior of hydrate particles is crucial. In this paper, a self-designed high-pressure visual micromechanical force experimental apparatus was used to investigate the impact of temperature on the microscopic adhesion force between CH4 hydrate particles in three different oil-phase systems: pure oil phase, wax-containing oil phase, and asphaltene-containing oil phase. Adhesion forces between CH4 hydrate particles were measured at temperatures ranging from 1 °C to 5 °C. The results show that, in the pure mineral oil system, the adhesion force between hydrate particles increases with temperature. At 1 °C, the adhesion force is 1.98 mN/m, and at 5 °C, it increases to 6.81 mN/m, a 243.9% increase. The hydrate particle surface gradually smooths and densifies, transitioning to a water-film-wet surface, which leads to increased adhesion between the particles. In the wax-containing system, the presence of wax crystals significantly alters the structure and wettability of the hydrate particle surfaces, causing the particles to exhibit hydrophobicity. Through the dual action of physical coverage and heat/mass transfer regulation, the adhesion force between particles in the oil phase system is reduced. In the asphaltene-containing system, the presence of low concentrations of asphaltenes effectively reduces particle adhesion and agglomeration tendencies. At higher concentrations, asphaltene deposits form a flocculent coverage on the surface of the hydrate particles, reducing the inhibitory effect of asphaltenes.