JP2011125791A - Boron-containing water treatment method and boron-removing agent - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a boron treatment method and a boron-removing agent which are excellent in removability of boron in boron-containing water, can suppress secondary contamination caused by metal ions or the like, are excellent in filterability of a treated liquid, can reduce the usage of a neutralizing agent required for neutralization, do not require additional filtration because of causing no precipitation of crystals or the like after the neutralization, and can reduce the amount of sludge generated during the treatment of boron. <P>SOLUTION: The boron treatment method includes at least a first treatment process for adding either calcium hydroxide or calcium oxide to the boron-containing water to form a first treated liquid and a second treatment process for adding either hydrogen peroxide or a compound which generates hydrogen peroxide when dissolved in water to the first treated liquid to form a second treated liquid. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a method for treating boron-containing water and a boron removing agent for removing boron from boron-containing water such as industrial wastewater.

Industrial wastewater generated from various product manufacturing processes, combustion gas smoke cleaning processes, contaminated soil purification processes, and the like may contain various harmful substances such as boron. Since these harmful substances may adversely affect animals and plants, it is required by law that the wastewater is discharged into public waters such as rivers, lakes and marshes after removing these harmful substances.
Among these, boron compounds represented by boric acid and sodium borate are used in various industrial applications such as glass industry, pharmaceuticals, cosmetics, raw materials such as dyes, soap industry, components of alloys and semiconductor materials, and electroplating. The waste water generated from these production processes and the like contains a boron compound. In addition, boron compounds are often contained in wastewater generated from power plants, smoke washing wastewater in garbage incineration plants, landfill disposal site leachate wastewater, and the like. Boron compounds may also be contained in the wastewater of the hotel business that runs hot springs. Thus, the boron compound is contained in various wastewaters. Furthermore, when the chelate resin used for removing boron is regenerated with an acid such as sulfuric acid or hydrochloric acid, a waste liquid containing a high concentration of boron may be generated.
On the other hand, boron compounds are essential trace elements for animals and plants. However, excessive intake may cause plant growth inhibition, animal reproductive inhibition toxicity, and nerve / digestive system disorders. Therefore, a part of the Enforcement Ordinance for Water Pollution Prevention Law was revised in 2001, and the drainage standard for boron and its compounds in the sea area is 230 mg / L. The drainage standard for boron and its compounds in public water areas other than sea areas such as rivers and lakes Is defined as 10 mg / L or less.

In general, as a method for removing boron from water containing boron (hazardous substance), an aggregation precipitation method, an ion adsorption method, a solvent extraction method, an evaporation concentration method, a reverse osmosis membrane method, and the like are known.
However, according to the coagulation sedimentation method, it is necessary to use a large amount of chemicals in order to sufficiently remove boron, and there is a problem that the amount of chemicals used is increased and the amount of sludge generated due to processing is increased. There is also a problem that the removal rate decreases when chloride ions coexist in the waste water.
In the ion adsorption method, when wastewater containing a relatively high concentration of boron is treated, the resin used is burdened and inefficient, and not only the cost of the resin itself but also the cost of regeneration treatment is said to be high. There's a problem.
According to the solvent extraction method, since the organic solvent as the extractant is dissolved in the treated water from which boron has been removed, it is necessary to remove the organic solvent, and there is a problem that the cost is increased due to the loss of chemicals.
According to the evaporation concentration method, a heat source is required for evaporation, so enormous energy is required to crystallize the boron compound, and the reverse osmosis membrane method has a low boron removal rate, and there is a problem of membrane clogging. is there.

In order to solve these problems, a method of treating boron-containing water by combining an aggregation precipitation method using an aluminum compound and a calcium compound and an ion adsorption method using an anion exchange resin has been proposed (Patent Document 1). 2).
However, even when these methods are used, it is still necessary to add a large amount of chemicals, the amount of generated sludge is large, and the treatment is difficult.
Further, a method for treating boron-containing water by combining the evaporation concentration method and the coagulation precipitation method (see Patent Document 3), and a method for treating the boron-containing water by combining the evaporation concentration method, the aggregation precipitation method, and the ion adsorption method. (See Patent Document 4) has also been proposed.
However, even with these methods, there is a problem that a large amount of heat is required for evaporation, the apparatus becomes large-scale, the processing steps become complicated, and the cost increases.
In addition, a hazardous substance immobilization material that removes fluorine in waste liquid and phosphate ions in sludge has been proposed (see Patent Document 5). Is not known.
Further, a wastewater treatment method (see Patent Document 6) for adjusting pH by adding aluminum salt, hardly soluble calcium salt, and slaked lime to wastewater containing boron, and boron-containing water in combination with an alkaline earth metal and an aluminum salt. Has also been proposed (see Patent Document 7), but a combination of calcium aluminate hydrate and poorly soluble calcium salt produced in water has a problem that sufficient boron removal power cannot be obtained. .
In addition, when a highly water-soluble barium salt or the like is used, there is a problem that secondary contamination is unavoidable, for example, high-concentration barium is mixed in the solution after boron treatment. That is, there is a problem that if barium chloride is mixed into the solution or sludge after treatment, it cannot be easily removed or decomposed and further contamination occurs.
In addition, since the crystals of barium compounds containing boron are very fine, when a commonly used filter and a slightly finer filter are used, the crystal easily passes through the filter, and a finer filter is used. In this case, there is a problem that clogging occurs immediately and filterability is poor.
Furthermore, the solution treated with these treating agents shows alkalinity or acidity, and it is necessary to neutralize with a neutralizing agent. However, if the alkalinity or acidity is strong, neutralization necessary for neutralization is required. There is a problem that a large amount of the agent must be used, and in addition to the reduction in processing efficiency, the cost increases.
Moreover, since a crystal | crystallization will precipitate when a processing solution is neutralized after performing a boron treatment and filtration, there also exists a problem that it is necessary to filter again. If the solution is neutralized with a neutralizing agent after the boron treatment, the boron is redissolved in the treatment solution from the removal agent insoluble in water containing boron. There is a need to do.
Therefore, boron removal in boron-containing water is excellent, secondary contamination such as metal ions can be suppressed, filterability of the treatment liquid is excellent, the amount of neutralizing agent used for neutralization can be suppressed, Since there is no precipitation of crystals and the like after neutralization, there is a need for a boron treatment method and a boron remover that can reduce the amount of sludge generated during boron treatment without the need for re-filtration. Is the current situation.

JP-A-57-81881 JP-A-57-180493 JP 7-323292 A Japanese Patent Laid-Open No. 10-314798 JP 2000-93927 A JP 2004-283731 A JP 2005-262186 A

  An object of the present invention is to solve the conventional problems and achieve the following objects. In other words, it has excellent boron removability in boron-containing water, can suppress secondary contamination such as metal ions, is excellent in filterability of the treatment liquid, can suppress the amount of neutralizing agent used for neutralization, An object of the present invention is to provide a boron treatment method and a boron remover that can reduce the amount of sludge generated during boron treatment because there is no precipitation of crystals and the like even after neutralization, and in addition, no filtration is required. .

The present invention provides the following means for solving the problems. That is,
<1> A first treatment step in which either calcium hydroxide or calcium oxide is added to boron-containing water to form a first treatment liquid, and hydrogen peroxide and water are added to the first treatment liquid. A treatment method for boron-containing water, comprising at least a second treatment step in which any one compound that generates hydrogen peroxide by being dissolved in the solution is added to obtain a second treatment solution.
<2> The method for treating boron-containing water according to <1>, further including a pH adjustment step of adjusting the pH of the boron-containing water to 9.5 or less.
<3> The method for treating boron-containing water according to any one of <1> to <2>, further comprising a coagulation step of adding a polymer flocculant to the second treatment liquid to obtain an aggregate containing boron. It is.
<4> The method for treating boron-containing water according to any one of <1> to <3>, wherein an initial concentration of boron in the boron-containing water is 200 mg / L or more.
<5> The boron-containing water according to any one of <1> to <4>, wherein the molar concentration of calcium hydroxide and calcium oxide added to any boron-containing water is 0.67 mmol% to 121 mmol%. It is a processing method.
<6> The above <1> to <5, wherein the molar concentration of hydrogen peroxide and any compound that generates hydrogen peroxide by dissolving in water with respect to boron-containing water is 1.5 mmol% to 180 mmol% > The method for treating boron-containing water according to any one of the above.
<7> The initial concentration of boron in boron-containing water is 600 mg / L to 1,500 mg / L, and any one of calcium hydroxide and calcium oxide is used as component A, dissolved in hydrogen peroxide and water, and hydrogen peroxide. Any one of <1> to <6>, wherein A / B, which is a molar ratio of the A component to the B component, is 0.15 to 1.50 A method for treating boron-containing water according to claim 1.
<8> A first treatment step in which either calcium hydroxide or calcium oxide is added to boron-containing water to form a first treatment liquid, and hydrogen peroxide and water are added to the first treatment liquid. A second treatment step of adding any one of the compounds that generate hydrogen peroxide by dissolving in water into a second treatment liquid. A is a molar ratio of the A component to the B component when any one of calcium oxide is used as the A component and any one compound that dissolves in the hydrogen oxide and water to generate hydrogen peroxide is used as the B component. / B is a boron removing agent characterized by 0.10 to 6.00.

  According to the present invention, the conventional problems can be solved, the object can be achieved, boron removal in boron-containing water is excellent, and secondary contamination such as metal ions can be suppressed. , Excellent filterability of treatment liquid, can reduce the amount of neutralizing agent used for neutralization, and there is no precipitation of crystals after neutralization. It is possible to provide a boron treatment method and a boron remover that can reduce the amount of generated sludge.

(Method of treating boron-containing water)
The method for treating boron-containing water of the present invention includes at least a first treatment step and a second treatment step, and includes other steps as necessary.

<First treatment process>
The first treatment step is a step of adding a component A selected from either calcium hydroxide or calcium oxide to the boron-containing water to obtain a first treatment liquid.

The initial concentration of boron in the boron-containing water is not particularly limited and may be appropriately selected depending on the purpose. The treatment method of the boron-containing water is a boron concentration from a low concentration to a high concentration (for example, 9,000 mg). High boron removability can be expected with respect to the boron-containing water contained in / L).
Among these, the lower limit of the initial concentration of boron in the boron-containing water is preferably 200 mg / L or more, more preferably 300 mg / L or more, and particularly preferably 600 mg / L or more.
If it is less than 200 mg / L, boron may not be efficiently removed.

  The component A is not particularly limited as long as it is selected from either calcium hydroxide or calcium oxide. For example, a commercially available product can be used.

There is no restriction | limiting in particular as addition molar concentration with respect to the said boron containing water of the said A component (concentration in the said boron containing water), Although it can select suitably according to the objective, 0.67 mmol%-121 mmol% are It is preferably 4.9 mmol% to 121 mmol%, more preferably 4.9 mmol% to 60 mmol%.
If the added molar concentration of the component A is less than 0.67 mmol%, the boron removing power may be insufficient. If it exceeds 121 mmol%, a large amount of sludge is generated, and the load of the filtration process is reduced. May grow.

There is no restriction | limiting in particular as an addition processing method of the said A component, It does not need to be stirred and when stirring, an apparatus, operation, etc. are not restrict | limited in particular, A conventionally well-known apparatus and operation can be used. .
Although there is no restriction | limiting in particular as addition time of the said A component, For example, 0.5 to 600 minutes are preferable.

<Second treatment process>
In the second treatment step, a component B selected from hydrogen peroxide and a compound that generates hydrogen peroxide by being dissolved in water is added to the first treatment liquid to add a second treatment. As a step of making a liquid.
Even if the addition order of the A component and the B component is reversed or the A component and the B component are added simultaneously, the boron-containing water treatment method cannot obtain a high boron removal power. Regarding the addition of the component and the B component, the second processing step is performed after the first processing step as an important core of the technology. Here, “after the first treatment step” indicates a state in which the A component has been added to the boron-containing water.

  The component B is not particularly limited as long as it is at least one of hydrogen peroxide and a compound that generates hydrogen peroxide by dissolving in water, and a commercially available product can be used for the water. Examples of the compound that generates hydrogen peroxide when dissolved include percarbonate. These may be used alone or in combination of two or more.

There is no restriction | limiting in particular as addition molar concentration (concentration in the said boron containing water) of the said B component with respect to the said boron containing water, Although it can select suitably according to the objective, 1.5 millimol%-180 millimol% are Preferably, 5.3 to 180 mmol% is more preferable, and 5.3 to 90 mmol% is particularly preferable.
If the added molar concentration of the component B is less than 1.5 mmol%, the boron removing power may be insufficient, and if it exceeds 180 mmol%, no significant improvement in boron removing power can be expected. There is.

The B component addition treatment method is not particularly limited and may or may not be stirred. When stirring, the apparatus and operation are not particularly limited, and conventionally known apparatuses and operations can be used. .
The B component addition treatment time is not particularly limited, but is preferably 0.5 minutes to 600 minutes, for example.

<A component/B component>
The A component used in the first treatment step and the second treatment step is either calcium hydroxide or calcium oxide, and the B component is dissolved in hydrogen peroxide and water to generate hydrogen peroxide. It is very important to be one of the compounds.
Even if the A component is used as a barium compound, a sodium compound, other calcium compounds (for example, calcium chloride, calcium carbonate, calcium sulfate) or the like, a high boron removal rate cannot be obtained, and the B component is used as another oxidizing agent (for example, excess A high boron removal rate cannot be obtained as a peroxide such as sodium oxide or sodium hypochlorite. Further, even if calcium peroxide that can be synthesized with the A component and the B component is used, a high boron removing power cannot be obtained. Although the reason for such a result is not clear, a high boron removal rate can be obtained for the first time in the combination of the A component and the B component.
In addition, in the combination of the A component and the B component (hereinafter sometimes referred to as boron removing agent), secondary contamination by metal ions such as barium chloride can be suppressed, and the filterability of the treatment liquid is excellent. The amount of neutralizing agent used for neutralization can be reduced, and a synergistic effect is obtained that there is no turbidity due to precipitation of crystals after neutralization and there is no need to perform filtration again. A treatment process for removing boron from boron-containing water such as good industrial wastewater can be provided.

Although there is no restriction | limiting in particular as said A component and said B component, expression of effects, such as higher boron removal property, can be anticipated by selecting a compounding ratio suitably.
Here, according to the study by the present inventors, further knowledge about an appropriate blending ratio of the A component and the B component has been obtained according to the initial concentration of boron in the boron-containing water.
That is, when the initial concentration of boron is 200 mg / L or more and 300 mg / L or less, the A / B which is the molar ratio of the A component and the B component is preferably 0.10 to 0.50, -0.20 is more preferable.
When the initial concentration of boron is greater than 300 mg / L and 600 mg / L or less, the A / B, which is the molar ratio of the A component and the B component, is preferably 0.15 to 1.00, 0.17 to 0.80 is more preferable, and 0.30 to 0.50 is particularly preferable.
When the initial concentration of boron is greater than 600 mg / L and 1,000 mg / L or less, the A / B, which is the molar ratio of the A component and the B component, is preferably 0.15 to 1.50. 17 to 1.20 is more preferable, and 0.30 to 1.00 is particularly preferable.
When the initial concentration of boron is greater than 1,000 mg / L and less than or equal to 1,500 mg / L, A / B that is the molar ratio of the A component and the B component is preferably 0.17 to 1.50, 0.30 to 1.20 is more preferable, and 0.35 to 1.20 is particularly preferable.
When the initial concentration of boron is greater than 1,500 mg / L and less than or equal to 2,000 mg / L, the A / B that is the molar ratio of the A component and the B component is preferably 0.20 to 2.00, 0.30 to 2.00 is more preferable, and 0.50 to 1.50 is particularly preferable.
When the initial concentration of boron is greater than 2,000 mg / L and less than or equal to 2,500 mg / L, the A / B that is the molar ratio of the A component and the B component is preferably 0.35 to 6.00, 0.40 to 6.00 is more preferable, and 0.50 to 3.00 is particularly preferable.
When the initial concentration of boron is greater than 2,500 mg / L and less than or equal to 3,000 mg / L, the A / B that is the molar ratio of the A component and the B component is preferably 0.50 to 6.00, 0.60 to 6.00 is more preferable, and 0.80 to 3.00 is particularly preferable.
When the initial concentration of boron is greater than 3,000 mg / L and less than or equal to 3,500 mg / L, the A / B that is the molar ratio of the A component and the B component is preferably 0.80 to 6.00, 1.30 to 6.00 is more preferable, and 1.50 to 3.00 is particularly preferable.

<Other processes>
There is no restriction | limiting in particular as said other process, According to the objective, it can select suitably, For example, a pH adjustment process, an aggregation process, and a post-processing process as needed are mentioned.

The pH adjustment step is a step of adjusting the pH of the boron-containing water.
The pH adjustment step is not particularly limited, but is preferably a step of adding a pH adjuster to the boron-containing water used in the first treatment step and adjusting the pH in advance. .
The pH to be adjusted is not particularly limited, but is preferably 9.5 or less, more preferably 8.9 or less, and particularly preferably 8.4 or less.
When the pH exceeds 9.5, a high boron removal rate may not be obtained.
The pH is preferably 1 or more.
The pH adjuster is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include general acids such as sulfuric acid, nitric acid and hydrochloric acid, and general acids such as sodium hydroxide and potassium hydroxide. And an alkaline agent.

The aggregation step is a step of adding a polymer flocculant to the second treatment liquid to obtain an aggregate containing boron. When the agglomeration step is included, after the boron treatment, water having a sufficiently low boron concentration and the boron treatment agent containing the component A and the component B can be easily separated.
The agglomeration step is not particularly limited, but after the second treatment step, the polymer flocculant is further added to the liquid after treatment, and after the treatment with the boron remover containing removed boron. It is preferable to be a step of solid-liquid separation of the water.
The polymer flocculant is not particularly limited and can be appropriately selected depending on the purpose. For example, an anionic polymer flocculant, a nonionic polymer flocculant, a cationic polymer flocculant, an amphoteric polymer flocculant Examples thereof include a molecular flocculant. Among these, as the polymer flocculant, an anionic polymer flocculant, a cationic polymer flocculant, and an amphoteric polymer flocculant are preferable. These may be used alone or in combination of two or more.
There is no restriction | limiting in particular as addition amount of the said polymer flocculant, Although it can select suitably according to the objective, For example, 0.00005 mass%-1 mass with respect to the boron containing water amount made into the process target % Is preferable, and 0.0001 mass% to 0.5 mass% is more preferable.
When the amount used is within the preferable range, it is advantageous in that the coagulability of the boron removing agent can be further increased and solid-liquid separation can be performed efficiently.

The solid-liquid separation is not particularly limited, and can be carried out using a normal apparatus by means such as decantation, filtration, and centrifugation.
By performing the solid-liquid separation, the boron removing agent after the boron treatment can be easily recovered. The recovered boron removing agent is, for example, boron-containing water again after performing an appropriate treatment. Can be used for removal. Specifically, by drying or heat-treating a substance insoluble in water (boron removal agent) recovered after the boron treatment, the obtained processed product can be used again for removing boron containing boron-containing water. it can. Moreover, the slurry solution containing the boron removal agent collect | recovered after a boron process can also be used for the boron removal of boron containing water again. The heat-treated product or slurry solution can be suitably reused for removing boron-containing water until the saturated boron adsorption amount is reached.

  There is no restriction | limiting in particular as said post-processing process, According to the objective, it can select suitably, For example, adding a neutralizing agent with respect to a 2nd processing liquid, obtaining the processing liquid neutralized Examples of the summing step and the second treatment liquid include a filtration step of performing filtration to obtain a treatment liquid.

There is no restriction | limiting in particular as said neutralizing agent, According to the objective, it can select suitably, For example, a sulfuric acid, sodium hydroxide, etc. are mentioned.
Moreover, there is no restriction | limiting in particular as said filtration method, According to the objective, it can select suitably, For example, the method of filtering using a well-known filtration filter is mentioned.

(Boron remover)
The boron removing agent of the present invention is used in the method for treating boron-containing water of the present invention, and A / B, which is the molar ratio of the component A and the component B, is 0.10 to 6.00. Become.
According to the boron removing agent, a high boron removal rate can be obtained particularly for boron-containing water having an initial boron concentration of 600 mg / L to 1,500 mg / L.
The initial concentration of boron is 200 mg / L to 300 mg / L, greater than 300 mg / L to 600 mg / L, greater than 600 mg / L to 1,000 mg / L, greater than 1,000 mg / L to 1,500 mg / L. Hereinafter, greater than 1,500 mg / L and less than or equal to 2,000 mg / L, greater than 2,000 mg / L and less than or equal to 2500 mg / L, greater than 2,500 mg / L and less than or equal to 3,000 mg / L, and 3,000 mg / L In each case of greater than or equal to 3,500 mg / L, a boron removal agent having a numerical value range of A / B corresponding to the initial concentration of boron described for the method for treating boron-containing water of the present invention, Provided.

There is no restriction | limiting in particular as long as the dosage form of the said boron removal agent contains the said A component and the said B component, Each is contained in aspects, such as a lump shape, a granular form, a powder form, and a liquid form.
About matters other than this, all the matters described in the said boron containing water of this invention can be applied suitably.

  EXAMPLES Hereinafter, although an Example and a comparative example are given and this invention is demonstrated in detail, this invention is not limited to these Examples at all.

(Examples 1 to 11)
A 125 mL mayonnaise bottle was charged with 100 g of boron solution (initial boron concentration 1,000 mg / L, prepared using boric acid, pH 5.2) and a stir bar, and stirred at 350 rpm. A predetermined amount of calcium compound (calcium hydroxide or calcium oxide) is added here (first treatment step), and after stirring for 5 minutes, a predetermined amount of 30 mass% hydrogen peroxide solution is added (second treatment). Step), and further stirred for 1 hour to treat the boron-containing water in Examples 1-11.
Here, the calcium compound and its addition amount (addition concentration in the boron solution) and the addition amount of hydrogen peroxide water (addition concentration in the boron solution) were the conditions shown in Tables 1-1 and 1-2 below. .

(Examples 12 to 16)
In Example 6, the boron-containing water treatment in Example 12 was performed in the same manner as in Example 6 except that the pH of the boron solution was changed from 5.2 to 2.0 using sulfuric acid.
Further, in Example 6, boron in Examples 13 to 15 was used in the same manner as in Example 6 except that the pH of the boron solution was changed to a predetermined pH using sodium hydroxide and the sodium concentration was changed. Treatment of the contained water was performed.
Here, the concentration of sodium and the pH of the boron solution were the conditions shown in Table 2 below.
Further, in Example 4, the pH of the boron solution was changed from 5.2 to 9.4 using sodium hydroxide, and the sodium concentration was changed from 0 mg / L to 1,020 mg / L. In the same manner as above, the treatment of boron-containing water in Example 16 was performed.

(Examples 17 to 25)
In Example 1, the boron concentration of the boron solution was changed to a predetermined concentration and a predetermined pH, and the addition concentration of the calcium compound and hydrogen peroxide was changed to a predetermined amount. Treatment of boron-containing water at 25 was performed.
Here, the boron concentration of the boron solution, pH, and the addition concentration of the calcium compound and hydrogen peroxide were the conditions shown in Tables 3-1 and 3-2 below.

(Example 26 and Example 27)
In Example 1, the boron-containing water treatment in Examples 26 and 27 was performed in the same manner as in Example 1 except that the addition amounts of the calcium compound and hydrogen peroxide to the boron solution were changed to predetermined amounts. It was.
Here, the calcium compound (addition concentration in the boron solution) and the addition amount of hydrogen peroxide (addition concentration in the boron solution) were the conditions shown in Table 4 below.

(Examples 28 to 32)
A 500 mL beaker was charged with 400 g of a boron solution (boron concentration 1,020 mg / L, prepared using boric acid, pH 5.1), and set in a jar tester (MJS-2) manufactured by Miyamoto Seisakusho. While stirring at 200 rpm, 2.88 g of calcium hydroxide was added (first treatment step) and stirred for 5 minutes. Thereafter, 6.40 g of 30 mass% hydrogen peroxide water was added (second treatment step), and the mixture was stirred for 1 hour. Thereafter, 15.0 g of a 0.1% by weight aqueous solution of a predetermined polymer material was added and stirred for 5 minutes to treat the boron-containing water in Examples 28-32.
Here, the conditions shown in Table 5 below were set for the polymer flocculant-containing aqueous solution.

(Comparative Examples 1-3)
A 125 mL mayonnaise bottle was charged with 100 g of a boron solution (initial boron concentration 1,000 mg / L, prepared using boric acid, pH 5.2) and a stir bar, and stirred at 350 rpm. A predetermined amount of calcium compound or 30% by mass hydrogen peroxide solution was added thereto, and the mixture was stirred for 1 hour to treat the boron-containing water in Comparative Examples 1 to 3.
Here, the calcium compound, the addition amount thereof, and the addition amount of hydrogen peroxide water were set to the conditions shown in Table 6 below.

(Comparative Examples 4 to 14)
A 125 mL mayonnaise bottle was charged with 100 g of a boron solution (initial boron concentration 1,000 mg / L, prepared using boric acid, pH 5.2) and a stir bar, and stirred at 350 rpm. A predetermined amount of an alkali compound, calcium compound, and barium compound was added thereto, and the mixture was stirred for 5 minutes. Then, a predetermined amount of 30% by mass hydrogen peroxide or an oxidizing agent was added, and the mixture was further stirred for 1 hour. Comparative Example 4 Treatment of boron treated water at ˜13 was performed.
A 125 mL mayonnaise bottle was charged with 100 g of a boron solution (initial boron concentration 1,000 mg / L, prepared using boric acid, pH 5.2) and a stir bar, and stirred at 350 rpm. A predetermined amount of calcium peroxide was added thereto, and the mixture was stirred for 1 hour, and treated with boron-treated water in Comparative Example 14.
Here, alkali compound and its addition amount (addition concentration in the boron solution), calcium compound addition amount (addition concentration in the boron solution), barium compound and addition amount (addition concentration in the boron solution), hydrogen peroxide Regarding the addition amount of water (addition concentration in the boron solution), the oxidizing agent and its addition amount (addition concentration in the boron solution), and the combination of additions, the conditions shown in Tables 7-1 and 7-2 below were used. .

(Comparative Example 15)
The boron-containing water in Comparative Example 15 was treated with reference to the method described in JP-A-2007-283216. Specifically, in a 125 mL mayonnaise bottle, 100 g of a boron solution (boron concentration 1,000 mg / L, prepared using boric acid, sodium concentration 0 mg / L, barium concentration 0 mg / L, pH 5.2) and a stir bar are placed. And stirred at 350 rpm. 30 mass% hydrogen peroxide solution 0.93g was added here, and it stirred for 30 minutes. Subsequently, 0.39 g of barium chloride dihydrate was added and stirred for 5 minutes, and then 2.77 g of 5 mol / L sodium hydroxide was added to adjust the pH to 11.5. Thereafter, the mixture was stirred for 1 hour and treated with boron-containing water in Comparative Example 15.
Boron concentration after treatment (mg / L) 612
Sodium concentration in treatment liquid (mg / L) 2,280
Barium concentration in treatment liquid (mg / L) 31
Metal concentration increased by treatment (mg / L) 2,311
Turbidity (degree) of filtrate 60
No clogging during filtration ×
0.5 mol / L sulfuric acid solution weight (g) required for pH adjustment 6.1
Solution turbidity (degree) after pH adjustment 43

(Comparative Example 16)
The treatment of boron-containing water in Comparative Example 16 was performed with reference to the method described in Japanese Patent Application Laid-Open No. 2007-283216. Specifically, in Comparative Example 15, the treatment of boron-containing water in Comparative Example 16 was performed in the same manner as Comparative Example 15 except that the order of addition of hydrogen peroxide and barium chloride dihydrate was reversed. went.
Boron concentration after treatment (mg / L) 622
Sodium concentration in treatment liquid (mg / L) 2,220
Barium concentration in treatment liquid (mg / L) 30
Metal concentration increased by treatment (mg / L) 2,250
Turbidity (degree) of filtrate 60
No clogging during filtration ×
0.5 mol / L sulfuric acid solution weight (g) required for pH adjustment 6.2
Solution turbidity (degree) after pH adjustment 38

(Comparative Example 17)
The treatment of boron-containing water in Comparative Example 17 was performed with reference to the method described in JP-A-10-76276. Specifically, boron solution (boron concentration 1,000 mg / L, prepared using boric acid, sodium concentration 0 mg / L, calcium concentration 0 mg / L, aluminum concentration 0 mg / L, pH 5.2) in a 125 mL mayonnaise bottle 100 g and a stirring bar were added and stirred at 350 rpm. After adding 0.0406 g of 87 mass% sodium peroxide and stirring for 30 minutes, 0.671 g of aluminum sulfate 14-18 hydrate (aluminum sulfate = 55.3%) and 0.134 g of calcium hydroxide were added. Further, 2.16 g of 5 mol / L sodium hydroxide solution was added to adjust the pH to 10. Then, the boron containing water in the comparative example 17 was processed by stirring for 1 hour.
Boron concentration after treatment (mg / L) 767
Sodium concentration in treatment liquid (mg / L) 2,010
Calcium concentration in treatment liquid (mg / L) 420
Aluminum concentration in treatment liquid (mg / L) 53
Metal concentration increased by treatment (mg / L) 2,483
Turbidity (degree) of filtrate 0.2
No clogging during filtration ○
0.5 mol / L sulfuric acid solution weight (g) required for pH adjustment 4.5
Solution turbidity (degree) after pH adjustment 20

(Comparative Example 18 and Comparative Example 19)
The boron-containing water in Comparative Example 18 was the same as Example 6 except that the addition order of the calcium compound and the hydrogen peroxide solution was reversed in the first treatment step and the second treatment step of Example 6. (See Table 8 below).
Moreover, in Example 6, it replaced with the 1st process process and the 2nd process process, Example 6 except having added the calcium compound and the hydrogen peroxide solution to the boron solution simultaneously, and performing stirring for 1 hour. Similarly, the treatment of boron-containing water in Comparative Example 19 was performed (see Table 8 below).

(Measurement and evaluation methods for boron removal and secondary contamination)
About 0.5 mL of the solution after treatment of boron-containing water in Examples 1 to 27 and Comparative Examples 1 to 19 was sampled, filtered through a 0.45 μm filter, diluted with a nitric acid solution, and an ICP emission spectrometer (stock) ) Boron concentration and metal ion concentrations of calcium, sodium, potassium, magnesium, aluminum, and barium were measured with an optima5300DV manufactured by PerkinElmer Japan.
The calculation of the boron removal rate was performed by the following formula (1) based on the measurement result.
Boron removal rate (%) = (1−C ₁ / C ₀ ) × 100 (1)
C ₁ : Boron concentration after treatment (mg / L)
C ₀ : Initial boron concentration before treatment (mg / L)
Moreover, evaluation with respect to a boron removal rate is evaluated based on the following evaluation criteria.
Preferred 70% or more More preferred 80% or more Particularly preferred 85% or more *) However, the boron removal rate is closer to 100%, indicating that the boron removal power is higher.

The calculation of the increase in the metal ion concentration was performed according to the following equation.
Metal ion concentration increment = Metal ion concentration after treatment-Metal ion concentration before treatment The evaluation of secondary contamination by the metal ions is as follows from the total (mg / L) of metal ion concentration increased before and after treatment: Based on the evaluation criteria.
(Circle): 1,500 mg / L or less (double-circle): 750 mg / L or less The result regarding the above boron removal power is shown to the following Table 1-1-Table 8. Moreover, the result regarding secondary contamination is shown in the following Table 1-1 to Table 4, Table 6 to Table 8. In addition, Comparative Examples 15 to 17 are as described above.

(Measurement method and evaluation of filterability)
Solutions after treatment of boron-containing water in Examples 1 to 27 and Comparative Examples 1 to 17 After suction filtration using 5C filter paper (for fine filtration, diameter 60 mm), the turbidity of the filtrate was measured using a water analyzer 2000N, Nippon Denshoku Industries Co., Ltd.
Evaluation for filterability is evaluated based on the following evaluation criteria.
Turbidity (degree)
○: 10 degrees or less ◎: 5 or less *) However, the smaller the numerical value, the less the turbidity of the solution.

Moreover, as evaluation regarding filtration, the clogging at the time of filtration was measured and evaluated.
The filtrate used for the measurement of the said filterability was filtered using a 0.45 μm filter (Lab Lab Company Co., Ltd. CA filter, diameter 25 mm) and filtered until the filtrate weight became 75 g. Filtration was performed while gently pressing the syringe with a finger, and the filter was replaced when the filtration rate was clearly reduced and the filter was clogged.
Based on the measurement results regarding the absence of clogging during the filtration, the evaluation was performed according to the following evaluation criteria.
○: Filtration was completed without replacing the filter Δ: One filter was exchanged because clogging was felt ×: Two or more filters were exchanged because clogging was felt -1 to Table 4 and Tables 6 to 8. In addition, Comparative Examples 15 to 17 are as described above.

(Measurement method and evaluation of neutralizing properties)
Regarding the amount of acid required for neutralization, it was necessary to neutralize 75 g of the filtrate (turbidity of 0.1 or less) used in the measurement of the filterability with 0.5 mol / L sulfuric acid to bring the pH to 7. The 5 mol / L sulfuric acid weight was measured.
The amount of acid required for neutralization is evaluated according to the following evaluation criteria from the weight (g) of sulfuric acid (0.5 mol / L) required for pH adjustment.
○: 5.0 g or less ◎: 3.5 or less In addition, neutralization in Comparative Examples 3, 7, 8, 10, and 11 is 1.0 mol / L hydroxylation of 75 g of filtrate (turbidity 0.1 or less). The weight of 1.0 mol / L sodium hydroxide required to neutralize with sodium and bring the pH to 7 was measured.
The amount of alkali necessary for neutralization at this time is evaluated according to the following evaluation criteria from the weight (g) of sodium hydroxide required for pH adjustment (1.0 mol / L).
(Circle): 5.0 g or less (double-circle): 3.5 g or less The result regarding the above neutralization property is shown in the following 1-1-Table 4, and Table 6-Table 8. In addition, Comparative Examples 15 to 17 are as described above.

(Measuring method and evaluation method of cohesiveness)
Regarding the cohesiveness of the solution after the treatment of boron-containing water in Examples 28 to 32, 75 g of the supernatant was sampled and the turbidity was measured.
Here, the evaluation of the cohesiveness is performed according to the following evaluation criteria based on the measurement result of the turbidity.
Turbidity (degree)
○: 10 degrees or less ◎: 5 or less In addition, about 0.5 mL of the treatment solution is sampled, filtered with a 0.45 μm filter, diluted with a nitric acid solution, an ICP emission spectrophotometer manufactured by PerkinElmer Japan Co., Ltd., optima5300DV Used to measure the boron concentration in the solution. The evaluation of the boron removing power is as described above.
The results relating to the above cohesiveness and boron removing power are shown in Table 5 below.

In Table 1-1 to Table 8, various contents of each component used in Examples and Comparative Examples are shown in Table 9 below. In addition, Table 9 below shows Examples and Comparative Examples, and grades and sources of components used for measurement and evaluation.

  The boron-containing water treatment method and boron removal agent of the present invention are particularly useful for boron treatment in various industrial wastewaters, for example, for the purpose of satisfying drainage standards for boron and its compounds.

Claims (8)

A first treatment step of adding either calcium hydroxide or calcium oxide to the boron-containing water to form a first treatment liquid;
A second treatment step of adding a hydrogen peroxide and any compound that generates hydrogen peroxide by dissolving in water to the first treatment liquid to obtain a second treatment liquid;
A process for treating boron-containing water, characterized by comprising at least   The processing method of the boron containing water of Claim 1 including the pH adjustment process of adjusting the pH of boron containing water to 9.5 or less.   The method for treating boron-containing water according to claim 1, further comprising a coagulation step of adding a polymer flocculant to the second treatment liquid to obtain an aggregate containing boron.   The method for treating boron-containing water according to any one of claims 1 to 3, wherein an initial concentration of boron in the boron-containing water is 200 mg / L or more.   The method for treating boron-containing water according to any one of claims 1 to 4, wherein the molar concentration of calcium hydroxide and calcium oxide added to any boron-containing water is 0.67 mmol% to 121 mmol%.   The addition molar concentration with respect to the boron-containing water of any one of the compound that dissolves in hydrogen peroxide and water to generate hydrogen peroxide is 1.5 mmol% to 180 mmol%. Treatment method for boron-containing water.   The initial concentration of boron in boron-containing water is 600 mg / L to 1,500 mg / L, and either calcium hydroxide or calcium oxide is used as component A, and dissolved in hydrogen peroxide and water to generate hydrogen peroxide. The boron-containing composition according to any one of claims 1 to 6, wherein A / B, which is a molar ratio of the A component to the B component, is 0.15 to 1.50 when any one of the compounds is used as the B component. Water treatment method. A first treatment step in which either calcium hydroxide or calcium oxide is added to boron-containing water to form a first treatment solution; and the first treatment solution is dissolved in hydrogen peroxide and water. And a second treatment step of adding any one of the compounds that generate hydrogen peroxide to obtain a second treatment liquid, and a method for treating boron-containing water at least.
When any one of the calcium hydroxide and calcium oxide is an A component, and any one of the hydrogen peroxide and a compound that generates hydrogen peroxide when dissolved in water is a B component, the A component and the B component A boron removal agent, wherein A / B, which is the molar ratio of 0.10, is 0.10 to 6.00.