JPH0226699A - Method and apparatus for dehydrating soil with high water content - Google Patents

Abstract

PURPOSE:To dehydrate the whole of soil to be dehydrated efficiently and uniformly by a method wherein an airtight box body having strainer pipes mounted thereto so as to be turned downwardly is moved and positioned by a transport and press-in machine to be introduced in the soil with high water content of a dehydration tank under pressure and, after dehydration treatment is performed under vibration and vacuum suction, said box body is again positionally changed to repeat the same process. CONSTITUTION:In a dehydration apparatus equipped with a vibrator, an airtight box body 6 having strainer pipes provided thereto so as to protrude downwardly is moved and adjusted up and down or left and right by a transport and press-in machine 8 and allowed to fall at a predetermined position to be introduced in the soil with high water content thrown in a dehydration tank 4 from the upper opening part thereof under pressure. The dehydration tank 4 is vibrated before and after the airtight box body 6 and the strainer pipes are introduced under pressure and the moisture in the soil with high water content is exuded and released to be discharged to the outside by a vacuum pump 11. After this dehydration treatment, the airtight box body 6 and the strainer pipes are again pulled out by the transport and press-in machine 8 to be moved to a separate position to repeat the same dehydration process over the whole of the soil to be dehydrated.

Description

[Detailed Description of the Invention] "Industrial Application Field" The present invention relates to a method and apparatus for dehydrating high-responsive soil such as sludge and excavated mud using the mud water shield method to lower the water content ratio. It is.

"Prior art, problems to be solved by the invention" Generally,
Many of the residual soils discharged from civil engineering works, such as clayey soil containing silt from excavations, sludge from dredging, and excavated mud from the muddy water shield method, have extremely high water content.
Such highly water-containing soil is treated as industrial waste, and in order to dispose of it, it is necessary to reduce the water content at least and treat it as leftover soil.

Conventional methods for treating soil with high moisture content include mixing and stirring solidification agents such as cement and lime, but in order to treat large amounts of soil with high moisture content, the material cost of the solidification agent has to be increased. However, when a strong alkaline material such as cement, which is inexpensive, is used as a solidifying material, there is a problem of alkaline contamination.

In addition, by placing high water content soil in a conventional underground drainage pit and draining the water into a bottom filtration layer made of crushed stones or mesh pipes, and pumping it up with a water absorption pipe, the water content ratio can be lowered to normal. A method of disposing of soil as residual soil is also known, but since this method uses natural gravity drainage, there are problems such as the long drainage distance and time, which is inefficient, and the filter tank is easily clogged, making maintenance difficult. was there.

``Means for Solving the Problems'' In order to solve the above-mentioned conventional problems, the present invention provides an airtight box attached to a conveying and press-fitting machine that can move vertically and horizontally into highly water-containing soil put into a dehydration tank. At the same time, a strainer tube protruding downwards is inserted into the airtight box, and the dewatered soil is vibrated by a dewatering tank or a vibrator attached to the top of the airtight box. By applying water to exude water, and then vacuuming this water through a strainer tube and discharging it to the outside, the water in highly water-containing soil can be efficiently dehydrated and economically treated as normal residual soil with a lower water content ratio. In addition, the present invention proposes a method and apparatus that can efficiently dewater a large amount of highly water-containing soil while sequentially moving the penetration position of the airtight box using a transport press-in machine.

In addition, this invention provides a part of the peripheral wall of the dewatering tank with a soil discharge port that can be opened and closed, and by making the dewatering tank rotatable with the soil discharge port facing downward, the remaining soil after dewatering is automatically removed from the dewatering tank. The purpose of this paper is to propose a device that can efficiently discharge wastewater.

Furthermore, this invention reduces clogging by making the strainer pipe a double porous pipe with inner and outer layers, and by inserting and removing a fine water permeable material between the inner and outer porous pipes. The present invention proposes a device that allows the water-permeable material to be easily cleaned or replaced.

"Embodiments" Below, embodiments of the present invention shown in the drawings will be described.
Figures 1 to 7 show the dewatering apparatus and dehydrating method of the present invention, in which a shaker is placed inside the base l as shown in Figure 3.
A vibrating table 3 equipped with a vibration table 1182 is installed so that it can be rotated upward by a hydraulic jack or the like by a required angle with one end as a rotational fulcrum 0, and a dehydration tank 4 with an open top is installed above it.

The dewatering tank 4 is formed in a box shape, and an earth discharge door 5 is attached to the peripheral wall of the vibration table 3 on the side of the rotational fulcrum O, and is rotatable downward with its lower edge as the rotational fulcrum P.

Then, the airtight box 6 is carried into the dehydration tank 4 through the opening J: 111A, and it is penetrated into the dehydration treatment ±S of the high water content soil that is put into the dehydration tank 4. It is supposed to be done.

The airtight box 6 is formed into a box shape with a downward opening at the bottom.
Attached to its top surface is a transport press-in machine 8 that can move vertically and horizontally, such as the flexible arm of a backhoe installed on a fixed base 7 (Fig. 1) or a moving vehicle 7 (Fig. 2) such as a crawler. Moreover, a plurality of strainer pipes 9 are provided inside thereof to project downward from the upper surface.

Each strainer tube 9 is composed of a porous double tube with a sharp tip, and as shown in FIGS. 6 and 7, the porous inner and outer tubes 9a
, 9b is removably loaded with a fine water-permeable material 10 such as a non-woven fabric or fine particles such as sand with a comparatively zero diameter, and its upper end branches off from a flexible vacuum hose 12 of a vacuum pump 11. It is removably fixed to a joint pipe 14 having an on-off valve 13 such as a solenoid valve connected to the water suction branch pipe 12' by means of a screw type or the like.

Note that the strainer tube 9 may not be fixed to the airtight box 6, but may be inserted into the upper surface of the airtight box 6 in an airtight manner so as to be able to rise and fall freely by means of a jack.

Next, a method of dehydrating using the dehydrating apparatus configured as described above will be explained.

First, a required amount of dehydrated soil S, which is highly water-containing soil, is put into the dehydration tank 4 through its upper opening using a crumb backhoe or the like.

Next, the airtight box 6 is placed over the dehydration process ±S in the dehydration tank 4.
The transporting press-fitting machine 8 adjusts the movement up and down, back and forth, right and left, and positions it at a desired position, and then the transporting press-fitting machine 8 moves it downward to penetrate into the dewatering process ±S together with the strainer pipe 9.

In this case, as the airtight box 6 is press-fitted, the air inside the box 6 is expelled to the outside through the strainer pipe 9.

In addition, when the strainer pipe 9 is provided in the airtight box 6 so as to be able to rise and fall freely, after the airtight box 6 is penetrated into the dehydration treatment ±S, the strainer pipe 9 is moved up and down by the lifting jack to remove the dehydrated soil S.
Penetrate inside.

On the other hand, after or before the penetration of the airtight box 6 and the strainer pipe 9, the dehydration tank 4 is vibrated (including rocking) by the vibration table 3.
This forces the water in the dehydrated soil inside to seep out and release it.

Note that as a means for applying vibration to the dewatered soil S, a vibrator 2 may be attached to the upper part of the airtight box 6 to vibrate the airtight box 6.

In this state, the vacuum pump 11 is driven to vacuum the inside of each strainer pipe 9 through the vacuum hose 12 and each water suction branch pipe 12°, and the free water is sucked in while being filtered by the water permeable material IO and discharged to the outside. do.

At this time, since the entire interior of the dehydration tank 4 is made airtight, the internal pressure decreases as the vacuum is drawn by each strainer tube 9, making it easier for water to be sucked into the strainer tubes 9, resulting in extremely efficient dehydration. That will happen.

After dewatering a predetermined portion of the dewatered soil S in the dewatering tank 4 in this way for the required time, the airtight box 6 and strainer pipe 9 are pulled out from the dewatered soil by the transport press-in machine 8, and then removed. The dehydration process ±S is moved to another position, and the airtight box 6 is moved up and down, front and back, left and right by the transport press-fitting machine @8 and adjusted to the desired position, and then lowered by the N transport press-fitting machine 8. Dehydration treatment ±S with strainer pipe 9
Penetrate inside.

Then, the same steps as above are repeated over the entire dehydrated soil S to uniformly dehydrate it.

If necessary, when repeating the dehydration process, only the on-off valve 13 of the water suction branch pipe 12' connected to the strainer pipe 9 corresponding to the position where the dehydration condition is partially bad is opened and the others are closed. It is also possible to carry out dehydration in a concentrated manner.

After dehydrating the dewatered soil S in this way to reduce the moisture content below the standard value, the shaking table 3 is rotated upward together with the dehydration tank 4 to tilt it toward the soil discharge door 5, and at the same time While the dewatering tank 4 is vibrated by the vibration table 3 as necessary, the soil discharge door 5 is opened to automatically discharge the soil to the outside.

When the strainer pipe 9 becomes clogged, fresh water is pumped into it to clean it, and if the strainer pipe 9 becomes severely clogged due to long-term use, the water-permeable material io is replaced.

``Effects of the Invention'' As described above, according to the present invention, an airtight box attached to a conveying press-fitting machine that can be moved vertically and horizontally is placed in highly water-containing soil put into a dehydration tank, with its lower opening facing downward. At the same time, a strainer tube protruding downward into the inside of the airtight box is penetrated, vibration is applied to the dehydration tank to exude moisture, and this moisture is vacuum-sucked by the strainer tube to the outside. The synergistic effect of forcibly exuding moisture through the vibration of the dehydration tank, making the inside of the airtight box airtight, and strengthening the water absorption effect through vacuum suction, efficiently dehydrates the highly hydrated soil and removes water from the airtight box and strainer. - By sequentially changing and moving the penetration position of the pipe, the same dewatering process is closely repeated over the entire dehydrated soil, and it can be economically treated as ordinary residual soil with a uniformly reduced water content.

Furthermore, a soil removal door that can be opened and closed is installed on a part of the peripheral wall of the dewatering tank.
Since this dewatering tank is made rotatable with the soil discharge door facing downward, the dewatered soil can be quickly and automatically discharged from the dewatering tank.

Furthermore, by making the strainer pipe a double perforated pipe with inner and outer holes, and by inserting and removing a fine water-permeable material between the inner and outer perforated pipes, clogging can be reduced, and if clogging occurs, it can be easily removed. The water-permeable material can be easily cleaned from the inside, and the water-permeable material can also be easily replaced.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an example of the dehydration process using the dehydration apparatus of the present invention, FIG. 2 is a side view showing another aspect of the dehydration apparatus of the invention, and FIG. 3 is a perspective view showing the dehydration process using the dehydration apparatus of the invention. 4 is a plan view of the same, FIG. 5 is a vertical sectional view of the airtight box according to the present invention, FIG. 6 is a cross-sectional view of the strainer pipe according to the present invention, and FIG. 7 is a vertical sectional side view. It is a diagram. l...base, 2...vibrator, 3...vibration table, 4...dehydration tank, 5...earth removal door, 6...airtight box, 7...fixing stand. 7'...Moving vehicle, 8...Transportation press-fitting machine. b Strainer pipe, 9a... Porous inner pipe, - Porous outer pipe, lO... Water-permeable material. - Vacuum pump, 12... Vacuum hose 2' - Water suction branch pipe, 13... Open/close valve.・Joint pipe, S... Dehydrated soil. Figure 4

Claims (1)

[Scope of Claims] 1) An airtight box attached to a transportation press-in machine that can be moved vertically and horizontally is inserted into the highly water-containing soil placed in a dehydration tank with its lower opening facing downward, and the airtight A strainer tube protruding downward is penetrated into the inside of the box, vibrates the highly water-containing soil to exude moisture, and this moisture is vacuum-sucked by the strainer tube and discharged to the outside. Dewatering method for highly hydrated soil. 2) a dehydration tank installed so as to be freely vibrated by a vibrator; an airtight box with an open bottom attached to a transportation press-fitting machine that can be moved vertically and horizontally; A dewatering device for highly hydrated soil characterized by comprising a strainer tube that can be vacuum-suctioned by a vacuum pump. 3) Highly hydrated soil according to claim 2, characterized in that a part of the peripheral wall of the dewatering tank is provided with a soil discharge door that can be opened and closed, and the dewatering tank is rotatable with the soil discharge door facing downward. dehydration equipment. 4) Dewatering of highly water-containing soil according to claim 2, characterized in that the strainer tube is a double porous tube with inner and outer holes, and a fine water-permeable material is removably inserted between the inner and outer porous tubes. Device.