JP2001157555A - Bittern-containing common salt grain and method for producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a common salt having mild deliciousness of natural salt and also decreased in deliquescence and caking property, to provide a method for producing the salt, and to provide a method for effectively utilizing seawater in association with the above method for producing the salt. SOLUTION: The bittern-containing common salt grains are such ones as to have cores of bittern-containing compositions which may contain NaCl; wherein the core surface is coated with a coating layer made of an NaCl-containing composition which may contain CaSO4 or bittern. A method for fractionating seawater into freshwater, an NaCl-containing composition and a bittern-containing composition and collecting the resultant water and compositions comprises either a process of fractionating seawater into freshwater and salt-containing water by reverse osmosis membrane treatment followed by fractionating the salt-containing water into NaCl-containing composition and bittern-containing composition by ion-exchange treatment, or process of fractionating seawater into NaCl-containing aqueous solution and bittern-containing aqueous solution by ion-exchange treatment followed by fractionating the NaCl- containing aqueous solution and bittern-containing aqueous solution into freshwater, NaCl-containing composition, and bittern-containing composition each by reverse osmosis membrane treatment.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a salt obtained by reducing the deliquescence and coagulability of a natural salt while having a mild taste. More specifically, the present invention relates to a salt obtained by improving the taste by containing a mineral component in seawater, and eliminating disadvantages such as deliquescence and coagulation. The present invention also relates to a method and an apparatus for producing the salt.

[0002] The present invention further relates to a method for effectively utilizing seawater in the production of the above-mentioned salt. Specifically, the present invention relates to a method for efficiently separating and recovering fresh water and the above-mentioned salt raw material from seawater and producing the above-mentioned salt from the salt raw material.

[0003]

2. Description of the Related Art Unrefined salt produced from seawater has a delicious salty taste that cannot be realized by purified salt because it contains a mineral component (nigari) such as magnesium chloride contained in seawater. However, since bittern has the deliquescent property of absorbing and dissolving moisture in the atmosphere, the unpurified salt has a property (coagulability) that absorbs and gradually solidifies based on the deliquescent of the bittern. However, there is a drawback that storage stability is poor and handling is difficult.

[0004] In order to solve this drawback, conventionally, as a table salt, a purified salt highly purified to contain a high concentration of NaCl (99.4% or more) by removing bittern components by an ion exchange membrane method. Is used. For this reason, although table salt has no deliquescent and is easy to handle, it has a drawback that the original taste of bittern-derived salt cannot be obtained.

[0005] For this reason, various processed salts have been conventionally proposed in order to solve problems such as the hygroscopicity of the salt.
For example, Japanese Patent Publication No. 55-16625 discloses a processed salt in which hygroscopicity is suppressed by fixing a sodium or potassium salt of an organic acid on a salt crystal surface, and Japanese Patent Publication No. 54-25105 discloses a salt crystal. A processed salt is disclosed that enhances the taste of salt and reduces hygroscopicity by coating a small amount of licorice extract on the surface. Japanese Patent Application Laid-Open No. 1-181762 discloses a processing salt in which a seasoning component, a flavoring component, and the like are used as a nucleus, and the surface of the nucleus is coated with a crystal salt to encapsulate the inside flavoring component and the like with good airtightness. It has been disclosed. The processed salt described in Japanese Patent Application Laid-Open No. 1-181762 is a salt obtained by adding umami to a salty taste with a seasoning component used for a core.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to solve the conventional problems relating to salt and to provide a salt which is delicious and excellent in handleability, and a method for producing the same. Specifically, first, the present invention has a unique umami or salty taste to a natural salt by containing a mineral component of seawater, and also has an improved storability and handleability by reducing deliquescence and coagulation. It is an object of the present invention to provide salt. Secondly, it is another object of the present invention to provide a method for producing the above salt and an apparatus suitable for the production method.

Thirdly, in producing the above-mentioned salt using seawater, the present invention efficiently separates and recovers a raw material of the salt from seawater without wasting the seawater, and further produces fresh water produced as a by-product. The purpose is to make effective use of That is, from another viewpoint, the present invention also provides a method for effectively utilizing seawater.

[0008]

Means for Solving the Problems The inventors of the present invention have studied diligently with the aim of improving the taste and suppressing the deliquescence of salt, and found that a bittern-containing composition containing a large amount of bittern is used as a core. By coating the surface of the nucleus with a composition of sodium chloride or sodium sulfate or a sodium chloride composition containing bittern in a smaller proportion than the above-mentioned core component, deliquescence is significantly suppressed, and a salt having a delicious taste peculiar to natural salt is obtained. It has been found that it can be prepared.

The present invention has been developed based on such knowledge.

That is, the present invention provides the following (1) to (4)
(1) A bittern-containing composition that may contain sodium chloride is used as a core, and the surface of the core is coated with a coating layer made of a sodium chloride-containing composition that may contain calcium sulfate. A bittern-containing salt grain, comprising: (2) The coating layer is composed of a composition containing bittern and sodium chloride, and the percentage of bittern contained in the coating layer is smaller than the percentage of bittern contained in the core bittern-containing composition (1). ) The bittern-containing salt particles described in the above. (3) The bittern-containing composition according to any of (1) or (2), wherein the blending ratio of bittern contained in the core bittern-containing composition is 15 to 90% by weight per 100% by weight of the core. Salt grains. (4) The mixing ratio of bittern contained in the coating layer is such that the coating layer 1
10% by weight or less, preferably 5% by weight per 00% by weight
The bittern-containing salt particles according to (2) or (3), wherein:

The present invention also provides a method for preparing the above-mentioned salt described in the following (5) to (8): (5) A method for preparing a salt containing a bittern-containing composition which may contain sodium chloride, comprising the steps of: The bittern-containing composition according to (1), wherein the surface of the core particles is coated with a sodium chloride-containing composition optionally containing calcium sulfate by spraying and drying an aqueous solution containing sodium chloride which may contain calcium sulfate. Manufacturing method of salt granules. (6) Spraying and drying an aqueous solution of sodium chloride containing bittern at a smaller ratio than the bittern content contained in the core particles, on the surface of the core particles made of the bittern-containing composition which may contain sodium chloride. The method for producing bittern-containing salt particles according to (3) or (4), wherein the surface of the core particles is coated with a composition containing bittern and sodium chloride. (7) The core particles composed of the bittern-containing composition that may contain sodium chloride and the coating particles composed of the sodium chloride-containing composition that may contain calcium sulfate are supplied to a spray-drying apparatus, and these particles are treated. The method for producing bittern-containing salt particles according to (1), wherein the coating particles are adhered to the surface of the core particles by spraying a binder to form a coating layer. (8) Spraying core particles composed of a bittern-containing composition that may contain sodium chloride, and coating particles composed of a composition containing bittern and sodium chloride in a ratio smaller than the bittern content contained in the core particles. The bittern-containing salt particles according to any one of the above (2) to (4), wherein the particles are supplied to a drying apparatus, and a binder is sprayed on the particles to cause the coating particles to adhere to the surface of the core particles to form a coating layer. Manufacturing method.

Further, the present invention is an apparatus for preparing the above-mentioned salt described in the following (9) to (11): (9) a casing having an air supply port, an exhaust port and an outlet for the generated bittern-containing salt particles. A supply device for supplying core particles made of a bittern-containing composition that may contain sodium chloride in the casing, and spraying the supplied core particles with an aqueous solution of sodium chloride that may contain calcium sulfate or bittern. A spray nozzle, a spray liquid supply unit for supplying the sodium chloride aqueous solution to the nozzle, an air supply device for supplying air for drying, and a discharger for discharging the generated bittern-containing salt particles. Dry equipment. (10) A casing provided with an air supply port, an exhaust port, and an outlet for the generated bittern-containing salt particles, core particles made of a bittern-containing composition that may contain sodium chloride in the casing, and calcium sulfate or bittern. A feeder for supplying coating particles composed of a sodium chloride-containing composition which may be contained, a nozzle for spraying a binder to the supplied core particles and coating particles,
A spray drying apparatus, comprising: a spray liquid supply unit for supplying a binder to the nozzle; an air supply device for supplying air for drying; and a discharger for discharging the generated bittern-containing salt particles. (11) a casing having an air supply port, an exhaust port, and an outlet for the generated bittern-containing salt particles, a nozzle for spraying an aqueous solution of a bittern-containing composition which may contain sodium chloride in the casing, A spray liquid supply unit for supplying an aqueous solution of the bittern-containing composition, a nozzle for spraying a sodium chloride-containing aqueous solution that may contain calcium sulfate or bittern in a casing, and a spray for supplying the sodium chloride-containing aqueous solution to the nozzle Liquid supply section,
A spray drying apparatus comprising: an air supply device for supplying air for drying; and a discharger for discharging the generated bittern-containing salt particles.

Further, the present invention relates to a method for efficiently separating and recovering fresh water, a composition containing sodium chloride and a composition containing bittern from seawater, as described in the following (12) to (13). (12) a step of subjecting seawater to reverse osmosis filtration membrane treatment to separate fresh water and salt-containing water, and then separating the resulting salt-containing water into a sodium chloride-containing composition and a bittern-containing composition by ion exchange treatment. Or, seawater is separated into an aqueous solution containing sodium chloride and an aqueous solution containing bittern by ion exchange treatment, and then the obtained aqueous solution containing sodium chloride and the aqueous solution containing bittern are subjected to reverse osmosis filtration membrane treatment, respectively, to obtain fresh water and a composition containing sodium chloride. A method for separating and recovering freshwater, a sodium chloride-containing composition, and a bittern-containing composition from seawater, comprising a step of separating the salt from the bittern-containing composition. (13) a step of treating seawater with a reverse osmosis filtration membrane to separate it into freshwater and salt-containing water, and separating the salt-containing water obtained in the above step into a sodium chloride-containing composition and a bittern-containing composition by ion exchange treatment Step, further comprising a step of subjecting the sodium chloride-containing composition or bittern-containing composition obtained in the step to a reverse osmosis filtration membrane to separate the mixture into freshwater and a sodium chloride-containing composition or bittern-containing composition, from seawater to freshwater. , A method for separating and collecting a sodium chloride-containing composition and a bittern-containing composition.

The above separation and recovery method is a method for producing and obtaining fresh water, a composition containing sodium chloride and a composition containing bittern from seawater as a raw material from another viewpoint. Accordingly, the present invention includes fresh water, a composition containing sodium chloride and a composition containing bittern obtained by the method.

[0015] The present invention further relates to a salt obtained from the above sodium chloride-containing composition and bittern-containing composition obtained from seawater, and to a method for producing the same. (14) The sodium chloride-containing composition and the bittern-containing composition obtained by the method of the above (12) or (13) include the sodium chloride-containing composition and the sodium chloride, each of which may contain calcium sulfate or bittern. Prepared as a bittern-containing composition that may be
The bittern-containing salt particles according to any one of (1) to (4). (15) The sodium chloride-containing composition and the bittern-containing composition obtained by the method of the above (12) or (13) include the sodium chloride-containing composition and the sodium chloride, each of which may contain calcium sulfate or bittern. The method for producing bittern-containing salt particles according to any one of (5) to (8), wherein the bittern-containing salt particles are produced by using a spray-drying method as the bittern-containing composition that may be used.

[0016]

DETAILED DESCRIPTION OF THE INVENTION (1) Bittern-containing salt particles The bittern-containing salt particles of the present invention, as shown in FIG. 1 or 2, have a multilayer structure composed of a core 1 and a coating layer 2 covering the surface thereof. It is characterized by. Specifically, the bittern-containing salt particles of the present invention have a bittern-containing composition, which may contain sodium chloride (NaCl), as core particles, and the surface of the core particles is sodium chloride (NaCl) or at least calcium sulfate ( CaSO ₄ ) and sodium chloride (NaC
The bittern-containing salt particles are characterized by being coated with a coating layer comprising a composition containing 1). The bittern containing sodium chloride grains be in the form of nuclear particles 1 surface covered coated with a coating layer 2 as shown in FIG. 1, also coating layer core particles 1 the surface of the particulate, as shown in FIG. 2 (coated particles )
It may be in a form covered with 2 , or in any form.

In the present invention, bittern means a mineral component contained in seawater. Specific examples include those obtained by concentrating the residual liquid containing various minerals after removing NaCl from seawater, and those obtained by concentrating and purifying as necessary. The bittern contains at least magnesium chloride, magnesium sulfate, potassium chloride and calcium sulfate.

The bittern-containing composition constituting the core of bittern-containing salt grains of the present invention may be a composition comprising the above bittern, or a composition containing NaCl in addition to the bittern. The mixing ratio of each component contained in bittern is not particularly limited, but it is preferable that the components are mixed at approximately the mixing ratio based on the ratio of bittern components (seawater minerals) contained in seawater. In seawater,
It is generally known that, in addition to sodium chloride, magnesium chloride, magnesium sulfate, calcium sulfate, and potassium chloride are contained at the ratios (weight ratios) shown in Table 1.

[0019]

[Table 1]

Thus, although not limited, magnesium chloride, magnesium sulfate,
When the total amount is 100 parts by weight, the proportions of calcium sulfate and potassium chloride are 35 to 55 parts by weight, 15 to 35 parts by weight, 10 to 30 parts by weight, and 0.1, respectively.
-20 parts by weight can be exemplified.

The bittern-containing composition is 100% of the bittern described above.
Or a composition containing other components in addition to bittern. In this case, although not limited, the bittern is 15 to 95% by weight, preferably 15 to 90% by weight, more preferably 3 to 100% by weight of the core composition.
It is preferable to contain it in a ratio of 0 to 90% by weight.

Preferably, the other component is NaCl. In this case, the blending ratio of NaCl contained in 100% by weight of the core composition is not particularly limited as long as the bittern content in the core composition falls within the above range, and is usually 5 to 85% by weight. , Preferably 10 to 85% by weight, more preferably 10 to 70% by weight.

In addition, in addition to the bittern component derived from seawater or NaCl, the bittern-containing composition may further artificially contain calcium sulfate or the like as a filler.

The coating layer formed around the surface of the nucleus (core particles) is preferably made of a component having a low hygroscopic property so that the deliquescent of bittern contained in the nucleus can be significantly suppressed, and made of NaCl Even if CaSO ₄ and N
It may be composed of a composition containing aCl. The mixing ratio of CaSO ₄ contained in the latter composition is not particularly limited, but is preferably 10% by weight or less, preferably 5% by weight or less per 100% by weight of the coating layer. The lower limit of the content of CaSO ₄ is not particularly limited as long as it is more than 0, but it is preferable to add 0.01% by weight or more.

The above-mentioned CaSO _{4 is used} as a component of the coating layer.
Can be used instead of. In this case, the bittern is used in a smaller ratio than the mixing ratio of bittern contained in the core particles (the bittern-containing composition) described above. Preferably, it is 10% by weight or less, more preferably 5% by weight or less, per 100% by weight of the coating layer. The blending lower limit is not particularly limited as long as it is more than 0, but it is preferable that the blending amount is 0.01% by weight or more. By coating the core particles with a coating layer containing NaCl and bittern at the above ratio, it is possible to prepare salt (grain) having a good taste while preventing deliquescence caused by bittern. In addition, calcium sulfate, magnesium carbonate, calcium carbonate, magnesium oxide, and the like can be artificially added to the coating layer component as a filler.

As described above, a preferred embodiment of the bittern-containing salt particles of the present invention has a bittern-containing composition which may contain NaCl as a nucleus, and the surface of which is contained in the bittern-containing composition constituting the above-mentioned core. It is coated with a coating layer made of a NaCl-containing composition containing bittern less than bittern. Particularly preferred salt grains of the present invention have a two- or more-layered structure composed of the core (core particles) and a coating layer described above, but the composition as a whole has a component composition of seawater. .

Thus, the salt grains of the present invention have a mineral balance close to that of seawater and can have a mellow umami salty taste without salt. Further, the salt grains of the present invention have excellent preservability and handleability as a result of significantly reducing deliquescence caused by bittern and coagulation based on the deliquescence based on the multilayer structure.

(2) Method and apparatus for producing bittern-containing salt particles The bittern-containing salt particles of the present invention can be produced by a spray drying method. Therefore, the present invention provides a method for producing the above-mentioned bittern-containing salt particles by a spray drying method. In the method, a bittern-containing composition serving as a nucleus is prepared in advance as a particulate solid, and a component serving as a coating layer is sprayed and dried in a solution state on the surface of the nuclei particles by a spray-drying method. Both the bittern-containing composition and the components to be the coating layer are prepared in advance as particulate solids (core particles and coating particles), and the coating particles are attached to the surface of the core particles by a spray-drying method using a binder. A method of forming a coating layer by spraying, by applying both a core component and a coating component in a solution state to a spray drying device, spraying the coating component in a solution state onto the surface of the core particles formed inside the spray drying device, Any of the methods of forming

Hereinafter, these manufacturing methods and the apparatuses used for carrying out the methods will be specifically described with reference to the drawings. However, these figures are examples for embodying the method and apparatus for producing bittern-containing salt grains of the present invention, which is a technical idea, and the present invention is not limited to these specific methods and apparatuses. is not.

FIG. 3 shows N 2 previously prepared as a granular solid.
Bittern-containing composition (core particle) optionally containing aCl
A NaCl-containing composition containing NaCl or CaSO ₄ or bittern on the surface of the core particles by spraying and drying an aqueous solution of NaCl or a NaCl-containing aqueous solution containing CaSO ₄ or bittern on the surface of BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic explanatory view showing one embodiment of a spray-drying apparatus 3 for preparing salt particles having a coating layer formed of a product (hereinafter, also referred to as a coating composition).

In this case, the core composed of the bittern-containing composition can be prepared using seawater as a raw material. Specifically, for example, NaCl is selectively removed from seawater using an ion exchange membrane, the obtained de-NaCl water is concentrated using a reverse osmosis filtration membrane, and water is further evaporated by a vacuum evaporation method or the like. Or the seawater is concentrated using a reverse osmosis filtration membrane, and then the NaCl component is selectively removed with an ion exchange membrane,
The bittern-containing composition can be prepared as a solid, preferably as a particulate solid, by further evaporating water from the obtained de-NaCl concentrated water by a vacuum evaporation method or the like. When the core contains NaCl together with bittern, the seawater is directly concentrated by a reverse osmosis membrane method or the like, and the bittern-containing composition is solidified by evaporating water by a vacuum evaporation method or the like. It can be prepared as a solid. In this case, when water is evaporated by a vacuum evaporation method or the like, the generated particles are washed with water or an aqueous solution of NaCl, whereby the content of bittern contained in the core particles can be reduced and adjusted.

Although not limited, an aqueous solution of NaCl or an aqueous solution of NaCl containing CaSO ₄ or bittern can also be prepared using seawater as a raw material. For example, a NaCl aqueous solution can be prepared by a method of selectively recovering an aqueous solution containing a NaCl component from seawater using an ion exchange membrane. In this case, the seawater may be concentrated by the reverse osmosis membrane method or the evaporation method and then subjected to the ion exchange treatment, or the NaCl aqueous solution obtained by the ion exchange treatment may be further concentrated by the reverse osmosis membrane method or the evaporation method as necessary. You can also. CaSO ₄
Alternatively, the NaCl-containing aqueous solution containing bittern is
It may be prepared by adding and mixing CaSO ₄ or bittern into a Cl aqueous solution, or it may be prepared directly from seawater. As a method of preparing from seawater, for example, CaSO
_The NaCl aqueous solution containing ₄ can be prepared by a method of selectively recovering an aqueous solution containing a CaSO ₄ component and a NaCl component from seawater using an ion exchange membrane. A bittern-containing NaCl aqueous solution can also be prepared by directly concentrating seawater by a reverse osmosis membrane method or the like, but seawater is separated into a NaCl-containing fraction and a bittern-containing fraction by ion exchange treatment, and each fraction is required. After concentrating by a reverse osmosis membrane method or an evaporation method according to the above, both are mixed at an appropriate ratio, preferably at a ratio that is lower than the ratio of bittern contained in the bittern-containing composition constituting the nucleus. Can also be prepared.

The spray drying apparatus 3 shown in FIG. 3, a casing 4 having an air supply port a, the outlet c of the exhaust port b and generated bittern containing sodium chloride grains, Na into the casing 4
A supply device 5 for supplying core particles made of a bittern-containing composition that may contain Cl;
₄ or nozzles 6 for spraying a good NaCl containing aqueous solution also contain bittern, and the NaCl to the nozzle 6
A spray liquid supply unit 7 for supplying a contained aqueous solution, an air supply device 8 for supplying air for drying, and a discharger 9 for discharging generated bittern-containing salt particles are provided.

The casing 4 has a slender cylindrical shape, and a cyclone 10 is connected to the upper exhaust port b . The cyclone 10 is desirably configured to provide a filter or the like so as to separate and remove particles contained in the air exhausted from the casing 4 and discharge only the air. . This can prevent the bittern-containing salt particles from being discharged together with the air.

The casing 4 has a perforated plate 11 below the inside of the cylinder. The perforated plate 11 is made of a plate material or a net material provided with a large number of holes, has a conical shape that is inclined downward toward the center of the cylindrical hollow of the casing,
The center of the cone is connected to a discharger 9 via a discharge port c .

The air supply device 8 is arranged so as to supply dry air from below the perforated plate 11 through the air supply port a of the casing 4 . As a result, the dry air passes through the holes of the perforated plate 11 from the bottom upward, and the casing 4
Is blown up toward the exhaust port b provided at the upper part of the air conditioner.
The air supplied by the air supply device 8 is not particularly limited as long as it is dry air, and may be either heated dry air or non-heated dry air. Heat drying air is preferred because it can be dried more quickly. The air supply device 8
It is preferable that air be blown into the casing 4 in a direction substantially perpendicular to the axis of the casing. The air injected in this direction rises while rotating inside the casing along the inner wall surface thereof, and discharges the bittern-containing salt particles generated inside the casing through the cylindrical hollow center portion of the casing into the discharge port c and the discharger communicating therewith. Drop it toward 9 .

The nozzle 6 is provided inside the casing 4 with the perforated plate 1.
1 is arranged to come below the upwardly and feed opening of the feeder 5 supplies nuclear particles than. The nozzle 6 communicates with the spray liquid supply unit 7 , and NaCl is supplied from the supply unit.
Aqueous solution or NaCl containing CaSO ₄ or bittern
Containing aqueous solution (coating solution) is supplied, In addition, the spray liquid supply unit 7 includes reservoir 7b of the coating solution is pressurized feeder 7a and spray liquid, such as a pump, for pressurizing feeder 7a The spray liquid is sprayed by the nozzle 6
Can be sprayed upward into the casing 4 .
The coating aqueous solution is preferably sprayed radially as fine mist particles by the nozzle 6. Specifically, the size of such particles is, for example, 1 to 10
0 μm, preferably 5 to 50 μm, more preferably 1 μm
0 to 30 μm can be exemplified.

The discharger 9 arranged in communication with the discharge port c of the casing 4 has a bottom surface that is narrowed down in a tapered (conical) shape, and the perforated plate 1 is formed at the conical apex of the bottom surface.
The bittern-containing salt particles that have fallen from the center of 1 through the discharge port c accumulate. The conical apex on the bottom is a rotary feeder
It is open so that it can be discharged to the outside through 12 .

That is, according to the spray drying apparatus 3 shown in FIG. 3, the core particles composed of the bittern-containing composition supplied from the supply device 5 and the fine particles of the coating aqueous solution sprayed from the nozzle 6 are formed into a perforated plate. The aqueous coating solution particles stirred by the dry air blown up from below through 11 adhere to the surface of the core particles and are dried. By repeating this, the bittern-containing salt particles having a larger particle size due to the coating composition (coating layer) adhering to the surface fall through the cylindrical hollow center of the casing 4 to the bottom of the casing. The bittern-containing salt particles pass through a discharge port c at the center of the perforated plate 11 and are discharged by
9 , and is discharged from the discharger 9 to the outside through the rotary feeder 12 .

The spray drying apparatus described above forms a coating layer on the surface of the core particles by applying the coating composition in a solution state to the core particles in a solid state and then drying the coating composition. Can be also produced by attaching a solid-state coating composition to solid-state core particles via a binder.

FIG. 4 shows a spray drying apparatus for realizing this.
Shown in As shown in FIG. 4, the spray drying apparatus 3
Is a bittern-containing composition that may contain NaCl and NaCl or NaCl containing CaSO ₄ or bittern.
Both of the contained compositions are supplied to the casing 4 in the form of solid particles, and the nozzle 6 is configured to spray the binder in a solution state. Core particles comprising a bittern-containing composition which may contain NaCl and NaCl or CaSO
₄ or a coating particles consisting of NaCl-containing composition comprising a bittern, a separate feeder 5 as shown in FIG. 4
From it may be supplied to the casing 4, or both may be supplied from the supply unit 5 in premixed state to the casing 4.

The solution used as the binder is not particularly limited, and examples thereof include water and an aqueous solution of NaCl. According to a binder such as water or an aqueous NaCl solution, the surface of the solid core particles can be dissolved, and the solid coating particles can be adhered to the dissolved surface. It is also possible to use, as a binder, an adhesive component for bonding the core particles and the coating particles without dissolving the surfaces thereof.

According to the spray drying apparatus shown in FIGS. 3 and 4, it is possible to continuously produce bittern-containing salt particles.

The bittern-containing salt particles of the present invention can also be produced using a spray drying apparatus as shown in FIG. The spray drying apparatus 3 has a cylindrical casing 4 having an air supply port a at the bottom and an exhaust port b at the top, and a bag filter 13 at an upper inside.
The bittern-containing salt particles prepared by drying with dry air supplied from the bottom of the casing by the air supply device 8 are collected by the bag filter 13 . According to the device, a core composed of the bittern-containing composition which is previously disposed at the bottom of the casing 4 (in this case, the feeder 5 shown in FIG. 5 is unnecessary) or which is supplied from the feeder 5 to the bottom of the casing 4 By spraying and drying an aqueous coating solution from the nozzle 6 on the particles 1 , the surface of the core particles is made of NaCl or CaSO ₄ or Na containing Nigari.
It can also be coated with a Cl-containing composition. In addition, the bitter-containing composition which may contain NaCl serving as a nucleus and the NaCl-containing composition which contains NaCl or CaSO ₄ or bittern as a coating layer are supplied in a solid state (particles) in a feeder 5.
The coating layer can be formed on the surface of the core particles by supplying the binder to the casing 4 and spraying the binder from the nozzle 6 .

According to this apparatus, the generated bittern-containing salt particles are trapped and collected by the bag filter 13 , so that the bittern-containing salt particles are not discharged to the outside together with air, and a high recovery rate is obtained. Thus, bittern-containing salt grains can be obtained.

The apparatus shown in FIGS. 3 to 5 described above is one in which the bittern-containing composition serving as a core is supplied into the casing in a solid state.

The bittern-containing salt granules of the present invention contain N
The bittern-containing composition, which may contain aCl, may be supplied to a spray-drying apparatus in a solution state similarly to the coating composition without previously preparing the composition in a solid state, and may be prepared by a spray-drying method.

FIG. 6 shows a spray drying apparatus for realizing this.
Shown in

A blade-drying apparatus 3 shown in FIG. 6 is different from the spray-drying apparatus shown in FIG. 3 in that a bitter-containing composition which may contain NaCl for forming core particles instead of the feeder 5 shown in FIG. A nozzle 14 for spraying an aqueous solution of the product downward, and a spray liquid supply unit 15 for supplying the aqueous solution of the bittern-containing composition to the nozzle. The spray liquid supply unit 15 basically includes a pressurized feeder 15a such as a pump and a storage tank 15b for the spray liquid (aqueous solution of the bittern-containing composition), and can supply the nozzle 14 with the aqueous solution of the bittern-containing composition. It has become. Nozzle 1
Like the supply device 5 shown in FIG. 3, the reference numeral 4 is disposed above the inside of the casing 4 so as to be located above the nozzle 6 for spraying the coating solution upward.

The aqueous solution of the bittern-containing composition that may contain NaCl used here can be prepared as it is from seawater or from seawater as a raw material.
In the latter case, the aqueous solution of the bittern-containing composition is, for example, a method of concentrating seawater by a reverse osmosis membrane method or an evaporation method, selectively removing NaCl from seawater using an ion exchange membrane, and further optionally The obtained de-NaCl water is concentrated by a reverse osmosis membrane method or an evaporation method, or the seawater is concentrated by a reverse osmosis membrane method or an evaporation method.
It can be prepared by a method of removing Cl or the like.

According to the spray drying apparatus 3 , the aqueous solution of the bittern-containing composition sprayed downward from the nozzle 14 is dried while falling in the casing 4 to become solid core particles. . Fine particles of the coating aqueous solution sprayed upward from a nozzle 6 disposed in a lower part of the inside of the casing 4 adhere to the surface of the core particles, and are supplied from below the casing 4. The bittern-containing salt particles of the present invention can be dried while being stirred with dry air. The generated bittern-containing salt particles pass through the discharge port c at the center of the perforated plate 11 of the casing 4 and pass through the discharge device 9.
And is discharged to the outside through the rotary feeder 12 .

In the spray drying apparatus, both a bittern-containing composition which may contain NaCl as a central nucleus and a coating composition for forming a coating layer are supplied from a nozzle into a casing, respectively, in a solution state. Therefore, labor and time for preparing these compositions in a solid state in advance can be omitted, and the bittern-containing salt particles of the present invention can be efficiently and continuously produced.

(3) Method for separating and recovering freshwater, NaCl-containing composition and bittern-containing composition from seawater The present invention relates to a method for separating and collecting freshwater, NaCl-containing composition and bittern-containing composition from seawater.

The separation and recovery method according to the present invention can be carried out by subjecting seawater to filtration (membrane) treatment such as reverse osmosis filtration membrane treatment and ion exchange treatment. Specifically, in one embodiment, the method of the present invention comprises treating seawater with a reverse osmosis filtration membrane to separate it into fresh water and salt-containing water, and then subjecting the resulting salt-containing water to a NaCl-containing composition by ion exchange treatment. And a bittern-containing composition. In addition, the NaCl-containing composition or bittern-containing composition obtained in the above step may be further subjected to reverse osmosis filtration membrane treatment to collect and remove fresh water to obtain a concentrate. In still another embodiment, the method of the present invention comprises separating seawater into an NaCl-containing aqueous solution and a bittern-containing aqueous solution by ion exchange treatment, and then subjecting the obtained NaCl-containing aqueous solution and bittern-containing aqueous solution to reverse osmosis filtration membrane treatment, respectively. Fresh water and NaC
It can be carried out by fractionation into a l-containing composition and a bittern-containing composition.

The seawater used as a raw material is not particularly limited, and may be any of surface water, middle water, deep water and ultra-deep water. Seawater is passed through a filter or a filtration membrane before being subjected to the reverse osmosis filtration membrane treatment or the ion exchange treatment,
It is preferable to remove sand and foreign matter.

Here, the ion exchange treatment can be carried out using a conventional ion exchange resin or an ion exchange membrane having the property of selectively separating the NaCl component contained in seawater. The type of ion exchange membrane is not limited at all. In addition, since the ion exchange treatment can be performed in a large amount in a short time, it is preferable to perform the ion exchange treatment using an electrodialysis apparatus provided with an ion exchange membrane having the above properties.

The reverse osmosis filtration membrane used in the present invention only needs to have a property capable of separating and filtering fresh water and salt-containing water including NaCl and bittern. Regardless of the type, a film made of any material can be used. For example, as a material, cellulose, cellulose di-acetate or tri-acetate, polyamide, polysulfone, polystyrene,
Examples include polyimide and polyacrylonitrile.

FIG. 7 is a schematic diagram of a system (separation and recovery apparatus) for implementing the separation and recovery method of the present invention. The separation / collection device 16 includes at least a seawater tank 17 for taking and storing seawater, a filter 18 , a reverse osmosis filtration membrane processing unit.
19, ion exchange processing unit 20 , fresh water recovery unit 21 , NaC
l-containing composition recovery section 22 and bittern-containing composition recovery section 2
3 which are connected to each other by a line 24 .

As shown in the figure, the reverse osmosis filtration membrane processing section 19 in the separation / recovery apparatus 16 may be provided at two places after the treatment with the filter 18 and after the ion exchange treatment. It may be arranged only in.

In the separation / recovery device 16 , the seawater in the seawater tank 17 is supplied into the filter 18 by driving a circulation pump (not shown) to remove sand and other solid foreign matters contained in the seawater. You. Next, the obtained filtrate is supplied to the reverse osmosis filtration membrane treatment section 19 or the ion exchange treatment section 20 . When supplied to the reverse osmosis filtration membrane processing unit 19 ,
Seawater is separated into freshwater and salt-containing water, the freshwater is collected in a freshwater recovery unit 21 through a pipe 24 , and the salt-containing water is supplied to the ion exchange processing unit 20 .

[0061] Seawater is fed to the ion exchange treatment unit 20 or the concentrated salt-containing water is separated into NaCl-containing solution by ion exchange treatment and (composition) bittern containing aqueous solution (composition) and, respectively, conduit 24 Through N
The aCl-containing composition collecting section 22 and the bittern-containing composition collecting section 23 collect the liquid. In addition, these collection parts 22 or 2
The NaCl-containing composition or bittern-containing composition recovered in Step 3 can be further supplied to a reverse osmosis filtration membrane treatment section 19 ′ if necessary, whereby N 2 is gradually concentrated.
An aCl-containing composition or a bittern-containing composition can be obtained. The fresh water generated at this time is further collected by the fresh water collecting section 21 through the pipe 24 .

Thus, freshwater separated from seawater can be recovered and stored in the freshwater recovery section 21 , and the NaCl-containing composition containing a large amount of NaCl or NaCl contained in seawater can be recovered in the NaCl-containing composition recovery section 22 . Can be collected and stored, and the bittern-containing composition collecting section 23 can collect and store the bittern-containing composition containing a large amount of bittern components contained in seawater. The fresh water can be used as industrial water, daily life water or washing water, and can be used as drinking water by subjecting it to a sterilization treatment or the like. The NaCl-containing composition is used as a raw material for salt, pharmaceuticals and industrial NaCl.
Bittern-containing compositions are food additives, functional foods, pharmaceuticals,
It can be used as a raw material for bittern applicable to cosmetics.

Further, the NaC obtained by the above-mentioned fractional recovery method
The l-containing composition and the bittern-containing composition can be effectively used as a raw material of the bittern-containing salt particles of the present invention described above. That is, the bittern-containing salt granules of the present invention contain the NaC
l-containing composition as a coating composition (coating layer)
It can also be prepared by using a bittern-containing composition as a core composition (core particle component). Specifically, for example, the NaCl-containing composition obtained by the above method is
In a solution state, it can be used as a coating aqueous solution, or as a coating particle by further evaporating water by a vacuum evaporation method or the like to a solid state to produce the bittern-containing salt particles of the present invention. ,
In the state of a solution, it can be used as an aqueous solution for forming core particles, or as a core particle by evaporating water by a vacuum evaporation method or the like into a solid state to produce the bittern-containing salt particles of the present invention.

[0064]

The bittern-containing salt grains of the present invention have a unique taste and salty taste to natural salt by containing bittern, but deliquesce by reducing the bittern content on the surface that comes into contact with the atmosphere. It has the characteristic that the storability and the setting properties are significantly suppressed, and as a result, the storability and the handleability are excellent. In particular, the bittern-containing salt particles of the present invention obtained by the spray-drying method have a spherical or substantially spherical shape, so that the contact area between the particles is small, and in this respect, they are hard to coagulate and have a characteristic that they are smooth. In addition, the bittern-containing salt particles of the present invention, which can mix mineral components in seawater in a well-balanced manner, have a salty taste without a salty mellow taste and are good for the body.

Further, according to the method for producing bittern-containing salt particles of the present invention, salt having the above characteristics can be produced efficiently. In particular, according to the method according to claim 5 or 6, the coating composition can be attached to the core particles without using a binder, so that the bittern-containing salt containing no extra components other than bittern and NaCl. Granules can be manufactured efficiently. This means that according to the method of the present invention, by using seawater as a raw material, salt in which the mineral balance of seawater is maintained can be produced.

The present invention further provides a method for separating and recovering fresh water, bittern-containing components and NaCl-containing components from seawater, and using the obtained bittern-containing components and NaCl-containing components to produce the above bittern-containing salt grains. . According to this method, it is possible to produce a delicious and healthy salt utilizing all mineral components in seawater. In addition, according to the method, since seawater components can be used without leaving drainage, there is no environmental pollution and there is no risk of damaging the marine ecosystem. That is, the present invention can be positioned as a method for effectively utilizing seawater.

[0067]

EXAMPLES Examples will be described below in order to more specifically explain the present invention. However, the present invention is not limited by the embodiments.

Example 1 (1) Using 20 L of seawater, a NaCl-containing composition and a bittern-containing composition are obtained according to the system shown in FIG. Specifically, 20 L of seawater is passed through a membrane run filter to remove sand and other solids, and the obtained filtrate is filtered with a reverse osmosis membrane-type filtration device (SO-252-2NN, water treatment ace ( To separate into fresh water and concentrated salt-containing water. Fresh water is stored in the fresh water recovery section, while 12 L of salt-containing water
Electrodialysis device equipped with an ion-exchange membrane (cartridge) for selectively removing NaCl
(Type 3, Asahi Kasei) and fractionated into NaCl-containing fractions and other fractions (Nigari-containing fractions).

Using the NaCl-containing fraction obtained above as an aqueous coating solution and the bittern-containing fraction as an aqueous solution of a bittern-containing composition for forming core particles, using a spray drying apparatus shown in FIG. Make bittern-containing salt grains. Specifically, the NaCl-containing fraction is put into the storage tank 7b of the spray liquid supply unit, and the bittern-containing fraction is put into the storage tank 15b of the spray liquid supply unit, and the spray drying device is operated. Thereby, the aqueous solution of the bittern-containing composition sprayed radially downward from the nozzle 14 is dried while falling in the casing 4 to become solid core particles,
Fine particles of the coating aqueous solution sprayed upward from the nozzle 6 adhere to this, and are dried while being stirred by dry air supplied from below the casing 4. 600 g of the generated bittern-containing salt particles pass through the discharge port at the center of the perforated plate 11 of the casing 4 and fall and accumulate on the discharger 9.

(2) With regard to the salt granules thus obtained,
Each mixing ratio of sodium chloride, magnesium chloride, magnesium sulfate, calcium sulfate and potassium chloride,
The taste and deliquescence were examined.

Ingredient Analysis The analysis of each of the above compounding ratios was carried out according to the salt test method of the Salt Business Center of Japan (April 1, 1997).
Table 2 shows the results.

[0072]

[Table 2]

The taste

Ten panelists were asked to compare the taste of the bittern-containing salt grains of the present invention with purified salt (containing 99.5% or more of NaCl). As a result, the evaluation that the bittern-containing salt granules of the present invention had a mellow and delicious salty taste without a salty grain was obtained with a significant difference.

The salt prepared by spray-drying deliquescent seawater as it is and the bittern-containing salt particles of the present invention are kept at a constant temperature and humidity (25 ° C., humidity 7 ° C.).
5%), and the appearance change was observed. As a result, although the surface of the seawater spray-dried product was dissolved in one week and the surface was sticky, the bittern-containing salt particles of the present invention did not change even after two months, and maintained a smooth and granular shape. .

[Brief description of the drawings]

FIG. 1 is a sectional view showing bittern-containing salt particles of an example of the present invention.

FIG. 2 is a cross-sectional view showing bittern-containing salt particles of an example of the present invention.

FIG. 3 is a schematic cross-sectional view showing an example of a spray drying apparatus for producing bittern-containing salt particles.

FIG. 4 is a schematic sectional view showing another example of a blade blade ry apparatus for producing bittern-containing salt particles.

FIG. 5 is a schematic sectional view showing another example of a spray drying apparatus for producing bittern-containing salt particles.

FIG. 6 is a schematic sectional view showing another example of a spray drying apparatus for producing bittern-containing salt particles.

FIG. 7 is a schematic diagram showing a system for separating and recovering freshwater, a sodium chloride-containing composition, and a bittern-containing composition from seawater.

[Explanation of symbols]

 1. Nucleus (nuclear particle) 2. Coating layer (coating particles) Spray drying equipment 4. 4. Casing a: air supply port b: exhaust port c: discharge port Feeder 6. Nozzle 7. 7. Spray liquid supply section 7a: pressurized feeder 7b: spray liquid storage tank Air supply device 9. Discharge machine 10. Cyclone 11. Perforated plate 12. Rotary feeder 13. Bag filter 14. Nozzle 15. Spray liquid supply unit 15a: Pressurized supply machine 15b: Spray liquid storage tank Separation and recovery device 17. Seawater tank 18. Filter 19.19 '. Reverse osmosis filtration membrane treatment unit 20. Ion exchange processing unit 21. Freshwater recovery unit 22. NaCl-containing composition recovery section 23. Bittern-containing composition recovery unit 24. Pipeline

Continuation of the front page (72) Inventor Tadami Watanabe 2-11, Saikai, Saika-cho, Tokushima City, Tokushima Prefecture Inside the Tokushima Prefectural Industrial Technology Center

Claims (15)

[Claims] (1) A core containing a bittern-containing composition which may contain sodium chloride, and the surface of the core is coated with a coating layer comprising the sodium chloride-containing composition which may contain calcium sulfate. Characteristic bittern-containing salt grains. 2. A coating layer comprising a composition containing bittern and sodium chloride, wherein the ratio of bittern contained in the coating layer is:
2. The bittern-containing salt particles according to claim 1, wherein the percentage of bittern contained in the bittern-containing composition of the nucleus is less than that of the bittern. 3. The bittern-containing salt particles according to claim 1, wherein the mixing ratio of bittern contained in the bittern-containing composition of the core is 15 to 90% by weight per 100% by weight of the core. 4. The bittern-containing salt particles according to claim 2, wherein the mixing ratio of bittern contained in the coating layer is 10% by weight or less per 100% by weight of the coating layer. 5. A method for spraying and drying an aqueous solution containing sodium chloride, which may contain calcium sulfate, on the surface of a core particle comprising a bittern-containing composition which may contain sodium chloride, thereby drying the surface of the core particles. The method for producing bittern-containing salt particles according to claim 1, comprising a step of coating with a sodium chloride-containing composition which may contain calcium sulfate. 6. A spray of an aqueous solution of sodium chloride containing bittern at a smaller ratio than the bittern content contained in the core particles, on the surface of the core particles comprising the bittern-containing composition which may contain sodium chloride. The method for producing bittern-containing salt particles according to any one of claims 2 to 4, comprising a step of coating the surface of the core particles with a composition containing bittern and sodium chloride by drying. 7. A spray drying apparatus comprising supplying core particles composed of a bittern-containing composition that may contain sodium chloride and coating particles composed of a sodium chloride-containing composition that may contain calcium sulfate to a spray drying apparatus. The method for producing bittern-containing salt particles according to claim 1, wherein the coating particles are adhered to the surface of the core particles by spraying a binder onto the particles to form a coating layer. 8. Core particles comprising a bittern-containing composition which may contain sodium chloride, and coated particles comprising a composition containing bittern and sodium chloride in a proportion smaller than the bittern content contained in the core particles. Is supplied to a spray-drying apparatus, and a binder is sprayed on these particles so that coating particles are adhered to the surface of the core particles to form a coating layer. Production method. 9. A spray-drying apparatus for producing the bittern-containing salt particles according to claim 1, wherein the casing has an air supply port, an exhaust port, and a discharge port for generated bittern-containing salt particles. A supply device for supplying core particles composed of a bittern-containing composition that may contain sodium chloride in the casing, and spraying an aqueous solution containing sodium chloride that may contain calcium sulfate or bittern on the supplied core particles. A spray, comprising: a nozzle, a spray liquid supply unit for supplying the aqueous solution containing sodium chloride to the nozzle, an air supply device for supplying air for drying, and a discharger for discharging the generated bittern-containing salt particles. Dry equipment. 10. A spray-drying apparatus for producing the bittern-containing salt particles according to claim 1, wherein the casing has an air supply port, an exhaust port, and a discharge port for the generated bittern-containing salt particles. A feeder for supplying core particles comprising a bittern-containing composition which may contain sodium chloride and coating particles comprising a sodium chloride-containing composition which may contain calcium sulfate or bittern in the casing; A nozzle for spraying a binder to the core particles and the coating particles, a spray liquid supply unit for supplying the binder to the nozzle, an air supply device for supplying air for drying, and a discharge device for discharging the generated bittern-containing salt particles. A spray drying device, comprising: 11. A spray-drying apparatus for producing the bittern-containing salt particles according to claim 1, wherein the casing has an air supply port, an exhaust port, and a discharge port for the generated bittern-containing salt particles. A nozzle for spraying an aqueous solution of the bittern-containing composition that may contain sodium chloride in the casing, a spray liquid supply unit for supplying the aqueous solution of the bittern-containing composition to the nozzle, and calcium sulfate or bittern in the casing. A nozzle for spraying a sodium chloride-containing aqueous solution which may be sprayed, a spray liquid supply unit for supplying the sodium chloride-containing aqueous solution to the nozzle, an air supply device for supplying air for drying, and discharging the generated bittern-containing salt particles A spray drying device comprising a discharger. 12. A step of treating seawater with a reverse osmosis filtration membrane to separate it into fresh water and salt-containing water, and then separating the resulting salt-containing water into a sodium chloride-containing composition and a bittern-containing composition by ion exchange treatment. Or seawater is separated into an aqueous solution containing sodium chloride and an aqueous solution containing bittern by ion exchange treatment, and then the obtained aqueous solution containing sodium chloride and the aqueous solution containing bittern are subjected to reverse osmosis filtration membrane treatment, respectively, to obtain fresh water and sodium chloride-containing composition. A method for separating and recovering freshwater, a sodium chloride-containing composition, and a bittern-containing composition from seawater, comprising a step of separating the salt-water component and a bittern-containing composition from the seawater. 13. A process in which seawater is subjected to a reverse osmosis filtration membrane to separate it into fresh water and salt-containing water, and the salt-containing water obtained in the above step is subjected to an ion exchange treatment into a sodium chloride-containing composition and a bittern-containing composition. Seawater comprising a step of separating, further comprising a step of subjecting the sodium chloride-containing composition or bittern-containing composition obtained in the above step to a reverse osmosis filtration membrane treatment to separate fresh water and a sodium chloride-containing composition or bittern-containing composition. From fresh water, sodium chloride-containing composition and bittern-containing composition from water. 14. A seawater-derived sodium chloride-containing composition and a bittern-containing composition obtained by the method according to claim 12 or 13, wherein the sodium chloride-containing composition and the sodium chloride-containing composition, which may contain calcium sulfate or bittern, respectively. The bittern-containing salt particles according to any one of claims 1 to 4, prepared using the bittern-containing composition that may be contained. 15. A sodium chloride-containing composition and a bittern-containing composition derived from seawater obtained by the method of claim 12 or 13, wherein the sodium chloride-containing composition and the sodium chloride which may contain calcium sulfate or bittern, respectively. The method for producing bittern-containing salt particles according to any one of claims 5 to 8, wherein the bittern-containing salt particles are produced by using a spray drying method as the bittern-containing composition that may be contained.