JP2788570B2 - Vacuum radiation drying equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vacuum which is suitable for efficiently drying materials requiring high hygiene during drying, for example, separation membranes used in the medical field, etc., in high hygiene. The present invention relates to a radiation drying apparatus.

[0002]

2. Description of the Related Art Conventionally, dry materials that require high hygiene during drying, such as artificial kidneys used in the medical field,
When a membrane material such as an artificial lung and a plasma separator is subjected to module processing, when the water content in the membrane material is usually 1% or more,
It may cause poor potting.

[0003] Therefore, as a means for removing moisture contained in the film material, a method using continuous or batch drying with hot air, a method such as vacuum freeze-drying, and the like have been adopted.

[0004]

However, the above-mentioned hot air system requires not only a high-purity dry gas, irrespective of the circulation or one-pass system, but also the heat resistance of the substrate or the film depending on the film material. In some cases, it is not suitable for processing at a high temperature due to its structure, and there have been problems that the drying equipment is complicated and that the drying processing time is extremely long depending on the material.

[0005] In the case of vacuum freeze-drying, an object to be dried is first rapidly cooled and frozen, then decompressed and sublimated and dried under vacuum for a long time. In addition, there is a problem that the material is limited to a material whose film structure can be stabilized even at a low temperature. In addition, conventionally, an infrared emitter was used to enhance the evaporation of moisture in the drying object in a vacuum, capture and remove generated water vapor with a dehumidifying cooler, and prevent the temperature of the drying object from lowering due to latent heat of evaporation. A drying method has been proposed in which it is installed and kept at room temperature (see Japanese Patent Application Laid-Open No. 63-7771), but this method also has a problem that it takes a long time to dry.

As described above, in the conventional drying method, not only it is extremely difficult to carry out the drying in a sanitary and efficient manner, but also there are problems such as restrictions on the film material to be dried. .

[0007] In view of the above problems, an object of the present invention is to provide a vacuum radiation drying apparatus capable of performing a hygienic and efficient drying process on a material that requires a high hygiene state during drying. It is.

[0008]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention is directed to drying a dry material which requires a high hygiene condition at the time of drying. And a plurality of radiators provided at predetermined intervals in a vacuum vessel and each having a heating means. The dry material is stored between the radiators, and a vacuum state is generated by driving the vacuum pump. Under the radiant heat generated by the radiating body, it is dried by heating.

[0009]

According to the above construction, the material to be dried is heated by the radiant heat generated by the radiator in a vacuum state, so that the drying operation is performed quickly and the drying proceeds in the vacuum state. It is possible to perform an extremely hygienic drying operation without the risk of bacteria or the like entering the drying system.

On the other hand, by coating or kneading the surface of the radiator with a material having a high emissivity, the amount of radiant heat to the dried material is increased, and the drying processing time can be greatly reduced.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of a vacuum radiation drying apparatus according to the present invention will be described below with reference to FIGS.

As shown in FIG. 1, the apparatus of the present invention comprises a plurality of radiators (3) arranged at predetermined intervals inside a vacuum vessel (2) connected to a vacuum pump (1). Each of the radiators (3), (3),... Has a flow path (4) connected to a steam generator (not shown) outside the apparatus. By circulating the heating steam, radiant heat is generated from the entire surface of the radiator (3).
Further, the surface of each of the radiators (3), (3)... May be coated with a material having a high emissivity, and the amount of radiant heat applied to the dry material is reduced by such a coating. Increase. As the radiant heat generating means of the radiator (3), any heating means such as flowing a heating fluid through the flow path (4) or embedding a far-infrared heater in the radiator (3) can be used. It is possible. On the other hand, the vacuum pump (1) sucks air in the vacuum vessel (2) via a condenser (not shown).

(6) is a bogie having a plurality of supporting frames (8) (8)... Standing on a bottom frame (7), and each supporting frame (8) of the bogie (6). ), (8), ..., a plurality of dry materials (9) are suspended and supported via an appropriate support (8a). The bottom frame (7) of the cart (6) has wheels (1).
0) is mounted, and the wheels (10) travel on rails (11) laid inside and outside the vacuum vessel (2), so that the bogie (6) moves inside and outside the vacuum vessel (2). . As shown in FIG. 2, when the cart (6) moves into the vacuum vessel (2), each of the support frames (8) (8).
Is housed between adjacent radiators (3) and (3).

[0014] In the above structure, the carriage (6) suspending and supporting the dry material (9) is housed in the vacuum vessel (2),
After closing the lid (not shown) and sealing the vacuum container (2), the vacuum pump (1) is activated to start the vacuum container (2).
The inside is maintained at a degree of vacuum of about 10 Torr. On the other hand, each of the radiators (3), (3),... Is heated by the heating steam flowing through the flow path (4) and emits radiant heat from the surface to heat the dry material (9) from both sides. Therefore, the dry materials (9) (9) ...
Heating is performed in a vacuum state, and as a result, the evaporation of water is performed more quickly, and the drying time can be reduced. When a material having a high emissivity is coated on the surface of each of the radiators (3), (3)..., The amount of radiant heat applied to the dry material (9) can be increased,
Thereby, the drying time can be further reduced.

As shown in the present embodiment, the dry material (9) is suspended and supported by the support frame (8), and the carriage (6) is configured to be movable inside and outside the vacuum vessel (2). ,
A high hygienic condition is required at the time of drying, and a drying material that cannot be transported in the vacuum container (2) by an endless transport belt or the like, that is, a drying material that requires a drying operation in a non-contact state can be easily performed. .

Next, in order to confirm the effects of the present invention, an inner diameter of 330 μm, an outer diameter of 430 μm, a yarn length of 310 mm, a number of yarns of 2840 (hereinafter referred to as a bundle), and a water retention rate, which are made of a polysulfone substrate used for medical applications A 600% hollow fiber-like separation membrane is placed in the vacuum radiation drying apparatus of the present invention, and placed so that the distance between the radiator and the bundle is 30 mm, and 20 Torr.
Under a vacuum of r, the heating temperature of the radiator was set to 120 ° C., and the water retention was measured at each treatment time with an infrared moisture content measuring device. As a result, the water retention was 1% or less in 4 hours from the start of drying. Was confirmed.

In the above embodiment, a material having a high emissivity coated on the surface of the radiator using steam as a heat source of the radiator is used, for example, as follows. I'm trying to get

Primer coat: Aqueous baking coating based on TEF (ethylene tetrafluoride) resin Radiant blackbody coating: Aqueous baking coating based on TEF (ethylene tetrafluoride) resin Clear Coat: PFA (perfluoroalkoxy) resin powder-PFA has the same physical properties as TEF (ethylene tetrafluoride) resin

Coating example 1) Base treatment Sandblast treatment (# 60) 2) Primer coat The above material is spray-coated and baked at 380 ° C for 20 to 30 minutes. The primer coat is applied once. 3) Radiant black body coat The material is spray painted and fired at 380 ° C for 20-30 minutes. Radiant blackbody coating is applied twice. 4) Clear coat The above material is electrostatic powder coated and baked at 380 ° C for 20 to 30 minutes. The clear coat is applied once.

The film thickness on which the above coating is applied is 4
0 to 50 μm. The coating substance was tested by a public inspection organization and found to be "Food Sanitation Law /
Standards for foods, additives, etc. (Ministry of Health and Welfare Notification 3
No. 70) ".

For materials to be dried in fields other than the medical field and the food field, coating materials other than those described above (for example, far-infrared radiating substances such as porous alumina, etc.)
It goes without saying that can be used.

[0022]

As described above, according to the apparatus of the present invention, the drying material is heated by the radiant heat emitted from the radiator in a vacuum state, so that the drying time can be greatly reduced as compared with the case of vacuum drying alone. In addition, since the drying operation is performed indirectly and non-contactly by radiant heat under a vacuum state, dust, germs and the like do not adhere to the dried material. Therefore, it is possible to extremely efficiently and efficiently dry a dry material that requires a drying operation in a high hygiene state.

Further, by coating the surface of the radiator with a material having a high emissivity, the drying time can be further reduced.

[Brief description of the drawings]

FIG. 1 is a plan view and a side view of a vacuum radiation drying apparatus according to the present invention.

FIG. 2 is a perspective view showing a state in which a cart is housed in a vacuum container.

[Explanation of symbols]

 1 vacuum pump 2 vacuum container 3 radiator 9 dry material

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-63-7777 (JP, A) JP-A-48-62033 (JP, A) JP-A-62-158475 (JP, A) 131890 (JP, U) Shokai Sho 62-36387 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) F26B 5/04 F26B 3/28 F26B 23/04

Claims (3)

(57) [Claims] 1. A method for drying a dry material that requires a high hygiene condition during drying, comprising: a vacuum container, a vacuum pump for maintaining the inside of the vacuum container in a reduced pressure state, and a plurality of vacuum containers at predetermined intervals in the vacuum container. The drying material is housed between the radiators, and is dried by heating with radiant heat generated by the radiators under a vacuum state driven by a vacuum pump. Vacuum radiation drying equipment. 2. The vacuum radiation drying apparatus according to claim 1, wherein the surface of the radiator is coated with a material having a high emissivity. 3. A vacuum radiant drying apparatus characterized in that when drying a material having a high water content for the purpose of membrane separation, it is dried by the apparatus according to claim 1 or 2.