JPS5813817A - Dewatering work for soft ground - Google Patents

Abstract

PURPOSE:To carry out the dewatering of sludge layer, the removal of odors, the lowering of COD value and the regulation of a pH of leached water by forming a granular dewatering layer consisting primarily of activated carbon and an inorganic material in the surface layer of the sludge layer. CONSTITUTION:Sludge is charged into weirs 1 and 2 to form a sludge layer A, and a granular dewatering layer B composed of activated carbon and an inorganic material as main components is provided in the surface layer of the sludge layer A, thereby performing the dewatering of the sludge layer A, the removal of odors, the lowering of COD value and the adjustment of the pH of leached water. The dewatering layer B used is made up of a combination of inorganic materials consisting of such industrial wastes as coal bottom ash, flyash, natural and synthetic zeolites, etc.

Description

[Detailed description of the invention] The present invention relates to a dewatering method for soft ground.

Conventionally, when constructing reclaimed seawalls, embankments, etc., sludge and the like are used for reclamation, and the soft ground soiled by the sludge has been dewatered by various methods. Examples of these conventional construction methods include, for example, the Jizokari construction method, in which a sand layer is placed on top of the sludge layer, and on top of that a layer of cloth layered with hydraulic material;
A sheet, a net construction method, or the above-mentioned sea F in which a sheet net layer, bedding sand Pt1, and a surface coating layer are sequentially provided on a sludge layer.
In the Netshi construction method, a partial dewatering layer is provided in the sludge layer, and partial dewatering, sheeting, net seven method, etc. are included.

However, although these conventional methods can clarify hair water, they are unable to remove odors derived from sludge, adjust the pH of leachate, and reduce O, O, and D values. .

The present inventor has conducted various researches to solve the drawbacks of these conventional construction methods, and has finally completed the present invention.

That is, the present invention is a dewatering method for soft ground in which water in the sludge layer is drained by forming a granular dehydrating agent layer (hereinafter referred to as a dehydrating agent layer) mainly consisting of the surface gK of the sludge layer, activated carbon, and inorganic materials.

The dehydrating agent layer used in the dehydrating agent layer of the method of the present invention consists of various industrial wastes such as activated carbon, blast furnace slag (granulated), red mud, cement F degraded latsis, coal bottom ash, fly ash, and naturally synthesized zeolite. It is made by combining inorganic materials. These materials are uniformly mixed and granulated. Further, these dehydrating agents can be used by adding an acid or alkaline substance to adjust the dehydrating agent to be acidic or alkaline, if desired.

Next, the present invention will be layered with reference to the drawings.
It is a sectional view when a dehydrating agent layer (B) is provided on the surface layer of @comb. As shown in FIG. As time passes, the dehydrating agent layer (or the sludge layer) collects water in the gradient and discharges it to the surface layer. This is preferable as a water-permeable layer [=XA state. Although not shown in the drawing, a water-permeable material layer is provided on the upper and lower surfaces of the dehydrating agent layer (B1). It can also be formed to be sandwiched.

FIG. 2 is a sectional view showing another state of the present invention.

That is, the dewatering effect can be further enhanced by providing a dehydrating agent layer on the surface of the sludge layer (N) and further providing a bedding layer on the surface.

As another example, as shown in Figure 3, the drainage effect can be further enhanced by providing a dehydrating agent layer in the vertical direction of the slope as well as a sludge layer (in the vertical direction of the slope). Sludge layer (dehydrating agent layer (B) provided on the surface of the sludge layer)
By further providing a bedding layer (φ) on the surface layer, the drainage effect can be further enhanced by its own weight.
The dehydrating agent layer according to the method of the present invention may be formed by forming layers using individual dehydrating agents, but in other cases, a damp water-permeable material is prepared in the shape shown in Figures 4 to 6, and Fill the inside with a dehydrating agent and use these to form the dehydrating agent layer (B).
Examples of the water-permeable material include cloth, cloth knitted with synthetic resin strings, and Fabric 7 Ohm (trade name, manufactured by Asahi Kasei Industries, Ltd.).

Even more preferable results can be obtained if the dehydrated material used in the present invention is mixed into the bedding layer (q).

The dewatering method of the present invention not only improves the drainage efficiency of water in the sludge layer, but also removes odors, which were considered impossible with conventional methods, reduces O, O, and D values, and improves the PH1ii of effluent water.
! It is possible to perform i-alignment, etc.

[Brief explanation of drawings]

Figures 1 to 3 are cross-sectional views of an embankment to illustrate an example of the construction method of the present invention, and Figures 4 to 6 are perspective views of storage bodies made of water-permeable material for filling with a dehydrating agent. 1.2----Ichichiku Embankment People----Video Mud Layer B----Dynamic surface agent layer o----1 Layer Sand
Layer patent applicant Nippon Solid Co., Ltd.

Claims (1)

[Claims] A dewatering method for soft ground characterized by forming a granular dehydrating agent layer mainly composed of activated carbon and inorganic materials on the surface of a sludge layer to drain leachate.