JPH05112965A - Additives feeder to sand and soil pumping pipe - Google Patents

Abstract

PURPOSE:To feed additives at a certain rate in sand and soil conveyed with pressure while repeating formation of sand and soil plug and breaking thereof in a pipe. CONSTITUTION:A spiral chamber 1 is provided in which a submerged sand pump 2 composed of a centrifugal impeller 5 is installed on a pipe way 3 with pressurized mixed air with sand and soil S. A measuring instrument 9 for feeding additives T is jointed through a check valve 7 to the suction side of the submerged sand pump 2. And the measuring instrument 9 is on-off-controlled in accordance with the variation of detected figure of a flow speed meter 13 inside the pipe way 3, equipped apart from the spiral chamber 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an additive supply to a sediment feeding pipe for supplying an additive such as a solidifying agent for soil improvement at a constant ratio to the sediment to be mixed and pressure-compressed by using compressed air. It relates to the device.

[0002]

2. Description of the Related Art Conventionally, when an additive such as a solidifying agent for improving the sediment is supplied into the sediment that has been sending mixed air by using compressed air, a check valve is attached to the sediment sending pipe. The check valve and the additive storage tank are connected by an injection pipe, and a certain amount of the additive stored in the tank is injected by compressed air having a pressure higher than the pressure in the pressure feeding pipe.

However, when the cohesive soil having a high water content ratio, for example, the soft mud-like earth and sand sent from a high-concentration dredger is sent under mixed pressure, compressed air indicated by an arrow A is applied to the earth and sand S in the pipeline 3 shown in FIG. When supplied, the earth and sand S will flow to the bottom of the pipeline 3 in FIG.
From the state where the compressed air A flows over the upper portion of the pipeline 3, the upper portion of the deposited soil S swells as shown in FIG. Close the inside,
It becomes a plugged state, and as a result, the earth and sand S is pumped by the compressed air A in the pipe line 3 and returns to the state close to that in FIG. 5 again, and the phenomenon shown in FIG. 6 and FIG. As shown in FIG. 8, since the earth and sand S proceed in the pipe 3 while repeatedly forming and collapsing plugs in the pipe 3, there are a portion to which only air is sent and a portion to which the earth and sand S are sent. Will pass through alternately.

Moreover, since the plug length L of the earth and sand S is not constant, when the additive is supplied to the earth and sand S that is pressure-fed while repeatedly forming and disintegrating the earth and sand plug in this way, Since the length L of the plug varies, there is a problem that the additive cannot be supplied into the earth and sand S at a predetermined ratio in the conventional additive supply system that supplies a fixed amount of the additive.

[0005]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art, and a constant amount of earth and sand is sent to the inside of a pipeline by repeatedly forming and collapsing earth and sand plugs. It is an object of the present invention to provide an additive supply device to a sand-and-sand pressurizing pipe that can supply the additive at a ratio of.

[0006]

Means for Solving the Problems As a means for solving the above-mentioned problems, an additive supply device for a sediment feeding pipe of the present invention has a centrifugal blade in the middle of a pipe line for feeding the sediment by compressed air. A swirl chamber provided with a submersible sand pump consisting of a car is provided, and a meter for additive supply is connected to the suction side of the submersible sand pump via a check valve, and at a predetermined distance from the swirl chamber. It is configured by appropriately operating and stopping the measuring instrument according to the change in the detected value of the velocity meter or flow meter provided in the pipeline, and detecting that the earth and sand plug has passed by the velocity meter or flow meter, By starting or stopping the supply of the additive from the meter, the additive can be supplied at a constant ratio to the soil to be pumped.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic side view showing a cross section of an essential part of an additive supply device for a soil and sand pressure feeding pipe in one embodiment. Figure 1
2 is a plan sectional view taken along line AA ′ of FIG.
It is a front sectional view of the B'direction. First, in FIG. 2, a swirl chamber 1 as shown in FIG. 3 is provided in the middle of a pipe line 3 for feeding mixed fluid S of soft mud as shown in FIG.
The submersible sand pump 2 composed of the centrifugal impeller 5 and its drive motor 6 is provided inside the submersible sand pump 2 and
As shown in FIG. 1, a hopper 8 and a measuring instrument 9 for feeding the additive T for soil improvement are provided on the suction side of
Is connected, and the motor of this measuring instrument 9 is indicated by 10.

A silo 11 for supplying the additive T is provided on the measuring device 9, and a bag filter 12 is provided above the silo 11. Next, the spiral chamber 1 of the conduit 3
A velocity meter 13 or a flow meter is provided in the pipe line 3 which is away from the device by a predetermined distance D. Therefore, as described with reference to FIG. 8, the plug of the earth and sand S, which has been mixed and pressure-fed in the pipe line 3, is detected by a change in the detected value of the velocity meter 13 or the flow meter, and the motor 10 of the measuring instrument 9 is detected.
The detection signal G is sent to.

From the point in the pipe line 3 where the velocity meter 13 or the flow meter is provided to the point where the measuring instrument 9 for supplying the additive is provided,
Measure the time it takes for the earth and sand plug to reach,
After receiving the detection signal G from the velocity meter 13 or the flow meter, the meter 9 is operated after a predetermined time has elapsed, and the additive T is continuously supplied into the hopper 8. Therefore, the supplied additive T
Is due to the centrifugal force of the centrifugal impeller 5 rotating in the direction of arrow R,
It is supplied into the pipe line 3 and is not blown out into the hopper 8 by the centrifugal force of the centrifugal impeller 5.

Next, when the velocity meter 13 or the flow meter detects that the plug of the earth and sand S has passed, the meter 9 is stopped after a lapse of a predetermined time, and the supply of the additive T is stopped. At this time, since nothing is supplied to the centrifugal impeller 5, the compressed air for pressure feeding in the conduit 3 tries to blow out into the hopper 8, but the check valve 7 functions and blows out into the hopper 8. Can be prevented.

That is, the meter 9 is appropriately operated and stopped in accordance with the change in the detected value of the plug of the earth and sand S of the velocity meter 13 or the flow meter provided in the pipe 3, so that the earth and sand S being pumped can be removed. , After supplying the additive T at a constant ratio, the additive T
The mixed mud St supplied with is fed under pressure through the pipe line 3 on the left side of FIG. 1, and the centrifugal impeller 5 is always rotated in the direction of arrow R during this period.

Next, FIG. 4 shows that an additive T such as a solidifying agent is added to the soft mud-like earth S sent from the high-concentration dredger 15 by pressure-mixing inside the pipe 3 by using the apparatus of the present invention. It shows a continuous treatment system that discharges to the landfill 16 and supplies the additive T with the detection signal G from the flow velocity meter 13
It is adjusted by turning on and off the meter 9 of the additive supply apparatus of the present invention shown by 20.

Here, after the additive T is added, the sediment S and the additive T are repeatedly formed and disintegrated as a sediment plug, so that the conduit indicated by P is obtained by plug flow mixing without providing a kneading means. The kneading is carried out in the section No. 3, but if it is necessary to further enhance the kneading effect, the element of the static mixer 19 may be inserted near the discharge port in the pipe line 3. The dredged softened mud S that is put into the landfill 16 by such a system is increased in strength by the additive T such as a solidifying agent, and the landfill can be used early.

[0014]

EFFECT OF THE INVENTION According to the additive supply device for a sediment feeding pipe of the present invention described above, the additive is added at a constant ratio to the sediment being pressure-fed while repeatedly forming and disintegrating the sediment plug. There is an effect that it can be supplied. In addition, if a solidifying agent is added by applying the device of the present invention to a pipeline for sending the dredged sediment to the landfill in mud pressure, the sediment is sent by pressure while repeating formation and collapse of the sediment plug. There is also an advantage that the ground of the landfill can be strengthened without using a kneading device such as a line mixer depending on the soil quality.

[Brief description of drawings]

FIG. 1 is a schematic side view showing a cross section of a main part of a device for supplying an additive to a sediment feeding pipe according to an embodiment of the present invention.

FIG. 2 is a plan sectional view taken along the line AA ′ of FIG.

3 is a front sectional view taken along the line BB ′ of FIG.

FIG. 4 is a diagram of a continuous processing system of an example in which the device of the present invention is used in a mixed pressure air-feeding pipeline for soft mud-like soil from a dredger.

FIG. 5 is an explanatory diagram showing a state in which compressed air is supplied to the earth and sand in the pipeline.

FIG. 6 is an explanatory diagram showing a state where the upper portion of the earth and sand is wavy from the state of FIG.

FIG. 7 is an explanatory diagram showing a state where the inside of the pipe is plugged with earth and sand from the state of FIG. 6;

FIG. 8 is an explanatory diagram showing a state of a plug of earth and sand sent under mixed pressure by repeating the states of FIGS. 5 to 7;

[Explanation of symbols]

1 Vortex chamber 2 Submersible sand pump 3 Pipe line 5 Centrifugal impeller 7 Check valve 9 Metering device 13 Velocity meter 20 Additive supply device S Sediment T Additive

Claims (1)

[Claims] 1. A swirl chamber provided with a submersible sand pump consisting of a centrifugal impeller is provided in the middle of a pipe line for sending mixed sand and atmospheric pressure, and added to the suction side of the submersible sand pump via a check valve. A soil and sand pressure-feeding pipe for connecting and stopping a meter for supplying the agent, and for appropriately operating and stopping the meter according to a change in the detected value of a flow meter or a flow meter provided in a pipe distant from the swirl chamber by a predetermined distance. Additive supply device to.