JP2006328321A - Method for granulating water-containing soil and agent for treating water-containing soil - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for granulating water-containing soil capable of corresponding even to the water-containing soil with high water content by a small amount in a short time; and to provide an agent for treating the water-containing soil. <P>SOLUTION: The method for granulating the water-containing soil involves (A) mixing (a) a water-soluble polymer containing a carboxy group (including a carboxylic acid salt group) and a sulfonic acid group (including a sulfonic acid salt group) regulated so that the content of a sulfonic acid group-containing unit may be 0.5-50 mol% based on 100 mol% whole constituent units, with the water-containing soil, and (B) adding (b) a sulfate containing a divalent or a polyvalent cation capable of forming a hydrate of tri- or more-hydrated product and (c) a hydraulic material to the resultant mixture. The agent for treating the water-containing soil usable for the method for granulating the water-containing soil contains (a) the water-soluble polymer containing the carboxy group (including the carboxylic acid salt group) and the sulfonic acid group (including the sulfonic acid salt group) regulated so that the content of the sulfonic acid group-containing unit may be 0.5-50 mol% based on 100 mol% whole constituent units as a constituent element. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a treatment agent and a treatment method for modifying hydrous soil so that it can be reused as a backfill material as an alternative to sand and the like. The treatment agent and treatment method of the present invention can be applied to hydrous soil having a high moisture content and extremely low viscosity.

  Of the soil generated during construction work, the soil generated during excavation work may cause water to flow into the excavation part and be discharged to the outside as sludge. Since such sludge has a high water content, it remains as it is. However, it cannot be transported by ordinary trucks and dump trucks, and naturally it cannot be used as a backfill material. For this reason, it has been performed that the mud can be transported by subjecting it to a dehydration process or a solidification process.

  However, even if dehydration treatment is performed, it is necessary to make further appropriate improvements in order to recycle as described above. In the case of solidification treatment, what should be done with the obtained solidified soil? However, there was a problem that there were not so many places to dispose of solidified soil to match the amount of mud generated.

  From such a point of view, studies have been made on the use of hydrous soil such as mud in the form of a smooth sandy granular material for backfilling. As a granulation method, for example, there is a method in which a carboxyl group-containing water-soluble polymer powder is added and mixed, then lime is added and mixed, and granulated through curing (Patent Document 1). In addition, as a technique for solving the problem that the carboxyl group-containing water-soluble polymer powder is difficult to dissolve in water-containing soil, there is a method of granulating using a water-soluble polymer containing a carboxyl group and a sulfone group (patent document) 2). Furthermore, Patent Document 3 discloses a method in which a copolymer of acrylamide and acrylic acid and sodium alginate are mixed with mud and granulated. In addition, Patent Document 4 discloses a method for modifying excavated soil containing a water-soluble polymer substance and salts containing divalent or higher cation and hydraulic cement.

Each of the above prior arts has its own characteristics and exhibits its effect, but it may not be said that it has sufficient treatment performance to apply to mud with a high water content ratio and low viscosity, For example, a large amount of a treatment agent such as the water-soluble polymer described above is often required.
JP-A-6-17052 JP 2000-136383 A Japanese Patent Laid-Open No. 10-152682 Japanese Patent Publication No. 4-15038

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a granulated method for hydrous soil that can be formed in a small amount in a short time even in a hydrous soil having a high water content, and a fine granular soil in a short time. It is providing the hydrous soil-treatment agent used for a method.

  The granulated method of hydrous soil of the present invention that can achieve the above-mentioned object includes (A) a carboxyl group (including a carboxylate group) and a sulfone group (including a sulfonate group, the same shall apply hereinafter), and After mixing the water-soluble polymer (a) having a sulfone group-containing unit of 0.5 to 50 mol% in 100 mol% of all the structural units into the water-containing soil, (B) a hydrated product of trihydrate or higher can be formed. It is characterized in that a sulfate (b) containing a cation higher than the valence and a hydraulic substance (c) are added.

  The hydraulic substance (c) is preferably cement, and the divalent or higher cation is preferably one or more of aluminum, iron and magnesium.

  The granulation method of the hydrous soil of the present invention has a gist where the hydrous soil treatment agent of the present invention is mixed with the hydrous soil. The hydrous soil treatment agent of the present invention used in the above method contains a carboxyl group (including a carboxylate group) and a sulfone group (including a sulfonate group), and the sulfone group-containing unit in 100 mol% of all the constituent units. The main point is that the water-soluble polymer (a) is 0.5 to 50 mol% as a constituent element.

Hereinafter, in the present specification, the “carboxyl group” in the water-soluble polymer (a) and the monomer for forming the polymer is a free carboxyl group (—COOH group) unless otherwise specified. In addition, a carboxylate group is also included, and the “sulfone group” includes a sulfonate group in addition to a free sulfone group (—SO ₃ H group) unless otherwise specified.

  Thus, the granulated method for hydrous soil of the present invention is a method for producing granular soil from hydrous soil, and the granular soil obtained by these granulated methods is also included in the present invention.

  The water-containing soil treatment agent of the present invention using a specific water-soluble polymer, a specific sulfate and a hydraulic substance as essential components has excellent water-containing soil treatment performance and is a soil with a high water content. However, it is possible to obtain a granular soil that can be used as a substitute for sand, for example, in a short time with a small amount of use.

  Further, according to the granulated method of the hydrous soil of the present invention using the hydrous soil treatment agent, the hydrous soil that is usually discarded as sludge can be reused, so that environmental conservation, resource saving, and the life of the disposal site can be extended. In addition, it is possible to reduce the disposal cost of hydrous soil.

  Furthermore, the granular soil obtained by the treatment agent and the granulation method of the present invention can be transported by truck, and can be reused for various purposes such as a backfill material as a substitute for sand.

  In this technical field, for example, as disclosed in Patent Document 4 described above, it is known that salts containing a divalent or higher cation can be used together with a water-soluble polymer as a component of a hydrous soil treatment agent. ing.

  However, the present inventors cannot granulate with a conventional hydrous soil treatment agent if a specific sulfate and hydraulic substance are used in a predetermined order together with a specific water-soluble polymer and a hydrous soil treatment agent. It has been found that even a water-containing soil with a high water content and low viscosity can be granulated in a very small amount and in a short time, and the diameter of the granular soil after treatment can be made fine, and the present invention has been completed. It was.

  That is, the water-containing soil treatment method of the present invention includes a water-soluble polymer (a) containing a carboxyl group and a sulfone group, and having a sulfone group-containing unit of 0.5 to 50 mol% in 100 mol% of all constituent units. After mixing with water-containing soil, the greatest feature is the addition of a sulfate (b) containing a divalent or higher cation capable of forming a hydrate more than trihydrate and a hydraulic substance (c). Have.

  The granulation method of the hydrous soil and the mechanism of the hydrous soil treatment by the hydrous soil treatment agent of the present invention are considered as follows.

[1] Granulation effect by water-soluble polymer (a) When the water-soluble polymer (a) is added to and mixed with water-containing soil, the water-soluble polymer (a) is combined with water while being dissolved in water. In addition, water in the system is taken in, the water-soluble polymer (a) molecular chains are adsorbed on some soil particles in such a state that the water is contained, and the soil particles are further bonded and bonded to each other. Take water into the polymer-soil particle network and granulate the hydrous soil.

[2] Formation of etrin guide derived from the sulfate (b) and hydraulic substance (c) In the case of soil with a high water content, the water-soluble polymer (a) alone has the ability to bind soil particles. In order to form a weak and stable granulated state, it is necessary to add a large amount of the water-soluble polymer (a). However, using a large amount of the water-soluble polymer (a) is not desirable in terms of cost. Therefore, in the present invention, in addition to the water-soluble polymer (a), the sulfate (b) and the hydraulic substance (c) are used. When these substances are added to the hydrous soil, the sulfate (b) is first dissociated in the system, and the generated sulfate ions (SO ₄ ²⁻ ) are contained in the hydraulic substance (c). generating a tricalcium aluminate (3CaO · _Al 2 _{O 3)} d by reacting with Trinh guide _{(3CaO · Al 2 O 3 ·} 3CaSO 4 · 32H 2 O). The ethrin guide thus produced forms a strong bond between the soil particles and stabilizes the shape of the resulting granular soil. Further, due to the presence of the etrin guide, granulation is possible even if water is contained in the gap between the soil particles. In addition, as shown in the above composition formula, a large amount of combined water is required for the formation of the ethrin guide, and the formation reaction of the ettrin guide itself contributes to the fixation of moisture in the hydrous soil.

[3] Activation effect of water-soluble polymer (a) by cation derived from sulfate (b) Usually, the surface of soil particles is positively or negatively charged. On the other hand, since the water-soluble polymer (a) according to the present invention has a functional group such as a carboxyl group or a sulfone group, the water-soluble polymer (a) adheres to the surface of the positively charged soil particles, Granulation of hydrous soil progresses. On the other hand, cations generated by the dissociation of the sulfate (b) adhere to the negatively charged soil particle surfaces. And since the said water-soluble polymer (a) adheres to a soil particle further through this cation, the number of the water-soluble polymers (a) which participate in a soil particle increases, and a water-soluble polymer (a ) The granulation of the hydrous soil is further promoted compared to the case where it is used alone.

  In the granulation method and the hydrous soil treatment agent of the present invention, the effects of (1) to (3) are combined, and a stable granulated material can be obtained within a short time from hydrous soil having a high water content and low viscosity. Be able to. Below, the component of the hydrous soil treatment agent of this invention is demonstrated in detail first.

  Examples of the carboxyl group-containing monomer that can be used in the synthesis of the water-soluble polymer (a) used in the present invention include (meth) acrylic acid, crotonic acid, vinyl acetic acid, maleic acid, itaconic acid, mesaconic acid, and fumaric acid. Acid, citraconic acid, N- (meth) acryloylaspartic acid, and carboxylates (for example, alkali metal salts and ammonium salts) of these monomers. These polymerizable monomers can be used alone or in combination of two or more. Among the above exemplified monomers, (meth) acrylic acid and its salt are preferable, and (meth) acrylic acid is more preferable.

  Moreover, the water-soluble polymer (a) of the present invention contains not only a carboxyl group derived from the carboxyl group-containing monomer but also a sulfone group. For example, a carboxyl group-containing water-soluble polymer such as poly (meth) acrylic acid has a relatively slow dissolution rate in water, and a water-containing soil treatment using such a water-soluble polymer compares the treatment time of water-containing soil. May be longer. However, even in such a carboxyl group-containing water-soluble polymer, by further introducing a sulfone group or a sulfonate group, the dissolution rate in water becomes very high. Therefore, the water-containing soil treatment agent using the water-soluble polymer (a) which also contains a sulfone group in addition to the carboxyl group enables water-containing soil treatment in a shorter time.

  In the water-soluble polymer (a) according to the present invention, the sulfone group-containing monomer that can be used for introducing a sulfone group is not particularly limited as long as it is a polymerizable monomer having a sulfone group. 2-acrylamido-2-methylpropanesulfonic acid, (meth) allylsulfonic acid, allyloxybenzenesulfonic acid, 2-hydroxy-3- (2-propenyloxy) propanesulfonic acid, isopropenylsulfonic acid, styrenesulfonic acid, vinyl Examples thereof include sulfonic acid, sulfoethyl (meth) acrylate, sulfonated products of isoprene, and sulfonates (alkali metal salts, ammonium salts, and the like) of these monomers. These monomers can be used alone or in combination of two or more. Among the monomers exemplified above, 2-acrylamido-2-methylpropanesulfonic acid, sulfoethyl (meth) acrylate, and salts thereof are preferable, and 2-acrylamido-2-methylpropanesulfonic acid and sulfoethyl (meth) acrylate are preferable. Particularly preferred. Therefore, the water-soluble polymer (a) is obtained by polymerizing a monomer composition containing (meth) acrylic acid and 2-acrylamido-2-methylpropanesulfonic acid and / or sulfoethyl (meth) acrylate. Are most preferred.

  In the formation of the water-soluble polymer (a), other monomers copolymerizable with the above-mentioned carboxyl group-containing monomer or sulfone group-containing monomer may be used. Examples of such other monomers include monoethylenically unsaturated acids such as allyl phosphonic acid, isopropenyl phosphonic acid, vinyl phosphonic acid, and salts thereof; polyethylene glycol (meth) acrylate, methoxy polyethylene glycol ( Esters of polyalkylene glycols and the above carboxyl group-containing monomers such as (meth) acrylate; methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, isobutyl (meth) acrylate, hydroxyethyl (meth) (Meth) acrylic acid esters such as acrylate and hydroxypropyl (meth) acrylate; vinyl esters such as vinyl acetate, vinyl propionate, vinyl pivalate, vinyl benzoate and vinyl cinnamate; methyl vinyl ether, ethyl Alkyl vinyl ethers such as ruvinyl ether; allyl alcohol, methallyl alcohol, 3-methyl-3-buten-1-ol, 3-methyl-2-buten-1-ol, 2-methyl-3-buten-2-ol, etc. Unsaturated vinyl alcohols; aldehyde group-containing vinyl monomers such as acrolein; nitrile group-containing vinyl monomers such as (meth) acrylonitrile; amide monomers such as (meth) acrylamide and Nt-butylacrylamide; Ethyl methacrylate; styrene; ethylene oxide adduct of allyl alcohol; N-vinyl-2-pyrrolidone; N-vinylacetamide; N-vinylformamide: and the like.

  Among the other monomers exemplified above, monoethylenically unsaturated acid; ester of polyalkylene glycol and carboxyl group-containing monomer; (meth) acrylic acid ester; vinyl ester; alkyl vinyl ether; unsaturated alcohol; Gases such as ammonia may be generated during the treatment of hydrous soil such as phosphoethyl methacrylate; styrene; ethylene oxide adduct of allyl alcohol; N-vinyl-2-pyrrolidone; N-vinylacetamide; N-vinylformamide; No monomer is more preferred. These other monomers may use only 1 type as needed and may use 2 or more types together. Among the other monomers exemplified above, methyl (meth) acrylate, hydroxyethyl (meth) acrylate, and N-vinyl-2-pyrrolidone are particularly preferable.

  In the water-soluble polymer (a), the carboxyl group-containing unit is 50 mol% or more, preferably 75 mol% or more, more preferably 80 mol% or more, out of 100 mol% of all the structural units of the water-soluble polymer. It is recommended that it be 5 mol% or less, preferably 99 mol% or less. When the carboxyl group-containing unit amount is below the above range, it may be necessary to increase the amount of the hydrous soil treatment agent used for the hydrous soil. On the other hand, when it exceeds the above range, it becomes easy to be affected by metal ions present in the soil, and the fluctuation range of the usage amount of the hydrous soil treatment agent may become large.

  In the water-soluble polymer (a), the sulfone group-containing unit is 0.5 mol% or more, more preferably 1 mol% or more, and 50 mol% or less, in 100 mol% of all the structural units of the water-soluble polymer. More preferably, it is 25 mol% or less, More preferably, it is 20 mol% or less. If the amount of the sulfone group-containing unit is below the above range, the effect of improving the water dissolution rate of the polymer due to the introduction of the sulfone group may not be sufficiently ensured. On the other hand, when the above range is exceeded, the amount of the carboxyl group-containing unit present in the water-soluble polymer (a) decreases, so that it is necessary to increase the usage amount of the hydrous soil treatment agent for the hydrous soil as described above. become.

  In the present specification, the above-mentioned “structural unit” in the water-soluble polymer (a) means a basic unit constituting the water-soluble polymer (a), and the carboxyl group-containing unit means such a basic unit. Among them, those containing a carboxyl group and the sulfone group-containing unit mean those containing a sulfone group.

  In the water-soluble polymer (a), the preferred molar ratio of the carboxyl group and the sulfone group that can be derived from the preferred range of the carboxyl group-containing unit amount and the sulfone group-containing unit amount is 199: 1 to 1: 1. More preferably, the molar ratio is 99: 1 to 4: 1. In addition, the molar ratio of the carboxyl group and the sulfone group in the water-soluble polymer (a) was, for example, an aqueous solution adjusted to pH = 2 and an aqueous solution adjusted to pH = 10 according to a conventional method. It can be easily measured by performing colloid titration.

  The production method of the water-soluble polymer (a) is not particularly limited. For example, a polymerization method using a polymerization initiator such as a radical polymerization initiator; radiation such as ionizing radiation and electron beam; and electromagnetic waves such as ultraviolet rays. Various conventionally known polymerization methods such as a polymerization method to be irradiated; a polymerization method by heating; and the like, and two or more of these polymerization methods can be used in combination.

  In addition, as the polymerization mode, various conventionally known polymerization modes such as suspension polymerization, solution polymerization, emulsion polymerization, bulk polymerization and the like can be employed, and these may be either batch type or continuous type. I do not care.

  The radical polymerization initiator that can be used when the polymerization method using the above-described polymerization initiator is employed is not particularly limited, and examples thereof include ammonium persulfate, potassium persulfate, hydrogen peroxide, benzoyl peroxide, and t-butyl peroxide. A reducing agent suitably used in a redox system such as sodium bisulfite, sodium metabisulfate, ferrous ammonium sulfate, L-ascorbic acid, triethanolamine; 2,2′-azobis (2, 4-dimethylvaleronitrile), 2,2′-azobis (2-aminopropane) dihydrochloride, 2,2′-azobisisobutyramide dihydrate, 2,2′-azobis [2- (2-imidazoline) -2-yl) propane] dihydrochloride, 4,4'-azobis (4-cyanopentanoic acid) and other azo initiators; 1-hydroxy- Chlorhexyl-phenyl-ketone (trade name “IRGACURE184”), 2-hydroxy-2-methyl-1-phenyl-propan-1-one (trade name “DAROCUR1173”), eutectic mixture of IRGACURE184 and benzophenone (trade name “ IRGACURE500 ”), 2,2-dimethoxy-1,2-diphenylethane-1-one (trade name“ IRGACURE651 ”), bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide (trade name“ IRGACURE819 ”) ) 2-Methyl-1- [4- (methylthio) phenyl] -2-morpholinopropan-1-one (trade name “IRGACURE907”), 2-benzyl-2-dimethylamino-1- (4-morpholino) Phenyl) -butanone-1 (trade name “IRGACURE369”) and IRGACURE651 3: 7 mixture (trade name “IRGACURE1300”), bis (2,6-dimethoxybenzoyl)- , 4,4-Trimethyl-pentylphosphine oxide and IRGACURE184 1: 3 mixture (trade name “IRGACURE1800”), 1: 1 liquid mixture of 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide and DAROCUR1173 (Trade name “DAROCUR4265”), 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide (trade name “DAROCUR TPO”) and other photoinitiators (both “IRGACURE” and “DAROCUR” are -Photoinitiator manufactured by Specialty Chemicals Co., Ltd.); In addition, the usage-amount of a polymerization initiator, the conditions of a polymerization reaction, etc. are not specifically limited, What is necessary is just to determine suitably according to the kind, amount, etc. of a monomer to be used.

  In the water-soluble polymer (a), the weight average molecular weight is not particularly limited, but is, for example, 100,000 or more, more preferably 500,000 or more, still more preferably 1,000,000 or more, and 20 million or less, more preferably 10 million. It is recommended that: If the weight average molecular weight exceeds the above range, the dissolution rate in water may decrease, and the hydrous soil treatment agent containing such a water-soluble polymer as a constituent element increases the viscosity when mixed with hydrous soil. There is a possibility that it will be difficult to uniformly mix both of the effects, and the synthesis of the polymer itself tends to be difficult. On the other hand, when the weight average molecular weight is less than the above range, the hydrous soil treatment using the water-soluble polymer may lower the hydrous soil treatment performance (granulation performance). In general, as a result of studies by the present inventors, the weight-average molecular weight of the water-soluble polymer (a) tends to be superior in water-containing soil treatment performance on the higher molecular weight side even within the above range. It has been found.

  Incidentally, from the viewpoint of handleability of the hydrous soil treatment agent, a suitable viscosity of the aqueous solution of the water-soluble polymer (a) is, for example, preferably 5 to 10,000 mPa · s at 25 ° C. when the concentration is 0.2% by mass. Is 10 to 2000 mPa · s. Therefore, it is also preferable to adjust the weight average molecular weight of the water-soluble polymer (a) so as to achieve such an aqueous solution viscosity.

  As described above, in the water-soluble polymer (a), the carboxyl group contained in these may be present in the form of a free carboxyl group or a carboxylate group, but it contains a free carboxyl group. Is more preferable. Specific examples of the carboxylate group include alkali metal salts such as sodium salts and potassium salts; alkaline earth metal salts such as calcium salts and magnesium salts; ammonium salts; amine salts; It is not necessarily limited to.

  In 100 mol% of the carboxyl groups contained in the water-soluble polymer (a), the ratio of free carboxyl groups is preferably 5 mol% or more, more preferably 20 mol% or more, and 40 mol% or more. Is more preferable, and 60 mol% or more is particularly preferable. When the ratio of the free carboxyl group is below the lower limit, the water-containing soil treatment performance using such a water-soluble polymer may deteriorate the water-containing soil treatment performance. Depending on the nature of the hydrous soil to be treated (eg, hydrous soil discharged in the Kanto region), the ratio of free carboxyl groups is most preferably 100 mol%.

  When the water-soluble polymer (a) has a carboxylate group or a sulfonate group, it contains a carboxylate group or a sulfonate group as a monomer for forming the water-soluble polymer (a). In addition to synthesis using a monomer, a polymer is once synthesized using a monomer having a free carboxyl group or a free sulfone group, and then part or all of these free carboxyl groups or free sulfone groups are mixed. It may be added to form a salt (carboxylate group, sulfonate group). Examples of alkalis that can be used for neutralization include hydroxides and carbonates of alkali metals such as sodium, potassium, and lithium; ammonia; alkylamines such as monomethylamine, diethylamine, trimethylamine, monoethylamine, dimethylamine, and triethylamine; Alkanolamines such as monoethanolamine, diethanolamine, triethanolamine, isopropanolamine and secondary butanolamine can be mentioned, and sodium hydroxide and carbonate are common.

  In addition, the sulfone group in the water-soluble polymer (a) is post-modified from a specific polymer in addition to the group previously possessed by the polymerizable monomer for forming the water-soluble polymer (a). The group introduced by this may be sufficient.

  In introducing the sulfone group by post-modification, the base polymer (polymer for post-modification) includes, for example, the above-exemplified carboxyl group-containing monomer and, if necessary, the above-exemplified sulfone group-containing monomer. And other monomers (in addition to the monomers exemplified above, for example, those having two or more double bonds in the molecule such as butadiene and isoprene) can be obtained by polymerizing by various methods exemplified above. Things can be used. Among such post-modification polymers, poly (meth) acrylic acid is preferred, and polyacrylic acid is more preferred.

  As a post-modification method for introducing a sulfone group into the above-mentioned post-modification polymer, a method of reacting the polymer with a sulfone group-introducing compound described later can be employed. For example, a method in which a carboxyl group contained in a post-modification polymer and a hydroxyl group contained in sodium isethionate (sodium hydroxyethane sulfonate) as a sulfone group-introducing compound are ester-bonded; An amide bond between the carboxyl group to be synthesized and the amino group contained in the sulfone group-introducing compound taurine sodium salt (sodium aminoethanesulfonate); post-modification using fuming sulfuric acid as the sulfone group-introducing compound, etc. A method of sulfonating a polymer for use; a method of adding a sulfone group-introducing compound, sodium bisulfite, to a double bond contained in a post-modification polymer; Absent.

  The sulfone group-introducing compound is not particularly limited as long as it can introduce a sulfone group into the post-modification polymer. Specific examples other than the compounds exemplified above include compounds suitable for ester bond formation such as sodium hydroxymethanesulfonate and sodium hydroxypropanesulfonate; suitable for amide bond formation such as sodium aminomethanesulfonate and aminopropanesulfonic acid. Compound etc. are mentioned.

  The post-modification reaction method and conditions are not particularly limited, and may be appropriately selected according to the sulfone group-introducing compound to be used and the type of the reaction. For example, a method in which a post-modification polymer and a sulfone group-introducing compound are mixed and heated can be employed. Further, the amount of the sulfone group-introducing compound to the post-modification polymer is not particularly limited, and according to the type of the polymer and the compound, a combination thereof, or the like so that the necessary sulfone group amount can be satisfied. What is necessary is just to determine suitably. Moreover, it is also possible to use the water-soluble polymer (a) as a post-modification polymer and to carry out the above-mentioned post-modification for the purpose of increasing the amount of sulfone groups in the water-soluble polymer.

  In the case of quantifying the amount of the sulfone group-containing unit in the water-soluble polymer into which the sulfone group was introduced by post-modification, the basic unit into which the sulfone group was introduced by post-modification was also included in the sulfone group-containing unit. To do.

  When the water-soluble polymer (a) is used in the hydrous soil treatment agent of the present invention, the polymer may be an aqueous solution, an emulsion, or a powder. In addition, depending on the type and molecular weight of the water-soluble polymer (a), the aqueous solution has a very high viscosity, the handleability may be reduced, or the miscibility with the hydrous soil may be reduced during the hydrous soil treatment. Therefore, in the case of such an aqueous solution of the water-soluble polymer (a), it may be necessary to reduce the viscosity by using a large amount of water to reduce the concentration of the aqueous solution. Therefore, in consideration of handleability and mixability with water-containing soil, the water-soluble polymer (a) is preferably dried and pulverized and used as a powder as necessary. In addition, the drying method and grinding | pulverization method of water-soluble polymer (a) are not specifically limited, What is necessary is just to employ | adopt a conventionally well-known method.

  When the water-soluble polymer (a) is used as a powder (particle), the average particle size is preferably 0.01 to 2 mm, and more preferably 0.02 to 1 mm. If the water-soluble polymer (a) has an average particle size in such a range, even if a treatment agent comprising the water-soluble polymer (a) as a constituent element is mixed with hydrous soil, it is difficult to be spoiled and handled. The property is also good.

  The sulfate (b) used in the present invention contains a divalent or higher cation capable of forming a hydrate higher than trihydrate. The treating agent of the present invention generates an ethrin guide in the system by using the sulfate (b) (above [2]), and further activates the action of the water-soluble polymer (a). In (3) above, even if it is water-containing soil with a high water content, the use of a small amount of the water-soluble polymer (a) makes it possible to turn the water-containing soil into fine granular soil within a short time. It is possible.

  Examples of the divalent or higher cation capable of forming a hydrate higher than the trihydrate contained in the sulfate (b) include a cation of a transition metal of Group 2 or 3 to 15 of the Periodic Table, Examples thereof include cations such as magnesium, aluminum, scandium, titanium, vanadium, manganese, iron, cobalt, nickel, copper, zinc, gallium, rhodium, indium, platinum, lanthanum, and neodymium. Among these, the cation is preferably at least one of aluminum, iron, and magnesium. Specifically, the sulfate (b) includes aluminum sulfate, iron (II) sulfate, and iron sulfate. One or more of (III) and magnesium sulfate are preferred.

  The sulfate (b) is preferably added after mixing and dispersing the water-soluble polymer (a) in the water-containing soil (details will be described later).

  In the hydrous soil treatment agent of the present invention, the hydraulic substance (c) is also an essential component. The hydraulic substance (c) solidifies the granular soil and contributes to the improvement of its strength. At the same time, the hydraulic substance (c) is used together with the sulfate (b) as described above, thereby generating an ethrin guide in the hydrous soil. It also has the effect of fixing the moisture in it as the combined water of the ethrin guide. The hydraulic substance (c) is not particularly limited as long as it is a substance that cures in water, and examples thereof include cement, quicklime, slaked lime, gypsum (semihydrate gypsum, anhydrous gypsum), and mixtures thereof. . Among the hydraulic materials exemplified above, cement is preferable. In the granulation method of the present invention using the water-containing soil treatment agent, in a normal mode, the hydraulic substance (c) is added after mixing and dispersing the water-soluble polymer (a) with the water-containing soil. Is preferred. From the viewpoint of workability, shortening of processing time, and promoting granulation in a short time, the sulfate (b) and the hydraulic substance (c) are added simultaneously or mixed with water in a premixed state. It is recommended to add it to the soil.

  Various known cements can be used as the cement. Examples include, but are not limited to, Portland cement such as ordinary Portland cement, early-strength Portland cement, and ultra-early strong Portland cement; blast furnace cement; alumina cement; calcium cement; fly ash cement; Among them, blast furnace cement can be preferably used in that elution of hexavalent chromium, which is a heavy metal, is not substantially observed.

  In addition, in the water-containing soil treatment agent of the present invention, a water-absorbing resin, a water-absorbing fiber substance (cellulose, pulp, recovered waste paper, etc.), talc, bentonite, acid clay, alumina, kaolin, silica, zeolite, perlite, quartz sand, diatomaceous earth, A fly ash etc. can also be made into a component as needed.

  In the form of the hydrous soil treatment agent of the present invention, the water-soluble polymer (a) (powder, aqueous solution, emulsion) is packaged separately from the sulfate (b) and hydraulic substance (c). Is preferred. The sulfate (b) and the hydraulic substance (c) are not particularly limited, and the sulfate (b) and the hydraulic substance (c) are separately packaged, or the sulfate (b ) And the hydraulic substance (c) can be used in any form such as a package in a mixed state.

  In the method for treating hydrous soil of the present invention, even when any of the above forms of hydrous soil treatment agent is used, first, the water-soluble polymer (a) is mixed with the hydrous soil, and then trihydrate or more. It is important to add a sulfate (b) containing a divalent or higher cation capable of forming a hydrate of the above and a hydraulic substance (c). When the sulfate (b) or hydraulic substance (c) is added first, these components act on the water-soluble polymer (a) before the water-soluble polymer (a) acts on the soil particles, The effect of the water-soluble polymer (a) may not be sufficiently exhibited, and the hydrous soil may not be granulated. In addition, if the said water-soluble polymer (a) is the state disperse | distributed in a hydrous soil, the addition method of the said sulfate (b) and hydraulic substance (c) will not be specifically limited, May be simultaneous. From the viewpoint of shortening workability and treatment time, the sulfate (b) and the hydraulic substance (c) are preferably added simultaneously to the hydrous soil.

  The time until the sulfate (b) and the hydraulic substance (c) are added after mixing the water-soluble polymer (a) is not particularly limited, but the water-containing soil and the water-soluble polymer (a) are sufficiently mixed. After that, it is preferable to add the sulfate (b) and the hydraulic substance (c). Depending on the scale of the treatment scale, for example, about 20 to 180 seconds after mixing the water-soluble polymer (a). It is recommended to add the sulfate (b) or hydraulic substance (c) after a while. In addition, the time (total treatment time) from the start of the treatment of the hydrous soil, that is, the mixing of the water-soluble polymer (a) to the hydrous soil until the completion of the hydrous soil treatment is 420 seconds or less. Is desirable.

  The method of mixing the hydrous soil and the water-soluble polymer (a) or the hydrous soil in which the water-soluble polymer (a) is dispersed with the sulfate (b) and the hydraulic substance (c) is not particularly limited. It is preferable to use a mixer capable of stirring and mixing without kneading. For example, an apparatus including a stirring blade having a shape of a rod or a fishhook so that the mixture can be stirred while applying a shearing force is suitable. That is, the stirring blade having a shape that expands in a direction perpendicular to the moving direction of the mixture that moves by stirring and mixing can suppress the coarsening of the particle diameter due to kneading, and can be applied to the stirring blade and the inner wall of the apparatus. This is desirable because it prevents adhesion of the mixture.

  Examples of such an apparatus include a horizontal axis mixer and a vertical axis mixer. As a horizontal axis type mixer, a single axis and a multi-axis paddle type mixer are preferable. As the vertical shaft type mixer, for example, a pan mixer type mixer is preferable, a planetary type mixer is more preferable, and among these planetary type mixers, a soil mixer, a mortar mixer, and an Eirich mixer are particularly preferable.

  A shorter time to granulation is preferable from the viewpoint of work efficiency, and is usually within a few minutes. By stirring, the hydrous soil becomes a smooth sandy granular soil. The particle size of the granular soil is preferably about 0.1 to 100 mm, and more preferably 0.1 to 40 mm.

  In addition, when the water-containing soil is already granulated by mixing the water-soluble polymer (a) or by mixing the water-soluble polymer (a) and the sulfate (b), sulfuric acid is added to the surface of the granular soil. It is desirable that the salt (b) and / or the hydraulic substance (c) be deposited so as to be applied. Alternatively, a part of the hydraulic substance may be taken into the granular soil.

  The amount of the treatment agent used in the treatment of such hydrous soil varies depending on the mode of hydrous treatment (water content ratio, viscosity, type of soil component, etc.). For example, the water-soluble polymer (100 mass parts of hydrous soil) It is recommended that the amount of use of a) be 0.01 parts by mass or more and 5 parts by mass or less, more preferably 1 part by mass or less. Moreover, it is preferable that the usage-amount of the said sulfate (b) is 0.1 mass part or more with respect to 100 mass parts of hydrous soil, More preferably, it is 2 mass parts or more, More preferably, it is 5 mass parts or more. And it is preferable that it is 100 mass parts or less, More preferably, it is 35 mass parts or less. Furthermore, the usage-amount of a hydraulic substance (c) is 1 mass part or more with respect to 100 mass parts of hydrous soil, More preferably, it is 5 mass parts or more, Comprising: It is 35 mass parts or less. It is recommended, and more preferably 20 parts by mass or less. Therefore, what is necessary is just to determine the usage-ratio of each component in the hydrous soil treatment agent of this invention within the range of the said preferable usage-amount of each component with respect to 100 mass parts of hydrous soil. For example, the mixing ratio [(a) :( b) + (c)] of the water-soluble polymer (a), the sulfate (b) and the hydraulic substance (c) is 1: 1 or more by mass ratio. More preferably, it is 1:10 or more, preferably 1: 10000 or less, more preferably 1: 1000 or less. The blending ratio [(b) :( c)] between the sulfate (b) and the hydraulic substance (c) is preferably 1: 0.01 or more, more preferably 1: It is preferably 0.1 or more and preferably 1: 500 or less, more preferably 1:50 or less.

  In water-containing soil, even if the water content ratio is the same, the viscosity varies depending on the component composition of the soil, and the ease of treatment also varies. Taking into account the effects of such differences in component composition and the like, as an index for evaluating characteristics related to the viscosity of hydrous soil, for example, there is a flow value obtained by the measurement method described later, the hydrous soil treatment agent of the present invention and In the treatment method, not only soil with a relatively low water content of a flow value of about 55 mm or more and less than 70 mm, which is a target for conventional treatment agents, but also soil with a high water content or low viscosity of about 70 mm or more and 1000 mm or less. However, it is possible to obtain a granular soil having a particle size of a conventional level with a small amount of use as described above, and it has a very excellent hydrous soil treatment performance.

  The flow value is obtained as follows. When a hollow cylinder having an inner diameter of 55 mm and a height of 55 mm is placed on a table, and the hydrous soil is filled in the cylinder, the diameter of the hydrous soil spread on the table when the cylinder is lifted vertically (major axis and minor axis) ) Is measured in two directions, and this average value is taken as the flow value.

  The granular soil obtained by the treatment agent and the treatment method of the present invention can be transported by truck, and can be reused for various applications such as a backfill material as a substitute for sand.

  Hereinafter, the present invention will be described in detail based on examples. However, the following examples are not intended to limit the present invention, and all modifications made without departing from the spirit of the preceding and following descriptions are included in the technical scope of the present invention. In this example, “part” is based on mass unless otherwise specified.

<Water-soluble polymer>
Water-soluble polymer A
The water-soluble polymer A is a copolymer of acrylic acid: 90 mol% and sodium 2-acrylamido-2-methylpropanesulfonate: 10 mol%, and is synthesized by the following production method.

  In a 5 L stainless steel separable flask (I) equipped with a stirrer, thermometer, reflux condenser, and nitrogen introduction tube, cyclohexane: 1000 g, sorbitan monostearate: 13.5 g were added, and 50 ml / min with stirring. Nitrogen was introduced at a rate and the temperature was raised to 70 ° C.

  In a 2 L separable flask (II) equipped with a stirrer, thermometer, reflux condenser, and nitrogen introduction tube, acrylic acid: 332.5 g, 2-acrylamido-2-methylpropanesulfonic acid: 106.2 g, 48% by mass Aqueous sodium hydroxide solution: 42.8 g and ion exchange water: 391.8 g were added and dissolved by stirring. Further, while continuing stirring, nitrogen was introduced into the solution of the separable flask (II) for 25 minutes (the dissolved oxygen concentration of the solution was 1 mg / L or less), and then 2,2′-azobis [2- (2-imidazoline- 2-yl) propane] dihydrochloride is 0.03% by mass, 4,4′-azobis (4-cyanopentanoic acid) is 0.04% by mass, and sodium hypophosphite monohydrate is 0.01%. Mass% aqueous solution: 126.9 g was added to the solution in the separable flask (II), and nitrogen was further introduced for 5 minutes.

  Thereafter, the contents of the separable flask (II) were fed to the separable flask (I) over 2 hours for polymerization, and aged for 30 minutes. Next, 6.50% by mass of 2,2′-azobis [2- (2-imidazolin-2-yl) propane] dihydrochloride aqueous solution: 5.9 g was added to the separable flask (I), and further aged for 30 minutes. went. Subsequently, dehydration was performed, followed by cooling to 30 ° C. or lower, solid-liquid separation of the contents, and drying to obtain a water-soluble polymer A (white fine particles).

  A 0.2 mass% aqueous solution of this water-soluble polymer was measured with a B-type viscometer using a rotor: No. The viscosity at 25 ° C. measured at 2 and 30 rpm was 115 mPa · s. The degree of neutralization was 10%.

Water-soluble polymer C
As the water-soluble polymer C, sodium polyacrylate having a weight average molecular weight (MW) of 4 to 5 million was used.
<Evaluation soil>
The evaluation soil is a hydrous soil formed by thoroughly mixing Toyoura standard sand: 5 parts, silt: 75 parts, clay: 270 parts, and tap water: 350 parts. About this evaluation soil, the flow value calculated | required by the above-mentioned measuring method was 250 mm.

Experimental example 1
Evaluation soil: 100 parts were charged into a mixer equipped with a beater-type stirring blade, and while stirring at 160 rpm, 0.25 part of water-soluble polymer A was added and stirred for 240 seconds. Thereafter, 5 parts of aluminum sulfate (manufactured by Wako Pure Chemical Industries, Ltd.): 5 parts and Portland cement (manufactured by Taiheiyo Cement Co., Ltd.): 5 parts were added and further stirred for 15 seconds to treat the evaluation soil. The state of the evaluation soil after the treatment was evaluated according to the criteria shown in Table 1. The results are shown in Table 2.

Experimental example 2
The evaluation soil was treated in the same manner as in Experimental Example 1 except that 5 parts of blast furnace cement (type B blast furnace cement, manufactured by Taiheiyo Cement Co., Ltd.) was used instead of Portland cement. The state of the evaluation soil after the treatment was evaluated according to the criteria shown in Table 1. The results are shown in Table 2.

Experimental example 3
The evaluation soil was treated in the same manner as in Experimental Example 1 except that the amount of water-soluble polymer A added was 0.12 part. The state of the evaluation soil after the treatment was evaluated according to the criteria shown in Table 1. The results are shown in Table 2.

Experimental Example 4
Evaluation soil: 100 parts were charged into a mixer equipped with a beater-type stirring blade, and while stirring at 160 rpm, 0.25 part of water-soluble polymer A was added and stirred for 240 seconds. Thereafter, 2 parts of aluminum sulfate and 8 parts of blast furnace cement were added, and the evaluation soil was further treated by stirring for 30 seconds. The state of the evaluation soil after the treatment was evaluated according to the criteria shown in Table 1. The results are shown in Table 2.

Experimental Example 5
The evaluation soil was treated in the same manner as in Experimental Example 1 except that 5 parts of iron (III) sulfate (manufactured by Wako Pure Chemical Industries, Ltd.) was used instead of aluminum sulfate. The state of the evaluation soil after the treatment was evaluated according to the criteria shown in Table 1. The results are shown in Table 2.

Experimental Example 6
Evaluation soil: 100 parts was charged into a mixer equipped with a beater-type stirring blade, and 0.25 parts of water-soluble polymer A was added while stirring at 160 rpm, followed by stirring for 240 seconds. Thereafter, 5 parts of magnesium sulfate (manufactured by Wako Pure Chemical Industries, Ltd.) and 5 parts of Portland cement were added, and the evaluation soil was further treated by stirring for 20 seconds. The state of the evaluation soil after the treatment was evaluated according to the criteria shown in Table 1. The results are shown in Table 2.

Experimental Example 7
Evaluation soil: 100 parts were charged into a mixer equipped with a beater-type stirring blade, and while stirring at 160 rpm, 0.25 part of water-soluble polymer A was added and stirred for 240 seconds. Thereafter, iron sulfate (II) (manufactured by Wako Pure Chemical Industries, Ltd.): 5 parts and Portland cement: 5 parts were added, and the evaluation soil was further treated by stirring for 30 seconds. The state of the evaluation soil after the treatment was evaluated according to the criteria shown in Table 1. The results are shown in Table 2.

Experimental Example 8
Evaluation soil: 100 parts were charged into a mixer equipped with a beater-type stirring blade and stirred at 160 rpm for 240 seconds, then Portland cement: 10 parts were added, and the evaluation soil was treated by stirring for 60 seconds. That is, this experimental example is an example in which neither a water-soluble polymer nor sulfate is used. The state of the evaluation soil after the treatment was evaluated according to the criteria shown in Table 1. The results are shown in Table 3.

Experimental Example 9
Evaluation soil: 100 parts were charged into a mixer equipped with a beater type stirring blade, and while stirring at 160 rpm, 0.25 part of water-soluble polymer A was added and stirred for 240 seconds. Next, Portland cement: 5 parts was added thereto, and the evaluation soil was further treated by stirring for 60 seconds. The state of the evaluation soil after the treatment was evaluated according to the criteria shown in Table 1. The results are shown in Table 3.

Experimental Example 10
The evaluation soil was treated in the same manner as in Experimental Example 9 except that the amount of Portland cement added was 10 parts. The state of the evaluation soil after the treatment was evaluated according to the criteria shown in Table 1. The results are shown in Table 3.

Experimental Example 11
The evaluation soil was treated in the same manner as in Experimental Example 10 except that the stirring time after adding Portland cement was 15 seconds. The state of the evaluation soil after the treatment was evaluated according to the criteria shown in Table 1. The results are shown in Table 3.

Experimental Example 12
Evaluation soil: 100 parts were charged into a mixer equipped with a beater-type stirring blade, and the water-soluble polymer A: 0.25 part and aluminum sulfate: 5 parts were added in advance while stirring at 160 rpm. After stirring for 240 seconds, Portland cement: 5 parts was added, and the evaluation soil was treated by further stirring for 60 seconds. The state of the evaluation soil after the treatment was evaluated according to the criteria shown in Table 1. The results are shown in Table 4.

Experimental Example 13
Evaluation soil: 100 parts was charged into a mixer equipped with a beater-type stirring blade, and 0.25 parts of water-soluble polymer A was added while stirring at 160 rpm, followed by stirring for 240 seconds. Thereafter, 5 parts of aluminum hydroxide and 5 parts of Portland cement were added, and the evaluation soil was treated by stirring for 60 seconds. The state of the evaluation soil after the treatment was evaluated according to the criteria shown in Table 1. The results are shown in Table 4.

Experimental Example 14
Evaluation soil: 100 parts was charged into a mixer equipped with a beater-type stirring blade, and 0.25 parts of water-soluble polymer A was added while stirring at 160 rpm, followed by stirring for 240 seconds. Thereafter, 5 parts of sodium sulfate (manufactured by Wako Pure Chemical Industries, Ltd.) and 5 parts of Portland cement were added, and the evaluation soil was further treated by stirring for 60 seconds. The state of the evaluation soil after the treatment was evaluated according to the criteria shown in Table 1. The results are shown in Table 4.

Experimental Example 15
Evaluation soil: 100 parts were charged into a mixer equipped with a beater-type stirring blade and stirred at 160 rpm for 240 seconds, then 5 parts of aluminum sulfate and Portland cement: 5 parts were added and stirred for 15 seconds. Processed. That is, this experimental example is an example in which a water-soluble polymer is not used. The state of the evaluation soil after the treatment was evaluated according to the criteria shown in Table 1. The results are shown in Table 4.

Experimental Example 16
Evaluation soil: 100 parts were charged into a mixer equipped with a beater-type stirring blade and stirred at 160 rpm for 240 seconds, then 5 parts of aluminum sulfate and Portland cement: 5 parts were added and stirred for 60 seconds. Processed. That is, this experimental example is an example in which a water-soluble polymer is not used. The state of the evaluation soil after the treatment was evaluated according to the criteria shown in Table 1. The results are shown in Table 4.

Experimental Example 17
Evaluation soil: 100 parts were charged into a mixer equipped with a beater-type stirring blade, and while stirring at 160 rpm, 0.25 part of water-soluble polymer C was added and stirred for 240 seconds. Next, 5 parts of aluminum sulfate and 5 parts of Portland cement were added thereto, and the evaluation soil was further treated by stirring for 15 seconds. The state of the evaluation soil after the treatment was evaluated according to the criteria shown in Table 1. The results are shown in Table 4.

Experimental Example 18
Evaluation soil: 100 parts were charged into a mixer equipped with a beater-type stirring blade, and while stirring at 160 rpm, 0.25 part of water-soluble polymer C was added and stirred for 240 seconds. Subsequently, 5 parts of aluminum sulfate and 5 parts of Portland cement were added thereto, and the evaluation soil was further treated by stirring for 60 seconds. The state of the evaluation soil after the treatment was evaluated according to the criteria shown in Table 1. The results are shown in Table 4.

  Those with an evaluation value of 4 or more after treatment in Table 1 are acceptable, those with 3 or less are unacceptable, and those with higher evaluation values are more suitable as backfill materials, embankment materials, horticultural soils as resources such as sand substitutes. Used for. For example, those having evaluation values 4 and 5 have been granulated to such an extent that they can be easily transported by a truck or the like, and can be used as a backfill material depending on the place of application. About the thing of the evaluation values 6-9, it can use suitably as a backfill material, embankment material, and gardening soil.

  In Tables 2 to 4, among the addition methods of sulfate, “mixing” means that a water-soluble polymer and sulfate are mixed in advance and added to the evaluation soil, and “cement mixing” is hydraulic in advance. This means that the substance and the sulfate were mixed, and “post-addition” in the addition method of the hydraulic substance means that the water-soluble polymer is added to the evaluation soil and the treatment time column in the table. It means that the hydraulic substance was added after mixing for the time shown in. The numerical value of “granulated state” means the evaluation value in Table 1.

  From Table 2, in Experimental Examples 1 to 7 using the water-containing soil treatment agent of the present invention containing the water-soluble polymer (a), the sulfate (b) and the hydraulic substance (c), the sulfate (b) is used. Compared to the experimental examples 9 to 11 (Table 3, granulated state: 5 [Experimental example 9], 6 [Experimental example 10], 2 [Experimental example 11]), a very high level ( It can be seen that the water-containing soil is granulated to the granulated state: 7,9). In particular, very high levels of granulation were achieved in Experimental Examples 1, 2, 4, 5, and 7 using aluminum sulfate, iron (II) sulfate, and iron (III) sulfate as the sulfate (b) ( Granulated state: 9). In addition, from Experimental Example 3, by using sulfate (b) as an essential component, even if the amount of water-soluble polymer (a) used is reduced to less than half, it is suitable as a backfill material and embankment material. It can be seen that the water-containing soil can be sufficiently granulated to a certain level (granulated state: 7). Furthermore, also regarding the post-treatment time, when sulfate (b) was used (Experimental Examples 1 to 7: post-treatment time 15 to 30 seconds), when sulfate (b) was not used (Table 3, Experimental Example 9). , 10: post-treatment time 60 seconds), it can be seen that the granulation of the water-containing soil can be realized quickly.

  Tables 3 and 4 show examples lacking essential components of the water-soluble polymer (a) and / or sulfate (b) (Experimental Examples 8 to 18). In Experimental Example 8 in which only the hydraulic substance (c) was used, the hydrous soil was not granulated at all (granulated state: 1). Further, even in Experimental Examples 15 and 16 in which the water-soluble polymer (a) which is an essential constituent element was not used, the hydrous soil was not granulated at all.

  Further, even in Experimental Examples 13 and 14 using the substitute for the sulfate (b), the excellent granulation effect as in the present invention is not obtained. That is, even if it contains aluminum which is a trivalent or higher cation, it is a hydroxide (Experimental Example 13, granulated state: 6, post-treatment time: 60 seconds), or even if it is sulfate. In the case of a cation (Na) having a valence (Experimental Example 14, granulation state: 2, post-treatment time: 60 seconds), both the granulation state and post-treatment time include the sulfate (b) essential in the present invention. It is inferior to any of the used examples (Experimental Examples 1 to 7). That is, in such a case, it is difficult to produce an ethrin guide in the treatment system (Experimental Example 13), and it is difficult to obtain the activation effect of the water-soluble polymer (Experimental Example 14). Regarding the addition timing of the sulfate (b), when the water-soluble polymer (a) and the sulfate (b) were added and mixed simultaneously, no granular soil was obtained (Table 4, Experimental Example 12). , Granulated state: 1) It can be seen that it is necessary to add a sulfate after previously mixing the water-soluble polymer (a) with water-containing soil.

  Experimental Examples 17 and 18 show examples using sodium polyacrylate as the water-soluble polymer C. The water-soluble polymer C is different from the water-soluble polymer (a) according to the present invention in which the granulation performance is improved by improving the solubility and salt resistance in water-containing soil. Since it was difficult to dissolve in the soil and the granulation performance was insufficient, the hydrous soil was not granulated at all using the sulfate (b) and the hydraulic substance (c) (granulation state: 1) .

  From the above results, according to the present invention having the water-soluble polymer (a), the sulfate (b) and the hydraulic substance (c) as essential components, the water-containing soil can be obtained at a very high level within a short time. It can be seen that it can be granulated.

Claims (5)

A method for granulating hydrous soil,
(A) It contains a carboxyl group (including a carboxylate group) and a sulfone group (including a sulfonate group, the same applies hereinafter), and the sulfone group-containing unit is 0.5 to 50 mol% in 100 mol% of all the structural units. After mixing a certain water-soluble polymer (a) with hydrous soil,
(B) Granulation of water-containing soil characterized by adding a sulfate (b) containing a divalent or higher cation capable of forming a hydrate higher than trihydrate and a hydraulic substance (c) Method.   The method for granulating a hydrous soil according to claim 1, wherein the hydraulic substance (c) is cement.   The granulated method for hydrous soil according to claim 1 or 2, wherein the divalent or higher cation is one or more of aluminum, iron and magnesium.   A granular soil obtained by the granulated method of hydrous soil according to any one of claims 1 to 3. A hydrous soil treatment agent used in the granulated method of hydrous soil according to any one of claims 1 to 3,
Water-soluble which contains a carboxyl group (including a carboxylate group) and a sulfone group (including a sulfonate group, the same applies hereinafter), and the sulfone group-containing unit is 0.5 to 50 mol% in 100 mol% of all the constituent units. A hydrous soil treatment agent comprising a polymer (a) as a constituent element.