A Rapid Method to Predict Minimum Miscibility Pressure Through Interfacial Tension Test and Visual Observation

Abstract

The minimum miscibility pressure (MMP) CO2 injection performs in enhanced oil recovery (EOR) method to increase sweeping efficiency and reduce oil/CO2 interfacial tension (IFT) also advantageous to the environmental in term of gas emissions for carbon capturing. There are several methods to achieve reliable value of MMP such as slim tube test, raising bubble apparatus, vanishing IFT, swelling test, and visual observation. However, these methods have certain limitations, which leads to the development of new techniques for a wide range of applications. In this paper, a rapid method that integrated IFT test with visual observation was investigated. Based on the test, the pressure is plotted against the IFT to predict the MMP for temperature 60 °C and 66 °C. In the meantime, visual observation during the test is also conducted to identify the occurrence of miscibility. The combination of both methods may provide much faster MMP prediction because the test consumes a small amount of hydrocarbon samples. The outcomes of this research clearly suggest that the MMP values resulted from IFT test and visual observation considerably agree with each other.

Minimum CO2 Miscibility Pressure Evaluation using Interfacial Tension (IFT) and Slim-tube Hybrid Tests

“…The recovery factor (RF) increases with pressure until a break-over point is reached, as depicted in Figure 6, where the curve slope changes at about 90% RF. 17 The MMP from this test aligns well with the simulation if very accurate reservoir data are taken. 6,11,13,14,21 Yet, a combination of IFT and slim-tube methods has rarely been used to estimate MMP.…”

“…Dong et al 4 recommended that MMP could be determined using visual observation during a slim-tube test experiment. This method was also proven by Abdurrahman et al 17 to predict MMP. The IFT test process used for this study is depicted in Figures 8 and 9.…”

“…Thus, it is advantageous to use this technique. It also proves that the slim-tube test is an appropriate method to estimate MMP, as suggested by Abdurrahman et al 17,25,26 Second, the MMP is determined through simulation using the equation of state (EOS). Third, visual observation is conducted using photos or videos, as previously done by Jessen and Orr 22 and Abdurrahman et al 17,25,26 In the current case, the shape of the oil drop is observed until it disappears in the display cell.…”

“…The estimated MMP of the oil−solvent system is represented by the intersection between the two trend lines in the graph. The experiment conducted in the current study refers to two prior studies, i.e., Abdurrahman et al 17 and Adel et al 18 Figure 3 depicts the slim-tube test experiment diagram. The system involves of a high-pressure cell with a 12 mm diameter, 80 mm height, 16 mm thickness, and a sapphire-based material.…”

“…The study specifically proposed that MMP can be estimated when a CO 2 -rich phase and CO 2 vapor interface disappear. In another study, MMP was predicted by visual observation during the slim-tube test by Abdurrahman et al 17 MMP occurs when the oil is brighter than it was initially. This phenomenon occurs practically after the slope with a high recovery factor change to a smaller one.…”