Geothermal energy may be recovered through an underground well drilled to a depth approaching the earth's magma by circulation of injected heat transfer fluids flowing along separate parallel paths within closed loops extending into the well. One or more of the injected fluids may be conducted by a heat transfer portion of the loop establishing a lower heat absorbing zone within the well exposed to superheating conditions at ultra-deep depths. Circulation of the fluid within said heat transfer portion may be prolonged to efficiently absorb heat and heat loss may be minimized by heat exchange relationships between the parallel flow paths above the lower heat absorbing zone.
Apparatus for producing from a source of geothermal fluid that contains a mixture of high pressure steam, brine and noncondensable gases includes a heat exchanger for receiving geothermal fluid and transferring heat to water thereby vaporizing the same to produce steam. At least one power plant module is involved, the module having a steam turbine responsive to steam produced by the heat exchanger for producing work, a steam condenser containing an organic fluid and responsive to low pressure steam that exits the steam turbine for condensing the steam into a liquid and vaporizing the organic fluid. The module also contains an organic vapor turbine responsive to vaporizer organic fluid for producing work, and an organic vapor condenser responsive to the low pressure organic fluid that exits the organic vapor turbine condensing the organic vapor to a liquid that is returned to the steam condenser. The cooled geothermal fluid leaving the primary heat exchanger is conducted to a rejection well. Furthermore, an additional heat exchanger also can be provided, there being a first connection associated with both heat exchangers for selectively inserting the additional heat exchanger between the heat exchanger that receives the geothermal fluid and the injection well whereby the operation of the connection means may be coordinated with the operation of the power plant module.
A geothermal energy conversion system extracts heat from a heat source below the Earth's surface, which has a temperature above that of a fluid circulating through a closed system. A geothermal well and an enclosed well casing define a space that extends from ground level to the heat source. A heat exchanger is in thermal communication with the heat source, and a system of valves and at least one pump is in fluid communication, through the space within the well, with the heat exchanger. The system of pumps and valves regulates at least one of the flow rate or the pressure of the fluid so that the fluid vaporizes within the heat exchanger, the rate of vapor production in the heat exchanger is set at a predetermined value, and build-up of liquid within the heat exchanger is controlled.
An apparatus controls the evacuation of volcanic magma to prevent explosions. Magma evacuation is through a single evacuation tube that heats the magma flow within the tube to prevent stickiness of the magma in the tube. The heating may use small combustion chambers to heat steam, which in turn heats and stabilizes the magma flow. Stability is aided by central cooling, where needed, using water jets from nozzles located at the wall of the tube.
A geothermal power generation system having an input well extending from the surface into a hot rock strata and an output well spaced away from the input well extending from the surface into the hot rock strata. The input and output wells extend into the hot rock strata. A horizontal bore connects the two wells together. The bore is located in the hot rock strata and consists of a casing alone or a casing and a backfill between the casing and the hole, in order to prevent the water and steam flowing through the bore from coming into contact with either the hot rock strata or the aggressive water in the hot rock strata. Alternatively, the system may consist of only one vertical well and a horizontal bore extending into the hot rock strata and a pipe that returns the water into the horizontal bore. The water flowing through the horizontal bore changes to steam due to the heat of the hot rock strata and is discharged to a turbine that turns an electrical generator which in turn feeds power into an existing grid or other useful electrically operated device. This invention avoids the problem of controlling and/or treating the aggressive water in the hot rock strata thereby substantially reducing the cost of producing power from a geothermal resource.
A system for heating or cooling a wellhead, the system including a header in fluid communication via a pipe with a wellhead so that header heat transfer fluid is flowable from the header to the wellhead and back to the header, an earth heat exchange system with earth heat exchange fluid flowable therethrough to provide heat exchange between the earth heat exchange fluid and the earth, and the earth heat exchange fluid flowable in heat exchange relation to heat or cool the wellhead.
