KR101837740B1 - Methods of Phosphate Adsorption and Desorption in Water Using Zeolite Incorporated with Iron and Their Apparatus - Google Patents

Abstract

An object of the present invention is to provide a method for removing and regenerating phosphates in water by aluminosilicate containing an iron component capable of easily removing phosphates in water and an apparatus therefor. In order to achieve the object, the apparatus for removing phosphates comprises: an introduction tank; an adsorption tank; a desorption tank; and an outlet. The method for removing phosphates comprises: an inlet water treatment step; an adsorption pretreatment step; a phosphate removal step; and a discharge step, wherein the phosphate removal step comprises a reduction step for submerging a supersaturated iron-containing zeolite bound to the phosphates in an alkaline solution to reduce the phosphates to a previous state of phosphate adsorption.

Description

[0001] The present invention relates to a method for removing and regenerating phosphates in an aqueous solution containing aluminosilicate containing iron,

The present invention relates to a method and apparatus for removing and regenerating phosphates in water by an aluminosilicate containing an iron component, and more particularly, The present invention relates to a method and apparatus for removing and regenerating phosphate in water by aluminosilicate contained therein.

In general, sewage and wastewater contain not only organic matter but also nitrogen and phosphorus. When untreated nitrogen and phosphorus in wastewater treatment plants and wastewater treatment plants enter the lake, they cause eutrophication and cause red tides in the sea.

Typical methods for removal of phosphate in water include ion exchange, chemical precipitation by chemical treatment with iron or aluminum salt, and porous adsorption on the porous material, There is a way to remove it. There is also a surface precipitation method that removes phosphorus using nano zero valent iron or sponge iron instead of iron salt injection.

The method of removing phosphate by the ion exchange method according to the related art is a method in which zeolite is mixed with ammonia water (NH ₄ ⁺ ) to ion-exchange sodium (Na ₂ O) contained in zeolite with ammonia ion, (Zeolite-NaH ⁺ ) containing hydrogen ions (H ⁺ ) is prepared and used. The removal of phosphate contained in water is removed by binding with hydrogen ions. The flocculation and sedimentation method by the chemical treatment by the iron salt or the aluminum salt injection is a method of dissolving the aluminum salt (Al ₂ (SO ₄ ) ₃ ) or the iron salt (FeSO ₄ , FeCl ₃ ) Insoluble precipitates such as salts (AlPO ₄ ), iron phosphate (FePO ₄ ) and the like are generated and removed to form precipitates, thereby increasing the disposal cost of chemical sludge. In addition, the insoluble sediments are irreversible and thus can not be repeatedly used by regeneration.

In addition, in the case of silica gel or ZSM5-5 type zeolite, which is a porous material, the adsorption rate is very slow because a physical diffusion process necessary for adsorption is required. Further, in the case of the surface chemical precipitation method in which phosphorus is removed by using the conventional zero valence iron or reduced iron, insoluble iron phosphate precipitation is formed on the iron surface and irreversible reaction is impossible.

The conventional phosphate removal method for removing phosphate contained in contaminated water such as wastewater is a method in which phosphate is precipitated into solution with an insoluble salt such as FePO ₄ ↓ or AlPO ₄ ↓ using iron ion or aluminum ion as described above However, the inevitable reaction of producing an insoluble salt is a non-reversible reaction, in which iron ion or aluminum ion can not be regenerated, and chemical sludge such as insoluble salt is generated in a large amount. Thus, the conventional phosphate removal technology has a problem that the reaction rate is slow, disposal cost is large, regeneration is impossible, by-products such as chemical sludge are generated, and a lot of suspended substances are generated in the solution.

On the other hand, Korean Priority Patent Publication No. 10-1679793 and Korean Patent Laid-Open Publication No. 10-2015-0119329 disclose prior art related to the present invention.

(Document 1) Korea // Registration Patent Publication No. 10-1679793 (Document 2) Korea // Open Patent Publication No. 10-2015-0119329

In order to solve the problems of the prior art, the present invention provides a method for removing contaminants in water by using an adsorption unit containing zeolite containing an iron component, desorbing adsorbed contaminants, And a method for removing and regenerating phosphate in water by using an aluminosilicate containing the phosphoric acid and an apparatus therefor.

The present invention has been made in view of the above problems, and it is an object of the present invention to provide an apparatus and method for controlling the same.

According to another aspect of the present invention, there is provided an inflow port for introducing inflow water from the outside and maintaining the inflow water in an acidic state. An adsorption module communicating with the inflow tank and containing an iron component-containing zeolite and being immersed in an alkaline solution, the adsorption tank for removing phosphate in the inflow water; An adsorption module containing an alkaline solution and containing an iron component-containing zeolite which is supersaturated with a phosphate, is received and regenerated by reducing it to a state before the adsorption of the phosphate, thereby enabling repeated use; And an outlet for discharging the phosphorus-removed influent to the outside of the adsorption tank. The apparatus for removing phosphoric acid in water by an aluminosilicate containing an iron component is provided.

In the present invention, the pH of the solution in the inflow bath is preferably maintained at 6 or less.

In the present invention, it is preferable that the adsorption module is immersed in a solution having a pH of 10 or more.

In the present invention, the pH of the solution in the desorption tank is preferably maintained at 10 or more.

In the present invention, it is preferable to include a separation plate for separating the inflow tank and the adsorption tank, and the separation plate may include an inlet for allowing inflow water in the inflow tank to flow downward into the adsorption tank.

In the present invention, it is preferable that the adsorption tank is configured so that the inflow water flows in an upward flow after passing through the adsorption module.

In the present invention, it is preferable that the adsorption module includes at least one laminated adsorption unit having an inner surface coated with the iron-containing zeolite.

In the present invention, it is preferable that the at least one stacked adsorption unit is in the form of repeated hexagonal rings for allowing the inflow water to flow while being dispersed on the front surface of the adsorption module.

In the present invention, it is preferable that the at least one stacked adsorption unit is coated with the zirconium compound having the iron component bonded to the skeleton of the aluminosilicate by injecting ammonia iron citrate into the inner surface.

In the present invention, it is preferable that the inflow vessel includes an air supply for mixing the inflow water with the acidic solution added to the inflow tank.

According to still another aspect of the present invention, there is provided a method for treating an inflow water, comprising: an influent treatment step of maintaining the pH of influent water acidic; An adsorption pretreatment step of immersing the iron component-containing zeolite in an alkaline solution; A phosphate removal step of flowing the influent water treated by the influent water treatment step into the iron component-containing zeolite solution precipitated in the alkaline solution to remove phosphate; And a discharging step of discharging the phosphate-removed influent water to the outside, wherein the phosphate removing step comprises a reducing step of dipping the supersaturated iron component-containing zeolite with phosphate in an alkaline solution to reduce the phosphate to the pre-adsorbed state There is provided a method for removing phosphate in water by an aluminosilicate containing an iron component.

In the present invention, it is preferable that the adsorption pretreatment step is performed for 1 minute or more.

In the present invention, it is preferable that the phosphate removing step is performed for 10 minutes or more.

In the present invention, it is preferable that the reducing step is performed for 30 minutes or more.

The method and apparatus for removing and regenerating phosphates in water by an aluminosilicate containing an iron component according to the present invention provide the following effects.

The present invention can remove phosphates in water and can be repeatedly regenerated by using an adsorption unit containing a zeolite containing an iron component, so that it is possible to reduce the recycling cost of an apparatus for removing phosphates in water by an aluminosilicate containing an iron component There is an effect.

The effects of the present invention are not limited to those mentioned above, and other effects not mentioned can be clearly understood by those skilled in the art from the following description.

Fig. 1 (a) shows an apparatus for removing and regenerating phosphates in water by an aluminosilicate containing an iron component according to the present invention, and Fig. 1 (b) 1 (c) shows an adsorption unit included in an adsorption module of an apparatus for removing and regenerating phosphates in water by an aluminosilicate containing an iron component. FIG.
2 shows a method for removing and regenerating phosphate in water by an aluminosilicate containing an iron component according to the present invention.
FIG. 3 shows changes in phosphate concentration with time in the inflow water maintained at pH 5 after pretreatment at pH 5 for each method of incorporating the iron component into the adsorption unit containing zeolite of each kind, and FIG. In a desorption tank containing an alkaline solution, the adsorption unit containing the iron component is subjected to pretreatment, followed by a change in phosphate concentration (batch) in the influent of pH 5 substituted with an acidic solution.
Fig. 5 shows the regeneration (batch) amount in the alkaline solution of the adsorption unit to which the phosphate is adsorbed.
Figure 6 shows the elution (batch) amount for the iron component in the acidic solution.
Figure 7 shows the results of a continuous phosphate removal experiment.
FIG. 8 is an electron microscopic observation image of the iron component contained in the adsorption unit (AIC-ZA) after repeated adsorption and desorption of phosphate. FIG. 8 (a) The screen after the experiment is shown.
10 shows the result of XPS scan of aluminum (Al) component after phosphate adsorption and desorption, and FIG. 11 shows the results of XPS scan of phosphorus after adsorption and desorption of phosphorus (Fe). FIG. Component XPS scan results.

The description of the present invention is merely an example for structural or functional explanation, and the scope of the present invention should not be construed as being limited by the embodiments described in the text. That is, the embodiments are to be construed as being variously embodied and having various forms, so that the scope of the present invention should be understood to include equivalents capable of realizing technical ideas. Also, the purpose or effect of the present invention should not be construed as limiting the scope of the present invention, since it does not mean that a specific embodiment should include all or only such effect.

Meanwhile, the meaning of the terms described in the present application should be understood as follows.

The terms "first "," second ", and the like are intended to distinguish one element from another, and the scope of the right should not be limited by these terms. For example, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component.

It is to be understood that when an element is referred to as being "connected" to another element, it may be directly connected to the other element, but there may be other elements in between. On the other hand, when an element is referred to as being "directly connected" to another element, it should be understood that there are no other elements in between. On the other hand, other expressions that describe the relationship between components, such as "between" and "between" or "neighboring to" and "directly adjacent to" should be interpreted as well.

It is to be understood that the singular " include "or" have ", as used herein, is intended to encompass a plurality of expressions, unless the context clearly dictates otherwise, It is to be understood that the combination is intended to specify the presence or absence of one or more other features, numbers, steps, steps, components, components, or combinations thereof in any way whatsoever.

In each step, the identification code (e.g., a, b, c, etc.) is used for convenience of explanation, the identification code does not describe the order of each step, Unless otherwise stated, it may occur differently from the stated order. That is, each step may occur in the same order as described, may be performed substantially concurrently, or may be performed in reverse order.

All terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs, unless otherwise defined. Commonly used predefined terms should be interpreted to be consistent with the meanings in the context of the related art and can not be interpreted as having ideal or overly formal meaning unless explicitly defined in the present application.

In the present specification, 'iron-containing aluminosilicate' means iron ion-exchanged zeolite prepared by mixing zeolite with an inorganic iron salt solution containing FeCl ₃ , FeSO ₄ or Fe (NO ₃ ) ₂ , a synthesis of zeolite Iron salt-injected zeolite to which an iron salt is applied to an adsorption unit and ammonium iron cationate as a binding compound in a zeolite synthesis process are injected to form an iron complex compound in which an iron component is chemically bonded to the skeleton of the aluminosilicate Zeolite or mixtures thereof.

Hereinafter, a method and apparatus for removing and regenerating phosphates in water by an aluminosilicate containing an iron component according to a preferred embodiment of the present invention will be described in detail with reference to FIGS. 1 to 11. FIG.

Fig. 1 (a) shows an apparatus for removing and regenerating phosphates in water by an aluminosilicate containing an iron component according to the present invention, and Fig. 1 (b) 1 (c) shows an adsorption unit included in an adsorption module of an apparatus for removing and regenerating phosphates in water by an aluminosilicate containing an iron component. FIG.

As shown in FIG. 1 (a), according to the present invention, an apparatus 100 for removing and regenerating phosphates in water by aluminosilicate containing an iron component comprises an inlet tank 101 through which inflow water flows from the outside, The adsorption tank 102 communicating with the tank 101 for removing phosphate in the influent water and the adsorption module containing the iron component-containing zeolite contained in the adsorption tank are saturated, (Not shown).

For example, the apparatus for removing and regenerating phosphates in water by an aluminosilicate containing an iron component includes a separation plate 106 for separating the inflow tank 101 and the adsorption tank 102, And an inlet 107 for introducing the inflow water into the adsorption tank 102. [

The influent water flowing into the inflow bath 101 is preferably kept acidic. For example, the pH of the influent water may be maintained at pH 6 or lower, but it is preferred that the pH in the inflow bath 101 be 5-6. The acid solution injected into the inlet tank 101 may be sulfuric acid.

The inlet vessel 101 may be equipped with a stirring device (for example, a stirrer, an air supply device) 111 for thorough mixing of the wastewater. The sulfuric acid is injected into the inflow bath 101 and mixed by the stirring device 111 so that the solution in the inflow bath 101 can be kept acidic.

The inflow tank 101 is a water tank into which wastewater containing phosphate is introduced, and wastewater can be introduced from the outside. (Cl ^- ), nitrate (NO ₃ ^- ), sulfate (SO ₄ ^2- ), carbonate (HCO ₃ ^- , CO ₃ ^2- ), phosphate (PO ₄ ^3- , HPO ₄ ^{2 -} a plurality of ion salts containing a) may be present.

The inflow bath 101 configured as above is separated from the adsorption bath 102 by the separation plate 106.

The lower end of the separation plate 106 is penetrated so that the inflow water of the inflow tank 101 flows downward through the inflow opening 107 and the inflow water flows out of the space between the separation plate 106 and the absorption tank 102 And flows into the adsorption tank 102 through the upper end of the separation plate 106.

The adsorption tank 102 is for removing phosphate in the influent water by the adsorption module 108. The contact time between the influent water and the adsorption tank 102 may be about 10 minutes or more.

As shown in Fig. 1 (b), according to the present invention, the adsorption module 108 is for removing phosphate in the influent water, and may contain an iron component-containing zeolite and may be accommodated in the adsorption bath 102 .

The adsorption module 108 may include at least one adsorption unit 104.

The adsorption unit 104 is for removing phosphate by a zeolite containing an iron component applied to the inner surface 105. The adsorption module 108 may be configured such that at least one adsorption unit 104 is stacked on top of each other have.

The adsorption module 108 can pass influent water through at least one adsorption unit 104 and contaminants in the influent can be adsorbed by the iron component zeolite applied to at least one adsorption unit 104, The effluent, which is the influent from which the material has been removed, can be discharged through the outlet 109.

1 (c), according to the present invention, the adsorption unit 104 is configured such that the hexagonal pillar shape is repeatedly formed so that the inflow water containing phosphate is dispersed on the front surface of the adsorption tank 102, ≪ / RTI >

The adsorption unit 104 includes an inner surface 105 formed on the inner side of the hexagonal structure and a zeolite containing an iron component can be applied on the inner surface 105.

For example, the inner surface 105 may be coated with an aluminosilicate comprising sodium phosphate, aluminum hydroxyl phosphate or Iron hydroxyl phosphate.

Accordingly, the adsorption unit 104 comprising an aluminosilicate containing an iron component may include sodium aluminosilicate, i.e., a zeolite containing Na ₂ O, SiO ₂ , Al ₂ O ₃ .

The iron component-containing zeolite applied to the adsorption unit 104 can be prepared as follows. In one example, the zeolite can be mixed with an inorganic iron salt solution comprising FeCl ₃ , FeSO ₄ or Fe (NO ₃ ) ₂ , wherein the adsorption unit in the inorganic iron salt solution comprises an iron component by ion exchange An adsorption unit containing an iron-exchanged zeolite (IE-ZA) can be produced. In another example, an adsorption unit may be produced by injecting an inorganic iron salt into the synthesis process of the zeolite and containing an iron injected zeolite (II-ZA) coated with an iron salt on the adsorption unit. Another example is the introduction of ammonium iron citrate (AIC) as an iron chelated complex in the zeolite synthesis process to form iron complexes in which the iron component is chemically bonded to the skeleton of the aluminosilicate An adsorption unit containing zeolite (AIC zeolite, AIC-ZA) can be produced.

For example, the phosphate in the influent may be adsorbed by the adsorption unit 104 by synthesizing sodium phosphate, aluminum hydroxyl phosphate or Iron hydroxyl phosphate contained in the adsorption unit 104 .

The inflow water can flow in the upward direction after passing through the adsorption module 108 accommodated in the adsorption tank 102 and the outflow port 109 for discharging the effluent water is provided at the upper end of the adsorption tank 102, The removed effluent can be discharged to the outside.

The desorption tank 103 serves to reduce the phosphorus adsorbed on the adsorption module 108 and reuse it when the adsorption rate of the adsorption module 108 adsorbed on the adsorption tank 102 is supersaturated. The desorption tank 103 may be provided separately from the adsorption tank 102 or may be formed in association with the adsorption tank 102.

When the adsorption module 108 saturated with the phosphate adsorption is separated from the adsorption tank 102 and put into the desorption tank 103 and the solution of the desorption tank 103 is maintained in an alkaline solution having a pH of 10 or more, (OH) ₂ ⁺ or Fe ₂ (OH) ₄ ^{2 +} ) containing a hydroxyl group, which is beneficial for phosphate absorption, and an aluminum-containing zeolite containing a hydroxyl group It can be regenerated as a salt (Al (OH) ₂ ⁺ or Al ₂ (OH) ₄ ^{2 +} ) and can be used repeatedly. In addition, chemical sludge does not occur due to phosphate removal by such adsorption.

2 shows a method for removing and regenerating phosphate in water by an aluminosilicate containing an iron component according to the present invention.

As shown in FIG. 2, according to the present invention, a method for removing and regenerating phosphates in water by an aluminosilicate containing an iron component includes an influent water treatment step (201) for maintaining the pH of influent water acidic; An adsorption pretreatment step (203) of immersing the iron component-containing zeolite in the acidic solution; A phosphate removal step (205) for removing the phosphate by introducing the influent water treated by the influent water treatment step into the iron component-containing zeolite solution precipitated in the alkaline solution; And a desorption step (207) for discharging the phosphate-depleted influent water to the outside. In the phosphate removal step, a reducing step of dipping the supersaturated iron component-containing zeolite in the alkaline solution to reduce the phosphate- 209).

For example, the influent water treatment step 201 may be performed for one minute or more.

For example, the adsorption unit 104 may be pretreated with an acidic solution having a pH of 5 or lower, so that contaminants can be adsorbed more quickly. The chloride, nitrate or sulphate in the influent may be semiconducting with the cationic iron hydroxide mixture or aluminum hydroxide mixture contained in the adsorption unit with a low ionization tendency. The carbonate acts as an interfering substance in the course of adsorption of the phosphate on the adsorption unit and can compete. The carbonate in the influent can be replaced with CO ₂ and removed from the influent. To allow the carbonate in the influent to be removed with CO ₂ , an acidic solution may be added to the influent to replace the pH of the influent with an acidic solution of pH 6 to pH 6. The Na ₂ O component contained in the adsorption unit 104 can be converted to the cationized Na ₂ H ⁺ by lowering the pH of the influent water and replacing it with an acidic solution.

Whereby a sodium salt for adsorbing the phosphate to the adsorption unit 104 can be generated. The sodium salt can be used to remove the carbonate in the influent with CO ₂ , which is advantageous for adsorbing the phosphate in the influent.

The adsorption pretreatment step 203 may be performed for one minute or more.

For example, the adsorption unit 104 is pretreated with an alkaline solution having a pH of 10 or higher, so that contaminants can be adsorbed more quickly.

The adsorption unit 104 can be immersed in a solution containing an alkaline solution. Aluminum ingredients contained in absorption unit 104 is a hydroxyl ion (OH ^-) and the reaction to cationic aluminum hydroxide mixture (anionic hydroxoaluminiumcomplex, Al (OH) 2 +, Al 2 (OH) 4 2+) is .

An aluminum salt (or an aluminum hydroxide mixture) for adsorbing phosphate to the adsorption unit 104 can be generated and released into the influent water. The aluminum salt can be used to advantageously remove the phosphate in the influent.

Further, the iron components contained in the absorption unit (104) is a hydroxyl ion (OH ^-) and the reaction cationized iron hydroxide mixture (anionic hydroxoironcomplex, Fe (OH) ₂ ^+, Fe ₂ (OH) ₄ ²⁺ May be formed.

Thus, a ferrous salt (or iron hydroxide mixture) for adsorbing phosphate to the adsorption unit 104 can be generated and released into the influent water. It is possible to advantageously remove the phosphate in the inflow water by using the iron salt.

The phosphate removal step 205 may be performed for 10 minutes or more.

When the inflow water flowing from the outside into the inflow bath 101 communicates with the inflow bath 101 and flows into the adsorption tank 102 containing the absorption module 108 including the absorption unit 104, Can be adsorbed to at least one stacked adsorption unit (104).

The phosphate in the influent water is adsorbed to the adsorption unit 104 by the sodium phosphate, aluminum hydroxyl phosphate or iron hydroxyl phosphate contained in the adsorption unit 104 as shown in the following formulas (1), (2) (Not shown).

≪ Formula 1 >

Na ₂ H ⁺ + HPO ₄ ^{2 -} or PO ₄ ^3- -> NaH ₂ PO ₄ , Na ₂ HPO ₄

(2)

_{^{Al (OH) +2 or Al 2}} (OH) 2 +4 + HPO 4 2 - or PO 4 3- -> Al x · (OH)) y · (PO 4) z

(3)

_{^{Fe (OH) +2 or Fe 2}} (OH) 2 +4 + HPO 4 2 - or PO 4 3- -> Fe x · (OH) y · (PO 4) z

The desorbing step 207 may include the step of passing the phosphate-depleted inflow water through the adsorption module 108 and discharging it to the outlet 109 in an upward flow.

The reduction step 209 may be performed for 30 minutes or more.

For example, the phosphate adsorbed to the adsorption unit 104 may be replaced by a ligand exchange.

For example, even after the adsorption unit 104 is adsorbed with phosphate ions in the influent water, the adsorption unit 104 can be made as a reversible reactant capable of regeneration. The adsorption unit 104 can be immersed in a desorption tank 103 containing an alkaline solution having a pH of 10 or more.

For example, Al _x. (OH) _y. (PO ₄ ) _z and Fe _x. (OH) _y. (PO ₄ ) _z included in the adsorption unit 104 include a hydroxyl group favorable for phosphate adsorption (Al (OH) ₂ ⁺ or Al ₂ (OH) ₄ ^{2 +} ) containing iron (Fe (OH) ₂ ⁺ or Fe ₂ (OH) ₄ ²⁺ ) and a hydroxyl group and repeatedly reused So that there is no chemical sludge as a result of phosphate removal due to the adsorption of phosphate, as in the prior art.

According to the present invention, a method for removing and regenerating phosphates in water by an aluminosilicate containing an iron component is characterized in that after the reduction step 209 is carried out, an influent treatment step 201, an adsorption pretreatment step 203, (Not shown) in which the reduction step 209 is repeatedly performed following the step 205, the discharging step 207, and the like.

Hereinafter, with reference to FIG. 3 to FIG. 11, the removal efficiency by the method of removing phosphates in water by the aluminosilicate containing iron component according to the present invention will be explained using experimental data.

The experiment for removing phosphate in water by the aluminosilicate containing iron components shown in Figs. 3 to 6 is a batch experiment.

First, the batch experiment was conducted on phosphate removal efficiency to adsorb phosphate in the influent water according to the steps of providing an adsorption unit containing an iron component in an adsorption unit containing an iron component and precipitating the adsorption unit in an alkaline solution. As the comparative substance, a ferrous ion exchange adsorption unit, an iron salt injection adsorption unit, and a ferrous chloride compound AIC manufactured using FeCl ₃ were used as a reference material, And compared with a stick adsorption unit.

The iron content of each material was about 2% and the molar ratios of the constituents were Na ₂ O: SiO ₂ : Al ₂ O ₃ : Fe: H ₂ O = 3.1: 2.0: 1.0: 0.1: And an adsorption unit containing 2 g of iron component was used for each. Influent concentration of phosphate (PO ₄ ^- P ^3-) is fixed to 8mg / L and, pH of the influent substituted with an acidic solution was adjusted to 5.5 using sulfuric acid solution, the test target sample is passed through the pre-treatment of iron at pH 5 The adsorption capacity of the adsorption unit containing phosphate and the phosphate adsorption capacity including the pretreated iron component at pH 10 was compared. And the optimum pH for regenerating the adsorption unit adsorbing phosphate by using the desorption bath was examined. It was also examined whether the iron components were desorbed under acidic conditions for each adsorption unit.

The optimum pH for the desorption of adsorbed phosphate was also investigated. Batch experiment contents and results will be described with reference to Figs. 3 to 6 below.

FIG. 3 shows changes in phosphate concentration with time in the inflow water maintained at pH 5 after pretreatment at pH 5 for each method of incorporating the iron component into the adsorption unit containing zeolite of each kind, and FIG. In a desorption tank containing an alkaline solution, the adsorption unit containing the iron component is subjected to pretreatment, and then the concentration of phosphate (batch) is shown in the influent water at pH 5 substituted with the acid solution.

As shown in FIG. 3 and FIG. 4, the removal efficiency of phosphate of the adsorption unit shown in FIG. 3 is relatively low as compared with the case of pretreating the adsorption unit shown in FIG. 4 with the alkaline solution, I did. When the adsorption unit containing zeolite containing iron component was pretreated with an acid solution, the concentration of phosphate in the influent water flowing into the adsorption tank increased with the lapse of 0, 1, 5, 10, 20, 40, The amount of iron contained in the adsorbent unit containing zeolite was reduced to 1.8 mg / L for a total of 60 minutes, In the case of the adsorption unit pretreated with an alkaline solution, the concentration of phosphate in the influent influxed into the adsorption tank was 8, 7.5, 6.2, 4.5, and 4.5 times as the reaction time elapsed from 0, 1, 5, 10, 20, 3.8, 3.5, and 3.5 mg / L, respectively, indicating a decrease of 4.5 mg / L over a total of 60 minutes.

In particular, as shown in FIG. 4, it can be confirmed that the adsorption unit made of AIC (iron complex zeolite) has the highest phosphoric acid adsorption efficiency in containing an iron component. In the case of the adsorption unit containing only zeolite, the concentration of phosphate in the influent water flowing into the adsorption tank was 8, 7.5, 6.2, 4.5, 3.8 and 3.5 times as the reaction time elapsed from 0, 1, 5, 10, 20, , And 3.5 mg / L, respectively. In contrast, the adsorption unit containing the zirconium compound zeolite showed a reaction time of 0, 1, 5, 10, 20, 40 and 60 minutes , The concentration of phosphate in the influent water flowing into the adsorption column decreased to 8, 1.2, 0.5, 0.3, 0.2, 0.1, and 0.08 mg / L, and decreased by 7.92 mg / L during the total 60 minutes. This is because, in the case of the adsorption unit made of AIC, since the iron component is contained in the skeleton structure of the aluminosilicate, adsorption and desorption of the adsorption unit can be repeated and reusable. Therefore, not only the sodium salt, And it is confirmed that it is possible to repeatedly carry out adsorption-desorption of contaminants.

Fig. 5 shows the regeneration (batch) amount in the alkaline solution of the adsorption unit to which the phosphate is adsorbed.

As shown in FIG. 5, it was confirmed that the adsorbed phosphate at pH 10 was mostly desorbed from the adsorption unit as a result of performing pH as a dependent variable in order to desorb the phosphate adsorbed on the iron complex adsorption unit. In the case of the neutral solution of pH 7, the concentration of the iron salt or the aluminum salt to be regenerated is about 0.3 ppm to 0.5 ppm even after 120 minutes, It can be confirmed that the amount increased from 0.3 ppm to 6 ppm with the lapse of 120 minutes.

Accordingly, in order to desorb phosphate in water using an adsorption unit containing an iron component, an adsorption unit containing an iron component is pretreated with an alkaline solution having a pH of 10 or more, the pH of the influent containing phosphate is adjusted to an acidic condition of 5 Most preferred is treatment.

In order to regenerate the adsorption unit containing the iron-adsorbed iron component and to use it repeatedly, it is most appropriate to regenerate it in an alkaline solution having a pH of 10 or more.

In addition, according to the experimental results shown in FIG. 5, the principle of chemical adsorption of phosphate according to the present invention is based on binding and exchange with NaH, AlOH and FeOH, that is, ligand exchange with a hydroxyl group bonded with a metal ion This is a reaction to the above.

Figure 6 shows the elution (batch) amount for the iron component in the acidic solution.

As shown in FIG. 6, in the case of the iron ion exchange sorption unit and the iron salt injection sorption unit, the iron component was eluted as a result of dissolution test for the iron component in each adsorption unit under acidic conditions, but the iron component was bonded to the aluminosilicate skeleton It can be confirmed that a relatively small amount of iron component is eluted in the case of the adsorbing unit of the adsorbent. For example, in the case of an adsorption unit containing a zeolite containing an iron component by an iron ion exchange method, the iron component in the influent water is 0.2 mg / L whereas in the case of the adsorption unit comprising the zeolite compound zeolite, the iron component in the influent water is 0.001 mg / L, which is relatively small. As a result, it was found that the iron complex compound adsorption unit is the most advantageous in the case of reusing the adsorption unit.

The phosphate concentration removal efficiency of influent and effluent will be described below with reference to FIGS. 7 to 11. FIG. In the continuous experiment, the influent flow was adjusted to about 20 L / min and the pH of the influent water was adjusted to 5, and the mixing time was maintained at 1 minute. The mixing time was maintained at about 10 minutes in the honeycomb adsorption tank.

Figure 7 shows the results of a continuous phosphate removal experiment.

As shown in FIG. 7, it was confirmed that the removal efficiency of phosphate was 99% as the experiment days passed. At the first day of the experiment, the phosphate concentration was 8.5 mg / L in the influent and decreased by 8.4 mg / L in the effluent at 0.1 mg / L in the effluent, and the phosphate concentration in the effluent was 8.5 mg / L and it was decreased to 0.05 mg / L in effluent by 8.45 mg / L.

FIG. 8 is an electron microscopic observation image of the iron component contained in the adsorption unit (AIC-ZA) after repeated adsorption and desorption of phosphate. FIG. 8 (a) The screen after the experiment is shown.

As shown in FIG. 8, it can be confirmed that the iron component contained in the adsorbent-adsorbing unit was the same as that of the adsorption-desorption repeated experiment before and after the experiment, that is, 10 μm.

10 shows the result of XPS scan of aluminum (Al) component after phosphate adsorption and desorption, and FIG. 11 shows the results of XPS scan of phosphorus after adsorption and desorption of phosphorus (Fe). FIG. Component XPS scan results.

As shown in FIGS. 9 to 11, the binding energy of the phosphorus component, the iron component and the aluminum component after the phosphate adsorption-desorption by using XPS was examined. As a result, after the phosphate desorption, can confirm.

The embodiments and the accompanying drawings described in the present specification are merely illustrative of some of the technical ideas included in the present invention. Therefore, it is to be understood that the embodiments disclosed herein are not for purposes of limiting the technical idea of the present invention, but rather are not intended to limit the scope of the technical idea of the present invention. It will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

100: Phosphate removal and regeneration device in water by aluminosilicate containing iron component
101: Inflow tank
102: adsorption tank
103: Desorption tank
104: Adsorption unit
105: inner surface
106: separation plate
107: inlet
108: Adsorption module
109: Outlet
111: air supply

Claims (14)

An inflow tank for introducing inflow water from the outside and maintaining the inflow water at a pH of 6 or less;
An adsorption tank communicating with the inflow tank and containing an adsorption module including at least one laminated adsorption unit having an inner surface coated with iron-containing zeolite, for removing phosphate in the inflow water;
a desorption tank containing an alkaline solution maintained at a pH of 10 or more and capable of being repeatedly used by receiving and regenerating an adsorption module containing an iron component-containing zeolite which is supersaturated with phosphate to reduce the phosphate to a state before adsorption; And
And an outlet for discharging the phosphate-removed influent water to the outside of the adsorption tank,
The iron-containing zeolite may be prepared by injecting ammonium iron citrate (AIC) as an iron chelated complex in the synthesis of zeolite, thereby forming an iron complex zeolite formed by chemically bonding an iron component to the framework of the aluminosilicate (AIC zeolite, AIC-ZA)
Wherein the adsorption unit is pretreated by immersing it in an alkaline solution having a pH of 10 or more, and an apparatus for removing and regenerating phosphates in water by an aluminosilicate containing an iron component.
delete delete delete The method according to claim 1,
And a separation plate for separating the inflow bath and the adsorption bath,
Wherein the separator comprises an inlet for allowing influent water in the inlet vessel to flow downward into the adsorption vessel
An apparatus for removing and regenerating phosphates in water by an aluminosilicate containing an iron component.
The method according to claim 1,
The adsorption vessel
And the inflow water flows in an upward flow after passing through the adsorption module
An apparatus for removing and regenerating phosphates in water by an aluminosilicate containing an iron component.
delete The method according to claim 1,
Wherein the at least one stacked adsorption unit has a hexagonal column for repeatedly flowing the inflow water while dispersed and contacting the front surface of the adsorption module
An apparatus for removing and regenerating phosphates in water by an aluminosilicate containing an iron component.
delete The method according to claim 1,
Wherein the inlet vessel comprises an agitator for mixing the acidic solution added to the inlet vessel and the influent water
An apparatus for removing and regenerating phosphates in water by an aluminosilicate containing an iron component.
delete delete delete delete

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