KR100992427B1 - Method for producing mineral water through anion removal by nf membrane and electrodialysis - Google Patents

Abstract

PURPOSE: A manufacturing method of mineral water which removed the anion with a nanofiltration membrane and electrodialysis is provided to remarkably remove the anion included in the mineral water and manufacturing the mineral water which improved the eating feeling, thereby fitting the rate of magnesium and potassium which is useful for the body in optimum state(approximately 3:1). CONSTITUTION: The manufacturing method of mineral water which removed the anion comprised next; a step of obtaining the concentrated water(120) including ion component and desalted water which the ion component is removed by letting a deep sea water to pass through the osmosis membrane; a step of dividing calcium salt crystallization by heat-concentrating and filtering the concentration water to a first evaporator, a step of obtaining the concentration water which salt is removed by heat-concentrating and filtering the concentration water which the calcium crystallization is divided with a second evaporator, a step of obtaining NF permeated water which negative ion with the mineral concentration water to be removed by manufacturing the mineral concentration diluted water as mixing the desalted water and mineral concentration water and enabling the mineral concentration dilute water to the NF having negative ion, a step of obtaining the mixed solution by mixing the calcium salt crystallization with desalted water, a step of obtaining the mineral water by mixing the NF permeated water, the desalted water and the calcium solution.

Description

Method for producing mineral water through anion removal by NF membrane and electrodialysis

The present invention relates to a method for producing mineral water from deep sea water, and in particular, to remove minerals contained in a large amount of mineral concentrated water and calcium salts to prepare mineral water with improved eating sensation, and more specifically, mineral concentration. The water is diluted and passed through the NF membrane, and the calcium salt is diluted by electrodialysis to remove anions.

In general, deep sea water is deeper than 200m deep and does not reach sunlight, and because it does not reach sunlight, it is stable at a lower temperature than the surface, and inorganic nutrients such as nitrates, phosphates, and silicates required for life activities It is a marine resource with characteristics such as rich eutrophicity, low harmful artificial pollutants such as environmental hormones, very few bacteria and organic matters, and ripening aged for a long time at high pressure of 20 atm or higher.

In addition, the deep sea water has a lot of essential trace elements and minerals, and especially the main minerals (magnesium, calcium, potassium) are contained in similar to the ratio of the elemental component of the living body is known to be useful for the production of mineral water through desalination. However, in the case of sea water, membrane filtration or electrodialysis using reverse osmosis membrane, which is a common desalination method, not only removes salt but also removes minerals such as Mg, Ca, and K, which are useful for the human body, or have a problem of unbalanced minerals. have.

Accordingly, the Republic of Korea Patent Publication No. 2009-0061174, as shown in Figure 1, through the deep seawater 10 through the reverse osmosis membrane, the concentrated water 20 including the ionic component and the permeate (30) from which the ionic component is removed Obtaining; Separating the calcium salt (25) crystals by heating and concentrating the concentrated water by using a first concentrator; Heating and concentrating the concentrated water 40 (separated water) from which the calcium salt has been removed using a second concentrator and filtering to obtain a liver water 50 from which the salt 45 is removed; Dissolving the calcium salt (25) in permeate (30) to produce a mixed solution (60), and passing the mixed solution through an anion exchange resin to obtain filtered water (70) from which anions (65) in the mixed solution are removed; And mixing the filtered water (70) passed through the anion exchange resin and the brine (50) to obtain mineral water (80). The manufacturing method is described.

However, the above-described deep ocean mineral water production method is the primary and secondary sulfate worsen a sense of ingestion in order concentrator (SO ₄ ^2-) and chloride ion (Cl ^-), but to remove the anions, such as getting the guard 50 , The still water 50 is still contained in a large amount of negative ions, and because of this, the mineral water thus prepared still has a bad eating feeling.

Accordingly, an object of the present invention is to provide a method that can significantly reduce the anion, especially sulfate ions contained in a large amount of mineral concentrated water (salt water), to produce a mineral water with improved eating feeling.

In addition, the present invention is to provide a mineral water containing magnesium (Mg ²⁺ ) and potassium (K ⁺ ), which are useful for the human body with anion removal, in an optimally suitable ratio (about 3: 1) for the human body.

In addition, the present invention is to provide a method that can be used in the production of mineral water only after removing the anion to reduce the eating odor from the calcium salt separated during the mineral concentrate production process, increasing the soft eating sensation.

The present invention for achieving the above object, the step of passing the deep sea water through the reverse osmosis membrane, to obtain a concentrated water containing the ionic component and demineralized water from which the ionic component is removed; Heating and concentrating the concentrated water with a first evaporator to separate calcium salt crystals; Heating and concentrating the concentrated water from which the calcium salt crystals are separated by a second evaporator to obtain mineral concentrated water from which salts are removed; The demineralized water and the mineral concentrated water are mixed to prepare a mineral concentrated dilution water, and the mineral concentrated dilution water is passed through a nano-filter (NF) membrane having a negative ion. Obtaining the removed NF permeate; Mixing the calcium salt crystals with demineralized water to obtain mixed dissolved water, and electrolyzing the mixed dissolved water to obtain calcium dissolved water from which anions are removed; And mixing the NF permeated water with demineralized water and dissolved calcium water to obtain mineral water, wherein the anion is removed by nanofiltration membrane and electrodialysis.

Here, the electrodialysis may be made by applying a voltage of 30 ~ 50 Volts.

The nanofiltration membrane (NF membrane) is preferably formed with a negative (-) ion on the surface.

In addition, the preparation of the mineral concentrated dilution water, it is possible to produce a mixture of more demineralized water in a weight ratio of 1: 1 or more of the demineralized water and mineral concentrated water.

Specific details of other embodiments are included in the detailed description and the drawings.

According to the present invention, by passing the mineral concentrate water through a nano filtration (Nano Filter) membrane, by significantly removing the anions contained in the mineral concentrate water, it is effective to produce a mineral water with improved eating feeling have.

In addition, the present invention does not pass the mineral concentrated water through the NF membrane as it is, in particular by mixing the mineral concentrated water with demineralized water in a specific ratio to obtain mineral concentrated dilution water, and then passing the mineral concentrated dilution water through the NF membrane, Along with the removal of anions, the ratio of magnesium (Mg ²⁺ ) and potassium (K ⁺ ), which are useful to the human body, can be adjusted to an optimal state (about 3: 1).

In addition, the present invention by diluting the calcium salt separated in the process of producing mineral concentrate water to remove the anion to reduce the feeling of eating by electrodialysis, thereby providing a method that can only use calcium ions to increase the soft eating feeling in the preparation of mineral water can do.

Hereinafter, one preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

Figure 2 is a flow chart illustrating a method for producing a mineral water from which anions are removed by nanofiltration membrane and electrodialysis according to the present invention. As shown here, the present invention relates to a method for producing mineral water containing mineral components (Mg, K, Ca, etc.) useful for the human body using deep sea water.

The overall process of the present invention may first undergo a pretreatment process in which the deep seawater 110 is pretreated with MF (fine filtration membrane) and / or UF (ultrafiltration membrane) to remove insoluble components and organic matter in the deep water. Then, the pretreated deep water 110 is passed through a reverse osmosis membrane (RO membrane) to obtain a concentrated water 120 including the ionic component and demineralized water 130 from which the ionic component is removed. Subsequently, the concentrated water 120 is subjected to a vacuum concentration process by MED (multi-utility method) and TVR (thermal steam recompression method) to separate and crystallize calcium salt 125 and sodium chloride 145. The present invention specifically mixes the mineral concentrated water (150, brine) thus left with the demineralized water (130) to produce mineral concentrated dilution water (170), which is passed through NF (175, nano-separation membrane) to produce anions (sulphate ions). : Characterized by removing SO ₄ ^2- , chlorine ion: Cl ⁻ ). In addition to this, the calcium salt 125 is mixed with demineralized water 130 to increase its solubility, thereby obtaining mixed dissolved water 160 in which calcium salt is dissolved (for example, calcium sulfate dissolved water), and electrodialysis ( The ED (group 165) is used to separate anions (eg, sulfate ions) from the mixed dissolved water 160 to obtain calcium dissolved water 166. The present invention is to prepare the mineral water by mixing the deionized water (130) according to the mineral composition ratio of NF permeated water 180 and calcium dissolved water (166) from which the anion has been removed as described above.

Specifically, the present invention, before permeating the deep seawater 110 to the reverse osmosis membrane, in order to remove the suspended solids and organic matter present in the deep seawater 110, MF (precision membrane) and / or UF (ultraviolet) The pretreatment process may be performed using a pretreatment membrane composed of a filtration membrane. Both the microfiltration membrane and the ultrafiltration membrane are filtered according to the molecular size or the types of substances that can be filtered depending on the molecular size. Usually the pore size of the microfiltration membrane is about 0.1 ~ 10μm and the filterable materials are suspensions and suspended solids. In addition, in the case of the ultrafiltration membrane, the pore size is about 20 ~ 1000A is the size that can filter to bacteria and yeast. By going through this pretreatment process, the reverse osmosis membrane can be protected and the recovery rate can be kept constant.

The present invention passes the deep water 110 subjected to the pretreatment through the reverse osmosis membrane to obtain a concentrated water 120 including the ionic component and demineralized water 130 from which the ionic component is removed. For example, the deep water 110 is permeated through a reverse osmosis membrane (RO membrane) at a pressure of 50 to 60 kg / cm ³ to prepare primary demineralized water and primary concentrated water 120. Secondary demineralized water 130 and secondary concentrated water may be obtained by passing the first demineralized water through the reverse osmosis membrane (RO membrane). Here, the secondary concentrated water can be recycled to the deep sea water 110 by the cooling crystal tube during the decontamination process.

The concentrated water 120 is concentrated by heating with a first evaporator and filtered to separate the calcium salt 125 crystals, and the concentrated separated water 140 in which the calcium salt 125 crystals are separated by a second evaporator is heated to concentrate. And filtering to obtain the mineral concentrated water 150 from which the salt 145 has been removed. Since each of the minerals contained in the deep sea water 110 has its own solubility, by adjusting the specific gravity through the vacuum concentration process, it is possible to extract each of the minerals according to their solubility. As shown in Table 1 below, by applying heat to the concentrated water 120 to evaporate, it can be seen that the amount of precipitated minerals varies as the specific gravity of the concentrated water 120 is adjusted. First of all, a small amount of Fe ₂ O ₃ is precipitated, and then all Ca salts (CaCO ₃ and CaSO ₄ ) and NaCl, MgCl ₂ , MgSO ₄ , KCl contained in the deep water 110 are sequentially or simultaneously. Precipitates.

[Table 1: Precipitation (g / L) during evaporation of seawater]

Specific gravity (Be) Volume (cc) Fe ₂ O ₃ CaCO ₃ CaSO ₄ MgSO ₄ MgCl ₂ NaCl NaBr KCl 3.4 1000 7.1 533 0.003 0.0642 11.5 316 Trace 14.0 245 Trace 16.75 190 0.0550 0.5600 20.60 145.5 0.5620 22.00 131.0 0.1480 25.00 112.0 0.1600 26.25 95.0 0.1508 0.0040 0.0078 3.2614 27.00 64.0 0.1476 0.0130 0.0356 9.6500 28.50 39.0 0.0700 0.0260 0.0444 7.8960 0.0728 32.30 30.0 0.0144 0.0174 0.0150 2.6240 0.0358 32.40 23.0 0.0254 0.0240 2.2720 0.0518 35.0 16.2 0.5382 0.0274 1.4040 0.0620 Total precipitation 0.0030 0.1172 1.7488 0.6240 0.1532 27.1074 0.2224 Mineral concentrate
Remaining amount 1.8548 3.1640 0.5885 0.3300 0.5335 Sum 0.0030 0.1172 1.7488 2.4788 3.3172 27.695 0.5524 0.5335

In the present invention, in concentrating and filtering the concentrated water 120 in this manner, CaSO ₄ is applied to the concentrated water 120 by applying a vacuum concentration process consisting of MED (multiple application method) and TVR (thermal steam recompression method). And NaCl. Currently, there are several methods of vacuum concentration. MSF (multi-stage evaporation method) that converts seawater into steam after condensation by flashing to release steam instantly, and evaporation by latent heat exchange between steam condensing inside pipe and concentrated brine flowing out of the pipe and lowering pressure in the container There is a method such as MED (multiple utility). In particular, MED has the advantage of allowing evaporation without additional effects after the first steam injection. According to the present invention, in addition to the MED method, a TVR (thermal vapor recompression method) is installed and a portion of the steam generated in the low pressure effect is sucked into the high pressure steam, mixed with high pressure steam, and compressed. By recycling this heat, the efficiency was further increased.

In the multi-effect vacuum evaporation method according to the present invention, the steam generated in the first evaporator boiler acts as a heating source of the next utility evaporator, becomes a condensed water by cooling condensation, and becomes fresh water, and the steam generated in the second evaporator. Is the next source of heat in the evaporator to evaporate the concentrated water inside the evaporator. At this time, it is possible to reduce the energy required to evaporate the concentrated water by lowering the boiling point by vacuum reduced pressure, in the present invention used a TVR (thermal vapor recompression method) method in a more improved manner. In the TVR (Heat Steam Recompression Method), the high-pressure steam through the first stage evaporator is converted to low pressure steam, which maximizes energy efficiency by reusing the steam that has been recompressed through the heat ejector. .

In the energy sector, MSF (Stage Evaporation) requires about 126 х 10 ⁵ to 144 х 10 ⁵ J to produce one tonne of fresh water, whereas for MED-TVR it is about 54 х 10 ⁵ to 72 х 10 ⁵ J. Energy is needed. Comparing the above values, MED-TVR can achieve energy efficiency of about 2.3 times compared to MSF. Also, GOR (Evaporator's performance indicator indicating the amount of evaporator when steam is added, Kg) When comparing freshwater / Kg steam), MSF is about 8 ~ 12 and MED-TVR is about 12 ~ 16.

The calcium salt (CaSO ₄ ) crystals produced during the vacuum concentration process contain calcium, which is an important component useful for the human body, and the present invention relates to NF permeated water 180 and demineralized water 130 which will be described below. Mixing may produce mineral water.

Subsequently, in the present invention, the demineralized water 130 and the mineral concentrated water 150 are mixed to prepare a mineral concentrated dilution water 170, and the mineral concentrated dilution water (NF) membrane 175 is formed on the membrane. Passing through 170 to obtain NF permeated water 180 from which anions (sulfate ions: SO ₄ ^2- , chlorine ions: Cl ⁻ ) in the mineral concentrated dilution water 170 are removed.

According to the prior art, as shown in Figure 1, by mixing the mineral concentrated water (50) obtained by separating the anion with the primary and secondary concentrator in the filtered water (70) passed through the anion exchange resin to produce mineral water have. In this case, however, the mineral concentrate 50 obtained by separating anions with a concentrator still contains a large amount of anions, and thus, the mineral water thus prepared still had a poor eating habit.

Experimental results of the present inventors, as can be seen in the examples described later, by separating the anions than the amount of sulfate ions (SO ₄ ^2- ) (5,404mg / L) contained in the primary concentrated water 20 In the mineral concentrate 50 obtained, a significant amount (37,852 mg / L) of sulfate ions (SO ₄ ^2- ) was included, and the inventors of the present invention concentrated the mineral concentrate 150 in demineralized water 130 to solve this problem. Mixing with to obtain a mineral concentrated dilution water 170, it was passed through the NF film 175 to significantly reduce the negative ions.

The NF membrane 175 is generally one of the pretreatment membranes used in the pretreatment of raw water, but the present inventors apply it to the mineral concentrate 150 to remove anions, and to pass the NF membrane 175 to this purpose. Previously, the mineral concentrated water 150 was mixed with the demineralized water 130 to obtain the mineral concentrated dilution water 170, which was then passed through the NF film 175. As described above, the mineral concentrated water 150 is mixed with the demineralized water 130 to obtain the mineral concentrated dilution water 170, but there is also a function for preventing the NF film 175 having a fine size hole from being blocked. This is because when the mineral enriched dilution water 170 passes through the NF membrane 175, the ratio of Mg and K, which are useful to the human body, along with anion removal can be adjusted closer to the ideal 3: 1. The ratio of mixing the demineralized water 130 and the mineral concentrated water 150 is preferably 4: 1 or more, and in particular, the present inventors have a weight ratio of the demineralized water 130 and the mineral concentrated water 150 to 6: 1 or 7: 1 or more. It was confirmed that it is most preferable to mix and prepare more demineralized water.

In addition, the present invention used the NF membrane 175 to remove the negative ions contained in the mineral concentrated dilution water 170, the NF membrane 175 basically does not separate the ions by the action of electrical force The anion contained in the mineral concentrated dilution water 170 is separated by physical pressure. In particular, in the present invention, by using the NF film 175 having a negative ion, the negative ions contained in the NF film 175 are electrically charged to the negative ions contained in the mineral concentrated dilution water 170. By pushing the repulsive force so as not to pass through the NF film 175, only the anion (sulfate ion and chlorine ion) was removed and the cation (magnesium and potassium) contained NF permeated water 180. For this purpose, it is preferable that the surface of the NF film 175 is treated with a negative ion, and a negative ion is formed on the surface thereof.

The present inventors also considered using a conventional anion exchange resin in order to remove anions from the mineral concentrate water 150, but an anion exchange resin is an exchanger such as an amine group, an ammonium group, and the like to remove anions originally. It is contained in the form of granules, which is not suitable for removing the anion to the highly concentrated mineral concentrated water 150. In addition, the anion exchange resin had to be added to the regenerant separately in order to remove the negative ions trapped therein, there was a disadvantage in that the exchanger and the like included in the granular form to be replaced at regular intervals.

In addition, the present invention is obtained by mixing the calcium salt (125) crystals with demineralized water 130 to obtain a mixed dissolved water 160, the mixed dissolved water 160 by electrodialysis (165) to remove the anion calcium dissolved water Characterized in that the step (166) to obtain.

This is by diluting the calcium salt 125 separated in the process of producing mineral concentrate 150 and removing anion (for example, sulfate ion (SO ₄ ^2- )) which reduces the eating sensation by electrodialysis (165) method. In addition, only calcium ions (Ca ²⁺ ), which increase soft eating, are used for the preparation of mineral water.

In general, in Japan, OI (O Index, water taste index) defines the delicious water conditions, where the delicious water conditions here are more Ca (calcium), K (potassium), SiO ₂ (silicon dioxide) and Mg ( Magnesium), SO ₄ (sulfuric acid) is less the water taste is excellent. In the case of calcium and potassium, the water taste is softened to improve the taste, and in the case of sulfuric acid, it not only gives a bitter taste, but also combines with calcium to reduce calcium.

In the present invention, in order to selectively remove the sulfate ions that worsen the taste of water, in the mineral water manufacturing process, the sulfuric acid ions in the calcium dissolved water (166) and the NF permeated water (180), which is a part of the mineral inflow, and the NF process. Each of the ED (electrodialysis) was removed to improve the taste of water.

In the ED (electrodialysis) group 165 used in the present invention, an anode and a cathode are installed at both ends thereof, and an anion permeable membrane and a cationic permeable membrane are intersected therebetween, and when a voltage is supplied to both electrodes, the cation and the anion are removed. A device capable of doing this was used. That is, the anion moves through the anion permeable membrane toward the anode and the cation moves through the cation permeable membrane toward the cathode to separate the cation and the anion contained in the mixed dissolved water 160. Thus, in the case of mixed dissolved water 160 according to the invention, for example CaSO ₄ (calcium sulfate) dissolved water, Ca ⁺ (calcium) ions pass through the cation permeable membrane and SO ₄ ^2- (sulfate) ions are anions By passing through the permeable membrane to the anode to selectively remove sulfate ions and the like, calcium dissolved water 166 containing only calcium ions can be obtained.

Then, the present invention is to mix the NF permeated water 180 and demineralized water 130 and calcium dissolved water 166 obtained as described above, to prepare a mineral water.

That is, the NF permeated water 180 contains Mg and K (in a ratio of about 3: 1), and magnesium is dissolved in the state of MgCl ₂ (magnesium chloride) and MgSO ₄ (magnesium sulfate). , Potassium is present in the form of KCl (potassium chloride). In addition, the calcium dissolved water 166 is removed from the SO ₄ ^2- (sulfuric acid) ion to reduce the water taste, and contains only Ca ⁺ (calcium) ion to increase the water taste.

Thus, in the present invention, the NF permeated water 180, the calcium dissolved water 166 and the demineralized water 130 may be mixed to prepare mineral water similar to the mineral ratio of the human body.

The key to mineral water production is to extract only the minerals that are beneficial to your body, eliminating the water-inhibiting ingredients, and mixing the extracted minerals in a similar proportion to the minerals in your body. In the present invention, the ratio of magnesium and potassium, which are beneficial to the body, is controlled to be similar to the mineral ratio of the human body through the manufacturing process of mineral concentrated dilution water (170), and anion, which is a component that inhibits water taste through NF (nano filter) process. Was selectively removed, and calcium salt was diluted to electrodialyze so that only Ca ⁺ (calcium) ion was included without SO ₄ ^2- (sulfuric acid) ion.

The invention may be better understood by the following examples, which are intended for purposes of illustration of the invention and are not intended to limit the scope of protection defined by the appended claims.

Example 1 Concentration and Desalination of Deep Sea Water Through RO Process

Depth of deep ocean water is treated with two stages of pretreatment consisting of a micro filter with a pore size of 0.5 μm and a micro filter of 1 μm (Material: Polyvinylidene fluoride (PVDF)), followed by a primary RO membrane (Material: Poolyamide (PA)). Company: Woongjin Chemical) to obtain primary concentrated water and primary demineralized water. Then, the first demineralized water was transferred to a second RO membrane (material: Polyamide (PA), manufacturer: Woongjin Chemical) to separate the second demineralized water and the second concentrated water. The mineral concentrations contained in the raw water (deep water), pretreated water, demineralized water, and concentrated water in each process are shown in Table 2 below.

[Table 2: Mineral concentrations in raw water (deep water), demineralized water and concentrated water]

division Deep water Pretreatment water Primary concentrated water Primary demineralized water 2nd demineralized water Na (mg / L) 10,800 10,800 20,572 35 0.3 Mg (mg / L) 1,300 1,300 2,479 One 0 Ca (mg / L) 456 456 870 0.3 0 K (mg / L) 414 414 789 1.3 0 SO4 (mg / L) 2,833 2,833 5,404 One 0 Cl (mg / L) 22,370 22,370 42,625 56 0.4 B (mg / L) 5.12 5.12 8.1 0.42 0.27

As shown in Table 2, when comparing the mineral concentration of the deep water and the pre-treated water as raw water, the mineral content did not change, and in the case of secondary demineralized water, the content of all minerals including sodium (Na) was removed by 99% or more. In the first concentrated water, all the minerals were concentrated about twice as much as the raw water, among which sulfate ions (SO ₄ ^2- ) contained 5,404 mg / l.

Example 2 Separation of Calcium Salts and Salts Using MED-TVR (Multi-Effect Vacuum Evaporation Method-Thermal Steam Recompression Method)

The primary concentrated water obtained in Example 1 was concentrated by heating in a first evaporator until the specific gravity of about 24 to 25 ° Be by vacuum concentration method to precipitate CaSO ₄ . And the remaining filtrate was transferred to the second evaporator, and the second evaporator concentrated the remaining filtrate until the specific gravity of about 32.5 ~ 35 ° Be precipitated NaCl, when the NaCl precipitated contained in the remaining filtrate and NaCl precipitate Mineral concentrate (mineral concentrate) was separated using a centrifuge.

Example 3: Preparation of NF Permeate Using Dilute Mineral Concentrated Water and NF Membrane (Nano Filter)

The mineral concentrated water separated in Example 2 was mixed with secondary demineralized water obtained in Example 1 to prepare mineral concentrated dilution water. The mixing ratio of mineral concentrated water and secondary demineralized water is as shown in Table 3 below. Table 3 below shows the mineral content of the mineral concentrated dilution water mixed according to the mineral concentration number and ratio.

As shown in Table 3, the mineral concentrated water contained 37,852 mg / L of sulfate ion (SO ₄ ^2- ), which was included in the primary concentrated water 20 (SO ₄ ^2- ). It can be seen that the amount is significantly more than the amount (5,404mg / ℓ).

Table 3: Mineral Content of Mineral Concentrated Water and Mineral Concentrated Dilution Water]

division Na (mg / L) Mg (mg / L) Ca (mg / L) K (mg / L) SO ₄ (mg / L) Cl (mg / L) Mineral concentrate 22630 67428 0 20136 37852 269578
Demineralized water: Mineral concentrated water 4: 1 4316 13060 0 4044 7428 42378 5: 1 3521 10883 0 3370 6190 35315 6: 1 3157 9329 0 2889 5306 30270 7: 1 2698 8163 0 2528 4643 26486

Then, the mineral concentrated dilution water mixed with the demineralized water and the mineral concentrated water in the ratio of 4: 1 to 7: 1 was passed through the NF membrane containing anion to obtain NF permeated water. As the NF film used in this example, a nano filter (Woongjin Chemical, NE-4040-70) in which the membrane surface was treated with anion was used. The mineral content contained in the ratio-enriched NF water thus obtained is as shown in Table 4 below.

Table 4: Mineral Content of NF Permeate

division Na (mg / L) Mg (mg / L) Ca (mg / L) K (mg / L) SO ₄ (mg / L) Cl (mg / L)
Demineralized water: Mineral concentrated water 4: 1 4601 10849 N.D. 4463 1162 39079 5: 1 3109 8620 N.D. 3602 1218 30175 6: 1 3009 6888 N.D. 2836 1196 24271 7: 1 2124 6916 N.D. 2595 1135 26783

That is, Table 3 is the mineral content contained in the mineral concentrated dilution water before the NF membrane permeation, Table 4 is the mineral content contained in the NF permeate water after the NF membrane permeation. As shown in Table 3 and Table 4, the content of Cl and SO ₄ was significantly reduced before and after the permeation of the NF membrane, in particular, the content of SO ₄ can be confirmed that up to 80% or more removed compared to before and after the NF membrane permeation. This is believed to be the result of the greater removal of sulfate ions having a higher molecular weight by anions formed on the surface of the NF film.

In addition, the ratios of magnesium (Mg) and potassium (K) in NF permeated water for mineral concentrated dilution waters with a ratio of 4: 1, 5: 1, and 6: 1 of demineralized water and mineral concentrated water were 2.43: 1, 2.39, respectively. : 1 and 2.43: 1, but the ratio of magnesium (Mg) and potassium (K) in the NF permeate to mineral concentrated dilution water with the ratio of desalted water and mineral concentrated water is 7: 1, which is 2.67. It can be seen that similarity.

Example 4 Calcium Dissolved Water Preparation by Electrodialysis

The calcium sulfate (CaSO ₄ ) salt precipitated according to Example 2 was mixed with the secondary demineralized water of Example 1 to prepare calcium sulfate dissolved water, which was then placed in an electrodialysis machine, and the voltage of 40V in the electrodialysis machine. A constant current was sent through to separate Ca ²⁺ (calcium ions) and SO ₄ ^2- (sulfate ions). Table 2 shows the change in the content of calcium and sulfate ions over time after electrodialysis.

[Table 5: Contents of Calcium Ion and Sulfate Ion by Electrodialysis from Calcium Sulfate Dissolved Water to Calcium Dissolved Water]

Mineral content
Operating time (min) Ca (mg / L) SO ₄ (mg / L) Voltage (V) Early 0 725 40 60 2 692 40 120 86 319 40 180 150 117 40 240 295 40 40

As shown in Table 5, by the electrodialysis according to the present invention it was possible to obtain a calcium dissolved water finally removed about 95% sulfate ions.

Example 5 Preparation of Mineral Water Using Ca Dissolved Water and NF Permeated Water

Secondary demineralized water according to Example 1, NF permeated water according to Example 3, and calcium dissolved water according to Example 4 were mixed in an appropriate amount to prepare mineral water having a balanced mineral balance.

Since the ratio of magnesium (Mg) and potassium (K) in the NF permeated water according to the present invention is about 3: 1, and the calcium dissolved water contains calcium (Ca), calcium dissolved water is properly mixed with the NF permeated water. By doing so, the content of calcium ions can be freely controlled.

Thus, the present invention was able to produce a mineral water excellent in water taste, the sulfate ion that inhibits the water taste is reduced and the calcium ion that improves the water taste is increased.

On the other hand, while the present invention has been shown and described with respect to certain preferred embodiments, the invention is variously modified and modified without departing from the technical features or fields of the invention provided by the claims below It will be apparent to those skilled in the art that such changes can be made.

The present invention can significantly remove the negative ions contained in the mineral concentrated water and calcium salt in a large amount, it is possible to provide a mineral water with improved eating feeling.

1 is a flow chart for explaining a deep seawater mineral water manufacturing method for improving the eating feeling through the adjustment of mineral components and ion exchange according to the prior art,

Figure 2 is a flow chart illustrating a method for producing a mineral water from which anions are removed by nanofiltration membrane and electrodialysis according to the present invention.

Claims (4)

Passing the deep ocean water through a reverse osmosis membrane to obtain concentrated water containing ionic components and demineralized water from which ionic components have been removed; Heating and concentrating the concentrated water with a first evaporator to separate calcium salt crystals; Heating and concentrating the concentrated water from which the calcium salt crystals are separated by a second evaporator to obtain mineral concentrated water from which salts are removed; The demineralized water and the mineral concentrated water are mixed to prepare a mineral concentrated dilution water, and the mineral concentrated dilution water is passed through a nano-filter (NF) membrane having a negative ion. Obtaining the removed NF permeate; Mixing the calcium salt crystals with demineralized water to obtain mixed dissolved water, and electrolyzing the mixed dissolved water to obtain calcium dissolved water from which anions are removed; And Mixing the NF permeated water, demineralized water and calcium dissolved water, to obtain a mineral water, the method of producing a mineral water from which anion is removed by nanofiltration membrane and electrodialysis. The method of claim 1, wherein the electrodialysis is performed by applying a voltage of 35 to 45 volts (Volt). The method of claim 1, wherein the nanofiltration membrane (NF membrane) has negative ions formed on a surface thereof, and the anion is removed from the nanofiltration membrane and electrodialysis. The method of claim 1, wherein the preparation of the mineral concentrated dilution water, The method of producing mineral water from which anion is removed by nanofiltration membrane and electrodialysis, wherein the demineralized water and the mineral concentrated water are mixed with more demineralized water in a weight ratio of 7: 1 or more.

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