JPH11223176A - Hot rock body power generating method and device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily adjust water injection amount to permeable layers by independently controlling the water injection amount to each permeable layer when water is sent to a plurality of peremable layers in the hot rock body from an injection well formed on the hot rock body, and recovering the obtained steam and hot water to utilize the same in the power generation. SOLUTION: An injection well 7 is formed on a hot rock body 5 as a water injection means 20, and the water is sent to a plurality of permeable layers 19 in the hot rock body 5 through the injection well 7 to be heated, whereby the steam and hot water are generated. Further, a production well 30 as a recovering means 31 is fomred on the hot rock body, so that the steam and hot water generated in the permeable layers 19 in which the water is injected by the injecting means 20 are recovered by this production well 30, and a power generating means 33 is driven by the recovered steam and hot water to generate the power. The water injecting means 20 comprises an outer pipe 21, a plurality of partition walls 22 for partitioning the inside of the outer pipe in the longitudinal direction, and the communication holes 24 for communicating the partitioned space 23 and the external of the outer pipe adjacent to each other, and the amount of the water jetted from the inner pipes 26 can be adjusted every inner pipe 26.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an injection well formed in a high-temperature rock body, in which water is fed into a permeable layer, heated and converted into steam or hot water, collected in a production well, and power is generated by the steam or hot water. The present invention relates to a hot rock power generation method to be performed and a hot rock power generation device using the same. More specifically, the present invention relates to an improvement in an injection method for injecting water into a permeable layer and an injection means, and a recovery method and an improvement in a recovery method for recovering steam and the like from the permeable layer.

[0002]

2. Description of the Related Art In order to perform hot rock power generation, about 200 to
An injection well and a production well are excavated at a depth of about 100 to 450 m toward an underground bedrock having a geothermal temperature of 400 ° C., and a permeable layer for flowing water between the injection well and the production well while heating the water is formed. Create many. Then, water is injected into the permeable layer at the injection well, and steam or hot water is taken out of the permeable layer at the production well and used for power generation.

[0005] In order to feed water into a large number of permeable layers at the injection well, an iron pipe 103 having a plurality of ejection holes 102 is installed inside the injection well 101 as shown in FIG. Each ejection hole 102 is formed at a position having a depth equivalent to that of the water permeable layer 104. When water is sent into the iron pipe 103 from the ground, water is spouted from each spout 102 and flows into the permeable layer 104 in the vicinity. Here, each ejection hole 10
The size of 2 is set so that the water injected into each permeable layer 104 has an optimal amount of water for uniformly extracting heat from the hot rock 105.

[0004] On the other hand, in a production well, for example, an iron pipe is installed inside to collect steam and hot water spouted from each permeable layer. The iron pipe for recovery is connected to a power generator and supplies steam to a steam turbine.

[0005]

However, in the hot rock power generation method described above, when the temperature of the rock body decreases due to the water flowing through the permeable layer 105 and the flow tunnel in the permeable layer 104 changes, the discharge hole is formed. Since the injection amount from 102 to the permeable layer 104 changes, the amount of heat extracted for each permeable layer 104 in the production well becomes uneven. If the amount of heat to be extracted becomes uneven in this manner, the temperature of steam or hot water obtained in the production well will vary and the power generation efficiency will be reduced. When the pressure changes, the iron tube 103 is pulled up and the ejection holes 10
The size of 2 is adjusted. However, since the adjustment work is complicated, the workability of the hot rock power generation is poor.

[0006] Further, in the production well, since steam and hot water from each permeable layer are collectively circulated through the recovery iron pipe, interference occurs due to a difference in hot water jet pressure between the permeable layers. For example, when the hot water spouting from the lower permeable layer is at a higher pressure than the hot water spouting from the upper permeable layer, if these hot waters are collected by a single iron tube, the hot water from the lower part is transferred to the upper permeable layer. It may flow in or prevent hot water from escaping from the upper permeable layer. When such hot water interference occurs, the efficiency of heat recovery from the high-temperature rock mass is reduced, so that it has been difficult to improve the power generation efficiency of the high-temperature rock power generation.

Accordingly, the present invention provides a high-temperature rock body that can easily adjust the amount of water injected into a permeable layer when a flow shaft in the permeable layer changes, and that prevents interference of hot water in each permeable layer in a production well. An object of the present invention is to provide a power generation method and a hot rock power generation device using the same.

[0008]

Means for Solving the Problems To achieve the above object, the invention according to claim 1 comprises a water injection step of sending water to a plurality of permeable layers in the hot rock with an injection well formed in the hot rock. In the heating step, water is heated while flowing through the permeable layer to become steam or hot water, and in the production well formed in the high-temperature rock body, the collecting step of collecting steam or hot water from the permeable layer, In a high-temperature rock power generation method including a power generation step of generating power by using collected steam or hot water, water is independently supplied to each permeable layer in the water injection step, and the amount of water injected is controlled for each permeable layer. .

Therefore, when the temperature of the rock body decreases due to the water flowing through the permeable layer and the flow tunnel in the permeable layer changes, the amount of water injected into each permeable layer is individually controlled to control the permeable layer. Can be constant. For this reason, the amount of heat extracted for each permeable layer in the production well can be equalized.

The invention according to claim 2 is a water injection step in which water is supplied to a plurality of permeable layers in the high-temperature rock by an injection well formed in the high-temperature rock, and the water is heated while flowing through the permeable layer. Heating process to generate steam and hot water, a recovery process to recover steam and hot water from the permeable layer in a production well formed in high-temperature rock, and power generation using the steam and hot water recovered in the recovery process In the high-temperature rock power generation method including a power generation step, steam and hot water are independently recovered for each permeable layer in the recovery step.

Therefore, even if there is a difference in hot water jet pressure between the permeable layers opened to the production well, they are not affected by each other, so that the amount of recovered steam and hot water can be increased. .

Further, the invention according to claim 3 is a water injection step in which water is sent to a plurality of permeable layers in the hot rock with an injection well formed in the hot rock, and the water is heated while flowing through the permeable bed. Heating process to generate steam and hot water, a recovery process to recover steam and hot water from the permeable layer in a production well formed in high-temperature rock, and power generation using the steam and hot water recovered in the recovery process In the high-temperature rock power generation method including the power generation step, water is independently supplied to each permeable layer in the water injection step, the amount of water injected is controlled for each permeable layer, and steam is independently generated for each permeable layer in the recovery step. And to recover hot water.

Therefore, when the temperature of the rock body decreases due to the water flowing through the permeable layer and the flow tunnel in the permeable layer changes, the amount of water injected into each permeable layer is individually controlled to control the permeable layer. Can be constant. For this reason, the amount of heat extracted for each permeable layer in the production well can be equalized. Further, even if there is a difference in hot water ejection pressure between the permeable layers opened to the production well, they are not affected by each other, so that the amount of recovered steam and hot water can be increased.

[0014] On the other hand, in the invention according to claim 4, water is supplied to a plurality of permeable layers in the high-temperature rock body by an injection well formed in the high-temperature rock body and heated to produce steam or hot water, In a high-temperature rock power generation apparatus, there is provided a recovery means for recovering steam and hot water from a permeable layer in a production well formed in a high-temperature rock body, and a power generation means for generating power using the steam and hot water recovered by the recovery means. The water injection means includes an outer pipe, a plurality of partition walls perpendicular to the longitudinal direction that partition the inside of the outer pipe in the longitudinal direction, and a communication hole that communicates a partition space between adjacent partition walls and the outside of the outer pipe. A ring-shaped water-blocking projection formed on the outer periphery of a portion where the partition wall of the outer pipe is formed; and a downstream end opened in each of the partition spaces accommodated in the outer pipe and an upstream side attached to a water pump. Adjust the number of inner pipes and the amount of water spouted from each inner pipe for each inner pipe. So that a control means.

Therefore, when water is injected into the permeable layer of the water injection well, water is supplied from the water supply pump to each of the inner pipes and jetted into the partition space. The water flows out of the outer space through the communication hole from the partition space. This water fills the space between two adjacent water-impervious projections and then enters the permeable layer. Then, when the temperature of the rock body decreases due to the water flowing through the permeable layer and the flow channel in the permeable layer changes, the amount of water spouted from each inner pipe is individually adjusted by the control means. For this reason, the injection amount from each inner pipe to the permeable layer can be made constant. This makes it possible to equalize the amount of heat extracted for each permeable layer in the production well.

In addition, the water jetted from the communication hole is prevented from leaking through the space between the outer tube and the wall by the water-blocking projections. It is possible to reduce the amount of water to be surely injected.

Further, the invention according to claim 5 is a water injection means for feeding water to a plurality of permeable layers in the high-temperature rock body by using an injection well formed in the high-temperature rock body and heating the water to form steam or hot water; In a high-temperature rock power generation apparatus, there is provided a recovery means for recovering steam and hot water from a permeable layer in a production well formed in a high-temperature rock body, and a power generation means for generating power using the steam and hot water recovered by the recovery means. The recovery means includes an outer pipe, a plurality of partition walls perpendicular to the longitudinal direction that partition the inside of the outer pipe in the longitudinal direction, and a communication hole that communicates a partition space between adjacent partition walls and the outside of the outer pipe. A ring-shaped water-impervious projection formed on the outer periphery of the part where the partition wall of the outer pipe is formed, and an upstream end opened in each of the partition spaces accommodated in the outer pipe and the downstream side connected to the power generation means. And a plurality of inner tubes.

Therefore, when recovering steam or the like from the permeable layer opened to the production well, the steam or the like spouted from each permeable layer fills between two adjacent water-impervious projections and passes through the communication hole. Get inside the partition space. Further, steam or the like enters the inner pipe from the partition space and is supplied to the power generation means. For this reason, it is filled between two different water-impervious projections for each water-permeable layer and supplied directly to the power generation means. Therefore, even if there is a difference in the pressure of hot water jetted between the water-permeable layers, they affect each other. Without receiving it, the amount of recovered steam or hot water can be increased.

Further, the invention according to claim 6 is a water injection means for injecting water into a plurality of permeable layers in the high-temperature rock body by using an injection well formed in the high-temperature rock body and heating it to produce steam or hot water; In a high-temperature rock power generation apparatus, there is provided a recovery means for recovering steam and hot water from a permeable layer in a production well formed in a high-temperature rock body, and a power generation means for generating power using the steam and hot water recovered by the recovery means. The water injection means includes an outer pipe, a plurality of partition walls perpendicular to the longitudinal direction that partition the inside of the outer pipe in the longitudinal direction, and a communication hole that communicates a partition space between adjacent partition walls and the outside of the outer pipe. A ring-shaped water-blocking projection formed on the outer periphery of a portion where the partition wall of the outer pipe is formed; and a downstream end opened in each of the partition spaces accommodated in the outer pipe and an upstream side attached to a water pump. Adjust the number of inner pipes and the amount of water spouted from each inner pipe for each inner pipe. Control means, and the collecting means, the outer pipe, a plurality of partition walls perpendicular to the longitudinal direction that partition the inside of the outer pipe in the longitudinal direction, a partition space between adjacent partition walls and the outside of the outer pipe. And a ring-shaped water-impervious projection formed on the outer periphery of the part where the partition wall of the outer pipe is formed,
An upstream end is opened in each of the partition spaces accommodated in the outer tube, and a plurality of inner tubes connected to the power generation means on the downstream side are provided.

Therefore, when water is injected into the permeable layer of the injection well, water is supplied from the water supply pump to each of the inner pipes and jetted into the partition space. The water flows out of the outer space through the communication hole from the partition space. This water fills the space between two adjacent water-impervious projections and then enters the permeable layer. Then, when the temperature of the rock body decreases due to the water flowing through the permeable layer and the flow channel in the permeable layer changes, the amount of water spouted from each inner pipe is individually adjusted by the control means. For this reason, the injection amount from each inner pipe to the permeable layer can be made constant. This makes it possible to equalize the amount of heat extracted for each permeable layer in the production well. In addition, since the water jetted from the communication hole is prevented from leaking through the outer tube and the anti-wall by the water-blocking projection, the pressure loss when water is injected into each permeable layer is reduced. Reliable water injection can be performed.

When recovering steam or the like from the permeable layer opened to the production well, steam or the like spouted from each permeable layer fills between two adjacent water-impervious projections and passes through the communication hole. Get inside the partition space. Further, steam or the like enters the inner pipe from the partition space and is supplied to the power generation means. For this reason, it is filled between two different water-impervious projections for each water-permeable layer and supplied directly to the power generation means. Therefore, even if there is a difference in the pressure of hot water jetted between the water-permeable layers, they affect each other. Without receiving it, the amount of recovered steam or hot water can be increased.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The configuration of the present invention will be described below in detail based on an example of an embodiment shown in the drawings. As shown in FIG. 1, the hot rock power generation device 34 of the present embodiment sends water to the plurality of permeable layers 19 in the hot rock 5 by using the injection well 7 formed in the hot rock 5 and heats the water. A water injection means 20 for producing steam or hot water, a recovery means 31 for recovering steam or hot water from the permeable layer 19 in a production well 30 formed in the high-temperature rock 5,
And a power generating means 32 for generating power using the steam or hot water collected by the collecting means 31.

The water injection means 20 includes an outer pipe 21, a plurality of partition walls 22 that partition the inside of the outer pipe 21 in the longitudinal direction, and a plurality of partition walls 22 perpendicular to the longitudinal direction, and a partition space 2 between adjacent partition walls 22.
A communication hole 24 for communicating the outer tube 3 with the outside of the outer tube 21;
A ring-shaped water-blocking projection 25 formed on the outer periphery of the portion where the first partition wall 22 is formed;
3, a plurality of inner pipes 26 each having a downstream end open and an upstream side attached to the water pump 9;
And control means 33 for adjusting the amount of water spouting from each inner tube 26. The water injection means 20 is suspended from the ground by the tower 6 and is supported inside the injection well 7.

The water supply pump 9 is mounted on the upstream side of the inner pipe 26. The water pump 9 is installed on the ground. The water pump 9 is connected to the reservoir 8 by a connecting pipe 28. Then, the water pump 9 supplies the water in the reservoir 8 to each of the inner pipes 26. At this time, the control means 33 controls the inner pipe 2
The amount of water spouted from 6 can be adjusted for each inner tube 26. For this reason, the amount injected into each permeable layer 19 can be adjusted separately for each corresponding inner pipe 26. Control means 3
Examples of the type 3 include a type using a flow control valve and a type using a pump capable of individually adjusting the pump output for each inner pipe 26.

The inner pipe 26 extends through the partition wall 22. This penetrating part is sealed. Therefore, each partition space 23 is communicated with the outside only by the communication hole 24. As shown in FIGS. 1 and 2, three inner pipes 26 are provided at different downstream end portions. For this reason,
Water can be independently injected into the permeable layer 19 at three different depths of the injection well 7. In this embodiment, the inner pipe 26 is 3
The number of books is not limited to two, but may be two or four or more. Even in these cases, water injection can be performed for each permeable layer 19 at a plurality of locations at different depths of the injection well 7.

The outer tube 21 and the injection well 7 have a circular cross section. The lower end of the outer tube 21 is opened to form an opening 21a. The outer tube 21 is formed as a long tube by joining short tubes. That is, when the water injection means 20 is installed in the injection well 7, a short outer pipe 21 is first suspended from the tower 6, and short pipes are successively connected and extended downward. As the connection method here, existing or new connection means such as screwing or welding can be used, but it is preferable to use screwing in consideration of ease of assembly and removal.

The short pipe at the portion where the downstream end of the inner pipe 26 opens has a communication hole 24. Communication hole 24
Is a size and quantity that does not significantly reduce the strength of the outer tube 21. Further, the arrangement of the communication holes 24 can be, for example, a staggered shape. Further, partition walls 22 are formed at the upper and lower ends of the short pipe. Thereby, the partition wall 22 can be easily attached.

The outer diameter of the outer tube 21 is smaller than the inner diameter of the injection well 7 by about 20 mm. That is, the outer tube 21
Has an interval of about 10 mm between the outer peripheral surface and the pit wall 7a. For this reason, the water spouted from the communication hole 24 causes the
Since the shaft flowing between the inner pipe a and the outer peripheral surface of the outer pipe 21 is large, water leakage hardly occurs upward. Here, in order to prevent water leakage to the upper side, the formation depth of the communication hole 24 at the uppermost position is about 1
It is preferably at least 00 m. Further, since there is little leakage of water spouted from the communication hole 24, the loss of water pressure pressing the pit wall 7a can be reduced. In the present embodiment, the outer tube 2
1, the gap between the outer peripheral surface and the pit wall 7a is about 10 mm, and the formation depth of the communication hole 24 at the uppermost position is about 100 m or more. However, the present invention is not limited to this. It can be set within a range in which upward leakage of water can be prevented based on a shaft or the like when flowing between the shaft 21 and the pit wall 7a.

As the inner pipe 26 and the outer pipe 21, it is preferable to use an iron pipe in consideration of the temperature condition of the high-temperature rock 5.

Further, the water-blocking projection 25 protrudes from the outer peripheral surface of the outer tube 21 by about 5 mm. That is, there is a gap of about 5 mm between the water-blocking projection 25 and the pit wall 7a. With such a gap, the water jetted from the communication hole 24 hardly leaks from between the impermeable protrusion 25 and the pit wall 7a.
For this reason, there is little leakage of water spouted from the communication hole 24, and it is possible to reduce the loss of water pressure that presses the pit wall 7a. Moreover, when installing the water injection means 20 in the injection well 7,
The water-blocking projection 25 can be easily inserted without making contact with the pit wall 7a. In the present embodiment, the gap between the impermeable protrusion 25 and the pit wall 7a is set to about 5 mm. However, the present invention is not limited to this. It can be set within a range in which water leakage can be prevented based on a shaft or the like at the time.

On the other hand, the recovery means 31 comprises an outer tube 21, a plurality of partition walls 22 which vertically partition the inside of the outer tube 21, and a partition space 23 between adjacent partition walls 22.
A communication hole 24 that communicates with the outside of the outer tube 21;
Ring-shaped water-impervious projections 25 formed on the outer periphery of the portion where the partition wall 22 is formed, and the partition space 23 accommodated in the outer tube 21.
Has a plurality of inner pipes 26 each of which has an upstream end open and a downstream side connected to the power generation means 32.

Here, the outer pipe 21, the partition wall 22, the communication hole 24, the water-blocking projection 25, and the inner pipe 26 used for the collecting means 31 have the same configuration as that used for the water injection means 20. The detailed description is omitted with the same reference numerals.

The power generation means 32 is provided in the inner pipe 26 of the recovery means 31.
For example, a steam turbine is driven by steam and hot water obtained from the above to generate power. Then, the used steam is condensed and returned to the reservoir 8. This power generation means 3
2 is not a characteristic configuration of the present invention, and may be any known or new device that generates power using steam and hot water.

The collecting means 31 is suspended from the ground by the tower 6 and is supported inside the production well 30. The installation depth of the collecting means 31 is such that the permeable layer 19 opening inside the production well 30 and the communication hole 24 face each other. As a result, the steam and the hot water spouted from each permeable layer 19 are filled between the separate water-blocking projections 25 and 25 and enter the partition space 23 from the communication hole 24. Then, the steam and the hot water are supplied from the separate partition spaces 23 to the power generation means 32 through the respective inner pipes 26.

The procedure for installing the above-described hot rock power generator 34 will be described below.

In order to form the injection well 7, a borehole 7 ′ is excavated in the hot rock 5. This excavation method may be any existing or new method. For example, excavation is performed according to the following procedure.

As shown in FIGS. 3 and 4, the excavator 1 here has an outer pipe 1 through at least three inner pipes 2 to 4.
5 is inserted into the borehole 7 ′, a high-pressure liquid is supplied to the first inner pipe 2, and a gas is supplied to the second inner pipe 3. The downhole motor 12 composed of a motor is driven by liquid to
3, while the drill hole 14 is discharged through the third inner pipe 4 and the liquid is collected by the pressure of the liquid and the buoyancy of the gas that have driven the downhole motor 12.
The front end of the first inner pipe 2 is connected to a hydraulic pressure supply port 12 a of a downhole motor 12, and the rear end is connected to a water pump 9 for pumping water in a reservoir 8. The tip of the second inner pipe 3 is connected to a position near the tip of the third inner pipe 4, and the rear end is connected to the compressor 10. Further, the distal end of the third inner pipe 4 opens behind the downhole motor 12, and the rear end opens to the reservoir 8. The water outlet 12b of the downhole motor 12 is formed between the bit 13 and the wellhead wall 7a.

The outer tube 15, the first inner tube 2, the second inner tube 3, and the third inner tube 4 are preferably made of iron in consideration of the temperature conditions to be used. However, it is not necessary to use an iron pipe, and when the operating temperature is low, a pipe made of plastic or the like may be used. Further, it is not always necessary to connect the tip of the second inner pipe 3 to the vicinity of the tip of the third inner pipe 4, and a position where the excavation slide 14 is raised and compressed air can be supplied when the pressure of the high-pressure water is weakened to some extent. Alternatively, the tip of the second inner tube 3 may be connected.

Then, the excavator 1 is inserted into the boring pit 7 'by using the tower 6 assembled on the ground. Next, the water in the reservoir 8 is pressurized by the water pump 9 and supplied to the first water pipe 2, and the high-pressure water drives the downhole motor 12 to rotate the bit 13 at high speed.
The bit 13 that rotates at a high speed excavates the rock 5, and the generated excavation waste 14 accumulates in the surroundings. On the other hand, the high-pressure water that has driven the downhole motor 12 blows out from the water discharge port 12b and flows between the bit 13 and the wellhead wall 7a.
The bit 13 heated by friction with a is cooled, and the excavation waste 14 is flushed behind the bit 13. Then, the flow of the high-pressure water and the drilling waste 14 flows into the third inner pipe 4.

On the other hand, in the second inner pipe 3, the compressor 1
Compressed air is supplied from zero. The compressed air is supplied to the third inner pipe 4
The buoyancy of the excavation waste 14 and the high-pressure water that rises in the third inner pipe 4 give rise to the buoyancy. With the help of this buoyancy, the drilling waste 14 and the high-pressure water rise in the third inner pipe 4 and are discharged into the reservoir 8 on the ground. That is, the drilling waste 14 is discharged from the borehole 7 ′ through the third inner pipe 4 and the high-pressure water is recovered. Bit 13 is rock 5
By lowering bit 13 as you excavate
Drill the boring pit 7 '. Then, when the excavator is dug down to a required depth, the excavator is stopped, and the excavator 1 is raised using the tower 6 assembled on the ground so as to be taken out of the boring pit 7 '.

In this excavation method, compressed air is supplied from the first inner pipe 2 to the third inner pipe 4 to generate buoyancy to assist the excavation slip 14 and the high-pressure water to rise. It is possible to easily discharge the excavation waste 14 and recover the high-pressure water without using a large amount of water. Further, the discharge of the drilling waste 14 and the recovery of the high-pressure water are performed by the dedicated third inner pipe 4, and the inner surface of the third inner pipe 4 is formed by a boring hole 7 ′.
The excavation waste 14 and the high-pressure water flow are small compared to the wellhead wall 7a, so that the discharge of the excavation waste 14 and the recovery of the high-pressure water are facilitated. Furthermore, even if a rock or the like, which serves as an escape path for water, exists in the rock body 5, the discharge of the excavation waste 14 and the recovery of high-pressure water can be reliably performed through the third inner pipe 4.

Next, a permeable layer 19 is formed inside the rock 5 from the formed boring pit 7 '. This creation is performed in the following procedure, for example, by using a permeable layer creating apparatus that also serves as the water injection means 20. However, the permeable layer forming device for forming the permeable layer 19 is not limited to the device that also serves as the water injection means 20 as in the present embodiment, and a dedicated device may be used.

The permeable layer forming device 20 is lowered and inserted by using the tower 6. Then, after the permeable layer forming device 20 reaches a predetermined depth and stops descending, the upstream end of each inner pipe 26 is connected to the water pump 9. After the connection, the water pump 9 is driven to pressurize the water in the reservoir 8 and simultaneously supply the water to each of the inner pipes 26.

At the downstream end of each of the inner tubes 26, high-pressure water spouts into the partition space 23. And the water is the partition space 23
When it is stored from the bottom of the container and reaches the communication hole 24, the communication hole 24
From the outer tube 21. At the lowermost part of the outer tube 21, the opening 21 a
Erupts from

The high-pressure water spouted from the communication hole 24 is stored between the water-blocking projections 25, 25 provided above and below the communication hole 24, the pit wall 7 a, and the outer surface of the outer pipe 21. Then, when the air is expelled from this space and completely filled, the high-pressure water presses the wellhead wall 7a. At the lowermost part of the outer tube 21, the high-pressure water is stored between the water-blocking projection 25 at the lowest position and the pit wall 7a, and drives out the air to completely fill the pit wall 7.
Press a.

If a large number of narrow joints have already been formed on the pit wall 7a, high pressure water is applied to the pit wall 7a so that some joints spread while narrowing other joints, thereby reducing water. To form the permeable layer 19. In addition, pit wall 7a
When the joint is not formed, high pressure water is applied to the pit wall 7a, a new crack is generated, and water is drawn in to form the permeable layer 19. At this time, the amount of water flowing into the permeable layer 19 is theoretically the cube of the width of the fracture (actually 2
To the power).

Then, a control means 33 is attached to the upstream part of the inner pipe 26 of the permeable layer forming apparatus, and
Set to 0. In this embodiment, since the permeable formation device is also used as the water injection means 20 of the hot rock power generation device 34, it is not necessary to remove the permeable formation device from the injection well 7 after the formation of the permeable layer 19. For this reason, it is possible to reduce the cost of installing the hot rock power generation device 34 and shorten the construction period.

On the other hand, production wells 30 for collecting steam and hot water inside the permeable layer 19 are formed at several places in the area where the permeable layer 19 is formed. The excavation procedure of the production well 30 is the same as that of the injection well 7 described above, and the description is omitted. Then, the collecting means 31 is installed in the excavated production well 30. The procedure for installing the recovery means 31 in the production well 30 is the same as that of the water injection means 20 (permeable layer forming apparatus) for the injection well 7 described above, and therefore the description is omitted. Further, the downstream side of the inner pipe 26 of the collection means 31 installed in the production well 30 is connected to the power generation means 32.

The procedure for power generation by the hot rock power generator 34 will be described below.

In this hot rock power generation method, a water injection step of sending water to a plurality of permeable layers 19 in the hot rock 5 through the injection well 7 formed in the hot rock 5, and water flowing through the permeable bed 19. A heating process of forming steam or hot water while heating
And a power generation step of generating power using the steam and hot water collected in the recovery step.

In the water injection step, the water pump 9 is driven to supply the water in the reservoir 8 to each of the inner pipes 26 at the same time. Each inner pipe 26
At the downstream end, water spouts into the partition space 23.
When the water is stored from the bottom of the partition space 23 and reaches the communication hole 24, the water is ejected from the communication hole 24 to the outside of the outer tube 21. Further, at the lowermost part of the outer tube 21, water is spouted from the opening 21a without storing water in the partition space 23.

The water spouted from the communication hole 24 is separated from the water blocking projections 25 provided above and below the communication hole 24 and the pit wall 7a.
And the outer surface of the outer tube 21. Then, water flows into the permeable layer 19 from this space. In addition, the outer tube 21
At the lowest part of the water, the water impinges at the lowest position and the
a and flows into the permeable layer 19. At this time, the water spouted from the communication hole 24 is transmitted between the outer tube 21 and the anti-wall 7a and leaks out.
5, the pressure loss at the time of injecting water into each permeable layer 19 can be reduced and reliable water injection can be performed.

The water injected into the permeable layer 19 is heated by the high-temperature rock 5 in the heating step to become hot water and steam, and reaches one of the production wells 30. Here, when the temperature of the rock body decreases due to the water flowing through the water permeable layer 19 and the flow shaft in the water permeable layer 19 changes, the amount of water spouted from each inner pipe 26 is individually adjusted by the control means 33. The injection amount from each inner tube 26 to the permeable layer 19 is made constant. Thereby, the amount of heat extracted for each permeable layer 19 in the production well 30 can be equalized, so that the power generation efficiency can be improved. Moreover, since the water injection amount can be changed for each permeable layer 19 without taking out the water injection means 20 from the injection well, the work of power generation can be improved without the need for complicated work for changing the water injection amount.

In the recovery step, the permeable layer 19 is formed at each production well 30.
The steam and hot water from the water are impermeable projections 25 and 2 of the recovery means 31.
5 and between the pit wall 7a and the outer surface of the outer tube 21. Then, the steam and the hot water pass through the communication hole 24 from this space and enter the partition space 23. Further, the steam and the hot water are supplied from each partition space 23 to the power generation means 32 via the inner pipe 26. For this reason, since it fills between the two water-impervious projections 25 different for each water-permeable layer 19 and is directly supplied to the power generation means 32, there is a difference in the pressure of hot water jetted between the water-permeable layers 19. Are not affected by each other, and the amount of recovered steam or hot water can be increased. Thereby, the efficiency of heat recovery from the high-temperature rock 5 can be improved, so that the power generation efficiency can be improved.

In the power generation step, the power generation means 32 operates the steam turbine using the supplied steam to generate power.
The condensed steam is returned to the reservoir 8.

The above embodiment is an example of a preferred embodiment of the present invention, but the present invention is not limited to this, and various modifications can be made without departing from the spirit of the present invention. For example, in the present embodiment, a device that serves both as the water permeable layer forming device and the water injection means 20 is used, but the present invention is not limited to this, and these devices may be separate devices. Again,
By individually adjusting the amount of water spouted from each inner pipe 26 by the control means 33, the amount of heat extracted for each permeable layer 19 in the production well 30 can be made uniform, and each water can be extracted without taking out the water injection means 20 from the water injection well. The amount of water injected can be changed for each permeable layer 19.

In the present embodiment, both the water injection means 20 and the recovery means 31 are provided, but only one of them may be provided. In this case, even if only the water injection means 20 is provided, the amount of heat extracted for each permeable layer 19 in the production well 7 can be equalized, and a complicated operation for changing the amount of injected water can be eliminated. The pressure loss at the time of pouring water into the layer 19 can be reduced to perform reliable pouring.
On the other hand, even if only the recovery unit 31 is provided, the efficiency of heat recovery from the high-temperature rock body can be improved by increasing the recovery amount of steam or hot water, so that the power generation efficiency can be improved.

[0058]

As is apparent from the above description, according to the hot rock power generation method of the first aspect, water is independently supplied to each permeable layer in the water injection step, and the amount of water injected is controlled for each permeable layer. When the rock temperature decreases due to the water flowing through the permeable layer and the flow through the permeable layer changes, the amount of water injected into each permeable layer is individually controlled to inject into the permeable layer. The amount can be constant. For this reason, since the amount of heat extracted for each permeable layer in the production well can be equalized, the power generation efficiency can be improved. In addition, since the water injection amount can be changed for each permeable layer without taking out the water injection means from the injection well, complicated work for changing the water injection amount is not required, and the workability of power generation can be improved.

According to the high-temperature rock power generation method of the second aspect, since steam and hot water are independently collected for each permeable layer in the recovery step, heat is generated between the permeable layers opened to the production well. Even if there is a difference between the pressures at which water is jetted out, they are not affected by each other. For this reason, the recovery amount of steam or hot water can be increased. Thereby, the efficiency of heat recovery from the high-temperature rock body can be improved, so that the power generation efficiency can be improved.

Further, according to the high-temperature rock power generation method of the third aspect, when the rock temperature is lowered by the water flowing through the water permeable layer and the flow tunnel in the water permeable layer changes, each water permeable layer is connected. On the other hand, by individually controlling the water injection amount, the injection amount into the permeable layer can be made constant. For this reason, since the amount of heat extracted for each permeable layer in the production well can be equalized, the power generation efficiency can be improved. In addition, since the water injection amount can be changed for each permeable layer without taking out the water injection means from the injection well, complicated work for changing the water injection amount is not required, and the workability of power generation can be improved. Also, even if there is a difference in hot water jetting pressure between the permeable layers that open to the production well, they are not affected by each other. For this reason, the recovery amount of steam or hot water can be increased. Thereby, the efficiency of heat recovery from the high-temperature rock body can be improved, so that the power generation efficiency can be improved.

On the other hand, according to the high-temperature rock power generation device of the present invention, when the temperature of the rock body decreases due to the water flowing through the permeable layer and the flow tunnel in the permeable layer changes, the inner pipes are connected to each other. By individually adjusting the amount of water jetted out by the control means, the amount of water injected from each inner pipe into the permeable layer can be made constant.
For this reason, since the amount of heat extracted for each permeable layer in the production well can be equalized, the power generation efficiency can be improved. In addition, since the water injection amount can be changed for each permeable layer without removing the water injection means from the injection well, the workability of power generation can be improved without requiring a complicated operation for changing the water injection amount. In addition, since the water jetted from the communication hole is prevented from leaking along the outer pipe and the anti-wall by the water blocking projection, the pressure loss at the time of water injection into each permeable layer is reduced. Reliable water injection can be performed.

According to the high-temperature rock power generation device of the fifth aspect, the space between the two water-permeable layers is filled between two different water-impervious projections and supplied directly to the power generation means, so that the water-permeable layers are separated from each other. Even if there is a difference in hot water ejection pressure between them, they are not affected by each other. For this reason, the recovery amount of steam or hot water can be increased. Thereby, the efficiency of heat recovery from the high-temperature rock body can be improved, so that the power generation efficiency can be improved.

Further, according to the high-temperature rock power generation device of the sixth aspect, when the temperature of the rock body decreases due to the water flowing through the permeable layer and the flow tunnel in the permeable layer changes, each inner pipe is By individually adjusting the amount of water jetted out by the control means, the amount of water injected from each inner pipe into the permeable layer can be made constant. For this reason, since the amount of heat extracted for each permeable layer in the production well can be equalized, the power generation efficiency can be improved. In addition, since the water injection amount can be changed for each permeable layer without taking out the water injection means from the injection well, complicated work for changing the water injection amount is not required, and the workability of power generation can be improved. In addition, since the water jetted from the communication hole is prevented from leaking through the outer tube and the anti-wall by the water-blocking projection, the pressure loss when water is injected into each permeable layer is reduced. Reliable water injection can be performed.

Further, by filling between two different water-impervious projections for each water-permeable layer and directly supplying it to the power generation means, even if there is a difference in hot water jet pressure between the water-permeable layers. They are not affected by each other. For this reason, the recovery amount of steam or hot water can be increased. This allows
Since the efficiency of heat recovery from the high-temperature rock can be improved, the power generation efficiency can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic side view showing the entire hot rock power generation device of the present invention.

FIG. 2 is a cross-sectional view showing a state cut along a line II-II in FIG. 1;

FIG. 3 is a schematic side view showing an entire excavator for excavating a boring pit.

FIG. 4 is a side view showing a main part of an excavator for excavating a borehole.

FIG. 5 is a side view showing a water injection means of the conventional hot rock power generation device.

[Explanation of symbols]

 Reference Signs List 5 high-temperature rock 7 injection well 9 water pump 19 water-permeable layer 20 water injection means 21 outer pipe 22 partition wall 23 partition space 24 communication hole 25 water-blocking projection 26 inner pipe 30 production well 31 recovery means 32 power generation means 33 control means 34 high-temperature rock Body power generator

Claims (6)

[Claims] 1. A water injection step of feeding water to a plurality of permeable layers in the high-temperature rock body at an injection well formed in the high-temperature rock body, and the water is heated while flowing through the permeable layer to generate steam or hot water. Heating step, and a recovery step of recovering the steam or hot water from the permeable layer in a production well formed in the high-temperature rock body,
A high-temperature rock power generation method, comprising: a power generation step of generating power by using the steam or hot water recovered in the recovery step.In the high-temperature rock power generation method, water is independently supplied to each of the permeable layers in the water injection step, and injection is performed for each of the permeable layers. A hot rock power generation method characterized by controlling the amount of water. 2. A water injection step of feeding water to a plurality of permeable layers in the high-temperature rock body at an injection well formed in the high-temperature rock body, and heating the water while flowing through the permeable layer to produce steam or hot water. Heating step, and a recovery step of recovering the steam or hot water from the permeable layer in a production well formed in the high-temperature rock body,
And a power generation step of generating power using the steam or hot water collected in the recovery step.In the high-temperature rock mass power generation method, the steam or hot water is recovered independently for each of the permeable layers in the recovery step. High-temperature rock power generation method. 3. A water injection step in which water is supplied to a plurality of permeable layers in the high-temperature rock body by an injection well formed in the high-temperature rock body, and the water is heated while flowing through the permeable layer to generate steam or hot water. Heating step, and a recovery step of recovering the steam or hot water from the permeable layer in a production well formed in the high-temperature rock body,
A high-temperature rock power generation method, comprising: a power generation step of generating power by using the steam or hot water recovered in the recovery step.In the high-temperature rock power generation method, water is independently supplied to each of the permeable layers in the water injection step, and injection is performed for each of the permeable layers. A high-temperature rock power generation method, comprising controlling the amount of water and independently collecting the steam or hot water for each of the permeable layers in the collection step. 4. An injection well formed in the high-temperature rock, water injection means for feeding water to a plurality of permeable layers in the high-temperature rock and heating it to produce steam or hot water, and water injection means formed in the high-temperature rock. A high temperature rock power generation device comprising: a recovery unit that recovers the steam or hot water from the permeable layer in a production well; and a power generation unit that generates power using the steam or hot water recovered by the recovery unit. The water injection means communicates with the outer pipe, a plurality of partition walls perpendicular to the longitudinal direction that partition the inside of the outer pipe in the longitudinal direction, and a partition space between the adjacent partition walls and the outside of the outer pipe. A hole, an annular water-impervious projection formed on the outer periphery of a portion of the outer pipe where the partition wall is formed, and a downstream end opening in each of the partition spaces accommodated in the outer pipe and upstream. A plurality of inner pipes whose sides are attached to the water pump, Control means for adjusting the amount of water to be ejected for each of said inner pipes. 5. An injection well formed in the high-temperature rock, water injection means for feeding water to a plurality of permeable layers in the high-temperature rock and heating it to produce steam or hot water. A high temperature rock power generation device comprising: a recovery unit that recovers the steam or hot water from the permeable layer in a production well; and a power generation unit that generates power using the steam or hot water recovered by the recovery unit. The collection means includes an outer tube, a plurality of partition walls perpendicular to the longitudinal direction that partition the inside of the outer tube in the longitudinal direction, and a communication that communicates a partition space between the adjacent partition walls and the outside of the outer tube. A hole, an annular water-impervious projection formed on the outer periphery of a portion of the outer pipe where the partition wall is formed, and an upstream end opening in each of the partition spaces accommodated in the outer pipe and downstream. Side having a plurality of inner pipes connected to the power generation means. High-temperature rock power generation equipment. 6. An injection well formed in the high-temperature rock, water injection means for feeding water into a plurality of permeable layers in the high-temperature rock and heating it to produce steam or hot water, and water injection means formed in the high-temperature rock. A high temperature rock power generation device comprising: a recovery unit that recovers the steam or hot water from the permeable layer in a production well; and a power generation unit that generates power using the steam or hot water recovered by the recovery unit. The water injection means communicates with the outer pipe, a plurality of partition walls perpendicular to the longitudinal direction that partition the inside of the outer pipe in the longitudinal direction, and a partition space between the adjacent partition walls and the outside of the outer pipe. A hole, an annular water-impervious projection formed on an outer periphery of a portion of the outer tube where the partition wall is formed, and a downstream end opening in each of the partition spaces accommodated in the outer tube and upstream. A plurality of inner pipes whose sides are attached to the water pump, A control means for adjusting the amount of water to be ejected for each of the inner pipes is provided, and the recovery means is adjacent to an outer pipe, and a plurality of partition walls perpendicular to the longitudinal direction that partition the inside of the outer pipe in the longitudinal direction. A communication hole that communicates a partition space between the partition walls with the outside of the outer pipe, an annular water-impervious projection formed on an outer periphery of a portion of the outer pipe where the partition wall is formed, and the outer pipe And a plurality of inner pipes each of which has an upstream end opening in each of the partition spaces and a downstream side connected to the power generation means.