JP2004237137A - Meshed bag for capturing heavy metal - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a meshed bag for capturing a heavy metal, by which the harmful heavy metal contained in the soil of a rice field, a riverbed or the like is captured effectively. <P>SOLUTION: This meshed bag for capturing the heavy metal is provided with the meshed bag 3 to be buried in a part of the soil 2 and a bark disrupted body 4 which is packed in the bag 3, has a function of capturing the heavy metals and is obtained by crushing bark. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a mesh bag for capturing harmful heavy metals contained in paddy soil, riverbed soil, and the like.
[0002]
[Prior art]
Paddy soils and riverbed soils can contain harmful heavy metals. According to a national survey last year, 0.4 to 1.0 ppm of cadmium was detected in 33 out of 411 paddy soils, and it is said that 8000 ha of paddy soil is still contaminated. Harvested rice has been heavily damaged, either being disposed of or used for other purposes than food and fertilizer.
[0003]
Conventionally, methods to remove this harmful heavy metal include chelation insolubilization, vitrification of soil, and removal and replacement.However, these methods are enormously expensive, so general farmers and municipalities Is often difficult to implement.
Patent Document 1 below discloses a method of adding tannin-containing tree chips, wood flour, bark, and the like to wastewater containing heavy metals.
[0004]
[Patent Document 1] Japanese Patent Application Laid-Open No. 5-277467
[Problems to be solved by the invention]
However, the method of Patent Document 1 does not solve a specific method for removing harmful heavy metals from paddy soil, for example.
An object of the present invention is to solve the above-mentioned problems, and an object of the present invention is to provide a heavy metal capturing mesh bag capable of effectively capturing harmful heavy metals contained in paddy soil, riverbed soil, and the like.
[0006]
[Means for Solving the Problems]
Therefore, the heavy metal capturing mesh bag of the present invention includes a mesh bag buried in a part of the soil, and a bark crushed body filled in the mesh bag, and the bark crushed body has a heavy metal capturing function. It is characterized by having bark crushed.
[0007]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic view showing one embodiment of a mesh bag for capturing heavy metals according to the present invention. Although the present embodiment is applied to paddy soil, it is also applicable to riverbed soil and the like.
[0008]
In FIG. 1, a part (about 1/3) of the mesh bag 3 is buried in the soil 2 of the paddy field 1. The mesh bag 3 is made of a resin fiber material that is hard to be cut by the double-structured net, prevents the breakage portion from being enlarged by Russell knitting, and maintains sufficient weather resistance and chemical resistance. The size of the mesh bag 3 varies depending on the method of use. For paddy fields, the workability is about 20 liters, and for rivers, the capacity is 1 to ³ m3. It is provided.
[0009]
The mesh bag 3 is filled with a bark crushed body 4 obtained by crushing bark having a heavy metal capturing function. As the bark having a heavy metal trapping function, molysima acacia, ezo willow and the like having a high tannin content are optimal, but hiba, cedar, hinoki and larch are also effective. The bark crushed body 4 has a larger surface area and a higher heavy metal trapping effect when crushed to the minimum size without leaking from the mesh of the mesh bag 3. If the bark crushed body 4 is mixed with a clay mineral, zeolite, activated carbon, charcoal or the like as a powder, the effect is enhanced. Since tannin is water-soluble, it has the effect of preventing this outflow.
[0010]
When the mesh bag 3 is buried about 1/3 in the soil 2 of the paddy field 1 and left as it is, when the moisture in the soil 2 rises through the bark crushing body 4 in the mesh bag 3, heavy metal is crushed by the bark crushing body. 4 and adsorbed. The water in the upper part of the mesh bag 3 rises to the top by capillary action and is dried in this gas phase, so that moisture in the soil gradually passes through the bark crushed body 4 for a long period of time to remove heavy metals in the soil. it can.
[0011]
The mesh bag 3 of the present invention was placed in an aqueous solution adjusted to 1 mg / liter of cadmium, stirred, and allowed to stand for one week. After that, the cadmium concentration was reduced to 0.1 mg / liter, and a trapping effect was confirmed.
[0012]
【The invention's effect】
As is apparent from the above description, according to the present invention, a mesh bag buried in a part of soil, and a bark crushed body filled in the mesh bag, wherein the bark crushed body is a heavy metal Since the bark having the capturing function is crushed, harmful heavy metals contained in paddy soil, river bottom soil, and the like can be effectively captured.
[Brief description of the drawings]
FIG. 1 is a schematic view showing one embodiment of a mesh bag for capturing heavy metals according to the present invention.
[Explanation of symbols]
1: paddy field, 2: soil, 3: mesh bag, 4: bark crushed body

Claims (1)

A mesh bag buried in a part of the soil, and a bark crushed material filled in the mesh bag, wherein the bark crushed material is obtained by crushing bark having a heavy metal capturing function. Mesh bag for capturing heavy metals.

Images