JPH0350472A - Frozen particle manufacturing device - Google Patents

Abstract

PURPOSE:To improve cooling heat-exchanger efficiency of vaporized refrigerant gas as well as lower the height of a container and hence minimize a title device by providing a partition plate in the container for directing spirally or in a zig-zag manner lowering spray particles of a stock material to be frozen and rising vaporized refrigerant gas and bringing those particles into contact with the vaporized refrigerant gas in a counter flow. CONSTITUTION:A spiral particle plate 16 attached to the internal peripheral part of a container 1 comprises a thin plate such as a stainless and the like and has predetermined spiral turns. Falling spray particles, i.e., water droplets 14a and rising vaporized refrigerator gas 12a flow along a space of a spiral partition plate 16 and make contact with each other in a counter flow for gradual heat exchange, whereby the water droplets 14a fall finally on a mesh- shaped member 5 and is recovered. Since the rising vaporized refrigerator gas 12a and the falling water droplets 14a move long the spiral partition plate 16, there are lengthened the time or the distance for them to make contact with each other in a counter flow for satisfactory heat exchange. Thus, cooling heat exchange efficiency by the vaporized refrigerator gas is increased to yield low temperature frozen particles and hence the container 1 can be miniaturized.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an apparatus for producing frozen grains such as ice grains suitable for use as abrasive grains, abrasives, etc. for surface treatments such as blasting and cleaning. It is something.

[Conventional technology]

FIG. 4 is a vertical cross-sectional configuration diagram showing a conventional frozen grain manufacturing apparatus disclosed in, for example, Japanese Patent Application Laid-Open No. 63-91470.

In the figure, (1> is an insulated container for producing frozen grains,
(la) is a cold air outlet (2) is a means for collecting frozen grains, (3)
(4) is a refrigerant evaporative gas generating means, (5) is a mesh body, (6) is a frozen particle extraction pipe, (6a) is a valve, (
7a) is a cold gas phase region, (7b) is a refrigerant evaporative gas generation region, (8) is a sprayer, (8a) is a nozzle, (9) is a raw material supply pipe, Ql is a spray gas introduction pipe, αυ is a refrigerant supply pipe, 0 is refrigerant, (l2a) is refrigerant evaporation gas, 0 is pubbling pipe,
(14a) is the sprayed particle of the raw material to be frozen, and (14b) is the frozen particle.

Next, the operation will be explained. The container (1) is constructed as an insulated container having a cold air outlet (la) at the upper end of the peripheral wall, and the frozen particle collection means (2) is connected to a pyramid-shaped body (5) converging at the bottom and a center portion at its lowermost end. It is equipped with a vertically installed frozen particle extraction pipe (6). The mesh body (5) is attached to the inner circumferential wall of the container (1>) and divides the inside of the container (1) into an upper cold gas phase region (7a) and a lower refrigerant evaporative gas generation region (7b).

The mesh body (5) is a wire mesh that is resistant to low temperatures and has a mesh degree that allows only evaporated refrigerant gas to pass through. Spraying means (
3> is provided with a sprayer (8) at the center of the upper wall of the container (1), and a raw material supply pipe (9>) that supplies the raw material to be frozen, such as water, to the sprayer (8), and a material supply pipe (9>) that is pressurized and cooled as appropriate. A spray gas introduction pipe OO is connected to introduce a spray gas such as nitrogen gas, and water, which is the raw material to be frozen, is sprayed downward in the form of a mist from the nozzle (8a) at the tip of the sprayer (8) by the pressure of the spray gas. It is something.

The refrigerant evaporative gas generation means (4) has a refrigerant evaporative gas generation area (
7b) is supplied with a predetermined amount of refrigerant, for example, liquid nitrogen 0, from the refrigerant supply pipe Ql), and a pubbling gas such as nitrogen gas, argon gas, or dry air is injected into this refrigerant (self) from the pubbling pipe 0. By this, refrigerant evaporation gas (
12a).

In the frozen particle manufacturing apparatus configured in this way, the refrigerant evaporative gas (12a) passes through the reticulated body (5) from the refrigerant evaporative gas generation region (7b) to reach the cold gas phase region (7a), and (7a) is raised toward the cold air outlet (la).

That is, the refrigerant evaporated gas (12a) gradually rises toward the cold air outlet (1a) while generating a density difference by successively exchanging heat with spray particles of the material to be frozen, that is, atomized water droplets (14a). On the other hand, the water droplet (14a) is in the cold gas phase region (
During this time, the ice particles (14b) fall into countercurrent contact with the rising evaporated refrigerant gas (12a), gradually proceeding with heat exchange, and freeze. ) and is collected.

[Problem to be solved by the invention]

Since the conventional frozen grain production apparatus is constructed as described above, frozen grains are produced by freezing through heat exchange through countercurrent contact between the evaporated refrigerant gas and the sprayed particles. Therefore, in order to obtain low-temperature frozen particles or to perform sufficient heat exchange and increase the heat exchange efficiency of refrigerant evaporation gas, it is necessary to set the time or distance of countercurrent contact to be long. This resulted in problems such as increasing the length of αυ in the vertical direction, making the manufacturing equipment itself larger.

This invention was made in order to solve the above-mentioned problems, and it is possible to improve the efficiency of cooling heat exchange of refrigerant evaporation gas, reduce the height of the container (1), and reduce the size of the freezing device. The purpose is to obtain a grain manufacturing device.

[Means to solve the problem]

The frozen granule manufacturing apparatus according to the present invention is provided with a partition plate in a container to cause the descending spray particles of the raw material to be frozen and the ascending evaporative refrigerant gas to flow in a spiral or zigzag manner and come into countercurrent contact.

[For production]

The frozen particle production apparatus of this invention uses a spiral or zigzag partition installed in the container to allow sufficient time for countercurrent contact between the evaporated refrigerant gas and the spray particles, thereby generating heat generated by the evaporated refrigerant gas. To improve exchange efficiency and produce frozen grains at a sufficiently low temperature.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. 1st
In the figure, (self) is a spiral partition plate attached to the inner circumference of the container (1). The partition plate 0 is made of a thin plate made of stainless steel or the like, and has a predetermined number of spiral turns. In addition, if adhesion of spray particles to the partition plate αQ becomes a problem, coat the surface of the partition plate (G) with a polymeric material with poor wettability (for example, Teflon resin, etc.).
(not shown).

In the frozen particle production apparatus configured in this way, the refrigerant evaporative gas (12a) passes through the reticulated body (5>) from the refrigerant evaporative gas generation region (7b), and the refrigerant evaporative gas (12a) that has passed through the refrigerant evaporative gas (12a) passes through the reticulated body (5>).
) has a spiral partition plate (self), so this partition plate a! While rotating along 9, open the cold air outlet (la
) gradually rises in the direction of On the other hand, the spray particles (l4a) of water, which is the raw material to be frozen, are sprayed through the nozzle (8a) at the tip of the sprayer (8).
) is ejected downward in the form of mist. This spray particle (14a)
The particles also fall naturally while rotating along the spiral partition plate Q sieve.

Due to this operation, the falling spray particles, that is, water droplets (14a) and the rising refrigerant evaporation gas (12a) flow along the space of the spiral partition plate (G), and come into countercurrent contact with each other. As the heat exchange gradually progresses, water droplets (14a)
freezes. The frozen water particles (14a) eventually fall onto the net-like body (5) and are collected. Since the rising evaporated refrigerant gas (12a) and the falling water droplets (14a) move along the spiral partition plate (G), unlike the direct rising and falling motion of the conventional example, the time for countercurrent contact with each other is reduced. Furthermore, since the distance is longer, sufficient heat exchange takes place, increasing the cooling heat exchange efficiency by the refrigerant evaporation gas, producing frozen particles at a lower temperature than in the conventional case, and making it possible to downsize the container (1). is obtained.

In the above embodiment, the nozzle (8a) of the sprayer (8) is directed downward, but as shown in FIG. If the water droplets (14a) are angled so as to face the incoming refrigerant evaporated gas (l2a), the falling direction of the water droplets (14a) will be along the partition plate (c), and the degree of countercurrent contact with each other will be improved.

In addition, although the above embodiment shows the case where the spiral partition plate (T) is fixed, the cooling heat exchange efficiency can be further improved even if the partition plate (T) is rotationally driven by a motor (not shown). .

Furthermore, although the partition plates 0 were provided in a spiral shape in each of the above embodiments, as shown in FIG. (14a) may be made to flow in a zigzag pattern, and as in each of the above embodiments, the time and distance of countercurrent contact can be lengthened.

〔Effect of the invention〕

As described above, according to the present invention, a partition plate is provided in the container to cause the descending spray particles of the raw material to be frozen and the ascending refrigerant evaporated gas to flow in a spiral or zigzag pattern and come into countercurrent contact. The time and distance of countercurrent contact between the spray particles and the evaporated refrigerant gas are increased, the cooling heat exchange efficiency is increased, and the container can be made smaller.

[Brief explanation of drawings]

FIG. 1 is a perspective configuration diagram showing the inside of a frozen grain production apparatus according to an embodiment of the present invention, FIG. 2 is a perspective construction diagram showing the inside of a frozen grain production apparatus according to another embodiment of the invention, and FIG. 3 FIG. 4 is a cross-sectional configuration diagram showing a frozen grain manufacturing apparatus according to another embodiment of the present invention, and FIG. 4 is a cross-sectional configuration diagram showing a conventional frozen grain manufacturing apparatus. (l)...Insulating container, (3>...Spraying means, (8
)...Sprayer, (9)...Raw material supply pipe, Ql)...
- Refrigerant supply pipe, 0... Refrigerant, (12a)... Evaporated gas, (l4a)... Spray particles, (14b)... Frozen particles, (To)... Partition plate. , Same symbols indicate the same or equivalent parts. Agent Masuo Oiwa Figure 1: Insulating container 3: Spraying means 8: Sprayer 9: Raw material supply pipe 11: Refrigerant supply pipe 12: Refrigerant 12a: Evaporated gas 14a: Spray particles 14b: Frozen particles 15: Partition plate 2 Figure 3

Claims (1)

[Claims] an insulating container, a first supply means for supplying evaporated gas of a refrigerant into the container from the lower part of the container, a second supply means for supplying atomized particles of the raw material to be frozen into the container from the upper part of the container, and a second supply means provided in the container. . A frozen particle production apparatus comprising a partition plate that causes the descending spray particles and the ascending evaporative gas to flow in a spiral or zigzag pattern and come into countercurrent contact with each other.