Removal of Water for Carbon Dioxide-Based EGS Operation

Abstract

CO2-based Engineered Geothermal Systems (EGS) have been explored from the perspectives of thermodynamic performance, in-reservoir chemical reactivity, and economic viability. Previous works have correctly noted the important role that initial water content in the geothermal reservoir will play in determining the viability of the concept, but have not examined reservoir water content from a quantitative basis. Here we assess the effect of water concentration limits for carbon dioxide-based EGS operation. We examine the relationship between drying time and reservoir characteristics such as connectivity, fluid volume, and fluid losses. This is expanded by calculation of total amount of carbon dioxide sequestered, and total amount of water produced.