KR100686979B1 - Manufacturing method of a high purity clean-salt from deep sea water - Google Patents

Abstract

A method of manufacturing high-purity salt from deep sea water by several processes comprising heating, filtering, pH adjusting, reverse osmosis filtering, neutralizing, electro-dialyzing, evaporating, dehydrating and drying treatment is provided. The salt is high in cleanness and rich in nutrient as compared to sea salt and can be widely used as table salt. The high-purity salt is prepared by the steps of: heating deep sea water at 20 to 30deg.C and pretreating by nano-filtration; adjusting the pH of the deep sea water to 4.5 to 6.5 and subjecting to reverse osmosis concentration to give desalinated water which is sent to a drink making process and a concentrated brine solution which is sent to a nano-filtration process; sending mineral components from the nano-filtration to a mineral making process and the brine solution to a neutralization tank; supplying 5 to 10% by weight of alkali to the brine solution and subjecting to desalting treatment by applying direct current and sending to a mineral making process; subjecting the concentrated brine to electro dialysis and sending to an evaporation tower to allow counterflow contact with hot air; and dehydrating and drying deposited salt.

Description

Manufacturing method of a high purity clean-salt from deep sea water}

1 is an overall process of manufacturing clean salt from deep sea water

Figure 2 is a concentrated brine production process by neutralization and electrodialysis

3 is a process diagram for evaporation and magnetization, salt precipitation and dehydration

Figure 4 is a precipitation rate of various salts according to the change in specific gravity of the deep sea water at 80 ℃

5 is a change in concentration of the salt contained by the concentration of deep sea water

Fig. 6 is a relational chart of precipitation amount of salts in the deep sea water concentration process.

7 is a change in concentration of the salt contained in the electrodialysis process

8 is a relational diagram of seawater, water, and a lake

<Explanation of symbols for main parts of drawing>

 1: electrodialysis apparatus 2: anion exchange membrane

 3: cation exchange membrane 4: anode chamber

 5: cathode chamber 6: desalting chamber

 7: salt concentration room 8: anode

 9: cathode 10: rectifier

11: China 12: Chinese Agitator

13: brine transfer pump 14: concentrated brine reservoir

15: concentrated brine transfer pump 16: salt extraction tank

17: salt salt tank Rake 18: return water storage tank

19: return pump 20: magnetizer

21: Evaporation Tower 22: Spray Nozzle

23: Demister 24: Blower

25: burner 26: heat exchanger

27: precipitate conveyer (screw conveyer)

28: dehydration liquid storage tank 29: dehydration liquid feed pump

pH: hydrogen ion concentration N: N-Pole S: S-Pole

Ⓢ: Solenoid valve M: Motor

BI: Baume indicator

BIS: Baume indicating switch

TIC: Temperature indicating controller

ECIS: Electric conductivity indicating switch

The present invention relates to a method for producing clean salt, and more particularly, to collect deep sea water, perform nanofiltration and reverse osmosis, and then concentrate the salt (NaCl) by electrodialysis to evaporate and magnetize. When the salt is precipitated while dehydrating and drying relates to a method for producing a high purity clean salt.

Deep sea water has a higher concentration of nutrients, such as low temperature, low temperature, phosphoric acid, silicon, and nitrate nitrogen, as compared to surface water, as shown in Table 1 below. It has low concentrations of environmental pollutants, suspended solids and suspended solids, and low concentration of microorganisms.

             Table 1 Analysis table of deep seawater and surface seawater

    Classification         Item    Deep sea water    Surface layer seawater    General Item   Water temperature （℃）     0-12    16.5-24.0   pH acidity      7.98     8.15   DO dissolved oxygen (mg / ℓ)      7.80     8.91   TOC Organic Carbon (mg / ℓ)      0.962     1.780   Soluble Evaporation Residue (mg / ℓ)   40750 37590   M-alkalido (mg / l)     114.7   110.5       Main element   Cl-chloride (%)       2.237     2.192   Na sodium (%)       1.080     1.030   Mg Magnesium (%)       0.130     0.131   Ca calcium (mg / ℓ)     456   441   K potassium (mg / ℓ)     414   399   Br bromine (mg / ℓ)      68.8    68.1   Sr Strontium (mg / ℓ)       7.77     7.61   B boron (mg / ℓ)       4.44     4.48   Ba barium (mg / ℓ)       0.044     0.025   F Fluorine (mg / ℓ)       0.53     0.56 _{^{SO 4 2 - (mg / ℓ}} )    2833  2627    Nutrient salts NH ₄ ⁺ ammonia nitrogen (mg / l)       0.05     0.03 NO ₃ ^- Nitrogen Nitrate (mg / ℓ)       1.158     0.081 PO ₄ ^{3 -} phosphate (mg / ℓ)       0.177     0.028   Si silicon (mg / ℓ)       1.89     0.32     Trace element   Pb lead (μg / ℓ)       0.102     0.087   Cd Cadmium (μg / ℓ)       0.028     0.008   Cu copper (μg / ℓ)       0.153     0.272   Fe iron (μg / ℓ)       0.217     0.355   Mn manganese (μg / ℓ)       0.265     0.313   Ni nickel (μg / ℓ)       0.387     0.496   Zn Zinc (μg / ℓ)       0.624     0.452   As Arsenic (μg / ℓ)       1.051     0.440   Mo molybdenum (μg / ℓ)       5.095     5.555    Number of bacteria   Viable count (pcs / mℓ) 10 ² 10 ^{4 3-10}

Note) The analysis table in Table 1 is a numerical analysis of the deep seawater and surface seawater at 374m below the east of Muroro Lighthouse, Muro City, Koji Prefecture, Japan.

In addition, the deep ocean water contains various essential trace elements necessary for the human body, and has a characteristic that the cluster of water molecules is matured as microclustered water under high pressure for a long time.

The number of groups of water molecules in deep ocean water is 70-80 Hz for the value of ¹⁷ O-NMR half width of Nuclear magnetic resonance, and 70-80 values for the half-width of ¹⁷ O-NMR value. As for the number of water molecule population of 80 microseconds, 7-8 water molecules corresponding to 1/10 of the value of ¹⁷ O-NMR half width | variety are clustered by mutual hydrogen bond.

Considering the considerations when preparing the salt by taking deep ocean water is as follows.

① Bromine (Br) and boron (B) harmful to human body should be removed as much as possible.

(2) In the brine concentrated reverse osmosis process, membrane clogging due to scale generation during operation may cause fouling, resulting in an increase in pressure loss coefficient, drift of feed water, and deterioration of reverse osmosis membrane. You must drive.

③ Various mineral components are magnetized and treated with activated salts to produce activated salts with improved absorption efficiency.

Conventional salt production methods in deep sea water use Japanese Patent Application Laid-open No. Hei 10-150947, where the production time is long when concentrated brine is produced at room temperature without heating. As it grows larger, there is a problem in that salt production is restricted depending on weather and weather conditions.

In addition, in the conventional salt preparation method, a reasonable amount of healthy salt is removed, which is known as a carcinogen (Br) and boron (硼 素: B), which is known to cause a disorder of the digestive or nervous system of the human body when a large amount is ingested for a long time. The production method has not been proposed yet.

In the present invention, the Bomedo (° Be) of the Baume's hydrometer representing the specific gravity of the seawater is expressed as a numerical value of the scale when the Bomeviometer floated on the liquid to measure the specific gravity of the liquid, the heavy liquid heavier than the specific gravity of the water Heavy bomedoes of the dragon and light bomedoes of the light liquids which are lighter than the specific gravity of water are used. Among these, the heavy liquids have a pure water of 0 °. Be, 15% saline solution at 15 ° Be, and 15 divisions in between. The liquid solution is 10% saline solution at 0 ° Be, and pure water is 10 ° Be. The scale is divided into 15 equal parts, and the bomedo (° Be) is widely used as a measure of concentration because it approximates the salt concentration (wt%) in seawater.

The relationship between the Bume (° Be) and the specific gravity (d) of the liquid is

For heavy media that has a specific gravity of liquid greater than that of water

d = 144.3 / (144.3-Be). … … … … … … … … … … … … … … … … … ①

In the case of an alarm field where the specific gravity of the liquid is lower than the specific gravity of the water

d = 144.3 / (134.3 + Be)... … … … … … … … … … … … … … … … … … ②

The present invention is to provide a method for producing a high-purity clean salt activated while having a low concentration of boron and bromine while solving the above problems.

In order to achieve the above object, the present invention is to take a deep sea water of 200m or less in depth to warm the temperature to 20 ~ 30 ℃, pretreatment filtration step of suspended solids in water by sand filtration, microfiltration, ultrafiltration, etc. adjusting the pH to 4.5-6.5, nanofiltration followed by reverse osmosis to produce brine, neutralizing the brine, neutralizing brine to produce concentrated brine in the electrodialysis process, concentration It is characterized by producing a high purity clean salt by a process consisting of evaporation and magnetization of the brine to precipitate the activated salt, dehydration and drying the precipitated salt, packaging and inspection step.

First of all, the characteristics of deep ocean water are 200 meters below sea level, and since the deep sea water does not reach the plankton because it does not reach the sun, unlike the sea water at the surface, high nutrients do not exist in the surface water. It is characterized by cleanliness, low temperature stability and mineral balance characteristics.

1. High nutrition

In the deep sea where sunlight does not reach, the photosynthesis by plankton is hardly performed, unlike seawater in the surface layer, so there is no consumption of inorganic nutrients (nitrogen, nitrate, phosphate, silicon) consumed by photosynthesis in the surface seawater. Due to the lack of activity, large amounts of nutrients are decomposed and eluted from organic matter, such as dead bodies of organisms that have settled from the surface, and high concentrations of nutrients exist because there is no plankton to use. .

2. Cleanliness

In the deep sea where sunlight does not reach, there is little plankton, so there are few organisms such as fish, there are few pathogenic microorganisms, and the possibility of contamination by pollutants from land and the atmosphere is very small compared to surface water, and it is very clean. .

3. Low Temperature Stability

Deep sea water is characterized by extremely stable water temperature changes at low temperature and high pressure without mixing with surface water from the difference in temperature and salinity.

4. Mineral Properties

Deep sea water contains a variety of essential trace elements similar to the minerals in human blood.

Since the salt dissolved in the deep sea water has the above characteristics, it is possible to produce high-quality clean salt because it contains various minerals that are hygienic and safe and useful to the human body compared to the natural salt produced from surface sea water.

As shown in Table 1, since heavy metals such as lead (Pb), cadmium (Cd), copper (Cu), and arsenic (As) and fluorine (F) are present in trace amounts, they are not a problem for human health. However, bromine (Br), known as a carcinogenic substance, and boron (B), which causes gastrointestinal and skin disorders, should be removed as much as possible.

Thus, the present invention proposes a method for producing clean salt of high purity, which is activated to have a good absorption efficiency to the human body, while removing bromine (Br) and boron (B) as much as possible to produce hygienically safe salt.

Deep sea water contains 4 to 5 mg / l of boron and is present in the form of boric acid (H ₃ BO ₃ ). Boric acid is B (OH) ₃ in acidic state with an ion radius of 0.23Å. Is less concentrated by nanofiltration and reverse osmosis.

Boric acid is present in the acidic state as B (OH) ₃ , but when the pH is neutral to alkaline, the boric acid is converted to gel boric acid as shown in the following reaction ③. do.

B (OH) ₃ + OH ^_ → Poly Boric acid ([B (OH) ₄ ] ^- , [B ₃ O ₃ (OH) ₄ ] ^- , [B ₄ O ₅ (OH) ₄ ] ^2- , [B ₅ O ₆ (OH) ₄ ] ^- ). … … … … … … … … … … … … … … … … … … … … … … … … … … … … … ③

Therefore, the present invention removes suspended solids (SS; Suspended solid) in the water by sand filtration, microfiltration, ultrafiltration, etc. Boric acid is treated in the state of B (OH) ₃ having a small particle size, followed by nanofiltration and reverse osmosis to obtain brine from which boric acid has been removed.

As shown in Tables 2 and 3, bromine (Br) exists mainly in the form of MgBr ₂ in seawater, and its solubility in water is higher than that of NaCl, while NaCl has a slight difference in solubility at high temperatures (40 to 100 ° C). However, there is a characteristic that the solubility increases at high temperature.

Therefore, in the present invention, salts having a low content of cancel (Br) in the precipitated salts are precipitated at a temperature in the range of 70-90 ° C. in the range of 30-32 ° Be. To be produced.

Table 2 Solubility in water according to the temperature of major salts in seawater (unit: g / 100ℓ water)

Kind of salt   0 ℃   10 ℃   20 ℃   30 ℃   40 ℃   50 ℃   60 ℃   70 ℃   80 ℃   90 ℃   100 ℃ CaSO ₄  0.1759  0.1928    -  0.2090  0.2097    -  0.2047  0.1966    -    -  0.1619 MgBr ₂ 6H ₂ O  91.0  94.5  96.5  99.2  101.6  104.1  107.5    -  113.7    -  120.2 MgSO ₄ 6H ₂ O  40.8  42.2  44.5  45.3    -  50.4  53.5  59.5  64.2  69.0  74.0  KCℓ  27.6  31.0  34.0  37.0  40.0  42.6  45.5  48.3  51.1  54.0  56.7  NaCℓ  35.7  35.8  36.0  36.3  36.6  37.0  37.3  37.8  38.4  39.0  39.8

Figure 5 shows the relationship between the concentration changes of various salts due to the concentration of deep sea water and the relationship between the precipitation amounts of salts in the deep sea water concentration process and the evaporative concentration of sea water in Table 3. In the "precipitates", CaSO ₄ begins to precipitate at 11.5 ° Be by evaporating seawater with a specific gravity of 3 ~ 4 ° Be and NaCℓ begins to precipitate from 25 ~ 26 ° Be. MgSO ₄ , MgCl ₂ precipitates when the temperature is above 32 ° Be. MgBr ₂ begins to precipitate.

                Table 3 Precipitation (g / l) in Seawater Evaporative Concentration

Specific gravity (° Be) Volume (cc) Fe ₂ O ₃ CaCO ₃ CaSO ₄ MgSO ₄ MgCℓ ₂ NaCℓ MgBr ₂ KCℓ 3.4 1,000 7.1 533 0.0030 0.0642 11.5 316 Trace 14.0 245 Trace 16.75 190 0.0530 0.5600 20.60 145.5 0.5020 22.00 131.0 0.1600 25.00 112.0 0.1508 26.25 95.0 0.1476 0.0040 0.0078 3.2614 27.0 64.0 0.1440 0.0130 0.0356 9.6500 28.50 39.0 0.0700 0.0260 0.0437 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 0.1535 27.1074 0.2224 Remaining water   - 1.8548 3.1640 0.5885 0.3300 0.5335 Sum   - 0.0030 0.1172 1.7488 2.4788 3.3175 27.6959 0.5524 0.5335

In the electrodialysis process, concentrated brine concentrated in the range of 18 ~ 20 ° Be is evaporated and NaCl starts to precipitate from 25 ~ 26 ° Be, and when MgSO ₄ , MgCl ₂ The back is precipitated, and then Since MgBr ₂ also precipitates, salts with a low concentration of bromine (Br) are precipitated below 32 ° Be.

Hereinafter, the present invention will be described in detail with reference to the drawings.

In FIG. 1, the deep sea water is taken from the deep seabed of 200 m or less, and the intake method is to take the pipe down to 200 m or less from the ship's bottom, or install the pipe to the sea level 200 m or less, and then take it with a pump. Or, pipes are installed up to 200m below sea level, and the intake wells are installed below sea level to take water according to siphon principle.

The deep ocean water collected in the sump is warmed to 20 ~ 30 ℃ because of its low viscosity and high filtration efficiency.

The warming method may be supplied with heat from a boiler, or may use sea surface water in summer.

The warmed deep sea water is filtered through sand filtration, micro filtration, ultra filtration alone or a combination of two or more of them. And pretreatment filtration to remove suspended solids (SS) which may cause fouling in Reverse Osmosis filter.

Sand filtration does not need to be performed if the turbidity of the ocean waters withdrawn is less than 2 mg / l.

At this time, the filtration pressure is determined in consideration of the pressure loss of the filter and the pressure loss of the pipe according to the operating conditions.The filtration speed of sand filtration is 6-10 m / hour, and the effective diameter of the filter sand is 0.3-0.45 mm, the uniformity coefficient shall be 2.0 or less, and the thickness of the filtrate layer shall be 0.5-1.0 m.

Microfiltration and ultrafiltration are independent of the type of filtration membrane, and the supply pressure of the pump is determined in consideration of the filtration speed and the pressure loss according to the specifications of the vendor.

Deep seawater from which suspended solids have been removed from the pre-filtration process is sent to a pH adjustment process to adjust the pH to a weak acidity in the range of 4.5 to 6.5 so that the scale is suppressed as much as possible in the nanofiltration membrane or the reverse osmosis membrane. Hydrochloric acid (HCl) is used as inorganic modifier.

In the pH adjustment method, the pH is adjusted to 4.5 to 6.5 while injecting a pH adjuster into the pre-filtered deep sea water while stirring the stirring time (retention time) for 15 to 30 minutes with a propeller agitator of 180 to 360 RPM (rotation speed). After adjustment, it is sent to the nanofiltration process.

The membrane modules of nanofiltration and reverse osmosis are tubular, hollow fiber, spiral wound, and plate and frame. It may be used in any form such as), and the material of the film is not particularly limited.

After removing the suspended solids in the pretreatment filtration process, the deep seawater with the salt concentration of 3 ~ 3.5wt% is adjusted to the range of 4.5 ~ 6.5 in the pH adjustment process and supplied to the nano filter process. As the solubility of CaCO ₃ , CaSO ₄ , SrSO ₄ is small, the salt is concentrated in reverse osmosis and electrodialysis, and scale is formed in the membrane to prevent fouling. Supply pressure is 15-25 atmosphere (atm) to remove CaCO ₃ , CaSO ₄ , MgCl ₂ , MgSO ₄ , SrSO _{4, which} are divalent or more minerals, in the range of 80-90 wt% In the case of the spiral, the membrane permeate amount is 0.7 to 1.4 m 3 / m 2 · day, and the membrane permeate amount is 80 to 90% of the inflow.

When demineralized water from which CaCO ₃ , CaSO ₄ , MgCl ₂ , MgSO ₄ and SrSO ₄ has been removed from the nanofiltration is supplied to the reverse osmosis process, the operating pressure is supplied to the filtration membrane at 50 to 60 atm. In the case of the filtration membrane, when the membrane permeated water is operated at 0.5 to 0.8 ㎥ / ㎡ · day, the salt (NaCl) is removed in the range of 99.0 to 99.85wt%, and the demineralized salt desalted is sent to the drinking water manufacturing process. Is sent to the neutralization tank (11).

At this time, the recovery rate of the brine is 50 to 60%, the salt concentration is 5 to 6wt%.

The brine flowing into the neutralization tank (11) of the neutralization process is pH 6.5 while stirring with the neutralization tank stirrer (12) while supplying 5-10 wt% of an aqueous solution of NaOH, NaHCO ₃ , Na ₂ CO ₃ as a neutralizing agent. Neutralization is carried out in the range of ˜7.5 and sent to the desalination chamber 6 of the electrodialysis process by the brine transfer pump 13.

In the present invention, the electrodialysis apparatus of the electrodialysis process is to separate the potential difference of the direct current power supply from the rectifier 10 by the membrane permeation of the ionic solute with the driving force. The cation exchange membrane 3 selectively permeates cations having a fixed negative charge, and the anion exchange membrane 2 uses an ion exchange membrane that selectively permeates an anion having a fixed static charge. .

As shown in FIG. 2, the electrodialysis apparatus 1 suppresses scale troubles, increases the limit current density while improving salt concentration efficiency, and improves the treatment efficiency so as to improve the treatment efficiency. The anion exchange membrane 2 is alternately installed between the anode 8 and the cathode 9 in a row in a row, and the anode 8 and the cathode chamber of the anode chamber 4 at both ends are arranged. The neutralized brine was supplied to the desalination chamber 6 with the brine feed pump 13 while applying a direct current from the rectifier 10 to the cathode 9 of (5). Desalination in the range of / l while some are returned to the neutralization tank (11), the demineralized mineral water (demineralized water) is operated by the electric conductivity indicating switch (ECIS: Electric conductivity indicating switch (Solenoid valve; ⓢ) operation To the mineral manufacturing process, the concentrated brine of the concentrated brine storage tank (14) in the salt concentration chamber (7) When circulated and supplied by the concentrated brine transfer pump 15, the cations in the brine pass through the cation exchange membrane 3 by electric attraction, and move to the salt concentration chamber 7 on the negative electrode 9 side, and the anion is anion exchange membrane. (2) is concentrated and removed as the salt is concentrated and removed as it moves to the salt concentration chamber (7) on the anode side (8). It is sent to the upper part of the evaporation tower 25 of the evaporation and magnetization process by the operation of the solenoid valve ⓢ by a bame indicating switch (BIS).

In this case, the electrical conductivity is an index indicating the degree of conductivity of the aqueous solution, and the salt concentration in the water is measured. The unit is S / m (Siemens / m) corresponding to the inverse of the electrical resistivity of the aqueous solution. The relationship between (EC) and soluble salts (TSS) in water is as follows.

TSS (ppm) = 640 X EC (mS / cm). … … … … … … … … … … … … … … … … … … ④

 The electrodialysis apparatus 1 preferably increases the current density as much as possible within the range below the limit current density in order to increase the processing performance. However, the limit current density is proportional to the salt concentration, Since the thickness of the diffusion layer is inversely proportional to the thickness of (iii), it depends on the salt concentration in the mineral water, which is the demineralized water to be drained, and the salt concentration of the concentrated brine. Thus, in the present invention, the cation exchange membrane 3 and the anion exchange membrane ( The brine neutralized in the electrodialysis apparatus 1 forming the desalination chamber 6 and the salt concentration chamber 7 in which 2) is alternately arranged between the anode 8 and the cathode 9 is a salt transfer pump 13 The desalination chamber (5) is sent to the desalination chamber (5) after desalination, and part of the circulation is concentrated, and the concentrated brine is sent to the salt concentration chamber (7) by the concentrated brine transfer pump (15), thereby improving the desalination and salt concentration efficiency. 7) scale components are produced in the salt concentration chamber (7). By supplying a large amount of concentrated brine passing through the salt concentration chamber 7 so as not to form, scale trouble can be prevented reliably, and by supplying the concentrated salt solution with a high salt concentration to the salt concentration chamber 7, the liquid resistance of the current ( I) Since the limit current density can be increased because there is less, there is a feature that the processing performance of the electrodialysis apparatus 1 can be improved.

In order to improve the electrodialysis efficiency and to suppress scale trouble by increasing the amount of energization by increasing the limit current density in the electrodialysis apparatus 1, the flow rate supplied to the desalination chamber 6 is the membrane surface velocity. Demineralized water (mineral water) desalted in the range of 10 to 30 cm / sec is returned to the neutralization tank 11, and the flow rate of the concentrated brine supplied to the salt concentration chamber 7 is 1 to 3 The concentrated brine is returned to the concentrated brine reservoir 14 so that the cm / sec range is maintained.

In the deep sea water, such as CaSO ₄ , CaCO ₃ , solubility in water is low, and when concentrated, a scale is generated, so that the treatment efficiency may be reduced due to fouling of the membrane. Multivalent ionic substances (CaSO ₄ , CaCO ₃ , MgCl ₂ , MgSO ₄ , SrSO ₄ ..., Etc.) were first removed, and CaSO ₄ , CaCO ₃ , SrSO ₄ . In order to suppress the generation of scale as much as possible, an ion-exchange membrane is used in which the divalent or higher ionic material is poorly permeable and selectively transmits only the monovalent ionic material.

The cation exchange membrane (3) used in the present invention is an exchange membrane that selectively permeates only monovalent cations while suppressing the permeation of divalent or higher polyvalent cations, and is a polystyrene-divinylbenzene-based main chain. The side chain of polyethyleneimine or polyvinylpyridine is attached to the negatively charged membrane that fixes negative charge -SO ₃ ^- in the main chain. Graft polymer such as) or an ion exchange membrane synthesized with a graft polymer whose main chain is polystyrene is a side chain of polyethyleneimine or polyvinyl pyridine, and the main chain of the graft polymer is the same molecule as the main chain or side chain of the cation exchange membrane. Any structure can be used without limitation, and preferably, polyethylene, polypropylene, polyvinyl chloride, Polyvinyl pyridine molecular structure having a cation exchange membrane in the main chain or a side chain only one cation permeability (透過能) with the same molecular structure and a polymer consisting of fixing the ^(- Li styrene (polystyrene) or the like negatively charged R-SO ₃ Cation exchange membranes such as Polyvinylpyridine, Polyvinylamine or Polyethyleneimine membranes may be used, and in particular, polystyrene-graft-ethylene imine based on polystyrene-divinylbenzene may be most preferably used.

The anion exchange membrane (2) is a membrane capable of exchanging anions on the contrary to the cation exchange membrane (3), which fixes the static charge R-NH ₃ ⁺ to the polymer chain and prevents the static charge. It is also called a static charge membrane because it is fixed to the membrane, and an ion exchange group is crosslinked by aliphatic hydrocarbons, and a thin layer of a polymer material having a cation exchange group on the surface of the membrane. (Iii) It is preferable to cross-link and quaternize the monomer introduced into the exchanger with aliphatic hydrocarbon at the same time. The polymer material having a cation exchange group includes a polymer electrolyte having a cation exchange group and a cation exchange group. Insoluble polymers having a linear polymer electrolyte or a cation exchange group, specifically, sulfonic acid such as Ligninsulfonate. ((Sulfonate), phosphate ester salts such as higher alcohol phosphate esters, such as polymer electrolytes having a cation exchange group with a molecular weight of 500 or more, methacrylic acid, carboxylic acid groups such as styrene sulfonic acid (-COOH) Cations such as condensation of linear polymer electrolytes containing a large number of monomer units having a sulfonic acid group (-SO ₃ H), phenols and aldehydes including cation exchange groups. A membrane for selectively exchanging monovalent anions such as an insoluble polymer having an exchange group is used.

The anode 8 of the anode chamber 5 of the electrodialysis apparatus 1 is made of a corrosion-resistant material and a DSA (Dimensionally Stable Anode) electrode or a platinum plated electrode having high hydrogen and oxygen generation overvoltage. The solution passed through the cathode chamber 5 is injected to suppress the generation of chlorine and oxygen on the surface of the anode 8, and the cathode 9 has a high nickel generation overvoltage (Ranney nickel). ) Or a cation exchange membrane 3 closest to the cathode chamber 5 by using a stainless steel sheet and using a hydrogen ion impermeable membrane or a monoanionic ion permeable membrane. It is preferable to reduce the amount of hydrogen ions generated on the surface to improve power efficiency and reduce odor.

In addition, in the salt concentration chamber 7, a polarity switching device is installed in the rectifier 10 in preparation for the generation of scale or slimes such as organic matters to reduce the processing efficiency. ) And the negative electrode 9 are switched to detach the attached scale and slime.

The electrolyte solution of the electrode chamber is supplied to the cathode chamber 5 to supply the electrolyte solution discharged from the cathode chamber 5 to the cathode chamber 4, and the electrolyte solution (cathode chamber solution) supplied to the cathode chamber 5 is Seawater (deep sea water) may be used, but 3-10 wt% Na ₂ SO ₄ Using an aqueous solution can suppress corrosion of the electrode and generation of chlorine (Cl ₂ ) gas at the anode 8.

Concentrated brine concentrated in the range of 18-20 ° Be in the electrodialysis process is compressed to the magnetization process by sending the water of the salt-precipitation tank 16 to the magnetizer 20 by the conveying pump 19. The air supplied from the blower 24 is supplied downward through the heat exchanger 26 heated by the burner 25 while the air is sent together to the upper part of the evaporation tower 21 and sprayed through the spray nozzle 26. Then, the evaporated water is discharged to the atmosphere through the demister 23 while the countercurrent contact with the hot air air is carried out, and the evaporated water is concentrated in the center well of the salt extraction tank 16. When the precipitated salt is sent to the well), when the salt is precipitated, it is collected by the salt precipitation tank rake 17 to the lower center cone. Center wells by dehydration feed pump (29) b) when the bomedo specific gravity is within the range of 30 ~ 32 ° Be while returning to the elbow, it is discharged into the product of the water by the operation of the solenoid valve (ⓢ) by the bomedo specific gravity control controller (BIS), and the deposited salt It is processed, dehydrated and sent to a drying process to make clean salt. The dried clean salt is packaged and then commercialized.

The evaporation tower 21 is preferably made of flame-resistant titanium or SUS-316L. However, in consideration of economical efficiency, FRP (Fiber reinforced plastics) resin or epoxy resin is applied to the steel sheet. Lining or coating.

In order to improve the spraying efficiency of the injection nozzle 22, compressed air is supplied at a pressure of 1 to 6 atm on the upstream side, and a mass ratio of air and liquid is supplied at a ratio of 1.1 to 1.2. .

The heating of the hot air air supplied from the blower 24 uses heavy oil or light oil in the burner 25, but may use natural gas (LNG) or liquid petroleum gas (LPG), and the temperature of the hot air is 150 to The temperature of the wet air discharged to the atmosphere through the demister 23 is set to 400 ° C, and the evaporation tower 25 is only subjected to the constant drying. The temperature of the evaporated brine discharged to the salt-precipitation tank 16 is designed so that the height of the tower is 80 ° C. or less so that thermally weak components are not thermally decomposed.

 The water flow in the salt-precipitation tank 16 flows into the return water storage tank 18, and the flow rate of the return water of the return pump 19 is 2 to 4 times the flow rate of the neutralized treated brine and the concentrated mineral water. .

The flow rate of the hot air air supplied from the blower 28 required for drying evaporation is determined by reducing the heat loss by 5-10% to the value obtained from the enthalpy and the material balance of the device entrance.

When the flow rate of the hot air air supplied from the blower 28 is determined, the top diameter of the evaporation tower 25 shall have the flow rate of hot air air of 3 to 5 m / sec.

The angle α of the lower cone of the evaporation tower 21 is designed to be 10 ° ≦ α ≦ 60 °, and the ratio of the diameter D of the discharge portion to the diameter D of the evaporation tower 21 is compared. ) Is designed in the range of 0.3≤D。 / D≤0.7.

The salt-precipitation tank (16), return water storage tank (18) and dehydration liquid storage tank (28) are made of epoxy coated on reinforced concrete, or lined with FRP resin or epoxy resin on titanium, SUS-316L, or steel sheet. Or coated.

The diameter of the salt-precipitation tank 16 has a solid load of 60-90 kg / m 2 · day of precipitation salt, a depth of 3-4 m, and a slope of the bottom of the bottom in the range of 1.5 / 10 to 2.5 / 10. To be designed).

The salt-precipitation tank rake 17 also uses the above-described flame-retardant material or coated with an epoxy resin on a steel sheet, and the rotation speed is 0.02 to 0.05 rpm, and the power of the speed reducer is equal to the diameter of the salt-precipitation tank 16. The torque is determined by taking into account the state of the precipitated salt.

The conveying pump (19), screw conveyor (27), dehydration liquid feed pump (29), and dehydrator are made of titanium or SUS-316L. All brine pipes are made of titanium, SUS-316L, PE (polyethylene), and PVC. (Poly vinyl chlorde) Resin tube is used.

The magnetizer 20 installed on the discharge side of the conveying pump may be installed with a permanent magnet magnetized in the range of 12,000 to 15,000 G (Gauss), synthetic resin (PVC, PE, styrene resin, etc.), ebonite, FRP. Is applied to a coil wound around a cylindrical conductive tube of insulating material such as Bakelite, when a low voltage of AC or DC is applied in the range of 0.5 to 5 V, a constant voltage conductor is formed so that a magnetic field is formed inside the coil. Use firearms.

Concentrated brine concentrated in the electrodialysis process is sent to the upper part of the evaporation tower 21 of the evaporation and magnetization process, and the concentrated mineral water is returned after the hydrolysis process of the salt precipitation tank 16 is magnetized and compressed air (spray particles Supplying hot air to the lower part of the evaporation tower 21 while supplying hot air to the lower part of the evaporation tower 21 together, the water is evaporated while making countercurrent contact with each other, and is discharged to the atmosphere through the upper demister 23, When the evaporated water is sent to the salt-precipitation tank 16, as shown in FIGS. 4, 5, and 4, the water is evaporated, and NaCl is precipitated when the specific gravity is 25 to 26 ° Be.

When the evaporation is continued and the temperature of the salt-precipitation tank 16 reaches a specific gravity of 30 to 32 ° Be at 80 ° C, MgCℓ ₂ and MgSO ₄ are precipitated, and then MgBr ₂ also begins to precipitate.

Therefore, in the present invention, the dehydration liquid at a specific gravity of 30-32 ° Be is discharged to the liver water product so that a low bromine concentration (salt) is produced.

In the above-described concentration of deep sea water by ion exchange membrane electrodialysis, cations such as Na ⁺ , K ⁺ , Ca ^{2 +} , Mg ^{2 + in the} deep sea water pass through the cation exchange membrane, and Cl ⁻ , Br ⁻ , SO ₄ ^{2 -} is an anion such as a salt is concentrated by passing through an anion exchange membrane that, at this time, the two monovalent cations than ion (Na ^+, K ⁺⁾ and negative ions (Cl ^-) It is easy to pass through, which is Ca ²⁺ Hydrated water with low concentrations of ions such as, Mg ^{2 +} , and SO ₄ ^{2 -} is produced. In particular, sulfate ions (SO ₄ ^2- ) with large ions are difficult to pass through. concentration is remaining Ca ^{2 +} low as chloride ^ion is particularly change each salt concentration, as in the combination with calcium chloride (CaCl ₂₎ of Figure 7 is the "concentration of salts contained in the electrodialysis step also" (Cl) There is a characteristic that the water containing calcium chloride is produced in the water.

The magnetization of the transfer function by installing the magnetizer 20 in the discharge pipe of the conveying pump 19 causes the salt to be activated, and the activated salt can be improved in absorption efficiency when ingested.

As described above, in the present invention, since the deep sea water has an infinite amount of pure water and contains various minerals useful for the human body, the present invention compares to the natural salt produced in marine surface water. It is expected to have a widespread effect on salt production since it can produce high quality salts while being hygienically safe.

Claims (1)

1. After warming the deep seawater collected at a depth of 200m or below at 20 ~ 30 ℃, perform pretreatment filtration of sand filtration, microfiltration and ultrafiltration alone or in combination of two or more. 2. The pre-filtered filtrate is adjusted to 4.5 ~ 6.5 and sent to the first reverse osmosis filtration process. The demineralized water is sent to the beverage manufacturing process and the concentrated brine is sent to the nanofiltration process. 3. The concentrated brine from the first reverse osmosis filtration process is sent to the nanofiltration and supplied to the filtration membrane at 15-25 atm. The divalent or higher minerals CaCO ₃ , CaSO ₄ , MgCl ₂ , MgSO ₄ , and SrSO ₄ are The brine from which CaCO ₃ , CaSO ₄ , MgCl ₂ , MgSO ₄ , and SrSO ₄ , which is a divalent or higher mineral component, is sent to the mineral manufacturing process, is sent to the neutralization tank 11. 4. A 5-10 wt% aqueous solution of one of NaOH, NaHCO ₃ and Na ₂ CO ₃ was supplied to the brine from which the mineral component sent to the neutralization tank 11 was removed as a neutralizer, and stirred with a neutralization agitator 12. The pH is neutralized in the range of 6.5 to 7.5. 5. The desalination treatment was carried out in the range of 400-800 mg / l by supplying the neutralized brine to the desalination chamber 6 while applying a direct current from the rectifier 10 to the desalination chamber 6 with a brine transfer pump 13. While some are returned to the neutralization tank (11), the demineralized mineral water is sent to the mineral manufacturing process by the operation of a solenoid valve (ⓢ) by an electric conductivity indicating switch (ECIS), salt The concentrated brine of the concentrated brine storage tank 14 is supplied to the concentrated chamber 7 by the concentrated brine transfer pump 15 and circulated, so that the cations in the brine penetrate the cation exchange membrane 3 by electrical attraction to the cathode 9. It moves to the salt concentration chamber 7 of the side, and anion passes through the anion-exchange membrane 2, and moves to the salt concentration chamber 7 of the anode 8 side, and the bomedo gravity of the concentrated brine storage tank 14 is 18-. Concentrated brine concentrated in the range of 20 ° Be It is sent to the upper part of the evaporation tower 21 of the evaporation and magnetization process by the operation of the solenoid valve ⓢ by a dicating switch (BIS). 6. When the concentrated brine concentrated in the range of 18 to 20 ° Be is sent to the upper part of the evaporation tower 21 of the evaporation and magnetization process, the water of the salt precipitation tank 16 is returned to the conveying pump 19. The air supplied from the blower 24 is heated to the burner 25 by sending the magnetized water and compressed air together to the upper portion of the evaporation tower 21 by spraying through the spray nozzle 22. When the hot air heated by the heat exchanger 30 is supplied to the lower portion of the evaporation tower 21, the evaporated water is released to the atmosphere through the demister 27 while countercurrently contacting the hot air air. , The evaporated concentrated function is sent to the center well of the salt-precipitation tank 30, and when the precipitated salts are precipitated, they are collected by the salt-precipitation tank rake 31 to the lower center cone. Send to dehydration process. 7. The precipitated salt is sent to the dehydration process and the dehydrated filtrate is sent to the dehydration filtrate storage tank (35) and returned to the center well of the salt precipitation tank (30) by the dehydration filtrate transfer pump (36). When it is discharged to the water products by the operation of the solenoid (ⓢ) valve by the BOME, the precipitated salt is dehydrated, dehydrated and sent to a drying process to produce clean salt. Method for producing a high purity clean salt from deep sea water by the above-described process.

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