Adhesion Characteristics of Crude Oil on Non-Metallic Pipelines During Low-Temperature Gathering and Transportation

To address the lack of theoretical understanding regarding crude oil wall adhesion in non-metallic pipelines and to compare it with the behavior in metallic pipelines, this study investigates the wall adhesion behavior of crude oil in non-metallic pipelines using a self-developed, simulated stirred tank setup. The main factors influencing crude oil adhesion in non-metallic pipelines were identified, and the differences in adhesion behaviors across different pipeline materials were clarified. Additionally, the reasons behind these behavioral differences were explored through contact angle measurements and the interfacial energy theory. The results indicate that the factors affecting the transportation temperature of crude oil in non-metallic pipelines include the overall water content, shear strength, and wax content of crude oil. On average, the amount of adhered crude oil in the three types of non-metallic pipeline was lower than that in the metallic pipelines. Among them, the flexible, composite non-metallic pipeline showed the greatest reduction in average adhered oil mass by 22.86%. This significant reduction is attributed to the reduced adhesion of crude oil on the non-metallic surfaces. Therefore, using non-metallic pipelines in crude oil transportation networks is advantageous for implementing low-temperature gathering and transportation processes.