JP3963100B2 - Method and apparatus for treating vanadium-containing water - Google Patents

Description

＊１）：ＰＳＡ分析は、２２５ｎｍ吸光度値（１０ｍｍセル）。
【００３０】
表１より、ＶイオンおよびＣａイオンともに、強酸性カチオン交換樹脂に十分に吸着されるが、Ｖイオンの方が少し選択性が強かった。またカチオン交換樹脂が酸化され溶出してくるポリスチレンスルホン酸は、混合しているＣｌ形アニオン交換樹脂に吸着され、処理水へのリークは僅かであった。
【００３１】
比較例１：
実施例１において、強酸性カチオン交換樹脂のみを用いて同条件で試験を行ったところ、処理水中のＣａイオンは０．１〜０．３ｍｇ／ｌ、Ｖイオンは０．２〜０．６ｍｇ／ｌ、通液倍数２００以上のＰＳＡは３．５〜６．５ｍｇ／ｌ、ＴＯＣは１．５〜３．０ｍｇ／ｌとなった。
【図面の簡単な説明】
【図１】実施形態の処理方法を示すフロー図である。
【符号の説明】
１ バナジウム除去塔
２ 混床
３ イオン交換装置
４ カチオン交換塔
５ アニオン交換塔
６ カチオン交換樹脂層
７ アニオン交換樹脂層[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for treating vanadium-containing water that removes vanadium and other impurities from water to be treated containing vanadium, and more particularly to a method for treating vanadium-containing water that removes vanadium and other impurities using an ion exchange resin.
[0002]
[Prior art]
Vanadium is used as a catalyst, and is contained in ash such as coal and petroleum, as well as in certain natural waters. Vanadium-containing water contains various forms of vanadium depending on its origin. Vanadium forms various compounds depending on the valence of -I to + V, and each compound has one in which vanadium dissociates into a cation and one in which it dissociates into an anion. When vanadium is contained in an ionized or ionizable state like a soluble salt, vanadium can be removed by ion exchange.
[0003]
In the above vanadium-containing water, the vanadium compound contained therein dissociates into cations can remove vanadium by cation exchange. Some groundwater in volcanic ash sites contain vanadium compounds that dissociate into cations, and vanadium-containing water containing such vanadium compounds can be removed by exchanging and adsorbing vanadium dissociated into cations using a cation exchange resin. Is possible.
[0004]
When vanadium-containing water is treated with a cation exchange resin as described above, vanadium is concentrated in the resin by exchange adsorption. However, vanadium compounds are widely used as catalysts, and there are differences in activity depending on the valence of vanadium or the type of compound, but many vanadium compounds have catalytic activity. When vanadium having such catalytic activity is concentrated in the cation exchange resin, the cation exchange resin is oxidized by the catalytic action, and a relatively high molecular decomposition product containing the exchange group of the cation exchange resin ( For example, polystyrene sulfonic acid) flows out and deteriorates, and the cation exchange activity tends to decrease. Also, relatively high molecular degradation products such as polystyrene sulfonic acid that flow out deteriorate the quality of the treated water, and if there is an anion exchange resin in the subsequent stage, it becomes a burden and shortens the regeneration cycle of the anion exchange resin. There is.
[0005]
[Problems to be solved by the invention]
The problem of the present invention is that it is possible to efficiently remove vanadium with a simple configuration and operation, and also to remove a decomposition product of the resin, thereby preventing deterioration of the ion exchange resin in the subsequent stage, It is to propose a method and apparatus for treating vanadium-containing water that can perform ion exchange without reducing ion exchange activity.
[0006]
[Means for Solving the Problems]
The present invention is the following method and apparatus for treating vanadium-containing water.
(1) a vanadium-containing water in front, with is contacted with a mixed bed of H-shaped strongly acidic cation exchange resin and Cl form strongly basic anion exchange resin to remove vanadium is replaced adsorbed on a cation exchange resin to be released The inside of the mixed bed is made acidic with H ions to increase the exchange adsorption efficiency of vanadium, and the decomposition product of the resin flowing out by the concentration of vanadium is adsorbed to the anion exchange resin,
A method for treating vanadium-containing water, wherein pure water is produced by contacting the treated water with a subsequent cation exchange resin and anion exchange resin to remove residual ions .
(2) The method according to the above (1) , wherein the mixed bed at the former stage is regenerated with the regeneration drainage of the cation exchange resin at the latter stage.
(3) The method according to (1) or (2) above, wherein the cation exchange resin in the mixed bed or the latter stage is regenerated with treated water at the initial stage of the mixed bed.
(4) The method according to any one of (1) to (3) above, wherein the cation exchange resin and / or anion exchange resin constituting the mixed bed is a used resin.
(5) Contact with vanadium-containing water to remove vanadium by exchanging and adsorbing to the cation exchange resin, and acidifying the inside of the mixed bed with the released H ions to increase the vanadium exchange and adsorption efficiency. A mixed bed in the preceding stage in which the H-type strongly acidic cation exchange resin and the Cl -type strongly basic anion exchange resin are mixed so that the decomposition product of the resin flowing out by
Processor of vanadium-containing water and a subsequent cation exchange resin layer and A anion exchange resin layer to produce a the contacted with pure water to remove residual ions treated water mixed bed.
[0007]
The vanadium-containing water to be treated in the present invention is water containing vanadium in a cation-exchangeable state, including water containing vanadium as a cation or in a state dissociable into a cation, but dissociated into anions. Vanadium, a vanadium compound that can be dissociated into anions, a vanadium compound that is not ionized, or other impurities may be included. As the vanadium-containing water to be treated in the present invention, those containing 0.1 μg / L or more of vanadium dissociated into cations or vanadium dissociable into cations are suitable. Specific examples of the vanadium-containing water to be treated in the present invention include natural water, river water, in particular, groundwater, underground water, deep well water, etc. of volcanic ash.
[0008]
As described above, vanadium forms a compound having a valence of −I to + V, and among these, + II to + V is common. Oxidation numbers II and III produce salts mainly as cations, but oxidation numbers IV often combine with oxygen to form VO ²⁺ salts. At an oxidation number V, a salt of metavanadate ion VO ₃ ⁻ is formed together with a salt of VO ³⁺ or VO ₂ ⁺ . V ₂ O _5, which is widely used as a catalyst, is amphoteric and hardly soluble in water. When dissolved in an acid, VO ₂ ⁺ is generated, and metavanadate ions are generated in an alkaline aqueous solution and dissociated into anions.
[0009]
Vanadium thus forms compounds of various valences. Natural water, especially groundwater, underground water, and deep well water in volcanic ash lands, often contains vanadium that dissociates into cations. In addition, wastewater discharged from a system using a vanadium catalyst includes those that dissociate into cations and those that dissociate into anions according to pH.
[0010]
In the present invention, vanadium-containing water is removed in the preceding stage by contacting with a mixed bed of H-type strongly acidic cation exchange resin and Cl -type strongly basic anion exchange resin to exchange and adsorb vanadium dissociated into cations on the cation exchange resin. To do. In this case, when the vanadium-containing water contains an anion in addition to the cation, the anion is exchanged and adsorbed on the anion exchange resin. The mixed bed is a layer in which an H-type strongly acidic cation exchange resin and a Cl-type strongly basic anion exchange resin are mixed, and the vanadium-containing water treatment apparatus of the present invention is an apparatus including such a mixed bed. In the following description, unless otherwise specified, the term “ion exchange” means “cation exchange and / or anion exchange”.
[0011]
As the cation exchange resin and anion exchange resin used in the mixed bed in the present invention, a granular or gel ion exchange resin generally used in water treatment can be used, but a used waste resin is used. It is preferable from the economical aspect. Such an ion exchange resin uses a copolymer of styrene and divinylbenzene as a base resin, a styrene having a cation exchange group is used as a cation exchange resin, and a styrene exchange resin having an anion exchange group as an anion exchange resin. .
[0012]
The cation exchange resin, Ru with a strong acid cation exchange resin with a sulfonic group as a cation-exchange group. Moreover the anion exchange resin, Ru with a strong base anion exchange resins with quaternary ammonium groups as anion-exchange groups.
When vanadium is adsorbed to such a cation exchange resin and anion exchange resin, vanadium is concentrated in the resin, so that a part of the resin is decomposed by its catalytic action, and a relatively high molecular decomposition product containing an exchange group Leaks. In the case of vanadium dissociated into cations, when adsorbed on the cation exchange resin, a relatively high-molecular anionic decomposition product such as polystyrene sulfonic acid flows out. The anionic decomposition product flowing out in this way is adsorbed on the anion exchange resin.
[0013]
In the present invention, the cation exchange resin and anion exchange resin used for mixed bed for removing vanadium are used in the H form for the cation exchange resin and in the Cl form for the anion exchange resin. To arrange for such ionic form is carried out by reproducing the mixed bed with hydrochloric acid. When an ion exchange device such as a pure water production device is provided in the subsequent stage, it can be regenerated by passing the regeneration drainage of the cation exchange resin, or it can be regenerated by treated water containing acid at the initial stage of water flow in the mixed bed. .
[0014]
When water to be treated containing vanadium is passed through the mixed bed, vanadium is exchange-adsorbed on the cation exchange resin, but other cations such as Na and Ca are also exchange-adsorbed and H ions are released. On the other hand, since the anion exchange resin is in a salt form, anions such as Cl and SO ₄ flow out without being exchanged and adsorbed. Therefore, the inside of the mixed bed becomes acidic, and the exchange adsorption efficiency of vanadium is increased. This acidic treated water can be used as a regenerant for the cation exchange resin in the latter ion exchange apparatus.
[0015]
The conditions for water flow can be the same as those for treatment by ordinary ion exchange. The water flow rate varies depending on the vanadium concentration of the water to be treated, the target value for water quality treatment, etc., but generally 5-100 L / L-Resin / hr, preferably 5-30 L / L-Resin / hr. Can do. The end of water flow can be determined by detecting the leakage of ions or the like in the treated water. In this case, when the vanadium-containing water contains other cations such as sodium in addition to vanadium like natural water, the process is terminated when the first leaking cations start leaking. Moreover, when vanadium containing water contains only vanadium, it can complete | finish when vanadium leaks.
[0016]
As the water flow continues, vanadium is exchanged and adsorbed in the ion exchange resin and concentrated in the resin. When ions etc. start to leak, stop water flow and start regeneration. Play is liquid passing the hydrochloric acid as described above as a regenerant, then extruded, to end the playback then washed with water or the like. As the regenerant, it is also possible to use the regenerated drainage of the cation exchange resin in the subsequent ion exchange apparatus or the mixed bed treated water. By regeneration, vanadium and other cations adsorbed on the cation exchange resin elute, the resin is regenerated to H form, and the anion exchange resin is also regenerated to Cl form. Done.
[0017]
The method and apparatus for treating vanadium-containing water by the mixed bed of the present invention can efficiently remove vanadium with a simple configuration and operation. In this case, by combining the H-type cation exchange resin and the Cl-type anion exchange resin, the pH can be lowered to increase the vanadium removal efficiency, and the anionic decomposition product can be adsorbed and removed. And the operation is simplified and the removal of vanadium and decomposition products is efficient.
[0018]
The treatment method and apparatus for vanadium-containing water using the mixed bed of the present invention can be applied to both wastewater treatment and water treatment as long as it is vanadium-containing water. When ion exchange is performed by providing an exchange device in the subsequent stage, it is preferable because vanadium is efficiently removed, deterioration of the ion exchange resin in the subsequent stage is prevented, and ion exchange can be performed efficiently.
[0019]
Ion exchanger provided downstream are those using a cation exchange resin and A anion exchange resins, pure water production system using both, ultrapure water production system can be used. In such an ion exchange apparatus, pretreatment for removing vanadium is not usually performed. Therefore, when vanadium-containing water is passed as treated water, the resin is deteriorated and the treatment performance is lowered. In such a case, if the vanadium removal device comprising the mixed bed is provided as a pretreatment device, vanadium is efficiently removed by a simple configuration and operation, and the deterioration of the ion exchange resin of the subsequent ion exchange device is prevented by vanadium. The ion exchange efficiency can be maintained high. In this case, since the mixed bed for removing vanadium only needs to remove vanadium, the used waste resin can be used, and the regeneration thereof can also be regenerated using the regenerated effluent of the subsequent cation exchange resin. As a result, ion exchange can be made more efficient without causing a significant cost increase.
[0020]
When the ion exchange apparatus is provided in the subsequent stage, a mixed bed of H-type strongly acidic cation exchange resin and Cl-type strongly basic anion exchange resin is arranged in the previous stage, and the cation exchange resin layer and the latter in the latter stage. placing the ion exchange device including vias anion exchange resin layer. As the subsequent ion exchange apparatus, an ion exchange apparatus that is usually used as a pure water production apparatus, an ultrapure water production apparatus, or the like is used. Known configurations and operations, reproduction methods, and the like can be employed. New cation exchange resins and anion exchange resins are used. As the regenerant, a new acid or alkali can be used, but the regenerated agent of the cation exchange resin may be treated water in the initial stage of the mixed bed. Further, when the mixed bed is regenerated using the regeneration drainage of the cation exchange resin, an efficient treatment can be performed.
[0021]
【The invention's effect】
According to the present invention, the vanadium-containing water in front, is contacted with a mixed bed of H-shaped strongly acidic cation exchange resin and Cl form strong base anion exchange resin vanadium is replaced adsorbed on a cation exchange resin to remove it At the same time, the inside of the mixed bed is acidified by the released H ions to increase the exchange adsorption efficiency of vanadium, the decomposition product of the resin flowing out by the concentration of vanadium is adsorbed on the anion exchange resin, and the treated water is added to the latter stage. Since pure water is produced by contacting with cation exchange resin and anion exchange resin to remove residual ions, vanadium can be efficiently removed with a simple configuration and operation, and a decomposition product of the resin also it can be removed, thereby preventing deterioration of the subsequent ion exchange resins, without reducing the ion-exchange activity, efficiently Lee The on-exchange it is possible to produce a line have pure water.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
Drawing 1 is a flow figure showing the vanadium content water treatment equipment of an embodiment. In FIG. 1, reference numeral 1 denotes a vanadium removal tower, which is filled with a mixed bed 2 of an H-form strongly acidic cation exchange resin and a Cl- form strongly basic anion exchange resin. 3 is an ion exchange device (pure water production device), which comprises a cation exchange column 4 and an anion exchange column 5, filled with an H-type cation exchange resin layer 6 and an OH-type anion exchange resin layer 7, respectively. . The treated water channel L1 communicates with the vanadium removal tower 1, the transfer channels L2 and L3 communicate with each other between the vanadium removal tower 1 and the cation exchange tower 4, and between the cation exchange tower 4 and the anion exchange tower 5, and the anion exchange resin tower 5 The treatment water channel L4 is in contact with. Further, the regenerant path L5 communicates with the cation exchange tower 4, the transfer path L6 communicates between the cation exchange tower 4 and the vanadium removal tower 1, and the regeneration drainage path L7 communicates with the vanadium removal tower 1 to regenerate to the anion exchange tower 5. The drug path L8 and the regeneration drainage path L9 communicate with each other.
[0023]
In the method for treating vanadium-containing water by the above-described treatment apparatus, vanadium-containing water as treated water is supplied to the vanadium removing tower 1 from the treated water channel L1 and passed through the mixed bed 2 to exchange and adsorb vanadium. At this time, since the inside of the column becomes acidic, the exchange adsorption efficiency of vanadium is increased. The decomposition product of the anionic resin produced by the concentration of vanadium is adsorbed by the anion exchange resin forming the mixed bed 2. The treated water in the vanadium removal tower 1 enters the cation exchange tower 4 of the ion exchange device 3 from the transfer path L2 and passes through the cation exchange resin layer 6 so that residual cations are exchanged and removed. The cation exchange treated water enters the anion exchange tower 5 from the transfer path L3 and passes through the anion exchange resin layer 7, whereby the anions are exchanged and adsorbed, and the treated water (pure water) is taken out from the treated water path L4.
[0024]
In the above treatment, vanadium is removed by the vanadium removal tower 1, so that vanadium is not adsorbed in the cation exchange resin layer 6, and therefore the cation exchange resin layer 6 is not deteriorated by vanadium. The performance is kept high. Further, the decomposition product of vanadium concentration is adsorbed on the anion exchange resin in the mixed bed 2 and therefore is not adsorbed on the anion exchange resin layer 7, so that the anion exchange capacity of the anion exchange resin layer 7 is maintained high. The Therefore, the ion exchange capacity of the ion exchange device 3 is maintained high, and efficient ion exchange can be performed.
[0025]
The above equipment is provided with auxiliary equipment such as washing water or air for washing (back washing), other piping, pumps, valves, deaeration and decarbonation equipment, etc. ing. Reproduction is supplied from the regenerant passage L5 to supply regenerant to (hydrochloric acid) to the cation exchange column 4 plays a cation exchange resin layer 6, the vanadium removal column 1 the reproduced drainage from the transfer passage L6 mixed bed 2 is regenerated and discharged from the regeneration drainage path L7. As a result, the cation exchange resin layer 6 is regenerated to H type, the cation exchange resin layer of the mixed bed 2 is regenerated to H type, and the anion exchange resin is regenerated to Cl type . A regenerant (alkali) is supplied to the anion exchange tower 5 from the regenerant path L8 to regenerate the anion exchange resin layer 7 into OH form, and the regenerated drainage is discharged from the regeneration drainage path L9. Operations such as backwashing, extrusion, and washing are the same as those of a normal ion exchange apparatus.
[0026]
【Example】
Hereinafter, the present invention will be described with reference to examples and comparative examples.
[0027]
Example 1
(Preparation of test resin)
60 ml of strongly acidic cation exchange resin (monoplus S100, manufactured by Bayer, trademark) and 120 ml of strongly basic anion exchange resin (trademark, manufactured by Levacit M500 Bayer) were mixed, and 180 ml of the mixed resin was placed in a glass column (28 mmφ × 500 mmH). Filled. Next, 500 ml of 5% HCl solution (regeneration level of about 400 g / l) is regenerated at a flow rate of 3 L / L-Resin / hr for the strongly acidic cation exchange resin, and the cation exchange resin is converted to H form to perform anion exchange. The resin was trimmed into Cl form.
Next, a test solution was prepared by extruding a chemical solution (recycled waste HCl solution) and washing with water.
[0028]
(Preparation of treated water)
About 4.65 g of vanadium sulfate oxide (VOSO ₄ · nH ₂ O) and about 3.65 g of calcium chloride (CaCl ₂ · 2H ₂ O) are dissolved in 20 liters of pure water, so that V ion and Ca ion are 50 mg / l respectively. It was prepared so that it might become.
(Water flow test)
Next, the water to be treated (V, Ca = 50 mg / l) was passed downward through the resin column at a water flow rate of 7.6 L / L-Resin / hr. The treated water was analyzed for the adsorption performance and the adsorption performance of the Cl-type anion exchange resin polystyrene sulfonic acid (PSA). The results are shown in Table 1. The treated water had a pH of 2.4 to 2.8.
[0029]
[Table 1]

* 1): PSA analysis is 225 nm absorbance value (10 mm cell).
[0030]
From Table 1, although both V ions and Ca ions are sufficiently adsorbed by the strongly acidic cation exchange resin, the V ions are slightly more selective. In addition, polystyrene sulfonic acid that was oxidized and eluted from the cation exchange resin was adsorbed by the mixed Cl-type anion exchange resin, and there was little leakage to the treated water.
[0031]
Comparative Example 1:
In Example 1, when the test was conducted using only the strong acid cation exchange resin under the same conditions, the Ca ion in the treated water was 0.1 to 0.3 mg / l, and the V ion was 0.2 to 0.6 mg / l. l, PSA having a flow rate of 200 or more was 3.5 to 6.5 mg / l, and TOC was 1.5 to 3.0 mg / l.
[Brief description of the drawings]
FIG. 1 is a flowchart illustrating a processing method according to an embodiment.
[Explanation of symbols]
1 Vanadium removal tower 2 Mixed bed 3 Ion exchange device 4 Cation exchange tower 5 Anion exchange tower 6 Cation exchange resin layer 7 Anion exchange resin layer

Claims (5)

The vanadium-containing water in front, with is contacted with a mixed bed of H-shaped strongly acidic cation exchange resin and Cl form strongly basic anion exchange resin to remove vanadium is replaced adsorbed on a cation exchange resin, by the emitted H ions By making the inside of the mixed bed acidic, the exchange adsorption efficiency of vanadium is increased, and the decomposition product of the resin flowing out by the concentration of vanadium is adsorbed on the anion exchange resin,
A method for treating vanadium-containing water, wherein pure water is produced by contacting the treated water with a subsequent cation exchange resin and anion exchange resin to remove residual ions . The method according to claim 1 , wherein the mixed bed in the former stage is regenerated with a regeneration drainage of the latter stage cation exchange resin. The method according to claim 1 or 2 , wherein the cation exchange resin in the mixed bed or the subsequent stage is regenerated with the treated water in the initial stage of the mixed bed. The method according to any one of claims 1 to 3 , wherein the cation exchange resin and / or anion exchange resin constituting the mixed bed is a used resin. Contact with vanadium-containing water to remove vanadium by exchanging and adsorbing to the cation exchange resin, making the inside of the mixed bed acidic by releasing H ions to increase the exchange adsorption efficiency of vanadium, and flowing out by concentration of vanadium. A pre- mixed bed in which a H-type strongly acidic cation exchange resin and a Cl -type strongly basic anion exchange resin are mixed so that the decomposition product of the resin is adsorbed on the anion exchange resin;
Processor of vanadium-containing water and a subsequent cation exchange resin layer and A anion exchange resin layer to produce a the contacted with pure water to remove residual ions treated water mixed bed.

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