JP6208441B2 - Excavated soil discharging device containing harmful gas in shield method - Google Patents

Description

  TECHNICAL FIELD The present invention relates to a drilling soil discharge device including harmful gas in a shield method, for example, a drilling soil discharge device capable of safely discharging methane gas contained in the ground to the outside of a ground in a mud pressure shield method. It is about.

  Conventionally, in tunnel excavation work using the shield method, when toxic gas such as methane gas is included in the excavated soil, it is necessary to take measures to discharge the toxic gas leaked into the mine to the outside of the mine. is there. For example, when there is a possibility of generating methane gas, it is necessary to install explosion-proof equipment, install ventilation equipment in the mine, dilute to a safe concentration by ventilation, or discharge methane gas itself outside the mine.

  Specifically, an air curtain or the like is set as a predetermined section at the rear of the shield machine as an explosion-proof area, and is partitioned from a non-explosion-proof area. In addition, electric equipment for the shield machine body, electric hoist for segment transportation, underground lighting equipment, etc. will be explosion proof. Further, an automatic gas detection alarm device is provided to generate an alarm when methane gas having a predetermined concentration or more is detected. In this case, an automatic power shut-off device that automatically shuts off the power in the mine may be provided.

  Conventionally, in tunnel excavation work using a shield method, various techniques for discharging harmful gases such as methane gas to the outside of the mine have been disclosed (for example, see Patent Document 1). The technology described in Patent Document 1 is provided with a chamber for collecting harmful gas at the exit of a soil discharge conveyor that discharges the earth and sand excavated by a face in the shield tunnel to the tail part of the shield. An exhaust line is formed to communicate with a harmful gas processing plant installed outside the mine. And it has the structure which interposed the pump for exhausting the harmful gas collected by the chamber to a processing plant with respect to an exhaust line.

JP 7-102899 A

  However, in order to make the underground mine explosion-proof, various measures are required, and there is a problem that the equipment cost increases. Moreover, the technique described in Patent Document 1 collects methane gas by closing the chamber when detecting methane gas having a predetermined concentration or more, but until the chamber is closed after the gas detection device detects the gas. There was a time lag, and it was difficult to say that methane gas could be collected completely.

  The present invention has been proposed in view of the above-described circumstances, and it is possible to safely and surely discharge harmful gases discharged from excavation without providing special handling equipment that increases equipment costs. An object of the present invention is to provide an excavating soil discharge device containing harmful gas in the shield method.

In order to achieve the above-described object, the excavated soil discharge device containing harmful gas in the shield method of the present invention has the following features. That is, the excavated soil discharge device containing harmful gas in the shield method of the present invention is a device for discharging excavated soil containing harmful gas excavated by the shield machine to the outside of the mine, and discharges excavated soil from the face. The excavated soil pressure feed pump connected to the rear end of the screw conveyor so that the excavated soil discharge path is in a sealed state, and the excavated soil pressure fed pump connected to the excavated soil pressure fed pump in a sealed state to convey the excavated soil to the outside of the mine. With a pipe .

  In addition, in the conventional mud pressure shield method, the method of carrying out excavated soil using a pressure pump may be adopted. However, in the conventional mud pressure shield method, when excavated soil is transported using a pressure pump, the excavated soil discharged from the screw conveyor is temporarily transferred to the hopper of the pressure pump using a belt conveyor or pipe. Store. And the excavation soil stored by the hopper is conveyed outside a mine by a pumping pump and a pumping pipe. In addition, when the transport distance is long, the excavated soil is relayed and transported by a plurality of pressure pumps, and in this case, the excavated soil is temporarily stored in the hopper of each pressure pump. Become.

  Therefore, in the conventional mud pressure shield method, the excavated soil before being fed into the pump is exposed in the mine. Therefore, if the excavated soil contains harmful gas, this toxic gas will enter the mine. It will leak out. In this regard, the excavated soil discharge device containing harmful gas in the shield method of the present invention communicates the screw conveyor, excavated soil pressure feed pump, and excavated soil pressure feed pipe in a sealed state. It has a completely different configuration from the method of carrying out excavated soil using a pumping pump and a pumping pipe for which no countermeasure has been taken.

A sealing material is interposed between the rear end portion of the tail portion of the shield machine, which is an entry path for harmful gases, between the rear end portion of the shield jack and the segment, and between the adjacent segments. It is.

  In addition to the above-described configuration, the excavating soil discharging device containing harmful gas in the shield method of the present invention is a crushing device for crushing gravel or the like between the excavating soil pressure pump and the rear end of the screw conveyor. Can be provided such that the excavated soil discharge path is in a sealed state.

  In addition to the above-described configuration, the excavated soil discharge device including harmful gas in the shield method of the present invention is included in the excavated soil that has been transported to the rear end portion of the excavated soil pumping pipe led out of the mine. It is possible to provide a gas separation device for separating and storing harmful gases.

  According to the excavated soil discharge device containing harmful gas in the shield method of the present invention, since the excavated soil carry-out route is sealed, the excavated soil contains harmful gases such as methane gas. There is no risk of gas leaking into the mine. Therefore, it is not necessary to provide special equipment such as explosion-proof equipment that increases the equipment cost, and it is possible to safely and surely discharge the harmful gas discharged during excavation to the outside of the mine.

Also, excavated soil is discharged by interposing a sealing material between the rear end of the tail part of the shield machine, which is an entry path for harmful gases, between the rear end of the shield jack and the segment, and between adjacent segments. It becomes possible to improve the sealing property of the path.

  In addition, when a crushing device for crushing gravel etc. is provided between the excavated earth pressure pump and the rear end of the screw conveyor, the excavated earth contains gravel etc. exceeding the inner diameter of the excavated earth pressure feed pipe. Even in such a case, the excavated soil pressure-feed pipe is not blocked by gravel or the like, and the excavated soil can be reliably conveyed to the outside of the mine.

  In addition, when a gas separation device for separating and storing harmful gases contained in the excavated soil that has been transported is provided at the rear end of the excavated soil pressure-feeding pipe led out of the mine, Are not released into the atmosphere. Therefore, combustible gas such as methane gas can be collected and effectively used. Moreover, about poisonous gas, such as hydrogen sulfide, by performing an appropriate process, it becomes possible to prevent air pollution and to maintain a favorable natural environment.

The schematic block diagram of the shield machine used with the excavation soil discharge apparatus containing the noxious gas in the shield construction method of this invention. BRIEF DESCRIPTION OF THE DRAWINGS The whole schematic block diagram of the excavation soil discharge apparatus containing the noxious gas in the shield construction method of this invention. The schematic diagram which shows the tail part of a shield machine.

  Hereinafter, with reference to the drawings, an embodiment of an excavated soil discharge device including a harmful gas in the shield method of the present invention (hereinafter abbreviated as an excavated soil discharge device) will be described. 1 to 3 illustrate an excavated soil discharge device according to an embodiment of the present invention. FIG. 1 is a schematic configuration diagram of a shield machine, FIG. 2 is an overall schematic configuration diagram of an excavated soil discharge device, and FIG. It is a schematic diagram which shows the tail part of a machine.

<Applicable objects for excavating soil discharge device>
In the following embodiment, methane gas (CH ₄ ) will be described as an example. However, harmful gases to be emitted in the present invention are petroleum-based gas containing ethane and butane, and coal-based methane as a main component. It includes flammable gases such as gas and water-soluble natural gas, and gases harmful to the human body such as hydrogen sulfide, carbon dioxide, and carbon monoxide.

  Moreover, in the embodiment shown below, the case where the present invention is applied to the mud pressure shield method will be described as an example. However, as long as the method can transport excavated soil in a sealed state, other shield methods may be used. Can be applied.

<Outline of excavated soil discharge device>
The excavated soil discharging apparatus according to the embodiment of the present invention is a technique that is preferably applied particularly to the mud pressure shield method. As shown in FIG. 1, the shield machine 10 used in the mud pressure shield method forms a mud clay chamber 13 by providing a partition wall 12 at the rear part of the cutter wing 11. Then, the mud material is poured into the excavated soil excavated by the cutter and mixed with a kneading device (for example, the mixing blade 14) to convert the excavated soil into an impermeable and plastic fluid mud. The mud chamber 13 and the screw conveyor 15 are filled. While maintaining this state, the shield jack 16 is pressed against the end face of the segment 20 and the thrust generates mud pressure in the mud in the mud mud chamber 13 to balance the amount of excavation and the amount of soil discharged by the shield machine 10. Excavate while planning.

  The soils to which the mud pressure shield construction method is applied are alluvial clay soil, diluvial clay soil, sandy soil, etc., and flammable gas such as methane gas may be contained in the ground to be excavated. The excavated soil discharge device according to the embodiment of the present invention is used when excavating the ground containing such a combustible gas, and performs the construction safely without leaking the combustible gas into the mine. Can do.

<Configuration of excavated soil discharge device>
As shown in FIGS. 1 and 2, the excavated soil discharging apparatus according to the embodiment of the present invention includes an excavated soil pumping pump 30 and an excavated soil pumped pipe 40 as main components, and includes a screw conveyor 15 and an excavated soil. A crushing device 50 can be provided between the pumping pump 30 and the pumping pump 30. Furthermore, as shown in FIG. 2, a gas separation device 60 can be provided at the rear end of the excavated soil pressure-feeding pipe 40.

<Drilling earth pressure pump>
The excavated soil pumping pump 30 is connected to the rear end of the screw conveyor 15 so that the excavated soil discharge path is hermetically sealed. This excavated soil pressure pump 30 can be manufactured by adding some modifications to the conventionally used mud pressure pump. In addition, when the conveyance path | route (excavated soil pressure feeding pipe 40) is long distance, you may install the excavated earth pressure feeding pump 30 for a relay in an appropriate location. Also in this case, the excavated soil pumping pump 30 is connected so that the excavated soil discharge path is in a sealed state.

  Sealed state means that no harmful gas leaks from the excavated soil discharge path by interposing gaskets or O-rings (oring) at the connecting parts of each component device or by applying a sealing material or the like. Say. Gaskets, O-rings, and sealing materials must be made of materials that are not eroded by harmful gases contained in excavated soil. Depending on the type of harmful gases, for example, those containing fluorine resin or silicon Can be used (the same applies to the following members).

<Drilling earth pressure feeding pipe>
The excavated soil pressure feed pipe 40 is connected to the excavated soil pressure feed pump 30 in a sealed state, and is a pipe for conveying the excavated soil to the outside of the mine. This excavated soil pressure-feeding pipe 40 can be manufactured by slightly modifying the excavated earth pressure-feeding pipe 40 that has been widely used conventionally. Note that the diameter, material, length, and the like of the excavated soil pressure-feeding pipe 40 can be appropriately changed according to the situation at the site, such as the soil quality at the construction site, the shape of the tunnel, and the like.

<Crushing device>
The crushing device 50 is a device provided between the excavated soil pressure feed pump 30 and the rear end of the screw conveyor 15, and crushes gravel and the like contained in the excavated soil. The crushing device 50 is provided such that the excavated soil discharge path is in a sealed state. The crushing device 50 can be manufactured by slightly modifying a conventionally used crusher. That is, the crushing device 50 of the present embodiment is a device generally called a crusher, and is a device that sandwiches gravel between a pair of ropes or rolls and crushes the gravel with a compressive force or an impact force.

<Gas separator>
The gas separation device 60 is a device provided at the rear end portion of the excavated soil pressure feeding pipe 40, and separates and stores harmful gases contained in the excavated soil that has been conveyed. That is, in the ground portion outside the mine, the gas separation device 60 is connected in a sealed state to the rear end portion of the excavated soil pressure feeding pipe 40 to separate harmful gases contained in the excavated soil.

  The separated harmful gas is stored in the storage tank 70 and appropriately discharged. If the harmful gas is a flammable gas such as methane gas, it can be used as fuel by filling a gas cylinder or transporting it by a gas pipe. Further, if the toxic gas is a toxic gas such as sulfurous acid gas or nitrous acid gas, it may be diffused into the atmosphere after removing toxic components using a desulfurization device or a denitration device so as to satisfy environmental standards.

  The excavated soil after separating the harmful gas may be discarded as industrial waste, but can also be reused as landfill.

  In addition, when the harmful gas contained in the excavated soil is very small and is not harmful to the human body, the gas separation device 60 can be omitted. In this case as well, it is necessary to always monitor the gas concentration and take appropriate measures immediately when it becomes a situation where a harmful gas should be treated.

<Sealing material>
Moreover, in the excavation soil discharging apparatus containing noxious gas of the present invention, as shown in FIG. As the sealing material 80, for example, a silicon sealant can be used. By applying the sealing material 80 to the rear end portion of the tail portion of the shield machine 10, the risk of leakage of harmful gas contained in the soil from between the tail portion of the shield machine 10 and the segment 20 is reduced.

  Furthermore, it is preferable that a sealing material 80 is interposed between the rear end portion of the shield jack 16 and the segment 20 or between adjacent segments 20 so as not to generate a gap through which toxic gas leaks.

DESCRIPTION OF SYMBOLS 10 Shield machine 11 Cutter wing 12 Bulkhead 13 Mud clay chamber 14 Mixing blade 15 Screw conveyor 16 Shield jack 17 Tail seal 20 Segment 30 Excavating soil pumping pump 40 Excavating soil pumping pipe 50 Crushing device 60 Gas separation device 70 Storage tank 80 Sealing material

Claims (3)

A device for discharging excavated soil containing harmful gas excavated by a shield machine to the outside of the mine,
Excavation soil pressure feed pump connected to the rear end of the screw conveyor for discharging the excavation soil from the face so that the excavation soil discharge path is in a sealed state,
A drilling earth pressure feeding pipe connected to the excavation earth pressure feeding pump in a sealed state and transporting the drilling earth to the outside of the mine,
In a shield method characterized by interposing a sealing material between the rear end of the tail part of the shield machine, which is an entry path for harmful gases, between the rear end of the shield jack and the segment, and between adjacent segments . Excavated soil discharge device containing harmful gases. Between the rear end of the screw conveyor and the excavated soil pressure pump, according to claim 1, a crushing device for crushing the gravel or the like, excavated soil discharge path is characterized by providing such a sealed state Excavation soil discharging device containing harmful gas in the shield method described in 1. The gas separation device for separating and storing the harmful gas contained in the excavated soil that has been conveyed is provided at the rear end of the excavated soil pressure-feeding pipe led out of the mine. An excavated soil discharge device containing harmful gas in the shield method according to 1 or 2 .

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