JP5169558B2 - Classification equipment and classification method - Google Patents

Description

  The present invention relates to a classification facility and a classification method for classifying dredged soil dredged from the bottom of a dam reservoir.

  In general dams, dredging work for discharging mud, earth and sand accumulated at the bottom of the dam is appropriately implemented. Sand material contained in the dredged soil dredged in this dredging work is classified and reused as construction material.

As a method for classifying and collecting sand material from dredged sand, for example, Patent Document 1 discloses a method of classifying dredged sand by providing a classification facility on land. In this method, the dredged sand from the bottom of the dam reservoir is first loaded onto a transport ship, loaded into a settling basin on land, and then ground classification equipment installed adjacent to the settling basin. In addition to dewatering dredged soil, classify and collect sand.
JP 2002-143894 A

  However, the above-described method for collecting sand materials has a problem in that enormous capital investment costs are required because the sand basin and the classification facility are constructed on land.

  Moreover, when the classification equipment provided on land is used, dredged sand is classified into three types: sand, silt, and clay. The classified sand material can be reused at the construction site, but silt and clay must be disposed of as industrial waste, and there is a problem that disposal costs are required.

  Therefore, the present invention has been made in view of the above problems, and an object thereof is to provide an inexpensive classification device and classification method that can collect only sand material from dredged sand.

  In order to achieve the above object, the classification equipment of the present invention is a classification equipment for classifying dredged sand dredged from the bottom of a dam reservoir, wherein a partition wall is installed in the dam reservoir, and the dam uses the partition wall. A water channel formed by partitioning the reservoir, an adjustment means provided at the upstream end of the water channel for adjusting the amount of water flowing into the water channel, and set as a berthing position for a transport ship loaded with dredged sand And a temporary storage place for depositing sand material contained in dredged material sand that has been thrown into the water from the transport ship, directly below the predetermined position. invention).

  According to the classification equipment according to the present invention, since the water channel formed in the dam reservoir and the adjusting means for adjusting the amount of water flowing into the water channel are provided, the flow velocity in the water channel can be controlled. . And since the flow velocity in a water channel is controllable, the sediment contained in dredged sand can be classified using the difference in the sedimentation position by the particle size of the sediment contained in dredged soil.

In addition, since the waterway and the dam reservoir are separated by a partition wall, dredged soil that is thrown into the water does not flow into the dam reservoir during classification.
Furthermore, since the temporary storage place for sand material to accumulate is provided, the sand material after classification can be collected easily.
And since a simple apparatus may be sufficient as a waterway, an adjustment means, and a temporary storage place, capital investment expenses can be reduced compared with the case where large-scale facilities, such as a sand basin and a classification facility, are built on land.

In the present invention, the classification device may further include an unloading means for unloading the sand accumulated in the temporary storage place to the ground.
According to the classifying device of the present invention, the sand material can be pumped to the ground because the carrying means for carrying the sand material to the ground is provided.

  The classifying method of the present invention is a classifying method for classifying dredged sand dredged from the bottom of a dam reservoir. An adjustment means for adjusting the amount of water flowing into the water channel, and a position immediately below a predetermined position set as a anchoring position of the carrier ship loaded with dredged sand. A classifier equipped with a temporary storage for extending sand and contained in dredged sand that has been thrown into the water from the transport ship, and the amount of water flowing into the water channel by the adjusting means is Adjusting the inside of the water channel to a predetermined flow velocity, throwing the dredged sand into the water from the carrier ship anchored at the predetermined position, and the difference in sedimentation position depending on the particle size of the earth and sand contained in the dredged sand Profit And, wherein the depositing only the sand to the temporary field.

  According to the classification method according to the present invention, since the classification equipment including the water channel formed in the dam reservoir and the adjusting means for adjusting the amount of water flowing into the water channel is used, the flow velocity in the water channel is controlled. be able to. And since the flow velocity in a water channel is controllable, the sediment contained in dredged sand can be classified using the difference in the sedimentation position by the particle size of the sediment contained in dredged soil.

In addition, since the waterway and the dam reservoir are separated by a partition wall, dredged soil that is thrown into the water does not flow into the dam reservoir during classification.
Furthermore, since the temporary storage place for sand material to accumulate is provided, the sand material after classification can be collected easily.
And since simple classification equipment is used, capital investment cost can be reduced compared with the case where large-scale equipment, such as a sand basin and classification equipment, is built on land.

  According to the transport ship of the present invention, dredged sand can be classified with inexpensive equipment, and only sand material can be easily collected from the classified sediment.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is an overall schematic diagram showing a classification facility 1 according to the first embodiment of the present invention, and FIG.

As shown in FIGS. 1 and 2, the classification facility 1 includes a water channel 3 formed in the dam reservoir 2, and adjusting means for controlling the flow rate in the water channel 3 by adjusting the amount of water flowing into the water channel 3. 4, a sign 6 indicating a position where the carrier 5 loaded with dredged sand is anchored, a temporary storage 8 for depositing sand material 7 contained in dredged sand put into the water from the transport 5, and a temporary storage 8 And an unloading means 9 for unloading the accumulated sand material 7 to the ground.
The water channel 3 is formed by installing a partition wall 10 in the dam reservoir 2 and partitioning the dam reservoir 2 by the partition wall 10.
The partition wall 10 is installed along the shape of the shore so that the width of the water channel 3 is substantially the same over its entire length. Therefore, the flow velocity of the water flowing in the water channel 3 is almost constant over the entire length.

3 and 4 are an enlarged plan view and a side view of a part of the partition wall 10 according to the present embodiment.
As shown in FIG. 3 and FIG. 4, the partition wall 10 is placed on the bottom plate of the dam reservoir 2 at a predetermined interval and supports the water shield 11 by partitioning the dam reservoir 2 and the water channel 3. It is comprised from the steel pipe pile 12 to do.

A plurality of ring-shaped fasteners 13 are attached to one surface of the water shielding material 11. The water shielding material 11 is attached to the steel pipe pile 12 by passing the steel pipe pile 12 through the fastener 13. In the present embodiment, a nylon water shielding sheet is used as the water shielding material 11. In the present embodiment, a nylon water-impervious sheet is used as the water-impervious material 11. However, the present invention is not limited to this material, and a polyester water-impervious sheet may be used.
Moreover, in this embodiment, although the partition wall 10 comprised from the steel pipe pile 12 and the water-impervious material 11 was demonstrated, it is not limited to this, A some steel pipe sheet pile is connected and the partition wall 10 is connected. In other words, the partition wall 10 may be formed.

5 and 6 are a front view and a side view showing the adjusting means 4 according to the present embodiment.
As shown in FIGS. 5 and 6, the adjusting means 4 measures a gate 14 provided at the upstream end of the water channel 3, a lifting device 15 for lifting and lowering the gate 14, and a flow velocity in the water channel 3. It consists of an anemometer 16 (see FIG. 1).
The gate 14 includes a plurality of steel pipe piles 17 placed on the bottom plate of the dam reservoir 2 and a flow rate adjusting material 18 that can be moved up and down along the steel pipe piles 17.

  In the present embodiment, the same water-proof sheet made of nylon as the water-blocking material 11 is used as the flow rate adjusting material 18. As with the water shielding material 11, a plurality of ring-shaped fasteners 19 are attached to one surface of the flow rate adjusting material 18, and the steel pipe pile 17 is passed through the ring-shaped fastener 19, thereby allowing The adjusting material 18 is attached to the steel pipe pile 17. Since the diameter of the fastener 19 is slightly larger than the diameter of the steel pipe pile 17, a gap is formed between the fastener 19 and the steel pipe pile 17, and the flow rate adjusting material 18 can be moved up and down along the steel pipe pile 17. It is.

  In the present embodiment, a nylon water-impervious sheet is used as the flow rate adjusting member 18, but the present invention is not limited to this, and for example, a plate-like member such as iron or vinyl chloride may be used.

  The elevating device 15 includes a wire rope 20 having one end connected to the flow rate adjusting material 18 and a winch 21 for moving the flow rate adjusting material 18 up and down by winding and unwinding the wire rope 20.

  The amount of water flowing into the water channel 3 can be increased by winding the wire rope 20 with the winch 21 and moving the flow rate adjusting member 18 upward. On the other hand, the amount of water flowing into the water channel 3 can be reduced by feeding the wire rope 20 with the winch 21 and moving the flow rate adjusting member 18 downward.

The anemometer 16 is installed in the vicinity of a predetermined position 22 where the transport ship 5 is anchored and dredged sand is introduced.
In the water channel 3, the flow rate near the predetermined position 22 is measured by the anemometer 16, and the flow rate adjusting material 18 is adjusted to rise and fall to a predetermined value (details will be described later) determined by design and the like. To be controlled.

  Specifically, when the flow velocity in the dam reservoir 2 is faster than the predetermined flow velocity, the flow rate adjusting material 18 is moved downward to decrease the flow velocity in the water channel 3. Moreover, when the flow velocity in the dam reservoir 2 is slower than a predetermined flow velocity, the flow rate adjusting material 18 is moved above the water surface to increase the flow velocity in the water channel 3.

  Referring again to FIG. 1, the sign 6 is a buoy that can float on water, and a plurality of signs 6 are installed so as to surround the transport ship 5. The range surrounded by these buoys is the predetermined position 22, and the transport ship 5 is anchored at this position, and dredged sand is thrown in.

  The temporary storage place 8 (see FIG. 2) is provided on the bottom of the water so as to extend downstream from a predetermined range surrounded by buoys. The length of the temporary storage 8 extending downstream is a range in which the sand material 7 to be collected is allowed to flow at a predetermined flow rate at a predetermined time, and is determined by design or the like (details will be described later) To do).

FIG. 7 is a conceptual diagram showing the subsidence state of silt 23, clay 24, and sand material 7 included in dredged sand put into water from transport ship 5.
As shown in FIG. 7, among the sand contained in dredged sand that has been thrown into the water from the transport ship 5, sand material 7 having a large particle size is located immediately below the loading position and on the temporary storage place 8 on the slightly downstream side. To deposit. On the other hand, the silt 23 and the clay 24 having a small particle diameter are caused to flow downstream from the temporary storage place 8 and settle to the bottom of the water channel 3 where the temporary storage place 8 is not installed.
In addition, the pollution prevention film | membrane 25 is installed in the downstream edge part of the water channel 3, and it prevents that the silt 23 and the clay 24 which did not settle spread in the dam reservoir 2. FIG.

FIG. 8 is a view showing the carry-out means 9 according to the present embodiment.
As shown in FIG. 8, the carry-out means 9 includes a work table 26 provided so as to project from the land into the dam reservoir 2, a crawler crane 27 that can travel on the work table 26, and a wire of the crawler crane 27. A grab bucket 29 is connected to the rope 28 and can move in the vertical direction by winding and unwinding the wire rope 28.
The sand material 7 accumulated in the temporary storage 8 is gripped by the grab bucket 29 and sanded on land. The sand material 7 that has been sanded is transported to a construction site such as a landfill by a truck and reused.

Next, the result of examining the width and installation depth of the temporary storage place 8 and the flow velocity in the water channel 3 when the classification facility 1 according to the present invention is applied using a certain dam reservoir 2 as a model will be described below.
In this embodiment, the sand material 7 to be collected is a particle having a particle size of 0.15 mm or more among the earth and sand contained in dredged sand. It is desirable to remove silt 23 and clay 24 having a particle size of 0.075 mm or less, and to remove earth and sand having a particle size larger than 0.075 mm and smaller than 0.15 mm. In the case of being mixed in 7, the sample was collected as it was.

FIG. 9 is a diagram illustrating an example of a result of calculating the sedimentation speed of the sand material 7, the silt 23, and the clay 24 included in the dredged sand.
As shown in FIG. 9, the time required for the sand material 7 of 0.15 mm or more to settle to 5 m, 10 m and 20 m is 0.057 hours (≈3 minutes) and 0.115 hours (≈7 minutes), respectively. 0.229 hours (≈14 minutes). The time required for the silt 23 or clay 24 of 0.075 mm or less to settle down to 5 m, 10 m, and 20 m is 0.330 hours (≈20 minutes) and 0.660 hours (≈40 minutes), respectively. 319 hours (≈80 minutes).

Next, the flow velocity in the water channel 3 and the width of the temporary storage place 8 will be examined.
For example, assuming that 9893 m ³ / min (measured value of a certain dam reservoir 2) flows into the dam reservoir 2 having a width of 300 m and a water depth of 20 m, the flow velocity V1 (m / min) in the dam reservoir 2 is ( 1)
V1 = 9893 / (300 × 20)
= 1.65 (1)

When dredged sand is thrown into the dam reservoir 2 at the flow velocity V1, the sand material 7 contained in the dredged sand settles toward the temporary storage site 8 and also moves downstream. The movement distance L1 (m) for moving to the downstream side during the 14 minutes until the sand material 7 reaches the temporary storage place 8 installed at a water depth of 20 m is expressed by equation (2).
L1 = 1.65 × 14
= 23.1 (2)

  When the sand material 7 moves 23.1 m downstream, in order to collect the sand material 7, the temporary storage place 8 must be extended from the position just below the dredged sand loading position to 23.1 m downstream. However, if the temporary storage 8 is provided as much as 23.1 m on the downstream side, the construction cost is high and the moving range of the crawler crane 27 used for the unloading work is widened and the work efficiency is deteriorated. desirable.

Therefore, the moving distance L2 (m) of the sand material 7 for 14 minutes when the flow velocity is set to 1.0 m / min so that the length of the temporary storage place 8 is shortened is expressed by Equation (3).
L2 = 1.0 × 14
= 14 (3)
The extra length 1 m was added to the moving distance 14 m of the sand material 7 calculated from the equation (3), and the length in the downstream direction of the temporary storage 8 was set to 15 m. And the upper limit of the flow velocity was 1.0 m / min.
Moreover, the length of the temporary storage 8 in the width direction was set to 10 m in consideration of the length of the boom 30 of the crawler crane 27.

  Next, the case where the lower limit value of the flow velocity was set to about 1/3 and 1/2 of the upper limit value of 1.0 m / min, 0.3 m / min and 0.5 m / min was examined.

The 14-minute moving distance L3 (m) of the sand material 7 when the flow rate is 0.3 m / min is expressed by the following equation (4).
L3 = 0.3 × 14
= 5.2 (4)
Further, the 14-minute moving distance L4 (m) of the sand material 7 when the flow velocity is 0.5 m / min is expressed by equation (5).
L4 = 0.5 × 14
= 7.0 (5)
When the flow rate is 0.3 m / min, the moving distance of the sand material 7 is 5.2 m as shown in the equation (4), and when the flow rate is 0.5 m / min, the sand as shown in the equation (5) The moving distance of the material 7 is 7.0 m. Therefore, since the sand material 7 can be deposited on the temporary storage place 8 in both cases, any flow rate may be used. In addition, the upper limit value and the lower limit value of the flow velocity are appropriately adjusted according to the size of the temporary storage place 8.

  Next, a second embodiment of the present invention will be described. The gate 31 of the second embodiment adjusts the flow velocity in the water channel 3 by rotating the gate 31. In the following description, portions corresponding to the first embodiment are denoted by the same reference numerals, description thereof is omitted, and differences are mainly described.

FIG.10 and FIG.11 is the side view and top view which show the adjustment means 32 which concerns on 2nd embodiment of this invention.
As shown in FIGS. 10 and 11, the adjusting means 32 includes a gate 31 provided at the upstream end of the water channel 3, a rotating device 33 for opening and closing the gate 31, and the anemometer 16. .

The gate 31 includes a plurality of steel pipe piles 34 placed on the bottom plate of the dam reservoir 2 and a steel plate 35 attached to the outer peripheral surface of each steel pipe pile 34.
The steel pipe pile 34 is installed to be rotatable in the circumferential direction around the axis.

  The rotating device 33 includes a motor 36 provided on the ground, a gear 37 installed at the upper end of each steel pipe pile 34, and a belt 38 that transmits the rotation of the motor 36 to each gear 37. By driving the motor 36 and rotating the gears 37 via the belt 38, all the steel pipe piles 34 can be rotated by the same angle. When the steel pipe pile 34 rotates, the steel plate 35 also rotates at the same time, and the amount of water flowing into the water channel 3 can be controlled.

  According to the classification facility 1 in each embodiment described above, the water channel 3 formed in the dam reservoir 2 and the adjusting means 4 and 32 for adjusting the flow velocity in the water channel 3 are provided. It is possible to classify dredged soil using the difference in sedimentation position depending on the particle size of the contained sediment.

Further, since the water channel 3 and the dam reservoir 2 are separated by the partition wall 10, dredged sand put into the water channel 3 does not flow out into the dam reservoir 2 when classification is performed.
And since the adjustment means 4 and 32 are provided, the flow rate can be adjusted suitably according to the particle size distribution of dredged sand.
Furthermore, since the temporary storage place 8 for depositing the sand material 7 is provided, the sand material 7 after classification can be easily collected.

Moreover, since the silt 23 and the clay 24 are deposited on the bottom of the downstream water channel 3, it is not necessary to dispose the silt 23 and the clay 24.
And since the water channel 3, the adjustment means 4 and 32, and the temporary storage place 8 may be a simple apparatus, compared with the case where large-scale facilities, such as a sand basin and a classification facility, are built on land, capital investment expense can be reduced. it can.
Since the carrying means 9 for carrying the sand material 7 deposited in the temporary storage place 8 to the ground is provided, the sand material 7 can be easily sanded to the ground.

It is a whole schematic diagram showing classification equipment concerning a first embodiment of the present invention. It is an AA arrow line view of FIG. It is the top view to which a part of partition wall concerning this embodiment was expanded. It is the side view which expanded a part of partition wall concerning this embodiment. It is a front view which shows the adjustment means which concerns on this embodiment. It is a side view which shows the adjustment means which concerns on this embodiment. It is a conceptual diagram which shows the subsidence state of the silt, clay, and sand material which are contained in dredged material sand thrown into water from the transport ship. It is a figure which shows the carrying-out means which concerns on this embodiment. It is a figure which shows the example of the result of having calculated the sedimentation rate of the sand material, silt, and clay contained in dredged soil. It is a side view which shows the adjustment means which concerns on 2nd embodiment of this invention. It is a top view which shows the adjustment means which concerns on 2nd embodiment of this invention.

Explanation of symbols

1 Classifying Equipment 2 Dam Reservoir 3 Water Channels 4 and 32 Adjusting Means 5 Carrying Ship 6 Marking 7 Sand Material 8 Temporary Place 9 Unloading Means 10 Partition Wall 11 Water Impermeable Materials 12, 17, 34 Steel Pile 13, 19 Fastener 14 Gate 15 Lift 16 Current meter 18 Flow rate adjusting material 20, 28 Wire rope 21 Winch 22 Predetermined position 23 Silt 24 Clay 25 Pollution prevention film 26 Work table 27 Crawler crane 29 Grab bucket 30 Boom 31 Gate 33 Rotating device 35 Steel plate 36 Motor 37 Gear 38 Belt

Claims (3)

A classifying facility that classifies dredged soil from the bottom of the dam reservoir,
A water channel formed by installing a partition wall in the dam reservoir and partitioning the dam reservoir with the partition wall;
Adjusting means for adjusting the amount of water that is provided at the upstream end of the water channel and flows into the water channel;
Temporary storage area for depositing sand material contained in dredged sand that extends from directly below a predetermined position set as a anchoring position of the transport ship carrying the dredged sand and is thrown into the water from the transport ship Classifying equipment characterized by comprising.   The classification equipment according to claim 1, further comprising unloading means for unloading the sand accumulated in the temporary storage area to the ground. In the classification method to classify dredged soil dredged from the bottom of the dam reservoir,
A partition wall is installed in the dam reservoir, and the water channel formed by partitioning the dam reservoir with the partition wall and an upstream end of the water channel, and adjusts the amount of water flowing into the water channel And a sand material contained in dredged sand that has been extended from directly below a predetermined position set as a berthing position of a carrier ship loaded with dredged sand and poured into water from the carry ship. Using a classification facility equipped with a temporary storage place to deposit,
The amount of water flowing into the water channel is adjusted by the adjusting means, the inside of the water channel is set to a predetermined flow velocity,
Throwing the dredged sand into the water from the carrier ship anchored at the predetermined position,
A classification method characterized in that only the sand is deposited in the temporary storage site by utilizing the difference in the settling position depending on the particle size of the earth and sand contained in the dredged soil.

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