JP7281928B2 - Vacuum freeze-drying equipment - Google Patents

Description

The present invention relates to the technical field of vacuum freeze-drying equipment, and more particularly to technology for heating frozen particles.

In general, drying is the process of evaporating and removing water from a substance that contains water. The boiling point of water at atmospheric pressure is 100°C, and when a substance to be dried is heated to 100°C, a large amount of water evaporates. Therefore, heating a substance containing water will increase the amount of evaporation and shorten the drying time.

However, there is a drawback that substances such as foods and medicines deteriorate when heated.

Freeze-drying is a drying technique that evaporates (sublimes) and removes moisture in a frozen state. Freeze-dried at atmospheric pressure.

In a vacuum atmosphere, the boiling point is lowered, and in particular, in a vacuum atmosphere with a pressure lower than 610 Pa, water cannot exist as a liquid. In this case, the ice does not turn into water but turns into gas and moves into the vacuum atmosphere, so it is removed by evacuation. Therefore, freeze-drying in a vacuum atmosphere can achieve high-quality drying with little deterioration of the structure and components caused by the liquid phase.

When freezing and vacuum-drying a raw material liquid in which solids are dissolved or dispersed in the liquid, droplets are generated by spraying the raw material liquid from the spray port of the nozzle into a vacuum atmosphere in order to obtain a higher quality dry powder. Then, spray freeze-drying can be used in which the frozen powder is dropped onto a tray device by self-freezing of the droplets, and the solid water contained in the frozen powder is vaporized to obtain a dry powder. There is a problem that the liquid adheres to the tip of the nozzle and freezes, blocking the spray port.

In addition, after the spraying is completed, the raw material liquid tends to remain between the valve and the spray port, and if the remaining raw material liquid freezes, the nozzle is blocked.

Furthermore, if the raw material liquid remaining between the valve and the spray port leaks from the spout and freezes, the spout will be blocked by the freeze-dried product.

Japanese Patent No. 5230033

SUMMARY OF THE INVENTION The present invention has been created to solve the above-described problems of the prior art, and an object of the present invention is to provide a technique for eliminating clogging of the spray port.

The present invention was created to solve the above-mentioned problems of the prior art, and an ice-making chamber in which a vacuum atmosphere is formed and a raw material liquid source in which a raw material liquid in which a substance to be dried is dissolved or dispersed are arranged. and a nozzle through which the raw material liquid supplied from the raw material liquid source enters the through hole from the inlet and is sprayed into the ice making chamber from the spray opening, and is sprayed into the vacuum atmosphere in the ice making chamber. A vacuum freeze-drying apparatus for forming frozen powder by freezing droplets of the raw material liquid, and drying the frozen powder, the vacuum freeze-drying apparatus having an ejection port for ejecting a cleaning gas in a direction of the introduction port. It is a vacuum freeze-drying device.
In the present invention, a cleaning gas source in which the cleaning gas is arranged and a cleaning liquid source in which the cleaning liquid is arranged are connected to the ejection port, and the cleaning liquid is ejected from the ejection port toward the introduction port. A vacuum freeze-drying apparatus configured to
The present invention is a vacuum freeze-drying apparatus in which the introduction port and the ejection port are arranged in a front chamber portion into which the raw material liquid supplied from the raw material liquid source enters the introduction port.
The present invention is a vacuum freeze-drying apparatus in which the ejection port is arranged at a position close to and facing the introduction port.

By flowing the cleaning gas, even if the raw material liquid remains between the valve and the spray port, the remaining raw material liquid can be removed before it freezes. Therefore, the space between the valve and the spray port is not clogged by frozen deposits.

Further, when the material liquid leaks out from the spout and freezes after spraying, the frozen deposits can be blown off by the cleaning gas, so that the spout will not be clogged with the frozen deposits.

Furthermore, even if the cleaning liquid is frozen, it will be automatically removed by drying after a certain period of time. Therefore, if the cleaning liquid is used to remove the raw material liquid, even if the cleaning liquid remains, the inside of the nozzle and the spray port will not be clogged. never

However, if the cleaning liquid in the nozzle is removed by using the cleaning gas after cleaning with the cleaning liquid, the cleaning liquid can be removed before the cleaning liquid freezes. There is no need to wait for the cleaning liquid to dry off.

A diagram for explaining the outline of the vacuum freeze-drying apparatus of the present invention. Diagram (1) for explaining the inside of the vacuum freeze-drying device Diagram (2) for explaining the inside of the vacuum freeze-drying device (a): Diagram for explaining the nozzle and its neighborhood (b): Diagram for explaining the front chamber and its neighborhood Diagram for explaining frozen deposits A diagram for explaining another example of the ice making chamber used in the present invention. A diagram for explaining the front chamber of the ice making chamber and its vicinity.

Reference numeral 2 in FIG. 1 indicates a vacuum freeze-drying apparatus as an example of the present invention.

This vacuum freeze-drying apparatus 2 has an apparatus main body 20 and a control device 5 .

The apparatus main body 20 includes a transfer chamber 17, a loading/unloading chamber 18, one or a plurality of ice making chambers 11A and 11B (two here), and one or a plurality of heating chambers 12A and 12B (two here). ) and

The loading/unloading chamber 18, the ice making chambers 11A and 11B, and the heating chambers 12A and 12B are arranged around the transfer chamber 17 and connected to the transfer chamber 17 via gate valves 40, 41A, 41B, 42A and 42B, respectively. there is

When the gate valves 41A and 41B between the ice making chambers 11A and 11B and the transfer chamber 17 are closed, the atmosphere inside the ice making chambers 11A and 11B and the inside atmosphere of the transfer chamber 17 are separated, and when they are opened. The internal atmosphere of the ice making chambers 11A and 11B and the internal atmosphere of the transfer chamber 17 are connected.

When the gate valves 42A and 42B between the heating chambers 12A and 12B and the transfer chamber 17 are closed, the atmosphere inside the heating chambers 12A and 12B and the atmosphere inside the transfer chamber 17 are separated and opened. Then, the internal atmosphere of the heating chambers 12A and 12B and the internal atmosphere of the transfer chamber 17 are connected.

If the internal atmosphere of the ice making chambers 11A and 11B and the internal atmosphere of the transfer chamber 17 are separated, or if the internal atmosphere of the heating chambers 12A and 12B and the internal atmosphere of the transfer chamber 17 are separated, the ice making chambers 11A and 11B are separated. The internal atmosphere and the internal atmosphere of the heating chambers 12A, 12B are separated.

Cold trap chambers 13A, 13B, 14A and 14B are connected to the ice making chambers 11A and 11B and the heating chambers 12A and 12B, respectively. 15A, 15B, 16A and 16B are arranged respectively.

The cold trap devices 15A, 15B, 16A, 16B are connected to refrigerators 35A, 35B, 36A, 36B, respectively, and are cooled by the refrigerators 35A, 35B, 36A, 36B.

The transfer chamber 17, the ice making chambers 11A and 11B, the heating chambers 12A and 12B, and the loading/unloading chamber 18 are connected to evacuation devices 21 to 24, respectively.

When the respective gate valves 40, 41A, 41B, 42A and 42B are closed and the evacuation devices 21 to 24 are operated, the internal atmosphere of the transfer chamber 17, the internal atmosphere of the loading/unloading chamber 18, and the internal atmosphere of the ice making chambers 11A and 11B are heated. The internal atmospheres of chambers 12A and 12B are evacuated.

FIG. 2 is an internal schematic diagram for explaining the insides of the transfer chamber 17, the ice making chambers 11A and 11B, and the heating chambers 12A and 12B.

The loading/unloading chamber 18 is provided with a door 45 that separates the atmospheric atmosphere from the loading/unloading chamber 18 . The tray device 8 is carried in and placed inside the loading/unloading chamber 18 .

When a predetermined number of tray devices 8 are placed in the loading/unloading chamber 18, the door is closed and the interior of the loading/unloading chamber 18 is evacuated. A plurality of tray devices 8 may be arranged in the loading/unloading chamber 18, or one tray device 8 may be arranged.

A transfer robot 19 is arranged inside the transfer chamber 17 .

The transport robot 19 has a motor 46 , a rotating shaft 43 attached to the motor 46 , and an arm 39 attached to the rotating shaft 43 , and the tray device 8 is placed on the tip of the arm 39 . The motor 46 is controlled by the control device 5 to rotate the rotary shaft 43, rotate and extend the arm 39, and move the tray device 8 arranged at the tip of the arm 39. FIG.

After the inside of the loading/unloading chamber 18 in which the tray device 8 is arranged is made into a vacuum atmosphere, the gate valve 40 between the loading/unloading chamber 18 and the transfer chamber 17 is opened, and one tray device 8 is moved into the loading/unloading chamber 18 by the arm 39 . The gate valve 40 is closed, the gate valve 41A or 41B between the ice making chamber 11A or 11B and the transfer chamber 17 is opened, and the tray device 8 is carried into the ice making chamber 11A or 11B.

A table 25 is provided inside the ice making chambers 11A and 11B, the tray device 8 carried into the ice making chambers 11A and 11B is placed on the table 25, and the gate valve 41A or 41B is closed.

Raw material liquid sources 28A and 28B in which raw material liquids are arranged are arranged outside the ice making chambers 11A and 11B. The raw material liquid has a substance to be dried dissolved or dispersed in a solvent. For example, water is used as the solvent, and the substance to be dried includes pharmaceuticals, but the solvent is not limited to water. The substance to be dried (hereinafter referred to as solute) may be organic or inorganic.

The ice making chambers 11A and 11B are provided with one or a plurality of spray devices 4a to 4c (three in this case), and each of the spray devices 4a to 4c is provided with one nozzle 6a to 6c. there is As will be described later, a plurality of nozzles may be provided in one spray device.

FIG. 4(a) is an example of an enlarged view of one nozzle 6a to 6c and its vicinity.

Each of the spray devices 4a-4c is connected to the source liquid source 28A or 28B by source liquid pipes 31a-31c. , to the nozzles 6a-6c. The spray devices 4a to 4c of one ice making chamber 11A or 11B are connected to the same raw material liquid source 28A or 28B.

Through holes 33a to 33c are formed inside the nozzles 6a to 6c, respectively, and the raw material liquids passing through the raw material liquid pipes 31a to 31c are supplied to inlets 27a to 27c at one ends of the through holes 33a to 33c, It enters the through holes 33a to 33c through the introduction ports 27a to 27c.

In this example, as shown in FIG. 4(b), front chambers 5a-5c having a space of a predetermined volume are provided at one end of raw material liquid pipes 31a-31c, and inlets 27a for nozzles 6a-6c. 27c are arranged inside the front chambers 5a-5c, and the spray ports 26a-26c at the other ends of the through holes 33a-33c are arranged inside the ice making chambers 11A and 11b.

The pressure difference between the pressure source applied to the raw material liquid sources 28A and 28B (not shown) and the pressure when the atmosphere inside the ice making chambers 11A and 11B is evacuated is used as a driving force, and the raw material liquid pipes are installed in the front chambers 5a to 5c. The raw material liquid that has passed through 31a-31c is supplied, and after the supplied raw material liquid fills the front chambers 5a-5c, it enters the through holes 33a-33c from the inlets 27a-27c.

The raw material liquid, which is sprayed into the ice making chambers 11A and 11B from the spray ports 26a to 26c and is initially in the form of a liquid column, is not affected by the gas existing in the interior atmosphere of the ice making chambers 11A and 11B. Due to the misalignment, tiny droplets are formed after traveling a certain distance from the spray ports 26a-26c. The material liquid sprayed in this process falls in the form of fine droplets inside the ice making chambers 11A and 11B.

A single tray device 8 arranged on a platform 25 is positioned vertically below each nozzle 6a to 6c.

Inside the ice making chambers 11A and 11B, water evaporates from the falling liquid droplets, the liquid droplets are deprived of latent heat as the water evaporates, and the liquid droplets having a large specific surface area contributing to the evaporation are sprayed. Therefore, the droplets become frozen particles while falling, and the frozen particles fall onto the tray device 8 and accumulate on the tray device 8 to form frozen powder. Reference numeral 9 in FIG. 3 indicates frozen powder.

When the raw material liquid is sprayed, the interiors of the ice making chambers 11A and 11B are continuously evacuated, and the cold trap devices 15A and 15B are cooled by the refrigerators 35A and 35B. When these water molecules come into contact with the cold trap devices 15A and 15B, the water molecules solidify and adhere to the cold trap devices 15A and 15B and are removed from the atmosphere inside the ice making chambers 11A and 11B.

Accordingly, water molecules in the gas generated from the sprayed droplets of the raw material liquid adhere to the cold trap devices 15A and 15B and are removed, so that they do not enter the evacuation device 22. FIG.

When a predetermined amount of frozen powder 9 is formed by spraying the raw material liquid, the spraying of the raw material liquid is stopped. Here, stopping the spraying means reducing the driving force that sprays into the ice making chambers 11A and 11B from the spray ports 26a to 26c. As an embodiment, a configuration is adopted to prevent the generation of a differential pressure. Specifically, by closing the valves in the raw material liquid pipes 31a to 31c, the raw material liquid existing after the valves is prevented from entering the ice making chamber. Since only the pressure of the internal atmosphere of 11A and 11B is applied, continuation of spraying by differential pressure becomes impossible. As another embodiment, as the raw material liquid levels in the raw material liquid sources 28A and 28B decrease, the pressure applied to the raw material liquid sources 28A and 28B directly flows through the raw material liquid pipes 31a to 31c without the raw material liquid intervening. There is a configuration that reaches the spray ports 26a to 26c via. In this case, by detecting a pressure rise in the internal atmosphere of the ice making chambers 11A and 11B, the applied pressure to the raw material liquid sources 28A and 28B is removed (as a result, the pressure of the entire system is equal to the internal atmosphere of the ice making chambers 11A and 11B). equal), and the spray stop process ends.

When the spraying of the raw material liquid ends or at a time in the vicinity thereof, the raw material liquid remaining in the raw material liquid pipes 31a to 31c or after the valves is caused by inertial force, gravity, surface tension, etc. 26a-26c may be ejected under ejection conditions outside the design.

In this case, the raw material liquid may adhere around the spray ports 26a to 26c. This is because the shape and properties of the spray ports 26a to 26c of the nozzles 6a to 6c are optimized under the differential pressure conditions at the time of design. The inventors presume that the balance with the surface energy in the environment will be lost, resulting in adhesion to the surroundings.

Since the raw material liquid adheres to the surroundings of the spray ports 26a to 26c and is in a vacuum atmosphere, the raw material liquid may freeze, resulting in the formation of frozen deposits. In addition, frozen deposits may grow through multiple steps. Furthermore, since the frozen substance is a substance obtained by freezing the raw material liquid, even if the solvent is sublimated by the vacuum atmosphere, the solute remains and adheres as a solid substance around the spray ports 26a to 26c, and is ejected from the spray ports 26a to 26c. Further problems may arise, such as changing the properties at the position of the liquid droplet interface, causing changes in the ejection direction and droplet diameter, and promoting the formation (or growth) of frozen deposits.

Due to the above, it may become impossible to continue production of the frozen powder 9, or the spray ports 26a to 26c may be blocked. Reference numeral 7 in FIG. 5 indicates frozen deposits blocking the spray ports 26a to 26c.

Regarding the removal of the frozen deposits 7, a cleaning gas source 38 and a cleaning liquid source 34 are arranged outside the ice making chambers 11A and 11B. cleaning liquid is stored in the

A cleaning gas pipe 37 is connected to the cleaning gas source 38, and a cleaning liquid pipe 30 is connected to the cleaning liquid source 34. The cleaning gas pipe 37 and the cleaning liquid pipe 30 are connected to the nozzles 6a to 6c, respectively. It is connected to supply gas and cleaning liquid respectively.

Here, after the cleaning gas pipe 37 and the cleaning liquid pipe 30 are merged, the branch pipes 32a to 32c are formed in the same number as the number of the nozzles 6a to 6c. 6c are connected one-to-one.

Jet ports 29a to 29c at the ends of the branch pipes 32a to 32c are arranged at positions facing the introduction ports 27a to 27c of the nozzles 6a to 6c in close proximity.

Here, the introduction ports 27a to 27c are arranged inside the front chambers 5a to 5c, the tip portions of the raw material liquid pipes 31a to 31c are inserted into the front chambers 5a to 5c, and the ejection ports 29a to 29c are the front chambers. They are arranged to face the introduction ports 27a to 27c inside the portions 5a to 5c.

Further, in the vacuum freeze-drying apparatus 2, the branch pipes 32a to 32c are connected to at least one of the raw material liquid pipes 31a to 31c or the front chamber portions 5a to 5c, and the supply of the raw material liquid is stopped. The cleaning gas supplied from the cleaning gas source 38 passes through the cleaning gas pipe 37 and the branch pipes 32a to 32c and is jetted from the jet ports 29a to 29c toward the inlet ports 27a to 27c. The cleaning liquid supplied from the cleaning liquid source 34 passes through the cleaning liquid pipe 30 and the branch pipes 32a to 32c in a state where the supply of the raw material liquid is stopped, and is directed from the ejection ports 29a to 29c to the introduction ports 27a to 27c. and is ejected. Here, the state in which the supply of the raw material liquid is stopped includes a state in which spraying is performed under a condition equal to or lower than the designed differential pressure.

The ejected cleaning gas or cleaning liquid enters the through holes 33a to 33c from the inlets 27a to 27c, passes through the through holes 33a to 33c, and closes the spray ports 26a to 26c. It adheres to, touches or collides with the object 7, and the biasing force is applied to the frozen deposit 7, and the frozen deposit 7 exerts osmotic pressure on the solidified solute, and the dissolution force and the dispersion force are blocked. The pressure of the cleaning gas or cleaning liquid filled in the front chambers 5a to 5c is applied to the entire frozen deposit 7 in this case.

The cleaning gas and the cleaning liquid are controlled by the control device 5 so as not to be jetted together. The frozen deposits 7 are separated from the nozzles 6a to 6c by the dissolving power and the dispersing power.

If the distance between the ejection ports 29a to 29c and the introduction ports 27a to 27c is in the range of 0.5 mm or more and 5 mm or less, the removal is facilitated.

It is also possible to jet the cleaning liquid one by one or all together from the inlets 27a to 27c in the nozzles 6a to 6c before the cleaning gas is jetted from the jetting ports 29a to 29c. It contacts the frozen deposit 7 through 33a-33c.

The cleaning liquid is a liquid that dissolves the frozen matter of the raw material liquid. For example, the solvent of the raw material liquid is used. When the cleaning liquid contacts the frozen matter 7, the frozen matter 7 is dissolved and removed.

The cleaning liquid is supplied to the nozzles 6a to 6c at a predetermined pressure, and the frozen deposits 7 are softened when they come into contact with the cleaning liquid, and the pressure of the cleaning liquid may separate the frozen deposits 7 from the nozzles.

Even if the frozen deposits 7 are not removed, the supply of the cleaning liquid is stopped after the cleaning liquid is jetted for a predetermined period of time, and when the cleaning gas is jetted from the jetting ports 29a to 29c, the urging force and the pressure , the remaining frozen deposits 7 are peeled off from the nozzles 6a-6c together with the residue of the cleaning liquid, and removed to open the through-holes 33a-33c.

When a plurality of nozzles 6a to 6c are provided, the cleaning liquid or cleaning gas may be supplied to each nozzle 6a to 6c one by one, or all may be supplied together.

Before the cleaning gas or cleaning liquid is ejected, the tray device 8 on which the frozen powder 9 is formed passes through the transfer chamber 17 from the table 25 inside the ice making chambers 11A and 11B by the arm 39, and is transferred to the heating chamber 12A. , 12B, and after the gate valves 42A, 42B between the transfer chamber 17 and the heating chambers 12A, 12B are closed, the frozen powder 9 is heated by the heating device and frozen. Solid water in the particles is vaporized and removed. As a result, a dry powder of the substance dissolved or dispersed in the raw material liquid is obtained on the tray device 8 .

The tray device 8 on which fine particles formed by drying the raw material liquid are placed is taken out by the arm 39, moved to the carry-in/out chamber 17, and taken out into the atmosphere.

The deposition of the frozen particles on the tray device 8 and the drying as described above are repeated to form dried matter on a plurality of tray devices 8 .

In the above example, the introduction ports 27a to 27c of the nozzles 6a to 6c are connected to different front chambers 5a to 5c. to 6c may be arranged.

As described above, the ice making chambers 11A and 11B and the heating chambers 12A and 12B are provided separately, so that the internal atmosphere of the ice making chambers 11A and 11B and the internal atmosphere of the heating chambers 12A and 12B can be separated. The ice making chamber 11A or 11B and the heating chamber 12A or 12B can be made into the same vacuum chamber, although the moisture is easily removed.

By the way, in order to continuously prevent clogging of the spray ports 26a to 26c and to continue stable production, a sequential process is executed to immediately jet the cleaning liquid and the cleaning gas from the jet ports 29a to 29c in order each time the spraying is stopped. It is desirable to As a result, the solute can be prevented from growing beyond a certain level by its dissolving power and dispersing power, and even if it has grown, it can be removed before it adversely affects production due to the biasing force. be.

Further, although the transport robot 19 is used in the vacuum freeze-drying apparatus 2, the tray device 8 may be transported by a transport device such as a belt conveyor or a pusher device instead of the transport robot 19.

In the vacuum freeze-drying apparatus 2, the transfer chamber 17 in which the transfer robot 19 is arranged is provided. 8 may be transported directly from the ice making chamber to the heating chamber by a conveying device such as a belt conveyor or a pusher device.

In the vacuum freeze-drying device 2, the tray device 8 is horizontally transported when moving from the ice making chamber 11A or 11B to the heating chamber 12A or 12B. When the device 8 is moved from the ice making chamber to the heating chamber, it may be transported vertically.

2 Vacuum freeze-drying device 5a-5c Anterior chamber 6a-6c Nozzle 7 Frozen deposit 8 Tray device 9 Frozen powder 11A, 11B Ice-making chamber 12A, 12B Heating chambers 26a to 26c Spray ports 27a to 27c Introduction ports 29a to 29c Jet ports 33a to 33c Through hole 34 Cleaning liquid source 38 Cleaning gas source

Claims (4)

an ice making chamber in which a vacuum atmosphere is formed;
a raw material liquid source in which a raw material liquid in which a substance to be dried is dissolved or dispersed;
a nozzle through which the raw material liquid supplied from the raw material liquid source enters the through hole from the inlet and is sprayed into the ice making chamber from the spray opening;
a pipe having an ejection port for ejecting cleaning gas in the direction of the introduction port;
a front chamber portion provided between the ejection port and the introduction port;
has
A vacuum freeze-drying apparatus in which droplets of the raw material liquid sprayed into the vacuum atmosphere in the ice making chamber are frozen to form frozen powder, and the frozen powder is dried,
When the raw material liquid is sprayed by the nozzle, the raw material liquid is introduced into the through hole from the introduction port in a state where the front chamber is filled with the raw material liquid,
The vacuum freeze-drying apparatus, when ejecting the cleaning gas in the direction of the introduction port, causes the cleaning gas to enter the through-hole from the introduction port in a state in which the front chamber is filled with the cleaning gas. The jet is a plurality of jets,
The inlet is a plurality of inlets,
2. The vacuum freeze-drying apparatus according to claim 1, wherein each of said plurality of ejection ports and said plurality of introduction ports is arranged in one said front chamber. a cleaning gas source in which the cleaning gas is disposed and a cleaning liquid source in which the cleaning liquid is disposed are connected to the ejection port;
3. The vacuum freeze-drying apparatus according to claim 1, wherein the cleaning liquid is ejected from the ejection port toward the introduction port. 4. The vacuum freeze-drying apparatus according to any one of claims 1 to 3, wherein said ejection port is arranged at a position facing close to said introduction port.

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