JP6067173B1 - Geothermal exchanger and geothermal power generator - Google Patents

Abstract

Steam is efficiently extracted even when condensate is stored at the bottom of a pipe from which steam is extracted due to inherent factors in the initial stage of operation or fluctuations in pressure or temperature during operation. Provided is a geothermal exchanger and a geothermal power generation apparatus capable of performing the above. A geothermal exchanger is provided in the ground and supplied with water from the ground, and a first outer pipe disposed in the first outer pipe and disposed in the ground. The inner pipe 3 is provided. On the bottom of the first inner pipe 3, an on-off valve 6 for opening and closing the flow path of water from the first outer pipe 2 to the first inner pipe 3 is installed. It is connected with. The on-off valve 6 is closed when the water pressure and temperature at the bottom of the first outer pipe 2 are below the reference values, and when the water pressure and temperature at the bottom of the first outer pipe 2 exceeds the reference values. Open, high-pressure hot water is supplied to the spout 7 and a single-phase steam flow is generated. [Selection] Figure 1

Description

  The present invention relates to a geothermal exchanger and a geothermal power generation apparatus that can efficiently extract geothermal energy.

  Geothermal power generation using geothermal energy uses a high-temperature magma layer as a heat source and can be made into semi-permanent thermal energy and does not generate greenhouse gases in the process of power generation. In recent years, it has attracted attention as a fuel alternative. In addition, due to the accident at the nuclear power plant, Japan's energy policy, which relied heavily on nuclear power, has been reevaluated from the ground up, and expectations for the use of geothermal energy are increasing.

  Conventional geothermal power generation generates electricity by boring the geotropics and using natural pressure to extract natural steam and hot water that exist in the geotropics. Therefore, the extracted steam and hot water contain a large amount of sulfur and other impurities peculiar to the earth and tropics. This impurity becomes a scale and adheres to a heat well, piping, a turbine, or the like. If the scale adheres, the power generation output decreases over time, making long-term use difficult.

  In order to solve the problem due to this scale, Patent Literature 1 and Patent Literature 2 describe a geothermal exchanger that employs a method of sending water from the ground and taking it out as steam.

Japanese Patent No. 5731051 Japanese Patent No. 5791836

  What is described in Patent Document 1 is to boil under reduced pressure in a geothermal exchanger installed in the basement and take out a vapor single-phase flow, and what is described in Patent Document 2 is the heat loss of the extracted steam. Is a technology related to reducing the amount of heat, and all have a great advantage in that geothermal energy can be efficiently extracted.

  However, in the initial stage of operation, there is no pressure difference between the water injection pipe into which water is injected and the steam extraction pipe from which steam is taken out, so the water injection pipe and the steam extraction pipe rise at the same water level. Therefore, under this situation, steam may not be ejected to the steam take-out pipe, and the system may not operate.

  In addition, the amount of heat produced from the production well fluctuates due to delays in heat transfer due to conditions unique to the geotropics, fluctuations in the load on the generator, and the like. For this reason, even during operation, pressure and temperature change in the steam extraction pipe from which the steam is extracted due to these fluctuations, and therefore condensate may accumulate at the bottom of the steam extraction pipe. sell.

The present invention has been made in consideration of such circumstances, and condensate is stored at the bottom of the pipe from which steam is taken out due to inherent factors in the initial stage of operation and fluctuations in pressure and temperature during operation. It is an object of the present invention to provide a geothermal exchanger and a geothermal power generation device that can efficiently extract steam even when a situation occurs.

  In order to solve the above-described problems, a geothermal exchanger according to the present invention includes a first outer pipe provided in the ground and supplied with water from the ground, and a jet outlet disposed inside the first outer pipe. And the pressure in the first inner pipe is reduced to a pressure close to that required by the turbine, and heat is supplied from the earth to the water in the first outer pipe. This is a geothermal exchanger in which the high-pressure hot water generated in this way is converted into a steam single-phase flow in the first inner pipe existing in the ground through the jet outlet, and this steam single-phase flow is taken out to the ground. An opening / closing valve that opens and closes a flow path of water from the first outer tube to the first inner tube at the bottom of the first inner tube, and the jet outlet is connected to the opening / closing valve by a tube. The on-off valve is closed when the pressure and temperature of the water at the bottom of the first outer tube are below a reference value, Of if the pressure and temperature of the water of the outer tube bottom exceeds a reference value open, high-pressure hot water is supplied, characterized in that the vapor single-phase flow is generated to the spout.

  The on-off valve that opens and closes the flow path of the water from the first outer pipe to the first inner pipe at the bottom of the first inner pipe has a pressure at the first outer pipe side bottom that is equal to or lower than the pressure reference value. When the temperature of the water injected into the first outer pipe is below the temperature reference value, it is closed, and when the pressure and temperature of the water at the bottom of the first outer pipe exceeds the reference value, it is opened, Since high-pressure hot water is supplied to the jet outlet, the hot water reaches the jet outlet in a state where the conditions for steam generation are satisfied, and a single-phase steam flow is reliably generated in the first inner pipe. .

  In the geothermal exchanger of the present invention, a pressure regulating valve is connected to the first inner pipe, and the pressure regulating valve is opened at the initial stage of operation so that the pressure in the first inner pipe is reduced to an atmospheric pressure equivalent. The steam generation in the first inner pipe is promoted, and then the pressure regulating valve is gradually closed, and the steam valve connected to the first inner pipe is opened to take out the steam. it can.

  In the initial stage of operation, there is no pressure difference between the first outer pipe into which water is injected and the first inner pipe from which steam is taken out, so the first inner pipe and the first outer pipe rise at the same water level. However, it is easy for water to be stored in the first inner pipe, but the pressure in the first inner pipe is equivalent to atmospheric pressure when the pressure regulating valve connected to the first inner pipe opens in the initial stage of operation. The pressure is reduced to. Thereby, the steam generation in the first inner pipe is promoted by lowering the boiling temperature in the first inner pipe.

  In this manner, after sufficiently generating steam, the pressure regulating valve is gradually closed, and at the same time, the steam valve is opened to introduce steam into the turbine. In the initial stage of operation, both the temperature and pressure of the steam are low, and the generator directly connected to the turbine cannot achieve the rated power generation capacity. Therefore, it can be dealt with by adjusting the load.

  In the geothermal exchanger of the present invention, a water level sensor for detecting the water level of the stored water in the first inner pipe is installed, and when the water level of the stored water exceeds a reference water level, a signal from the water level sensor is used. The pressure regulating valve is opened, and the pressure in the first inner pipe is reduced to a pressure corresponding to atmospheric pressure, so that steam generation in the first inner pipe is promoted.

  The water level at the bottom of the first inner pipe is constantly measured, and when the stored water exceeds the reference water level, the pressure adjustment valve is opened and the inside of the first inner pipe is depressurized to the equivalent of atmospheric pressure. The water boils in a short time, and the stored water at the bottom of the first inner pipe can be drained.

  In the geothermal exchanger of the present invention, an insertion pipe formed by combining at least one first outer pipe and at least one first inner pipe is inserted into a plurality of production wells. The outlet of the first inner pipe is connected in parallel, the steam obtained by using each production well is collected in total, and a steam header for equalizing the pressure of the collected steam is provided, It can be set as the structure operated by removing the production well from which steam is not collected.

  By connecting a plurality of production wells in parallel, monitoring individual production wells at all times, and using the optimal production well, the operating rate of the entire production well can be improved. For production wells where steam is not collected, especially production wells where condensate is stored, if there are production wells with pressure regulating valves open to boil the condensate, connect multiple production wells. Thus, the production well in which the condensed water is stored can be removed from the operation, and steam can be supplied and covered from the other production wells in operation. Thereby, the process of condensed water can be performed, continuing a driving | operation, and the whole operation rate can be improved.

  Further, the geothermal exchanger of the present invention includes a second inner pipe provided in the ground and supplied with water from the ground, and a second outer pipe disposed outside the second inner pipe, The pressure in the second outer pipe is reduced to a pressure required by the turbine, and a partition that divides the upper area and the lower area of the second inner pipe, and the second inner pipe at the position of the partition. A pressure valve for opening and closing a water flow path from the upper region to the lower region of the pipe, and a pressure water jet is provided in the lower region of the second inner pipe, and the pressure valve When the water pressure at the position of the partition is below the reference value, it is closed, and when the water pressure at the partition position exceeds the reference value, it is opened and pressure water is supplied to the pressure water outlet, Compared to the second outer tube heated by the heat supplied from the tropics, the temperature is lower than that of the second outer tube. The pressure water in the second inner pipe is ejected from the pressure water outlet, converted into a vapor single-phase flow in the second outer pipe, and the vapor single-phase flow is taken out to the ground. .

  The pressure valve that opens and closes the water flow path from the upper region to the lower region of the second inner pipe is closed when the water pressure at the partition position is below the reference value, and the water at the partition position When the pressure exceeds the reference value, it opens and pressure water is supplied to the pressure water outlet, so only when a high pressure condition is met, it is injected from the pressure water outlet into the second outer tube as a shower. To do.

  The second outer pipe is heated by being supplied with heat from the earth, and the pressure water in the second inner pipe, which is lower in temperature than the second outer pipe, is supplied to the second outer pipe. By ejecting from the pressure water outlet, it is vaporized by heating boiling and converted into a vapor single-phase flow in the second outer tube, so that a vapor single-phase flow is reliably generated. Moreover, since it is heating boiling, both steam temperature and steam pressure can be maintained high. In this way, high-temperature steam can be generated from low-temperature and high-pressure water, and a single-phase steam flow can be effectively obtained with a simple apparatus configuration.

  In the geothermal exchanger of the present invention, a pressure regulating valve is connected to the second outer pipe, and the pressure regulating valve opens at the initial stage of operation so that the pressure in the second outer pipe is reduced to an atmospheric pressure equivalent. The steam generation in the second outer pipe is promoted, and then the pressure regulating valve is gradually closed and the steam valve connected to the second outer pipe is opened to take out the steam. it can.

  In the initial stage of operation, there is no pressure difference between the second inner pipe into which water is injected and the second outer pipe from which steam is taken out, so the second outer pipe and the second inner pipe rise at the same water level. However, there is a tendency for water to be stored in the second outer pipe, but when the pressure regulating valve connected to the second outer pipe opens in the initial stage of operation, the pressure in the second outer pipe is equivalent to atmospheric pressure. The pressure is reduced to. Thereby, the steam generation in the second outer tube is promoted by lowering the boiling temperature in the second outer tube.

  In this manner, after sufficiently generating steam, the pressure regulating valve is gradually closed, and at the same time, the steam valve is opened to introduce steam into the turbine. In the initial stage of operation, both the temperature and pressure of the steam are low, and the generator directly connected to the turbine cannot achieve the rated power generation capacity. Therefore, it can be dealt with by adjusting the load.

  In the geothermal exchanger of the present invention, a water level sensor that detects the water level of the stored water in the second outer pipe is installed, and when the water level of the stored water exceeds a reference water level, a signal from the water level sensor is used. The pressure regulating valve is opened, and the pressure in the second outer pipe is reduced to an atmospheric pressure equivalent to promote the generation of steam in the second outer pipe.

  When the water level at the bottom of the second outer pipe is constantly measured and the stored water exceeds the reference water level, the pressure adjustment valve is opened and the pressure in the second outer pipe is reduced to the equivalent of atmospheric pressure. The water boils in a short time, and the stored water at the bottom of the second outer pipe can be drained.

  In the geothermal exchanger of this invention, it can be set as the structure by which the heater which heats the water inject | poured into said 2nd inner pipe is provided on the ground.

  In the initial stage of operation, the turbine and condenser are not operating, and the temperature of the water injected into the second inner pipe is low, so the temperature of the water ejected from the outlet of the second inner pipe Since the steam is blown to the steam generating portion while the temperature is low, steam having a low temperature is produced, and the turbine output may be reduced.

  As a countermeasure, the temperature of the water injected into the second inner pipe is kept at a specified temperature by adopting a configuration in which a heater for heating the water injected into the second inner pipe is provided on the ground. The system can be activated safely. The heater can be appropriately installed between the outlet of the condenser and the inlet of the second inner pipe.

  In the geothermal exchanger of the present invention, an insertion pipe formed by combining at least one second outer pipe and at least one second inner pipe is inserted into a plurality of production wells. , The outlet of the second outer pipe is connected in parallel, the steam obtained using each production well is collected in total, and has a steam header that equalizes the pressure of the collected steam, It can be set as the structure operated by removing the production well from which steam is not collected.

  By connecting a plurality of production wells in parallel, monitoring individual production wells at all times, and using the optimal production well, the operating rate of the entire production well can be improved. For production wells where steam is not collected, especially production wells where condensate is stored, if there are production wells with pressure regulating valves open to boil the condensate, connect multiple production wells. Thus, the production well in which the condensed water is stored can be removed from the operation, and steam can be supplied and covered from the other production wells in operation. Thereby, the process of condensed water can be performed, continuing a driving | operation, and the whole operation rate can be improved.

The geothermal power generation apparatus of the present invention is characterized in that power is generated using the geothermal exchanger of the present invention.
In the geothermal exchanger of the present invention, condensed water is generated at the first inner tube bottom or the second outer tube bottom from which steam is taken out due to inherent factors in the initial operation and fluctuations in pressure and temperature during operation. Even when a situation of storage occurs, the steam can be efficiently taken out, so that efficient power generation can be performed.

  According to the present invention, even when a situation occurs in which condensed water is stored at the bottom of a pipe from which steam is taken out due to inherent factors in the initial stage of operation or fluctuations in pressure or temperature during operation, It is possible to realize a geothermal exchanger and a geothermal power generation apparatus that can take out the heat.

It is a figure which shows the geothermal exchanger and geothermal power generation apparatus which concern on 1st embodiment of this invention. In 1st embodiment of this invention, it is a figure which shows the condition where the condensed water is storing in the 1st inner pipe | tube. It is a figure which shows the geothermal exchanger and geothermal power generation apparatus which concern on 2nd embodiment of this invention. In 2nd embodiment of this invention, it is a figure which shows the condition where the condensed water is storing in the 2nd outer tube | pipe. It is a figure which shows the mechanism of the heating boiling in a steam saturation curve and 2nd embodiment of this invention.

Below, the geothermal exchanger and geothermal power generation apparatus of this invention are demonstrated based on the embodiment. FIG. 1 shows a geothermal exchanger and a geothermal power generation apparatus according to the first embodiment of the present invention.
In FIG. 1, a geothermal exchanger 1 includes a first outer pipe 2 provided in the ground and supplied with water from the ground, and a first outer pipe 2 disposed in the first outer pipe 2 and provided in the ground. The inner pipe 3 is provided. The water supplied to the first outer pipe 2 using a natural head is subjected to a pressure almost proportional to the depth from the ground near the bottom of the first outer pipe 2 to Is supplied and becomes high-temperature pressure water. In supplying water to the first outer pipe 2, a water supply pump 5 can be used. The first inner pipe 3 is connected to the turbine 13, and the pressure in the first inner pipe 3 is reduced to a pressure close to that required by the turbine 13.

  On the bottom of the first inner pipe 3, an on-off valve 6 for opening and closing the flow path of water from the first outer pipe 2 to the first inner pipe 3 is installed. It is connected with. The on-off valve 6 is closed when the water pressure and temperature at the bottom of the first outer pipe 2 are below the reference values, and when the water pressure and temperature at the bottom of the first outer pipe 2 exceeds the reference values. Opens and high-pressure hot water is supplied to the spout 7.

  Since the inside of the first inner pipe 3 is depressurized, the pressure difference is used to eject high-temperature pressure water from the jet outlet 7 into the first inner pipe 3 in a sprayed state, and the pressure required by the turbine 13. And it vaporizes using the pressure difference with the bottom part of the 1st outer pipe 2, and is converted into a vapor | steam single phase flow. The steam single-phase flow generated in the underground moves to the turbine 13 due to a pressure difference between the first inner pipe 3 and the turbine 13, and then expands in the turbine 13 to become power for turning the turbine 13. Electric power is generated by a generator by this power.

  Thereafter, the steam that has exited the turbine 13 is cooled by cooling water in the condenser 15 and returned to the water, and is supplied to the first outer pipe 2 again. Since the amount of water to be circulated is equal to the amount of steam required by the turbine 13, the amount of water to be circulated is very small. By repeating this process, geothermal heat is continuously taken out. If necessary, makeup water is replenished from the makeup water tank 16.

  The on-off valve 6 is a spring-type pressure valve, but as a simple method, a method of opening the spout 7 by operating the spout 7 with a wire from the ground may be used. In addition, as a method for measuring the pressure at the bottom of the first outer tube 2, a method for measuring the water level at the top of the first outer tube 2 can also be adopted.

  A pressure adjusting valve 9 and a steam generation valve 10 are connected to the first inner pipe 3, and the steam generation valve 10 is connected to a steam header 11. The steam header 11 is used when steam produced from a plurality of geothermal wells is collected and supplied to a single turbine 13, thereby making it possible to equalize the pressure.

  The steam generated in the geothermal exchanger 1 is sent to the steam header 11 through the steam generation valve 10. Connected to the steam header 11 is a steam generation valve 10 for sending steam generated by the geothermal exchanger 1 installed for other productivity to the steam header 11. The steam header 11 is connected to the turbine 13 via the steam valve 12.

  In the initial stage of operation, the pressure regulating valve 9 is opened, and the pressure in the first inner pipe 3 is reduced to the atmospheric pressure. In the initial stage of operation, there is no pressure difference between the first outer pipe 2 into which water is injected and the first inner pipe 3 from which steam is taken out, so the first inner pipe 3 and the first outer pipe 2 are Although the situation where water rises at the same water level and water is stored in the first inner pipe 3 is likely to occur, the pressure regulating valve 9 connected to the first inner pipe 3 opens in the initial stage of operation, so that the first The pressure in the inner tube 3 is reduced to an atmospheric pressure equivalent. Thereby, steam generation in the first inner pipe 3 is promoted by lowering the boiling temperature in the first inner pipe 3.

  In this way, after sufficient steam is generated, the pressure regulating valve 9 is gradually closed, and at the same time, the steam generation valve 10 and the steam valve 12 are opened to introduce the steam into the turbine 13. In the initial stage of operation, both the temperature and pressure of the steam are low, and the generator directly connected to the turbine 13 cannot achieve the rated power generation capacity. Therefore, it can be dealt with by adjusting the load.

  Further, as shown in FIG. 1, an insertion tube formed by combining at least one first outer tube 2 and at least one first inner tube 3 is inserted into a plurality of production wells. In addition, the outlets of the first inner pipe 3 can be connected in parallel so that the steam obtained using the respective production wells can be collected in total.

  By connecting a plurality of production wells in parallel, monitoring individual production wells at all times, and using the optimal production well, the operating rate of the entire production well can be improved. In particular, for a production well in which condensed water is stored, when there is a production well in which the pressure regulating valve 9 is open to boil the condensed water, the condensed water is stored by connecting a plurality of production wells. The existing production well can be removed from operation, and steam can be supplied and covered from other production wells in operation. Thereby, the process of condensed water can be performed, continuing a driving | operation, and the whole operation rate can be improved. When designing based on such premise, a numerical value obtained by subtracting one or two production wells from the number of production wells may be used as the output of the entire power plant at the time of planning, or a plan that matches the maintenance schedule may be used.

FIG. 2 shows a situation in which condensed water is stored in the first inner pipe.
The amount of heat produced from the production well fluctuates due to a delay in heat transfer due to the conditions specific to the geotropics 4 and load fluctuations of the generator. Therefore, even during operation, pressure and temperature change in the first inner pipe 3 from which the steam is taken out due to these fluctuations, and therefore the condensed water 14 is provided at the bottom of the first inner pipe 3. Can accumulate.

  In order to cope with such a situation, a water level sensor that detects the water level of the stored water 14 in the first inner pipe 3 is installed, and the water level of the stored water 14 exceeds the reference water level. The pressure adjustment valve 9 is opened by a signal from the water level sensor, and the pressure in the first inner pipe 3 is reduced to the atmospheric pressure. Thereby, generation | occurrence | production of the vapor | steam in the 1st inner pipe 3 is accelerated | stimulated, and the stored water 14 can be changed into a vapor | steam.

  Next, a geothermal exchanger and a geothermal power generation apparatus according to the second embodiment of the present invention will be described. FIG. 3 shows a geothermal exchanger and a geothermal power generation apparatus according to the second embodiment of the present invention.

  In FIG. 3, the geothermal exchanger 21 includes a second inner pipe 22 provided in the ground and supplied with water from the ground, and a second outer pipe 23 disposed outside the second inner pipe 22. I have. The pressure in the second outer pipe 23 is reduced to a pressure close to that required by the turbine 13, and a partition 24 that separates the upper region 22 a and the lower region 22 b of the second inner tube 22, and the position of the partition 24. And a pressure valve 25 for opening and closing the flow path of water from the upper region 22a to the lower region 22b of the second inner pipe 22. The water supplied to the second inner pipe 22 using a natural head is applied with a pressure approximately proportional to the depth from the ground near the bottom of the second inner pipe 22. In supplying water to the second inner pipe 22, the water supply pump 5 can be used.

  A pressure water outlet 26 is provided in the lower region 22 a of the second inner pipe 22. The pressure valve 25 that opens and closes the flow path of water from the upper region 22a to the lower region 22b of the second inner pipe 22 is closed when the water pressure at the position of the partition 24 is equal to or lower than a reference value. When the pressure of the water at the position 24 exceeds the reference value, it opens and high pressure water is supplied to the pressure water jet 26. For this reason, only when a high pressure condition is satisfied, the water is injected from the pressure water outlet 26 into the second outer tube 23 in a shower shape.

  The high pressure water in the second inner pipe 22, which is lower in temperature than the second outer pipe 23, is supplied to the pressure water outlet 26 with respect to the second outer pipe 23 that is heated by being supplied with heat from the earth tropics 4. And is converted into a vapor single-phase flow in the second outer pipe 23, and this vapor single-phase flow is taken out to the ground. The part where the second outer tube 23 comes into contact with the high-temperature tropics is subjected to processing that increases the heat conduction area, thereby increasing the heat conduction efficiency and sufficiently increasing the temperature of the second outer tube 23. Like that.

  The second outer tube 23 is heated by being supplied with heat from the earth's tropics 4 and is heated to a high temperature. The second outer tube 23 has a lower temperature than the second outer tube 23. When the pressure water in the second inner pipe 22 is ejected from the pressure water outlet 26, it is vaporized by heating and boiling, and is converted into a vapor single-phase flow in the second outer pipe 23. Since it is heating boiling, both steam temperature and steam pressure can be kept high. In this way, high-temperature steam can be generated from low-temperature and high-pressure water, and a single-phase steam flow can be effectively obtained with a simple apparatus configuration. As a more specific example, low-temperature high-pressure water that is approximately proportional to the depth of the well is generated by feeding low-temperature water at about 90 ° C. from the turbine 13 to the second inner pipe 22. It is ejected from the outlet 26 and heated and boiled by the second outer tube 23.

  The steam single-phase flow generated in the underground moves to the turbine 13 due to a pressure difference between the second outer pipe 23 and the turbine 13, and then expands in the turbine 13 to become power for turning the turbine 13. Electric power is generated by a generator by this power.

  Thereafter, the steam exiting from the turbine 13 is cooled by cooling water in the condenser 15 and returned to water, and is supplied to the second inner pipe 22 again. Since the amount of water to be circulated is equal to the amount of steam required by the turbine 13, the amount of water to be circulated is very small. By repeating this process, geothermal heat is continuously taken out. If necessary, makeup water is replenished from the makeup water tank 16.

  The pressure control valve 9 and the steam generation valve 10 are connected to the second outer pipe 23, and the steam generation valve 10 is connected to the steam header 11. The steam header 11 is used when steam produced from a plurality of geothermal wells is collected and supplied to a single turbine 13, thereby making it possible to equalize the pressure.

  The steam generated by the geothermal exchanger 21 is sent to the steam header 11 through the steam generation valve 10. Connected to the steam header 11 is a steam generation valve 10 that feeds steam generated by a geothermal exchanger 21 installed for other productivity to the steam header 11. The steam header 11 is connected to the turbine 13 via the steam valve 12.

  In the initial stage of operation, the pressure regulating valve 9 is opened, and the pressure in the second outer pipe 23 is reduced to the atmospheric pressure. In the initial stage of operation, there is no pressure difference between the second inner pipe 22 into which water is injected and the second outer pipe 23 from which steam is taken out, so the second outer pipe 23 and the second inner pipe 22 are Although the situation where water rises at the same water level and water is stored in the second outer pipe 23 is likely to occur, the pressure regulating valve 9 connected to the second outer pipe 23 opens in the initial stage of operation, so that the second The pressure in the outer tube 23 is reduced to an atmospheric pressure equivalent. Thereby, the steam generation in the second outer tube 23 is promoted by lowering the boiling temperature in the second outer tube 23.

  In this way, after sufficient steam is generated, the pressure regulating valve 9 is gradually closed, and at the same time, the steam generation valve 10 and the steam valve 12 are opened to introduce the steam into the turbine 13. In the initial stage of operation, both the temperature and pressure of the steam are low, and the generator directly connected to the turbine 13 cannot achieve the rated power generation capacity. Therefore, it can be dealt with by adjusting the load.

  Also, as shown in FIG. 3, an insertion tube formed by combining at least one second inner tube 22 and at least one second outer tube 23 is inserted into a plurality of production wells. In addition, the outlets of the second outer pipes 23 are connected in parallel so that the steam obtained using the respective production wells can be collected in total.

  By connecting a plurality of production wells in parallel, monitoring individual production wells at all times, and using the optimal production well, the operating rate of the entire production well can be improved. In particular, for a production well in which condensed water is stored, when there is a production well in which the pressure regulating valve 9 is open to boil the condensed water, the condensed water is stored by connecting a plurality of production wells. The existing production well can be removed from operation, and steam can be supplied and covered from other production wells in operation. Thereby, the process of condensed water can be performed, continuing a driving | operation, and the whole operation rate can be improved. When designing based on such premise, a numerical value obtained by subtracting one or two production wells from the number of production wells may be used as the output of the entire power plant at the time of planning, or a plan that matches the maintenance schedule may be used.

  It can be set as the structure by which the heater which heats the water inject | poured into the 2nd inner tube | pipe 22 is provided on the ground. Specifically, the heater can be appropriately installed between the outlet of the condenser 15 and the inlet of the second inner pipe 22, and may be attached to the makeup water tank 16.

  In the initial stage of operation, the turbine 13 and the condenser 15 are not operating, and the temperature of the water injected into the second inner pipe 22 is low, so that it is ejected from the outlet of the second inner pipe 22. Since the steam is sprayed on the steam generating portion while the temperature of the water is low, steam having a low temperature is produced, and the turbine output may be reduced.

  In order to prevent this situation from occurring, a heater for heating the water injected into the second inner tube 22 is provided on the ground so that the water is injected into the second inner tube 22. The water temperature can be kept at a specified temperature, and the system can be started up safely.

FIG. 4 shows a situation in which condensed water is stored in the second outer tube.
The amount of heat produced from the production well fluctuates due to a delay in heat transfer due to the conditions specific to the geotropics 4 and load fluctuations of the generator. Therefore, even during operation, the pressure and temperature change in the second outer pipe 23 from which the steam is taken out due to these fluctuations. Therefore, the condensed water 14 is placed at the bottom of the second outer pipe 23. Can accumulate.

  In order to cope with such a situation, when a water level sensor that detects the water level of the stored water 14 in the second outer pipe 23 is installed and the water level of the stored water 14 exceeds the reference water level, The pressure regulating valve 9 is opened by a signal from the water level sensor, and the pressure in the second outer pipe 23 is reduced to the atmospheric pressure. Thereby, generation | occurrence | production of the vapor | steam in the 2nd outer pipe | tube 23 is accelerated | stimulated, and the stored water 14 can be changed into a vapor | steam.

FIG. 5 shows a steam saturation curve and a mechanism of heating and boiling in the second embodiment of the present invention.
Assuming a case where an air layer of 200 m is formed on the upper part of the second inner pipe 22 into which water is injected, the pressure at the bottom of the second inner pipe 22 is as shown in Table 1. In the following table, the inner tube indicates the second inner tube 22 and the outer tube indicates the second outer tube 23.

  Table 2 shows the relationship between temperature and saturated vapor pressure.

  Based on the numerical values shown in Tables 1 and 2, the pressure and temperature at the bottom of the second inner tube 22, the temperature at the bottom of the second outer tube 23, and the temperature of the steam generated in the second outer tube 23 The pressure is shown in Table 3.

  As shown in Table 3, the second outer pipe 23 is supplied with heat from the earth tropics 4 and has a higher temperature than the second inner pipe 22. As shown in FIG. 5, pressure water having a temperature of 90 ° C. and a pressure of 2.94 MPa is ejected from the second inner tube 22 into the second outer tube 23 in a region of a temperature of 180 ° C. and a pressure of 0.476 MPa in a shower shape. Thus, steam at 150 ° C. is produced. Thereby, heating boiling is realized.

  In the geothermal exchanger and geothermal power generation apparatus of the present invention, there has been a situation in which condensed water is stored at the bottom of a pipe from which steam is taken out due to inherent factors in the initial stage of operation and fluctuations in pressure and temperature during operation. Sometimes, it can be widely used as a geothermal exchanger and a geothermal power generator that can efficiently extract steam.

DESCRIPTION OF SYMBOLS 1 Geothermal exchanger 2 1st outer pipe 3 1st inner pipe 4 Geotropics 5 Water supply pump 6 On-off valve 7 Spout 8 Pipe 9 Pressure regulation valve 10 Steam generation valve 11 Steam header 12 Steam valve 13 Turbine 14 Reservoir 15 Condenser 16 Supply water tank 21 Geothermal exchanger 22 Second inner pipe 22a Upper area 22b Lower area 23 Second outer pipe 24 Partition 25 Pressure valve 26 Pressure water outlet

Claims (10)

  A first outer pipe provided in the ground and supplied with water from the ground; and a first inner pipe disposed inside the first outer pipe and having a jet outlet; The pressure is reduced close to the pressure required by the turbine, and high-pressure hot water generated by supplying heat from the earth to the water in the first outer pipe is underground through the spout. A geothermal heat exchanger in which the steam single-phase flow is converted into a steam single-phase flow in the first inner pipe, and the steam single-phase flow is taken out to the ground, and the first outer pipe at the bottom of the first inner pipe An opening / closing valve for opening and closing a flow path of water from the first inner pipe to the first inner pipe, the jet outlet being connected to the on / off valve by a pipe, and the opening / closing valve at the bottom of the first outer pipe Closed when the water pressure and temperature are below the reference value, and when the water pressure and temperature at the bottom of the first outer tube exceeds the reference value Open, geothermal exchanger, characterized in that the high-pressure hot water is supplied to the spout by vapor single-phase flow is generated.   A pressure regulating valve is connected to the first inner pipe. In the initial stage of operation, the pressure regulating valve is opened, and the pressure in the first inner pipe is reduced to an atmospheric pressure equivalent. 2. The geothermal exchanger according to claim 1, wherein the generation of steam is promoted, and thereafter, the pressure regulating valve is gradually closed, and the steam valve connected to the first inner pipe is opened to take out steam.   A water level sensor that detects the water level of the stored water in the first inner pipe is installed, and when the water level of the stored water exceeds a reference water level, the pressure adjustment valve is opened by a signal from the water level sensor, 2. The geothermal exchanger according to claim 1, wherein the pressure in the first inner pipe is reduced to an atmospheric pressure equivalent to promote steam generation in the first inner pipe.   An insertion pipe formed by combining at least one first outer pipe and at least one first inner pipe is inserted into a plurality of production wells, and the outlet of the first inner pipe Are connected in parallel, and the steam obtained from each production well is collected in total, and has a steam header that equalizes the pressure of the collected steam. The geothermal exchanger according to any one of claims 1 to 3, wherein the geothermal exchanger is operated after being removed.   A second inner pipe provided in the ground and supplied with water from the ground, and a second outer pipe disposed outside the second inner pipe, and the pressure in the second outer pipe is: A pressure reducing pressure close to a pressure required by the turbine, a partition separating the upper region and the lower region of the second inner pipe, and water from the upper region to the lower region of the second inner pipe at the partition position A pressure valve that opens and closes the flow path of the second inner pipe, and a pressure water jet is provided in a lower region of the second inner pipe, and the pressure valve has a water pressure equal to or lower than a reference value at the partition position. In this case, the water is closed, and when the pressure of the water at the partition location exceeds a reference value, it is opened and pressure water is supplied to the pressure water outlet, and heat is supplied from the earth and heated. Pressure water in the second inner pipe that is cooler than the second outer pipe with respect to the second outer pipe Spouting from the pressure water ejecting port, is converted into the second vapor single-phase flow in the outer bulb of the geothermal exchanger, characterized in that the vapor single-phase flow is taken on the ground.   A pressure regulating valve is connected to the second outer pipe. In the initial stage of operation, the pressure regulating valve is opened, and the pressure in the second outer pipe is reduced to an atmospheric pressure equivalent. 6. The geothermal exchanger according to claim 5, wherein the generation of steam is promoted, and thereafter the pressure regulating valve is gradually closed and the steam valve connected to the second outer pipe is opened to take out steam.   A water level sensor that detects the water level of the stored water in the second outer pipe is installed, and when the water level of the stored water exceeds a reference water level, the pressure regulating valve is opened by a signal from the water level sensor, 6. The geothermal exchanger according to claim 5, wherein the pressure in the second outer pipe is reduced to an atmospheric pressure equivalent to promote steam generation in the second outer pipe.   The geothermal exchanger according to any one of claims 5 to 7, wherein a heater for heating water injected into the second inner pipe is provided on the ground.   An insertion pipe comprising a combination of at least one second outer pipe and at least one second inner pipe is inserted into a plurality of production wells, and the outlet of the second outer pipe Are connected in parallel, and the steam obtained from each production well is collected in total, and has a steam header that equalizes the pressure of the collected steam. The geothermal exchanger according to any one of claims 5 to 8, wherein the geothermal exchanger is operated after being removed.   A geothermal power generation apparatus that performs power generation using the geothermal exchanger according to any one of claims 1 to 9.

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