Browsing by Author "Moropane, Isaac Sekontshe"

Now showing 1 - 1 of 1
  • Thumbnail Image
    Item
    Numerical investigation of selective withdrawal of brine from salt cavern with entrainment of the light phase oil
    (2024) Moropane, Isaac Sekontshe
    This paper presents a numerical simulation of selective withdrawal of brine from salt cavern with entrainment of crude oil. Selective withdrawal is the siphoning of one layer of fluid from two immiscible fluids and avoiding the entrainment of other fluid. A trial of three incline siphons (60o , 75o and 90o ) were utilized and each passing through 2.54 cm silicon oil layer and face down below the liquid-liquid interface drawing water upwards. The siphons had a submergence depth of 2.54 cm below the liquid-liquid interface. The simulation was done using the software Ansys Academic, Student 2021 R1. The flow was simulated using two dimensions CFD. The volume of Fluid model and Pressure-based solver were adopted for this simulation. The turbulence model used in the CFD was standard k-epsilon. Semi-Implicit Method for Pressure Linked Equations (SIMPLE) algorithm was adopted for pressure velocity coupling. The results showed that, for avoiding oil entrainment, 90o siphon is better followed by 60o inclined, whereas the 75o inclined was the worse. The results obtained from CFD simulation were validated using experimental data and found to agree. The paper's findings can be useful for Petroleum Engineers to reduce oil entrainment in selective withdrawal from salt caverns in the Strategic Petroleum Reserve (SPR). By predicting the transition from selective withdrawal to oil entrainment, an improved design can optimize the withdrawal process. The design can be enhanced by adjusting the withdrawal rate, pressure, and siphon orientation to minimize the transition from selective withdrawal to oil entrainment. The consequences of oil in the brine system necessitate the separation of oil from the brine, the transfer of oil entrainment back into the salt caverns, and clean-up to avoid environmental contamination. This process of separating and cleaning oil from brine in a brine pond is more time-consuming and expensive.