JPH0438332A - dredging equipment - Google Patents

Abstract

PURPOSE:To reduce the cost of spill water treatment by monitoring a signal by a sludge sensor on a dredge, adjusting the height of the whole dredger and covering an inlet-cutter with sludge as much as possible. CONSTITUTION:A sludge collecting plate 11 is disposed onto the outer circumference of a casing 4 so as to cover the outer circumference of an inlet-cutter 5. Auxiliary cutters 11a are arranged on the inner circumferential surface of the sludge collecting plate 11. A support 22 is overhung to the sludge collecting plate 11, and three sludge sensors 20 are fitted to the support 22. When the sludge layer of a thin layer is dredged, the presence of sludge up to the uppermost stage of the multistage inlet-cutters 5 is confirmed by the sludge sensor 20, and dredging work is performed. Accordingly, sludge is introduced into a screw conveyor under the state in which spill water is diminished, thus eliminating the need for spill water treatment, then largely reducing the cost of spill water treatment.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is applicable to dredging, which is used, for example, to dredge soft mud such as sludge accumulated in water intakes of power plants, seabeds, lakes, rivers, ports, etc. It is related to the device.

[Conventional technology] There is a pump type dredging device as a conventional dredging device.

This pump-type dredging device installs a large-capacity pump on a barge or the like, and extends a hose from the pump to the bottom of the ocean, such as the bottom of a lake, and sucks up the soft mud along with the water. The debris dredged in this way is then transported to a landfill, mainly by transport ship. At the landfill, solidifying agents and flocculants are added to solidify the waste.

[Problems to be Solved by the Invention] However, in the conventional dredging equipment described above, the amount of water that is sucked up at the same time as the soft mud is so large that the solidifying agent cannot be mixed until after the surplus water is treated. The drawback is that water treatment requires a lot of money.

[Means for Solving the Problem 1] A vertical screw conveyor, and an inlet cutter rotatably provided at the bottom of the vertical screw conveyor and having a plurality of tomb-shaped inlet cutters spaced apart from each other by an appropriate distance in the vertical direction on the outer peripheral surface. a mud collecting plate having a substantially semicircular cross-sectional shape rotatably disposed around the outer periphery of the inlet device, and a gap between each inlet and the cutter is provided on the inner circumferential surface of the mud collecting plate. This dredging device is equipped with an auxiliary cutter that is protruded between the dredging devices, and is equipped with a soft mud sensor for checking the presence of soft mud on the mud collecting plate.

[Function] In the dredging device of the present invention, after the mud collecting plate is rotated to the back side in the dredging direction so as to face each other, the inlet device is driven to rotate and slowly move forward, thereby solidifying the dredged area with the inlet cutter. The soft mud layer is horizontally sheared, stirred,
It is fluidized and introduced into the interior by the suction force generated by the rotation of the screw of the vertical screw conveyor, and is transported upward by the screw.

At this time, the solidified soft pieces are cut into slices by an inlet cutter, becoming soft and fluidized (but
Foreign matter present in the soft mud cannot pass between the inlet and the cutter and is removed.

The soft mud thus transported upward by the vertical screw conveyor is discharged from the discharge port at the upper end and is transported to the next process.

If the soft mud is hard or sticky, as the operation continues, the soft mud will adhere to the inlet and cutter itself, and this will develop and clog the spaces between the inlets and cutters at each stage, making it difficult for the soft mud to pass through. This will reduce dredging and transportation capacity.

As a countermeasure for such cases, in the present invention, an auxiliary cutter, which is horizontally protruded from the inner peripheral surface of the mud collecting plate and sandwiched between the inlet and the cutter, destroys and removes these clogged solids. There is.

In particular, when dredging a thin layer of soft mud, so-called thin layer dredging, it is necessary to avoid taking in the seawater layer, which is the upper layer of the soft mud layer, into the inside of the inlet device as much as possible. The amount of seawater taken in can be reduced by monitoring the signals from the soft mud sensors installed on the dredging vessel and adjusting the height of the entire dredging device so that the inlet cutter is covered with as much soft mud as possible.

[Embodiments] The present invention will be described in detail below based on embodiments shown in the figures.

1 to 3 relate to an embodiment of the present invention, in which FIG. 1 is an overall vertical cross-sectional view, FIG. 2 is a plan view taken along line 1--2 in FIG. 1, and FIG. 3 is a lower side view.

In the figure, 1 is a vertical screw conveyor, 2 is a casing, 3 is a screw (blade), 3a is a rotating shaft, 3b is an electric motor for driving the screw, 4 is a casing of an inlet device, 5 is an inlet cutter, and 6 is a bearing. , 7 is a girth gear, 8 is a pinion gear, 9 is an electric motor, 10 is a protective cover,
11 is a mud collecting plate, lla is an auxiliary cutter, 12 is a bearing, 13
14 is a chain wheel, 15 is an electric motor, 16 is a protective cover, 20 is a soft mud sensor, and 22 is a support for the sensor dimensions.

As shown in the figure, the vertical screw conveyor l includes a cylindrical casing 2, a screw rotating shaft 3a that is housed inside the casing 2, and is rotationally driven by an electric motor 3b at the top, and screw blades 3. Soft mud such as sludge is lifted up by the screw blade 3 and discharged from the upper discharge port 2a.

On the other hand, below the casing 2 of the vertical screw conveyor 1, a casing 4 of an inlet device that rotates with the same diameter as the casing 2 is suspended via a bearing 6, and an electric motor 9. It can be rotated via a pinion gear 8° and a girth gear 7. At the lower end of the casing 4, an inlet cutter 5 having a tomoe shape as shown in FIG.
Multiple stages are installed on the i5a. As shown in FIG. 2, the inlet cutter 5 is formed into a circular saw-shaped toe shape so as to shear the soft mud layer located on the outer periphery by rotation. In the present invention, the casing 4 and the inlet cutter 5 are collectively referred to as an inlet device.

Further, a substantially circular mud collecting plate 11 is disposed on the outer periphery of the casing 4 so as to cover the outer periphery of the inlet cutter 5 and is supported by a pair of upper and lower bearings 12.
．． It is rotationally driven by an electric motor 15 via 14. 1
6 is a protective cover for the chain wheel. Sludge collection board 11
A flat plate-shaped auxiliary cutter lla is arranged on the inner peripheral surface of the inlet cutter 5 so as to be inserted into the gap between each inlet cutter 5.

11b is a through hole for water passage.

As shown in FIG. 1, the mud collecting plate 11 has a support 22 extending downward from a flange llc at the lower end of the cylinder, and three soft mud sensors 20 are attached to this support 22. Three sensors 20a, 20b, 2
0 c are substantially on the same vertical line, and the lowest end soft mud sensor 20 c is provided slightly below the height of the uppermost inlet cutter 5 . For example, the soft mud sensor model uses a rotary blade that is rotated by a low-torque electric motor, which rotates in running water and stops rotating in soft mud.The presence or absence of soft mud is determined by the rotating or stopped state of the rotary blade. can.

Next, the operation of the dredging device configured as above will be explained.

A dredger equipped with the dredging device of the present invention is transported to a dredging site, stopped, and then adjusted by driving the electric motor 15 so that the mud collecting plate 11 is on the back side in the dredging direction. Thereafter, the vertical screw conveyor 1 is gently lowered until it lands on the seabed. After the inlet device (specifically, the inlet cutter 5) and the mud collection plate 11 have landed and buried in the soft mud layer of the seabed,
When the electric motor 3b is driven to rotate the screw blade 3, and at the same time the electric motor 9 is driven to rotate the inlet cutter 5, the soft layer on the seabed is sheared, stirred, and fluidized, and is successively moved by the suction force generated by the rotation of the screw blade 3. It passes through the opening of the cylinder 5a and enters the device, is transported upward by the screw blades 3, reaches the top of the vertical screw conveyor l, and is discharged from the discharge port 2.
It is discharged from a and transported to the final destination via a pressure pump installed in the next process and a discharge pipe.

Unlike a submersible pump, transportation by the screw blades 3 of the vertical screw conveyor l mainly only vertically transports the solid soft mud without accompanying much liquid.During this time, foreign matter mixed in the soft mud layer is removed. It is blocked by the inlet cutter and prevented from entering the interior.

However, even if there are no foreign substances, solidified soft mud, originally hard soft mud, or highly caking soft mud gradually adheres to the outer periphery of the inlet cutter 5 and develops as the operation continues, and ultimately If the inlet cutter 5 is in close contact with the inlet cutter 5, it may cause clogging. If this condition covers the entire surface of the inlet cutter 5, it becomes difficult for soft mud to pass through, and the amount of mud passing through is extremely reduced, making it difficult to dredge. Capacity is significantly reduced. In order to avoid this situation, an auxiliary cutter lla is always inserted into the gap between each inlet cutter to prevent the formation of clogging.

In particular, when dredging a thin layer of soft mud, if the soft mud sensor 20 (particularly 20c) confirms that the soft mud is present up to the top of the multi-stage inlet cutter 5 before dredging, the soft mud will be dredged. It is advantageous that only soft mud can be taken in without much seawater being involved. In order to confirm that the boundary layer between the soft mud layer and the seawater layer is located at the uppermost inlet cutter 5, the soft mud sensor 20a,
This can be known from the fact that 20b indicates a seawater layer and the soft mud sensor 20c indicates a soft mud layer.

As explained above, according to the present invention, under normal operating conditions, it is possible to transport only soft mud excluding foreign matter at a high concentration and without much surplus water, and to prevent clogging of the inlet cutter. Since an auxiliary cutter is provided, continuous stable operation can be maintained.

[Effect of the invention 1 As described above, according to the present invention, soft mud is introduced into the screw conveyor with surplus water reduced by operating the dredging device while adjusting the height while monitoring with a soft mud sensor. This eliminates the need for surplus water treatment, making it possible to significantly reduce the cost of soft mud treatment.

In addition, since an inlet cutter and a mud collecting plate are provided at the lower end of the vertical screw conveyor, the efficiency of taking in soft mud into the vertical screw conveyor is improved, and since the intrusion of foreign matter can be prevented, the vertical screw In addition to ensuring smooth operation of the conveyor, the auxiliary cutter of the collecting root constantly prevents clogging between the inlet and the cutter, improving maintainability.

[Brief explanation of the drawing]

Figures 1 to 3 show an embodiment of the dredging device of the present invention, where Figure 1 is an overall vertical cross-sectional view, Figure 2 is a plan view taken from Figure 1 - n, and Figure 3 is a lower part of the dredging device. FIG. 1... Vertical screw conveyor, 2...
Casing, 3... Screw blade, 3b.
...Electric motor, 4...Casing of inlet device, 5...
... Inlet cutter, 6 ... Bearing, 7 ... Girth gear, 8 ... Pinion gear, 9 ... Electric motor, 10 ...・Protective cover, 11...-
Sludge collecting plate, 11a...auxiliary cutter, llb...through hole,
12... Bearing, 13... Chain wheel, 14... Chain wheel, 15... Electric motor, 16... Protective cover 20 (20a 20b. 22...Support.

Claims (1)

[Claims] (1) A vertical screw conveyor, and an inlet device including an inlet cutter rotatably installed at the bottom of the vertical screw conveyor and having a plurality of tomb-shaped inlet cutters spaced apart from each other by an appropriate distance in the vertical direction on the outer circumferential surface; A mud collecting plate having a substantially semicircular cross section is rotatably disposed on the outer periphery of the inlet device, and each of the inlets is provided on the inner circumferential surface of the mud collecting plate.
This dredging device is equipped with an auxiliary cutter that projects between the cutters, and is equipped with a soft mud sensor for checking the presence or absence of soft mud on a mud collection plate.