Investigation of hydrate inhibitor tracking in oil-gas-water multiphase flow pipelines

As oil and gas exploration progressively moves into deepwater regions, flow assurance in multiphase transport pipelines has become a critical issue. The complex conditions in deepwater environments often lead to the formation of solid hydrates, which can block pipelines. Therefore, the injection of hydrate inhibitors has become a common practice. In engineering practice, conservative dosing rates are typically adopted to ensure safety margins, but this often leads to a significant increase in costs. This paper presents a steady-state computational model to determine the distribution of inhibitors along the pipeline. The innovation lies in combining multiphase flash calculations with pipeline flow modeling, offering high accuracy and a wide range of applicability. This model is designed with modular flexibility, allowing substitution of different steady-state flow models and thermodynamic models, thereby extending its adaptability to diverse engineering scenarios. The computational results are compared with those from OLGA (a commercial software for multiphase flow simulation, version 2022.1), and the results demonstrate that the proposed method achieves high accuracy, indicating that it can serve as a reference for optimizing inhibitor dosage.