JP6533936B2 - High concentration, large volume processing freeze concentrator - Google Patents

Description

  The present invention relates to obtaining a concentrate or a solute concentration dilute solution from a solution.

In the concentration by freezing , the solution is uniformly concentrated (the change in the mixing ratio of the multicomponent solutes of the resulting concentrate (each solution mass / total amount of solutes) is small) . It is also a low temperature technology. For this reason, it is considered as the technology which can obtain the highest quality concentrate compared with other concentration operation. Furthermore, concentration by freezing is an energy saving technology (the latent heat of solidification is about 1/7 of the latent heat of evaporation). However, freeze concentration techniques make it difficult to separate ice and concentrate. For this reason, in order to obtain a concentrated liquid having a high concentration, the construction and operation of the apparatus are complicated, the mobility is lacking, and the cost of the apparatus is high and not widespread. (Non-patent documents 1 and 2)

1.1 Method by Ice Column Generator Non-Patent Document 3 conducts research on a continuous processing freeze concentration apparatus in which a scraping surface ice making machine and a vertical cylindrical filter are connected. However, in the case of application to deep ocean water (with a salinity of 3.6%), the device described on the left can be concentrated by adding NaCl to deep ocean water, and the salinity of the concentrate obtained by the above-mentioned NaCl added deep ocean water It is reported that the concentration was 7% limit.

1.2 Method by Cooling Rotating Cylinder In recent years, research has been conducted on a freeze-concentrator having the following characteristics (Non-Patent Documents 4 and 5). 1) There is a large amount of processing and the cost of equipment is low. 2) The start up to steady operation is fast. 3) Intermittent operation of several hours and several days is possible.

The freeze concentration apparatus of the above non-patent documents 4 and 5 basically comprises an ice generator and a separator as described below.
The stock solution (concentrated solution) from the stock solution tank is sent to the ice generator stock solution tank of the ice generator. The ice generator (cooling rotary cylinder ice generator) comprises an ice generator stock solution tank, a cooling rotary cylinder immersed in the ice generator stock solution tank, and a rotary cylinder mounted close to the cooling rotary cylinder outer surface An ice liquid mixture (mixture of ice and concentrate) is formed from the stock solution on the outer surface of the cooled rotating cylinder, and the formed ice liquid mixture is continuously scraped off by the rotating cylinder scraping blade. Discharge to the outside of the ice generator.

The ice-liquid mixture produced by the ice generator is fed to the following separator (horizontal differential speed scraping blade separator) by a hopper and a tubular screw conveyor.
This separator is a porous wall basket (horizontal porous wall basket) whose rotation axis is horizontal and rotates at high speed, a porous screen which is attached to the inside of the high speed rotational porous wall basket and left with the high speed rotating porous wall basket It has a differential speed scraping blade (which rotates differentially with the rotation of the left basket) which rotates in close proximity to the screen on the left.
The operation of this separator is as follows. An ice fluid mixture from the ice generator is introduced into the back end of the basket (by the hopper and the tubular screw conveyor). The input ice fluid mixture is subjected to centrifugal force and spreads on the screen surface inside the high speed rotating porous wall basket. The spread ice liquid mixture separates the liquid (concentrate) in the ice liquid mixture from the ice liquid mixture by high-speed rotational centrifugal force while moving in the discharge direction by the differential speed scraping blade rotating close to the screen (liquid Will pass through the holes in the screen and high speed rotating porous wall basket). Separated ice (droplet of ice liquid mixture) is discharged from the discharge end of the basket to the outside of the basket by the rotational centrifugal force of the basket.

  In the freeze concentration test of seawater by the above-mentioned apparatus, the concentrate concentrations of 8.9 to 11.9 wt% and 9.8 to 9.8 to 1 at a stock solution concentration (salt content) of 3.1 to 3.4 wt% and 3.6 to 5.4 wt%, respectively. 15.9 wt% is obtained, and the recovery rate of the solute (= concentrate solution mass / stock solution solution mass) is 86%.

2. Ca and essential mineral components and seawater Ca ion is a signal transmitter to cells for maintaining vital activity and is a basic nutrient . For this reason, Ca is involved in most functions of the human body (living body), and the deficiency of Ca is the cause of a large number of important diseases (surgery myocardial infarction, arteriosclerosis, diabetes, senile dementia and bone Osteoporosis etc.). In addition, Ca is an essential mineral ingredient that is considered to be the most insufficient for Japanese (Ministry of Health, Labor and Welfare 2015).
On the other hand, various essential mineral components exert an effect of mutually affecting each other in the living body (maintaining the concentration balance). Unbalanced intake of minerals disrupts the in vivo mineral balance and causes various health problems (Non-patent Documents 6 and 7). Furthermore, in recent years the importance of essential trace mineral components and the need for a balanced intake have been identified.

Seawater has the following characteristics and can be a source of excellent natural mineral fluid to the human body (and living body).
a) Seawater contains all the essential mineral components necessary for the human body (and the living body).
b) Seawater is close to the human body (and living body) mineral balance (the mutual ratio of essential mineral components).
c) Minerals in seawater are ionized minerals that are highly absorbable from the digestive tract.
d) seawater concentrate Ru mineral liquid der natural without additives.
However, since seawater contains SO ₄ ions, Ca ions are significantly reduced during concentration (precipitating Ca 2 SO ₄ ). In addition, the mutual ratio of minerals changes during concentration . For this reason, it is difficult to produce a mineral concentrate which is rich in Ca from seawater and excellent in mineral balance.

3. High concentration concentration of seawater and retention of Ca ion 3.1 Evaporative concentration Sea water consumes a large amount of energy in normal evaporation concentration (the latent heat of vaporization is about 7 times the latent heat of solidification), and Ca SO ₄ and The Ca ₃ O ₃ scale precipitates, and the Ca component significantly decreases. Furthermore, the above-mentioned deposited scale causes the problem of the increase of the consumed heat energy due to the heat transfer resistance (Non-Patent Document 2) and the difficulty of removal due to the strong scale.

3.2 Seawater Desalination Technology There are two types of seawater concentration: flash evaporation and RO membrane (Reverse Osmosis) as seawater desalination technology. However, in the case of desalination of seawater (a salt concentration of 3.5 wt%), the salinity concentration of the concentrate which is the residual solution of desalination is 7 wt% or less. In order to obtain a concentrate having the above-mentioned concentration or more, the problem of Ca SO ₄ precipitation will occur. The deposition of Ca 2 SO ₄ leads to problems of scale on the evaporation heating surface, rapid deterioration of the RO film, and problems of reduction of the Ca component in the concentrate.

3.3 Enrichment of seawater with NF membrane + RO membrane and retention of Ca ion The SO ₄ ion is removed from seawater using NF membrane (Nano Filtration) (prevention of Ca SO ₄ deposition), and the liquid from which the SO ₄ ion is removed There is a technology to concentrate it with RO membrane. However, there are problems such as concentration concentration and limit of SO ₄ ion removal, reduction of recovery rate and fluctuation of mutual ratio .

a) High concentration concentration Non-patent documents 9 and 10 are carrying out development research of use of NF membrane + RO membrane for the purpose of concentration of deep ocean water. SO ₄ ions are removed from deep ocean water by an NF membrane, and the left liquid is concentrated to a high concentration by an RO membrane (high pressure). As a result of the test, the concentration is limited to the concentration of 15.1% (salt concentration) of the concentrate, and the result of 5 months continuous stable operation with a concentration of 14% of the concentrate is reported. In this study, recovery rate can be increased by returning the NF membrane treatment waste solution to the stock solution. However, in this case, the concentration of SO ₄ ions in the concentrate after RO membrane treatment will increase.

b) Low Concentration Enrichment Patent Document 1 also describes the use of an NF membrane + an RO membrane for the purpose of producing a concentrate having a high Ca content from seawater (and deep ocean water). The SO ₄ ions are removed from seawater by the NF membrane, and the left solution is concentrated at a low concentration by the RO membrane. The concentration from the low concentration solution (RO membrane treatment solution) to the high concentration solution is performed by evaporation (in the example, a vacuum evaporation method).

4. High concentration concentration of seawater by freezing and retention of Ca ion When non-patent documents 11 and 12 are performed by lowering the cooling temperature in freezing of seawater, precipitation of Na ₂ SO ₄ · 10H ₂ O occurs (cooling temperature It is noted that the SO ₄ ion concentration in the concentrate drops sharply (with non-patent reference 11) (non-patent document 11: salt concentration 23.3 wt%, freezing point −20.5 ° C., non-patent document 12: freezing point) -Experiment at 40 ° C).
The above description is seawater Non-Patent Document 11 (salinity (total solid matter) concentration of 3.5 wt%, SO ₄ ion concentration 0.27 wt%, Ca ion concentration 0.042wt%, Mg ion concentration 0.12 wt%) cooling Precipitation of Na ₂ SO ₄ · 10H ₂ O occurs from a salt concentration of about 9.8 wt% ( SO ₄ ion concentration about 0.7 wt%, Ca ion concentration about 0.17 wt%, freezing point about -6 ° C) Furthermore, it is supposed that the concentration of SO ₄ ions falls rapidly with the decrease of the cooling temperature (freezing point) (the increase of the concentration of the concentrate). At the same time, it is noted that the concentration of Ca increases with the decrease of the concentration of SO ₄ (it is exactly proportional to the concentration of the concentrate).

No. 5062728

Food industry 42 (11), Koetsu, 43-49, 1999

Journal of the Japan Seawater Society Vol. 60, No. 5 p. 336, p. 340 2006

Toyama Prefectural Industrial Technology Center-Research report, no. 15 III-52 to 2001

Chemical Engineering Journal, Vol. 29, No. 5, pp. 707-710 2003

Chemical Engineering Journal, Vol. 33, no. 4, pp. 319-322 2007

Calcium, Basic, Clinical, Nutrition, National Milk Spreading Association, Life Science Publishing Co., Ltd., pp. 236-251 1999

Health and nutrition-basic knowledge that you want to know, National Institute of Health and Nutrition, 1st publication p. 72 1999

New common knowledge of water and minerals, the document office, pp. 79-80, pp. 90-92 2000

Toyama Prefectural Industrial Technology Center-Research report, No. 17 III-47 to 48 2003

Toyama Prefectural Industrial Technology Center-Research report, No. 18 III-47 to 48 2004

Tokyo Industrial Research Institute Report No. 53, No. 11, 368-369 1958

T. G. Thompson et al. , Am, Sci. , 254, 227 1956

1. Freeze-concentrating device using a cooling-rotating cylindrical ice generator and a differential-speed scraping blade separator A freezing-concentrating device using a cooling-rotating cylindrical ice generator and a differential speed scraping blade separator of the above description (0004 to 0007) Face the challenges of
1.1 Inclusion of ice in the concentrate The problem of incorporation of ice in the concentrate separated from the ice liquid mixture in the separator arises.

1.2 Use of Hopper and Screw Conveyor In this device, the supply of ice fluid mixture from the ice generator to the separator is performed by a hopper and a tubular screw conveyor (hereinafter sometimes referred to as a hopper-screw conveyor). The use of the hopper and screw conveyor causes the following problems.
a) Crosslinking of the ice liquid mixture is likely to occur at the connection between the hopper and screw conveyor.
b) The smaller the device and the smaller the separator, the smaller the pipe diameter of the screw conveyor. For this reason, the smaller the size of the device, the screw conveyor determines the throughput of the device, and the smaller the size of the device, the greater the reduction of the throughput of the device. Also, the opening width of the hopper outlet should be equal to or less than the diameter of the screw conveyor. For this reason, the smaller the size of the apparatus, the more the ice liquid mixture is clogged in the hopper, which makes it impossible to supply the ice liquid mixture.
c) This device produces less ice fluid mixture in the ice generator than the possible throughput of the ice fluid mixture in the separator. For this reason, the operation of increasing the amount of ice liquid mixture produced by the ice generator and the ice generator should be a plurality of devices for one separator, but due to the problems a) and b), the throughput of the device Can not increase.
d) The increase of connections and moving parts in the device (by using hopper and screw conveyor) will increase the probability of failure of the device.

2. Production of Concentrated Natural Mineral Concentrate from Seawater Production of concentrated concentrate of natural mineral from seawater is, according to the prior art, retention and concentration of Ca mineral ions in the concentrate and mineral balance, and also operation of the device, cost of the device, There are problems / limits in energy consumption .

The method and apparatus for freeze concentration according to the present invention basically comprises the following ice generating unit and separating unit in order to solve the above problems.
The ice generator uses the ice generator described above (0005). The outer surface of the cooling rotary cylinder is cooled by flowing brine or refrigerant (freon or the like) over the inner surface of the rotating cylinder using a refrigerator.
This ice generating part has the following characteristics in the present invention.
1. The unit volume of the apparatus and the throughput of the undiluted solution per unit time (the volume of the ice liquid mixture) can be extremely increased for the following reasons.
The unit solution volume and the cooling area per unit time (the area of the outer surface of the cooled rotating cylinder) are very large.
The temperature difference between the stock solution and the stock solution cooling surface (the outer surface of the cooling rotary cylinder) can be set extremely large.
2. An ice liquid mixture of concentrated liquid with high concentration ratio can be generated for the following reasons.
・ The temperature difference between the stock solution and the stock solution cooling surface can be set extremely large.
-The cooling rotary cylinder forms an ice-liquid mixture on the outer surface of the cooling rotary cylinder when the cooling rotary cylinder is immersed in the ice generator stock solution tank, and forms with the rotation of the cooling rotary cylinder (formed on the outer surface of the cooling rotary cylinder The ice liquid mixture leaves the liquid surface of the stock solution tank and cooling of the ice liquid mixture proceeds in gas (in air, etc.). For this reason, in the ice-liquid mixture leaving the liquid surface of the stock solution tank, the ratio of the liquid in the ice-liquid mixture decreases (the ratio of ice decreases) without the liquid (concentrate) in the ice-liquid mixture spreading in the stock solution tank. The concentration of the liquid (concentrate) increases.
3. A concentrate having a target concentration can be easily and rapidly obtained for the following reasons.
· Concentrated solution of desired concentration by simple operation (adjustment of the cooling temperature, rotation speed, and undiluted solution solute concentration of the cooling rotating cylinder to change the ratio of ice and concentrated solution of the generated ice liquid mixture), or solute concentration dilution A liquid (a liquid obtained by melting separated ice described below) can be easily and rapidly obtained.

  The ice-liquid mixture produced in the ice producing section is sent to the separating section. The following describes the case where the means for moving the ice-liquid mixture from the ice generation unit to the separation unit is a natural drop. Spontaneous drop enables mass movement of the ice-liquid mixture (multiplication of throughput), simplification of the apparatus, and the like. The simplification of the device (reducing the number of connection and operation parts of the device) will reduce the probability of failure of the device. Note that this natural fall may be performed between the combination of a plurality of ice generating units and one separating unit. Also, the means for moving the ice-liquid mixture by natural fall may be natural fall via a belt conveyor. For this reason, the separation unit may be located above the ice generation unit.

The separation unit here has a structure capable of receiving the ice-liquid mixture from the ice generation unit by natural fall and continuously processing it (vertical differential speed scraping blade separator). This separator is a high speed rotating porous wall basket, a porous screen mounted on the inside of the high speed rotating porous wall basket and rotated integrally with the high speed rotating porous wall basket, a differential speed scraper rotating close to the left screen. Of the separation housing at the upper end (upper part of the separated ice outlet) or lower end (lower part of the separated ice outlet) of the removal blade (rotating differentially with the rotation of the basket) and left high speed rotating porous wall basket An attached ice scraping blade is provided that rotates with the high speed rotating porous wall basket in close proximity to the inner wall.
The operation of this separator is as follows. An ice-liquid mixture from the ice generator is dropped to the bottom or top of the high-speed rotating porous wall basket by free fall. The input ice fluid mixture is subjected to rotational centrifugal force and spreads on the screen surface inside the high-speed rotating porous wall basket. The spread ice liquid mixture separates the liquid (concentrate) in the ice liquid mixture from the ice liquid mixture by high-speed rotational centrifugal force while moving in the discharge direction by the differential speed scraping blade rotating close to the screen (liquid Will pass through the holes in the screen and high speed rotating porous wall basket). Separated ice (droplet of ice liquid mixture) is discharged from the discharge end (upper end or lower end) of the high speed rotating porous wall basket to the outside of the basket by the rotating centrifugal force and the attached ice scraping blade of the high speed rotating porous wall basket .

The adhered ice scraping blade in the above is to scrape the separated ice which adheres to and accumulates on the inner wall of the separator housing at the separated ice outlet of the differential speed scraping blade separator. The (part of) separated ice discharged from the discharge end of the high-speed rotating porous wall basket adheres to the inner wall of the separator housing as it is attached, and the adhesion thickness is gradually increased (the high-speed rotating porous wall forming the passing liquid chamber) It passes through the clearance (which separates the basket and the stationary fixed wall of the separator) and mixes with the concentrate. In the present invention, in order to prevent mixing of the separated ice into the concentrate, the attached ice scraper rotates together with the high speed rotating porous wall basket close to the inner wall of the separator housing at the discharge end of the high speed rotating porous wall basket. Set up a removal blade. The attached ice scraping blade may be provided at either of the discharge ends of the vertical differential scraping blade separator and the horizontal differential scraping blade separator, which are the differential scraping blade separator of the present invention. It can.

  The shape of the high-speed rotating porous wall basket may be cylindrical or conical.

Further, in the present invention, the separation part (the ice liquid mixture is separated into the separation ice and the concentrated liquid) may be used as other means (for example, a batch type basket type solid-liquid centrifuge) other than the differential speed scraping blade separator.

  The operation of the separation unit separates the ice-liquid mixture into a liquid (concentrate) and separated ice. The separated ice separated may be melted. The melted separated ice becomes a solute concentration dilute liquid (having a lower solute concentration than the stock solution). The present invention may be directed to obtaining this separated ice or a solute concentration dilute solution.

  In the present invention, in order to further concentrate (or dilute the solute concentration) the concentrate (or solute concentration dilute liquid) obtained by the combination of the ice generating part and the separating part, the conditions of the ice generating part or the ice forming part and the separating part The method and apparatus may be performed twice or more by changing (for example, the cooling temperature of the cooling rotary cylinder).

  In addition, the method and apparatus of the present invention may utilize the concentrate and solute concentration dilute solution obtained in the middle of the process for other products or applications other than the first purpose.

  In the present invention, a plurality of ice generators in the ice generator may be used as a method and apparatus for one separator in the separator.

  Further, according to the present invention, the supply of the ice liquid mixture from the ice generation unit to the separation unit may be a method other than the spontaneous fall. For example, use of a hopper and a screw conveyor, or manual supply of an ice liquid mixture to the separation unit by manual operation or the like may be used.

Using the method of the present invention from the description of the 0015 stock was allowed to precipitate simultaneously Na _{2 SO} 4 _· 10H 2 O to generate the temperature of sea water and over 6 ° C. or less Korieki mixture cooled rotating cylindrical ice generator as seawater, Next, by using the separation part of the present invention, the separated ice and the Na ₂ SO ₄ · 10H ₂ O precipitate are separated and removed together from the above ice-liquid mixture , thereby reducing the concentration of SO ₄ ions (at the same time the Na ion is reduced). A concentrate can be obtained. In addition, in order to further concentrate the concentrate obtained, the means described in the left (cooling rotating cylindrical ice generator + separation unit) is repeated (the concentrate obtained by each means is used as a stock solution of the next means, and each means repeated Increasing the concentration of the concentrate by decreasing the cooling rotational cylinder temperature of the sequential cooling cylinder ice generator) and further reducing the concentration of SO ₄ ions in the concentrate (while further reducing the Na ion) Can. When Na ₂ SO ₄ ··· ₁₀ H ₂ O is mixed in the concentrated solution in the step on the left, the mixed Na ₂ SO ₄ ·· ₁₀ H ₂ O may be removed by precipitation in a cooling tank or the like.

The reduction of SO ₄ ion concentration by the method of the present invention in the concentration of seawater suppresses the precipitation of Ca 2 SO ₄ to obtain a concentrate rich in Ca ions (the intake of which is required for health maintenance) It becomes possible. Also, precipitation of Na ₂ SO ₄ .10H ₂ O reduces Na ions in the concentrate. Furthermore, since concentration by freezing enables uniform concentration of solutes, a natural mineral liquid excellent in mineral balance (the mutual ratio of essential mineral components) can be obtained.

For manufacturers of beverages and processed foods, natural mineral liquids containing no additives are desired. Further, (beverages and processed foods, etc. in) Ca SO ₄ is precipitate, create problems of cloudiness and taste change, no mineral solution of Ca SO ₄ (or modestly less Ca SO ₄₎ is desired.

  In addition, in order to manufacture processed foods (miso, soy sauce, etc.), generally, salt water having a salt concentration of 10 wt% or more is required.

The natural mineral liquid produced by the method of the present invention is not limited to human use for beverages (including medical use) and processed foods etc. Use as a natural additive to feeds for various animals (including aquatic products), etc. Moreover, utilization to the pharmaceuticals etc. by component separation of this natural mineral high concentration liquid is also considered.

Patent Document 1 is a patent for concentration of seawater and removal of SO ₄ ions using an RO membrane and an NF membrane. Among them, the contents of SO ₄ ions in the low concentration concentrated solution treated in the order of the NF membrane and the RO membrane are shown as a table. When the concentrate obtained by the NF membrane and the RO membrane was concentrated by removing only water, the concentration of SO ₄ ions was increased, and the concentration was reduced by freezing to reduce the concentration of SO ₄ ions. The decrease in SO ₄ ion concentration at time (when the cooling temperature is lowered) crosses over time. When the intersection of the above two methods is determined based on the Ca ion concentration, the intersection becomes about 0.27 wt% of Ca ion concentration and about 0.21 wt% of SO ₄ ion concentration. The salt concentration in the freezing method at this intersection is about 22 wt% and the freezing point is about -18 ° C.
Furthermore, in the freezing method, the concentration of SO ₄ ions in the concentrate can be set to 1/2 or less as compared with the above-mentioned crossing point.

Incidentally, freezing seawater salinity of about 25 wt% (freezing point -23 ° C.) in NaCl · _{2 H} 2 O and start to precipitate (the NaCl concentration in the solution to decrease the wake of the temperature decreases rapidly). Concentration by evaporation starts to precipitate NaCl at a salt concentration of about 26 wt%. Precipitation of NaCl (or NaCl · 2H ₂ O ) using the present invention can be carried out by evaporation of the concentrated liquid obtained by the method of the present invention and the present invention, etc., and NaCl (or NaCl · 2 H ₂ O ) The separation of the concentrated mineral solution containing Ca and the like after precipitation and the palatability salt and the like can be performed by centrifugation, evaporation and the like.

  The method of the present invention also has the advantage of not requiring (or simplifying) filtration equipment, such as suspended organics, in the concentration of seawater (causing the loss of throughput in the method using membranes).

The method of the present invention can also be used for the solution after various membrane (RO membrane, NF membrane, electrodialysis membrane, etc.) treatment.
For example, in the case of concentration of seawater, Ca SO ₄ is deposited by the RO membrane (precipitation of Ca SO ₄ makes it difficult to use the film) and concentrated to a concentration below (e.g. salt concentration 6 wt% or less), then the resulting concentrated The solution can be concentrated to a high concentration by the method of freezing of the present invention. In this case, since the RO membrane treatment can be performed at a low pressure, the concentration operation including freeze concentration of this method is an energy-saving method.
Moreover, NF membrane processing and electrodialysis membrane processing can change the mutual ratio of the solute concentration in a solution with the processing time and the kind of membrane (nonpatent literature 13). For this reason, NF membrane treatment and electrodialysis membrane treatment obtain a solution in which mutual ratio of solute concentration in solution is changed, and concentrate the solution in which mutual ratio of solute concentration is changed using freeze concentration of this method. Can. For example, a solution of Ca / Mg of about 1 to 2 (hereinafter Ca / Mg represents a weight ratio of Ca and Mg) is obtained from seawater (including deep ocean water) using electrodialysis membrane treatment, and the solution is The freeze concentration of the method can be used to obtain a Ca / Mg of about 1 to 2 and a Ca-rich concentrate. It is always good that Ca / Mg is around 1 to 2 for the intake of Ca by beverages and foods, and it will prevent rapidly increasing ischemic heart disease (myocardial infarction etc) and arteriosclerosis etc. Patent documents 6, 8).

Yuuki Toyoda, Master's Thesis, Kochi University of Technology 2003

The apparatus of the present invention may be installed in a low temperature maintained cooling chamber.
In addition, when the apparatus and method of the present invention are used in an atmosphere of 0 ° C. or higher (in particular, in a region where outdoor temperature is high, or in a period), melting of ice in the ice liquid mixture during separation in the separation part is considered. In this case, it is possible to solve this problem by increasing the proportion of ice in the ice-liquid mixture in the ice-generating part in the operation of the apparatus (for example, the ice-liquid proportion of the ice-liquid mixture in the ice-generating part is 9: 1 And). Patent Document 2 describes improvement of separation efficiency by melting of ice using a heater of the ice liquid mixture being separated in the separation portion of the ice liquid mixture of the freeze concentrator. For this reason, the height of the ambient temperature does not become a factor to reduce the separation efficiency of the ice liquid mixture of the present method.

U. S. Pat No. 6387253

  The device of the present invention is not limited to a specific size in various applications and fields of application, and may have various sizes.

  The device of the present invention is easy to mount on a movable body such as a car body and a hull because the structure and operation of the device and the equipment constituting the device are simple.

The method of freeze concentration according to the present invention can obtain a concentrated solution of high concentration, continuously treats a large amount of concentrated solution (or diluted solution of solute concentration) in a short time, and costs apparatus cost relative to throughput It is cheap and excellent in the mobility of the device (the start up to steady operation is quick at startup, and intermittent operation of several hours is also possible). In addition, it is possible to prevent the mixing of ice into the concentrate.
Further, by using the method of the present invention to high concentrations concentrated seawater (Ca deposition of SO ₄ was suppressed) rich viewing including the Ca ions, also excellent mineral balance (Ca / Mg ≦ 1 to 2 and essential minerals Of natural mineral concentrates , which are excellent in the mutual ratio of Na) and Na ions, and can produce new salts.

FIG. 1 is a schematic view of a cooled rotating cylindrical ice generator of the present invention. FIG. 2 is a schematic cross-sectional view of the same vertical differential speed scraping blade separator.

  The cooling rotary cylinder ice generator 1 of FIG. 1 comprises a cooling rotary cylinder 11 for generating an ice liquid mixture 1a, a rotary cylindrical scraping blade 13 for peeling the ice liquid mixture 1a from the cooling rotary cylinder, and a circumferential lower portion of the cooling rotary cylinder. Is an ice generator stock solution tank 12 provided so as to be immersed in the stock solution (concentrated solution). A chiller circulating a freon refrigerant for cooling the inner surface of the rotating cylinder is pipe-connected to the cooling rotating cylinder 11. Hereinafter, the operation of the ice generator 1 will be described. The stock solution from the stock solution tank is sent to the ice generator stock solution tank 12 of the ice generator 1. A liquid level sensor (e.g., float) is attached to the ice producing machine stock solution tank 12, and the amount of liquid in the tank 12 is maintained (by the supply of the stock solution from the stock solution tank). Freezing of the stock solution takes place on the outer circumferential surface (cooling surface) of the rotating cooled rotating cylinder 11. When the rotating cooling surface is immersed in the solution in the ice generator stock solution tank 12, ice crystals are generated on the cooling surface and an ice-liquid mixture is formed on the cooling surface. The formed ice liquid mixture is separated from the solution in the ice generator stock solution tank as the cooling rotary cylinder 11 rotates, and ice crystals in the ice liquid mixture grow. The ice-liquid mixture formed on the cooling surface is cooled by the rotating cylindrical scraping blade 13 positioned in the opposite direction on the circumference (at the ice-producing machine stock solution tank level separation point of the ice-liquid mixture by rotation). It is continuously peeled off from the outer surface and discharged to the outside of the cooled rotating cylindrical ice generator 1 by natural fall.

The ice-liquid mixture 2a generated by the above-mentioned ice generator 1 is sent to the vertical differential speed scraping blade separator 2 (FIG. 2) located below the ice generator 1.
The vertical differential speed scraping blade separator 2 is a high speed rotating porous wall basket 20, a high speed rotating porous wall basket 20 attached to the inside of a porous screen rotating integrally with the high speed rotating porous wall basket 20, the screen And an attached ice scraping blade 22 which rotates together with the high speed rotating porous wall basket close to the inner wall of the separator housing. The operation of the vertical differential speed scraping blade separator 2 is as follows. The ice liquid mixture 1a from the cooled rotating cylindrical ice generator 1 is introduced into the bottom of the high speed rotating porous wall basket 20 by free fall. The introduced ice liquid mixture 1a is spread by centrifugal force on the screen surface inside the high speed rotating porous wall basket 20. The spread ice liquid mixture 1a is moved upward by the differential speed scraping blade 21 which rotates close to the screen (rotating differentially with the rotation of the high speed rotating porous wall basket 20) high speed rotational centrifugal force Separate the liquid (concentrate) 2b in the ice-liquid mixture 1a from the ice-liquid mixture 1a (the liquid 2b will pass through the screen and the holes of the high-speed rotating porous wall basket 20). The separated ice 2a from which the ice-liquid mixture 1a is drained is discharged from the upper end of the high-speed rotating porous wall basket 20 through the attached ice scraping blade 22 to the outside of the vertical differential-speed scraping blade separator 2.
The separated ice 2a discharged is placed in a separation ice tank located below the vertical differential speed scraping blade separator 2. On the other hand, the concentrate 2b is sent to a concentrate tank.

The application of the present invention is the production of various concentrations of concentrated natural mineral concentrates ( rich in Ca ions, low in Ca / Mg ≦ 1-2 and Na ions ) from seawater (and deep sea water), left There are production of a highly palatable salt containing components, treatment of waste liquid where low boiling point harmful substances are mixed into evaporation water in concentration and evaporation concentration of a solution containing a target substance (protein etc.) in bioresearch etc.

DESCRIPTION OF SYMBOLS 1 cooled rotating cylindrical ice generator 11 cooled rotating cylinder 12 ice generator stock solution tank 13 rotating cylindrical scraping blade 1a ice liquid mixture 2 vertical differential speed scraping blade separator 20 basket of porous walls rotating at high speed 21 differential speed scraping Blade 22 Adhering ice scraping blade 23 Passing fluid chamber 24 Form passing fluid chamber Clearance separating high speed rotating porous wall basket and stationary fixed wall of separator 2a Separated ice 2b Concentrate

Claims (4)

Ice-liquid mixture from a stock solution to a cooling rotating cylinder outer surface to form a cooling rotating cylindrical ice generator for discharging scraped by a rotating cylinder scraper blade the ice-liquid mixture,
The discharged ice liquid mixture is introduced into a high speed rotating porous wall basket, and the input ice liquid mixture is placed on the screen surface attached to the inside of the high speed rotating porous wall basket by a differential speed scraping blade. At the same time, the concentrate is separated from the ice-liquid mixture through the screen and the porous wall of the high-speed rotating basket by the rotational centrifugal force of the high-speed rotating porous wall basket. It comprises a differential speed scraping blade separator which discharges the separated separated ice to the outside through the attached ice scraping blade for preventing the mixing of the separated ice into the concentrate .
An apparatus for producing the concentrate or the separated ice. From seawater or seawater treated seawater using an RO membrane, an NF membrane and an electrodialysis membrane, a mixture of concentrated liquid, separated ice and Na ₂ SO ₄ · 10H ₂ O is formed on the outer surface of a cooled rotating cylinder, and the mixture is rotated A cooled rotating cylindrical ice generator scraped and discharged by a cylindrical scraping blade;
It consists of a separation part which separates this mixture into a concentrate and separation ice and Na ₂ SO ₄ .10H ₂ O ,
The salinity of the concentrate 10 wt% or more, the concentrate was further the Ca / Mg ≦ 1 to 2, or device for producing the separation of ice. A method of producing a concentrate or separated ice using the device according to any one of claims 1 and 2. A method of producing salt and concentrate from the concentrate produced in claim 3 using evaporation and centrifugation.

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