JP2000144796A - Device and method of dehydrating dredged material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device and a method of dehydrating a dredged material for providing the optimal dredged material for reclamation at a low cost. SOLUTION: A spiral agitating blade 2 is installed integrally into an agitating tank and a hollow passage 23, into and from which a dredged material is entered and discharged while being agitated, is formed, the agitating tank is placed on a revolving roller mounted on the upper section of a cradle, and a gear chain is stretched on a gear and a wheel set up to the central outer circumferential surface section of the agitating tank. A filter screen 4 is fixed into a cover detachably attached at the front end section of the agitating tank, the front end section of a hose 5 is connected to a vacuum pump 15 and the revolving roller fitted to the projecting shaft of the upper section of an upright lever 13 is fitted movably to the rear-section ring of the agitating tank. The dredged material after a moisture is to some extent removed by settling and separation is charged into the agitating tank at that time, the inside of the agitating tank is brought to a vacuum state by the vacuum pump while agitating the dredged material by rotating the agitating tank, and moisture in the dredged material is removed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dredged soil dewatering apparatus and method, and more particularly, to a dredged soil dewatering apparatus and method for inexpensively providing an optimum dredged soil for landfill.

[0002]

2. Description of the Related Art When constructing a landfill site for developing a resort or constructing a new airport, for example, when compacting a bank or a subgrade roadbed, a density such as rolling pressure or vibration is applied to artificially increase the density. This results in tighter interstices between the particles, better engagement, increased adhesion and increased stability. How to compact the soil at this time
It is necessary to adjust the water content to the most appropriate one because it varies greatly depending on the soil content, grain size and water content.

[0003] Conventionally, earth and sand for land reclamation is obtained by rubbing the earth and sand on the sea floor with a dredging machine, and using a pump to move a float crawling on the sea through a pipe provided on the side to a sediment storage site provided on land. It is transported and then obtained by removing the water content in the sediment by sedimentation separation, and the obtained soil is transported to a predetermined place for landfill and compaction. Alternatively, a landfill has been provided in a landfill, and landfilling has been performed by directly compacting the soil from which water has been removed by sedimentation and separation.

[0004]

However, the dredged soil is firmly compacted and stable because only a short period of sedimentation and separation can not sufficiently remove the water content of the earth and sand including the slime and organic matter. Required too long a period of time, and was not in time for the landfill planning period, and had problems that were unrealistic.

Therefore, there is a method of placing the dredged soil obtained by the above-mentioned method on a belt conveyor and applying hot air to the dredged soil to remove moisture. However, in this method, a large amount of electric power is required to generate hot air. Since it is necessary and the utility cost is too high, it is hardly implemented practically. Therefore, at present, the method of adding cement or chemical agent to dredged soil to remove water and compact quickly is generally performed.
The amount of cement and chemicals to be added to the dredged soil is excessively large, and as a result, the cost is high and the economic burden is inevitable.

[0006]

Means for Solving the Problems The present invention has been made to solve the above-mentioned problems, and the gist of the present invention is that a spiral stirring blade is integrally provided in a stirring tank to reduce dredged soil. Form a hollow passage that enters and exits while being stirred, place the stirring tank on a rotating roller mounted on the upper part of the receiving table, and secure it by fitting it into a gear and a drive motor shaft provided circumferentially on the center outer peripheral surface of the stirring tank. A gear chain is hung on the large gear and the filter net is fixed in a lid detachably attached to the tip of the stirring tank,
Further, the front end of the hose was loosely fitted to the mouth of the lid via an O-ring, and the rear end was connected to a vacuum pump. Then, the hose was rotatably fitted to the projecting shaft on the upper part of the upright rod at the rear of the cradle. A dredging soil dewatering device capable of removing water from the dredged soil, wherein the rotating roller is loosely fitted to the rear ring of the stirring tank,
The dredged soil from which water has been removed to some extent by sedimentation and separation is put into a stirring tank provided with stirring blades, and the inside of the stirring tank is evacuated with a vacuum pump while stirring the dredged soil by rotating the stirring tank. Thus, there is provided a method for dewatering dredged soil, characterized in that moisture in the dredged soil can be removed. Next, embodiments of the present invention will be described with reference to the drawings.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1 and FIG. 2, reference numeral 1 denotes a rectangular metal stirring tank having a ring 14 projecting from the rear center thereof. The wing 2 is provided integrally, and a hollow passage 23 is formed. Reference numeral 3 denotes a lid detachably attached to the front entrance of the stirring tank 1, and a filtration net 4 is fixed to the inside of the rear of the lid 3. Reference numeral 5 denotes a flexible hose. The tip of the hose 5 is loosely fitted to the mouth 6 of the lid 3 via O-rings 7 and 7, and the rear end of the hose 5 is connected to a vacuum pump 15. Have been. Reference numeral 8 denotes a support for the agitation tank 1 in which an upright rod 13 is vertically provided at the rear and integrally provided. A drive motor 9 is provided at the center of the support 8, and a shaft of the drive motor 9 is provided. The large gear 10 is fitted and fixed to 22.

Reference numerals 11 and 12 denote rotating rollers mounted on support shafts 20 and 21 provided on both front and rear sides of the receiving table 8, respectively. The stirring tank 1 is placed on the rotating rollers 11 and 12, and the rotation of the stirring tank 1 is smoothly performed by the rotating rollers 11 and 12. Reference numeral 16 denotes a protruding shaft that protrudes from the upper part of the upright rod 13 of the receiving table 8 into the ring 14 of the stirring tank 1.
Are rotatably fitted, and the rotating roller 16 is fitted and fixed in the ring 14. Reference numeral 18 denotes a circumferential gear provided on the central outer peripheral surface of the stirring tank 1. A gear chain 19 is hung on the gear 18 and the large gear 10 fixedly fitted to the motor shaft 22 of the drive motor 9. I have.

In order to dewater the dredged soil using the dewatering device of the present invention, first, the lid 3 which can be freely attached and detached is opened, and the dredged soil conveyed by a belt conveyor or the like is introduced into the stirring tank. When the loading of the dredged soil is started, the drive motor 9 is started and the large gear 10 is rotated in the direction of arrow X in FIG. Then, as the gear 10 rotates, the gear 10
When the gear chain 19 hung on the gear of the stirring tank starts rotating, the stirring tank starts rotating in the arrow X direction. At this time, the rotation of the stirring tank 1 is smoothly performed by the rotation of the rotating rollers 11 and 12 provided at a total of four places on the receiving table 8.

When the rotation of the stirring tank starts, the spiral stirring blades 2 are provided in the stirring tank 1, so that the dredged soil passes through the hollow passage 23 while rotating the stirring blades 2 in the arrow X direction. And is pushed backward in the stirring tank 1.
By rotating the stirring tank 1 in this way, the dredged soil is injected while being pushed to the rear of the stirring tank 1. After completion of charging a predetermined amount of dredged soil, rotation of the stirring tank 1 is stopped and the lid 3 is closed. When the lid 3 is closed, the stirring tank 1 is rotated again in the direction of arrow X, and the vacuum pump 15 is started to activate the vacuum pump 1.
By the start of 5, the inside of the stirring tank 1 gradually becomes a vacuum state,
Since the dredged soil is agitated, the moisture contained in the dredged soil evaporates evenly. At this time, the vacuum pump 15 removes the air by sucking the air in the stirring tank 1 to make the inside of the stirring tank 1 a vacuum state. Therefore, the dredged soil is drawn into the vacuum pump 15 together with the air. A filter net 4 is provided on the inner part of the lid 3 so as not to cause it.

After a predetermined time has elapsed since the vacuum pump 15 was activated and brought into a vacuum state, the rotation of the stirring tank 1 is stopped.
After the start and stop of the vacuum pump 15, the lid 3 is opened. After the lid 3 is opened, the drive motor 9 is started in the reverse direction, and the large gear 10 is rotated in the direction of arrow Y in FIG. Then, as the gear 10 rotates, the gear 10
When the gear chain 19 engaged with the gear chain 19 starts rotating, the stirring tank starts rotating in the arrow Y direction by the gear 18 meshing with the gear chain 19. When the rotation starts, the dredged soil is gradually transferred to the front of the stirring tank 1 by the rotation of the stirring blade 2 in the direction of the arrow Y while passing through the hollow passage 23, and the lid 3 is finally removed to be open. From the front of the stirring tank 1,
Dredged soil after dewatering is discharged to the outside.

[0012]

[Embodiment 2] In order to obtain earth and sand having an appropriate amount of water for landfill construction using the above-mentioned dewatering device, first, sand on the seabed is dredged by a dredger and then pumped. Then, the float crawling on the sea is transported through a pipe provided on the side to a sediment temporary storage site provided on land, and thereafter, moisture contained in the sediment is removed by sedimentation separation. Next, while rotating the stirring tank 1 in the direction of the arrow X in FIG. After the feeding to the predetermined amount is completed, the cover 3 is closed, and the arrow X
While rotating in the direction, the vacuum pump 15 is started, and the inside of the stirring tank 1 is evacuated to dehydrate the dredged soil. After a predetermined period of time, the vacuum pump 15 is released, the vacuum pump 15 is stopped, and the lid 3 is opened. Next, by rotating the stirring tank 1 in the arrow Y direction in FIG. 1, the dredged soil moves forward by the rotation of the stirring blade 2 in the arrow Y direction while passing through the hollow passage 23, and is sequentially discharged from the stirring tank 1. .

[0013]

As described above, the dewatering device of the present invention is provided with a spiral stirring blade in the stirring tank, so that dredged soil can be easily taken in and out only by changing the rotation direction of the stirring tank. In addition, because the stirring blade efficiently stirs the dredged soil,
Dewatering of dredged soil is performed evenly. When the inside of the stirring tank was evacuated and the dredged soil was dewatered, the filter net was fixed to the lid, so that the dredged soil was drawn into the vacuum pump together with the air so that the vacuum pump did not break down. Further, since the stirring tank rotates while the load of the stirring tank is supported by the rotating roller provided on the receiving table, the rotation of the stirring tank is performed smoothly.

Further, since the dehydration method of the present invention is as described above, a large amount of electric power is not required unlike the conventional hot air drying, and a huge amount of cement and chemicals are not used, so that the cost can be reduced and the landfill can be performed. The dredged soil having an optimal water content for use can be provided at low cost.

[Brief description of the drawings]

FIG. 1 is a reference longitudinal sectional view of a dehydrating apparatus of the present invention.

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

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Stirring tank 2 Stirrer blade 3 Lid 4 Filtration net 5 Hose 6 Mouth 7 O-ring 8 Cradle 9 Drive motor 10 Large gear 11, 12 Rotary roller 13 Upright rod 14 Ring 15 Vacuum pump 16 Rotary roller 17 Projection shaft 18 Gear 19 Gear chain 20, 21 Support shaft 22 Motor shaft 23 Hollow passage

Claims (2)

[Claims] 1. A spiral stirring blade is integrally provided in a stirring tank to form a hollow passage through which dredged soil enters and exits while being stirred, and the stirring tank is placed on a rotating roller mounted on an upper portion of a receiving table. , A gear chain is hung on a gear provided circumferentially on the center outer peripheral surface of the stirring tank and a large gear fitted and fixed on the drive motor shaft, and a filter net is fixed in a lid detachably attached to the tip of the stirring tank. Then, the front end of the hose is loosely fitted to the mouth of the lid via an O-ring, and the rear end is connected to a vacuum pump. A dredged soil dewatering device for removing water from a dredged soil, wherein the worn rotating roller is loosely fitted to a rear ring of the stirring tank. 2. In order to provide an optimum dredged soil for landfill, the dredged soil after removing water to some extent by sedimentation and separation is put into a stirring tank provided with a stirring blade, and the stirring tank is rotated. A method for dewatering a dredged soil, wherein the inside of a stirring tank is evacuated by a vacuum pump while stirring the dredged soil to remove moisture in the dredged soil.