超临界二氧化碳用于地热开采的研究综述OA

The advantages of supercritical car-bon dioxide for geothermal exploitation are analyzed,the research progress of supercritical carbon dioxide applied to geothermal exploitation in hot dry rocks,deep saline aquifers and depleted oil and gas reservoirs is reviewed,the challenges faced are analyzed,and the future research trends are expected.With its unique thermo-physical properties,supercritical CO2 is more suitable for unconventional geothermal extraction than water.Dry hot rocks have the richest geothermal re-serves and belong to typical high-temperature geother-mal resources.Compared with water,using supercriti-cal CO2 as the working medium has higher heat recov-ery efficiency and can avoid geochemical reactions.Deep saline aquifers and depleted oil and gas reservoirs both belong to low to medium temperature geothermal resources,which are widely distributed and have natu-ral porous reservoir structures,and are suitable for com-bining CO2 geological storage and geothermal exploita-tion.Depleted oil and gas reservoirs have natural por-ous structure and well-developed trap structures,which can fully utilize existing well pattern and surface facili-ties during geothermal exploitation,saving investment and prolonging service life.For depleted gas reser-voirs,because natural gas extraction generally does not involve a water production process,which to some ex-tent avoids the occurrence of geochemical reactions,it very suitable to use supercritical CO2 for geothermal ex-traction.