EFFECTS OF FLOW REGIME ON SOLIDS DEPOSITION IN MULTIPHASE PETROLEUM FLOW

摘要

This paper has numerically researched the effects of flow regime on particle trajectories as well as solids deposition behaviours in multiphase petroleum flow. In this study, the flow patterns frequently encountered in oil and wet-gas petroleum pipelines were targeted, including annular mist flow, stratified smooth/wavy flow, slug flow, and elongated/dispersed bubble flow. Distributions of the liquid-phase velocity in gas-liquid two-phase flow were determined by means of theoretical derivation, numerical simulation, or using commercial software. Based on the acquired liquid-phase velocity fields, particle velocities were calculated via Newton's second law. Subsequently, particle trajectories were tracked by solving the motion equation. Under an approximation of wall effect, the amount of solids deposition in multiphase petroleum flow was quantified. Furthermore, solids deposition behaviours with respect to solids/liquids properties, operating parameters, and pipeline terrain were characterized. Efforts were made to understand the solids deposition behaviours in multiphase petroleum pipelines which have been well known to initiate and accelerate localized pitting corrosion. This work was performed in conjunction with the ongoing development of our company's internal corrosion prediction model (ICPM) which is capable of predicting solids deposition as well as under-deposit pitting corrosion rate.