JPS5846604B2 - Landfill method - Google Patents

Description

[Detailed description of the invention] The present invention relates to a reclamation method using dredging or the like.

Landfill construction has become popular in recent years, but when reclamation is carried out using pump dredging, etc., the sediment contained in the muddy water is insufficiently settled, causing fine-grained soil to spread over a wide area around the spillway, causing fish damage. It caused great damage to shellfish.

As a result of various research conducted on methods to avoid contamination of the surrounding area of a landfill due to dredging, etc., the present invention has completed a landfill method that does not discharge polluted water exceeding predetermined water quality standards outside the planned landfill site. did.

Next, the method of the present invention will be explained with reference to the accompanying drawings.

First, as shown in FIG. 1, the present invention involves building an embankment and surrounding the area scheduled for reclamation with main columns, steel sheet piles, concrete, etc.

Next, one or more drainage pipes 2 are provided near the embankment 1 within the enclosure.

The drain pipe 2 provided within this embankment has its water intake port 3 installed at a position lower than the height of the embankment.

On the other hand, the discharge port 4 of the drain pipe 2 is provided so as to penetrate the embankment part from inside the embankment 1 and protrude to the outside of the embankment 1.

In addition to being cylindrical, the drainage pipe 2 may have a funnel-shaped water intake port 3 as shown in FIG.

Furthermore, a vertical slit 5 or a horizontal slit as shown in FIG. 3 may be provided on the side wall surface near the top of the drain pipe 2.

When such a slit is provided, water is ejected from the slit into the drain pipe 2, so that the water intake port 3 of the drain pipe 2 can also cause turbulent flow or swirling flow in the water flowing into the drain pipe. .

The slits 5 provided in the drain tube 2 may, for example, be arranged so that the width of each slit is increased in sequence, and the length of the slits is also provided so as to be lengthened in the order in which they are arranged, thereby creating turbulence in the water flow in the drain tube 2. can be effectively caused.

Further, as shown in FIG. 4, if a spout 6 is provided in the slit portion in an oblique direction, a swirling flow can be generated in the water flow within the drain pipe 2.

By providing the spout 6 in the slit 5 or the slit portion in this way, it is possible to impart turbulent flow or swirl to the water flowing in from the water intake port 3 of the drain pipe 2.

Therefore, if a chemical such as a polymer flocculant is added from the top of the drainage tube 2, sufficient mixing and agitation will be achieved, and sedimentation and separation of the earth and sand will be promoted when the agent is circulated within the embankment.

Of course, the above objective can be achieved by adjusting the amount of water flowing into the water intake port 3 without providing the slit 5 or the like in the drain pipe 2.

A discharge port 4 of the drain pipe 2 is connected with a discharge pipe I for discharging discharged water outside the embankment surroundings and a circulation device 8 for circulating the discharged water within the embankment again.

This circulation device 8 is provided with a pump 9 for pumping discharged water into the embankment.

Further, as shown in FIG. 3, the circulation device 8 includes a receiving tank 10 provided at the discharge port 4 of the drain pipe 2, so that the discharged water is once received in the receiving tank 10, and then the water is recirculated through the circulation device 8 into the embankment. You can also do it.

In addition, when the polluted water is recirculated into the embankment through the drain pipe 2 and the circulation device 8, a chemical agent such as a polymer flocculant is added to the chemical injection device (not shown) 11 installed at the top of the drain pipe 2. By doing so, when the polluted water is returned to the embankment, sedimentation and separation of the soil contained in the polluted water can be effectively performed.

The muddy water used for reclamation is pumped and dredged, and the mud pipe 1
2 is supplied into the embankment.

According to the method of the present invention, if the water discharged from the drain pipe 2 is below a predetermined water quality standard, it is directly discharged from the drain pipe 2 into the embankment enclosure through the discharge pipe 7.

In addition, if the discharged water exceeds a predetermined water quality standard, it is returned to the embankment through the circulation device 8, and the sediment in the polluted water can be sedimented and separated again, so it will not pollute the water quality around the area scheduled for reclamation. .

Furthermore, when the method of the present invention is used to carry out reclamation, there is an advantage that the reclamation can be carried out almost uniformly over the entire area within the embankment.

Next, in order to explain the present invention more specifically, examples will be given.

Example: Mud water is sent from a mud pipe 12 into an embankment surrounding a planned landfill site.

The inside of the embankment is gradually filled with muddy water, and when the water level reaches the water intake port 3 of the drain pipe 2, the water is discharged through the drain pipe 2.

Sediment in the muddy water is also discharged through the mud pipe 12 and settles within the embankment before reaching the drain pipe 2.

If the water discharged from the drain pipe 2 is below a predetermined water quality standard, the valve of the circulation device 8 is closed, while the discharge port 4 of the drain pipe 2 is closed.
By opening the valve of the discharge pipe 7 provided in the discharge pipe 7, the discharged water is discharged outside the embankment enclosure.

If the quality of the discharged water is higher than a predetermined standard, the water taken from the drainage tube 2 is returned to the embankment through the circulation device 8, and the earth and sand are re-sedimented, and the earth and sand are separated.

In this case, if polluted water containing fine particles such as silt and colloid is to be recirculated, an agent such as a coagulant is added from the top of the drain pipe 2.

The added chemicals are stirred and mixed while passing through the drain pipe 2, dissolved in the polluted water, and returned to the embankment by the circulation device 8, thereby making it possible to settle fine particles of earth and sand.

[Brief explanation of drawings]

In the accompanying drawings, Fig. 1 shows a plan view of the area scheduled for reclamation, Fig. 2 shows a sectional view taken along line A-A' in Fig. 1, Fig. 3 shows a partially enlarged view of the vicinity of the drainage pipe, and Fig. Figure 4 shows an enlarged plan view of the water intake of the drain pipe. 1... Embankment, 2... Drain pipe, 3... Water intake, 4...
...Discharge port, 8...Circulation device, 12...Sludge feeding pipe.

Claims (1)

[Claims] 1. The reclaimed area shall be surrounded by an embankment, and at least one place near the embankment within the enclosure shall have a water intake port for a drain pipe at a position lower than the height of the embankment, and the discharge port of the drain pipe shall protrude outside the embankment enclosure. In the enclosed area of the reclaimed land, where the discharge port is provided with a circulation device, the muddy water is made to flow from the intake port of the drainage pipe, and is discharged from the discharge port through the circulation device into the embankment to remove the sediment in the muddy water. A landfill construction method that does not discharge polluted water outside the embankment enclosure, which is characterized by sedimentation and separation within the embankment enclosure.