Single-well heat exchange system and downhole enhanced heat exchange device of geothermal well

Abstract

The embodiment of the present application discloses a single-well heat exchange system and a downhole enhanced heat exchange device of a geothermal well. The first main pipe communicates with an inner pipe of the single-well heat exchange device, return water entering the inner pipe sequentially enters the first main pipe and the second main pipe, part of the return water directly flows back to a geothermal reservoir, and part of the return water enters an annulus between the inner pipe and an outer casing of the single-well heat exchange device through a through hole of the second main pipe. The part, located at a target reservoir, of the retractable heat exchange pipe is used for absorbing geothermal heat of the target reservoir and transmitting the geothermal heat to an fixed end of the retractable heat exchange pipe to heat the return water entering the first main pipe.