JPH03188902A - Pressurized freeze concentrator - Google Patents

Abstract

PURPOSE:To uniformize the meltability of an ice crystal passing through a pressurizing cylinder in the radial direction of the cylinder and to prevent the leakage of a concd. liq. due to the melting of the ice crystal in the vicinity of a tractor by providing an appropriate number of heat radiating blades protruding inward from the inner wall of the cylinder. CONSTITUTION:The pressurizing cylinder 12 having a downward tapered hole is connected to the lower part of a vertical cooling cylinder 4 having a mother liquor vessel 2 at its upper part through an insulating cylinder 10. A discharge pipe 16 for recovering a concd. liq. is connected to the upper part of the hole, and an endless tensile wire 8 for dragging the ice crystal 6 is circulated downward through the mother liquor vessel 2, cylinder 4, insulating cylinder 10 and pressurizing cylinder 12. In this case, an appropriate number of heat radiating blades 14a, 14e,... protruding inward from the inner wall of the pressurizing cylinder 12 are provided. Consequently, the meltability of the ice crystal passing through the pressurizing cylinder is uniformized in the radial direction of the pressurizing cylinder, the leakage of a concd. liq. due to the melting of the ice crystal in the vicinity of the tractor is prevented, and the concd. liq. is efficiently formed without reducing the velocity of the tractor.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a pressurized freeze-concentrator for producing various beverage liquids, medicinal liquids, or other concentrated liquids.

[Prior art] A solution consisting of a solute and a solvent (water) is temporarily frozen to form ice crystals, and by pressurizing the ice crystals, a solution with a high solute concentration is separated from the ice crystals and a concentrated liquid is obtained. So-called pressurized freeze concentrators have been known for some time.

In these devices, the solidification point (freezing point) of the solution is
It takes advantage of the physical phenomenon that the concentration of solute relative to water (water) changes depending on the pressure applied to the solution.

For example, in the case of an aqueous solution, pressurization lowers the freezing point, and a high concentration of solutes contained in the aqueous solution also lowers the freezing point.

FIG. 4 shows a system diagram of the previous apparatus, and the raw material liquid 32 injected into the mother liquid container 31 by the pump P naturally falls into the cooling cylinder 33.

A certain jacket 3 is attached to this cooling cylinder 33.
The raw material liquid 32 is cooled and frozen by the circulating cooling medium 3θ which enters from the inlet 34t1 of No. 4 and exits from the outlet 34b, and becomes ice crystals 36.

The ice crystals 36 are pulled downward by a pulling body 37, pass through the heat insulating part 35, and are press-fitted into a pressurizing cylinder 38 having a tapered hole with a narrowed lower part, and are pressurized.

Furthermore, a cooling medium 40 having a temperature slightly higher than that of the cooling medium 39 that enters from the inlet 41a of the jacket 41 provided in the pressurizing cylinder 38 and is discharged from the outlet 41b and circulates.
As a result, the ice crystals 36 are heated and the hardness of the ice is lowered. As a result, the concentrated liquid 44 having a higher solute concentration than the ice crystals 36 is melted and separated, and flows out through the pocket 42 into the discharge pipe 43.

However, in the above-mentioned apparatus, when the temperature of the cooling medium 40 is increased for the purpose of increasing the speed of the ice crystals 38 passing through the pressurizing cylinder 38 and increasing the processing speed, the thermal conductivity of the ice crystals themselves is poor. Due to differences in the residence time distribution of ice crystals in the first-order phase transition state within the pressure cylinder, the ice crystals near the pulling body 37 melt faster than those near the inner wall surface of the pressure cylinder 38. The concentrated liquid 44 will leak into the receiving tank 45. Conversely, if the temperature of the cooling medium 40 is lowered, the ice crystals 3B will not melt sufficiently, the pressure of the ice crystals 36 will increase, the speed of the ice crystals 36 passing through the pressurizing cylinder 38 will decrease, and the processing capacity will decrease. This will result in a significant decline.

[Objective of the present invention] The present invention aims to prevent leakage of concentrated liquid due to melting of ice crystals near the arch body by making the melting degree distribution of ice crystals passing through the pressurizing cylinder uniform in the radial direction of the pressurizing cylinder. At the same time, it is possible to provide a pressurized freeze-concentrator with high throughput that effectively generates concentrated liquid without reducing the ice crystal pulling speed of the pulling body.

[Means for Solving the Problems] In order to solve the above problems, the pressurized freeze concentrator of the present invention has a tapered hole with a narrowed bottom in the lower part of a vertical cooling cylinder having a mother liquor container in the upper part. A pressurized cylinder with It is a device that passes through an insulating cylinder and a pressurizing cylinder from above to below, and has a structure in which an appropriate number of inwardly protruding heat radiating blades are provided on the inner wall of the pressurizing cylinder.

[Function] The ice crystals frozen in the cooling cylinder are pulled downward by the tensile wire and forced into the pressurizing cylinder. The ice crystals are uniformly semi-melted by a heat dissipation blade provided on the inner wall surface of the pressurizing cylinder, and are further moved downward and pressurized. As a result, the high-concentration solute liquid within the ice crystals is squeezed upward from the bottom of the pressurizing cylinder and flows out as a concentrated liquid from the discharge pipe.

[Example] Examples of the present invention will be described in detail below using FIGS. 1 to 3.

Fig. 1 is a system diagram of this device, and in the figure, a cooling cylinder 4 is provided below a mother liquid container 2 that temporarily stores a raw material liquid 3, which is an aqueous solution containing dissolved solutes. There is. A jacket 5 is provided to surround the cooling cylinder 4 in the circumferential direction, and a cooling medium 7 is injected into the jacket 5 from an inlet 5a by a pump (not shown). The circulating cooling medium 7 is discharged from the outlet iib.

At the bottom of the cooling cylinder 4, a pressurizing cylinder 12 is installed.
Two-part flange 11 and lower flange 9 of cooling cylinder 4
and are connected to sandwich the heat insulating cylinder lO.

As shown in FIGS. 2 and 3, this pressurizing cylinder 12 has a tapered hole whose inner wall surface is narrowed at the lower part, and furthermore, the inner wall surface has blades 14a protruding toward the center at intervals of 45".
14h is provided.

Each of these blades has a double edge 19 on its second portion, and the inward facing surface 20 of each blade is vertical. Further, the protrusion width of the blades i4a, 14c, 14e, and 14g from the inner wall surface of the pressurizing cylinder 12 is shorter than the protrusion width of the blades 14b, 14d, 14f, and +4h on both sides thereof. It has become. The gap 21 surrounded by the inward facing surface 20 of each of these blades does not impede the movement of the chain 8, which is an endless pulling body that passes vertically through the center of the device. The chain 8 is moved from both sides at a speed of about 20 mm per minute by a motor (not shown).

A concave pocket 15 for a liquid reservoir is provided on the upper part of the inner wall of the pressurizing cylinder 12.
A discharge pipe 16 is connected to this hole 15.

Further, this pressure cylinder 12 has a built-in jacket 13 surrounding it in the circumferential direction, and a cooling medium 17 is injected into this jacket 13 from an inlet 13a by a pump (not shown), and further inside this jacket 13. is circulated and discharged from the outlet 13b. A tank 18 for receiving treated ice crystals is provided below this pressure cylinder 12.

Next, the processing functions of each part of this device will be explained in detail below.

The raw material liquid 3 is poured into the container 2 by the pump 1, and the raw material liquid 3
falls freely from the container 2 into the cooling cylinder 4.

Since the cooling medium 7 circulating in the jacket 5 of this cooling cylinder 4 is cooled to -30 to -15°C,
Heat energy is taken away from the raw material liquid 3 passing through the cooling cylinder 4.

As a result, the raw material liquid 3 freezes in a cylindrical shape centering around the chains 8 and becomes ice crystals 6.

This ice crystal 6 is pulled by the descending chain 8 and is moved to the heat insulating cylinder 10.
and is press-fitted into the pressurizing cylinder 12.

The temperature circulating in the jacket 13 of this pressure cylinder 12 is 2 to 5.
The ice crystals 6 passing through the pressure cylinder 12 are heated by the cooling medium 17 at a temperature of 0.degree. C., and the hardness of the ice crystals is reduced.

In addition, since the blade 14 provided on the inner surface of the pressure tube 12 conducts heat quickly in the radial direction of the ice crystals, the pressure tube 12
The entire ice crystal 6 in the container 2 is heated uniformly, and the ice crystal 6 melts uniformly and has a low freezing hardness.

Further, the ice crystals 6 that are pulled from above by the chain 8 and press-fitted into the tapered hole of the pressurizing cylinder 12 have a high ice crystal internal pressure at the lower part, and a low ice crystal internal pressure at the upper part.

By the way, the higher the pressure or the higher the solute concentration, the lower the freezing point of the ice crystals 6. As the ice crystals 6 passing through the pressurized cylinder 12 move downward, the solution with a high solute concentration becomes ice crystals. It is sequentially melted and separated from 6 and squeezed upward where the pressure is low, and flows into pocket 15.

The concentrated liquid flowing into this pocket 15 flows out to a tank (not shown) through a discharge pipe 16 and is stored therein.

In addition, residual ice crystals 6 with a low solute concentration that have passed through the pressurizing cylinder 12
will fall into the tank 18.

The thickness of the blade 14 is not particularly limited, as long as it does not extremely impede the descending speed of the ice crystals 6 passing through the pressurizing cylinder 12 and also effectively aids heat conduction. good.

For example, the inlet diameter of the pressure cylinder 12 is 54 mm and the outlet diameter is 40 mm.
In the case of the intestine (2), the thickness of the blade 14 was approximately 10 to 12 (12). Further, in order to further increase the thermal conductivity, the blade 14 may have a structure having many small notched protrusions in the vertical direction on the surface of the blade, and the outer shape of the blade 14 may be semi-elliptic instead of trapezoidal as in the above example. It may be of any shape or the like.

Furthermore, the number of blades 14 is not limited to eight as in the above example, but may be one in which many blades are arranged vertically in tandem, or many blades are arranged in a circumferential direction. Good too.

Since the blade 14 is provided on the inner wall of the pressurizing tube 12 in this way, the ice crystals 6 passing through the pressurizing tube 12 are uniformly half-melted, so that only the ice crystals near the chains 8 are melted first. It is possible to prevent this, and also to increase the descending speed of the ice crystals 6, and it is possible to improve the processing speed for producing concentrated liquid.

[Effects of the Invention] As described above, according to the present invention, by providing the blades on the inner wall surface of the pressurizing cylinder to increase the heat conduction efficiency in the radial direction, ice crystals in the pressurizing cylinder can be made uniform. It is possible to melt the ice quickly, and it is possible to prevent water from melting and leaking only in the vicinity of the traction copper in the center of the ice crystal, and it is also possible to increase the processing speed of concentrated liquid separation.

[Brief explanation of drawings]

FIG. 1 is a system sectional view showing one embodiment of the present invention, FIG. 2 is a vertical sectional view of a pressurizing cylinder of the present invention, and FIG. 3 is a top view of the pressurizing cylinder. FIG. 4 is a diagram showing a conventional example. Fig. 10 Pump 2, fist container 3, raw material liquid 4, cooling cylinder 5φ, jacket 58, inlet 5b, outlet 6 fist, ice crystal 7, φ cooling medium 8, chain 9, Flange 10--Heat insulation cylinder +1--Flange 12...Pressure cylinder 13...Jacket) +3
a...Inlet +3b -Outlet 14--Blade +5--Pocket 16...Discharge pipe 171 Cooling medium 19...Double blade 21...Gap 18...Tank 20 Inward facing surface

Claims (1)

[Claims] A pressurizing cylinder having a tapered hole with a narrowed lower part is connected to the bottom of a vertical cooling cylinder having a mother liquid container at the top via an insulating cylinder, and a discharge pipe for recovering concentrated liquid is connected to the top of the taper hole. A device in which an endless tensile wire rod for pulling ice crystals is passed through the mother liquor container, the cylinder, the insulating cylinder, and the pressurizing cylinder from above to below, and protrudes inward from the inner wall of the pressurizing cylinder. A pressurized freeze concentrator equipped with an appropriate number of heat dissipation blades.