CO2 injection for geothermal development associated with EGR and geological storage in depleted high-temperature gas reservoirs

Liang Zhang, Xin Li, Yin Zhang, Guodong Cui, Chunyang Tan, Shaoran Ren

Research output: Contribution to journalArticle

27 Scopus citations

Abstract

High-temperature gas reservoirs (HTGR) come with significant geothermal potentials. Supercritical CO2has been considered as one of the best heat transmission fluids for geothermal production. In this study, a novel concept technology of CO2-HTGR system has been proposed to develop the geothermal energy in the depleted high-temperature gas reservoirs through CO2injection associated with EGR and geological storage. CO2enhanced gas recovery (EGR) with pressure build-up should be conducted first to establish a CO2gas reservoir with a low methane content, then the hot CO2gas in the reservoir is produced for heat utilization and then injected back. Finally, the CO2gas reservoir is shut down for permanent geological storage. Reservoir numerical simulation has been conducted to study the fundamental processes of this concept technology including the establishment of a CO2gas reservoir through EGR and pure injection, and the heat mining performance of CO2gas cycling in the created reservoir. The simulation results indicate that a high injection-production ratio during CO2EGR can shorten the time of establishing a CO2gas reservoir. The purity of the established CO2gas reservoir has a significant influence on the heat mining performance of cyclic CO2gas. When the CO2purity in the gas reservoir is higher than 90%, the damage of the remaining methane to the heat mining rate of supercritical CO2can be controlled within 9.5%. The integrated process of CO2injection for geothermal development associated with EGR and geological storage is more attractive than the conventional CO2geothermal system and has a stronger on-site feasibility.

Original languageEnglish (US)
Pages (from-to)139-148
Number of pages10
JournalEnergy
Volume123
DOIs
StatePublished - Jan 1 2017

Keywords

  • Enhanced gas recovery
  • Geological storage
  • Geothermal development
  • Heat mining performance
  • High-temperature gas reservoir
  • Supercritical CO

Fingerprint Dive into the research topics of 'CO<sub>2</sub> injection for geothermal development associated with EGR and geological storage in depleted high-temperature gas reservoirs'. Together they form a unique fingerprint.

  • Cite this