JP4016277B2 - Aqueous mixture processing method and apparatus - Google Patents

Description

  The present invention relates to a method and an apparatus for treating an aqueous mixed liquid, that is, an aqueous mixed liquid containing at least one water-soluble substance, or at least one water-soluble substance and at least one oil-soluble substance using water as a main medium.

A freezing concentration method is used for concentration of an aqueous mixture in which various substances are mixed and cannot be concentrated by heating, for example, containing a substance that is weak against heat in the mixture (for example, Patent Document 1). reference). However, in a system having a high water-soluble salt concentration, the concentration factor in freeze concentration is extremely low, making practical application difficult.
Also, it is a system that does not dislike heating, for example, when separating a water-soluble salt contained at a high concentration by a vacuum concentration method, the salt crystals adhere to the inner wall surface of the vacuum kettle, reducing the transfer of heat transfer area. I came and needed work such as cleaning.

Therefore, for example, in Japanese Patent Application Laid-Open No. 2001-9243, most of the high-concentration substances in the solution are removed by pre-treatment by membrane separation using a microfiltration membrane before freeze-concentration, and then freeze-concentration is performed at the subsequent stage. A method has been proposed (Patent Document 2). Japanese Patent Laid-Open No. 2000-24641 (Patent Document 3) condenses and separates sludge water in an ice heat storage tank by concentrating and separating it by the difference in freezing speed, and filtering the molten water generated in the ice heat storage tank. A method for separating sludge from treated water has been proposed. However, in the method using a filtration means such as a microfiltration membrane, it is necessary to limit the pore size of the filtration membrane according to the solute in the solution, and other water-insoluble mixtures such as fats and oils, solid particles, etc. If present, it was a concentration method (pre-concentration method) with a very narrow range of use, such as clogging the filtration membrane and making it difficult to put it to practical use.
JP 2000-334204 A JP 2001-9243 A JP 2000-24641 A

  Therefore, in view of such conventional problems, the present invention is not limited to the pre-treatment for freeze concentration, but is a method for treating an aqueous mixed solution in which various substances are mixed, and the solute of the high concentration aqueous mixed solution is efficiently used. It is an object of the present invention to provide a method and an apparatus for removing it. It is another object of the present invention to provide a multistage freeze concentration method using the method using the apparatus as a pretreatment for freeze concentration.

Therefore, in order to solve the above problems, the present invention provides a cylindrical container having a conical liquid outlet and a lattice-shaped member for holding crushed ice of an aqueous mixed solution in the lower part of the container. An aqueous mixed solution stock solution or a high-concentration solution previously collected by another processing apparatus is stored up to the upper position of the lattice member, and then crushed ice is dropped from the ice breaker inlet, and at least one of the solutions taken out from the liquid outlet is collected. The part is returned to the upper part of the container and sprayed onto the crushed ice, the sweating action utilizing the difference in melting speed of the crushed ice is promoted, the aqueous mixture in the crushed ice is eluted into the solution, and the crushed ice is brought to the desired concentration. All the solution accumulated at the bottom of the container is recovered, and then the whole ice melt is poured into the cylindrical container, and at least a part of the solution taken out from the liquid outlet is returned to return the entire unmelted crushed ice Spray to melt the crushed ice, and The solution collected in the bottom of the container by the solution recovered from the liquid outlet as a low concentration solution, the crushed ice is you and separating the highly concentrated solution is recovered before reduction to the desired concentration.

This is because a single crystal frozen ice has a high-concentration solution that is recovered before the crushed ice is reduced to a desired concentration by utilizing a difference in melting point between an aqueous mixed solution containing pure and solute due to a high melting point. Crushed ice is an invention for separating into a low concentration solution that is recovered after the reduced ice all melted liquid until the desired concentration is injected. In general, it is known that when the complete ice of an aqueous mixed solution is kept at a temperature higher than the melting point of the aqueous mixed solution, the contained impurities are discharged to the outside due to a phenomenon called “sweat”. Therefore, by setting the crushed ice to the temperature, a high-concentration solution containing a large amount of impurities can be taken out at first, and by melting and taking out ice containing almost no impurities, the efficiency can be improved even with a high-concentration aqueous solution. It can be well separated into a high concentration solution and a low concentration solution.
At this time, impurities are easily eluted by making the complete ice into crushed ice. Further, it has been found that the perspiration action is more effective when a solution having a higher concentration than that of pure water is sprayed. Therefore, a higher concentration solution can be recovered by spraying the high concentration solution taken out from the outlet. Moreover, it becomes possible to perform a process without increasing the amount of treated water by circulatingly using a high concentration solution.

Further, the low concentration solution taken out from the liquid outlet is subjected to a freeze concentration process utilizing a difference in freezing speed.
Thus, by incorporating the above invention as a pre-treatment of freeze concentration treatment, freeze concentration treatment can be performed efficiently and separation efficiency can be improved even for a high concentration solution containing a large amount of water-soluble salts. Is possible.

Further, as an invention of an apparatus for separating an aqueous mixed solution into a high-concentration solution and a low-concentration solution, a cylindrical container having a conical liquid outlet at the bottom of the container and a lattice-like member that holds crushed ice of the aqueous mixed solution is provided. A return means for returning at least part of the liquid taken out from the liquid outlet to the upper part of the container; and a spray means for spraying the returned liquid on the crushed ice,
A water-soluble mixed liquid stock solution or a high-concentration solution collected in advance by another processing apparatus is stored in the cylindrical container up to the upper position of the lattice-like member, and then crushed ice is dropped from the crushed ice inlet and taken out from the outlet. At least a part of the solution is returned by the returning means and sprayed on the crushed ice by the spraying means, and the aqueous mixture liquid in the crushed ice is eluted into the solution by promoting the sweating action utilizing the difference in melting speed of the crushed ice. The crushed ice is reduced to a desired concentration, and all the solution accumulated at the bottom of the container is collected, and then a total melt of ice is injected into a cylindrical container, and at least a part of the solution taken out from the outlet is returned to the container. The molten ice is sprayed onto the unmelted crushed ice by the spraying means to melt the crushed ice, and the solution accumulated at the bottom of the container by the melting is recovered as a low-concentration solution from the outlet, and the crushed ice Characterized by being configured to separate a high concentration solution to be recovered until reduced to the desired concentration.
At this time, the crushed ice may be pulverized by dropping ice into the cylindrical container from the top of the cylindrical container.

According to this invention, since the cylindrical container is used, the spray device can spray the high concentration solution evenly over the entire surface of the crushed ice, and can perform overall sweating and melting. Further, since the conical liquid outlet is provided at the bottom of the container, the liquid can be completely discharged, and the high-concentration solution is contained in the low-concentration solution and the concentration of the low-concentration solution can be prevented from increasing.
Moreover, since the lattice-shaped member is arranged at the bottom of the cylindrical container, it is possible to prevent the crushed ice from being sucked into the take-out port. Further, since the advance satisfy the high concentration solution to the upper position of the grid-shaped member, thereby preventing the ice dropping impact and noise than necessary.

Preferably, the return means is provided with means for recovering the cold heat of the high-concentration solution to be returned, and the recovered cold heat is used for freezing the aqueous mixed solution. Thereby, the thermal efficiency in this apparatus can be improved and the operating cost can be reduced.
Furthermore, a plurality of the aqueous mixed solution treatment apparatuses are provided, and the high concentration solution taken out from one apparatus is sprayed on the crushed ice in another container.
In this invention, the high-concentration solution taken out from the one apparatus is introduced into another container in advance, the high-concentration solution is filled up to the upper position of the upper lattice member of the other container, and crushed ice is added. The solution is sprayed from the spraying means. In this way, by using the high concentration solution in another container, it is not necessary to introduce a solution such as water from the outside, and the amount of treated water can be minimized.

  ADVANTAGE OF THE INVENTION According to this invention, it was possible to provide the processing method of the aqueous liquid mixture which a various substance coexists, Comprising: The method and apparatus which remove efficiently the impurity which exists in this aqueous liquid mixture. In addition, it is possible to provide a multistage freeze concentration method in which the method using the apparatus is used as a pretreatment for freeze concentration.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention unless otherwise specified, but are merely illustrative examples. Not too much.
FIG. 1 is a diagram for explaining the operation of the aqueous mixed liquid processing method of the present invention, FIG. 2 is an overall configuration diagram of the aqueous mixed liquid processing apparatus according to the present embodiment, and FIG. 3 is a processing flow of the aqueous mixed liquid processing apparatus of FIG. FIG. 4 is a diagram showing a processing flow in the case where a plurality of the aqueous mixed solution processing apparatus of FIG. 2 is provided, and FIG. 5 is a processing process diagram in the case where the aqueous mixed solution processing according to the present invention is combined with the freeze concentration processing. It is.
Although this embodiment is suitable for the process which isolate | separates SS content (suspended substance), oil content, and a solution from cutting oil waste liquid, for example, it is applicable not only to this but to any aqueous mixed liquid.

  Such an embodiment relates to a method and an apparatus using the operation shown in FIG. Using the fact that the melting point of pure water is higher than the melting point of the aqueous mixed solution containing the solute, the high-concentration solution and the low-concentration solution are separated by the difference in the melting rate of the frozen ice. In general, it is known that when the complete ice of an aqueous mixed solution is kept at a temperature higher than the melting point of the aqueous mixed solution, the contained impurities are discharged to the outside due to a phenomenon called “sweat”. As shown in FIG. 1, the aqueous mixed solution 5 stored in the tank 1 is (a) introduced into the ice maker 2 and is completely frozen by applying cold heat from the refrigerator 3, and the temperature is set higher than the melting point of the aqueous mixed solution. When kept high, the coagulated oil 8 is eluted on the ice surface and the frozen ice 6 is melted to produce a concentrated solution 7 (c). Then, by spraying the solution from the upper part of the frozen ice 6, the agglomerated oil component 8 can be washed and the concentrated liquid 7 can be taken out from the lower part (d). As a result, ice that hardly contains the flocculated oil 8 and the concentrated liquid 7 remains, and the high-concentration solution and the low-concentration solution can be efficiently separated by melting and removing the ice.

  FIG. 2 shows an apparatus that effectively uses such an action. An aqueous mixed liquid processing apparatus 10 shown in FIG. 2 includes a main body 11 including a cylindrical container 11a, a conical part 11b provided at the bottom of the container, and a liquid outlet 11c provided at the tip of the conical part. The lattice-shaped grating 12 disposed in the lower part of the container, the spray nozzle 13 and the ice breaker inlet 14 provided in the upper part of the container, the three-way valve 15, and the liquid taken out from the liquid outlet 11c are sprayed. A configuration including a return line 16 for returning to the nozzle 14, a heat exchanger 17 disposed on the return line 16, and a discharge line 18 for discharging the liquid from the liquid outlet 11c to the outside. It has become.

The cylindrical container 11a having the conical portion 11b at the bottom has its bottom end (conical apex) sealed with a liquid outlet 11c. The said container 11a is equipped with the heat exchanger 17, and the heat exchanger 17 adjusts the temperature of the crushed ice 21 of an internal aqueous liquid mixture by heat-exchanging an aqueous liquid mixture and a heat medium.
The bottom part of the cylindrical container 11a is the conical part 11b because the melted liquid can be easily separated and extracted from the outlet 11c.
In the container 11a, the crushed ice 21 is held by the grating 12 so as not to be sucked into the outlet 11c.

  The liquid discharged from the outlet 11c of the container 11a is discharged to the outside from the discharge line 18 by the three-way valve 15, or enters the container body 11 through the spray nozzle 13 through the return line 16. It is controlled to be circulated. In addition, a circulation pump for returning the liquid to the spray nozzle 13 is provided on the return line 16, and the heat exchanger 17 is arranged to recover the cold.

Next, a processing flow using the aqueous mixed solution processing apparatus 10 will be described with reference to FIG. As shown in FIG. 3, first, after storing the high-concentration solution 20 or the aqueous mixed solution stock solution in the cylindrical container 11 up to the upper position of the grating 12, the crushed ice 21 is fed from the crushed ice inlet 14 (a ). The crushed ice 21 may be crushed by a drop impact after the complete ice of an aqueous mixture is introduced from the inlet 14.
Then, the high-concentration solution 20 contained in the crushed 21 is taken out from the take-out port 11c using the difference in melting speed, and sprayed evenly on the crushed ice 21 from the return line 16 through the spray nozzle 13 (b). .

At this time, it is preferable that the cold heat of the high-concentration solution 20 is recovered by the heat exchanger 17 on the return line 16 and used as the cold heat during the production of frozen crushed ice.
By spraying the high-concentration solution 20, solutes such as oil and SS in the crushed ice 21 are eluted and washed away, and the high-concentration solution 20 collected at the bottom of the container is recovered from the outlet 11c (c).
Then, after reducing the crushed ice to a desired concentration, the ice total melt is injected (d), the low concentration solution 22 is returned by the return line 16, and sprayed on the entire crushed ice 21 from the spray nozzle 13, thereby breaking the crushed ice 21. Thaw to recover the low concentration solution 22 by melting (e).

As in this processing flow, the aqueous mixture is frozen to be denatured, and it becomes possible to elute and separate as a highly concentrated solution concentrated from aggregates by spontaneous sweating from completely frozen ice. Accordingly, even a high concentration mixed solution can be efficiently separated into a high concentration solution and a low concentration solution.
Moreover, by making the frozen ice into crushed ice 21, impurities are easily eluted. Further, by spraying the high-concentration solution 20 taken out from the outlet 11c, it is possible to further collect a high-concentration solution, and it is possible to prevent an increase in the amount of treated water by circulating the high-concentration solution. Furthermore, by providing the heat exchanger 17, the thermal efficiency can be improved, and the operating cost can be reduced.

  Moreover, the following effects are acquired by setting it as an above-described apparatus structure. That is, by making the container body 11 cylindrical, the high-concentration solution 20 can be sprayed on the entire crushed ice instead of locally. Further, since the bottom of the main body is the conical part 11b, the liquid can be taken out without remaining in the main body 11, so that the high-concentration solution 20 is mixed in the low-concentration solution 22 and the concentration of the low-concentration solution is reduced. A liquid with few impurities can be obtained without increasing.

FIG. 4 shows an embodiment in which a plurality of the aqueous mixed solution treatment apparatuses are provided. In the present embodiment, three processing apparatuses 10A, 10B, and 10C are arranged in parallel to perform processing with a time difference. Such a processing apparatus is not limited to three, and is set as appropriate in consideration of the installation area of the apparatus, the installation cost, and the like.
In the first step shown in FIG. 4A, in the processing apparatus 10A, the high concentration solution 20 or the aqueous mixed solution is stored in the empty container body 11 up to the upper position of the grating 12, and then the crushed ice 21 is introduced. On the other hand, in the processing apparatus 10 </ b> B, at least a part of the high concentration solution 20 taken out from the lower part of the apparatus 10 </ b> B is returned onto the crushed ice 21 stored in the main body 11 and sprayed from the spray nozzle 13. At this time, at least a part of the high concentration solution 20 taken out from the outlet may be branched from the three-way valve 15b and introduced into the processing apparatus 10A.

Further, the processing apparatus 10C recovers the high-concentration solution 20 by melting and recovering the crushed ice 21 containing almost no impurities by circulating and spraying the low-concentration solution 22.
Further, in the second step shown in FIG. 4B, in the processing apparatus 10A, the high-concentration solution 20 is sprayed on the crushed ice 21 held in the main body 11, and the aqueous mixed solution eluted in the crushed ice is washed away. The concentrated solution 20 is collected and at least a part thereof is returned to the spray nozzle 13.

And in the said processing apparatus 10B, the low concentration solution 22 is collect | recovered, circulatingly spraying the low concentration solution 22 on the crushed ice after collect | recovering the high concentration solution 20. FIG. In the processing apparatus 10C, after recovering the low-concentration solution 22 formed by melting the crushed ice 21 containing almost no water-soluble salt, the high-concentration solution 20 introduced from the processing apparatus 10A is introduced into the main body 11. Then put the crushed ice 21.
As described above, the treatment efficiency can be greatly improved by using a plurality of treatment devices, and the amount of treated water can be minimized by effectively using the treated water.

  FIG. 5 is a process diagram showing a concentration method in which a freeze concentration process is performed in the next stage of the aqueous mixed solution process described in the embodiment. As shown in FIG. 5, the drained liquid obtained in the aqueous mixed liquid processing step 100 using the aqueous mixed liquid processing apparatus 10, that is, the dilute low-concentration aqueous mixed liquid is freeze-concentrated into conventionally known frozen ice. The freeze concentration step 101 was performed. As a result, it was possible to perform freeze concentration even in a high-concentration aqueous mixture, and water with high purity could be separated.

  The present invention is suitably used for water treatment for separating SS components (suspended substances), oil components, and solutions from cutting oil waste liquid, but may also be applied to food industries, chemical industries, sewage treatment plants, and the like. For example, further improvement in processing efficiency can be expected by incorporating it into another system such as an existing freeze concentration processing system.

It is a figure explaining the effect | action of the aqueous liquid mixture processing method of this invention. It is a whole block diagram of the aqueous liquid mixture processing apparatus concerning this embodiment. It is a figure which shows the processing flow of the aqueous | water-based liquid mixture processing apparatus of FIG. It is a figure which shows the processing flow at the time of providing two or more aqueous liquid mixture processing apparatuses of FIG. It is a processing-process figure at the time of combining the aqueous liquid mixture process concerning this invention with a freeze concentration process.

Explanation of symbols

6 Frozen ice 7 Concentrated liquid 8 Aggregated oil content 10, 10A, 10B, 10C Aqueous liquid mixture processing device 11 Main body 11a Cylindrical container 11b Conical part 12 Grating (lattice part)
DESCRIPTION OF SYMBOLS 13 Spray nozzle 14 Ice breaking inlet 16 Circulation line 17 Heat exchanger 20 High concentration solution 21 Ice breaking 22 Low concentration solution 100 Aqueous liquid mixture processing apparatus 101 Freezing concentration apparatus

Claims (5)

In a cylindrical container having a conical liquid outlet at the bottom of the container and a lattice-shaped member for holding the crushed ice of the aqueous mixed solution, the water-soluble mixed solution is collected up to the upper position of the lattice-shaped member or collected in advance by another processing apparatus. The high concentration solution is stored, and then the crushed ice is dropped from the crushed ice inlet, and at least a part of the solution taken out from the liquid outlet is returned to the upper part of the container and sprayed on the crushed ice. The sweating action utilizing the difference is promoted to elute the aqueous mixed solution in the crushed ice into the solution, the crushed ice is lowered to the desired concentration, and all the solution accumulated at the bottom of the container is collected, and then placed in the cylindrical container Inject a total melt of ice, return at least a portion of the solution taken out from the liquid outlet, spray over the entire unmelted crushed ice, melt the crushed ice, and lower the concentration of the solution accumulated at the bottom of the container by the melting As the solution, the liquid outlet Recovered, aqueous mixture treatment method characterized in that the crushed ice is separated from the highly concentrated solution is recovered before reduction to the desired concentration. 2. The aqueous mixed liquid treatment method according to claim 1, wherein the low concentration solution taken out from the liquid outlet is subjected to freeze concentration treatment utilizing a difference in freezing speed . A cylindrical container having a conical liquid outlet at the bottom of the container and a lattice-like member that holds crushed ice of the aqueous mixed liquid is provided, and at least a part of the liquid taken out from the liquid outlet is returned to the upper part of the container Return means for spraying, and spray means for spraying the returned liquid onto the crushed ice,
A water-soluble mixed liquid stock solution or a high-concentration solution collected in advance by another processing apparatus is stored in the cylindrical container up to the upper position of the lattice-like member, and then crushed ice is dropped from the crushed ice inlet and taken out from the outlet. At least a part of the solution is returned by the returning means and sprayed on the crushed ice by the spraying means, and the aqueous mixture liquid in the crushed ice is eluted into the solution by promoting the sweating action utilizing the difference in melting speed of the crushed ice. The crushed ice is reduced to a desired concentration, and all the solution accumulated at the bottom of the container is collected, and then a total melt of ice is injected into a cylindrical container, and at least a part of the solution taken out from the outlet is returned to the container. The molten ice is sprayed onto the unmelted crushed ice by the spraying means to melt the crushed ice, and the solution accumulated at the bottom of the container by the melting is recovered as a low-concentration solution from the outlet, and the crushed ice It desired high concentration solution to be collected until the reduced concentration and separating arrangement and the possible aqueous mixture processing apparatus according to claim. 4. The aqueous mixed liquid processing apparatus according to claim 3, wherein the returning means is provided with means for recovering the cold heat of the high concentration solution to be returned, and the recovered cold heat is used for freezing the aqueous mixed liquid. 4. The aqueous mixed liquid processing apparatus according to claim 3, wherein a plurality of the aqueous mixed liquid processing apparatuses are provided, and the high-concentration solution taken out from one apparatus is sprayed on crushed ice in another container .

Images