Patent ID: 9714643
Date: 2017-07-25
CPC Classifications: F01K,F03G,F22B,F24T,F28D,F28F,Y02E

Claim:
1. A boiling-water geothermal heat exchanger comprising: a water injection pipe which is installed underground and to which water is supplied from the ground; and a steam extraction pipe which is installed underground so as to be in contact with the water injection pipe and has a plurality of ejection ports, in which a pressure inside the steam extraction pipe is reduced to the vicinity of a pressure required by a turbine, high-pressure hot water which is produced by supplying heat from a geothermal region to water inside the water injection pipe is changed to a single-phase flow of steam inside the steam extraction pipe present underground via the ejection ports, and the single-phase flow of steam is extracted on the ground, and in which a heat insulation portion is formed at a part which is in contact with a low-temperature region close to the ground surface and the heat insulation portion is such that the level of water supplied to the water injection pipe is lowered to form an air layer at an upper part of the water injection pipe.