JP2000355960A - Intake method for deep ocean water - Google Patents

Abstract

PROBLEM TO BE SOLVED: To carry out, on land, installation works of intake pipes and drainage pipes for deep ocean water, and obtain a large quantity of water and prevent the draining from exerting an adverse influence on an ecological system. SOLUTION: A tunnel 6 having a specified sectional area is constructed from the ground surface 1 to the bottom S of the sea of at least 30 m or deeper level below sea level. Thereafter, water intake pipes 11 and drainage pipes 12 are slid into the tunnel 6 while connecting them from the ground surface 1 and further, an intake device 4 downward slid along the bottom of the sea to immerse the intake pipes 11 is fitted to the tip 11a of the intake pipe 11. After the intake device 4 has been installed on a specified ocean floor, deep ocean water 3 is pumped up through the intake pipes 11 and the deep ocean water 3 after use is discharged into the sea through the drainage pipes 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for withdrawing deep ocean water, and more particularly to a method for installing intake pipes and the like, which can be performed safely on land, and in which large-scale deep ocean water is withdrawn. The present invention also relates to a method for withdrawing deep seawater so that drainage does not adversely affect ecosystems in surrounding sea areas.

[0002]

2. Description of the Related Art Conventionally, a method of withdrawing deep water is to dispose a water intake pipe in which an iron wire is wound around a hard polyethylene pipe from a work boat along a seabed to a deep water intake position and construct a well above the ground. The deep water is taken in by pumping up from the well by attaching the intake pipe to the bottom of the well. In addition, surplus deep water after use is discharged as it is into the surrounding sea area.

[0003]

DISCLOSURE OF THE INVENTION Since deep sea water is seawater aged at a depth of about 200 m (under 20 atm) and aged for many years, eutrophication, cleanliness, low-temperature stability, ripening, mineral properties, etc. It is a valuable marine resource with great potential.

In the conventional deep sea water intake method, it is necessary to protect the vicinity of the surface layer from waves caused by typhoons and the anchors of ships because of the intake of water by pipes, so that the surface is buried in a trench formed on the sea floor or concrete sinker. And the pavement protects the pipe. The inner diameter of the pipe is usually 125 mm or more.
450mm is adopted and the water intake is 1000-3
0000 m ³ / day was common and only a small volume of water could be taken.

[0005] Furthermore, the use of deep ocean water is also limited to small-scale use limited to marine products and foods (liquor, miso, soy sauce, salt) and the like. In addition, the surplus deep water after use has a lower water temperature and a higher salinity than the seawater near the surface layer. Therefore, if the surplus deep water is discharged to the surface layer as it is, it has a great adverse effect on the ecosystem in the surrounding sea area.

Therefore, the installation of the water intake pipe and the like is not affected by waves and the like, so that the work can be safely performed from the land, the capacity of the deep water intake can be increased, and its use range can be expanded. The technical problem to be solved arises in order to obtain a method for withdrawing deep ocean water, which does not affect the ecosystem in the surrounding sea area even after the surplus deep water, and the present invention aims to solve this problem. And

[0007]

DISCLOSURE OF THE INVENTION The present invention has been proposed to achieve the above object. In a method for taking deep ocean water from the ground surface, the present invention is directed toward a seabed at least at a depth of 30 m or more. After constructing a tunnel with a predetermined cross section from the ground surface, an intake pipe and a drain pipe are slid into the tunnel while being joined to each other from the ground surface, and further, the tip of the intake pipe is lowered along the seabed. Attach a water intake device to slide down the water intake pipe, install the water intake device on a predetermined sea floor, and withdraw the deep sea water from the water intake pipe,
It is an object of the present invention to provide a method for withdrawing deep seawater after use, into which the deep seawater is discharged into the sea by the drainage pipe.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below in detail with reference to FIGS. FIG. 1 is a vertical sectional side view showing the state of intake and drainage of deep ocean water. A water intake pipe 11 for taking in deep seawater 3 having a depth (200 to 300 m) from the sea surface 2 is provided along the seabed S. The intake pipe 11 is installed at a position where there is no influence of waves due to a typhoon or the like and protection from an anchor of the ship is not required. Further, in consideration of the position of drainage of the deep sea water after use, which will be described later, the outlet 5b of the intake pipe 11 and the drain pipe 12 to the seabed S is at least 30 m from the sea surface 2.

In order to dispose the intake pipe 11 and the drain pipe 12, boring is performed diagonally from the land portion 5a of the ground surface 1 to the outlet 5b to the sea floor S to construct the tunnel 6. The boring is performed by a boring machine 8 on the land 5a.
Is installed, a hammer bit (not shown) is provided at the tip to drill a rock R, and a drill rod (not shown) that supplies rotation and thrust to the hammer bit and supplies fluid to the cutting edge behind the drill. The boring hole which becomes the tunnel 6 is formed by successively adding the holes. The boring hole 6 is constructed in a circular cross section having an inner diameter of 600 to 800 mm as shown in FIG.
In order to prevent collapse of the hole wall and erosion by seawater, the inside of the inner diameter is formed while sequentially inserting the casing pipe 7.

The casing pipe 7 may be disposed only at the mouth of the land portion 5a or may not be disposed at all depending on the state of the bedrock R. The casing pipe 7 is made of a non-rusting stainless steel or reinforced plastic (FRP) material, and the intake pipes 11 and 11 and the drain pipes 12 and
It also serves as a guide tube for the 12 arrangements. Further, instead of the construction of the boring hole 6, a tunnel which becomes an inclined shaft from the land portion 5a to the outlet 5b to the seabed S may be constructed by a full-section excavator (not shown) or the like. In that case, unloading can be performed while continuously excavating the entire cross section by unmanned mine and monitoring operation on the ground,
A cross section capable of securing a predetermined water intake capacity can be easily formed.

After the boring hole 6 is penetrated, the boring machine 8 is removed, and a plurality of water intake pipes 11, 11 are inserted into the boring hole 6 from the land portion 5a as shown in FIG.
The drain pipes 12, 12 (in this case, two lines) are arranged so as to be in a lotus root-like perforated state. The intake pipe 11 and the drain pipe 12 are formed of a high-density polyethylene (HDPE) pipe, and have a unit length of 5 to 10 m and an outer diameter of 300 to 350.
mm is allowed, and both ends of the pipe are flanged as shown in FIG.
3 is formed. In the case of the intake pipe 11 and the drain pipe 12 alone, the flanges 13 and 1 are provided at the land portion 5a.
The flanges 13 and 13 are pressurized at the same time by applying a current to a part of the butted surface, and the butt seam welding is performed to join the flanges 13 and 13 continuously. The drain pipe 12 is disposed in the boring hole 6 so as to be pushed out toward the outlet 5b.

Next, when the water intake pipe 11 reaches the outlet 5b of the seabed S, the water intake pipe 11 is further disposed along the seabed S at a position where the deep seawater 3 is withdrawn. The water intake device 4 is installed at the tip of the water intake pipe 11. The water intake device 4
When the intake port 11a of the intake pipe 11 is slid down along the seabed S as shown in FIG.
A square pyramid having a predetermined distance from the seabed S in order to protect the seabed S from rocks and the like, and having the intake pipe 11 as a center so as to serve as an anchor for submerging the intake pipe 11. Is a steel structure having the following shape. The distal end of the water intake device 4 is reinforced with diagonal members 15, 15, 15, 15; the central portion is provided with a boss 17 through which the water intake pipe 11 passes; A horizontal member 16, 16, 16, 16 is provided in the longitudinal direction, and a boss portion through which the central portion of the horizontal member 16, 16, 16, 16 passes through the intake tube 11 is provided at the intersection of the horizontal members 16, 16, 16, 16 on the intake tube 11. 18 are provided.

As shown in FIG. 1, the water intake pipe 11 is attached to the distal end of the water intake pipe 11 by connecting the water intake pipe 11 to the outlet 5.
b, the water intake device 4 is suspended by the crane 9 of the work boat and transported to a predetermined position, and then the diver 10 inserts the water intake pipe 11 into each of the bosses 17 and 18 of the water intake device 4. Then, the water intake pipe 11 and the water intake device 4 are fixed with a wire (not shown) or the like. Thereafter, the water intake pipe 11 is joined and sent out at the land portion 5a, and the water intake device 4 is connected.
Is naturally settled along the seabed S to a predetermined intake device for the deep sea water 3 while braking so as not to settle rapidly, and the intake device 4 is settled.

The water intake device 4 is provided in advance with the land portion 5a.
A structure with an umbrella closed is attached to and placed at the tip of the intake pipe 11, and when the intake pipe 11 passes through the outlet 5b, it is automatically opened into an umbrella shape by using spring force or the like. In such a case, the ship may sink along the seabed S.

The deep ocean water 3 from the intake port 11a of the intake pipe 11 is pumped up by a pump (not shown) provided on the land portion 5a, and is carried to a predetermined place by a pipe (not shown). use. The used deep sea water 3 is discharged into the sea near the outlet 5b by the drainage pipe 12 disposed in the borehole 6, as shown in FIG. Although the deep ocean water 3 has a low water temperature and is discharged into the vicinity of the surface layer, it has an adverse effect on benthic organisms and the like. Is less. Further, a pump (not shown) for pumping and discharging the used deep sea water 3 is provided in the land portion 5a of the drain pipe 12.
Is installed and diffused and discharged near the outlet 5b, so that the influence on the surrounding sea area is further reduced.

A check valve (not shown) may be attached to the tip of the drain pipe 12 provided near the outlet 5b to prevent backflow of seawater.

The shapes and sizes of the boreholes, intake pipes and drainage pipes and the materials of the intake pipes and drainage pipes described in the above-mentioned embodiment of the present invention are not limited to those described above. It will be changed appropriately according to the water intake plan.

Thus, the present invention can be variously modified without departing from the spirit of the present invention, and it goes without saying that the present invention extends to the modified ones.

[0019]

As described above, according to the present invention, since a tunnel is constructed from the ground surface toward the seabed at least at a depth of 30 m or more, all the construction work can be performed safely on land. Further, the joining operation of the intake pipe and the drain pipe installed in the tunnel can be easily performed on land. In addition, by arranging a plurality of the intake pipes in the tunnel, it is possible to withdraw a large volume of deep ocean water, which is a conventional small-capacity intake and limited to a small scale such as for food. By utilizing the low-temperature stability of deep water, large-scale utilization of cooling water or a thermal energy system of a thermal power plant becomes possible.

Further, the intake pipe and the drainage pipe can be easily slid toward the seabed by using the tunnel as a guide, and the intake pipe is installed on the seabed having a water depth of 30 m or more. Therefore, there is no need to protect against waves due to typhoons or anchors of ships. In addition, since a water intake device is attached to the tip of the water intake pipe, the water intake apparatus serves as a protection when the water intake pipe is slid to the seabed and as an anchor when sinking.

Since the deep sea water after use is discharged into the sea through the drainage pipe in the tunnel, it has little effect on ecosystems such as benthic organisms.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional side view showing an embodiment of the present invention and showing a state of intake and drainage of deep water.

FIG. 2 is a sectional view taken along line XX of FIG.

FIG. 3 is a longitudinal sectional view showing a joined state of an intake pipe (drain pipe).

FIG. 4 is a perspective view showing a water intake device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ground surface 3 Deep sea water 4 Intake apparatus 6 Tunnel (boring hole) 11 Intake pipe 11a Tip of intake pipe 12 Drain pipe S Submarine

Claims (1)

[Claims] In a method for taking deep ocean water from the ground surface, a gallery having a predetermined cross section from the ground surface is constructed at least toward a seabed at a depth of 30 m or more, and then an intake pipe and a drain pipe are provided in the gallery. Are connected to the ground surface, and further, a water intake device is attached to the tip of the water intake pipe to slide down the water intake pipe along the seabed to sink the water intake pipe. A method for taking in deep sea water, wherein the method is installed on the seabed, takes in the deep sea water from the intake pipe, and discharges the used deep sea water into the sea by the drain pipe.