JPH0723757A - Device for freezing article - Google Patents

Abstract

PURPOSE:To provide a device for continuously charging articles to be frozen in a low temperature liquidized gas flowing in a low temperature liquidized gas passage to freeze the articles, capable of forming the flow of the low temperature liquidized gas in a uniform layer flow state and freezing the articles in a good state. CONSTITUTION:The characteristic of this device for continuous charging articles A to be frozen in the liquid flow of a low temperature liquidized gas C to freeze the articles comprises disposing the first weir plate 11 and the second weir plate 12 in the upper stream from a site 3 for charging the articles to prevent the liquid flow from waving at the lower edge of the second weir plate 12 on the downstream side, the first weir plate 11 and the second weir plate 12 forming rectangular passages between the weir plates and the bottom surface of the low temperature liquidized gas passage (chute 2), respectively.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a freezing device for articles, and more particularly to a device for continuously freezing small objects to be frozen such as shrimp and droplets using a low temperature liquefied gas.

[0002]

2. Description of the Related Art Conventionally, it has been practiced to immerse various articles, such as foods such as shrimp, in a low temperature liquefied gas and freeze them. As a freezing device used at this time, there is known a freezing device in which a part of a conveyor for taking out frozen products is immersed in a storage tank which stores a low temperature liquefied gas, for example, liquid nitrogen. In such an apparatus, an object to be frozen is put into a storage tank, frozen by a low temperature liquefied gas, and the frozen product after freezing is taken out of the storage tank by a conveyor.

[0003]

However, in the above-mentioned freezing device, since a part of the conveyer for taking out frozen products is in contact with the atmosphere, heat intrusion is large and the amount of low-temperature liquefied gas vaporized is large. There is a drawback that the loss of the liquefied gas becomes large, and the frozen material adheres to the conveyor and is not easily peeled off, which makes it difficult to collect the frozen material.

Therefore, the present applicant has previously proposed a device for continuously freezing an object to be frozen into a low temperature liquefied gas flowing through a low temperature liquefied gas channel. According to this apparatus, it is possible to efficiently contact the frozen object with the low temperature liquefied gas to freeze it, and reduce the loss of the low temperature liquefied gas.

As described above, when the object to be frozen is put into the liquid flow of the low temperature liquefied gas to be frozen, particularly when a small object to be frozen is frozen in a loose shape or a liquid material is frozen in a granular form. For this reason, it is necessary to prevent the objects to be frozen put into the low temperature liquefied gas from adhering to each other. That is, if the flow of the low temperature liquefied gas flowing through the flow path has turbulence, drift, ripples, etc., the frozen objects do not flow at a constant velocity in the downstream direction, so that the frozen objects collide and adhere to each other. There is a risk.

Therefore, the object of the present invention is to provide an apparatus for freezing an article which can make a low temperature liquefied gas flowing in a flow path into a stable state and freeze an object to be frozen in a good state. I am trying.

[0007]

In order to achieve the above-mentioned object, a freezing apparatus for articles according to the present invention is provided with a frozen object charging section for charging a frozen object upstream of a liquid flow in a low temperature liquefied gas channel.
A freezing apparatus for articles, each of which is provided with a separation unit for separating a low-temperature liquefied gas and a frozen product at the end of the low-temperature liquefied gas flow path, wherein the low-temperature liquefied gas flow path is formed to have a flat bottom. First, a rectangular liquid passage is formed between the bottom of the low temperature liquefied gas flow path and upstream of the frozen material feeding portion of the flow path.
The weir plate and the second weir plate are arranged at predetermined intervals in the direction orthogonal to the liquid flow, and the height of the lower edge of the second weir plate on the downstream side is higher than the height of the lower edge of the first weir plate on the upstream side. It is also characterized by being set high.

[0008]

[Operation] As described above, the first weir plate having a narrow gap with the bottom of the flow path and the second weir plate having a wider gap than the first weir plate are arranged at predetermined intervals upstream of the liquid flow. Then, by adjusting the distance between the lower edges of both dam plates and the bottom surface of the flow path to an optimum state, the low temperature liquefied gas is first adjusted to a predetermined flow rate when passing under the first dam plate, and then Rippling of the liquid surface is suppressed when passing below the second dam plate, and the liquid flows down as a substantially uniform flow in the entire flow path. Therefore, the frozen material freezes while flowing in an orderly manner along the liquid flow, and a frozen material in a good state can be obtained without sticking to each other.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will now be described in more detail based on an embodiment shown in the drawings. First, as shown in FIG. 1 and FIG. 2, the freezing device includes a gutter 2 that forms a flow path of a low temperature liquefied gas C, for example, liquid nitrogen supplied from a low temperature liquefied gas supply unit 1, and an upstream of the gutter 2. The feeding portion 3 for the frozen material A provided, the separating portion 4 provided at the end, the liquid recovery container 5 for recovering the low-temperature liquefied gas C separated by the separating portion 4, and the frozen material for receiving the frozen material B The container 6 is provided, and the low temperature liquefied gas C recovered in the liquid recovery container 5 is supplied to the low temperature liquefied gas supply unit 1
An air lift pump 7 for circulating the air is provided.

The gutter 2 is formed in a flat-bottomed type having vertical walls on both sides, and the low temperature liquefied gas C supplied from the low temperature liquefied gas supply unit 1 and the frozen material A from the charging unit 3 are sufficiently supplied. It is formed to a depth and a length that can be frozen by contacting with.

The separating section 4 is formed by arranging a large number of thin rods at intervals narrower than the size of the frozen material B to be produced and substantially parallel to the flow direction of the liquid. In addition to a large number of thin rods, a separating means such as a net may be used, but by using such a large number of thin rods, it is possible to prevent the frozen product B from being caught in the separating portion 4.

A liquid recovery pipe 5 which communicates with a liquid reservoir 8 of an air lift pump 7 is connected to the liquid recovery container 5 provided below the separating section 4, and the low temperature liquefaction recovered in the liquid recovery container 5 is connected. The gas C flows into the liquid reservoir 8 through the liquid recovery pipe 9, is lifted by the air lift pump 7, and circulates to the low temperature liquefied gas supply unit 1.

Further, the low temperature liquefied gas supply unit 1 is provided with a low temperature liquefied gas introduction pipe 10 for replenishing the low temperature liquefied gas C consumed by evaporation, and the liquid level in the supply unit 1 is substantially constant. I try to keep it.

Then, on the upstream side of the input section 3 for the frozen material A,
Between the low temperature liquefied gas supply unit 1, the first weir plate 11 and the second weir plate 11 for making the low temperature liquefied gas C flowing through the trough 2 uniform.
A barrier plate 12 is provided. As shown in FIGS. 3 to 5, the dam plates 11 and 12 include support frames 13 provided on both sides of the gutter 2 and a support plate 14 provided on the support frame 13.
The support plate 14 is composed of a rectangular weir plate 15 corresponding to the shape of the flow path supported by the support plate 14, and the support plate 14 can be moved in the direction of liquid flow by an elongated hole 13a formed in the support frame 13. The barrier plate 15 is formed so as to be movable in the vertical direction by the elongated hole 14a formed in the support plate 14.

As a result, the lower edge 15a of the barrier plate 15 and the gutter 2 are provided.
The size of the rectangular liquid passage 16 formed between the bottom plate 2 a and the bottom surface 2 a of the bolt 17 is such that the dam plate 15 and the support plate 14 are fixed to each other.
Can be set arbitrarily by loosening and adjusting the vertical position of the dam plate 15, and the distance between the first dam plate 11 and the second dam plate 12 is
It can be arbitrarily set by loosening the bolt 18 for fixing the support plate 14 and the support frame 13 to each other and adjusting the support plate 14 in the liquid flow direction.

As shown in FIG. 6, the distance between the first dam plate 11 and the second dam plate 12 formed as described above and each dam plate 11,
By appropriately setting the heights of the lower edges 11a and 12a of the twelve 12 from the gutter bottom surface 2a in accordance with the liquid flow rate and the like, the low temperature liquefied gas C is generated when passing through the liquid passage formed by the first dam plate 11. The flow rate is adjusted to a predetermined flow rate, and when passing below the second dam plate 12, the ripples on the liquid surface are suppressed, and the fluid flows in a substantially uniform flow through the entire flow path. At this time, the height of the lower edge 12a of the second weir plate 12 needs to be set higher than the height of the lower edge 11a of the first weir plate 11, and the lower edge 12a of the second weir plate 12 is required.
If the height is set to be equal to or lower than the lower edge 11a of the first dam plate 11, the above-mentioned wave-dissipating effect cannot be obtained.

Since the distance between the first dam plate 11 and the second dam plate 12 and the heights of the lower edges 11a, 12a of the first dam plate 11 and the second dam plate 12 differ depending on the flow rate of the trough 2, the depth of the liquid, the inclination of the trough 2, and the like. It is necessary to experimentally set while adjusting the position of the barrier plate 15 as described above. Only one of them, for example, the second
It is also possible to form only the barrier plate 12 so that it can be adjusted.
When various conditions such as the type and flow rate of the low temperature liquefied gas C and the feeding speed of the frozen material A are fixed in advance, the position adjusting mechanism of the dam plate 15 can be omitted.

With this structure, it becomes possible to supply a substantially constant amount of the low temperature liquefied gas C to the gutter 2 in a laminar flow state, and the low temperature liquefied gas C is thrown into the flow from the charging unit 3. It is possible to prevent the frozen objects A from colliding with each other during freezing due to fluctuations in the flow rate of the liquid, turbulent flow, uneven flow, waviness, and the like, and to agglomerate and adhere to the frozen object A, so that the frozen object A can be frozen in a good state.

The air lift pump 7 used for circulating the low temperature liquefied gas in this embodiment does not require power such as electric power, has no mechanically movable parts, and does not compress the liquid.
Since it has advantages such as good cleanability, it is suitable as a pump used in such an apparatus.

However, the air lift pump 7 supplies the pumping gas (driving gas) to the lower end of the pumping pipe which is erected in the liquid in the liquid reservoir 8 to generate bubbles, Since the liquid is lifted by the ascending force, the driving gas is ejected from the upper part of the pumping pipe together with the low temperature liquefied gas to be lifted, and the liquid surface in the low temperature liquefied gas supply unit 1 is wavy or Since air bubbles mixed in with each other are aggregated to form large bubbles and randomly foamed, in a normal flow control mechanism such as a weir or a V notch, the liquid flow supplied to the flow path (gutter 2) is wavy, frothed, or drifted. However, by disposing the first dam plate 11 and the second dam plate 12 as described above, a uniform liquid flow without waviness or foaming can be achieved even when an air lift pump is used. Obtainable.

The constitution of each part in the freezing apparatus of the present invention is arbitrarily designed in accordance with the production capacity of frozen material, the type and property of frozen material, the state of charging, the type and flow rate of low-temperature liquefied gas, and other conditions. It is possible to

[0022]

As described above, the article freezing apparatus of the present invention, when the object to be frozen is put into the liquid flow of the low temperature liquefied gas channel to be frozen, is placed upstream of the object to be frozen input section. , A first weir plate and a second weir plate that form a rectangular liquid passage with the bottom surface of the low temperature liquefied gas flow path are arranged in a direction orthogonal to the liquid flow, respectively, and below the second weir plate on the downstream side. Since the ripple of the liquid flow is suppressed at the edge, it is possible to obtain a substantially uniform laminar liquid flow. This prevents frozen objects from colliding with each other during freezing and sticking to each other, and a frozen object in a good state can be obtained.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a freezing device showing a first embodiment of the present invention.

FIG. 2 is a plan view of the same.

FIG. 3 shows the structure of the weir plate, and is shown in FIG.
It is a line sectional view.

FIG. 4 is a plan view of the same.

FIG. 5 is a side view of the same.

FIG. 6 is a front view for explaining the action of the barrier plate.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Low temperature liquefied gas supply part, 2 ... Gutter, 3 ... Input part, 4 ... Separation part, 5 ... Liquid recovery container, 6 ... Frozen material container, 7 ... Air lift pump, 8 ... Liquid reservoir, 9 ... Liquid recovery pipe, 10 ... Low temperature liquefied gas introduction pipe, 11 ... 1st dam plate, 12 ... 2nd dam plate, 13 ... Support frame, 14 ... Support plate, 15 ... Dam plate, A ... Freeze object, B ...
Frozen matter, C ... Low temperature liquefied gas

Claims (1)

[Claims] 1. A freezing material feeding part for charging a frozen material upstream of a liquid flow in a low temperature liquefied gas channel, and a separation part for separating a low temperature liquefied gas and a frozen material at the end of the low temperature liquefied gas channel. In the freezing device for the article, each of which is formed with a flat bottom of the low temperature liquefied gas flow path, upstream of the frozen object input part of the low temperature liquefied gas flow path, and with the bottom surface of the low temperature liquefied gas flow path. The first weir plate and the second weir plate that form a rectangular liquid passage therebetween are arranged at predetermined intervals in a direction orthogonal to the liquid flow, and the height of the lower edge of the second weir plate on the downstream side is set to the upstream side. First on the side
An article freezing device characterized in that the height is set higher than the lower edge of the barrier plate.