JP7095840B2 - Fluorescent dye concentration control system and fluorescent dye concentration control method - Google Patents

Description

The present invention relates to a fluorescent dye concentration control system and a fluorescent dye concentration control method.

For the purpose of purifying contaminated ground, ground improvement, heat storage, water shielding, etc., an injection liquid containing an injection agent such as a purifying agent, an activator, or a supercooled aqueous solution may be injected into the ground. In addition, for the purpose of groundwater flow survey, etc., an injection liquid to which an injection agent is not added may be injected into the ground.

Here, in order for the injection agent added to the injection liquid to function effectively when purifying the contaminated ground, it is necessary to appropriately control the concentration of the injection agent in the groundwater. However, in order to measure the concentration of the injectant in the groundwater, it may be necessary to bring the collected groundwater to a test room and measure it with a large-scale facility, which is troublesome. In addition, there are cases where the measurement itself is difficult due to the low concentration of the injection agent, or even if the measurement is possible, it is difficult to determine whether or not the injection agent has arrived due to the dissolution or dispersion of the injection agent.

In order to solve this problem, for example, a method of estimating the concentration of the injection agent by adding an amount of fluorescent dye corresponding to the amount of the injection agent to the injection liquid and measuring the concentration of the fluorescent dye in the ground water in the in-situ is known. Has been done. Further, there is known a method of observing the groundwater flow in the ground by adding a fluorescent dye to the injection liquid as a tracer and measuring the concentration of the fluorescent dye in the groundwater at the time of groundwater flow survey or the like.

As an example, in Patent Document 1, an injection liquid to which an injection agent and a fluorescent dye (index agent) are added is injected into the ground from a water injection well (water injection means), and groundwater is pumped by a pumping well (pumping means). A ground injection concentration estimation system that returns to a water injection well is disclosed.

International Publication No. 2018/08996

In the ground injection agent concentration estimation system shown in Patent Document 1, an amount of fluorescent dye (index agent) corresponding to the amount of injection agent is added to the injection liquid, and the concentration of the fluorescent dye (index agent) in ground water is measured. By doing so, the concentration of the injectable agent is estimated and the concentration of the injectable agent in the ground water is controlled.

However, the fluorescent dye may remain in the groundwater returned to the water injection well, and it is difficult to control the fluorescent dye to the target concentration in the injection liquid injected from the water injection well to the ground.

In view of the above facts, an object of the present invention is to provide a fluorescent dye concentration control system and a fluorescent dye concentration control method capable of controlling a fluorescent dye to a target concentration in an injection liquid injected from a water injection means into the ground. ..

The fluorescent dye concentration control system according to the first aspect measures the concentration of the fluorescent dye in the ground at a water injection means for injecting an injection liquid to which the fluorescent dye is added into the ground and a place away from the water injection means. First concentration measuring device, a pumping means for pumping groundwater, a recirculation path for returning the groundwater pumped from the pumping means to the water injection means, and a recirculation path provided in the recirculation path and pumped from the pumping means. A water treatment device for treating the groundwater, a second concentration measuring device provided in the recirculation path and measuring the concentration of the fluorescent dye contained in the groundwater pumped from the pumping means, and the second concentration measuring device. It has a control device for controlling the amount of the fluorescent dye added to the injection liquid based on the concentration of the fluorescent dye measured in 1.

According to the above configuration, by injecting the injection liquid into the ground from the water injection means, it is possible to investigate the flow of groundwater, purify the contaminated ground, improve the ground, store heat, impermeable water, and the like. In addition, since the fluorescent dye is added to the injection liquid, the concentration of the fluorescent dye in the ground can be measured by the first concentration measuring device at a place away from the water injection means, so that the groundwater flow can be observed and the injection agent can be used. It is possible to estimate the concentration of.

Here, the concentration of the fluorescent dye contained in the ground water treated by the water treatment device and returned to the water injection means is measured by the second concentration measuring device provided in the return path, and the concentration of the fluorescent dye contained in the ground water is measured. Based on this, the control device controls the amount of fluorescent dye added to the injectate. As a result, the fluorescent dye can be controlled to a target concentration in the injection liquid injected from the water injection means into the ground.

The fluorescent dye concentration control system according to the second aspect is the fluorescent dye concentration control system according to the first aspect , in which an injection agent is added to the injection liquid, and the fluorescent dye is said in the ground. It is said to be a substance that behaves like an injection.

According to the above configuration, the injection liquid to which the injection agent is added is injected from the water injection means into the ground and pumped by the pumping means to create a groundwater flow between the water injection means and the pumping means, and the injection liquid contaminates the groundwater, for example. The ground can be purified.

In addition, since the fluorescent dye is considered to be a substance that behaves in the ground in the same manner as the injection agent, the concentration of the fluorescent dye in the ground is measured by the first concentration measuring device at a place away from the water injection means. It is possible to estimate the concentration of the injection agent and control the concentration of the injection agent at a predetermined position in the ground.

The fluorescent dye concentration control system according to the third aspect is the fluorescent dye concentration control system according to the second aspect , wherein a plurality of different types of injections added to the injection liquid and a plurality of the injections are added. Each of the injection liquid has a plurality of different types of the fluorescent dyes added to the injection liquid, and the concentrations of the plurality of the fluorescent dyes are measured by the first concentration measuring device and the second concentration measuring device, respectively. ..

According to the above configuration, the concentration of the injection agent is estimated by measuring the concentration of each of the plurality of types of fluorescent dyes with the first concentration measuring device at a place away from the water injection means, and the concentration is estimated at a predetermined position in the ground. The concentration of the injectable agent can be controlled respectively.

Further, by measuring the concentration of the plurality of types of fluorescent dyes contained in the groundwater returned to the water injection means with the second concentration measuring device, the amount of each of the plurality of types of fluorescent dyes added to the injection liquid is controlled. be able to. As a result, in the injection liquid injected from the water injection means into the ground, it is possible to control the concentration of each of the plurality of types of fluorescent dyes to the target concentration with respect to the concentration of the plurality of types of injection agents.

In the fluorescent dye concentration control method according to the fourth aspect , the injection liquid to which the fluorescent dye is added is injected from the water injection means into the ground, and the concentration of the fluorescent dye in the ground at a place away from the water injection means is measured. , The ground water is pumped by a pumping means, the pumped ground water is treated and returned to the water injection means, and the concentration of the fluorescent dye contained in the pumped ground water is measured and contained in the measured ground water. The amount of the fluorescent dye added to the injection liquid is controlled based on the concentration of the fluorescent dye.

According to the above configuration, by injecting the injection liquid into the ground from the water injection means, it is possible to investigate the flow of groundwater, purify the contaminated ground, improve the ground, store heat, impermeable water, and the like. Further, since the fluorescent dye is added to the injection liquid, the underground state can be observed by measuring the concentration of the fluorescent dye in the ground at a place away from the water injection means.

Further, the concentration of the fluorescent dye contained in the ground water that has been treated and returned to the water injection means is measured, and the amount of the fluorescent dye added to the injection liquid is controlled based on the concentration of the fluorescent dye contained in the ground water. As a result, the fluorescent dye can be controlled to a target concentration in the injection liquid injected from the water injection means into the ground.

According to the fluorescent dye concentration control system and the fluorescent dye concentration control method according to the present invention, the fluorescent dye can be controlled to a target concentration in the injection liquid injected from the water injection means into the ground.

It is a top view which shows the schematic structure of the fluorescent dye concentration management system and the fluorescent dye concentration management method which concerns on 1st and 2nd Embodiment. It is a vertical sectional view which shows the schematic structure of the fluorescent dye concentration management system and the fluorescent dye concentration management method which concerns on 1st and 2nd Embodiment. It is a graph which shows the relationship between the light intensity and the wavelength of the excitation light and fluorescence in the fluorescent dye density control system and the fluorescent dye density control method which concerns on 1st Embodiment. It is a graph which shows the relationship between the light intensity and the wavelength of excitation light and fluorescence in the fluorescent dye concentration management system and the fluorescent dye concentration management method which concerns on 2nd Embodiment.

Hereinafter, the fluorescent dye concentration control system and the fluorescent dye concentration control method according to the first and second embodiments of the present invention will be described with reference to FIGS. 1 to 4. The description of common components represented by the same reference numerals in a plurality of drawings may be omitted.

[First Embodiment]
(overall structure)
As shown in FIGS. 1 and 2, the fluorescent dye concentration control system 10 of the present embodiment has a pumping well 14 (14A, 14B) as a pumping means constructed in an underground ground 12 and a water injection well 16 as a water injection means. It has (16A, 16B), observation wells 18 (18A to 18C), and an impermeable wall 20.

Further, above the ground surface GL, a first concentration measuring device 22 for measuring the concentration of the fluorescent dye in the groundwater collected from the observation well 18 and a recirculation of the groundwater pumped from the pumping well 14 back to the water injection well 16. A path 30 and a purification device 24 provided in the return path 30 are constructed.

(Underground ground)
The underground ground 12 is a ground below the ground surface GL, and has an aquifer 26 through which groundwater flows and an impermeable layer 28 through which groundwater does not flow, as shown in FIG. The portion of the underground ground 12 containing a reference value (for example, a value determined for each type of pollutant) or more is referred to as contaminated ground E.

"Contaminants" include organic substances such as tetrachlorethylene, trichlorethylene, cis-1,2-dichloroethylene, vinyl chloride monomer and benzene, inorganic compounds such as hexavalent chromium and cyanide, and oils such as mineral oils such as gasoline and light oil. It is a concept that includes.

In FIG. 2, the groundwater level HL is illustrated by a chain line, and the direction of the groundwater flow in the underground ground 12 is indicated by a broken line arrow. This groundwater flow is a flow generated by injecting an injection liquid containing an injection agent or the like, which will be described later, from the water injection well 16 into the underground ground 12, and further pumping the groundwater from the pumping well 14.

(Pump well)
The pumping well 14 is a pumping means for pumping groundwater from the underground ground 12, and can suck up the groundwater in the aquifer 26 by the pumping pump P and send it to the purification device 24.

In FIGS. 1 and 2, the pumping pump P is installed outside the pumping well 14, but this is for the purpose of explaining the configuration, and it is assumed that the pumping pump P is installed inside the pumping well 14. .. However, the pump P may be installed outside the pumping well 14. Further, the pumping well 14 is arranged between the contaminated ground E and the impermeable wall 20, and is buried in the underground ground 12 so that the depth at the lower end is equal to or less than the depth of the contaminated ground E.

In FIG. 1, for convenience of illustration, only two pumping wells 14A and 14B are shown, but the embodiment of the present invention is not limited to this, and any number of pumping wells 14 can be provided according to the size of the site and the like. It may be arranged as appropriate.

The pumping well 14 may be arranged on the contaminated ground E. Further, since the specific method of pumping by the pumping well 14, the shape and size of the pumping well 14, and the like are known, detailed description thereof will be omitted.

(Water injection well)
The water injection well 16 is a water injection means for injecting the injection liquid generated by the purification device 24 into the underground ground 12, and the injection liquid can be sent into the underground ground 12 by a pump or the like (not shown). Further, the water injection well 16 is a well arranged between the contaminated ground E and the impermeable wall 20 (opposite the pumping well 14 when viewed from the contaminated ground E), and the depth at the lower end is equal to or less than the depth of the contaminated ground E. It is buried in the underground ground 12 so as to be.

In FIG. 1, for convenience of illustration, only two water injection wells 16A and 16B are shown, but the embodiment of the present invention is not limited to this, and any number of water injection wells 16 can be provided according to the size of the site and the like. It may be arranged as appropriate.

The water injection well 16 may be arranged in the contaminated ground E. Further, since the specific method of injecting the injection liquid by the water injection well 16 and the shape, size, etc. of the water injection well 16 are known, detailed description thereof will be omitted.

(Observation well)
The observation well 18 is an observation means for observing an underground state, and is provided between the water injection well 16 and the pumping well 14 at a predetermined distance from the water injection well 16 and the pumping well 14. Here, the "underground state" indicates a state in the underground ground 12 at the position where the observation well 18 is buried, for example, the groundwater level, the ground temperature, the injection agent concentration and the fluorescent dye concentration in the groundwater, which will be described later. , Concentration of pollutants in groundwater, etc.

Various sensors (not shown) are installed in the observation well 18, and these sensors measure the above-mentioned groundwater level, ground temperature, fluorescent dye concentration in groundwater, and the like, and these measured values are described later in the purification device 24. It is transmitted to the control device 38 of the above by an electric signal.

These sensors are also installed inside the pumping well 14 and the water injection well 16. That is, the pumping well 14 and the water injection well 16 also function as observation means, respectively. Further, in FIGS. 1 and 2, the signal line connected to the control device 38 is not shown in order to avoid complicating the figure.

A pumping pump (not shown) is installed inside or outside the observation well 18, and groundwater at a predetermined depth of the observation well 18 is sampled, and the collected groundwater is pumped to the first concentration measuring device 22 installed on the ground. can do.

The observation wells 18 are buried at a plurality of locations in the underground ground 12 surrounded by the impermeable wall 20, and in FIG. 1, only three observation wells 18A, 18B, and 18C are shown for convenience of illustration. There is. However, the embodiment of the present invention is not limited to this, and an arbitrary number of observation wells 18 may be appropriately arranged according to the size of the site and the like.

(Immersion wall)
The impermeable wall 20 is an impermeable means of a steel sheet pile (sheet pile) arranged in the underground ground 12 so as to surround the periphery of the contaminated ground E, and blocks the flow of groundwater inside and outside the impermeable wall 20. .. That is, the flow of groundwater in the underground ground 12 "outside" of the impermeable wall 20 and the flow of groundwater in the underground ground 12 "inside" the impermeable wall 20 are prevented from affecting each other.

As shown in FIG. 2, the lower end of the impermeable wall 20 is embedded in the impermeable layer 28. As a result, the contaminated ground E is surrounded by the impermeable wall 20 and the impermeable layer 28, and the outflow of the contaminated material to the underground ground 12 outside the impermeable wall 20 is suppressed.

(1st concentration measuring device)
The groundwater inside the observation wells 18 (18A, 18B, 18C) is pumped to a predetermined depth by a pump (not shown) installed inside each well, and is sent to the first concentration measuring device 22 via a header (not shown). Sent.

The header is a collective piping member for combining multiple pipes into one, and which of the groundwater pumped from the three observation wells 18A, 18B, and 18C can be opened and closed by opening and closing solenoid valves and valves (not shown). It is possible to select whether to send the groundwater to the first concentration measuring device 22.

The first concentration measuring device 22 can measure the intensity of the light emitted by the fluorescent dye contained in the groundwater sent from the header. Specifically, for example, the groundwater is irradiated with excitation light from a light source device (not shown), and the light intensity C of the fluorescence generated by the fluorescent dye contained in the groundwater is measured by a spectroscope (not shown). As a specific example, FIG. 3 shows the respective light intensities of the excitation light wavelength L1 and the fluorescence wavelength L2.

The concentration of the fluorescent dye can be calculated from the light intensity C. If the concentration of the fluorescent dye is expressed as F (C) as a function of the light intensity C, for example, the estimated concentration X of the activator as an injection agent can be calculated. It can be expressed as follows. The coefficient α is derived from the difference in adsorption / decomposition characteristics measured by carrying out the adsorption / decomposition tests of the activator and the fluorescent dye, respectively.

(Estimated concentration X of activator) = α × [Concentration F (C) of fluorescent dye] ... (1 formula)
α: coefficient

(Purification device)
The purification device 24 is a device for purifying the groundwater pumped from the pumping well 14 and returning it to the underground ground 12 by adding an injection agent or the like described later, and is a second concentration measuring device 32, a water treatment device 34, and an addition device. It includes a tank 36 and a control device 38.

(Second concentration measuring device)
In the present embodiment, the second concentration measuring device 32 has the same configuration as the first concentration measuring device 22, and measures the light intensity D emitted by the fluorescent dye contained in the groundwater sent from the pumping well 14. be able to.

Specifically, for example, the groundwater is irradiated with excitation light from a light source device (not shown), and the light intensity D of the fluorescence generated by the fluorescent dye contained in the groundwater is measured by a spectroscope (not shown). From this light intensity D, the density F (D) of the fluorescent dye can be calculated as in the case of the first density measuring apparatus 22.

(Water treatment equipment)
The water treatment device 34 separates (and extracts) volatile pollutants and oils from the groundwater pumped from the pumping well 14. Further, the water treatment device 34 heats the purified groundwater by a heater (not shown) whose temperature is controlled by the control device 38 described later. By heating the groundwater with the water treatment device 34, it is possible to promote the growth of the degrading microorganisms that biodegrade the pollutants in the underground ground 12 and to increase the activity of the degrading microorganisms.

(Addition tank)
The addition tank 36 adds at least one of a purifying agent or an activator as an injection agent and a fluorescent dye to the groundwater to generate an injection liquid. Specifically, at least one of the purifying agent or the activator and the fluorescent dye are added to the groundwater inside the addition tank 36 from a charging device (not shown) controlled by the control device 38 described later, and the mixture is stirred and injected. An injection liquid to be injected from the well 16 into the underground ground 12 is generated.

Here, the "purifying agent" is a substance that decomposes a pollutant in the underground ground 12, and as an example, "degrading microorganisms" such as dehalococcoides and dehalosulfide that biodegrade the pollutant. , There are "chemical decomposition agents" that chemically decompose pollutants. Specific examples of the chemical decomposition agent include "reducing agents" such as iron-based slurrys and "oxidizing agents" such as hydrogen peroxide, sulfates, Fenton's reagents, permanganic acid, and percarbonates.

The "activator" is a substance that activates the biodegradation of degrading microorganisms, and a hydrogen sustained-release agent, an organic substance, a pH adjuster, a micronutrient, a trace element, or the like can be used.

Of these, organic substances include formic acid, acetic acid, propionic acid, butyric acid, lactic acid or citric acid or their sodium salts, potassium salts or calcium salts, glucose, fructose, galactose, lactose, maltose, trehalose, peptone, tripton, yeast extract. , Fumic acid, vegetable oil and the like can be used.

As the pH adjuster, sodium hydrogen carbonate, sodium such as sodium carbonate, potassium carbonate, hydrogen carbonate, ammonium hydroxide, ammonium carbonate, sodium tripolyphosphate, disodium hydrogen phosphate, trisodium phosphate and the like can be used. Can be used.

Further, as the micronutrient, vitamin B12, vitamin B1, pantothenic acid, biotin, folic acid and the like can be used. Further, as the trace element, Co, Zn, Fe, Mg, Ni, Mo, B and the like can be used. In this embodiment, an activator (yeast extract) is used as an injection agent.

The fluorescent dye is a substance that behaves like a purifying agent or an activator in the underground ground 12 (including the contaminated ground E), and is in the in-situ (contaminated ground) even in a low concentration state without using a large-scale facility. It is a substance whose concentration can be easily measured on E or in a nearby building.

As the fluorescent dye, uranin, eosin, rhodamine B, rhodamine WT, pyranine, amino G acid, sodium naphthoate, sulfordamine G and the like can be used, but in this embodiment, eosin is used.

Here, "having the same behavior as a purifying agent or an activator" specifically means that the density, viscosity, adsorption / decomposition characteristics, etc. of the fluorescent dye with respect to groundwater are similar to those of the purifying agent or the activator. .. The adsorption / decomposition characteristics of the fluorescent dye and the adsorption / decomposition characteristics of the purifying agent or the activator may have a difference to the extent that the above-mentioned coefficient α can be calculated. Further, "similarity" includes not only the case of perfect agreement but also the degree of slight difference that can be measured by the test.

The fluorescent dye is used as a substance (tracer) for measuring the concentration of the purifying agent or the activator in the groundwater of the underground ground 12. By measuring the concentration of the fluorescent dye, the concentration of the purifying agent or the activator in the groundwater of the underground ground 12 can be estimated.

(Control device)
The control device 38 includes information such as groundwater level and ground temperature measured by sensors (not shown) installed in the observation well 18, the water injection well 16, and the pumping well 14, as well as the first concentration measuring device 22 and the second concentration. Information such as the concentration of the fluorescent dye contained in the groundwater measured by the measuring device 32 is received as an electric signal. Then, the water treatment device 34, the addition tank 36, and the pump P are driven and controlled according to the received information.

(Method for estimating the concentration of injection agent)
In the fluorescent dye concentration control system 10 of the present embodiment, as shown in FIG. 2, first, in the addition tank 36, the injection liquid to be injected from the water injection well 16 into the underground ground 12 is mixed with an activator (yeast extract) as an injection agent. , Fluorescent dye (eosin) is added. Here, the concentration of the activator (yeast extract) in the injection solution is made equal to the concentration of the fluorescent dye. That is, the relationship between the respective concentrations in the injectable solution is expressed as follows.

(Concentration of activator): (Concentration of fluorescent dye) = 1: 1 ... (2 formulas)

Next, the injection liquid to which the activator (yeast extract) and the fluorescent dye (eosin) are added is injected from the addition tank 36 into the water injection well 16. In the injection liquid injected into the water injection well 16, the pump P pumps groundwater from the pumping well 14 to generate a water gradient of the groundwater, so that the water injection well 16 to the underground ground 12 and the contaminated ground E at a target speed. Spread to.

At this time, since the activator (yeast extract) and the fluorescent dye (eosin) have the same density, viscosity, adsorption / decomposition characteristics, etc. with respect to groundwater, they diffuse at almost the same speed. However, since the activator (yeast extract) and the fluorescent dye (eosin) have a slight difference in adsorption / decomposition characteristics, a difference in concentration in groundwater occurs in the process of diffusing into the underground ground 12. Therefore, the relationship between the respective concentrations in groundwater is estimated as follows using the coefficient α according to the adsorption / decomposition characteristics.

(Estimated concentration of activator): (Concentration of fluorescent dye) = α: 1 ... (3 formulas)

Next, at a place away from the water injection well 16, groundwater inside the observation well 18 is collected by a pump (not shown) provided inside the observation well 18 and sent to the first concentration measuring device 22. The light intensity C of the fluorescent dye (eosin) is measured by the first concentration measuring device 22, and the concentration F (C) of the fluorescent dye (eosin) is calculated.

Here, when the estimated concentration X of the activator (yeast extract) and the concentration F (C) of the fluorescent dye (eosin) are substituted on the left side of (Equation 3), it is expressed as follows.

(Estimated concentration X of activator): [Concentration F (C) of fluorescent dye] = α: 1 ... (4 formulas)

By modifying this (4 formulas), the above-mentioned (1 formula) can be obtained, and the estimated concentration X of the activator (yeast extract) at a predetermined position in the underground ground 12 can be calculated. The amount of the injection liquid injected into the water injection well 16 is controlled by the control device 38 based on the estimated concentration X of the activator (yeast extract).

(Method of controlling the concentration of fluorescent dye)
Further, the groundwater in the underground ground 12 is pumped from the pumping well 14 by the pump P and sent to the purification device 24 through the return path 30. At this time, the fluorescent dye may remain in the recirculated groundwater.

The light intensity D of the residual fluorescent dye is measured by the second concentration measuring device 32 of the purifying device 24, and the density F (D) of the fluorescent dye is calculated. Further, the concentration F (D) of the fluorescent dye calculated by the second concentration measuring device 32 is transmitted to the control device 38 by an electric signal.

The control device 38 newly adds the fluorescent dye (yield) to the injection liquid in the addition tank 36 based on the concentration of the fluorescent dye received and the amount of the activator (yeast extract) newly added to the injection liquid in the addition tank 36. The amount of eosin) is controlled to control the fluorescent dye to the target concentration.

In the present embodiment, the "target concentration" of the fluorescent dye refers to the concentration of the fluorescent dye with respect to the concentration of the injection agent, and is equal to the concentration of the activator (yeast extract) as represented by (Equation 3). Has been done. However, the target concentration of the fluorescent dye can be appropriately determined according to the injection agent used, the type of the fluorescent dye, and the adsorption / decomposition characteristics, and can be changed during the purification work of the contaminated ground E.

For example, when the ratio of the yeast extract concentration to the fluorescent dye concentration in the injection solution is (a: 1), the estimated concentration of yeast extract is calculated by multiplying the right side of (1 formula) by a. This value of a is arbitrary, but since the fluorescent dye is not expected to have a pollutant decomposition effect, the fluorescent dye may be contained to the extent necessary for calculating the concentration of the yeast extract, for example, about a = 60. But it may be.

(Action / effect)
According to the present embodiment, the injection liquid to which the activator (yeast extract) as an injection agent is added is injected from the water injection well 16 into the underground ground 12 and pumped by the pumping well 14, so that the water injection well 16 and the pumping well are pumped. A groundwater flow can be created between 14 and 14, and the biodegradation of the degrading microorganisms can be activated by the activator (yeast extract) to promote the purification of the contaminated ground E.

In addition, a fluorescent dye (eosin) is added to the injection solution together with the injection agent (activator). Therefore, at a place away from the water injection well 16, the concentration of the injection agent is estimated by measuring the concentration of the fluorescent dye in the underground ground 12 with the first concentration measuring device 22, and the predetermined position in the underground ground 12 is estimated. It is possible to control the concentration of the injectable agent in.

Further, according to the present embodiment, the concentration of the fluorescent dye contained in the ground water returned to the water injection well 16 is measured by the second concentration measuring device 32 of the purification device 24, and is based on the concentration of the fluorescent dye contained in the ground water. , The control device 38 controls the amount of the fluorescent dye added to the injection liquid. Thereby, in the injection liquid injected from the water injection well 16 to the underground ground 12, the fluorescent dye can be controlled to the target concentration with respect to the concentration of the injection agent.

[Second Embodiment]
In the first embodiment, one kind of activator and one kind of fluorescent dye were added as an injection to the injection liquid, but in the second embodiment, two kinds of activators and two kinds of fluorescence as an injection agent were added to the injection liquid. Add each dye.

Here, as the two types of fluorescent dyes to be added to the injection liquid for each injection agent, the band of the excitation light wavelength L1 and the band of the fluorescence wavelength L2 of each other are sufficient, for example, the fluorescent dyes S and T shown in FIG. It is preferable to select the ones that are far from each other. As a result, the excitation light wavelengths L1 (S) and the fluorescence wavelength L2 (S) of the fluorescent dye S and the excitation light wavelengths L1 (T) and the fluorescence wavelength L2 (T) of the fluorescent dye T are prevented from interfering with each other. Can be done.

In this embodiment, for example, yeast extract and hydrogen sustained-release agent (polylactic acid ester) are used as the activator (injector), and eosin is used as the fluorescent dye S and fluorescent dye T is used as the fluorescent dye S for each activator (injector). Amino G acid is used.

According to this embodiment, the yeast extract and the hydrogen sustained-release agent (polylactic acid) are measured by measuring the concentrations of the two types of fluorescent dyes S and T contained in the ground water with the first concentration measuring device 22 shown in FIG. 2, respectively. The concentration of (ester) can be estimated respectively. Thereby, the concentration of the activator (injector) at a predetermined position in the underground ground 12 can be controlled respectively.

Further, by measuring the concentrations of the two types of fluorescent dyes S and T contained in the groundwater with the second concentration measuring device 32 shown in FIGS. 1 and 2, respectively, the two types of fluorescent dyes S and T added to the injection liquid are added. Each amount of T can be controlled. Thereby, in the injection liquid, the fluorescent dyes S and T (eosin and amino G acid) can be controlled to the target concentrations, respectively, with respect to the concentrations of the yeast extract and the hydrogen sustained-release agent (polylactic acid ester).

The combination of the purifying agent, the activator, and the fluorescent dye described above is arbitrary and can be used in various combinations. Further, both the "purifying agent" and the "activator" may be used as the injection agent, and a plurality of types of the purifying agent may be used, or a plurality of types of the activator may be used alone. However, it is desirable not to use a reducing agent as a purifying agent (for example, an iron-based slurry) in combination with an activator.

[Other embodiments]
Although the first and second embodiments of the present invention have been described above, the present invention is not limited to such embodiments, and various other embodiments are possible within the scope of the present invention. In addition, the configurations of the above embodiments can be combined as appropriate.

For example, in the first and second embodiments, the contaminated ground E of the one aquifer 26 formed above the impermeable layer 28 of the underground ground 12 is purified, but a plurality of layers divided by the impermeable layer are purified. It may be configured to purify the contaminated ground of the aquifer.

When purifying the contaminated ground of a plurality of aquifers, the pumping well 14, the water injection well 16, the observation well 18, the first concentration measuring device 22, and the purifying device 24 shown in FIGS. 1 and 2 are used as the aquifer. By installing each, the aquifer can be purified.

Here, when purifying a plurality of aquifers divided by an impermeable layer, a fluorescent dye flows out from one aquifer to the other aquifer, and a plurality of types of fluorescent dyes are mixed in the aquifer. May be done. Therefore, as in the second embodiment, the fluorescent dyes added to the injection liquids injected into the water-bearing layer are those in which the band of the excitation light wavelength L1 and the band of the fluorescence wavelength L2 are sufficiently separated from each other. Is preferable.

As a result, the concentration of the injection agent is estimated by measuring the concentration of the plurality of fluorescent dyes of different types by the first concentration measuring device 22, and the concentration of the injection agent is controlled at a predetermined position in the ground. be able to.

Further, by measuring the concentrations of the plurality of fluorescent dyes of different types by the second concentration measuring device 32 of the purification device 24, the amount of each of the plurality of fluorescent dyes added to the injection liquid can be controlled. As a result, in the injection liquid injected from the water injection well 16 into the underground ground 12, it is possible to control the plurality of fluorescent dyes to the target concentration with respect to the concentration of the injection agent.

When the thickness of the impermeable layer that divides the aquifer is sufficiently large and there are no cracks, the same type of fluorescent dye may be used for the injection liquid to be injected into the aquifer of a plurality of layers. Even if the same type of fluorescent dye is used, it is unlikely that these fluorescent dyes are mixed, so that the concentration of each fluorescent dye can be measured. Further, the control devices of the purification devices installed for each of the aquifers may be combined into one.

Further, in the first and second embodiments, the second concentration measuring device 32 is provided on the upstream side (pumping well 14 side) of the water treatment device 34 in the purification device 24. However, the second concentration measuring device 32 may be provided at least on the upstream side (pumping well 14 side) of the addition tank 36, and may be provided between the water treatment device 34 and the addition tank 36.

Further, in the first and second embodiments, the second concentration measuring device 32 has the same configuration as the first concentration measuring device 22. However, the second concentration measuring device 32 may have a configuration capable of measuring the concentration of the fluorescent dye, and may have a configuration different from that of the first concentration measuring device 22. Further, for example, as shown by the arrow 40 of the alternate long and short dash line in FIG. 2, one of the first concentration measuring device 22 and the second concentration measuring device 32 may not be provided and the other may be used in combination.

Further, in the first and second embodiments, the material of the impermeable wall 20 is a steel sheet pile (sheet pile), and the lower end of the impermeable wall 20 is rooted in the impermeable layer 28. However, the lower end of the impermeable wall 20 does not have to be embedded in the impermeable layer 28, and the material of the impermeable wall 20 may be, for example, frozen soil, clay, concrete, a cement improved body, or the like.

Further, the impermeable wall 20 does not necessarily have to be provided. When the impermeable wall 20 is not provided, it is desirable to arrange the water injection well 16 on the upstream side of the groundwater flow and the pumping well 14 on the downstream side. As a result, the injection liquid injected from the water injection well 16 into the underground ground 12 can be smoothly permeated into the underground ground 12.

Further, when the groundwater is purified by using a decomposing microorganism that biodegrades a pollutant as a purifying agent, a nutrient salt or oxygen may be mixed or a new decomposing microorganism may be mixed. Further, in order to smoothly inject the injection liquid through the water injection well 16, a flocculant may be mixed.

Further, for example, in the first embodiment, the groundwater is heated by the heater in the water treatment device 34, but the embodiment of the present invention is not limited to this. For example, the groundwater may be heated by exchanging heat between the heat medium of the air conditioner (not shown) and the groundwater purified by the water treatment device 34, such as exhaust heat from the contaminated ground E or a nearby building. It may be heated by using steam or the like. In addition, when the degrading microorganism is active with a predetermined activity, heating is not always necessary.

Further, in the above embodiment, the fluorescent dye concentration control system 10 and the fluorescent dye concentration control method are used when purifying the contaminated ground E. However, the fluorescent dye concentration control system and the fluorescent dye concentration control method according to the present invention can also be used for investigation of groundwater flow, ground improvement, heat storage, water shielding, and the like.

For example, when the fluorescent dye concentration control system and the fluorescent dye concentration control method according to the present invention are used for the groundwater flow survey, only the fluorescent dye is added to the injection liquid without adding the injection agent and injected into the groundwater 12. ..

Specifically, a fluorescent dye solution in which a fluorescent dye is dissolved in water is injected into the underground ground 12 from the water injection well 16 as an injection liquid, and the concentration of the fluorescent dye contained in the groundwater pumped from the observation well 18 is measured. , Investigate groundwater flow. In this case, the pumping well 14 is unnecessary, and the groundwater pumped from the observation well 18 as a pumping means is returned to the water injection well 16 through the return path 30.

Further, for example, when the fluorescent dye concentration control system and the fluorescent dye concentration control method according to the present invention are used in a ground improvement system for measures against liquefaction of underground ground 12, an overcooled aqueous solution or bubble mixed water is used as an injection agent. Use a solidifying material or the like.

Further, when used in a heat storage system for utilizing the geothermal heat of the underground ground 12, a heat storage material such as a supercooled aqueous solution is used as an injection agent. Further, when used in an impermeable system for lowering the groundwater level when excavating the underground ground 12, a supercooled aqueous solution or a solidifying material is used as an injection agent. As described above, the fluorescent dye concentration control system and the fluorescent dye concentration control method according to the present invention can be carried out in various embodiments.

10 Fluorescent dye concentration control system 12 Underground ground (ground)
14 Pumping well (an example of pumping means)
16 Water injection well (an example of water injection means)
22 1st concentration measuring device 30 Reflux path 32 2nd concentration measuring device 34 Water treatment device 38 Control device

Claims (4)

A water injection means for injecting an injection liquid containing a fluorescent dye into the ground,
A first concentration measuring device that collects groundwater in the ground and measures the concentration of the fluorescent dye at a place away from the water injection means.
A pumping means for pumping groundwater downstream from the position of an observation well for collecting groundwater whose concentration of the fluorescent dye is measured by the first concentration measuring device in the flow direction of the injection liquid injected into the ground. ,
A recirculation route for returning the groundwater pumped from the pumping means to the water injection means,
A water treatment device provided in the reflux path to treat the groundwater pumped from the pumping means, and a water treatment device.
A second concentration measuring device provided in the reflux path and measuring the concentration of the fluorescent dye contained in the groundwater pumped from the pumping means, and a second concentration measuring device.
The injection amount of the injection liquid is controlled based on the measurement result measured by the first concentration measuring device, and the injection amount of the injection liquid and the concentration of the fluorescent dye measured by the second concentration measuring device are used. A control device that controls the amount of the fluorescent dye added to the injection liquid, and
Fluorescent dye concentration control system. The fluorescent dye concentration control system according to claim 1, wherein an injection agent is added to the injection liquid, and the fluorescent dye is a substance that exhibits the same behavior as the injection agent in the ground. A plurality of different types of injections added to the injection, and
A plurality of different types of fluorescent dyes added to the injection solution for each of the plurality of injection agents,
Have,
The concentrations of the plurality of fluorescent dyes are measured by the first concentration measuring device and the second concentration measuring device, respectively.
The fluorescent dye concentration control system according to claim 2. Inject the injection liquid to which the fluorescent dye is added from the water injection means into the ground,
Groundwater in the ground at a place away from the water injection means was collected and the concentration of the fluorescent dye was measured.
In the flow direction of the injection liquid injected into the ground, the groundwater downstream from the position of the observation well for collecting the groundwater whose concentration of the fluorescent dye is measured is pumped by a pumping means.
The pumped groundwater is treated and returned to the water injection means, and the concentration of the fluorescent dye contained in the pumped groundwater is measured.
The injection amount of the injection liquid is controlled based on the measurement result measured by the collected ground water, and the injection amount of the injection liquid and the concentration of the fluorescent dye measured by the pumped ground water are used as the injection liquid. Controlling the amount of the fluorescent dye added,
Fluorescent dye concentration control method.

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