Underwater sediment recovery system and underwater sediment recovery method

The sediment recovery system addresses hose-related movement obstacles by discharging sediment into a transport boat's bucket, ensuring stable robot movement and efficient sediment transfer in nuclear power plants.

JP2025004447APending Publication Date: 2025-01-15TOKYO ELECTRIC POWER CO HOLDINGS INC
View PDF 2 Cites 0 Cited by

Patent Information

Application Number
JP2023104139
Authority / Receiving Office
JP · JP
Patent Type
Applications
Current Assignee / Owner
Filing Date
2023-06-26
Publication Date
2025-01-15

AI Technical Summary

Technical Problem

Existing underwater sediment collection systems face issues with hoses obstructing robot movement and increasing load when transferring sediment over long distances, particularly in nuclear power plant environments where sediment is scattered over a wide area.

Method used

A sediment recovery system comprising a robot with a discharge nozzle that discharges sediment into a transport boat's bucket, allowing the robot to move freely without a hose, and a transport boat that collects sediment from the robot's nozzle and transports it to a collection site.

Benefits of technology

The system enables efficient sediment collection by reducing the load on the robot and preventing hose interference, allowing stable movement and efficient sediment transfer without the need for long hoses.

✦ Generated by Eureka AI based on patent content.

Smart Images

  • Figure 2025004447000001_ABST
    Figure 2025004447000001_ABST
Patent Text Reader

Abstract

To provide an underwater sediment recovery system and an underwater sediment recovery method capable of preventing a hose from interfering with the movement of a robot and reducing the load imposed when the robot moves while pulling the hose.SOLUTION: An underwater sediment recovery system of the present invention is configured as an underwater sediment recovery system 100a that recovers and accumulates sediment from a flooded floor and includes a robot 100 that travels across the flooded floor to suck up the sediment, a discharge nozzle 156 positioned on top of the robot to discharge the sucked up sediment to an outside, and a transport boat 200 that can travel on the water surface of the floor. The transport boat 200 has a bucket 210 with an openable and closable bottom, a float 220 that floats the bucket on the water surface, and a screw 230 that moves the bucket. The discharge nozzle 156 is installed in a position where it can discharge sediment into the bucket of the transport boat adjacent to the robot.SELECTED DRAWING: Figure 2
Need to check novelty before this filing date? Find Prior Art

Description

[Technical field]

[0001] The present invention relates to an underwater sediment recovery system that recovers and accumulates sediment from a flooded floor, and an underwater sediment recovery method using the same. [Background technology]

[0002] Conventionally, in order to prevent water pollution and to remove harmful substances that have settled in the water, sediments that have settled in the water have been collected. As a means for collecting sediments, for example, Patent Document 1 discloses a sludge collection device and method. The sludge collection device of Patent Document 1 includes a dredging device that is movable underwater and capable of sucking and collecting sludge from the bottom of the water, a treatment device that is movable underwater and stores the collected material in a collected material receiving tank after removing water from the sludge collected by the dredging device, and an equipment vehicle that supplies electricity, compressed air, and the like to the treatment device.

[0003] Incidentally, for example, in a nuclear power plant building, sandbags containing an adsorbent (e.g., zeolite) that adsorbs radioactive materials are sometimes placed in water to reduce the amount of radiation in the water. When recovering the contents of these sandbags, if the contents remain in the sandbags, the sludge recovery device of Patent Document 1 cannot recover the sediment.

[0004] The inventors then developed an underwater sediment recovery robot that "includes a robot body capable of moving underwater, a container attached to the robot body, a built-in pump mounted on the robot body and which sucks up sediment through the container, and a tipped saw that is pivoted vertically on the front of the lower part of the robot body and can rotate freely" (Patent Document 2).

[0005] According to the underwater sediment recovery robot of Patent Document 2, the robot body rotates left and right while pressing a tipped saw against the sandbags to break them, and the contents that spill out of the sandbags can be sucked up and recovered by the built-in pump of the robot body. Therefore, even if the contents are contained in the sandbags, the contents can be efficiently recovered, and sediment recovery work can be performed quickly. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2014-125754 A [Patent Document 2] JP 2022-147083 A Summary of the Invention [Problem to be solved by the invention]

[0007] The inventors have studied a method for recovering sediment stored in a container of the underwater sediment recovery robot (hereinafter referred to as the robot) of Patent Document 2. In detail, they have studied the following operation method: "The robot with the sediment stored in the container is moved to a collection site, and the container is removed from the robot. The sediment inside the container is then released to the collection site. After that, the robot is connected to a suction device installed at the collection site, and the zeolite inside the container is sucked up by the suction device."

[0008] Furthermore, the inventors considered an operation method in which the sediment collected by the robot is directly transported to a collection location without storing it in a container, so that various collection methods can be applied according to the local conditions. In this case, the discharge outlet of the hose connected to the robot is placed at the collection location to transport the sediment. However, because the sediment is scattered over a wide area of ​​the floor, the length of the hose can be up to 50m or more. In that case, the robot moves while pulling the hose, and there is a possibility that the hose may hinder the movement of the robot.

[0009] In view of these problems, the present invention aims to provide an underwater sediment recovery system and an underwater sediment recovery method in which the hose does not interfere with the movement of the robot and which can reduce the load placed on the robot when it moves while pulling the hose. [Means for solving the problem]

[0010] In order to solve the above problems, a typical configuration of the underwater sediment recovery system of the present invention is an underwater sediment recovery system that recovers and accumulates sediment from a flooded floor, comprising a robot that travels across the flooded floor to suck up the sediment, a discharge nozzle positioned on top of the robot to discharge the sucked up sediment to the outside, and a transport boat that can travel on the water surface of the floor, the transport boat having a bucket with an openable and closable bottom, a float that floats the bucket on the water surface, and a screw that moves the bucket, and the discharge nozzle is installed in a position where it can discharge sediment into the bucket of the transport boat adjacent to the robot.

[0011] In order to solve the above problems, a representative configuration of the underwater sediment recovery method of the present invention is an underwater sediment recovery method that uses the underwater sediment recovery system described above to recover and accumulate sediment from a flooded floor, characterized in that a transport boat is moved below the discharge nozzle of a robot, the robot travels along the floor sucking up the sediment and discharging it into a bucket of the transport boat, the transport boat is moved to a sediment accumulation location, and the bottom of the bucket is opened to release the sediment in the bucket to the accumulation location. Effect of the Invention

[0012] According to the present invention, it is possible to provide an underwater sediment recovery system and an underwater sediment recovery method in which the hose does not hinder the movement of the robot and which can reduce the load placed on the robot when it moves while pulling the hose. [Brief description of the drawings]

[0013] [Figure 1]1 is a schematic diagram of a nuclear power plant building. [Diagram 2] FIG. 2 is an overall perspective view of the robot and the transport boat according to the embodiment. [Diagram 3] 1A to 1C are schematic diagrams illustrating how the recovery robot of the present embodiment travels underwater. [Figure 4] 1 is a schematic diagram illustrating an underwater sediment recovery system according to an embodiment of the present invention. [Diagram 5] FIG. 1 is a diagram illustrating an underwater sediment recovery system according to a comparative example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] A preferred embodiment of the present invention will be described in detail below with reference to the accompanying drawings. The dimensions, materials, and other specific values ​​shown in the embodiment are merely examples for facilitating understanding of the invention, and do not limit the present invention unless otherwise specified. In this specification and drawings, elements having substantially the same functions and configurations are given the same reference numerals to avoid repeated explanations, and elements not directly related to the present invention are not shown.

[0015] (Nuclear Power Plant Building 10) 1 is a schematic diagram of a nuclear power plant building 10. In this embodiment, the nuclear power plant building 10 is exemplified as a facility for collecting sediments, but the present invention is not limited to this. The sediment collection robot according to the present embodiment (hereinafter, referred to as robot 100) can be suitably used in other facilities as long as sediments are accumulated in water.

[0016] As shown in FIG. 1, a nuclear power plant building 10 is a building with multiple floors above ground and multiple floors underground (FIG. 1 illustrates a building with two floors above ground and two floors underground). The 1st floor is the entrance to the ground, and stagnant water is stored on the most underground floor, B2F. To adsorb radioactive materials from the stagnant water, sandbags 12 filled with adsorbent material (e.g., zeolite) are installed on B2F. The robot 100 of this embodiment collects the adsorbent material that has settled in the water as sediment.

[0017] A robot 100 is placed on the B2F of the nuclear power plant building 10. The robot 100 is carried into the B2F by an overhead crane 14 installed on the ceiling of the 1F. When the robot 100 arrives at the B2F, it detaches from the hook 16 and moves underwater on its own. A float cable 18 is connected to the robot 100, and power is supplied from a power supply panel 20, and image data from a camera and signals from various sensors are transmitted to a remote control device 22.

[0018] The overhead crane 14 shown in Fig. 1 carries the robot 100 into and out of the water. In detail, in this embodiment, the robot 100 is carried from the 1st floor to the B2nd floor while suspended from the overhead crane 14. The robot 100 collects sediment while traveling underwater. After the recovery operation, the float cable 18 of the robot 100 is wound by the winding device 24, and the robot 100 is washed by the shower 26, and then the robot 100 is pulled up by the hook of the crane 14 and carried out.

[0019] (Robot 100) 2 is an overall perspective view of the robot 100 and the transport boat 200 of this embodiment. For ease of understanding, the robot 100 used in the underwater sediment recovery system according to this embodiment will be described first.

[0020] 2 travels on a flooded floor (B2F is exemplified in this embodiment) and sucks up sediment that has settled on the floor. The robot 100 includes a robot body 110 capable of travelling underwater, a float 140, a sediment suction mechanism 150, a discharge nozzle 156, a contact mechanism 160, a screw 190, and a robot control unit 102.

[0021] 2, the robot 100 includes a frame 120 and crawlers 130. The frame 120 is made up of an upper frame 122 that constitutes the upper part, and a lower frame 124 that constitutes the lower part. The upper frame 122 is provided with a float 140, and the robot main body 110 is formed on the lower frame 124.

[0022] The robot body 110 has a sediment suction mechanism 150 mounted on the lower frame 124. The sediment suction mechanism 150 is configured to include a suction port 152 and a suction pump 154, and collects sediment from the bottom of the water. The suction port 152 is, for example, a suction nozzle, and is disposed between the crawlers 130 below the robot body 110. The suction pump 154 ​​is connected to the suction port 152 via a connecting hose 154a. As a result, when the suction pump 154 ​​is driven, sediment from the bottom of the water is sucked into the suction port 152 and collected.

[0023] If it is desired to remove the contents of the sediment from the sandbag 12 when the contents are contained in the sandbag 12, the sandbag 12 may be trampled by the crawler 130, the sandbag 12 may be torn, and the contents may then be collected from the suction port 152. Alternatively, a cutting member such as a chip saw may be attached to the front of the lower part of the robot body 110. In this case, the sandbag 12 may be torn using the chip saw, and the contents may be collected from the suction port 152.

[0024] 2, a float 140 is disposed inside the upper frame 122. The float 140 is a hollow housing with air sealed inside. This allows the float 140 to act as a source of buoyancy, making it possible to float the robot 100 in water.

[0025] Electrical components (not shown), such as a circuit board and an imaging device, can be housed inside the float 140. In this embodiment, a robot control unit 102 that is connected to a remote control device 22 (see FIG. 1) and controls the operation of the robot 100 is housed inside the float 140. This makes it possible to effectively prevent breakdowns in the electrical components due to flooding.

[0026] A discharge nozzle 156 is disposed on the upper part of the robot 100, i.e., on the upper frame 122. The discharge nozzle 156 discharges the sediment sucked by the robot 100 (strictly speaking, the sediment suction mechanism 150) to the outside of the robot 100. The discharge nozzle 156 is connected to the suction pump 154 ​​by a connecting hose 158. This maintains the connection between the suction pump 154 ​​and the discharge nozzle 156 even when the upper frame 122 moves toward or away from the lower frame 124 (raising and lowering).

[0027] The robot body 110 and the float 140 described above are connected to each other so as to be able to be attached or detached by a detachment mechanism 160. As shown in Fig. 2, the robot 100 of this embodiment has a screw 190 that propels the robot body 110 in water. For example, a screw integrated with a motor can be suitably used as the screw 190. Fig. 2 shows an example of a configuration in which two screws 190 are arranged on the sides and two screws 190 (one is not visible) are arranged on the rear, but this is not limiting, and the number of screws 190 may be changed as necessary.

[0028] Fig. 3 is a schematic diagram illustrating the robot 100 of this embodiment running underwater. In Fig. 3, the depth of the accumulated water (from the water surface 40a to the water bottom 40b) is assumed to be about 1.5 m. In the robot 100 of this embodiment, during normal running, the attachment / detachment mechanism 160 is extended to separate the float 140 from the robot body 110 as shown in Fig. 3(a). This allows the robot 100 to run on the water bottom 40b by the crawlers 130.

[0029] When the presence of an obstacle 12a ahead is detected, the robot control unit 102 contracts the attachment / detachment mechanism 160. Then, the float 140 approaches the robot main body 110 and the floating body becomes submerged, and the entire robot 100 floats up due to the buoyancy of the float 140.

[0030] Then, with the float 140 in close proximity, the robot body 110 is propelled through the water by the screw 190, thereby climbing over the obstacle 12a as shown in Fig. 3(c) As described above, the robot 100 of this embodiment can climb over the obstacle 12a in the water by utilizing the buoyancy of the float 140, and therefore can efficiently perform the task of recovering sediments in the water.

[0031] In addition, as in the robot 100 of this embodiment, buoyancy acts on the float 140, so that even if the robot 100 tilts in position, it will not fall over and can return to the correct position. Therefore, the position of the robot 100 can be maintained in a stable state.

[0032] (Underwater Sediment Collection System) 4 is a schematic diagram illustrating an underwater sediment recovery system according to this embodiment (hereinafter, referred to as recovery system 100a). In this embodiment, the recovery system 100a will be described in detail, and an underwater sediment recovery method using the same will also be described.

[0033] The recovery system 100a of this embodiment shown in Fig. 4 recovers sediment from a flooded floor (B2F) and accumulates it in an accumulation place P. The recovery system 100a of this embodiment includes the above-mentioned robot 100, a discharge nozzle 156 provided on the robot 100, and a transport boat 200. Note that a detailed explanation of the robot 100 will be omitted, and the details of the discharge nozzle 156 will be described later.

[0034] The transport boat 200 can travel on the water surface 40a of the flooded floor, loads the sediment S sucked up by the robot 100, and transports it to a collection site P. As shown in FIGS. 2 and 4 , the transport boat 200 includes a bucket 210, a float 220, and a screw 230.

[0035] The bucket 210 has an open top and an openable bottom 212 for carrying sediment S. The float 220 is attached to a side 214 of the bucket 210 and provides buoyancy to the bucket 210. The screw 230 is attached to the bucket 210 and is a drive source for propelling the bucket 210 and the transport boat 200. The float 220 enables the transport boat 200 to float on the water surface 40a, and the screw 230 enables the transport boat 200 to travel on the water surface.

[0036] 5 is a diagram illustrating an underwater sediment recovery system of a comparative example (hereinafter, referred to as recovery system 80). Note that common elements between the recovery system 100a of this embodiment and the recovery system 80 of the comparative example are denoted by the same reference numerals, and description thereof will be omitted.

[0037] 5, in the collection system 80 of the comparative example, one collection hole 52 and one transfer hole 60 are formed in the floor 50, and one transfer hose 32 supported by a hose reel 30 is inserted through them. One end of the transfer hose 32 is directly connected to the robot 100, and the other end is disposed in the accumulation location P.

[0038] In a recovery system 80 of a comparative example shown in Fig. 5, a robot 100 travels over the entire flooded floor to recover sediment, and at the same time, transfers the sediment to a collection location P through a transfer hose 32. Because the transfer hose 32 needs to reach the entire flooded floor, its length can be up to 50 m or more, depending on the size of the floor. This places a heavy load on the robot 100 as it moves while pulling the transfer hose 32, and there is a risk that the transfer hose 32 will impede the movement of the robot 100.

[0039] Therefore, in the recovery system 100a of this embodiment, the sediment S is recovered using a robot 100 that travels underwater to suck up the sediment S, and a transport boat 200 that travels on the water surface 40a to transport the sediment S. As a feature of this embodiment, the discharge port 156a of the discharge nozzle 156 of the robot 100 is installed at a position where the sediment S can be discharged into a bucket 210 of the transport boat 200 adjacent to the robot 100.

[0040] When recovering sediment S from a flooded floor, as shown in Fig. 4, the transport boat 200 moves so that the upper surface of the bucket 210 is positioned below the discharge port 156a of the discharge nozzle 156 of the robot 100. At this time, the transport boat 200 is urged toward the robot 100 by the propulsive force of the screw 230, so that the bucket 210 and the discharge port 156a of the discharge nozzle 156 are positioned relative to each other.

[0041] When the transport boat 200 is placed in an adjacent position, the robot 100 travels on the floor, sucking up the sediment S and discharging the sucked up sediment S into the bucket 210 of the transport boat 200. At this time, since the transport boat 200 is biased toward the robot 100, when the robot 100 moves, the transport boat 200 also moves following it. In addition, the bottom surface 212 of the bucket 210 of the transport boat 200 is in a closed state.

[0042] When the sediment S discharged from the robot 100 into the bucket 210 reaches a predetermined amount, the transport boat 200 leaves the robot 100 and moves to a collection location P for the sediment S. The transport boat 200 then opens the bottom surface 212 of the bucket 210 and discharges the sediment S inside the bucket 210 to the collection location P. As a result, the sediment on the flooded floor is collected by the robot 100, transferred (transported) by the transport boat 200, and collected at the collection location P.

[0043] As described above, according to the recovery system 100a of this embodiment and the underwater sediment recovery method using the same, the sediment S sucked up by the robot 100 can be transferred to the accumulation site P without using the transfer hose 32. Therefore, the load of the transfer hose 32 on the robot 100 is reduced, and the transfer hose 32 does not impede the movement of the robot 100. Therefore, the robot 100 can move around the floor appropriately, and the sediment S can be recovered efficiently.

[0044] In this embodiment, the transport boat 200 moves to the collection location P when a predetermined amount of sediment S is loaded in the bucket 210, but the present invention is not limited to this. For example, the transport boat 200 may start moving to the collection location P according to other conditions, such as when the robot 100 discharges the sediment S for a predetermined period of time.

[0045] In addition, in this embodiment, a configuration in which one transport boat 200 is used for one robot 100 is illustrated, but the present invention is not limited to this. For example, multiple transport boats 200 may be used for one robot 100, and the number of robots 100 and the number of transport boats 200 may be appropriately changed as necessary.

[0046] Although the preferred embodiment of the present invention has been described above with reference to the accompanying drawings, it goes without saying that the present invention is not limited to the above-described embodiment. It is clear that a person skilled in the art can think of various modifications or alterations within the scope of the claims, and it is understood that these also naturally belong to the technical scope of the present invention. [Industrial Applicability]

[0047] INDUSTRIAL APPLICABILITY The present invention can be utilized as an underwater sediment recovery system that recovers and accumulates sediment from a flooded floor, and as an underwater sediment recovery method using the same. [Explanation of symbols]

[0048] 10...nuclear power plant building, 12...sandbag, 12a...obstacle, 14...ceiling crane, 16...hook, 18...float cable, 20...power panel, 22...remote control device, 24...winding device, 26...shower, 30...hose reel, 32...transfer hose, 40a...water surface, 40b...water bottom, 50...floor, 52...recovery hole, 60...transfer hole, 80...recovery system, 100...robot, 100a...recovery system, 102...robot control unit, 110...robot body, 12 0...frame, 122...upper frame, 124...lower frame, 130...crawler, 140...float, 150...sediment suction mechanism, 152...suction port, 154...suction pump, 154a...connecting hose, 156...discharge nozzle, 156a...discharge port, 158...connecting hose, 160...detaching mechanism, 190...screw, 200...transport boat, 210...bucket, 212...bottom surface, 214...side surface, 220...floating body, 230...screw, P...accumulation location, S...sediment

Claims

1. 1. An underwater sediment collection system for collecting and accumulating sediment from a flooded floor, comprising: a robot that travels on the flooded floor and sucks up the sediment; a discharge nozzle disposed on an upper portion of the robot for discharging the sucked sediment to the outside; A transport boat capable of traveling on the water surface of the floor; Equipped with The transport boat comprises: A bucket with an openable bottom and A float that floats the bucket on the water surface; A screw that moves the bucket; having The underwater sediment recovery system, wherein the discharge nozzle is installed at a position where the discharge nozzle can discharge the sediment into a bucket of the transport boat adjacent to the robot.

2. 13. An underwater sediment recovery method for recovering and accumulating sediment from a flooded floor using the underwater sediment recovery system according to claim 1, comprising: moving the transport boat under a discharge nozzle of the robot; The robot travels on the floor, sucking up the sediment, and discharging the sucked up sediment into a bucket of the transport boat. moving the transport boat to a collection site for the sediment; A method for recovering underwater sediment, comprising opening the bottom of the bucket and discharging the sediment within the bucket to the collection location.

Citation Information

Patent Citations

  • JP147083A

  • Apparatus and method for recovering sludge

    JP2014125754A