水合物颗粒与矿物表面间粘附力特性及其影响因素

In the process of hydrate mining, the droplets and bubbles in pipeline can be turned into hydrate particles under the environmental conditions. The occurrence of hydrate particle aggregation can cause blockage, leading to potential safety problems. Adhesive force is the key to exploring the flow safety of mining pipeline and the accumulation/deposition mechanism of hydrate particles. At present, the relevant researches focus on the measurement and characterization of the adhesive force between hydrate particles or between particles and surface in transport process. However, documents on the effects of mineral wettability and surface roughness on the adhesion of hydrate deposits are rarely seen. In this study, the adhesive force between hydrate particle and carbon steel surface treated by different methods as well as mineral surface, such as quartz, malachite, calcite and kaolinite were measured and analyzed using the adhesive force measurement experimental system. The results show that the adhesive force of hydrate particles to mineral surface is 3-6 times that of hydrate particles to carbon steel surface, due to the wettability difference. In addition, the adhesive force between hydrate particles and mineral surfaces is also affected by contact time, as shown by the strengthened adhesive force of hydrate particles with calcite and kaolinite surfaces under prolonged contact. The effects of ionic surfactants on hydrate growth rate and adhesion were also investigated, and it was pointed out that the change of contact area between particles and water film on mineral surface serves to change the morphology of hydrate particles from layered structure to needle-like structure. Finally, in comparison of the experimental results with theoretical calculation, we concluded that the strong hydrophilicity of the mineral surface is key to the differences.