JPH04106213A - Control on mixing ratio of chemical grout - Google Patents

Abstract

PURPOSE:To keep gelling time constant by providing a main agent flow meter and a hardener flow meter, a return path to a main agent storage tank, and a return amount regulator for the supplying path. CONSTITUTION:A three-way valve 11 constituting a return amount regulator is provided, and a return tube 12 to a water glass storage tank 1 is provided. A hardener P is supplied to an injection tube 9 by a multiple type pump 10, measured with time by a hardener flow meter 17, and sent to a controller 24. On the basis of a preset mixing ratio, a target supply amount of main agent W is determined by the controller 24, the valve 11 is controlled in such a way as to make the indicating value of the main agent flow meter 15 a target supply amount, and the supply mount of the main agent W is regulated. The mixing ratio of the agent W and the hardener P can thus be kept to a given one to permit the gelling time of the chemical grout to be maintained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a chemical liquid injection method that maintains a constant mixing ratio of a base agent and a curing agent and strives to stabilize the gel time.

[Conventional technology]

For example, in the chemical injection method using water glass,
Water glass, which is the main ingredient, is mixed with hardening agents such as cement, acid salts, baking soda, sodium bisulfate, sodium chloride, and sulfuric acid, and the chemical solution is injected into the ground. The gelation time can be adjusted by adjusting the mixing ratio of the agents.

When injecting a mixture of a base agent such as water glass and a curing agent, for example, as shown in FIG.
A 1 or 5 shot method is used in which 0 and curing agent 31 are fed independently by pumps 32 and 33 and are merged at the injection pipe 34 section. At this time, since the mixing ratio of the base agent and the curing agent affects the gelation time, it is important to always maintain the mixing ratio at a predetermined mixing ratio even if the injection amount changes.

On the other hand, regarding the injection of chemical solutions, there are a constant pressure injection method and a metered injection method, and the constant pressure injection method is generally used. In the constant pressure injection method, at the beginning of injection, the pump pumping flow rate is reduced, and then the pumping flow rate is gradually increased while monitoring the pressure gauge, and when the injection pressure starts to rise rapidly, the pumping flow rate is decreased. In this method, injection is continued by increasing or decreasing the pumping flow rate to maintain the pressure (limiting pressure) on the verge of a sudden rise.

As mentioned above, when injecting a chemical solution, it is necessary to constantly adjust the pumping flow rate of the injection material in order to maintain the pressure within a constant value. If pumped in an independent route,
In order to maintain the gelation time, it is necessary to keep the mixing ratio constant, and therefore the pumping amount of each route must be adjusted at the same time and at a constant ratio, making adjustment cumbersome, making the mixing ratio unstable, and making work difficult. There were problems such as inefficiency and the inability to make quick adjustments.

In recent years, in view of the above problems, for example,
No. 2 discloses a flow rate ratio control device that facilitates adjustment of the flow rate ratio of two liquids shown in FIG.

The device has an independent piping system (C system) from a tank 40 containing a base agent such as cement milk and a piping system (D system) from a tank 41 containing water glass such as sodium silicate. , are merged at the mixing pipe 45 position and the ground 4
6, a flow rate transmitter 44 is disposed in the middle of the C system, and a flow rate regulator 49 controls a regulating valve 47 provided in the middle of the return pipe based on this flow rate signal. While adjusting the flow rate of the C system, in the D system, receiving the signal from the flow rate transmitter 44 of the C system,
The ratio setter 50 sets the flow rate of the D system, the flow regulator 5I controls the regulating valve 48 provided in the middle of the return pipe of the D system, and the ratio of the flow rate of the C system to the flow rate of the D system is determined. This is a device that keeps the temperature constant.

[Problem to be solved by the invention]

However, in the device disclosed in Japanese Patent Publication No. 52-21802, it is not possible to grasp the original feed amount of the injection agent fed through the D system, and the injection tube is In order to calculate the feed rate to the curing agent side, a double pump is generally used as a chemical injection pump, but this type of pump requires a The feeding ratio accuracy has a feeding amount error of approximately ±5% at the time of product shipment, but in actual use, the error is often greater than that, making it impossible to strictly control the feeding amount.

Furthermore, if a regulating valve is provided for each independent path, the cost will be relatively high, and mutual adjustment will be complicated, resulting in a hunting phenomenon.

If a flow rate adjustment valve is placed in the middle of the return pipe, there are problems such as poor response to flow rate adjustment.

In addition, not limited to the above-mentioned known example, in conventional chemical injections of this type, only the flow rate of the base agent is measured, and the flow rate of the hardener side is not measured, so in reality, the base agent and hardener are mixed. There is no guarantee as to what the ratio will be.

Therefore, the main object of the present invention is to mix injected medicinal solutions that can easily and accurately control the mixing ratio at a predetermined ratio without bothering the operator even if the amount of injected medicinal solution is changed. The object of the present invention is to provide a ratio control method.

[Means to solve the problem]

The problem is that in a chemical injection method in which the base agent and hardener are injected into the surrounding ground from an injection pipe in a 1.5-shot or 2-shot method using an injection pump through mutually independent feeding routes, the base agent and hardener are A flow meter for the base agent and a flow meter for the hardener are respectively disposed between the injection pump outlet and the injection pipe in the hardening agent supply route, and a flow meter for the base resin is branched at the injection pump outlet side of the base resin supply route. A return flow rate adjusting means is provided to configure a return path returning to the storage tank and to adjust the return flow rate, and a return flow rate adjustment means is provided to adjust the return flow rate from the base resin flowmeter based on the hardening agent supply flow rate change signal from the hardening agent flowmeter. By adjusting the return amount adjusting means based on the current base agent flow rate signal and controlling the ratio between the amount of the base agent fed to the injection pipe and the amount of curing agent fed to the injection pipe to a predetermined ratio. Solvable.

[Effect]

In the present invention, first, a flow meter for the base agent and a flow meter for the hardener are respectively disposed between the outlet side of the injection pump and the injection pipe of the feed route for the base agent and the hardener. therefore,
It is possible to accurately grasp the amount of each feed. Further, a return amount adjusting means is provided, which forms a return path that branches off at the injection pump outlet side of the main agent feeding route and returns to the main agent storage tank, and adjusts the return amount.

Therefore, by adjusting the return amount, the flow rate of the base agent in the direction of the injection pipe can be adjusted.

When injecting the chemical liquid, first, the base agent is constantly circulated through the return path formed in the base agent feed path at a predetermined pressure-feeding flow rate.

In this state, based on the curing agent feed flow rate change signal from the curing agent flowmeter and the current base resin flow rate signal from the base resin flowmeter, the return amount adjusting means is adjusted to The ratio of the amount of feed to the curing agent and the amount of curing agent fed to the injection pipe is controlled to a predetermined ratio. Therefore, if the flow rate of the curing agent is changed by the operator in the curing agent supply path, the curing agent flow meter detects this flow rate change, and based on this flow rate change signal, the current base agent flow rate from the base agent flow meter is detected. By adjusting the return amount of the main agent based on the flow rate signal, the ratio between the detection value of the main agent flowmeter and the detection value of the B path flowmeter is controlled to be a predetermined ratio.

In this way, by adjusting only the flow rate of the hardening agent, the flow rate of the base resin is adjusted based on the current flow rate signal of the base resin from the base resin flowmeter, so the feeding amount of the base resin and hardener can be adjusted with high precision. The ratio can be kept at a predetermined ratio.

Furthermore, in the present invention, as described above, the base agent is constantly circulated at a predetermined flow rate and pressure in the return path formed in the base agent feed path, so it responds sensitively to the adjustment of the return amount adjusting means. Since the flow rate is adjusted in the direction of the injection pipe, there is no time delay and highly accurate adjustment is possible.

Further, since the return amount is adjusted while observing the detection value of the main agent flow meter, the flow rate adjustment is also performed with high precision.

[Specific configuration of the invention]

Hereinafter, the present invention will be explained in detail based on specific examples of the present invention.

FIG. 1 shows a schematic diagram of a liquid drug injection system according to the present invention. The water glass W is housed in a water glass storage tank 1, and the water glass supply pipe 5.6 (hereinafter referred to as
This system is referred to as route A), and is fed to the injection pipe 19 inserted into the ground G, where it is injected into the ground G. On the other hand, the hardening agent P mixed with the water glass W is a hardening agent for slow setting in which the hardening agent tank 2 for slow setting contains the hardening agent for slow setting P1, and the hardening agent for instant setting in which the hardening agent for instant setting P is stored. A tank 3 is installed at the same time, and a curing agent P is selected as appropriate depending on the ground properties of the ground G, and is fed to the injection pipe 19 via the curing agent supply pipe 9 (hereinafter, this system is referred to as route B). ), the water glass W and the water glass W are combined at the confluence part 18 in front of the injection pipe 19 or in the pipe, and are injected into the surrounding ground G.

The present chemical injection system will be explained in detail below.

The water glass W accommodated in the water glass storage tank 1 is supplied by a multiple pump 10 which also serves to supply a curing agent and is disposed in the middle of a first water glass supply pipe that communicates with the storage tank 1.
It is designed to be sent to the injection pipe side. The water glass supply pipe 5 on the downstream side from the multiple pump 10 is provided with a three-way valve 11 that constitutes a return amount adjusting means according to the present invention. A return pipe 12 that communicates with one of the branch passages of this three-way valve 11 and returns to the water glass storage tank 1
The second water glass supply pipe 6 leading to the injection pipe 19 is connected to the remaining one branch path. It should be noted that a concentration meter 4a may be provided in the first water glass supply pipe, as shown by the chain line, for checking the concentration of the water glass W, if necessary.

A concentration meter 14, a main agent flow meter 15, and a pressure gauge 16 are arranged in the middle of the second water glass supply pipe 6 leading from the three-way valve 11 to the injection pipe 19. The detection unit F is configured together with the curing agent flowmeter 17. The data detected in this detection section F is sent to a three-pen type recorder 23, where the concentration, flow rate, and pressure are recorded over time, and further sent to the controller 24 via this three-pen type recorder 23. This controller 24 controls the three-way valve 11 based on the detected value of the detection unit F, and also controls a three-way valve I3, which will be described later, which switches the hardening agents P1 and P2 according to the soil properties. It also constitutes a general injection management unit that also handles such matters.

Note that 25 connected to the three-pen recorder 23 is a data recorder for storing the concentration, flow rate, and pressure signals.

On the other hand, the curing agent P is a curing agent P for slow setting.

A slow-setting hardening agent tank 2 and an instant-setting hardening agent P2 are accommodated.
A hardening agent tank 3 for instant setting is installed, and a hardening agent supply pipe 7 from the hardening agent tank 2 for slow setting and a hardening agent supply pipe 8 from the hardening agent tank 3 for instant setting are respectively installed. ,
They are combined at the three-way valve 13, and the curing agent PP2 is appropriately selected according to the ground properties by operating the three-way valve 13 by the controller 24. Note that, as shown by the chain line, densitometers 4b and 4c may be provided in the middle of the curing agent supply pipe 7.8 to check the concentration, if necessary.

For feeding the curing agent P, a multiple pump 10 which also serves as a water glass feeder for route A is used. For example, it is desirable to adopt a method such as inverter control or mechanical rotation speed control.

Hardening agent supply pipe 9 leading to injection pipe 19 via the three-way valve 13
A curing agent flowmeter 17 constituting the detection section F is disposed in the middle. Further, the detection section F includes a curing agent supply pipe 9.
Similarly to the main agent supply pipe 6, a concentration meter, a pressure gauge, etc. can also be provided on the side.

Note that 20, 21, and 22 are pressure gauges provided between the main agent supply pipe 6 and the curing agent supply pipe 9.

When injecting a drug solution under such a drug solution injection system,
First, the water glass W is constantly connected to the return pipe 12 during injection of the chemical solution.
It is circulated through a circulation line made up of.

Next, the three-way valve 13 is controlled by the controller 24 to select the curing agent P, P2, and the selected curing agent P is fed toward the injection pipe 19 by the multiple pump 10. be done. The amount of the curing agent P fed is measured over time by a curing agent flowmeter 17 and sent to the controller 24 . The controller 24 controls the preset mixing ratio (curing agent/base agent).
Based on this, the target feed rate of the base agent in the A route is determined, and the three-way valve 11 is controlled so that the indicated value of the base agent flow meter 15 disposed in the A route becomes the target feed rate. There is. Therefore, since the feed rate of the base agent W is always adjusted in accordance with the feed rate of the hardener P, the mixing ratio of the base agent and the hardener is always maintained at a predetermined ratio, and the chemical solution injected into the ground G. The gelation time is constantly maintained.

〔Effect of the invention〕

As explained in detail above, according to the present invention, it is possible to easily and highly accurately control the mixing ratio of the base agent and curing agent to a predetermined ratio when changing the injection amount of the chemical solution without bothering the operator. Therefore, the gelation time can be constantly maintained.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of a drug injection system according to the present invention, and FIG.
3 and 3 show schematic diagrams of a conventional liquid drug injection system. DESCRIPTION OF SYMBOLS 1... Water glass storage tank, 2... Hardening agent tank for slow setting, 3... Hardening agent tank for instant setting, 5... Water glass first supply pipe, 6... Water glass second Supply pipe, 9... Hardening agent supply pipe, 10... Multiple pump, II... 3-way valve, 12... Return pipe, 14... Concentration meter, 15...
...Main agent flow meter, 16...Pressure gauge, 17...Curing agent flow meter, 19...Injection pipe, 23...3 pen type recorder, 24...Controller patent applicant Front engineering Co., Ltd. Agent Patent Attorney Yoshihisa Nagai Diagram

Claims (1)

[Claims] (1) In a chemical injection method in which a base agent and a curing agent are injected into the surrounding ground from an injection pipe in a 1.5-shot or 2-shot method using an injection pump through mutually independent feeding routes, the base agent and A flow meter for the base resin and a flow meter for the hardener are respectively arranged between the injection pump outlet and the injection pipe in the hardening agent supply route, and a flow meter for the base resin is branched at the injection pump outlet side of the base resin supply route. A return amount adjusting means is provided which configures a return path returning to the storage tank and adjusts the return amount, and adjusts the current flow rate from the main agent flow meter based on the curing agent supply flow rate change signal from the curing agent flow meter. The return amount adjusting means is adjusted based on the base agent flow rate signal to control the ratio between the amount of the base agent fed to the injection pipe and the amount of curing agent fed to the injection tube to a predetermined ratio. A method for controlling the mixing ratio of an injected drug solution.