Modeling an Ascending Nitrogen Gas Bubble in a Medium Crude Oil by Lattice Boltzmann Method

Carolina Del Valle Silva

doi:10.11648/j.fm.20180401.12

Abstract

The study and modeling of oil biphasic systems, liquid-liquid and liquid-gas, focus mainly on the details of the modifications and application of the numerical methods itself. The correspondence between theoretical and experimental results and the information needed to apply a certain numerical method, usually remain in the background. On the other hand, in the particular case of the prediction of minimum miscibility pressure, extremely important parameter in oil exploration, references that show qualitative and numerical data associated with the characterization of the systems are scarce. The above reasons motivated the realization of this work. We used the Lattice Boltzmann Equation method to model a two-dimensional system of the displacement of a nitrogen gas bubble through a medium crude oil, under different pressure conditions keeping the temperature constant. According to experimental data, the bubble is not miscible by the crude, under a pressure range of 5000 psi to 6500 psi; nevertheless, the bubble is miscible in the range of 7000 psi to 7500 psi. Throughout simulations performed under similar conditions, we showed that it can be inferred the critical pressure range of miscibility of a medium crude oil.

Highlights

The Lattice Boltzmann Equation (LBE) method is based on representation of particles collections as a unity
Lishchuk BGKGuo area of 0.92 mm2, about 59% compared to the previous area and 86% compared to the starting area. This result whatever agrees with the improved oil recovery (IOR) Gas Injection Laboratory experimental result, as it is shown in the snapshot of the dynamics, displayed in Figure 8, with a critical P value of 7000 psi, and a similar area change and area reduction about 0.66 mm2, around 66% compared to previous area
The results showed that it was possible to reproduce the dynamic behavior of a nitrogen gas bubble passing through a column filled of medium crude oil, under miscibility and immiscibility pressure conditions, keeping the temperature constant

Summary

Introduction

The Lattice Boltzmann Equation (LBE) method is based on representation of particles collections as a unity. Khamehchi et al [10] studied two important properties of crude oil, bubble point pressure (Pb) and formation volume factor (Bob) using genetic programming Following this line of research, our work used a general purpose mesoscopic simulation package, the Lattice Boltzmann Equation (LBE), to model a two dimensional system of the displacement of a nitrogen gas bubble through a medium crude oil, under three different pressure (P) conditions while keeping the temperature (T) constant, in order to estimate the minimum miscibility pressure (MMP). At or above the MMP, miscibility can develop through a Carolina del Valle Silva and Luque Montilla Jesús Miguel: Modeling an Ascending Nitrogen Gas Bubble in a Medium Crude Oil by Lattice Boltzmann Method vaporizing process, a condensing process, or depending on the reservoir characteristics, a combination of the two processes. The MMP determination is essential and in the present day, there are a number of experimental techniques for the determination of MMP like slim tube, vanishing interfacial tension (VIT) and rising bubble apparatus (RBA) [12]

Rising Bubble Experiment

Theoretical and Experimental Data Model

Discussion and Results

Conclusion