Principal Component Analysis for the Opening of Underground Caves in Saline Rocks under Different Temperatures

Resumo

This study aims to analyze numerical data obtained during the process of opening of caves in saline
rocks considering the temperature variations. Over the years, saline caves have been widely used for the safe
storage of supercritical CO2, petroleum products and used as final destination of toxic waste such as radioactive
waste. The main motivation lies in the possibility of determining the variables from a statistical point of view that
most influence the opening process of these cavities. In fact, throughout the development of a cave, the variables
involved play a significant role in the success of the operation and also in determining its final behavior, it is
important to understand the way that they interact with each other and also with the fluids inside. In this work,
numerical simulations of the solution mining process for opening the cave under typical conditions of water
injection in a sodium chloride rock (using a finite difference code) are described and performed, after that, the
interpretation of the data obtained with the simulations is also done through a multivariate statistical tool (PCA).
The simulations show that the temperature and the flow directly influence the cave opening rate, in turn, the
statistical analysis of the data shows that the output variables have an almost similar contribution to the opening
of this cavern, moreover, it is possible to interpret the total variation of the data using only one component (PC1).