Investigation on the oil permeation–adsorption–diffusion combined action mechanism of the adsorbed layer for flexible oil storage in waters

A novel method entitled flexible oil storage in waters is proposed, aiming to address the limitations of current oil storage systems and enhance the country's oil storage capacity. However, oil contamination severely restricts its applicability. To ensure the environmental sustainability of the method, the adsorbed layer is added outside the oil bladder, and the study investigates the material and the action mechanism of the adsorbed layer for flexible oil storage in waters. The results show that, with long breakthrough time and low oil concentration as criteria, the reed straw biochar is more suitable as the adsorbed layer filling material compared to the coconut shell and the apricot shell biochar and the fluorinated ethylene propylene copolymer is more suitable as the adsorbed layer membrane material compared to polyvinyl chloride. The adsorbed layer action mechanism involves multiple interactions, including permeation, adsorption, accumulation, and diffusion. They are coupled and together influence the adsorption effect. The empirical formula for the adsorbed layer's lifespan is derived, which helps in designing the adsorbed layer to satisfy specific lifespan requirements. This study provides theoretical and engineering guidance for the application of flexible oil storage in waters, contributing to the development of oil storage techniques.