Flow pattern, pressure drop and inclination analysis on liquid-liquid two phase flow of waxy crude oil in pipelines using PIPESIM

Abstract

Produced water is a water that comes out with the crude oil during the production of the well. It contains non-soluble and soluble oil or organics, dissolved and suspended solids with different chemicals used during production process. Thus, it must be properly accounted as it affects the economical productivity of crude oil and separation efficiency as a result of stubborn emulsions between crude oil and water. Thus, a simulation study was conducted using PIPESIM to predict the flow pattern and pressure drop of waxy crude oil and water flow in horizontal and inclined pipelines (i.e., -15° from horizontal). In this simulation study, water cuts were ranging from 0% to 90% while the flow rates were ranging from 2.03 to 16.21 cm3/s. The study comprised fluid modelling, physical modelling and running the simulation with the most suitable multiphase flow correlation in PIPESIM. This simulation study used the waxy crude oil has 16.15% of wax content and simulation was performed at 30°C. The validity of the simulation results was accomplished by comparing the published findings. There were only two types of flow patterns that can be identified by PIPESIM; stratified wavy and dispersed flow. The investigations proved that pressure drop was greatly influenced by flow rates and flow patterns. By decreasing the inclination angle, the boundary between the stratified and dispersed flow regimes shifted to the upper left of the flow pattern map while showing a higher pressure drop than horizontal pipeline due to the combined effect of pressure difference and gravity. The simulation results can be used as a platform for better understanding on more complex cases of gas, oil and water concurrent flow in pipelines.