JP7265975B2 - oil recovery system - Google Patents

Description

The present invention relates to oil recovery systems.

Conventionally, as a method of recovering oils in the ground, there was a method of blocking the opening of the strainer of the well and pumping up the groundwater and oil that flowed into the pumping well from the opening above the blocked part (for example, , see Patent Document 1). There is also a method of sucking liquid in the ground by connecting a drain material placed in a target range of the ground to a vacuum pump (see, for example, Patent Document 2).

Japanese Patent No. 5316886 JP 2017-185466 A

However, in the method of Patent Document 1, groundwater and oil are allowed to flow into the pumping well due to the difference in water head between the inside of the pumping well and the ground. Therefore, it took time for the oil to move and flow into the pumping well.

Moreover, in the method of Patent Document 2, the position of the drain material in the ground is fixed. Therefore, when the oil layer moves along with the up-and-down movement of the groundwater level, the suction range of the drain material and the position of the oil layer do not match, and the oil recovery efficiency is lowered.

SUMMARY OF THE INVENTION The present invention has been made in view of the problems described above, and an object of the present invention is to provide an oil recovery system capable of maintaining oil recovery efficiency even when the groundwater level fluctuates.

In order to achieve the above-mentioned objects, the present invention provides a well provided in the ground of a site and having a strainer pipe partly having a perforated section with holes, and the presence of an oil layer in the well. an oil recovery drain disposed near the groundwater table, a suction hose having one end connected to the oil recovery drain and the other end extending, and a vacuum suction part connected to the other end of the suction hose and clogging means through which said suction hose is passed and which blocks said well at a position above said perforated section of said strainer tube.

In the present invention, since the oil recovery drain is arranged in the well, the oil that has flowed into the well from the oil reservoir can be directly sucked. In addition, since the well is blocked at a position above the perforated section of the strainer pipe and the vicinity of the drain for oil recovery is sucked by applying a negative pressure, the oil is quickly transferred into the well compared to the case where the difference in water head is used as the driving force. It can be moved and collected.

Said closure means are for example packers, balloons, rubber plugs or membranes.
As a result, the well can be blocked with a simple configuration.

A plurality of said blocking means may be installed in said well.
As a result, the well can be blocked more reliably.

It is desirable that the oil recovery drain is vertically movable within the well. In this case, the suction hose may be vertically movable with respect to the blocking means.
If the oil recovery drain can move up and down in the well, the oil recovery efficiency can be maintained by easily following the position of the oil recovery drain when the ground water table in which the oil layer exists moves up and down. For example, a float may be attached to the oil recovery drain as a method of making the position of the oil recovery drain follow the vertical movement of the groundwater table. Further, if the suction hose can move up and down with respect to the blocking means, the oil recovery drain can be moved while the position of the blocking means is fixed.

The oil recovery drain may be a paper drain or a plastic board drain, and the cross section in the direction perpendicular to the depth direction of the well may have a cross section, a bent section, or a curved section. Further, the oil recovery drain may be a paper drain or a plastic board drain, and the cross section of the well in the depth direction may have a curved portion or a bent portion.
As a result, when there is sufficient oil in the well, the oil can be recovered more efficiently than when using a normal planar oil recovery drain.

Bio-purification may be performed by blowing air from the oil recovery drain into the vicinity of the oil layer through the suction hose.
This also makes it possible to purify oil-contaminated soil when the oil layer becomes emulsified or when the oil layer becomes thin.

It may further comprise an oil recovery drain placed in the ground within the site.
As a result, it is possible to easily increase the number of oil recovery drains.

The well is preferably an existing observation well.
As a result, an oil recovery system can be constructed at low cost without constructing a new well.

ADVANTAGE OF THE INVENTION According to this invention, the oil recovery system which can maintain the recovery efficiency of oil even if a groundwater level fluctuates can be provided.

A plan view of site 9 where an oil recovery system is installed. FIG. 2 is a vertical cross-sectional view of the oil recovery system 2; Sectional drawing of the well 1a. The figure which shows the state which moved the drain 15 for oil collection|recovery in the well 1a. Fig. 3 shows another oil recovery system; Sectional drawing of the direction orthogonal to the depth direction of the well 1a of another drain for oil recovery. Sectional drawing of the depth direction of the well 1a of another drain for oil recovery. A plan view of site 9 where an oil recovery system is installed.

Preferred embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a plan view of a site 9 where an oil recovery system according to the first embodiment is installed, and FIG. 2 is a vertical sectional view of the oil recovery system 2. As shown in FIG. FIG. 2 is a cross-sectional view through line AA of FIG. 3A and 3B are cross-sectional views of the well 1a, FIG. 3A being a cross-sectional view taken along the line BB in FIG. 2, and FIG. 3B being a cross-sectional view taken along the line CC in FIG.

As shown in FIG. 1 , in the oil storage facility 3 , a plurality of observation wells 1 are provided in the ground 5 within the site 9 . The oil recovery system 2 shown in FIG. 2 is installed in a well 1a in which an inflow of oil 11 from an oil storage facility 3 is observed, among existing observation wells 1, for example.

As shown in FIG. 2 , the oil 11 leaking from the oil storage facility 3 into the ground 5 floats on the ground water table 29 to form an oil layer 31 . The oil recovery system 2 is a system for recovering the oil in the oil layer 31 and preventing the oil 11 from flowing out of the site boundary 7 .

As shown in FIG. 2, the oil recovery system 2 comprises an oil recovery drain 15, a suction hose 17, a vacuum suction section 19, a packer 21 and the like. A strainer pipe 13 is arranged in the well 1a. The strainer tube 13 is provided with holes 13a in the perforated section 14 .

The oil recovery drain 15 is composed of a plate-like core material and a filter nonwoven fabric covering the surface of the core material. The oil recovery drain 15 is basically made of the material of the filter non-woven fabric that can be expected to have a relatively water repellent effect due to its high lipophilicity, but it is also possible to use a plastic board drain or paper drain with further improved water repellency. It is possible. As shown in FIG. 3, the oil recovery drain 15 is flat.

As shown in FIG. 2, the oil recovery drain 15 is arranged near the groundwater table 29 where the oil layer 31 exists in the well 1a. A cap 27 is attached to the upper end of the oil recovery drain 15 . A seal member 23 is provided at the boundary between the oil recovery drain 15 and the cap 27 . The sealing material 23 prevents the inflow of air or the like from the gap between the oil recovery drain 15 and the cap 27 . A seal member 25 is provided at the lower end of the oil recovery drain 15 . The sealing material 25 prevents inflow of air or the like from the lower end of the oil recovery drain 15 .

The entire length of the oil recovery drain 15 functions as a suction portion. The length of the suction portion is set according to the thickness of the target oil layer 31 . The oil recovery drain 15 is arranged in the well 1a so that the suction portion is positioned over the entire thickness of the oil layer 31. As shown in FIG.

One end of the suction hose 17 is connected to the tip of the cap 27 of the oil recovery drain 15, and the other end extends to the ground side. The packer 21 is arranged near the upper end of the strainer pipe 13 through which the suction hose 17 is passed. The packer 21 is blocking means for closing the well 1a and is arranged above the perforated section 14 of the strainer tube 13 . The vacuum suction part 19 is provided on the ground 5 and connected to the other end of the suction hose 17 . The vacuum suction unit 19 does not need to be provided for each oil recovery system 2 on a one-to-one basis, and one vacuum suction unit 19 may be provided for a plurality of oil recovery systems 2 .

As shown in FIG. 1, in the oil storage facility 3, the presence or absence of inflow of oil 11 is observed at a plurality of observation wells 1. FIG. Then, the oil recovery drain 15, the suction hose 17 and the packer 21 are integrally installed in the well 1a where the inflow is observed, and the oil recovery system 2 shown in FIG. 2 is prepared.

The diameter of well 1a used as observation well 1 is usually about 50 to 100 mm. The oil recovery drain 15 may have a width slightly smaller than the diameter of the well 1a and a length covering the entire thickness of the oil layer 31. Therefore, even when integrated with the suction hose 17 and the packer 21, it is lightweight. be. Therefore, it may be thrown into the well 1a manually without using a lifting machine. The packer 21 may be small enough to close the well 1a when inflated, and may be inflated by a manual pump.

After the preparation of the oil recovery system 2 is completed, the vacuum suction part 19 is operated. Since the packer 21 is arranged above the perforated section 14 of the strainer pipe 13 in the oil recovery system 2, when the vacuum suction part 19 is operated, the space below the packer 21 in the well 1a becomes negative pressure. . Therefore, compared to the case where the head difference is used as the driving force, the oil can be moved faster from the oil layer 31 in the ground 5 and flow into the well 1a from the hole 13a. The liquid containing oil that has flowed into the well 1a is sucked from the oil recovery drain 15 and recovered.

If the hole 13a of the strainer pipe 13 exists above the packer 21, air moves between the hole 13a above the packer 21 and the hole 13a below the packer 21 when the vacuum suction unit 19 is operated. Therefore, the space below the packer 21 does not have a negative pressure, making it difficult to obtain the above effects.

After the liquid containing oil is sucked from the well 1a, the contents of oil, air and water in the collected liquid are checked. In order to check the content of oil, air, or water, for example, the recovered liquid may be visually observed, or the recovered liquid may be left still on the ground 5 to separate into water and oils and confirmed. Alternatively, the ratio of oil, water, and air in the recovered liquid may be grasped using concentration and specific gravity. If there is a change in the content of oil, air, or water, the vacuum suction unit 19 is stopped as necessary.

For example, when the amount of air and water in the liquid does not change much and the oil content decreases and falls below a predetermined value, it is determined that the oil has been recovered from the oil layer 31 . Then, the oil recovery drain 15 is moved to another observation well 1 where the inflow of the oil 11 is confirmed. If the amount of oil and air in the liquid decreases and the amount of water increases, it is determined that the groundwater level has risen. Then, the oil recovery drain 15 is moved upward within the well 1a. When the amount of air from the oil recovery drain 15 increases and the amount of liquid decreases, it is determined that the groundwater level has fallen. Then, the oil recovery drain 15 is moved downward within the well 1a. Since the oil recovery drain 15, the suction hose 17, and the packer 21 are lightweight as described above, they may be moved by human power rather than by a heavy lifting machine. Also, a float (not shown) may be attached to the oil recovery drain 15 . By attaching a float, the position of the oil recovery drain 15 can be easily followed by the vertical movement of the ground water table 29 .

FIG. 4 is a diagram showing a state in which the oil recovery drain 15 is moved within the well 1a. The groundwater level fluctuates when oil-containing liquids are sucked up, and it also fluctuates with seasonal changes. In the oil recovery system 2, as shown in FIG. 4(a), when the groundwater level 29a descends from the initial groundwater level 29 (FIG. 2), the packer 21 is once contracted, and the oil recovery drain 15 and the suction hose 17 are connected. The packer 21 is lowered integrally. Then, the oil recovery drain 15 is placed near the groundwater level 29a where the oil layer 31a exists, and the packer 21 blocks the perforated section 14 above.

Thus, in the oil recovery system 2 of the first embodiment, since the oil recovery drain 15 is installed in the well 1a, the oil that has flowed into the well 1a from the oil layer 31 can be directly sucked. At this time, by blocking the well 1a at a position above the perforated section 14 of the strainer pipe 13 and sucking, the oil is moved faster than when the difference in water head is used as a driving force, and is made to flow into the well 1a. Therefore, the oil collection efficiency is good. In addition, since the oil recovery drain 15 can move up and down in the well 1a, the position of the oil recovery drain 15 can easily follow the vertical movement of the groundwater table 29 where the oil layer 31 exists. It is possible to maintain the oil recovery efficiency even when moving. Furthermore, by diverting the existing observation well 1 to the well 1a for the oil recovery system 2, the oil recovery system 2 can be constructed at low cost without installing a new well 1a.

In the oil recovery system 2 , the oil recovery drain 15 , the suction hose 17 and the packer 21 are integrated, but the suction hose 17 may be vertically movable with respect to the packer 21 . In the oil recovery system 2a shown in FIG. 4(b), when the groundwater level 29a descends below the initial groundwater level 29 (FIG. 2), the fixation between the packer 21 and the suction hose 17 is temporarily released, and the oil recovery drain 15 is released. and the suction hose 17 are lowered together. Then, the oil recovery drain 15 is arranged near the groundwater level 29a where the oil layer 31a exists, and the packer 21 and the suction hose 17 are fixed again. If the suction hose 17 is vertically movable with respect to the packer 21 in this manner, the oil recovery drain 15 can be vertically moved while the packer 21 is fixed at a position above the perforated section 14 without being moved. Therefore, even if the groundwater level rises from the initial groundwater level 29 (FIG. 2), it can be handled.

Although the packer 21 is used as the blocking means in the oil recovery system 2, the blocking means is not limited to this. Any blocking means may be used as long as it can block the well 1a while the suction hose 17 is passed therethrough. For example, a balloon, a rubber stopper, or a membrane may be used. As described above, since the diameter of the well 1a used as the observation well 1 is small, it can be closed with a simply constructed closing means.

Moreover, the position of the blocking means is not limited to the vicinity of the upper end of the strainer pipe 13 shown in FIG. is not limited to

FIG. 5 is a diagram showing another oil recovery system. In the oil recovery system 2b shown in FIG. 5(a), packers 21 are installed at two locations in the well 1a. In the oil recovery system 2 b , another packer 21 a is installed below the packer 21 near the upper end of the strainer pipe 13 . The packer 21a plugs the well 1a at a position directly above the perforated section 14 of the strainer tube 13. As shown in FIG. In the oil recovery system 2b, for example, when the suction hose 17 is fixed to the packers 21, 21a and the oil recovery drain 15 follows the vertical movement of the groundwater level, the packer 21a is moved when the groundwater level rises. The well 1a can be closed at a position above the perforated section 14 by using the packer 21 when the groundwater level is lowered.

In the oil recovery system 2c shown in FIG. 5(b), a portion of the packer 21b is installed near the uppermost hole 13a of the strainer pipe 13. As shown in FIG. In this case also, the packer 21b closes the well 1a at a position above the perforated section 14 of the strainer pipe 13, so that the space below the packer 21b in the well 1a is made negative pressure by suctioning with the vacuum suction unit 19. It is possible to obtain the same effect as in the first embodiment.

Although the flat oil recovery drain 15 is used in the first embodiment, the shape of the oil recovery drain is not limited to this. Since the oil recovery drain of the first embodiment is installed in the well 1a, it has a higher degree of freedom in shape than when it is placed in the ground 5. FIG. Therefore, an oil recovery drain processed into a shape corresponding to the diameter of the well and the thickness of the oil layer 31 can be selected. If the oil recovery drain is a plastic board drain, molding is easy.

FIG. 6 is a cross-sectional view in a direction orthogonal to the depth direction of the well 1a of another oil recovery drain. The oil recovery drain 15a shown in FIG. 6(a) has a cross section in the direction orthogonal to the depth direction of the well 1a. The oil recovery drain 15a has a radial (cross-shaped) cross section in a direction orthogonal to the depth direction of the well 1a. The oil recovery drain 15b shown in FIG. 6(b) and the oil recovery drain 15c shown in FIG. 6(c) have a curved section in the direction orthogonal to the depth direction of the well 1a. The oil recovery drain 15b shown in FIG. 6(b) has a circular cross section in the direction orthogonal to the depth direction of the well 1a. The oil recovery drain 15c shown in FIG. 6(c) has an arc-shaped cross section in the direction orthogonal to the depth direction of the well 1a. Thus, the cross section of the oil recovery drain 15a in the direction orthogonal to the depth direction of the well 1a can be a crossing portion, a bent portion, a curved portion, or the like.

FIG. 7 is a cross-sectional view in the depth direction of a well 1a of another oil recovery drain. The oil recovery drain 15d shown in FIG. 7(a) has a curved section in the depth direction of the well 1a. The oil recovery drain 15d has a wavy cross section in the depth direction of the well 1a. The oil recovery drain 15e shown in FIG. 7(b) has a curved section in the depth direction of the well 1a. The oil recovery drain 15e has a triangular wave-like cross section in the depth direction of the well 1a.

In the oil recovery drains as shown in FIGS. 6 and 7, the surface area of the suction portion is larger than that of the normal flat plate-like oil recovery drain 15 . Therefore, in a state in which a sufficient amount of oil has flowed into the well 1a, the oil can be recovered more efficiently than in the case of using a normal flat oil recovery drain 15. FIG. In the oil recovery system of the first embodiment, by making the well 1a negative pressure with the vacuum suction part 19, sufficient oil can be collected in the well 1a. , it is considered that the use of the oil recovery drain as shown in FIG.

In the first embodiment, the other end of the suction hose 17 is connected to the vacuum suction section 19, but the other end of the suction hose 17 may be connectable to the compressor. In this case, when it is determined that the oil layer 31 has become thin, such as when the oil layer 31 is emulsified or when the amount of recovered oil is less than a predetermined amount, a compressor (not shown) is operated to Biopurification can be performed by blowing air from the oil recovery drain 15 into the vicinity of the oil layer 31 to activate living microorganisms. Nutrients and microorganisms may be injected into the well 1a as necessary. By performing bioremediation, it becomes possible not only to recover oils but also to purify soil contaminated with oils.

Next, a second embodiment will be described. 2nd Embodiment demonstrates a different point from 1st Embodiment, A description is abbreviate|omitted by attaching|subjecting the same code|symbol in a figure etc. about the same structure. Also, the configurations of the first and second embodiments can be combined as needed.

FIG. 8 is a plan view of a site 9 where an oil recovery system according to a second embodiment of the invention is installed. The second embodiment mainly differs from the first embodiment in that it has an oil recovery drain 33 .

In the second embodiment, an oil recovery drain 33 is installed in the ground 5 within the site 9 . The oil recovery drain 33 is installed, for example, on the site boundary 7 side of the well 1a in which the oil recovery system is installed. The oil recovery drain 33 is connected to the vacuum suction section via a suction hose (not shown). Then, of the oil 11 that has leaked from the oil storage facility 3 into the ground 5, the oil that has flowed into the well 1a is sucked by the oil recovery drain of the oil recovery system, and flows toward the site boundary 7 from the well 1a. The oil recovery drain 33 in the ground 5 sucks and recovers the oil.

In the second embodiment, when the oil 11 leaking from the oil storage facility 3 into the ground 5 cannot be recovered only by the oil recovery system installed in the well 1a, the oil recovery drain 33 can be easily added. .

Although the preferred embodiments of the present invention have been described above with reference to the accompanying drawings, the present invention is not limited to such examples. It is obvious that a person skilled in the art can conceive of various modifications or modifications within the scope of the technical ideas disclosed in the present application, and these naturally belong to the technical scope of the present invention. Understood.

For example, in the present embodiment, the oil recovery drain 15 and the like are installed in the well 1a after confirming the inflow of the oil 11. Then, when the inflow of the oil 11 is confirmed, the packer 21 may close the well and start vacuum suction. Further, the well in which the oil recovery system is installed is not limited to the existing observation well 1, and may be an existing pumping well. Furthermore, an oil recovery system may be installed by newly constructing a well at a location where the oil 11 is expected to spread.

1…………Observation well 1a……Well 2, 2a, 2b, 2c……Oil recovery system 3……Oil storage facility 5……Ground 7……Site boundary 9……Site 11…… ... Oil 13 Strainer pipe 13a Hole 14 Perforated section 15, 15a, 15b, 15c, 15d, 15e, 33 Oil recovery drain 17 Suction hose 19 Vacuum suction part 21, 21a, 21b Packer 23, 25 Seal material 27 Cap 29, 29a Underground water table 31, 31a Oil layer

Claims (10)

A well provided in the ground within the site and having a strainer pipe partly having a perforated section provided with a hole ;
An oil recovery drain disposed near the groundwater table where the oil layer exists in the well;
a suction hose having one end connected to the oil recovery drain and the other end extending;
a vacuum suction part connected to the other end of the suction hose;
closure means through which the suction hose passes and blocks the well at a location above the perforated section of the strainer tube;
An oil recovery system comprising: 2. An oil recovery system according to claim 1, wherein said blocking means is a packer, balloon, rubber plug or membrane. 3. The oil recovery system according to claim 1, wherein said well is provided with a plurality of said blocking means. 4. The oil recovery system according to any one of claims 1 to 3, wherein said oil recovery drain is vertically movable within said well. 5. The oil recovery system according to claim 4, wherein said suction hose is vertically movable with respect to said blocking means. The oil recovery drain is a paper drain or a plastic board drain, and the cross section in the direction orthogonal to the depth direction of the well has a cross section, a bent section, or a curved section. 6. The oil recovery system according to any one of 5. 6. The oil recovery drain according to any one of claims 1 to 5, wherein the oil recovery drain is a paper drain or a plastic board drain, and the cross section of the well in the depth direction has a curved portion or a bent portion. oil recovery system. 8. The oil recovery system according to any one of claims 1 to 7, wherein air is blown into the vicinity of the oil layer from the oil recovery drain through the suction hose to perform bio-purification. 9. The oil recovery system according to any one of claims 1 to 8, further comprising an oil recovery drain placed in the ground within the site. 10. The oil recovery system according to any one of claims 1 to 9, wherein said well is an existing observation well.

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