JP3106588U - Soil gas collecting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reliably cut off the ground and the ground surface when collecting gas and volatile components existing in the ground and improving workability. Furthermore, gas that volatilizes from the ground surface to the atmosphere can be reliably collected.
SOLUTION: A soil gas collecting device 10 includes a dome-shaped cover 12 placed on the ground surface, a gas flow part 14 provided so as to penetrate the cover, and a handle 16 provided on the outer surface of the cover. It has. The gas circulation part 14 has a structure in which an outer tube joint 20 arranged in a vertical direction and an inner tube joint 22 arranged in a horizontal direction are connected to and communicate with a manifold 24, and earth and sand are formed below the inner tube joint. A shielding member 26 for preventing intrusion is installed.
[Selection] Figure 1

Description

  In the present invention, when collecting gas and volatile components existing in the ground, or gas that volatilizes from the ground surface into the atmosphere (these are collectively referred to as soil gas), it is placed on the ground surface to collect the atmosphere on the ground. It is related with the dome-shaped soil gas collection instrument used in order to prevent mixing with. This soil gas collecting device is useful for environmental investigations such as soil contamination.

  In recent years, with the closure of factories and gas stations, groundwater contamination and soil contamination due to organochlorine compounds have been discovered in various places, which has become a major social problem. Therefore, it is necessary to accurately measure the distribution state, components, amount, and the like of soil gas (gas and volatile components existing in the ground or gas that volatilizes from the ground surface to the atmosphere).

  Conventionally, in order to measure the gas and volatile components that exist in the ground, a hole is made by driving a steel rod into the ground, a tube is inserted into the hole, and the gas in the ground is sucked through the tube. However, the measurement method is common. In this case, it is necessary to prevent the ground air from being mixed in, and a sealing material is packed between the tube and the hole wall at the ground surface, thereby blocking the ground and the ground surface. However, filling the sealing material is cumbersome and inefficient. Also, if the seal is incomplete, gas will escape from between the tube and the hole wall, so the amount of gas sucked through the tube will be reduced or eliminated, and it will be erroneously determined that there is no generation of soil gas. There is also a risk.

  Recently, in place of filling with a sealing material, a technique has been proposed in which the surface port is sealed with a flat lid (see, for example, Patent Document 1). Although this technique is simplified in terms of work, it is impossible to reliably block the ground and the ground surface simply by placing a flat lid on the ground surface.

In the case of collecting gas that volatilizes into the atmosphere from the ground surface, conventionally, a method has been used in which gas is once collected in a bag for storing the gas and the gas stored in the bag is analyzed. However, there is a possibility that the gas cannot be collected accurately by the method of storing the gas in the bag.
JP 2003-35633 A

  The problem to be solved by the present invention is that, in the prior art, when collecting gas and volatile components existing in the ground, it is not sufficient to ensure that the ground and the ground surface are shut off, and workability is improved. However, it is not possible to reliably collect gas that volatilizes from the ground surface into the atmosphere.

  The present invention comprises a dome-shaped cover placed on the ground surface, a gas flow part provided so as to penetrate the cover, and a handle attached to the outer surface of the cover, The outer tube joint arranged in the vertical direction and the inner tube joint arranged in the horizontal direction are connected to the manifold to communicate with each other, and a shielding member is installed below the inner tube joint to prevent intrusion of earth and sand. It is a soil gas collecting device.

  Here, the dome-shaped cover is an integrally formed product composed of an annular side surface portion that rises vertically, a horizontal disk portion, and a peripheral curved surface portion that smoothly connects them, and a manifold in which the outer tube joint and the inner tube joint are connected. Is preferably hermetically attached to the lower surface of the horizontal disk portion.

  The soil gas collecting device of the present invention covers the dome-shaped cover on the ground surface, so that the lower edge slightly bites into the ground surface, so that the interior of the cover can be surely shielded from the atmosphere on the ground. Accordingly, it is not necessary to fill a sealing material between the tube and the hole wall at the ground surface, so that the workability is good and the shielding property to the atmosphere is very good. Even when a volatile component is collected from the ground surface without inserting a tube into the ground, workability is good because it is only necessary to cover the ground surface with a dome-shaped cover. Both work forms can be handled by the same soil gas collecting device, and there is no need to prepare a sealing material or a bag for storing gas. The soil gas collecting device of the present invention has a very simple structure, can be easily manufactured at low cost, and can be used easily.

  An example of a soil gas collecting device according to the present invention is shown in FIG. Here, A represents a plane and B represents a longitudinal section. The soil gas collecting device 10 includes a dome-shaped cover 12 placed on the ground surface, a gas flow part 14 provided so as to penetrate the cover 12, and a handle 16 attached to the outer surface of the cover 12. It has. The gas flow part 14 has a structure in which an outer tube joint 20 arranged in a vertical direction and an inner tube joint 22 arranged in a horizontal direction are connected to a manifold 24 to communicate with each other. In addition, a shielding member 26 is installed below the inner tube joint 22 in order to prevent the earth and sand on the surface from entering the inner tube joint 22.

  The dome-shaped cover 12 is an integrally molded product including an annular side surface portion 12a that rises vertically, a horizontal disk portion 12b, and a peripheral curved surface portion 12c that smoothly connects them. The shape is easy to handle, for example, with a thickness of 1 mm, a diameter of 350 mm, and a height of about 40 mm. Here, it is manufactured by drawing a stainless steel plate (the peripheral curved surface portion 12c is a curved surface of R30). A manifold 24 connected to a surface where the outer tube joint 20 and the inner tube joint 22 are orthogonal to each other is airtightly attached to the lower surface of the horizontal disk portion 12b. Further, the inverted U-shaped handle 16 is also airtightly attached to the horizontal disc portion 12b. For example, a sealing agent is provided at the attachment portion to completely block the inside and outside of the dome-shaped cover 12.

  The manifold 24 and the outer tube joint 20 and the inner tube joint 22 connected to the manifold 24 are made of, for example, brass. The outer tube joint 20 and the inner tube joint 22 are one L-shaped hole formed in the manifold 24. Are connected. Here, the shielding member 26 is a flat plate made of metal (for example, stainless steel) and is provided so as to shield between the inner tube joint 22 and the ground surface.

  An example of the measurement state is shown in FIG. This is an example of collecting and measuring gas and volatile components present in the ground. A hole 32 is formed by driving a steel rod or the like to a predetermined depth (for example, about 1 m) in the ground 30 to be measured, and the underground tube 34 is inserted into the hole 32. The upper end of the underground tube is connected to the inner tube joint 22. A dome-shaped cover 12 is installed on the ground surface so as to cover the hole, and is pushed in a little. Thereby, the lower edge of the annular side surface 12a slightly bites into the ground surface, and the inside and outside of the dome-shaped cover 12 are almost completely blocked. The ground tube 36 is connected to the outer tube joint 20 and sucked by a pump or the like (not shown). As a result, the gas and volatile components existing in the ground can be reliably collected through the tubes 34 and 36 on the ground side and the ground side. Since the gas that travels through the hole wall without passing through the underground tube fills the inside of the dome-shaped cover 12 and does not diffuse into the atmosphere, it eventually passes through the tube 34 on the underground side, It is sucked and collected through the manifold 24 and the tube 36 on the ground side.

  Another example of the measurement state is shown in FIG. This is an example of collecting and measuring components that volatilize from the ground surface. The inner tube joint 22 is placed in a state where the tube is not connected as it is, and the dome-shaped cover 12 is placed on the ground surface 38 to be measured and is pushed in somewhat. Thereby, the lower edge of the annular side surface 12a slightly bites into the ground surface, and the inside and outside of the dome-shaped cover 12 are almost completely blocked. The ground tube 36 is connected to the outer tube joint 20 and sucked by a pump or the like (not shown). As a result, the gas volatilized from the ground surface fills the dome-shaped cover 12 and passes through the inner tube joint 22 and can be reliably collected through the manifold 24 and the tube 36 on the ground side.

  As described above, the soil gas collection device according to the present invention reliably collects gas and volatile components existing in the ground of the collection site without diffusing the gas that volatilizes from the ground surface to the atmosphere into the air. can do.

Explanatory drawing of the soil gas collection instrument which concerns on this invention. Explanatory drawing which shows an example of the use state. Explanatory drawing which shows the other example of the use condition.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Soil gas collection instrument 12 Domed cover 14 Gas distribution part 16 Handle 20 Outer tube joint 22 Inner tube joint 24 Manifold

Claims (2)

  A dome-shaped cover placed on the ground surface, a gas flow part provided so as to penetrate the cover, and a handle attached to the outer surface of the cover; The outer tube joint arranged and the inner tube joint arranged in the horizontal direction are connected to the manifold so as to communicate with each other, and a shielding member is installed below the inner tube joint to prevent intrusion of earth and sand. Gas collecting instrument. The dome-shaped cover is an integrally formed product comprising an annular side surface portion that rises vertically, a horizontal disk portion, and a peripheral curved surface portion that smoothly connects them, and the manifold to which the outer tube joint and the inner tube joint are connected is The soil gas collecting device according to claim 1, wherein the soil gas collecting device is airtightly attached to a lower surface of the horizontal disk portion.

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