KR20160004063A - Removal system of sulfate in seawater using ion exchange resin - Google Patents

Abstract

The present invention relates to a system for removing a sulfate ion of seawater using an ion exchange apparatus, which makes a mineral hardness component such as a calcium ion, a magnesium ion, etc. left while removing an anion such as a sulfate ion or the like from seawater by using anion change resin to satisfy 250 mg/L of sulfate ion concentration, which is a drinking water quality standard item, when manufacturing high hardness drinking water containing the large amount of minerals through a seawater desalination process. The system for removing a sulfate icon from seawater by using an ion exchange apparatus can make a selective mineral left by using a complex method of a system of an electrodialysis (ED) and an icon exchange (IX) system in mineral concentrated water in which the minerals such as calcium, magnesium, etc. are concentrated in a nanofiltering method, and remove a certain material such as the chlorine ion, the sulfate ion, etc. by using the system of the ED and the IX.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a sulfate ion removal system,

The present invention relates to a specific ion removal method in seawater, and more particularly, to a method for removing specific ions in seawater, and more particularly, to a method for removing specific ions in seawater by using an ion exchange resin or the like, Removing the anion by linking with various seawater desalination apparatuses and ion exchange resin methods, and regenerating the used ion exchange resin. In order to remove harmful components from existing seawater desalination processes, To an improved method.

1kg of seawater contained 96.5g (96.5%) of water, 18.98g (1.9%) of chlorine ion, 10.556g (1.1%) of sodium ion, 2.649g (0.3%) of sulfuric acid ion and 1.272g 0.4 g (0.04%) of calcium ion, 0.38 g (0.04%) of potassium ion and 0.14 g (0.01%) of bicarbonate ion are present. The cation and anion of these main components are dissolved in 1.0 kg of sea water in total 3.4% and the remaining 0.1% is dissolved in trace metals and a total of 92 kinds of dissolved substances are known to exist in seawater.

Traditionally, seawater has been desalted by evaporation, and membrane separation or electrodialysis has been used recently. The evaporation method used the principle of condensing water vapor by evaporating seawater. The membrane-based desalination method uses an ionic material dissolved in water as a membrane to exclude salts and pass pure water only. In the electrodialysis method, an anion membrane and a cation membrane are alternately arranged, and then an anion membrane A direct current voltage is applied to the electrodes located at both ends of the cation membrane to remove the positive ions and the negative ions to obtain pure fresh water. Conventional methods for separating minerals from seawater are methods for separating mineral salts such as sodium chloride, calcium carbonate, calcium chloride, magnesium sulfate, and magnesium chloride by evaporating and concentrating seawater.

However, when these minerals extraction methods are used, it is difficult to efficiently separate calcium and magnesium from various minerals contained in seawater, and there is a disadvantage in that the recovery rate of mineral components is low and energy is large. Since the mineral salts extracted by the above-described mineral extraction method are combined with cations to form salts without removing the anions such as chloride ion (Cl ^- ) and sulfate ion (SO ₄ ^2- ), the mineral salts are dissolved again to form minerals When producing water, it is disadvantageous that it is impossible to manufacture high-hardness water having a hardness of 400 or higher because the chlorine ion and the sulfate ion are re-dissolved as the water quality standards of the water to be consumed. In addition, the process of producing high hardness water using evaporation method is energy consuming system which consumes a large amount of energy to evaporate seawater during the process of concentrating seawater.

The present invention relates to a method for preparing a high-purity water containing a large amount of minerals through a desalination process using an anion exchange resin so as to satisfy a sulfate ion concentration of 250 mg / L, The anion is removed, while the mineral hardness components such as calcium ions and magnesium ions remain.

As the mineral hardness component, which is a problem of the existing desalination method (evaporation method, reverse osmosis method), increases, the concentration of sulfuric acid ion also increases, and in the hardness water having hardness of 400 mg / L or more, the sulfate ion and chlorine ion In order to overcome the technical limitations that can not be overcome, the system for removing sulfuric acid from seawater using ion exchanger is a system that uses electrodialysis (ED) and ion exchange (ion exchange) in minerally concentrated water, which is enriched with minerals such as calcium and magnesium, (ED) and the ion exchange system (IX) can be used to remove specific substances such as chloride ions and sulfate ions while leaving selective minerals using a complex method of the ion exchange system (IX) system.

By using the NF / IX / ED linkage process, the mineral water content of the seawater desalination process is increased while the sulfate ion and chlorine ion are removed. This high hardness premium is intended to provide a way to manufacture water to eat. Also included are methods for regenerating ion exchange resins used for economical use of used ion exchange resins (IX).

Korean Patent Publication No. 10-891320000 discloses a method for producing treated water using deep sea water. More specifically, deep sea water having a property different from that of seawater in a deep sea below 200 m in depth is stored in a house, After having been sent to the tank, the remaining one except for the deep sea water used for fisheries and agriculture, the one-stage osmosis process tank, the two-stage osmosis process tank, the electrodialysis process tank, the sand filtration tank, the microfiltration tank, The process of disinfection tank is produced by single or two or more filtration to produce water source (fishery, agricultural water), water source (water source), water source water, concentrated water, desalted water, deboron water, water, mineral desalted water and mineral concentrated water To a system that is capable of performing the same. More particularly, Korean Patent Publication No. 10-073320000 discloses a method for producing mineral water using deep sea water. More specifically, deep sea water is passed through the first reverse osmosis membrane (3), and the first concentrated water (9) Obtaining permeable water (4); Concentrating the first concentrated water (9) by evaporation to obtain a calcium salt (20); Further concentrating the first concentrated water (9) by evaporation to separate the salt (12) and the wastewater (30); Passing the first permeated water (4) through the second reverse osmosis membrane (6) to obtain a second permeated water (8); Obtaining a first mineral solution containing calcium by electrolyzing and replacing chlorine ions from the calcium salt separated from the first concentrated water (9); Obtaining a second mineral solution containing magnesium by electrolyzing the chlorine ions to replace chlorine ions; And mixing the first and second mineral solutions and the second permeated water. Korean Patent Laid-Open Publication No. 10-0992427 discloses a method for producing mineral water from which anions are removed by using a nanofiltration membrane and electrodialysis. First, ions are removed from deep ocean water using a reverse osmosis membrane to obtain concentrated water and desalted water. The mineral concentrated water is evaporated and filtered to obtain a mineral concentrated water in which the calcium salt and the salt are sequentially removed, and then the mineral concentrated water is mixed with the demineralized water to obtain a mineral concentrated diluted water. The mineral concentrated diluted water is then filtered through a Nano Filter ) Membrane to remove anions, and the calcium salt is mixed with demineralized water to obtain mixed dissolution water, and the mixed dissolution water is subjected to electrodialysis to remove anions. In the present invention, the mineral concentrated water is diluted and passed through the NF membrane, and the calcium salt is diluted and electrodialyzed to significantly remove the minerals contained in the mineral concentrated water and the calcium salt, thereby providing the mineral water having improved poultry feeling A technique is disclosed. Korean Patent Laid-Open Publication No. 10-2012-0108402 discloses an MF filtration step; An SWRO step of treating the MF permeated water by reverse osmosis; A BWRO step of treating the SWRO permeate with reverse osmosis; A fresh water intake step of taking BWRO permeated water as fresh water; An NF filtration step of introducing the BWRO concentrated water by the BWRO step into the SWRO step and filtering the concentrated water by the SWRO step with a nanofilter; A low-concentration mineral water intake step of taking NF permeated water with low-concentration mineral water; High-concentration mineral water intake step of taking NF-concentrated water with high-concentration mineral water; Wherein the low-concentration mineral water and the high-concentration mineral water taken in the low-concentration mineral water taking-in step and the high-concentration mineral take-in step are respectively mixed or mixed together to obtain the mineral water from the seawater. . However, when the hardness is higher than 400 mg / L for the purpose of producing high-hardness water from seawater, such prior art technology substantially exceeds the water quality standards of drinking water such as sulfate ion, chlorine ion, boron, and evaporation residue. In addition, the conventional high hardness water producing method is a method of evaporating and concentrating seawater, which consumes a lot of energy. On the other hand, as in the present invention, a system capable of efficiently removing sulfate ions while retaining minerals such as magnesium and calcium by using an ion exchange system is known as a nanofiltration (NF), ion exchange (IX) By using a complex process of the ED system, it is possible to remove sulfuric acid ions as well as chloride ions and to concentrate the useful minerals, such as magnesium and calcium, in order to meet the drinking water quality standard with a high mineral content It differs from a system capable of producing hard water. In addition, while the prior art concentrates the water by evaporating and concentrating the minerals, the cost of production energy is high, while the nano filtration method concentrates the minerals, removes the sulfate ions by the ion exchange system, and removes chlorine ions by the electrodialysis device There is a difference in the structure that can be produced from the system while reducing the energy consumption of the hard water.

Most of the methods of producing high-calorie water through seawater desalination were based on reverse osmosis and evaporation methods. However, the energy consumption was high and sulfate ion, chlorine ion, and evaporation residue were produced, . The basic reason for this is that the evaporation method has a high content of sulfate ion and chlorine ion and is inadequate for the water standard. In addition, the evaporation and concentration method has a disadvantage of consuming a lot of energy. Therefore, the present invention overcomes such problems of the evaporation method as a membrane separation method and an ion exchange method.

In order to solve the above problems, the seawater treatment process of the present invention is as follows.

The present invention relates to a process for producing high-hardness concentrated water using seawater (raw seawater or concentrated water) by NF, removing the monovalent ions (saline) through electrodialysis (ED) And removing the sulfate ions by using a strong basic chloride ion exchange resin (FIG. 1, Example 1).

The ion exchange resin may be cation exchange resin or anion exchange resin depending on the polarity of the ion to be replaced. The amount of the ion exchange resin can be determined according to the concentration and the flow rate of the ion to be replaced.

When the efficacy of the ion exchange resin is lowered, it can be regenerated automatically using salt water, and it can be used according to the regeneration method for each resin type. The principle and method of reproduction are as follows.

a. Wash ionized water with water for 2 hours or more.

b. The regenerator is filled with a ratio of 1/3 of the amount of resin to be used for regenerating the purified water.

c. Add 10% to 15% NaCl to the water and let it melt.

d. Set the ion exchange apparatus to contain 1/10 of the NaCl solution to the water.

e. The longer the playing time, the more effective it is, but it usually takes less than 30 minutes.

Next, as another embodiment of the present invention, seawater (raw seawater or concentrated water) is produced by using desalination equipment such as NF / RO / ED / PRO / FO / And the concentrated water is changed to a step of removing salinity through ED to ion exchange the saline-depleted production water (FIG. 1, Example 2).

Next, as another embodiment of the present invention, concentrated water produced through RO / ED / PRO / FO / MD or the like may be re-evaporated, membrane permeated or electrolyzed by sea water (deep sea water or concentrated water) (Fig. 1, Example 3), and the production water is produced using the desalination equipment having the desalination equipment and the production water is discharged through the desalination equipment.

In addition, it is possible to produce seawater (deep sea water or concentrated water) by ion-exchange by pretreatment of desalination process, and then to produce water and concentrated water by using desalination equipment such as NF / RO / ED / PRO / FO / (Fig. 1 embodiment 4).

In addition, seawater is pretreated with a MF (micro filteration) membrane, and then separated into concentrate seawater and permeate seawater through the NF membrane, And removing the chlorine ions from the NF concentrated water by separating the sodium and chlorine ions from the second concentrated water by charging the second concentrated water into the electrodialysis unit by preserving the hardness component; Wherein the desalted water from which the chlorine ion has been removed is subjected to ion exchange to replace sulfate ions in chlorine ion and desalted water by using a strongly basic chlorine ion resin to remove sulfate ions. Method is provided.

With the existing technology, as the hardness concentration increases, the concentration of chlorine ion and sulfate ion increases so that the concentration of chlorine ion and sulfate ion exceeds 250 mg / L, which is the water quality of water, at hardness higher than 400.

The present invention relates to a method for preparing a high-purity water containing a large amount of minerals through a desalination process using an anion exchange resin so as to satisfy a sulfate ion concentration of 250 mg / L, Minerals hardness components such as calcium ions and magnesium ions are remained, while the mineral hardness component, which is a problem of the conventional desalting method (evaporation method and reverse osmosis method), is increased and the concentration of sulfate ions is also increased, In hard water with hardness of 400 mg / L or more, it is possible to overcome the technical limitations that could not satisfy sulfate and chloride ions in water quality standards.

The system for removing sulfuric acid in seawater using the ion exchange apparatus of the present invention uses a composite method of electrodialysis (ED) and ion exchange (IX) system in a mineral concentrated water in which minerals such as calcium and magnesium are concentrated by a nano filtration method Specific materials such as chlorine ions and sulfate ions can be removed by using an electrodialysis membrane (ED) and an ion exchange system (IX) while remaining selective minerals.

1 shows a system for removing sulfate ions from a seawater using an ion exchange apparatus.
Fig. 2 shows a conceptual view of an ion exchange resin.
Figure 3 shows ion selectivity of Cation (+) ion exchange resin and Anion (-) ion exchange resin.
Figure 4 shows the sulfate ion results of the ion exchange system.
Figure 5 shows the sulfate ion results of the ion exchange system.
Fig. 6 shows the results of sulfate ion after ion exchange.
Fig. 7 shows the hardness results after ion exchange.
Figure 8 shows the sulfate ion results of the ion exchange system.
9 shows the results of the sulfate ion (left: 180 ml / min, right: 600 ml / min) according to the flow velocity change.
Fig. 10 shows the sulfate ion result (left: 265 ml / min, right: 115 ml / min) according to the flow velocity change.
11 shows the sulfate ion result (flow rate: 50 ml / min) according to the NF-ion exchange-ED process change.

I Mineral and Anion Water Quality Characteristics in Deep Ocean Water Treatment Process and Hard Water

1. Characterization of high hardness water and anion water quality

In the present invention, the process of producing deep-sea water treated in the ocean is as follows. The entire process is performed by the deep sea water (raw water) that has been subjected to pretreatment (sand filtration, rapid filtration membrane, MF filter, SMF filter, UF filter, etc.) -dialysis apparatus, the NF tertiary concentrated water through NF (Nano Filtering) is placed in the hardness concentration tank of the ED apparatus, and the electric conductivity of 20 mS / cm is applied to the ED apparatus, A method of producing concentrated deep-sea mineral water with a ratio of (magnesium + calcium) / sodium of 1.0 or more and a mineral content to a sea water is produced in a salt concentration tank and mineral concentrated water is produced in a hardness concentration tank.

During the pretreatment process, sulfate ions (SO ₄ ^{2 -} ) are concentrated in the concentrated water that has not passed through the NF membrane and 50% of the divalent ions such as magnesium and calcium in raw water pass through the NF membrane can not pass through the NF membrane Concentrated in concentrated water. In the concentrated water produced by the NF membrane, magnesium ions and calcium ions, such as divalent ions, pass through the NF membrane, 50% of the NF membrane can not pass through the concentrated water is concentrated, so concentrated NF concentrated water, (NF), calcium and magnesium can produce more mineral-enriched water than raw water.

Conventional reverse osmosis and evaporation techniques are simple, but the ratio of the mineral component ((Ca + Mg) / Na) in the concentrated water is low, and the chloride anion (Cl ^- ), ion (SO ₄ ^2-) was the separation is not a problem. The ED process can raise the concentration of the concentrated water compared to the reverse osmosis and evaporation process, but there is a problem that the sulfate ion (SO ₄ ^2- ) is not removed from the hardness concentration tank.

In order to solve these problems and to increase the production yield, a concentrated water having a salinity concentration of 7% or more is prepared by NF-ED-ion exchange process in combination with NF process and calcium and magnesium are mixed with NF A concentrated mineral water with a relatively high concentration of primary mineral was obtained, and sodium and chlorine ions (Cl ^- ) were removed through an electrodialytic membrane (ED) process and mineral concentrated water with concentrated calcium and magnesium was prepared. -ED- Ion exchange test results are shown.

The quality of the water produced depends on how small the sulfate (SO ₄ ^2- ) is, how much salt is removed, and how much potassium, calcium and magnesium are balanced. By combining NF process, ED process and ion exchange process, it was possible to use minerals with high concentration of sulfur in drastically reduced minerals. Also, by removing chlorine and sulfate ions, It is possible to obtain the effect of reducing the inconvenience of dissolving the magnesium and the like by re-crystallizing and reducing the energy.

NF-ED- Ion exchange component analysis result (unit: mg / l) NF ED Ion Exchange Hardness 20,000 18,274 17,828 Sulfate 19,951 18,479 4,000 Cl ^- 22,282 2,252 12,667

2. Eating Deep sea water  Anion water quality standard

The water quality standards of the drinking water are divided into the criteria for microorganisms, the criteria for harmful health effects, the criteria for inorganic substances in health, the criteria for harmful organic substances, and the criteria for aesthetic effect substances. Dual esthetic influences contain regulating of chloride and sulfate ions. Chloride ion and sulfate ion are the most common anion (more than 99%) in seawater. The standard of water to be consumed is set to 250 mg / L for chlorine ion and 200 mg / L for sulfate ion.

3. From high hardness water Mineral and anion water quality analysis method

Mineral and anion water quality analyzers are shown in the table below. Cations such as sodium, magnesium, calcium and potassium were analyzed by ion chromatography using a cation column IonPac CS12A from Thermoscientific, and anions such as chloride ion and sulfate ion were analyzed by ion chromatographic analysis using anion column IonPac AS14 from Thermoscientific . The concentration of magnesium ion and calcium ion concentration in the deep seawater was calculated by the following formula (Lenore S. C et al., 1998)

Hardness as calcium carbonate (mg / L) = 2.497 x [Ca] + 4.119 x [Mg]

Water quality analysis method Items Analytical instruments and mothed TDS, Conductivity, Salinity, pH METTLER TOLEDO Seven Multi meter Hardness CaCO ₃ calculation Cation:
(Na, Mg, Ca, K) IC (Ion Chromatography)
- model: Cation - ICS-1000, Thermoscientific,
- Cation Column: IonPac CS12A, Anion
(Cl, SO ₄ ^2-) IC (Ion Chromatography)
- model: ICS-1100, Thermoscientific
- Anion Column: IonPac AS14

II. System characteristics of ion exchange unit process and connection process with electrodialysis unit

1. Anion and Mineral Separation Characteristics of Ion Exchange Resins

The ionic water used in the removal of sulfate ion was strongly basic chloride ion with a specific gravity of 1.11 g / mL, exchange capacity of 1.3 meq / mL, effective pH of 0 to 14, and a toys ratio of 95% or more. As shown in FIG. 2, The principle of substitution of chlorine ion in the exchange resin and sulfate ion in the demineralized water was used.

That is, the anions having the same polarity react with each other, and the cations having different polarities are used as the peripheral factors, so that they do not participate in the actual reaction. Using this principle, mineral components such as magnesium, calcium and the like, which are positive ion components, remain, and sulfate ions and chloride ions, which are anion components, actively react and substitute each other. Also, as shown in FIG. 3, it was confirmed that the selectivity of sulfate ion was excellent in the ion selectivity of the ion exchange resin.

2. System Characteristics of Ion Exchange Unit Process

Ion exchange systems are affected by column capacity, the amount of ion exchange resin, flow rate, and concentration conditions.

1) When 300 ml of ionized resin was charged in a 350 ml column volume at a laboratory scale and the flow rate was 66 ml / min, the sulfate ion was reduced to 6 times and there was no change in hardness. (Figure 4)

2) Experiments were carried out at a flow rate of 148 ml / min with 5L of ionized water at a column volume of 8L. The sulfate ion concentration was reduced to 5.6 times and the hardness was not changed. (Fig. 5)

3) When 50L ionic resin was filled in a resin tank tank volume of 60L on a pilot scale and the flow rate was 600 ml / min, the sulfate ion was reduced to 3.7 times as shown in Figs. 6 and 7, . (Fig. 8)

4) It was similar to the result of the above 3) when 500L of ion resin was filled in a resin tank tank volume of 600L in mass production and the experiment was carried out at a flow rate of 6 L / min.

3. Anion removal efficiency of ion exchange unit process

The results of the sulfate ion before and after ion exchange are shown in FIG. The value before ion exchange was 14,500 mg / L and the value after ion exchange was 3,800 mg / L, 3.7 times decreased. The results of hardness before and after ion exchange are shown in Fig. The value before ion exchange was 19,500 mg / L and the value after ion exchange was maintained at 19,800 mg / L.

These results show that when the deep sea water hardness of 1,000 mg / L is diluted about 20 times during manufacturing, the sulfate ion is 190 mg / L, which is suitable to the water quality standard of the drinking water. If the hardness is above 500 mg / L, it will be a case of overcoming the limitation of producing deep-sea water in which the sulfate ion exceeds 250 mg / L.

As a result of the flow rate according to the experimental conditions, the results of the flow rates of 180 ml / min and 600 ml / min are shown in FIG. 9 .

In addition, the results of the flow rate changes of 115 ml / min and 265 ml / min are shown in Fig.

The optimal conditions for the mass production scale were 10 times the pilot scale and the ion exchange resin content was 500L and the flow rate was 6L / min.

As a result, the conditions such as the amount of ion exchange resin and the flow rate can be adjusted according to the respective factors, but the ratio of the ion exchange ion concentration: ion exchange resin amount: flow rate ratio: removal capacity is 20,000 ppm or more, 50 L or more: 600 ml / min or more: 100 kg or more. More specifically, the ion exchange resin amount: flow rate ratio of ion exchange is determined by the ratio of 0.35-50 L: 66-600 ml / min, and the ratio of ion concentration to removal capacity is 20,000 ppm or more: 100 kg or more desirable.

4. Ion exchange - connection with electrodialysis unit

It can be confirmed that the high-hardness concentrated water produced in NF contains a large amount of chloride ion and sulfate ion. Table 2 shows that chlorine ion can be removed by ED and sulfate ion can be removed by ion exchange. In this electrodialysis device, chlorine ion, which is a monovalent anion, was removed by an electrodialysis device in conjunction with ion exchange resin method, and sulfate ion which is a divalent anion which could not be removed by an electrodialysis device could be removed as an ion exchange resin.

In this case, the two processes of NF-ion exchange-ED and NF-ED- ion exchange can be considered as follows. 2-2 is the result of the NF-ED-ion exchange sequence. When the ionic resin was packed into 5 L of the column volume of 8 L and the flow rate was 148 ml / min, the sulfate ion was reduced to 5.6 times, There was no.

Figure 11, on the other hand, shows the results of the NF-ion exchange-ED sequence. Comparing the two results, it can be seen that the NF-ED-ion exchange process is superior to the NF-ion exchange-ED process in the removal rate of sulfuric acid ions, and the NF-ED- ion exchange process is about three times faster It was found that the removal rate of edo sulfate ion was good. This indicates that the concentration of seawater occupies a large part in the efficacy part of the ion exchange resin. Therefore, in this study, experimental design was carried out by NF-ED- ion exchange process.

5. Applicability of ion exchange resin method

1) In the preparation of high-hardness concentrated water used in the experiment, concentrated water from various desalination equipment such as RO / PRO / FO / MD instead of NF can be ion-exchanged after removing salinity through ED.

2) In addition to removing salinity using ED, various desalination equipment such as evaporation method, membrane permeation method and electrolysis method can be used instead, and ion exchange can be performed.

3) Seawater (deep sea water or concentrated water) can be configured to perform ion exchange by pretreatment of desalination process.

4) Depending on the polarity of the ion to be replaced, cation exchange resin or anion exchange resin may be used for the ion exchange resin.

5) The amount of the ion exchange resin in the above 4) can be determined according to the concentration and the flow rate of the ion to be replaced.

6) When the efficacy of the ion exchange resin is lowered, it can be automatically regenerated by using brine, and it can be used according to the regeneration method for each type of resin used.

III . Regeneration method of ion exchange resin

1. Regeneration system configuration of ion exchange resin

After the ion exchange experiment, the automatic regeneration device is connected to the resin tower for the regeneration of the ion resin, and the backwash and regeneration can be performed automatically. The concentration and time of the regeneration liquid can be controlled according to the amount of the ion exchange resin used and the exchange ability. If there is no automatic playback device, you can create the regeneration solution and proceed it manually.

2. Regeneration method of ion exchange resin

When the efficacy of the ion exchange resin deteriorates, it can be automatically regenerated using salt water, and it can be used according to the regeneration method for each resin type. The playback method is as follows.

a. Wash ionized water with water for at least 1 hour.

b. The regenerator is filled with a ratio of 1/3 to the amount of resin to be purified.

c. Add 10% to 15% NaCl to the water and let it melt.

d. Set the ion exchange apparatus to contain 1/10 of the NaCl solution to the water.

e. The longer the playing time, the more effective it is, but it usually takes less than 30 minutes.

3. Regeneration efficiency of ion exchange resin

Ion exchange resin for strongly basic chloride ion is used when the refined salt of refined NaCl content 99% or more is used and the ionized resin is sufficiently backwashed with purified water and when regenerating solution (NaCl) and purified water are used at a constant ratio, However, in consideration of economical efficiency and the like, a regenerating effect of 60% or more is usually used. The limit of regenerated ion exchange resins is 1,000, usually 3 to 5 years.

<Examples>

The process of the system of the present invention for efficiently removing harmful components produced in the desalination process of seawater (deep sea water or concentrated water) can be carried out as follows.

The seawater is pretreated with a MF (micro filteration) membrane and then passed through a NF membrane to separate the concentrate seawater from the permeate seawater. The concentrated water is again fed to the NF membrane To prepare a second concentrated water having a hardness of 20,000 ppm. Removing the chlorine ions from the NF-enriched water by separating the sodium and chlorine ions by storing the hardness component by injecting the second concentrated NF-enriched water into the electrodialysis unit; It is possible to increase the substitution of ions in the ion exchange system by sufficiently removing chlorine ions from the electrodialysis device.

Removing desalted water from the hardness concentrator by using an ion exchange resin; The ion-exchange resin used in the removal of sulfate ion was a strongly basic chloride ion resin, and the principle of substitution of chlorine ion in ion exchange resin and sulfate ion in desalted water was used.

In addition, when it is judged that the effect of the ion exchange resin is lowered, the ion exchange resin used can be automatically regenerated with salt (NaCl) water to improve the economical efficiency.

In another embodiment, high-hardness concentrated water is prepared using seawater (deep sea water or concentrated water) with NF, and the produced high-density concentrated water is subjected to electrodialysis (ED) to remove monovalent ions , And removing the sulfate ions using the strongly basic chloride ion exchange resin (FIG. 1, Example 1).

The ion exchange resin may be cation exchange resin or anion exchange resin depending on the polarity of the ion to be replaced. The amount of the ion exchange resin can be determined according to the concentration and the flow rate of the ion to be replaced.

When the efficacy of the ion exchange resin is lowered, it can be regenerated automatically using salt water, and it can be used according to the regeneration method for each resin type. The principle and method of reproduction are as follows.

a. Wash ionized water with water for 2 hours or more.

b. The regenerator is filled with a ratio of 1/3 of the amount of resin to be used for regenerating the purified water.

c. Add 10% to 15% NaCl to the water and let it melt.

d. Set the ion exchange apparatus to contain 1/10 of the NaCl solution to the water.

e. The longer the playing time, the more effective it is, but it usually takes less than 30 minutes.

Next, as another embodiment of the present invention, seawater (raw seawater or concentrated water) is produced by using desalination equipment such as NF / RO / ED / PRO / FO / And the concentrated water is changed to a step of removing salinity through ED to ion exchange the saline-depleted production water (FIG. 1, Example 2).

Next, as another embodiment of the present invention, concentrated water produced through RO / ED / PRO / FO / MD or the like may be re-evaporated, membrane permeated or electrolyzed by sea water (deep sea water or concentrated water) (Fig. 1, Example 3), and the production water is produced using the desalination equipment having the desalination equipment and the production water is discharged through the desalination equipment.

In addition, it is possible to produce seawater (deep sea water or concentrated water) by ion-exchange by pretreatment of desalination process, and then to produce water and concentrated water by using desalination equipment such as NF / RO / ED / PRO / FO / (Fig. 1 embodiment 4).

By using the NF / IX / ED linkage process, the mineral water content of the seawater desalination process is increased while the sulfate ion and chlorine ion are removed. This high hardness premium can contribute to the public health by providing a manufacturing method of drinking water. In addition, the present invention includes a method for regenerating the ion exchange resin used for the economical use of the ion exchange resin (IX) used, and it is possible to reduce the energy required for manufacturing the mineral high-hardness water, .

Claims (9)

Using seawater (deep sea water or concentrated water) with nanofilter (NF) to produce high-hardness concentrated water;
Removing the univalent ions (saline) through the electrodialysis (ED) of the produced high-hardness concentrated water;
And removing the sulfuric acid ions by ion-exchanging the produced water through the ED. [7] The method for removing sulfate ions in a desalination process
Producing production water and concentrated water by using at least one desalination device selected from NF, Reverse Osmosis (RO), ED, PRO, FO, and MD as seawater (deep sea water or concentrated water);
Wherein the production water is ion-exchanged and the concentrate water is desalted through ED to remove ion-exchanged production water. The ion exchange apparatus for removing sulfuric acid ions
The concentrated water produced by using at least one desalination device selected from RO, ED, PRO, FO, and MD as the seawater (raw seawater or concentrated water) is further subjected to one or more methods selected from an evaporation method, a membrane permeation method, And a step of ion-exchanging the produced water produced through the desalination equipment. The method for removing sulfate ions in the desalination process of seawater using the ion exchange apparatus
Produced water and concentrated water are produced using one or more desalination equipment selected from NF, RO, ED, PRO, FO, and MD after seawater (deep sea water or concentrated water) is ion-exchanged by pretreatment of desalination process A method for removing sulfate ions during a desalination process using an ion exchange apparatus
The ion exchange apparatus according to any one of claims 1 to 4, wherein the ion exchange is replaced by a cation exchange resin or an anion exchange resin depending on the polarity of the ion to be replaced. Ion removal method
5. The method according to any one of claims 1 to 4, wherein the ion exchange resin amount: flow rate ratio of ion exchange is in the range of 0.35 to 50 L: 66 to 600 ml / min. Sulfuric acid ion removal method
The method of claim 6, wherein the concentration of ions in the ion exchange is 20,000 ppm or more, and the removal capacity is set to 100 kg or more.
8. The method according to claim 7, wherein when the efficiency of ion exchange removal capacity is reduced,
a. The ionized resin was washed with water for 2 hours or more,
b. After filling the regenerator with a ratio of 1/3 of the amount of resin to be used for regenerating the purified water,
c. 10% to 15% NaCl was added to the solution,
d. Ion exchanger was set to contain 1/10 of NaCl solution as an integer,
And the regeneration time is set to 30 minutes or less for regeneration. The method for removing sulfate ions during the desalination process
The seawater was pretreated with a MF (micro filteration) membrane, and then passed through a NF membrane to separate it into a concentrate seawater and a permeate seawater.
The concentrated water is again made into a second concentrated water having a hardness of 20,000 ppm by using a NF membrane. The second concentrated water is put into an electrodialysis device to retain hardness components and to separate sodium and chlorine ions, Removing chlorine ions from the solution;
Wherein the desalted water from which the chlorine ion has been removed is subjected to ion exchange to replace sulfate ions in chlorine ion and desalted water by using a strongly basic chlorine ion resin to remove sulfate ions. Way

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