| 摘要 |
The present invention refers to a system for extraction of geothermal energy and describes the method of filling and directing the borehole for effective thermal exchange between hot dry rocks and heating fluid in a closed coaxial pipe-in-pipe system. The set of coaxial circulation pipes (2, 4) is placed into the borehole (1), perpendicularly to the earth surface (15) in the cold layers of the earth (16). Approaching the hot layers of the earth (17), the borehole is directed at an angle of 30-90° against vertical direction. After drilling the borehole (1) the casing of the external pipe (2), is bonded with hot rock (17) by injection under the pressure of a material (6) of increased thermal conductivity, tightly filling the borehole (1 ) and void spaces around the external pipe (2), providing maximum thermal contact between the pipe (2) and the rock (17). The coaxial system of the pipes provides downgoing flow (7) from the surface to hot subterranean area for heating in the external pipe (2), and upgoing flow (8) through the internal pipe (4). Thermal energy is carried to the surface of the ground by heating liquid. After transferring to the consumer through the heat exchanger (10) the heating liquid is returned to the pipe (2) for recurrent heating. |
