JP2023064246A - Control method, reinforcement method, purification method, construction, and method of repairing construction - Google Patents

Abstract

To appropriately control water in and/or on the ground.SOLUTION: A control method provided herein comprises: providing a region having water in and/or on the ground with an ion source material containing at least one of a first compound capable of generating cations that constitute a poorly soluble salt and a second compound capable of generating anions that constitutes a poorly soluble salt; and precipitating the poorly soluble salt around the ion source material to change at least one of the flow rate, flow direction, and retention volume of water in and around pores.SELECTED DRAWING: Figure 1

Description

The present disclosure relates to technology for controlling water in the ground and on the surface.

Pollution and disasters may occur due to groundwater. For example, when toxic substances leaked from industrial waste disposal sites or radioactive waste disposal sites are mixed with groundwater, rivers, lakes, seas, and surrounding soils can be contaminated with toxic substances. See Patent Document 1). In addition, the infiltration of groundwater may loosen the ground and cause landslide disasters, or damage structures such as embankments.

"Development of methods for removing iron and heavy metal elements from mine wastewater by applying iron concretization process", Eiichi Yoshida, Koshi Yamamoto, Ippei Maruyama, Nagoya University Museum Report, http://www.num.nagoya-u. ac.jp/media/report/docs/037_04.pdf, August 30, 2021

Installation of impermeable walls in the ground to impermeable groundwater requires a great amount of construction time and cost. There is a demand for a technology that effectively controls groundwater with a simpler method.

The present disclosure has been made in view of such problems, and an object thereof is to provide a technology for appropriately controlling water in the ground and on the surface of the ground.

In order to solve the above problems, a control method according to one aspect of the present disclosure includes a first compound capable of generating cations that constitute a sparingly soluble salt in a region where water exists in at least one of the ground and the surface of the ground; and a step of providing an ion supply material containing at least one of the second compounds capable of generating anions constituting the sparingly soluble salt; and C. at least one of flow direction and retention volume is changed.

Another aspect of the present disclosure is a reinforcement method. In this method, at least one of a first compound capable of generating cations constituting a sparingly soluble salt and a second compound capable of generating anions constituting a sparingly soluble salt is placed on at least one of the ground and the surface. providing an ion donor containing one; and reinforcing at least one of the ground and the ground surface by precipitating a sparingly soluble salt around the ion donor.

Yet another aspect of the present disclosure is a purification method. In this method, at least one of a first compound capable of generating cations constituting a sparingly soluble salt and a second compound capable of generating anions constituting a sparingly soluble salt is placed on at least one of the ground and the surface. a step of providing an ion supply material containing one; and a step of reducing harmful ions by forming and precipitating harmful ions present around the ion supply material together with cations or anions to form sparingly soluble salts. , provided.

Yet another aspect of the disclosure is a workpiece. The workpiece is present in a region where water exists in at least one of the ground and the surface of the ground, and contains a first compound capable of generating cations that form the sparingly soluble salt and anions that form the sparingly soluble salt. An ion donor containing at least one of the producible second compounds, and a sparingly soluble salt existing around the ion donor.

Yet another aspect of the present disclosure is a method of repairing a workpiece. The method comprises adding an ion donor in the vicinity of the refractory salt of the workpiece.

Yet another aspect of the present disclosure is a method of repairing a workpiece. The method comprises the steps of providing a new hole proximate the hole in the workpiece and providing an ion source within the new hole.

According to the present disclosure, it is possible to appropriately control water in the ground and on the surface.

1 is a diagram schematically showing a configuration of groundwater control equipment according to an embodiment of a work piece of the present disclosure; FIG. It is a figure which shows roughly the structure of another example of the groundwater control equipment which concerns on embodiment. It is a figure which shows roughly the structure of another example of the groundwater control equipment which concerns on embodiment. It is a figure which shows roughly the structure of another example of the groundwater control equipment which concerns on embodiment. It is a figure which shows roughly the structure of another example of the groundwater control equipment which concerns on embodiment. It is a figure which shows roughly the structure of another example of the groundwater control equipment which concerns on embodiment. It is a figure which shows roughly the structure of another example of the groundwater control equipment which concerns on embodiment. It is a figure which shows roughly the structure of another example of the groundwater control equipment which concerns on embodiment. It is a figure which shows roughly the structure of another example of the groundwater control equipment which concerns on embodiment. It is a figure which shows roughly the structure of another example of the groundwater control equipment which concerns on embodiment. It is a figure which shows roughly the structure of another example of the groundwater control equipment which concerns on embodiment. 4 is a flow chart showing a procedure of a groundwater control method according to an embodiment; It is a flowchart which shows the procedure of the restoration|restoration method of the groundwater control equipment which concerns on embodiment.

In the present disclosure, techniques for controlling the flow rate, flow direction, retention volume, etc. of water existing underground or on the surface of the earth will be described. In the control method according to the embodiment of the present disclosure, a first compound capable of generating cations constituting a sparingly soluble salt and a sparingly soluble salt are added to a region where water exists in at least one of the ground and the surface of the ground. An ion source is provided that includes at least one of the second compounds capable of producing constituent anions. At least one of the flow rate, flow direction, and retention amount of water is changed by precipitation of the sparingly soluble salt around the ion supply material.

Water that can be controlled by the control method of the present disclosure is all water that exists underground or on the surface of the earth, regardless of whether it is seawater or freshwater. According to the control method of the present disclosure, water infiltrated into the ground from rivers, ponds, lakes, waterways, seas, canals, etc., and water generated in large amounts on the ground surface due to rainfall, typhoons, tornadoes, flooding of rivers, etc. It is possible to control infiltrated water, water existing in rivers, ponds, lakes, waterways, seas, canals, etc., and water generated in large amounts on the ground surface due to rainfall, typhoons, tornadoes, flooding of rivers, etc.

When controlling groundwater, seepage water, and the like existing in the ground, the ion supply material may be provided in the ground such as soil, ground, bedrock, seabed, and the like. When controlling river water, seawater, etc. existing on the ground surface, the ion supply material may be provided on the ground surface or in the ground that is in contact with river water, seawater, or the like. As will be described later, the ions supplied from the ion supply material diffuse into the surroundings and deposit a sparingly soluble salt. It is desirable that

FIG. 1 schematically shows the configuration of a groundwater control system according to an embodiment of a work piece of the present disclosure. When a hazardous substance leaks from a facility 1 such as an industrial waste disposal site or a radioactive waste disposal site located in an area where groundwater 2 exists, the leaked hazardous substance may be mixed into the groundwater 2 . In this embodiment, in order to reduce the inflow of groundwater 2 mixed with harmful substances into rivers, lakes, seas, areas where pollution should be avoided, etc., groundwater control equipment 3 is provided upstream of those areas.

The groundwater control equipment 3 includes a boring hole 4 provided in an area where the groundwater 2 exists, an ion supplying material 5 provided inside the boring hole 4, and a flame generated by the ions supplied from the ion supplying material 5. a soluble salt 6; The ion supply material 5 contains at least one of a first compound capable of generating cations constituting the sparingly soluble salt 6 and a second compound capable of generating anions constituting the sparingly soluble salt 6 . In and around the borehole 4, the sparingly soluble salt 6 is precipitated from the ions supplied from the ion supply material 5, so that at least a part of the flow path of the groundwater 2 is blocked inside and around the borehole 4. , the flow rate of the groundwater 2 to the downstream area is reduced.

In the example of FIG. 1, a plurality of boreholes 4 are provided at short intervals, and at least part of the sparingly soluble salt 6 deposited between adjacent boreholes 4 is integrated to form a wall of the groundwater control equipment 3. . Thereby, the flow rate of the groundwater 2 to the downstream area is further reduced. Part of the groundwater whose flow is blocked by the wall stays upstream, and part of it flows around the outside of the wall. Therefore, inside the groundwater control equipment 3, the flow rate of the groundwater 2 decreases as the sparingly soluble salt 6 is formed over the plurality of boreholes 4, and outside the groundwater control equipment 3, the flow rate of the groundwater 2 is reduced by the amount of the decrease inside the groundwater control equipment 3. increase. In addition, the amount of groundwater 2 that stays increases on the upstream side of the groundwater control equipment 3 including the wall, and the amount of groundwater 2 that stays on the downstream side decreases. The groundwater 2 dammed up by the groundwater control equipment 3 may be pumped up and transported to a treatment facility for treating hazardous substances, or may be guided to flow toward the place where the treatment facility is located. .

When the ion supply material 5 contains the first compound, the cations forming the sparingly soluble salt are produced from the first compound, and when the ion supply material 5 contains the second compound, the sparingly soluble salt is produced from the second compound The anions that make up the salt are each eluted. When the ion supply material 5 contains both the first compound and the second compound, sparingly soluble salts are produced from the eluted cations and anions. When the ion supply material 5 contains the first compound, a sparingly soluble salt is produced from the eluted cations and anions contained in the surrounding groundwater or the like. When the ion supply material 5 contains the second compound, a sparingly soluble salt is produced from the eluted anions and the cations contained in the surrounding groundwater.

The ions supplied from the ion supply material 5 diffuse into gaps and cracks in the bedrock and strata around the borehole 4, so that the sparingly soluble salt 6 is formed even in the gaps and cracks around the borehole 4. be done. As a result, not only the inside of the boring hole 4 but also the voids around the boring hole 4 can be blocked with the sparingly soluble salt 6 . As shown in FIG. 1, by providing a plurality of boreholes 4 and closing the gaps between the adjacent boreholes 4 with a sparingly soluble salt 6, the surface including the plurality of boreholes 4 can be substantially impermeable wall. can function as As a result, it is possible to effectively control the flow rate, flow velocity, flow direction, amount of retention, etc. of the groundwater 2 while greatly reducing the construction period and construction cost compared to installing impermeable walls in the ground.

The ions supplied from the ion supply material 5 diffuse due to the concentration gradient of the ions, but since the concentration of the ions originally present around the borehole 4 is usually low, no external force is applied. The ions can also easily diffuse into gaps and cracks in the bedrock around the borehole 4 . In addition, since the ions are dissolved in water and diffuse, ions can be easily diffused into extremely small gaps and cracks at the atomic and molecular level regardless of pore water pressure even in deep underground. Since the soluble salt 6 can be formed and blocked, the flow of the groundwater 2 inside and around the borehole 4 can be blocked more reliably.

The width L (cm) of the reaction edge of the sparingly soluble salt 6 formed around the borehole 4, the speed V (cm/s) at which the reaction edge is formed, and the ion diffusion coefficient D (cm ² / s), the relationship D=VL is established. For example, when a plurality of boreholes 4 are provided at intervals of 20 cm, the diffusion of ions and the deposition of sparingly soluble salts progress from each borehole 4, and when the width of the reaction edge becomes approximately 10cm, the reaction from the adjacent borehole 4 Edges overlap. Assuming that the diffusion coefficient D of ions around the borehole 4 is 10 ^{−5 to −6} cm ² /s, it takes about several months to a year for the reaction edges from the adjacent boreholes 4 to overlap. It will be. The intervals and arrangement patterns of the plurality of boreholes 4 are determined by the diffusion coefficient of ions around the boreholes 4, the hydraulic conductivity, the flow rate and flow velocity of the groundwater 2, the period until the gaps between the adjacent boreholes 4 are closed, and the groundwater It may be designed according to the purpose for which the control facility 3 is provided.

The sparingly soluble salt may have sufficiently low solubility in water at the location where the borehole 4 is provided, is chemically stable, and does not pollute the surrounding natural environment. Examples include calcium carbonate, magnesium carbonate, and iron carbonate. (II) Carbonates such as (siderite, siderite), double salts such as calcium magnesium carbonate (CaMg(CO ₃ ) ₂ , dolomite, dolomite), sulfates such as calcium sulfate, and the like may also be used. . The sparingly soluble salt may be appropriately selected according to the location where the borehole 4 is provided. For example, calcium carbonate can change into calcium hydrogen carbonate, which has a relatively high solubility in water, through a chemical reaction with carbon dioxide. An ion supply material 5 that supplies ions that form a sparingly soluble salt other than calcium may be provided in the borehole 4 . In addition, since calcium carbonate can be dissolved by a chemical reaction with acid, when the structural material is to be installed in an environment with a relatively low pH, iron, whose hydroxides and oxides are poorly soluble in water, can be used. (III) An ion supply material 5 for supplying ions such as ions may be provided in the borehole 4 . As a result, even if the calcium carbonate in and around the borehole 4 is dissolved by the acid present around the borehole 4, the acid is neutralized by the calcium carbonate and the pH rises, resulting in a poorly soluble hydroxide, Since the oxide precipitates, the voids inside and around the borehole 4 can be blocked by the precipitated hydroxide and oxide. Ions for forming poorly soluble hydroxides and oxides may be, for example, iron (III) ions, aluminum ions, copper (II) ions, zinc ions, manganese ions, and the like.

When calcium carbonate is deposited as a sparingly soluble salt, strontium, which is an alkaline earth metal like calcium and has similar chemical properties to calcium, is incorporated into calcium carbonate. As a result, even if the groundwater 2 contains radioactive isotopes of strontium, the radioactive isotopes of strontium can be removed from the groundwater 2 because they can be precipitated together with calcium carbonate. In addition, by coprecipitating other radioactive substances with the sparingly soluble salt 6 or by adsorbing them to the sparingly soluble salt 6 and immobilizing them, not only is the diffusion of contaminated water containing radioactive substances suppressed, but also the contaminated water and can cleanse the ground or surface.

When calcium carbonate is precipitated as the sparingly soluble salt, the first compound is capable of generating calcium ions, has sufficiently high solubility in water at the temperature of the environment in which the ion supply material is provided, and can be used in the surrounding natural environment. Any material that does not contaminate is acceptable. The first compound may be, for example, calcium chloride (CaCl ₂ ), calcium nitrate (Ca(NO ₃ ) ₂ ), calcium bicarbonate (Ca(HCO ₃ ) ₂ ), calcium oxide (CaO), and the like.

When calcium carbonate is precipitated as the sparingly soluble salt, the second compound is capable of producing at least one of carbonate ions and hydrogen carbonate ions, and has sufficient solubility in water at the temperature of the environment in which the ion supply material is provided. It is acceptable if it is high and does not pollute the surrounding natural environment. The second compound may be, for example, sodium bicarbonate (NaHCO ₃ ), potassium bicarbonate (KHCO ₃ ), ammonium bicarbonate (NH ₄ HCO ₃ ), and the like.

By providing the ion supplying material 5 in the ground or on the surface of the ground, harmful ions contained in the ground or on the surface of the ground can be precipitated as sparingly soluble salts to purify the ground or the surface of the ground. For _example , crushed gypsum board is sometimes sprinkled on the ground to improve the ground. It is converted to hydrogen sulfide by , which causes corrosion of concrete etc. In addition, when the concentration of sulfate ions increases, sodium sulfate precipitates as a decahydrate (Na ₂ SO ₄ .10H ₂ O: mirabilite) or an anhydrous salt (Na ₂ SO ₄ : tenardite). Since the formation generates a large expansion pressure, the formation of large amounts of decahydrate salts in concrete, bricks, etc. may cause expansion failure. In addition, since ettringite (3CaO.Al ₂ O 3.3CaSO _{4.32H 2} O), which _is generated by the reaction between the sulfate and the aluminate phase contained in the cement, also has the property of expanding, Delayed formation of ettringite can cause expansion failure. Thus, sulfate ions are harmful ions in that they cause deterioration of structures constructed of concrete or the like. By providing the ion supplying material 5 capable of supplying calcium ions in the soil, the sulfate ions contained in the soil can be precipitated as calcium sulfate, thereby reducing the sulfate ions contained in the soil and purifying the soil. can do. In this case, the first compound may be calcium chloride (CaCl ₂ ), calcium nitrate (Ca(NO ₃ ) ₂ ), calcium bicarbonate (Ca(HCO ₃ ) ₂ ), or the like. Further, according to the technology of the present embodiment, by precipitating, coprecipitating, or adsorbing harmful substances such as heavy metal ions and radioactive substances existing in the ground and on the surface, It can also reduce the concentration of harmful substances contained in it and purify the ground and surface.

Both the first compound and the second compound may be present together in the ion source 5 . For example, the first compound and the second compound may be mixed in the ion supply material 5 . Both the first compound and the second compound may be present separately in the ion donor 5 . For example, at least one of the first compound and the second compound may be enclosed in a capsule or the like and contained in the ion supplying material 5 . The capsule may be made of a material that dissolves in water or the like.

The ion supply material 5 may further include a base material containing at least one of the first compound and the second compound. The base material may be a material that has fluidity that allows it to be injected into the boring hole 4 and that is hardened by chemical reactions such as hydration and polymerization, heating, cooling, drying, light, and the like after injection. The base material may be, for example, cement, mortar, concrete, or the like, may be thermosetting resins such as epoxy resins, silicone compounds, polyol compounds, and phenol compounds, or may be thermoplastic resins such as acrylic resins. or a mixture thereof. The base material may be a material that slowly releases at least one of the cations that form the first compound and the anions that form the second compound. For example, the matrix may be an epoxy resin. Note that the ion supply material 5 in which the base material is solidified may be inserted into the boring hole 4 .

The ion supply material 5 may contain an ion exchange resin on which ions to be supplied are adsorbed. In this case, in accordance with the type of ions to be supplied, and the components, amounts, pH, etc. of chemical substances dissolved in the groundwater around the borehole 4, ions that release ions in an appropriate amount and supply rate Exchange resins can be selected or designed.

The ion supply material 5 may include a capsule that encloses and slowly releases ions to be supplied. The ions encapsulated in the capsule may be contained as the first compound or the second compound, or may be contained as an ion-exchange resin on which the ions are adsorbed. In this case as well, the type of ions to be supplied and the composition, amount, pH, etc. of chemical substances dissolved in the groundwater around the borehole 4 are used to release ions at an appropriate amount and supply rate. Capsule material, thickness, shape, etc. can be selected or designed.

The ion supply material 5 may contain a sparingly soluble substance that serves as a core for depositing a sparingly soluble salt. Thereby, precipitation of the sparingly soluble salt 6 can be promoted. The sparingly soluble substance may be any substance that has sufficiently low solubility in water at the temperature of the boring hole 4 in which the ion supply material 5 is provided, is chemically stable, and does not pollute the surrounding natural environment. carbonates such as magnesium carbonate and iron (II) carbonate (siderite, siderite); double salts such as calcium magnesium carbonate (CaMg(CO ₃ ) ₂ , dolomite, dolomite); sulfates such as calcium sulfate; , metal hydroxides such as iron hydroxide, metals such as iron, and minerals such as sand and rocks. The sparingly soluble substance may be the same as the sparingly soluble salt to be precipitated, or may be different.

After the refractory salt 6 precipitates and the voids inside and around the borehole 4 are blocked, the voids and voids inside and around the borehole 4 are formed due to external forces such as earthquakes, crustal movements, tidal currents, and typhoons. Even if a crack occurs, if the ions supplied from the ion supply material 5 remain, the ions supplied from the ion supply material 5 will diffuse into the voids and cracks inside and around the borehole 4. Voids and fissures can be blocked by precipitated sparingly soluble salts upon reaction with counterions. As described above, according to the technique of the present embodiment, the groundwater control equipment 3 can be provided with a self-recovery function, so that the durability of the groundwater control equipment 3 can be improved. It is desirable that the ion supply material 5 be designed so that the ions supplied from the ion supply material 5 remain even after the voids inside and around the borehole 4 are closed. In addition to the ion source 5 designed to supply the ions necessary to block the voids in and around the borehole 4 immediately after the borehole 4 is placed, the voids in and around the borehole 4 are also provided. Easily soluble salts containing ions, ion exchange resins, etc. are enclosed in a container such as a capsule that breaks and releases the contents when an external force that causes damage such as cracks or cracks is applied. Alternatively, the ion supply material 5 may be arranged inside the borehole 4 .

A pH adjusting material for increasing the pH of groundwater may be provided inside the borehole 4 . When the groundwater 2 contains iron ions, as the pH of the groundwater 2 is increased by the pH adjusting material, the iron ions are converted into α-, β-, γ-, or δ-iron oxyhydroxide and iron oxide (III). , iron (III) hydroxide, or the like, and is adsorbed on the surface of the pH-adjusting material. As a result, the concentration of iron ions contained in the groundwater 2 can be reduced, and the flow rate of the groundwater 2 can be reduced. Iron oxide is known to act to coprecipitate heavy metal compounds and the like when it precipitates or colloids. Therefore, not only iron ions contained in the groundwater 2 but also heavy metal ions such as lead (Pb), cadmium (Cd) and arsenic (As) and light metal ions such as aluminum (Al) can be reduced in concentration. . It is also known that alpha nuclides such as uranium form a complex and dissolve in water under acidic conditions, but precipitate under alkaline conditions. Therefore, the concentration of α-nuclides such as uranium can be reduced as the pH of the groundwater 2 is increased by the pH-adjusting material. Similarly, the concentration of other harmful substances that are soluble in water under acidic conditions but precipitate under alkaline conditions can be reduced. The pH adjuster may contain at least one of calcium carbonate, calcium hydrogen carbonate, calcium oxide, and calcium hydroxide. The pH adjusting material may include concrete, cement, cement clinker, alite, belite, aluminate, ferrite, and the like. The pH adjuster may be any compound such as sodium carbonate, sodium bicarbonate, sodium hydroxide, calcium acetate, sodium acetate, etc. whose aqueous solution exhibits alkalinity. The pH adjusting material may be the same compound as the ion supplying material 5, or may be a different compound. The pH adjusting material may be provided inside the boring hole 4 provided with the ion supplying material 5 or may be provided inside the boring hole 4 not provided with the ion supplying material 5 . A plurality of boring holes 4 may be provided, and the boring holes 4 having the ion supplying material 5 provided therein and the boring holes 4 having the pH adjusting material provided therein may be separately provided. When a compound whose aqueous solution exhibits alkalinity is provided as the ion supply material 5, the ion supply material 5 may also serve as a pH adjuster.

The boring hole 4 may be provided to a depth that penetrates the permeable ground and reaches the impermeable ground. In addition, when an existing borehole or underground structure exists in an area where the groundwater 2 exists, and the ion supply material 5 is provided inside the borehole 4 or in the contact portion between the underground structure and the ground, a new It is not necessary to provide a boring hole in

FIG. 2 schematically shows the configuration of another example of groundwater control equipment according to the embodiment. In order to reduce the inflow of groundwater 2 mixed with hazardous substances leaked from facilities 1 existing in an area where groundwater 2 exists, groundwater control equipment 3 is provided upstream of the area downstream of groundwater 2. In the example of this figure, a plurality of boring holes 4 are provided at wider intervals than the example shown in FIG. 1, and the sparingly soluble salt 6 is not integrated. Also in this case, the flow rate of the groundwater 2 decreases inside the groundwater control equipment 3, and the flow rate of the groundwater 2 increases outside. In addition, the amount of groundwater 2 that stays increases on the upstream side of the groundwater control equipment 3, and the amount of groundwater 2 that stays on the downstream side decreases. As a result, pollution of rivers and soil in downstream areas of groundwater can be suppressed.

FIG. 3 schematically shows the configuration of another example of the groundwater control equipment according to the embodiment. If the foundation ground of the embankment 11 that constitutes the embankment 10 of a river or the like is highly permeable ground, rainwater or river water may permeate the foundation ground and cause water leakage or piping. By providing the groundwater control equipment 3 in the foundation ground, it is possible to suppress permeation of rainwater and river water into the foundation ground. Inside the groundwater control equipment 3, the flow rate of the groundwater 2 infiltrated by rainwater or river water decreases, while the flow rate of the groundwater 2 increases outside. In addition, the amount of groundwater 2 that stays increases on the river side of the groundwater control equipment 3, and the amount of groundwater 2 that stays on the land side decreases. In addition, by providing the ion supply material 12 on the surface of the bank 11 and depositing the sparingly soluble salt 13 on the surface of the bank 11, rainwater and river water can be prevented from permeating into the bank 11. Thereby, the strength and durability of the embankment 10 can be improved.

FIG. 4 schematically shows the configuration of another example of groundwater control equipment according to the embodiment. A groundwater control facility 3 is provided upstream of the pollution source 7 in order to reduce the inflow of the groundwater 2 to the pollution source 7 when the pollution source 7 containing harmful substances exists in the area where the groundwater 2 exists. The groundwater control equipment 3 changes the flow direction of the groundwater 2 to bypass the pollution source 7 . The flow rate of the groundwater 2 decreases inside the groundwater control equipment 3, and the flow rate of the groundwater 2 increases outside. In addition, the amount of groundwater 2 that stays increases on the upstream side of the groundwater control equipment 3, and the amount of groundwater 2 that stays on the downstream side decreases. Thereby, contamination of the groundwater 2 can be suppressed. Similarly, when a vulnerable area with loose ground such as an embankment exists in an area where the groundwater 2 exists, the groundwater control equipment 3 is provided upstream of the vulnerable area in order to similarly reduce the inflow of the groundwater 2 into the vulnerable area. be done. As a result, it is possible to suppress the occurrence of sediment disasters due to the collapse of the vulnerable area due to the infiltration of the groundwater 2 .

FIG. 5 schematically shows the configuration of another example of groundwater control equipment according to the embodiment. In order to reduce the inflow of the groundwater 2 to the pollution source 7 and the outflow of the groundwater 2 from the pollution source 7 when the pollution source 7 containing hazardous substances such as industrial waste is disposed in the area where the groundwater 2 exists, A groundwater control facility 3 is provided around the pollution source 7 . The groundwater control equipment 3 changes the flow direction of the groundwater 2 to bypass the pollution source 7 . The flow rate of the groundwater 2 decreases inside the groundwater control equipment 3, and the flow rate of the groundwater 2 increases outside. Further, the amount of groundwater 2 from the pollution source 7 increases inside the area surrounded by the groundwater control equipment 3 , and the amount of groundwater 2 from the pollution source 7 decreases downstream of the groundwater control equipment 3 . As a result, it is possible to suppress the inflow of the polluted groundwater 2 into the downstream area, and to suppress the occurrence of landslides caused by the collapse of the pollution source 7 due to the infiltration of the groundwater 2 .

FIG. 6 schematically shows the configuration of another example of groundwater control equipment according to the embodiment. A groundwater control facility 3 is installed along a flow path for causing the groundwater 2 to flow avoiding the pollution source 7 when the pollution source 7 containing hazardous substances such as industrial waste is disposed in an area where the groundwater 2 exists. be provided. The groundwater control equipment 3 changes the flow direction of the groundwater 2 to bypass the pollution source 7 . The flow rate of the groundwater 2 decreases inside the groundwater control equipment 3, and the flow rate of the groundwater 2 increases outside. In addition, around the pollution source 7 located inside the groundwater control equipment 3, the amount of the groundwater 2 stagnation decreases, and on the downstream side of the groundwater control equipment 3, the stagnation amount of the groundwater 2 decreases. As a result, it is possible to suppress the inflow of the polluted groundwater 2 into the downstream area, and to suppress the occurrence of landslides caused by the collapse of the pollution source 7 due to the infiltration of the groundwater 2 .

FIG. 7 schematically shows the configuration of another example of the groundwater control equipment according to the embodiment. When the underground structure 8 under construction exists in the area where the groundwater 2 exists, the groundwater control equipment 3 is provided upstream of the underground structure 8 in order to reduce the inflow of the groundwater 2 into the underground structure 8. be done. The flow rate of the groundwater 2 decreases inside the groundwater control equipment 3, and the flow rate of the groundwater 2 increases outside. In addition, the amount of groundwater 2 that stays increases on the upstream side of the groundwater control equipment 3, and the amount of groundwater 2 that stays on the downstream side decreases. This can prevent the groundwater 2 from interfering with the construction of the underground structure 8 .

FIG. 8 schematically shows the configuration of another example of the groundwater control equipment according to the embodiment. A groundwater control facility 3 is provided along a channel for allowing the groundwater 2 to flow into the dam 9 when the dam 9 exists in an area where the groundwater 2 exists. The flow direction of the groundwater 2 is changed toward the dam 9 by the groundwater control equipment 3 . The flow rate of the groundwater 2 decreases inside the groundwater control equipment 3, and the flow rate of the groundwater 2 increases outside. In addition, around the dam 9 located between the groundwater control equipment 3, the amount of the groundwater 2 that remains increases, and on the opposite side of the dam 9 across the groundwater control equipment 3, the amount of the groundwater 2 that remains decreases. Thereby, the groundwater 2 can be guided around the dam 9 .

FIG. 9 schematically shows the configuration of another example of groundwater control equipment according to the embodiment. A groundwater control facility 3 is installed in advance in the ground that is expected to liquefy when an earthquake or the like occurs. As the sparingly soluble salt 6 precipitates and increases in volume, the surrounding gravel is compressed, and the gaps between the gravel are clogged with the sparingly soluble salt 6, and the groundwater that has accumulated in the gaps between the gravel is driven out, and the amount of retention increases. Decrease. This will strengthen the ground.

FIG. 10 schematically shows the configuration of another example of groundwater control equipment according to the embodiment. The groundwater control equipment 3 is provided in advance on the loose ground where there is a possibility of collapse. In this case as well, the sparingly soluble salt 6 precipitates and increases in volume, thereby compressing the surrounding gravel and clogging the gaps between the gravel with the sparingly soluble salt 6, thereby expelling the groundwater that has accumulated in the gaps between the gravel. , the amount of retention decreases. As a result, the ground can be reinforced, and the occurrence of landslides can be suppressed.

FIG. 11 schematically shows the configuration of another example of groundwater control equipment according to the embodiment. Before constructing the underground structure 8, the groundwater control equipment 3 is installed in advance in the ground with high water content. As the sparingly soluble salt 6 precipitates and increases in volume, the surrounding gravel is compressed, and the gaps between the gravel are clogged with the sparingly soluble salt 6, and the groundwater that has accumulated in the gaps between the gravel is driven out, and the amount of retention increases. Decrease. As a result, the underground structure 8 can be constructed on the reinforced ground, so that the strength and durability of the underground structure 8 can be improved.

FIG. 12 is a flow chart showing the procedure of the control method according to the embodiment. A boring hole 4 is provided in an area where water exists in at least one of the ground and the surface (S10). An ion supply material 5 is provided inside the boring hole 4 (S12). A sparingly soluble salt 6 is precipitated from the ions supplied from the ion supply material 5 inside and around the borehole 4 (S14). The voids inside and around the borehole 4 are blocked by the sparingly soluble salt 6, and the flow rate, flow velocity, flow direction, retention volume, etc. of water existing in at least one of the ground and the surface are changed.

FIG. 13 is a flow chart showing procedures of a method for repairing groundwater control equipment according to the embodiment. After the groundwater control equipment 3 is installed, if it is found that the control of the groundwater by the groundwater control equipment 3 is insufficient by investigating the flow rate, flow velocity, flow direction, retention amount, etc. of the groundwater, or if the groundwater control equipment If it is found that the sparingly soluble salt 6 of 3 has a void or a crack, the groundwater control equipment 3 is repaired. An ion supply material 5 is added inside the boring hole 4 (S20). Further, a new boring hole 4 is provided near the existing boring hole 4 (S22), and an ion supply material 5 is provided inside the new boring hole 4 (S24). A sparingly soluble salt 6 is precipitated from the ions supplied from the newly provided ion supply material 5 (S26). The voids inside and around the borehole 4 are blocked by the sparingly soluble salt 6, and the flow rate, flow velocity, flow direction, retention volume, etc. of the groundwater are changed. Either one of S20 and S22 and S24 may be performed, or both may be performed.

The present disclosure has been described above based on the examples. It should be understood by those skilled in the art that this embodiment is an example, and that various modifications can be made to combinations of each component and each treatment process, and such modifications are within the scope of the present disclosure. .

In the embodiment, the sparingly soluble salt was precipitated around the sparingly soluble material, but a sparingly soluble compound other than the salt may be precipitated. In this case, the ion donor contains a compound that is readily soluble in water, but chemically reacts with other compounds present in the environment in which the ion donor is disposed to form a sparingly soluble precipitate. may For example, an ion supply material that constitutes a structure to be built underground near a volcano may contain a compound that generates zinc ions, and react with hydrogen sulfide present in the surroundings to precipitate zinc sulfide. .

A summary of one aspect of the present disclosure is as follows.

In the control method of the present disclosure, a first compound capable of producing cations that form a sparingly soluble salt and anions that form a sparingly soluble salt are added to a region where water exists in at least one of the ground and the surface of the ground. At least one of the flow rate, flow direction, and retention amount of water is changed by the step of providing an ion supply material containing at least one of the producible second compound and the precipitation of the sparingly soluble salt around the ion supply material. and As a result, it is possible to appropriately control the water that exists in the ground and on the surface of the ground, and to suppress the occurrence of disasters and pollution. Moreover, since the water present in the ground and on the surface of the ground can be controlled by a simpler method, the construction period and construction cost can be reduced. The ion supply material may be provided in the ground such as soil, ground, bedrock, seabed, etc. where groundwater exists, or may be provided in the surface or the ground in contact with river water, seawater, or the like.

The control method further comprises the step of providing a hole in the region, and the step of providing an ion donor includes the step of providing an ion donor inside the hole. may change at least one of flow rate, flow direction, and retention of water in and around the hole. As a result, it is possible to appropriately control the water that exists in the ground and on the surface of the ground, and to suppress the occurrence of disasters and pollution. In addition, in the present disclosure, the term “hole” includes bottomed ones. "Providing" an ion donor includes "filling", "injecting", "inserting", "inserting", "enclosing", etc. according to the form of the ion donor.

The ion source may be provided upstream of the region where water influx is to be reduced. An ion source may be provided downstream of the region where water outflow is to be reduced. An ion source may be provided along a channel that directs water. As a result, it is possible to appropriately control the water that exists in the ground and on the surface of the ground, and to suppress the occurrence of disasters and pollution.

The ion supply material is present at a plurality of locations in the above region, and at least one of the flow rate, flow direction, and retention amount of water may be changed by depositing a sparingly soluble salt between adjacent ion supply materials. . As a result, it is possible to appropriately control the water that exists in the ground and on the surface of the ground, and to suppress the occurrence of disasters and pollution.

At least a portion of the sparingly soluble salt deposited between adjacent ion donors may be integrated to form a wall. This makes it possible to change at least one of the flow rate, flow direction, and retention amount of water existing underground or on the surface of the earth.

A plurality of holes may be provided and the spacing between the plurality of holes may be determined based on the diffusion coefficient of at least one of the cations and anions at the locations where the plurality of holes are provided. As a result, it is possible to appropriately control the water present in the ground and on the surface of the ground, and to reduce the construction period and construction costs.

The distance between the plurality of holes is defined by the width L (cm) of the reaction edge of the sparingly soluble salt formed around the hole, the speed at which the reaction edge is formed V (cm/s), and the diffusion coefficient D (cm ² /s). may be determined based on the relational expression D=VL between As a result, it is possible to appropriately control the water present in the ground and on the surface of the ground, and to reduce the construction period and construction costs.

The sparingly soluble salt may be calcium carbonate. As a result, it is possible to improve the durability of the equipment for controlling the water existing in the ground or on the surface of the ground while suppressing material costs.

Strontium contained in water may be taken up when calcium carbonate precipitates. As a result, radioactive isotopes of strontium contained in water present in the ground or on the surface of the ground can be reduced.

The ion donor may include a base material and at least one of the first compound and the second compound mixed in the base material. As a result, the construction period and construction costs can be reduced.

The base material may contain an epoxy resin. As a result, ions can be gradually released from the first compound and the second compound mixed in the base material, so that the voids inside and around the borehole 4 can be blocked more reliably.

A pH adjuster may be provided inside the pores to increase the pH of the water. As a result, iron ions, heavy metal ions, and the like contained in water present in the ground and on the surface of the ground can be reduced.

In the reinforcement method of the present disclosure, a first compound capable of generating cations constituting a sparingly soluble salt and a second compound capable of generating anions constituting a sparingly soluble salt are placed in at least one of the ground and the surface. providing an ion donor containing at least one of the compounds; and precipitating a sparingly soluble salt around the ion donor to reinforce at least one of the ground and the ground surface. As a result, it is possible to appropriately reinforce the ground and the surface of the ground and suppress the occurrence of disasters. Also, the construction period and construction costs can be reduced.

In the purification method of the present disclosure, a first compound capable of generating cations that constitute a poorly soluble salt and a second compound capable of generating anions that constitute a poorly soluble salt are placed in at least one of the ground and the surface of the ground. Harmful ions are reduced by the steps of providing an ion supply material containing at least one of the compounds, and causing harmful ions present around the ion supply material to form and precipitate cations or anions and sparingly soluble salts. and As a result, it is possible to properly purify the ground and the surface of the earth and suppress the occurrence of disasters and pollution. Also, the construction period and construction costs can be reduced.

The harmful ions may be sulfate ions. Thereby, corrosion of concrete etc. can be prevented and durability can be improved.

The workpiece of the present disclosure is present in a region where water exists in at least one of the ground and the surface of the ground, and includes a first compound capable of generating a cation that constitutes a sparingly soluble salt, and a negative compound that forms a sparingly soluble salt. An ion donor containing at least one of the second compounds capable of generating ions, and a sparingly soluble salt existing around the ion donor. As a result, it is possible to appropriately control the water that exists in the ground and on the surface of the ground, and to suppress the occurrence of disasters and pollution. Moreover, since the water present in the ground and on the surface of the ground can be controlled by a simpler method, the construction period and construction cost can be reduced.

The ion donor may be present within pores present in the regions described above. As a result, it is possible to appropriately control the water that exists in the ground and on the surface of the ground, and to suppress the occurrence of disasters and pollution. Moreover, since the water present in the ground and on the surface of the ground can be controlled by a simpler method, the construction period and construction cost can be reduced.

The method of repairing a workpiece of the present disclosure comprises adding an ion donor in the vicinity of the sparingly soluble salt. As a result, it is possible to improve the durability of equipment for controlling water present in the ground or on the surface of the ground, and to appropriately control the water present in the ground or on the surface over a long period of time.

A method of repairing a workpiece of the present disclosure includes the steps of providing a new hole in the vicinity of the hole and providing an ion source inside the new hole. As a result, it is possible to improve the durability of equipment for controlling water present in the ground or on the surface of the ground, and to appropriately control the water present in the ground or on the surface over a long period of time.

1 facility, 2 groundwater, 3 groundwater control facility, 4 borehole, 5 ion supply material, 6 sparingly soluble salt, 7 pollution source, 8 underground structure, 9 dam, 10 embankment, 11 embankment body, 12 ion supply material, 13 difficulty soluble salt.

Claims (18)

A first compound capable of producing cations that form the sparingly soluble salt, and a second compound capable of producing anions that form the sparingly soluble salt, in a region where water exists in at least one of the ground and the surface of the earth. providing an ion source comprising at least one of the compounds;
at least one of flow rate, flow direction, and retention amount of the water is changed by precipitation of the sparingly soluble salt around the ion supply material;
A control method comprising: further comprising providing a hole in said region;
providing the ion source comprises providing the ion source within the hole;
The control method according to claim 1, wherein at least one of a flow rate, a flow direction, and a retention amount of the water inside and around the holes is changed by the precipitation of the sparingly soluble salt inside and around the holes. 3. The control method according to claim 1, wherein the ion supply material is provided upstream of the region where the inflow of water is to be reduced. 4. The control method according to any one of claims 1 to 3, wherein the ion supply material is provided downstream of the region where outflow of water is to be reduced. 5. The control method according to any one of claims 1 to 4, wherein the ion supply material is provided along a flow path for guiding the water. The ion supply material exists at a plurality of locations in the region, and at least one of the flow rate, flow direction, and retention amount of the water is changed by depositing the sparingly soluble salt between the adjacent ion supply materials. The control method according to any one of claims 1 to 5. 7. The control method according to claim 6, wherein at least a portion of said sparingly soluble salt deposited between said adjacent ion donors is integrated to form a wall. A plurality of said holes are provided,
8. The control method according to any one of claims 2 to 7, wherein the intervals between the plurality of holes are determined based on the diffusion coefficient of at least one of the cations and the anions at locations where the plurality of holes are provided. The distance between the plurality of holes is defined by the width L (cm) of the reaction edge of the sparingly soluble salt formed around the hole, the speed V (cm/s) at which the reaction edge is formed, the diffusion coefficient D (cm 9. The control method according to claim 8, wherein the control method is defined based on the relational expression D=VL between ² /s). The sparingly soluble salt is calcium carbonate,
10. The control method according to any one of claims 1 to 9, wherein strontium contained in said water is taken in when calcium carbonate precipitates. 11. The control method according to any one of claims 1 to 10, wherein the ion supply material includes a base material and at least one of the first compound and the second compound mixed in the base material. 12. The control method according to any one of claims 2 to 11, wherein a pH adjusting material for increasing the pH of groundwater is provided inside the hole. At least one of a first compound capable of generating cations constituting the sparingly soluble salt and at least one of a second compound capable of generating anions constituting the sparingly soluble salt is contained in at least one of the ground and the surface. providing an ion source;
at least one of the ground and the ground surface is reinforced by precipitation of the sparingly soluble salt around the ion supply material;
A reinforcement method comprising: At least one of a first compound capable of generating cations constituting the sparingly soluble salt and at least one of a second compound capable of generating anions constituting the sparingly soluble salt is contained in at least one of the ground and the surface. providing an ion source;
a step in which the harmful ions present around the ion supply material are reduced by forming and precipitating the cations or anions and the sparingly soluble salt;
A purification method comprising: A first compound that exists in a region where water exists in at least one of the ground and the surface of the ground and is capable of generating cations that constitute the sparingly soluble salt, and a second compound that is capable of generating anions that constitute the sparingly soluble salt. an ion donor containing at least one of the compounds of 2;
the sparingly soluble salt present around the ion donor;
Workpiece with 16. The workpiece of claim 15, wherein said ion source is present within pores present in said region. 17. The method of repairing a workpiece according to claim 15 or 16, comprising adding the ion donor in the vicinity of the sparingly soluble salt. providing a new hole in the vicinity of said hole;
providing the ion donor inside the new hole;
17. The method of repairing a workpiece according to claim 16, comprising:

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