Vibration treatment device and treatment method using said device

Abstract

To provide a vibration treatment device comprising a microwave oscillator (magnetron), capable of meeting the demand of further purifying a treated product (reducing a permissible amount of contaminated metal, in particular).SOLUTION: There is provided a vibration dryer comprising vibration means 13 vibrating a treatment container 11. A microwave oscillation device M is attached thereto, and an output port of the microwave oscillation device M (a microwave oscillator 39) is connected to a microwave radiation unit R formed on the treatment container 11, via a flexible waveguide member 37. Further, the treatment container 11 comprises steam suction means V, with its inner surface being formed of a dielectric layer 15. When the dielectric layer 15 is formed of a polymer material, flammable polymeric abrasion powder generated is burned and extinguished.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a vibration processing device such as a vibration dryer or a vibration fluidizer, and a processing method using the device, in which the raw material fed into a processing vessel is a powder or granular material or a powder-containing raw material in a slurry or paste form. Note that the raw material (dispersoid) in the present invention is primarily a dielectric, but in the case of a drying process in which liquid components such as water are evaporated, a non-dielectric (conductor) such as a metal can also be applied, and the present invention can also be applied to a fluidized solid-state reaction. [Background technology]

[0002] Here, the vibration treatment device will be described mainly using a vibration dryer, particularly a vertical vibration dryer, as an example, but the same applies to a horizontal vibration dryer or a vibration fluidizer (for example, Patent Documents 1 and 2).

[0003] The present applicant has marketed vibration dryers such as the vertical "batch VU type," "vibration evaporator," and "vibration fluidized disperser," as well as the horizontal "batch VH type," "continuous VHC type," and "slurry feed VHS," which are capable of processing a variety of forms of raw materials, from powdered and granular materials to slurry and paste-like powdered and granular materials (Non-Patent Document 1). Patent documents relating to vertical vibration dryers filed by the present applicant include Patent Documents 3 to 6.

[0004] In these vibration dryers and vibration flow devices, microwaves can be actively irradiated into the processing vessel through a waveguide. microwave generatorThe present inventors are not aware of any apparatus equipped with a heating jacket. Patent Document 6 (Patent Document 6

[0028] ) describes that the heating means is not limited to the jacket heating of the embodiment, but that a microwave generator (magnetron) can be attached to the ceiling of the processing vessel to be used in combination with microwave heating. However, this method intends to attach the microwave generator (magnetron) directly to the ceiling, and is heterogeneous in that it is not intended to irradiate a specific portion of the raw material with microwaves from the waveguide of the present invention. Furthermore, attaching a microwave generator directly to the ceiling of the processing vessel is presumed to shorten the life of the magnetron, and has not been put to practical use.

[0005] Furthermore, Patent Documents 7 and 8 are known documents that describe microwave (reduced pressure) dryers equipped with a microwave oscillator and capable of irradiating microwaves into a drying treatment container. However, in Patent Documents 7 and 8, the treatment container is stationary, and the raw materials (materials to be dried) are all food products (vegetables, fruits, seaweed, meat, etc. (Patent Document 7 [Claim 9], Patent Document 8

[0032] ). They do not anticipate vibration treatment as in the present invention, nor do they anticipate powder or granular materials or powder-containing raw materials in a slurry or paste form. Furthermore, to uniformly irradiate the raw materials with microwaves, they require a rotating table to rotate the drying tray or a stirring fan (Patent Document 7

[0052] , Patent Document 8

[0031] ).

[0006] In view of the above, the present inventors have conceived of a vibration treatment device having the following configuration and have previously filed patent applications (Japanese Patent Application No. 2021-100522 (Japanese Patent Laid-Open No. 2022- 173013 );hereinafter referred to as the "prior application").

[0007] A vibration treatment device equipped with a vibration applying means for vibrating a treatment vessel, wherein the raw material is a powder or granular material or a powder-containing raw material in a slurry or paste form, and the vibration applying means causes the raw material introduced into the treatment vessel to flow upward and downward along the wall of the treatment vessel, The method is characterized in that a microwave transmitter is attached, the microwave emission port of the microwave generator is connected to a microwave irradiation port formed in the processing container via a flexible waveguide member, and the processing container is further equipped with a steam suction means. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-95437 [Patent Document 2] Japanese Patent Application Publication No. 7-4834 [Patent Document 3] Japanese Patent Application Laid-Open No. 2017-90029 [Patent Document 4] Japanese Patent Application Laid-Open No. 2011-7368 [Patent Document 5] Japanese Patent Application Laid-Open No. 2009-68740 [Patent Document 6] Japanese Patent Application Publication No. 11-153384 [Patent Document 7] Japanese Patent Application Publication No. 2020-190338 [Patent Document 8] Japanese Patent Application Laid-Open No. 2013-194966 [Non-patent literature]

[0009] [Non-Patent Document 1] Chuo Kakoki, "Vibration Dryer", Chuo Kakoki Catalog, p3, 6-11, June 2018 (Chuo Kakoki homepage<https: / / www.chuokakohki.co.jp> (Also available from [Non-patent document 2] Chuo Kakoki, "CORPORATE PROFILE; POWDER & CHEMICAL PLANT," Chuo Kakoki catalog, DRYER section (p10, 11), July 2017

[0010] Summary of the Invention [Problem to be solved by the invention]

[0011] The vibration treatment device described above typically consists of a steel processing vessel equipped with a heating (temperature-controlling) jacket mounted on a steel vibration table. To prevent contamination (associated with corrosion of the inner wall), at least the powder-contacting portion of the processing vessel body is made of corrosion-resistant materials such as stainless steel, Hastelloy (a Ni-based corrosion-resistant alloy: registered trademark), and titanium (Non-Patent Document 2, p. 10). These corrosion-resistant materials are all made of metals with good heat conductivity to ensure heat transfer from the jacket. To further prevent contamination, the powder-contacting portion of the processing vessel is sometimes coated with Teflon (a registered trademark), but this coating cannot be made thick enough due to the heat transfer requirements. Furthermore, the coating's low hardness makes it unsuitable for raw materials containing highly hard inorganic substances.

[0012] Furthermore, there has been a recent growing demand for stricter tolerances for contaminant content in vibration (drying) processed products (e.g., from ppm to ppb), particularly for lower tolerances for contaminants such as metal powder. This means that there is a growing demand for even higher purity (fineness) of processed products. However, the present inventors are unaware of any vibration processing device or vibration processing method that can meet this demand. While PTFE has a significantly lower coefficient of friction than other resins and is highly abrasion-resistant, it also has low hardness, and depending on the raw material (e.g., high hardness), it may be subject to scratches, making contamination unavoidable.

[0013] In view of the above, the present invention aims (problem) to provide a vibration treatment device and a vibration treatment method that can meet the demand for even higher purity of treated products (particularly, a reduction in the allowable content of metal contaminants). [Means for solving the problem]

[0014] In order to solve the above problems, the inventors focused on the microwave heating type vibration treatment device of the prior application and made intensive efforts in development, and as a result, came up with the vibration treatment device and vibration treatment method of the following configuration, in which at least the powder contact part is made of a dielectric layer that is not substantially heated by microwaves.

[0015] A vibration treatment device equipped with a vibration means for vibrating a treatment vessel, wherein the raw material is a powder or granular material or a powder-containing raw material in a slurry or paste form, and the vibration means causes the raw material introduced into the treatment vessel to flow upward and downward along the wall of the treatment vessel, a microwave generator is provided, and an output port of the microwave generator is connected to a microwave irradiation port formed in the processing vessel via a flexible waveguide member; and the processing vessel is provided with a vapor exhaust means, and at least a raw material contact portion of an inner surface of the processing vessel during operation is made of a dielectric layer; The dielectric layer is made of a material having a relative dielectric constant (ε r The fiber is characterized by being made of a polymeric or ceramic material that satisfies both of the following characteristics: a loss angle (tan δ) of 10 or less and a loss angle (tan δ) of 0.08 or less (both at a frequency of 2.45 GHz and at 25°C; the same applies below).

[0016] Here, the relative dielectric constant (ε r ) and dielectric loss angle (dielectric tangent) (tanδ) ranges are based on Figure 2 (quoted from "Microwave Oven and Microwave Use Handbook" edited by Atsuko Higo, Japan Industrial Newspaper, 1987, p. 16), and are considered to be the ranges that are practically difficult to microwave-heat, that is, the loss factor (ε r tan δ) is calculated. In other words, the resistance to microwave heating is determined within a range where the loss factor is small. The desirable range is for tan δ to be 0.02 or less, preferably 0.002 or less, and even more preferably 0.0002 or less.

[0017] The above-mentioned configuration can solve the above-mentioned problem (demand for further high purity of the processed product (particularly, reduction of the allowable content of metal contaminants)).

[0018] When the dielectric layer is made of a polymeric material, even if polymeric wear particles are mixed in, they can be eliminated by heating, volatilizing, and incinerating the polymeric wear particles contained in the product, as in the vibration treatment method of the present invention. The polymeric material may be resin or rubber as long as it satisfies the above-mentioned properties, or may be inorganic polymer or reinforced resin (FRP, etc.) as long as it satisfies the above-mentioned dielectric properties.

[0019] Although the resin may be polyamide or the like, a thermoplastic resin that is relatively resistant to heat generation by microwaves, i.e., a low-polarity thermoplastic resin, is preferable. Examples of such thermoplastic resins include crystalline polypropylene (crystalline PP), high-density polyethylene (high-density PE), and polytetrafluoroethylene (PTFE). Of these, crystalline PP is preferable because it has superior mechanical properties compared to high-density PE and superior flammability compared to PTFE.

[0020] When the dielectric layer is made of a ceramic material, it is possible to use a material with a much higher hardness than metals (for example, alumina: 15-18Hv, while SUS304: 2Hv). This significantly reduces the generation of wear particles at the raw material contact area (powder contact area). Note that ceramic materials include not only inorganic oxides such as alumina and zirconia, but also nitrides, carbides, borides, or composite compounds containing these.

[0021] In the above configuration, the thickness of the dielectric layer varies slightly depending on the constituent material, but is usually 0.5 to 5 mm, preferably 0.5 to 2.5 mm. If the thickness is too thin, it will wear out quickly, its service life will be short, and maintenance will be difficult. On the other hand, if the thickness is too thick, it will be excessive in quality and will increase in weight or reduce the processing volume, which is undesirable.

[0022] In the vibration treatment device having the above configuration, it is desirable that the dielectric layer be configured as a cartridge container that can be attached to and detached from the treatment container body. This makes it easy to input raw materials and remove products, and if the cartridge container is a disposable type made of thermoplastic resin such as PP, it becomes possible to simultaneously heat and volatilize the organic polymer wear powder and incinerate the cartridge container.

[0023] The vibration treatment device configured as described above does not usually require a temperature-controlled jacket, and can even be used for atmospheric pressure or low vacuum treatment. The temperature-controlled jacket is not necessary because microwave heating allows selective heating based on differences in loss factors. If the loss factor of the raw material (powder) is small, only the droplets (water droplets) adhering to the powder, which have an extremely large loss factor, can generate heat during vibration treatment, efficiently drying the raw material. Furthermore, there is no need to create a high vacuum inside the treatment vessel to promote evaporation. Therefore, there is no need for a temperature control mechanism such as a temperature-controlled jacket, a suction means for creating a high vacuum, or a high-level seal for the treatment vessel. As a result, the additional costs associated with microwave heating can be reduced.

[0024] In addition, the present invention employs various configurations in which the powder-contacting portion of the processing vessel in the vibration processing device (vibration drying device) in the conventional and prior applications is not made of a dielectric layer, and of course exhibits the effects of these configurations (see the specifications of the prior application

[0012] to

[0018] ).

[0025] [Brief explanation of the drawings]

[0026] [Figure 1] 1 is a longitudinal cross-sectional view (part of the cross-sectional view is omitted) of an example of a vertical vibration dryer according to the present invention in an assembled state. [Figure 2] FIG. 1 is a diagram showing the dual dielectric characteristics of the relative permittivity (εr) and the dielectric loss tangent (tanδ) of various materials, which are used as the selection criteria for the dielectric layer constituent materials in the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0027] An embodiment in which the present invention is applied to a vertical vibration dryer will be described below with reference to Figure 1. The present invention is not limited to this embodiment, but can be applied to various aspects within the technical scope of the claims, and can also be applied to horizontal vibration dryers and vibration fluidized beds. Note that the reference numerals in the illustration are basically the same as those in Figure 1 of the prior application.

[0028] In this embodiment, a microwave oscillator M is basically attached to a vertical vibration dryer VU. The vibration dryer VU includes a cylindrical vertical treatment container 11 and an oscillator (vibration means) 13 that vibrates the treatment container 11.

[0029] Specifically, the processing vessel 11 is supported by a compression coil spring (elastic body) 18 disposed on the stand 17. Here, the compression coil spring 18 may be a leaf spring or an elastic body such as vibration-isolating rubber depending on the output and type of the vibration motor 13.

[0030] In the illustrated example, the processing vessel 15 has a central raised portion (navel) at the bottom, providing an annular processing space T, allowing the raw material held in the annular processing space to swirl, and the microwave irradiation port is located in a portion of the annular processing space. The central raised portion is supported by a valve body 29 of a vertically movable valve V for product discharge. A product discharge pipe 31 is attached to the valve body downstream of the valve body 29. The vertically movable valve body 30 is driven by an air cylinder 30a. In addition to a microwave irradiation section (irradiation port) R (described below), the ceiling wall of the processing vessel 15 is equipped with a dust collection section D on the upper surface of the ceiling, which includes a raw material inlet (not shown), a built-in filter 33, and a steam exhaust port 35. A punched plate 31 is attached to the entrance of the dust collection section D to prevent microwave leakage. Further, in the dust collecting section D, although not shown, a suction pipe is connected to the steam exhaust port 35, and the steam exhaust pipe is connected to a suction pump via a steam recovery container or the like.

[0031] In the above configuration, in this embodiment, microwaves emitted from the microwave oscillator M are connected to the microwave irradiation unit R of the processing vessel 11, which is an applicator, via a microwave coaxial cable 37, which is a flexible waveguide member. The microwave irradiation unit R is made up of a vacuum seal unit 43 connected to the tip side of the coaxial cable 3737 and an irradiation antenna 45 that outputs microwaves. Although microwave attenuation is greater than that of a waveguide, the coaxial cable 37 is more flexible and has better vibration resistance than a waveguide.

[0032] Although some components of the microwave oscillator M are not shown, the oscillator (magnetron) is connected to a power supply control panel E, and a control mechanism such as an isolator is connected to the outlet side of the oscillator via an apparatus waveguide 39. A mode converter 41 is provided at the outlet of the waveguide 39. The mode converter 41 can alternately switch between a coaxial cable mode and a waveguide mode. The base side of the coaxial cable 37 is connected to the converter 41.

[0033] The tip of the coaxial cable 37 is a microwave irradiation section R that is composed of a seal section 47 and an antenna section 48 .

[0034] Up to this point, the embodiment is substantially the same as the embodiment in the prior application. In the embodiment according to the present invention, at least the portion of the inner surface that comes into contact with the raw material during operation is made of a dielectric layer 15. In the illustrated example, the dielectric layer 15 is formed over the entire height of the inner wall and the entire bottom surface except for the discharge valve 29. Here, the raw material contact portion of the valve body V may also be covered with a dielectric layer, but if the valve body 29 is made of a ceramic material, the generation of metal wear powder can be prevented.

[0035] As described above, the material for forming the dielectric layer 15 has a relative dielectric constant (ε rIn the illustrated example, the dielectric layer 15 is a resin layer, and is preferably a flammable non-polar thermoplastic resin (e.g., PP), as described above. The dielectric layer may be formed of a cartridge container that is detachable from the processing container body. This provides the above-described functions and effects.

[0036] In the above, the processing vessel body is usually made of steel from the viewpoint of strength, so no special electromagnetic shielding is required except for the underside of the valve body. If the valve body is made of a ceramic material, a punching plate is attached to the underside. The valve body may be made of metal, and its upper and peripheral surfaces may be formed with a dielectric layer. Furthermore, as long as strength can be ensured, the processing vessel body may be made of a metal punching plate for electromagnetic wave shielding.

[0037] The use of the vertical vibration dryer is basically the same as that of the conventional or prior application (see the specification of the prior application

[0029] to

[0038] If the raw material contains inorganic powder and the dielectric layer is made of a polymer material such as thermoplastic resin, there is a risk that polymer abrasion powder will be included in the product after vibration treatment, but since inorganic powder is usually sintered when made into a molded product, the polymer abrasion powder will be burned away and will not be a problem. [Explanation of symbols]

[0038] 11 Processing container (main body) 13 Vibration motor (vibration means) 15 Dielectric Layer 21 Central protuberance (umbilicus) 35 Steam exhaust port 37 Coaxial cable (flexible waveguide member) 39 Oscillator (Magnetron) UV vertical vibration dryer D Dust collection section M Microwave Oscillator E power supply T Annular processing space R Microwave irradiation section V valve body

Claims

1. A vibration treatment device equipped with a vibration means for vibrating a treatment container, A vibration treatment device in which the raw material is a powder or a powder-containing raw material in a slurry or paste form, and the vibration means causes the raw material charged into the treatment vessel to flow upward and downward along the wall of the treatment vessel, A microwave oscillator is provided, and an output port of the microwave oscillator is connected to the microwave irradiation unit via a coaxial cable; the treatment vessel is provided with a steam exhaust means and has an electromagnetic shielding structure, and further, at least the raw material contact portion of the inner surface during operation is made of a dielectric layer made of a polymer material and having a thickness of 0.5 to 5 mm; The polymer material is a polymer material that satisfies both of the following characteristics: a relative dielectric constant (εr) of 10 or less and a loss angle (tanδ) of 0.08 or less (both at a frequency of 2.45 GHz and at 25°C; the same applies hereinafter). A vibration treatment device characterized by:

2. 2. The vibration treatment apparatus according to claim 1, wherein the treatment vessel further comprises a temperature control jacket.

3. 2. The vibration treatment apparatus according to claim 1, wherein the dielectric layer is formed in a cartridge container that is detachable from the treatment container body.

4. The vibration treatment device according to claim 1, characterized in that the vibration treatment device is a vertical vibration dryer, the treatment container has a central raised portion (navel portion) at the bottom and is provided with an annular treatment space, the raw material held in the annular treatment space is capable of swirling and flowing, and the microwave irradiation section is provided for a part of the annular treatment space.

5. 5. The vibration treatment device according to claim 4, wherein the central raised portion is formed as a vertical valve for opening and closing a product discharge port formed in the center of the bottom of the treatment vessel.

6. A vibration treatment method, characterized in that combustible polymer abrasion powder contained in a product prepared using the vibration treatment device according to claim 1 is burned away.

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