JPS62273397A - Method of treating bubble mixed muck - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] 3. Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a method for disposing of air bubble-mixed waste in which air bubbles are retained in excavated soil when excavating a tunnel with a shield promoting machine. .

(Prior art and its problems) Conventionally, air bubbles generated or mixed into the sludge using an air entraining agent or foaming agent made of a nonionic activator such as a polyoxy compound or a sulfone compound have been found to cause fluidity in the sludge. Because it provides water-stopping properties, it is effective in reducing the cutting resistance of the cutter and elevating the shear υ1, and is used in the shield type tunnel excavation method.

However, for example, in construction in a water retention layer, in addition to the above-mentioned foaming agent, a polymeric additive such as a superabsorbent resin or methylcellulose may be added to strengthen the bubbles. It is believed that when such additives are added, the resulting bubbles are in a state where the bubble particles of the additive or foaming agent are dispersed in an aqueous solution, increasing the unit weight and increasing the cohesive force between the bubble particles. However, since the bubbles are strengthened, there is little hope that the excavated waste with accumulated bubbles will be left alone and the bubbles will disappear naturally.

Therefore, in order to eliminate air bubbles, it is possible to use an antifoaming agent such as a surfactant or a higher alcohol.

However, even if such an antifoaming agent is used, it is difficult to defoam the bubbles produced using the additives mentioned above, so the amount of foam consumed increases, and a large amount of waste is discharged by the shield method, so there is a large Q. % antifoam had to be used.

In addition, if a large amount of antifoaming agent is used, the moisture content of the waste after treatment will increase significantly, making handling such as transportation and waste soil cumbersome.

The present invention was created in view of these problems, and its purpose is to provide a method for treating foam-mixed waste in which the use of an antifoaming agent is minimized.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a method for treating foam-mixed waste in which air bubbles are retained in excavated earth and sand when excavating a tunnel with a shield tunneling machine. The method is characterized in that after vibration is applied to the bubble mixture waste discharged from the pressurized area of the shield tunneling machine, an antifoaming agent is sprayed to defoam the bubbles.

(Function) When vibration is applied to the bubble-mixed sludge discharged from the pressurized area of the shield tunneling machine, the air bubbles existing inside the sludge float to the surface of the sludge due to the vibration, making it extremely easy to separate from the sludge. Therefore, if the antifoaming agent is sprayed in this state, even the strengthened bubbles can be intensively and quickly defoamed.

(Embodiments) Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows the first method of treating bubble-mixed waste according to the present invention.
An example is shown, and the treatment method shown in the figure exemplifies the case where the present invention is applied to a so-called bubble shield method.

In the figure, 10 indicates a shield tunneling machine, and tunneling machine 1
0 is the segment 12 installed behind it with excavation.
The propulsion jack 14.14 is equipped with a propulsion jack 14.14 that carries a reaction force, and a cutter head 16 for excavating earth and sand is rotatably supported at the front part of the propulsion jack 14.14. The partition wall 20 defines an earth pressure chamber 18 that takes in the soil (sludge) and maintains the soil at a predetermined pressure state to oppose the face.

The cutter head 16 and the partition wall 20 are each provided with a bubble injection tube 22,22, and the bubble injection tube 22 is provided with a foamer 2.
Bubbles are supplied from 4 through bubble supply pipes 26, respectively.

The foamer 24 has a tank 26 containing foaming agents and additives.
The medicine sent by the pump 28 and the air from the compressor 30 are used to generate dense and reinforced bubbles in the shape of a cream puff.

On the other hand, in the earth pressure chamber 18, a screw conveyor 32 for carrying out waste is provided so as to pass through the partition wall 20, and behind the screw conveyor 32, a screw conveyor 32 is provided to prevent a drop in the pressure inside the earth pressure chamber 18. A rotary valve 34 is provided to discharge the waste to the outside without any problems.

A wt first stand 38 connected to the vibration device 36 is installed below the valve 34, and a nozzle 42 for spraying the antifoaming agent contained in the tank 4o is installed above the vibration table 38. be.

Further, a belt conveyor 44 is installed close to the vibrating table 38 in order to carry out the waste after the defoaming treatment to the outside.

Now, in the shield construction method constructed with the above configuration, as the shield excavator 10 excavates, air bubbles are released toward the face from the air bubble injection pipe 22 arranged in the cutter head 16, and this causes the cutter to excavate. The earth and sand are excavated in a state where the resistance is reduced, and the excavated earth and sand, that is, debris, is taken into the earth pressure chamber 18 together with air bubbles.

Even within the earth pressure v18, excavation scraps are attached to the bulkhead 2o! Bubbles are injected through the 1 injection pipe 22, mixed and stirred by, for example, a stirrer installed in the Tonosho v18, and the sludge is fluidized into a soft mortar-like form.

In this case, for example, if the excavated ground is a water-retaining layer, the mixing ratio of air bubbles may be increased, or a polymer additive may be added to the foaming agent.

In this way, the fluidized air bubble mixture becomes highly compressible and is sent rearward by the screw conveyor 32 without reducing the pressure inside the earth pressure chamber 18, and is transferred from the valve 34 to the normal pressure region. be discharged.

The transported waste is received on a vibration table 38, and first, vibration is applied by a vibration excitation device 36.

The air bubbles retained in the sludge are destroyed by the vibration, their separation from the sludge is promoted, and they float to the surface of the sludge.

In this state, if the antifoaming agent is sprayed intensively from the nozzle 42, even strengthened bubbles can be easily defoamed without using many antifoaming agents.

It should be noted that the antifoaming agent may be sprayed from the nozzle 42 at the same time while applying vibrations after the bubbles have risen to the surface to some extent due to vibrations, or may be stopped once the floated bubbles disappear and sprayed intermittently. stomach.

The waste that has undergone the defoaming process is moved from the vibrating table 38 to the belt conveyor 44 and transported out of the mine.

If the defoaming treatment is performed immediately after the bubble-mixed waste is discharged from the valve 34 into the normal pressure region as described above, subsequent handling such as transportation becomes easier.

FIG. 2 shows another embodiment of the treatment method according to the present invention. In this embodiment, the bubble mixed waste discharged from the valve 34 is stored in a trolley 50, and the trolley 50 is placed on a vibration table 38'. The structure is such that defoaming is carried out by vibration by the vibrating mushroom 36' and spraying of the defoaming agent from the nozzle 42-.

If such a treatment method is adopted, the waste is transported to the ground by pumping, for example, and a large treatment membrane installed on the ground can be used, so that the defoaming treatment can be carried out quickly.

(Effects of the Invention) As explained above in the embodiments, according to the method for treating air bubble mixture waste according to the present invention, vibration is applied in advance to the air bubble mixture waste discharged from the pressurized area of the shield advancing machine. , the bubbles rise to the surface and disappear, or the bubbles tend to disappear intensively, so the antifoaming agent only needs to be sprayed temporarily, and the amount of antifoaming agent used is limited, making it economical. It is true.

[Brief explanation of the drawing]

FIG. 1 is a schematic vertical sectional view showing a first embodiment of the present invention;
FIG. 2 is an explanatory view of main parts showing the second embodiment of the same. 10... Shield excavator 16... Cutter head 18... Earth pressure chamber 20... Interval
Wall 22...Bubble injection pipe

Claims (1)

[Claims] In a method for disposing of air bubble mixed waste in which air bubbles are retained in excavated soil when excavating a tunnel with a shield tunneling machine, after applying vibration to the air bubble mixed waste discharged from a pressurized area of the shield tunneling machine, A method for treating foam-mixed debris, which comprises spraying an antifoaming agent to defoam the foam.