A data analysis of immiscible carbon dioxide injection applications for enhanced oil recovery based on an updated database

Abstract

Carbon dioxide (CO2) injection is an enhanced oil recovery technique used worldwide to increase oil recovery from hydrocarbon reservoirs. Immiscible CO2 injection involves injecting the CO2 into the reservoir at a pressure below which it will become miscible in the oil. Even though immiscible CO2 injection has been applied extensively, very little research has been conducted to provide a comprehensive understanding of the mechanism and the applications of immiscible CO2 injection. This research performs an in-depth data analysis is performed based on more than 200 experiments and 20 field tests from more than 40 researches to show the conditions at which immiscible CO2 injection has been applied and the most frequent application conditions. Histograms and boxplots have been generated for temperature, CO2 injection pressure, oil viscosity, molecular weight, and API gravity, CO2 solubility, and finally oil swelling to show the ranges and frequency of application for all these parameters. Finally, crossplots have been generated from the data to show the relation of pressure and temperature to CO2 solubility and oil swelling. The crossplots function to illustrate a relation between the variables and draws a conclusion as to what effect each parameter will have on the other.