Cement milk injection method and cement milk injection device

Abstract

To provide a cement milk injection method and a cement milk injection device capable of preventing corrosion of a first casing pipe.SOLUTION: A cement milk injection method includes injecting cement milk from a cement milk supply pipe 2 while a downward open side between the cement milk supply pipe 2 and a first casing pipe 1 is approximately sealed by first sealing means S1, and an upward open side between a second casing pipe 3 and the first casing pipe 1 is approximately sealed by second sealing means S1, thereby filling the cement milk on the outside of the first casing pipe 1.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a cement milk injection method and a cement milk injection device, and more particularly to a cement milk injection method and a cement milk injection device that can prevent corrosion of a first casing pipe. [Background technology]

[0002] Conventionally, when drilling for a hot spring, a borehole is drilled using a drilling machine, and after drilling, an outer pipe is buried in the borehole and an inner pipe is buried in the outer pipe. Cement milk is then supplied from the inner pipe and injected between the borehole and the outer pipe to solidify and protect the outer pipe (see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 3-44623 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the above construction method, the end between the borehole and the outer pipe is open and communicates with the outside air (see, for example, Figure 7 of Patent Document 1), and even if cement milk is injected between the borehole and the outer pipe, the injection pressure of the cement milk does not increase, and the cement mill does not reach the passage (aquifer) for acidic groundwater flowing into the anti-wall, making it easier for acidic groundwater to penetrate into the anti-wall, resulting in the problem of corrosion of the outer pipe.

[0005] SUMMARY OF THE INVENTION An object of the present invention is to provide a cement milk injection method and cement milk injection device that have been made in consideration of the above problems. [Means for solving the problem]

[0006] The cement milk injection method described in claim 1 comprises a first casing pipe placed underground, a cement milk supply pipe placed within this first casing pipe, a second casing pipe located outside the first casing pipe and extending from underground to above ground, a first sealing means for approximately sealing the downward open side of the first casing pipe between the cement milk supply pipe and the first casing pipe, and a second sealing means for approximately sealing the upward open side of the second casing pipe between the second casing pipe and the first casing pipe, and in this state the downward open side between the cement milk supply pipe and the first casing pipe is approximately sealed by the first sealing means, and the upward open side between the second casing pipe and the first casing pipe is approximately sealed by the second sealing means, and the cement milk is injected from the cement milk supply pipe to fill the outside of the first casing pipe with the cement milk.

[0007] In addition, the cement milk injection method described in claim 2 is the cement milk injection method described in claim 1, which is provided with a discharge pipe connected to the above-ground portion of the second casing pipe and discharges the cement milk between the first casing pipe and the second casing pipe to the outside air, and an operating unit that opens and closes the passage within the discharge pipe, and when the concentration of the cement milk discharged from the discharge pipe reaches a predetermined value, the operating unit is operated to close the passage within the discharge pipe.

[0008] Furthermore, the cement milk injection method described in claim 3 is the cement milk injection method described in claim 1, wherein the second sealing means either fastens a second outer flange extending outward from the upper open end of the second casing pipe to a first outer flange extending outward from the upper open end of the first casing pipe, or interposes a sealing member between the first casing pipe and the second casing pipe.

[0009] In addition, the cement milk injection method described in claim 4 is the cement milk injection method described in claim 1, in which the first sealing means is a donut-shaped air-containing member (air packer) between the inner wall of the first casing pipe and the outer wall of the cement milk supply pipe opposite this inner wall.

[0010] The cement milk injection device described in claim 5 comprises a first casing pipe placed underground, a cement milk supply pipe placed within the first casing pipe, a second casing pipe located outside the first casing pipe and extending from underground to above ground, a first sealing means for substantially sealing the downward open side of the first casing pipe between the cement milk supply pipe and the first casing pipe, and a second sealing means for substantially sealing the upward open side of the second casing pipe between the second casing pipe and the first casing pipe, and the cement milk is injected from the cement milk supply pipe to fill the outside of the first casing pipe with the cement milk while the downward open side between the cement milk supply pipe and the first casing pipe is substantially sealed by the first sealing means and the upward open side between the second casing pipe and the first casing pipe is substantially sealed by the second sealing means.

[0011] In addition, the cement milk injection device described in claim 6 is the cement milk injection device described in claim 5, which is provided with a discharge pipe connected to the above-ground portion of the second casing pipe and discharges the cement milk between the first casing pipe and the second casing pipe to the outside air, and an operating unit that opens and closes the passage within the discharge pipe, and when the concentration of the cement milk discharged from the discharge pipe reaches a predetermined value, the operating unit is operated to close the passage within the discharge pipe.

[0012] Furthermore, the cement milk injection device described in claim 7 is the cement milk injection device described in claim 5, wherein the second sealing means either fastens a first outer flange extending outward from the upper open end of the second casing pipe to a first outer flange extending outward from the upper open end of the first casing pipe, or interposes a sealing member between the first casing pipe and the second casing pipe.

[0013] In addition, the cement milk injection device described in claim 8 is the cement milk injection device described in claim 5, in which the first sealing means is a donut-shaped air-containing member (air packer) between the inner wall of the first casing pipe and the outer wall of the cement milk supply pipe opposite this inner wall.

[0014] Furthermore, the cement milk injection method described in claim 9 is the cement milk injection method described in claim 2, in which after injecting the cement milk, the cement milk is injected into the second casing pipe from the above-ground portion of the second casing pipe.

[0015] In addition, the cement milk injection method described in claim 10 is the cement milk injection method described in claim 2, in which after injecting the cement milk, the cement milk is injected into the second casing pipe from the above-ground part of the second casing pipe by connecting the cement milk injection passage of the discharge pipe. [Effects of the Invention]

[0016] According to the cement milk injection method of claim 1, the first sealing means substantially seals the downward open side between the cement milk supply pipe and the first casing pipe, and the second sealing means substantially seals the upward open side between the second casing pipe and the first casing pipe, Cement milk is injected from the cement milk supply pipe to fill the outside of the first casing pipe with cement milk, so that the cement milk can be filled under high pressure not only in the area outside the first casing pipe but also in the underground waterway flowing into the area outside the first casing pipe, thereby preventing corrosion of the first casing pipe due to strong acidic water flowing in through the underground waterway and extending the life of the first casing pipe.

[0017] According to the cement milk injection method of claim 2, the method of claim 1 can be carried out. In addition to the effect of clarity, when the concentration of the cement milk discharged from the discharge pipe reaches a predetermined value, the operating part is operated to close the passage inside the discharge pipe, so that the concentration of the cement milk can be confirmed from the outside, and the outside of the first casing pipe is solidified with cement of a predetermined concentration, thereby protecting the first casing pipe.

[0018] Furthermore, according to the cement milk injection method of claim 3, in addition to the effect of the invention of claim 1, the second sealing means fastens the first outer flange projecting outward from the upper open end of the second casing pipe to the first outer flange projecting outward from the upper open end of the first casing pipe, or Alternatively, a sealing member is interposed between the first casing pipe and the second casing pipe, so that the cement milk can be confined and pressurized by simple means and filled not only in the area outside the first casing pipe but also in underground water channels (e.g., cracks formed underground) that flow into the area outside the first casing pipe, thereby preventing corrosion of the first casing pipe due to strongly acidic water, etc., flowing in through the underground water channels and extending the life of the first casing pipe.

[0019] Furthermore, according to the cement milk injection method described in claim 4, in addition to the effects of the invention described in claim 1 above, the first sealing means is a donut-shaped air-containing member (air packer) that abuts against the inner wall of the first casing pipe and the outer wall of the cement milk supply pipe facing this inner wall, so that airtightness can be increased by simple means and backflow of cement milk to the ground can be prevented, and after use, for example, air can be released from the air supply passage (not shown) that supplies air from the ground to the air-containing member (air packer), and recovered when the cement milk supply pipe is pulled up, making post-processing easy.

[0020] According to the cement milk injection device of claim 5, the first sealing means substantially seals the downward open side between the cement milk supply pipe and the first casing pipe, and the second sealing means substantially seals the upward open side between the second casing pipe and the first casing pipe, Cement milk is injected from the cement milk supply pipe to fill the outside of the first casing pipe with cement milk, so that the cement milk can be filled under high pressure not only in the area outside the first casing pipe but also in the underground waterway flowing into the area outside the first casing pipe, thereby preventing corrosion of the first casing pipe due to strong acidic water flowing in through the underground waterway and extending the life of the first casing pipe.

[0021] Furthermore, according to the cement milk injection device described in claim 6, in addition to the effects of the invention described in claim 5 above, when the concentration of the cement milk discharged from the discharge pipe reaches a predetermined value, the operating unit is operated to close the passage inside the discharge pipe, so that the concentration of the cement milk can be confirmed from the outside, and the outside of the first casing pipe can be solidified with cement of a predetermined concentration, thereby protecting the first casing pipe.

[0022] Furthermore, according to the cement milk injection device of claim 7, in addition to the effect of the invention of claim 5, the second sealing means fastens the first outer flange projecting outward from the upper open end of the second casing pipe to the first outer flange projecting outward from the upper open end of the first casing pipe, or Alternatively, a sealing member is interposed between the first casing pipe and the second casing pipe, so that the cement milk can be confined and pressurized by simple means and filled not only in the area outside the first casing pipe but also in underground water channels (e.g., cracks formed underground) that flow into the area outside the first casing pipe, thereby preventing corrosion of the first casing pipe due to strongly acidic water, etc., flowing in through the underground water channels and extending the life of the first casing pipe.

[0023] Furthermore, according to the cement milk injection device described in claim 8, in addition to the effects of the invention described in claim 5 above, the first sealing means is a donut-shaped air-containing member (air packer) that abuts against the inner wall of the first casing pipe and the outer wall of the cement milk supply pipe facing this inner wall, so that airtightness can be increased by simple means and backflow of cement milk to the ground can be prevented, and after use, for example, air can be released from the air supply passage (not shown) that supplies air from the ground to the air-containing member (air packer), and recovered when the cement milk supply pipe is pulled up, making post-processing easy.

[0024] Furthermore, according to the cement milk injection method of claim 9, in addition to the effect of the invention of claim 2 described above, since after the cement milk is injected, the cement milk is injected under pressure into the second casing pipe from the above-ground part of the second casing pipe, and therefore the cement milk filling the space between the first casing pipe and the second casing pipe settles after the cement milk is injected, creating a void at the top, and therefore it is possible to inject the cement milk under pressure from a pipe (not shown) connected to the second casing pipe, thereby preventing corrosion of the first casing pipe due to strong acidic water flowing in through the underground waterway. If the degree of pressurization of the cement milk is increased, the cement milk can be filled deep into the underground waterway. Preferably, the concentration of the cement milk injected under pressure from the cement milk injection passage (not shown) connected to the second casing pipe is higher than the concentration of the cement milk injected from the cement milk supply pipe.

[0025] Furthermore, according to the cement milk injection method described in claim 10, in addition to the effects of the invention described in claim 2 above, after the cement milk is injected, the cement milk is pressurized and injected into the second casing pipe from the above-ground part of the second casing pipe, so that after the cement milk is injected, the cement milk that has filled the space between the first casing pipe and the second casing pipe settles, filling the void that has formed at the top and preventing corrosion of the first casing pipe due to strong acidic water flowing in through an underground waterway, and after the cement milk is injected, the cement milk is injected into the second casing pipe from the above-ground part of the second casing pipe by connecting a cement milk injection passage (not shown) that is connected to the discharge pipe, so that the discharge pipe can be used effectively. Preferably, the concentration of the cement milk injected under pressure from the cement milk injection passage (not shown) connected to the discharge pipe is higher than the concentration of the cement milk injected from the cement milk supply pipe. [Brief explanation of the drawings]

[0026] [Figure 1]FIG. 1 is a schematic diagram of a cement milk injection device according to one embodiment of the present invention. [Figure 2] FIG. 2 is a schematic diagram of another embodiment of the cement milk injection device different from that of FIG. [Figure 3] FIG. 3 is a schematic diagram of another embodiment of the cement milk injection device different from that of FIG. DETAILED DESCRIPTION OF THE INVENTION

[0027] A cement milk injection method and cement milk injection device according to one embodiment of the present invention will be described with reference to FIGS. 1 to 3. FIG.

[0028] M shown in Figure 1 is a cement milk injection device used when drilling hot springs, geothermal energy, wells, etc., and is equipped with a first casing pipe 1 placed underground, a cement milk supply pipe 2 placed within this first casing pipe 1, a second casing pipe 3 located outside the first casing pipe 1 and extending from underground to above ground, a first sealing means S1 that approximately seals the downward open side of the first casing pipe 1 between the cement milk supply pipe 2 and the first casing pipe 1, and a second sealing means S2 that approximately seals the upward open side of the second casing pipe 3 between the second casing pipe 3 and the first casing pipe 1.

[0029] The first casing pipe 1 is excavated by rotary excavation (not shown), and when excavation of a certain section is completed, the first casing pipe 1 (for example, a steel pipe) is placed in that section. The first casing pipe 1 and the cement milk supply pipe 2 are installed apart (floating) from the bottom of the borehole 10. Reference numeral 20 shown in FIG. 1 denotes a concrete foundation.

[0030] With the downward open side between the cement milk supply pipe 2 and the first casing pipe 1 substantially sealed by the first sealing means S1, and with the upward open side between the second casing pipe 3 and the first casing pipe 1 substantially sealed by the second sealing means S2, cement milk is injected from the cement milk supply pipe 2 to fill the outside of the first casing pipe 1 with the cement milk (cement milk injection method). The cement milk is pressurized to 1013 hPa or more, and the higher the pressure, the deeper the cement milk can be filled into the underground waterway communicating with the borehole 10.

[0031] Therefore, according to the above-mentioned cement milk injection device M (cement milk injection method), in particular, the second sealing means S2 allows the cement milk to be filled not only in the area outside the first casing pipe 1 while the cement milk outlet is blocked (high pressure state), but also in the underground waterways 4 and 5 flowing into the area outside the first casing pipe 1, thereby preventing corrosion of the first casing pipe 1 due to strongly acidic water, etc. flowing in through the underground waterways 4 and 5, and extending the life of the first casing pipe.

[0032] Also, reference numeral 6 shown in Figure 1 is a discharge pipe that is connected to the above-ground portion of the second casing pipe 3 and discharges the fluid (mainly cement milk) between the first casing pipe 1 and the second casing pipe 3 to the outside air, and reference numeral 7 is an operating part that opens and closes the passage inside the discharge pipe 6.

[0033] Therefore, when cement milk is injected from the cement milk supply pipe 2 with the first sealing means S1 substantially sealing the downward open side between the cement milk supply pipe 2 and the first casing pipe 1 and the second sealing means S2 substantially sealing the upward open side between the second casing pipe 3 and the first casing pipe 1, the concentration of the cement milk discharged from the discharge pipe 6 gradually increases, and when the concentration reaches a predetermined value, the operating unit 7 is operated to close the passage inside the discharge pipe 6, so that the concentration of the cement milk can be confirmed from the outside, and the outside of the first casing pipe 1 is solidified with cement of a predetermined concentration, thereby protecting the first casing pipe 1. In addition, if solid materials such as crushed hemp rope, bentonite, slime, etc. are mixed into the cement milk injected from the cement milk supply pipe 2, it is effective in sealing the underground waterways 4 and 5 flowing into the area outside the first casing pipe 1.

[0034] The first sealing means S1 mentioned above is located between the inner wall of the first casing pipe 1 and the outer wall of the cement milk supply pipe 2 facing this inner wall, and specifically may be a concrete packing. In the case of the concrete packing shown in Figure 1, the first casing pipe 1 with the concrete packing that abuts against the outer wall of the cement milk supply pipe 2 is prepared in advance, and the first casing pipe 1 with the concrete packing that abuts against the outer wall of the cement milk supply pipe 2 is guided into the excavated shaft and placed as shown in Figure 1. 8 in Figure 1 is a hemp rope. After placement, cement milk is injected from the tip of the cement milk supply pipe 2 to fill a predetermined amount of the cement milk on the outside of the first casing pipe 1, and then it is destroyed by an excavator not shown in the next excavation process.

[0035] The first sealing means S1 is preferably a doughnut-shaped air-containing member (air packer) that abuts against the inner wall of the first casing pipe 1 and the outer wall of the cement milk supply pipe 2 facing this inner wall, as shown in Figure 2. After use, for example, air is vented from an air supply passage (not shown) that supplies air from the ground to the air-containing member (air packer), and the air packer can be recovered when the cement milk supply pipe 2 is lifted up, making post-processing easy. Furthermore, when a concrete packing is used, as shown in Figure 3, a hemp rope 8 or the like is wrapped around the lower part of the reducing socket of the cement milk supply pipe 2, and the hemp rope 8 and the concrete packing are brought into contact with each other to increase airtightness and prevent backflow of cement milk. Therefore, a simple means can be used to increase airtightness and prevent backflow of cement milk to the ground. Furthermore, after use, for example, air is vented from an air supply passage (not shown) that supplies air from the ground to the air-containing member (air packer), and the air packer can be recovered when the cement milk supply pipe 2 is lifted up, making post-processing easy. In more detail, an air-containing member (air packer) is wrapped around the end of the cement milk supply pipe 2, and as the cement milk supply pipe 2 is extended, air-containing members (air packers) are fixed at regular intervals. The pipe is lowered to the desired position and fixed in place. Air is then pumped in from the ground to inflate it into a doughnut shape to prevent backflow of cement milk. After the injection work is completed, the air is released on the ground, and the cement milk supply pipe 2 is removed and the air-containing member (air packer) is retrieved. If a concrete packing is used instead of an air-containing member (air packer) as shown in Figure 3, a hemp rope 8 or similar material is wrapped around the bottom of the reducing socket to increase airtightness and prevent backflow of cement milk. If the concrete packing method is selected, guide rings are fixed at the required intervals to ensure the cement milk supply pipe 2 is inserted securely into the hole in the concrete packing, preventing the cement milk supply pipe 2 from wobbling. In addition, in FIG. 2, 21 is a guide ring that guides the cement milk supply pipe 2 to the center of the cement milk supply pipe 1, and 22 is a reducing socket.

[0036] The second sealing means S2 is formed by fastening the second outer flange 31 projecting outward from the upper open end of the second casing pipe 3 to the first outer flange 11 projecting outward from the upper open end of the first casing pipe 1 (fastening is performed by using a bolt 9, a nut (not shown) screwed onto the bolt 9, welding, etc.), or Alternatively, a sealing member (not shown) may be interposed between the first casing pipe 1 and the second casing pipe 3.

[0037] The above-mentioned second sealing means S2 allows cement milk to be filled under high pressure not only in the area outside the first casing pipe 1 but also in the underground waterways 4 and 5 flowing into the area outside the first casing pipe 1, thereby preventing corrosion of the first casing pipe 1 due to strong acidic water flowing in through the underground waterways 4 and 5, and extending the life of the first casing pipe 1.

[0038] After the cement milk is injected, the cement milk filling the space between the first casing pipe 1 and the second casing pipe 3 settles, creating a void at the top. Strongly acidic water, etc., flowing into this void via underground waterways 4 and 5 corrodes the first casing pipe 1. To prevent this, after the cement milk is injected, the cement milk is pressurized and injected into the second casing pipe 3 from the above-ground part of the second casing pipe 3. The injection is carried out by connecting a cement milk injection passage (not shown) to the discharge pipe 6. That is, by connecting a cement milk injection passage (not shown) to the discharge pipe 6, the discharge pipe 6 can be used effectively. Preferably, the concentration of the cement milk injected under pressure from the cement milk injection passage (not shown) connected to the discharge pipe 6 is higher than the concentration of the cement milk injected from the cement milk supply pipe. This is because if the cement milk is pressurized to a higher degree, the cement milk can be filled deep into the underground waterway.

[0039] The means of injection is not limited to the above-mentioned embodiment, and instead of using the discharge pipe 6, a dedicated cement milk injection passage (not shown) may be connected to the above-ground portion of the second casing pipe 3, and this dedicated cement milk injection passage (not shown) may be connected. Also, as mentioned above, it is desirable that the concentration of the cement milk injected under pressure from the cement milk injection passage (not shown) connected to the second casing pipe 3 should be higher than the concentration of the cement milk injected from the cement milk supply pipe 2. This is because if the degree of pressurization of the cement milk increases, the cement milk can be filled deep into the underground waterway. [Explanation of symbols]

[0040] M Cement milk injection device S1 First sealing means S2 Second sealing means 1. First casing pipe 11 First outer flange 2. Cement milk supply pipe 3 Second casing pipe 31 Second outer flange 4 Underground waterway 5 Underground waterway 6. Exhaust pipe 7 Control section 8 Hemp Rope 9 volts 10 Boreholes 20 Concrete Foundation

Claims

1. a first casing pipe disposed underground; a cement milk supply pipe disposed within the first casing pipe; a second casing pipe located outside the first casing pipe and extending from underground to above ground; a first sealing means for substantially sealing the lower open side of the first casing pipe between the cement milk supply pipe and the first casing pipe; a second sealing means for substantially sealing an upper open side of the second casing pipe between the second casing pipe and the first casing pipe; a first sealing means for sealing the lower open side between the cement milk supply pipe and the first casing pipe, and a second sealing means for sealing the upper open side between the second casing pipe and the first casing pipe, The cement milk is injected from the cement milk supply pipe to fill the outside of the first casing pipe with the cement milk. A cement milk injection method characterized by the above.

2. a discharge pipe connected to a portion of the second casing pipe located above ground, for discharging cement milk between the first casing pipe and the second casing pipe to the outside air; an operating unit for opening and closing a passage in the discharge pipe, When the concentration of the cement milk discharged from the discharge pipe reaches a predetermined value, the operating part is operated to close the passage in the discharge pipe.

2. The method for injecting cement milk according to claim 1.

3. The second sealing means fastens a second outer flange projecting outward from the upper open end of the second casing pipe to a first outer flange projecting outward from the upper open end of the first casing pipe, or Alternatively, a sealing member is interposed between the first casing pipe and the second casing pipe.

2. The method for injecting cement milk according to claim 1.

4. The first sealing means is a doughnut-shaped air-containing member (air packer) that abuts against the inner wall of the first casing pipe and the outer wall of the cement milk supply pipe facing the inner wall.

2. The method for injecting cement milk according to claim 1.

5. a first casing pipe disposed underground; a cement milk supply pipe disposed within the first casing pipe; a second casing pipe located outside the first casing pipe and extending from underground to above ground; a first sealing means for substantially sealing a downward open side of the first casing pipe between the cement milk supply pipe and the first casing pipe; a second sealing means for substantially sealing an upper open side of the second casing pipe between the casing pipe and the first casing pipe, a first sealing means for sealing the lower open side between the cement milk supply pipe and the first casing pipe, and a second sealing means for sealing the upper open side between the second casing pipe and the first casing pipe, The cement milk is injected from the cement milk supply pipe to fill the outside of the first casing pipe with the cement milk. A cement milk injection device characterized by:

6. a discharge pipe connected to a portion of the second casing pipe located above ground, for discharging cement milk between the first casing pipe and the second casing pipe to the outside air; an operating unit for opening and closing a passage in the discharge pipe, When the concentration of the cement milk discharged from the discharge pipe reaches a predetermined value, the operating part is operated to close the passage in the discharge pipe.

6. The cement milk injection device according to claim 5.

7. The second sealing means fastens a second outer flange projecting outward from the upper open end of the second casing pipe to a first outer flange projecting outward from the upper open end of the first casing pipe, or Alternatively, a sealing member is interposed between the first casing pipe and the second casing pipe.

6. The cement milk injection device according to claim 5.

8. The second sealing means is a doughnut-shaped air-containing member (air packer) that abuts against the inner wall of the first casing pipe and the outer wall of the cement milk supply pipe facing the inner wall.

6. The cement milk injection device according to claim 5.

9. After the cement milk is injected, the cement milk is injected into the second casing pipe from the above-ground portion of the second casing pipe.

3. The method for injecting cement milk according to claim 2.

10. After the cement milk is injected, the cement milk is injected into the second casing pipe from the above-ground portion of the second casing pipe by connecting the cement milk injection passage of the discharge pipe.

3. The method for injecting cement milk according to claim 2.

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