JP5948207B2 - Suction head and sputum method - Google Patents

Description

  The present invention relates to a suction head and a dredging method, and more particularly to a suction head and a dredging method capable of more efficiently pumping sludge accumulated on the bottom of the ground onto the water.

  Sludge containing harmful components may be deposited on the bottom of rivers, lakes and seas. For example, when radioactively contaminated sludge is accumulated on the bottom of the water, it is necessary to lift it onto the water and perform an appropriate purification treatment. Various methods for pulling up the bottom sludge onto the water have been proposed (see, for example, Patent Document 1).

  Patent Document 1 proposes a bottom-bottom harmful substance removal device that arranges a large number of jet nozzles along the inner periphery of a hood portion, generates a water flow toward a suction pump, and pumps sludge onto the water. Specifically, a ring-shaped jet nozzle pipe is installed in the hood, and sludge in the range inside the ring-shaped pipe is wound up by the high-pressure water from the jet nozzle toward the suction port of the suction pump. . The wound sludge is pumped onto the water by suction with a suction pump. In this device, when the ring outer diameter of the ring-shaped pipe increases, the target sludge range becomes excessive, and it is difficult to wind up the sludge sufficiently without generating the water flow by the high pressure water of the jet nozzle as set. There is a problem of becoming.

JP 2007-92410 A

  An object of the present invention is to provide a suction head and a dredging method capable of more efficiently pumping sludge accumulated on the bottom of the ground onto the water.

  In order to achieve the above object, a suction head according to the present invention includes a casing provided with a porous suction port communicating with a suction pump at a central portion of a flat bottom surface, and a suspension portion for engaging a suspension for lifting the casing. And a plurality of plate-shaped guide plates that are curved around the suction port in a plan view and project radially from the bottom surface.

  According to the dredge method of the present invention, the above-described suction head is suspended from a floating body on the water via a suspension member that is locked to the suspension portion, and the suction head is moved downward at a predetermined position and placed on the bottom of the ground. In the state, after the sludge accumulated on the water bottom ground is sucked from the suction port and pumped onto the water through the pumping pipe extending from the casing to the water, the pumping of the sludge at the predetermined position onto the water is finished. The suction head is moved upward through the hanger, moved to another predetermined position without contacting the sludge accumulated on the bottom, and the same procedure is performed on the other bottom at the same position. It is characterized by pumping the accumulated sludge onto the water.

  According to the present invention, when the suction head is placed on the water bottom ground, the sludge accumulated by the guide plate projecting from the bottom surface of the casing is cut and subdivided, so that the sludge easily flows. Become. Further, since a stable water flow is generated along the guide plate, it becomes easy to suck sludge. Furthermore, since the curved flow path is formed along the guide plate, the sludge flow path becomes longer than when the curved path is not curved. As the flow path becomes longer, heavy sand or the like sinks in the process of sucking sludge, and it becomes easy to suck only the sludge to be sucked. In addition, since the guide plate functions as a spacer between the bottom surface of the casing and the water bottom ground, it is advantageous to efficiently suck the sludge having a necessary layer thickness.

It is explanatory drawing which illustrates the state which is implementing the dredging method of this invention. It is explanatory drawing which illustrates the state which is moving the suction head. It is explanatory drawing which illustrates the inside of the suction head of this invention in a longitudinal cross-section. FIG. 4 is a bottom view of the suction head of FIG. 3. It is explanatory drawing which illustrates the suction head of FIG. 4 which is attracting | sucking sludge by bottom view. It is a front view which illustrates another embodiment of a suction head. It is a front view which illustrates another embodiment of a suction head. It is explanatory drawing which illustrates the suction head of FIG. 7 which is attracting | sucking sludge by bottom view.

  The suction head and the scissors method of the present invention will be described based on the embodiments shown in the drawings.

  As illustrated in FIG. 1, the suction head 1 of the present invention is suspended from a floating body 9 over water via a hanging tool 10 such as a wire engaged with a hanging portion 2 b provided in a casing 2. Then, the floating body 9 is moved to a predetermined position along with the movement of the floating body 9 and moved downward at the predetermined position to be placed on the water bottom ground B. A porous suction port 3 is provided on the bottom surface 2 a of the casing 2 of the suction head 1. And the sludge G contaminated by the radioactivity etc. which accumulates on the water bottom ground B is attracted | sucked.

  The suction head 1 is moved up and down by feeding and winding the hoisting tool 10 by the winch 11 installed on the floating body 9. Although the number of the hanging parts 2b can be one, in order to control the posture of the suction head 1, it is preferable to provide a plurality of the hanging parts 2b as in this embodiment and suspend them by a plurality of hanging tools 10. . The float 9 is provided with a line length meter (rotary encoder) 12 for detecting the feeding amount and winding amount of each hanging tool 10. Since the floating body 9 has only a buoyancy on which the winch 11 or the like is mounted and the suction head 1 can be suspended, for example, a small boat or the like can be used.

  As illustrated in FIGS. 3 and 4, the suction head 1 has a hollow casing 2 in which an upper casing 2A and a lower casing 2B are assembled. The casing 2 is circular in plan view, but a quadrangle or other shapes can also be adopted. The outer diameter of the casing 2 is, for example, about 1 m to 4 m with a center of about 1.5 m, but is not limited to this range.

  The bottom surface 2a of the casing 2 is planar. Although the entire range of the bottom surface 2a can be flat, it is preferable that the outer edge of the bottom surface 2a is formed in an arc shape when viewed from the front as in this embodiment. A suction port 3 composed of a large number of through holes 3 a communicating with the suction pump 8 is provided at the center of the bottom surface 2 a. A suction port 3 is connected to the suction side of the suction pump 8 provided in the casing 2, and a pressure feed pipe 7 extending to the water is connected to the discharge side of the suction pump 8.

  In addition, the center part of the bottom face 2a is a range from the center of the bottom face 2a to a predetermined length, and this predetermined length is about 10% to 30% of the outer diameter of the casing 2 (bottom face 2a). Further, the outer edge portion of the bottom surface 2a is a range of a predetermined length or more from the center of the bottom surface 2a, and this predetermined length is about 80% of the outer diameter of the casing 2 (bottom surface 2a).

  As the suction pump 8, a sand pump or a water jet pump can be used. In this embodiment, the suction pump 8 is installed in the casing 2, but the installation position is not limited to this, and the suction pump 8 is installed outside the casing 2, for example, on the floating body 9 or on the land, and attached to the pressure feeding pipe 7. It may be.

  The size of the through hole 3a is, for example, about 10 mm to 50 mm corresponding to the diameter. Although all the through holes 3a can be the same size, it is also possible to mix through holes 3a having different sizes. Although the number of the through-holes 3a is determined suitably, it is about 5-100 pieces, for example.

  The suction head 1 is further provided with a suspension portion 2b for engaging the suspension 10 for lifting the casing 2, and a plurality of plate-like shapes that are curved around the suction port 3 in a plan view and project radially from the bottom surface 2a. A guide plate 4 and a plurality of jet nozzles 5 installed on the bottom surface 2a are provided.

  The guide plates 4 have basically the same specifications, and extend from the center portion (outer edge of the center portion) of the bottom surface 2a to the outer edge portion. In this embodiment, the number of guide plates 4 is twelve, but the number is not limited to this, and is, for example, about four to sixteen. The guide plates 4 are preferably arranged at equal intervals in the circumferential direction, but may be arranged at unequal intervals.

  The height of the guide plate 4 (projection height from the bottom surface 2a) is determined according to the layer thickness of the sludge G to be sucked, and is, for example, about 5 cm to 20 cm, or about 5 cm to 10 cm. The height of the guide plate 4 is constant at least at a position corresponding to the plane of the bottom surface 2a. The height of the guide plate 4 can also be made constant over the entire length in the longitudinal direction.

  The jet nozzles 5 basically have the same specifications. In this embodiment, the number of jet nozzles 5 is six, and every other nozzle plate 5 is disposed between the guide plates 4 adjacent in the circumferential direction. The number of jet nozzles 5 is not limited to this. For example, 2 to 16 jet nozzles 5 are installed according to the number of guide plates 4. It can be arranged between every two guide plates 4 adjacent in the circumferential direction, or can be arranged between all the adjacent guide plates 4. The jet nozzles 5 are preferably arranged at equal intervals in the circumferential direction, but can also be arranged at unequal intervals.

  High-pressure water supplied from a high-pressure water supply source is ejected from the jet nozzle 5, and this ejection direction is a tangential direction with respect to the curved surface of the guide plate 4 in plan view, and the suction port in the tangential direction. It is set on the side facing 3.

  The jet nozzle 5 is preferably installed on the outer peripheral side of the bottom surface 2a as much as possible. In this embodiment, the jet nozzle 5 is installed in the outer edge part of the bottom face 2a, and the ejection direction is set to the circumscribing direction of the arc of the outer edge part in front view. That is, in the front view, it is preferable that the jet direction of the jet nozzle 5 be inclined downward from the horizontal.

  The scissors method of the present invention using this suction head 1 is as follows.

  As illustrated in FIG. 1, the suction head 1 is hung from the floating body 9 via a hanging tool 10 locked to the hanging portion 2 b, and the suction head 1 is moved downward at a predetermined position to the bottom ground B. Place. That is, the suction head 1 is placed on the water bottom ground B without causing the lifting tool 10 to bear the load of the suction head 1.

  In this state, as illustrated in FIG. 3 and FIG. 4, high-pressure water is ejected from the jet nozzle 5, and the sludge G accumulated on the water bottom ground B is sucked from the suction port 3 by suction of the suction pump 8. When the suction head 1 is placed on the water bottom ground B, the accumulated sludge G is cut into pieces and subdivided by the guide plate 4 protruding from the bottom surface 2a of the casing 2. Since the sludge G is subdivided and the formed notch becomes a water flow path, the sludge G easily flows when high-pressure water is ejected from the jet nozzle 5, and the spiral flow centered on the suction port 3. Then the sludge G is sucked.

  The high-pressure water flows along the bottom surface 2a in the front view and flows along the curve of the guide plate 4 in the plan view. Thereby, as illustrated in FIG. 5, the sludge G is mixed with high-pressure water and sucked along the guide plate 4 toward the suction port 3 (through hole 3 a). Since a stable water flow is generated along the guide plate 4, the sludge G is easily sucked.

  Moreover, since the flow path of the sludge G which curved along the guide plate 4 is formed, the flow path of the sludge G becomes long compared with the case where it is not curved. As the flow path becomes longer, heavy sand or the like sinks in the process of sucking the sludge G, and it becomes easier to suck only the sludge G to be sucked.

  Since the guide plate 4 functions as a spacer between the bottom surface 2a of the casing 2 and the water bottom ground B, it is advantageous to efficiently suck the sludge G having a required layer thickness. Therefore, the height of the guide plate 4 is preferably equal to the layer thickness of the sludge G to be sucked.

  Therefore, a set of a plurality of types of guide plates 4 that are detachable and have different heights may be provided on the bottom surface 2a. Among these sets, one type of guide plate 4 having a height closest to the layer thickness of the sludge G to be sucked is selected, and the selected one type of guide plate 4 is protruded from the bottom surface 2a. .

  The sucked sludge G is pumped to the water through the pumping pipe 7 extending from the casing 2 to the water. After the transfer of the sludge G at the predetermined position to the water is completed, the suction head 1 is moved upward to a position where it does not contact the sludge G accumulated on the bottom of the ground B through the suspension 10 as illustrated in FIG. Move. Then, the suction head 1 is moved to another predetermined position, and the sludge G accumulated on the water bottom ground B is pumped onto the water by the same procedure described above at the other predetermined position. In this way, unnecessary diffusion of the sludge G can be prevented by moving the suction head 1 without contacting the sludge G accumulated on the bottom ground B.

  As illustrated in FIG. 6, a flexible skirt portion 6 formed of rubber or the like can be suspended from the outer periphery of the bottom surface 2 a of the casing 2 in the suction head 1. The skirt portion 6 can prevent the sludge G sucked by mixing with high-pressure water from diffusing. The lower end position of the skirt portion 6 may be set to be the same as the lower end position of the guide plate 4. In this embodiment, the skirt portion 6 is formed by arranging a large number of rectangular rubber plates without gaps in the circumferential direction of the casing 2. However, it is also possible to form the skirt portion 6 by winding a single long rubber plate in the circumferential direction.

  As illustrated in FIG. 7, the suction head 1 may be configured so that the jet nozzle 5 described above is not provided. Other configurations are the same as those of the embodiment exemplified above. The dredging method using the suction head 1 of this specification is the same as that of the previous embodiment except that high-pressure water is ejected from the jet nozzle 5. The suction head 1 having this specification is suitable when the sludge G is soft (fluffy sludge G).

  When dredging, the sludge G accumulated on the water bottom ground B is sucked from the suction port 3 by suction of the suction pump 8 with the suction head 1 placed on the water bottom ground B. When the suction head 1 is placed on the water bottom ground B, the accumulated sludge G is cut and subdivided by the guide plate 4. The sludge G is easy to flow due to the subdivision of the sludge G and the formed incision becomes a water flow path. As illustrated in FIG. 8, the sludge G has a spiral flow around the suction port 3. Sludge G is sucked. Since a stable water flow is generated along the guide plate 4, the sludge G is easily sucked.

  In addition, since a curved sludge G flow path is formed along the guide plate 4, the sludge G flow path is longer than when the sludge G is not curved, and heavy sand is contained in the process in which the sludge G is sucked. Etc. sink and it becomes easy to suck only the sludge G to be sucked. Since the guide plate 4 functions as a spacer, it is advantageous for efficiently sucking the sludge G having a required layer thickness.

DESCRIPTION OF SYMBOLS 1 Suction head 2 Casing 2A Upper casing 2B Lower casing 2a Bottom face 2b Suspension part 3 Suction port 3a Through hole 4 Guide plate 5 Jet nozzle 6 Skirt part 7 Pumping pipe 8 Suction pump 9 Floating body 10 Suspension tool 11 Winch 12 Line length gauge B Bottom floor G sludge

Claims (7)

  A casing provided with a porous suction port that communicates with the suction pump at the center of the flat bottom surface, a suspension portion that holds a lifting device that lifts the casing, and a curve centered on the suction port in plan view And a plurality of plate-shaped guide plates projecting radially from the bottom surface.   A plurality of jet nozzles installed on the bottom surface are provided, and the jet direction of the jet nozzles is set on the side toward the suction port in a direction tangential to the curved surface of the guide plate in plan view. The suction head described.   The outer edge portion of the bottom surface is formed in an arc shape when viewed from the front, the jet nozzle is installed at the outer edge portion, and the ejection direction is set to the circumscribing direction of the arc of the outer edge portion when viewed from the front. The suction head described in 1.   The suction head according to any one of claims 1 to 3, further comprising a flexible skirt portion that is suspended from an outer peripheral portion of the bottom surface.   5. The apparatus according to claim 1, further comprising a set of a plurality of types of guide plates that are detachable and have different heights on the bottom surface, and one type of guide plate selected from these sets protrudes from the bottom surface. The suction head described in 1.   The suction head according to claim 1, wherein a suction pump is installed in the casing.   The suction head according to any one of claims 1 to 6 is suspended from a floating body on the water via a suspension member engaged with the suspension portion, and the suction head is moved downward at a predetermined position to be mounted on the water bottom ground. In this state, the sludge accumulated on the water bottom ground is sucked from the suction port and pumped from the casing to the water through the pumping pipe extending on the water, and the pumping of the sludge at the predetermined position onto the water is completed. After that, the suction head is moved upward via the suspension tool, moved to another predetermined position without contacting the sludge accumulated on the water bottom ground, and the water bottom ground in the same procedure at the other predetermined position. A dredging method characterized by pumping sludge accumulated on the water.

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