JP2004087224A - Drying device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a drying device which can cleanly dry earth and sand containing ores or the like in a favorable state by utilizing high frequency induction heating. <P>SOLUTION: The drying device comprises a high frequency power source (high frequency power source 3), a high frequency induction heating coil 7 to which high frequency power is supplied from the high frequency power source, a container 5 for filling a substance to be dried (for example, zeolite) arranged at a position surrounded by the high frequency induction heating coil 7, and a magnetic bodies (metal plate 6) arranged in the container 5. The substance to be dried, filled in the container 5 and directly contacting with the magnetic body is heated and dried by making a high frequency current flow through the high frequency induction heating coil 7 and heating the magnetic substance by high frequency induction. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a drying device, and more particularly to a drying device suitable for drying earth and sand including ore and the like.
[0002]
[Prior art]
Conventionally, when drying natural ore or the like, high-temperature dry air heated by a gas burner is used. For example, in order to use natural zeolite in an oxygen generator that removes nitrogen from the atmosphere, it is necessary to evaporate the water content of natural zeolite. For this reason, conventionally, a heated drying chamber (container) filled with natural zeolite is used. By sending air, the natural zeolite is heated to evaporate (dry) the moisture. On the other hand, dielectric heating is used for drying wood and the like.
[0003]
[Problems to be solved by the invention]
However, the heating method using high-temperature dry air heated by a gas burner requires a large-scale closed chamber (container), and further has problems such as a poor working environment.
[0004]
On the other hand, it is conceivable to heat the natural ore by using dielectric heating. In this case, the temperature is increased by sandwiching the natural ore with an electrode or the like. However, when heating natural ore with such a dielectric heating method, compared with wood or the like, a large-scale facility is required for processing a required amount of ore, and the heating time is long. In addition, problems such as leakage of electromagnetic waves occur.
[0005]
SUMMARY OF THE INVENTION The present invention has been made in view of the above situation, and has as its object to use a high-frequency induction heating so as to desirably and cleanly dry earth and sand including ore and the like. Is to provide.
[0006]
[Means to solve the problem]
In order to achieve the above object, in the present invention, a high-frequency power supply, a high-frequency induction heating coil to which high-frequency power is supplied from the high-frequency power supply, and an object to be dried disposed at a position surrounded by the high-frequency induction heating coil A container for filling, and a magnetic body disposed inside the container, respectively, and a high-frequency current is applied to the high-frequency induction heating coil to perform high-frequency induction heating of the magnetic body, thereby filling the container. The object to be dried that is in direct contact with the magnetic body is dried by heating.
In the present invention, the magnetic body is a heating conductor formed of a magnetic plate, a magnetic round bar, or a magnetic polygonal square bar.
In the present invention, the object to be dried is earth and sand containing ore and the like.
Further, in the present invention, the container is made of a nonmagnetic metal, ceramic, an insulating material having high heat resistance, a resin material or an inorganic material having high heat resistance.
In the present invention, the container is made of a non-magnetic metal, and the magnetic body disposed in the container is made of a metal having magnetic properties.
In the present invention, the magnetic body is made of an alloy.
In the present invention, the alloy is an alloy containing iron as a main component or stainless steel.
In the present invention, the Curie point (Curie temperature) of the magnetic material is appropriately selected by adjusting the components of the alloy, and the property that the high-frequency induction heating temperature of the magnetic material does not exceed the Curie point is used. The heating temperature of the object to be heated is set appropriately.
Further, in the present invention, the impedance of the high-frequency induction heating coil viewed from the high-frequency power supply unit side is controlled to be constant so as to be an impedance corresponding to the Curie point of the magnetic substance, thereby keeping the magnetic substance constant. High frequency induction heating to temperature.
[0007]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to FIGS.
[0008]
1 and 2 schematically show the configuration of a drying apparatus 1 according to one embodiment of the present invention. The drying apparatus 1 according to the present embodiment is an apparatus used for drying zeolite, and as shown in FIG. 1, a high-frequency induction heating section 2 for heating an object to be heated (natural zeolite), and a high-frequency induction heating section. It comprises a high-frequency power supply section 3 composed of an oscillator for supplying a high-frequency current to the section 2, and a matching section 4 provided between the high-frequency induction heating section 2 and the high-frequency power supply section 3.
[0009]
As shown in FIGS. 1 to 3, the high-frequency induction heating unit 2 includes a container 5 made of a zeolite-filled pipe made of a non-magnetic metal such as stainless steel or ceramic, for example. A plurality of magnetic metal plates (ordered packing made of an electromagnetic derivative; a magnetic plate as a magnetic material) 6 and a container 5 which are regularly arranged in the interior (hollow portion) at regular intervals so as to be substantially parallel to each other and opposed to each other, A high-frequency induction heating coil 7 disposed coaxially around the outer periphery of the container 5 so as to surround the container. For example, as shown in FIG. 3, the container 5 is detachably attached to both ends of the container main body 5a so as to close a cylindrical container main body 5a and a pair of upper and lower openings of the container main body 5a. It is composed of a pair of lids 5b and 5c to be mounted, and a closed container is constituted by the container body 5a and the lids 5b and 5c.
[0010]
As shown in FIG. 2, the high-frequency power supply 3 is a voltage-type inverter circuit including a DC power supply E, a coil L ₀ , a capacitor C ₀ , diodes D _{1 to} D ₄ , and switches S _{1 to} S _4. It is configured. Note that the high-frequency power supply 3 may be configured by a current-type inverter circuit instead of a voltage-type inverter circuit. On the other hand, the above-mentioned matching section 4 is configured by a capacitor C. Then, a high-frequency current of a required frequency is supplied from the high-frequency power supply unit 3 to the high-frequency induction heating coil 7 via the matching unit 4.
[0011]
Next, the procedure for drying zeolite using the drying apparatus 1 having the above-described configuration will be described below. First, an aggregate of granular zeolites (each particle has a diameter of, for example, about 2 to 3 mm) is put into the container 5 through an opening of the main body 5a to fill the container, and then lids are provided at both ends of the container 5. 5b and 5c are attached, and the zeolite is filled in the closed container 5. As a result, the zeolite is brought into a state where the zeolite is in direct contact with the front and back surfaces of each metal plate 6 in the container 5.
[0012]
Thereafter, a high-frequency current of a required frequency is supplied from the high-frequency power supply unit 3 to the high-frequency induction heating coil 7 via the matching unit 4. Accordingly, a high-frequency current flows through the high-frequency induction heating coil 7 to generate a magnetic flux Φ crossing the plurality of metal plates 6 as indicated by arrows and broken lines in FIG. ) Is induced, and the plurality of metal plates 6 are Joule-heated by the eddy current. Then, the granular zeolite in contact with the plurality of metal plates 6 thus heated by the high-frequency induction heating is rapidly heated and dried by the heat conduction from the metal plates 6. The dried zeolite is removed from the container body 5a by removing the lids 5b and 5c, and thereafter, the same operation as described above is repeated for another zeolite to be dried.
[0013]
Although the oscillation frequency of the power supply of the high-frequency power supply unit 3 depends on the size of the container 5, a relatively low frequency (e.g., for example, for induction heating the magnetic metal plate 6 disposed inside the container 5). (Approximately 0.5 kHz). On the other hand, the temperature control of the zeolite, which is a filling material, is performed by embedding a temperature sensor (for example, a thermocouple) in the zeolite filled in the container 5 and measuring the temperature to output the output from the high-frequency power supply unit 3. What is necessary is just to change it suitably.
[0014]
Further, a heating temperature control method utilizing the characteristic of the Curie point of the magnetic metal plate 6 installed inside the container 5 may be adopted. This control method utilizes the property that the maximum temperature of heating is determined by the Curie point of the metal plate 6 to be heated when the metal plate 6 is heated. From such a property, when setting the heating temperature of the object to be heated such as zeolite, it is possible to realize a heating temperature having a Curie point corresponding to the object to be heated by using an alloy for the metal plate 6. Here, the principle of the temperature control will be described as follows. That is, the electrical conditions in the high-frequency induction heating equipment greatly change with the Curie point as a boundary. In particular, the impedance (resistance value) seen from the high-frequency induction heating equipment side greatly differs before and after exceeding the Curie point. Therefore, if the impedance (resistance value) is controlled so as to be always kept constant, the temperature of the magnetic metal plate 6 installed inside the container 5 can be controlled so as to always keep the temperature near the Curie point.
[0015]
The Curie point of iron is a temperature at which the crystal structure of zeolite is broken, and the Curie point of nickel is slightly lower than the good drying temperature of zeolite. Therefore, it is preferable that the metal plate 6 be made of iron or nickel. Absent. Therefore, in the present embodiment, an alloy containing iron as a main component, stainless steel (Fe—Cr—Ni) is used.
[0016]
When the zeolite is dried using the drying apparatus 1 having the above-described configuration, the filler such as zeolite packed in a container 5 made of a pipe material or the like is supplied from the high-frequency induction heating coil (work coil) 7. The non-contact power supply by electromagnetic induction heats the plurality of metal plates 6 in the container 5 by high frequency induction (heat is generated by Joule heat generated by eddy current), and the filler (for example, zeolite) in the container 5 is electromagnetically heated. Drying is performed by rapid heating by directly contacting the metal plate 6 as a derivative, so that clean and good drying can be performed without using a temperature sensor. Furthermore, the Curie point of the metal plate 6 is appropriately selected by adjusting the composition of the alloy of the material of the metal plate 6 so that the heating temperature of the metal plate 6 and thus the zeolite to be heated can be adjusted by the high-frequency induction heating coil. The temperature can be always set to a good temperature without breaking the crystal structure of the zeolite without controlling the power applied to 7. Thus, according to the drying apparatus 1 of the present embodiment, zeolite can be dried with high temperature accuracy and in a good and clean environment without using a temperature sensor. In addition, according to the drying apparatus 1 of the present embodiment, even when the high-frequency induction heating is temporarily stopped during the drying process of the earth and sand including the ore or the like, the reheating can be easily performed.
[0017]
As mentioned above, although one embodiment of the present invention was described, the present invention is not limited to this embodiment, and various modifications and changes are possible based on the technical idea of the present invention. For example, in the above-described embodiment, the drying apparatus 1 for drying zeolite has been described. However, the present invention is applicable not only to zeolite but also to apparatuses for drying various ores, earth and sand, and the like. Further, the shape and structure of the container 5 can be changed as needed.
[0018]
Further, in the above-described embodiment, the magnetic plate made of the metal plate 6 is arranged as the heating conductor inside the container 5, but instead, it is made of a magnetic round bar or a magnetic polygonal square bar. A heating conductor (magnetic material) may be provided. In the above-described embodiment, the container 5 made of non-magnetic metal such as stainless steel or ceramic is used. However, instead of this, a non-magnetic insulating material having high heat resistance, a resin material, or an inorganic material is used. May be used.
[0019]
【The invention's effect】
The present invention according to claim 1 includes a high-frequency power supply, a high-frequency induction heating coil to which high-frequency power is supplied from the high-frequency power supply, and a container for filling the object to be dried, which is disposed at a position surrounded by the high-frequency induction heating coil. And a magnetic body disposed inside the container, and a high-frequency current is applied to the high-frequency induction heating coil to heat the magnetic body by high-frequency induction, thereby filling the container and directly contacting the magnetic body. Since the object to be dried is dried by heating, the object to be dried is dried using high-frequency induction heating, so that clean and good drying can be easily performed with simple equipment.
[0020]
According to the present invention described in claim 2, the magnetic body is a heating conductor formed of a magnetic plate or a magnetic round bar or a magnetic polygonal square bar. By selecting a magnetic material for heating in accordance with the shape, size, material, or the like, it is possible to perform optimal drying on an object to be dried.
[0021]
According to the third aspect of the present invention, the object to be dried is earth and sand containing ore and the like. The drying process can be performed efficiently and smoothly. According to the present invention, it is possible to provide a drying apparatus which is particularly suitable for drying ores, particularly natural ores such as zeolite, and which is suitable and very practical.
[0022]
According to a fourth aspect of the present invention, since the container is made of a nonmagnetic metal, ceramic, an insulating material having high heat resistance, or a resin or inorganic material having high heat resistance, a high-frequency induction heating coil is provided. The magnetic flux generated from the magnetic material can be effectively applied to the magnetic material through the container. Therefore, the material to be dried (for example, a natural ore such as zeolite) that is in direct contact with the magnetic material can be efficiently heated. be able to.
[0023]
Further, according to the present invention, the container is made of a non-magnetic metal, and the magnetic body disposed in the container is made of a metal having magnetic properties. Since both are made of metal, the manufacturing of the drying apparatus can be performed easily and inexpensively, and the durability can be improved.
[0024]
In the present invention described in claim 6, since the magnetic material is made of an alloy, the type of the component and the composition ratio are appropriately adjusted according to the type of the material to be dried. It is possible to set the heating temperature suitable for the drying treatment of the dried product.
[0025]
Further, in the present invention according to claim 7, since the alloy is an alloy containing iron as a main component or stainless steel, especially when zeolite is to be dried, the crystal structure of zeolite is changed. It can be dried at a heating temperature that does not cause breakage.
[0026]
Further, according to the present invention, the Curie point (Curie temperature) of the magnetic material is appropriately selected by adjusting the components of the alloy, and the high-frequency induction heating temperature of the magnetic material does not become higher than the Curie point. Since the heating temperature of the object to be heated is appropriately set by utilizing this, the heating temperature of the object to be dried can always be kept constant without using a temperature sensor or the like. According to the conventional drying method, it is difficult to control the temperature of the dry air. However, according to the present invention, it is possible to realize a simple drying method in which the temperature is controlled by focusing on the Curie point of the metal plate.
[0027]
Further, according to the present invention, the impedance of the high-frequency induction heating coil as viewed from the high-frequency power supply unit is controlled to be constant so as to be an impedance corresponding to the Curie point of the magnetic material. Is subjected to high-frequency induction heating to a constant temperature, so that it is not necessary to provide feedback control means for the power supplied to the high-frequency induction heating coil, and drying at a constant heating temperature is always possible.
[Brief description of the drawings]
FIG. 1 is a block diagram illustrating a configuration of a drying device according to an embodiment of the present invention.
FIG. 2 is a configuration diagram showing the configuration of the drying apparatus of FIG. 1 in further detail.
FIG. 3 is a perspective view illustrating a configuration of a heating unit of the drying device in FIG. 1;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Drying device 2 Heating part 3 High frequency power supply part 4 Matching part 5 Container 5a Container main body 5b, 5c Lid 6 Metal plate (magnetic plate)
7 High frequency induction heating coil

Claims (9)

A high-frequency power source, a high-frequency induction heating coil to which high-frequency power is supplied from the high-frequency power source, a container for filling the object to be dried disposed at a position surrounded by the high-frequency induction heating coil, and disposed inside the container. A magnetic substance, and a high-frequency current is passed through the high-frequency induction heating coil to perform high-frequency induction heating on the magnetic substance, so that the object to be dried filled in the container and in direct contact with the magnetic substance is provided. A drying device characterized by heating and drying. The drying device according to claim 1, wherein the magnetic material is a heating conductor formed of a magnetic plate, a magnetic round bar, or a magnetic polygonal square bar. The drying device according to claim 1, wherein the object to be dried is earth and sand including ore and the like. 4. The drying device according to claim 1, wherein the container is made of a nonmagnetic metal, ceramic, an insulating material having high heat resistance, or a resin material or an inorganic material having high heat resistance. . The drying device according to any one of claims 1 to 4, wherein the container is made of a non-magnetic metal, and the magnetic body disposed in the container is made of a metal having magnetic properties. apparatus. The drying device according to any one of claims 1 to 5, wherein the magnetic material is made of an alloy. The drying device according to claim 6, wherein the alloy is an alloy containing iron as a main component or stainless steel. The Curie point of the magnetic body is appropriately selected by adjusting the components of the alloy, and the heating temperature of the object to be heated is adjusted appropriately by utilizing the property that the high-frequency induction heating temperature of the magnetic body does not exceed the Curie point. The drying device according to claim 6, wherein the drying device is set to: By controlling the impedance of the high-frequency induction heating coil as viewed from the high-frequency power supply unit to be constant so as to be an impedance corresponding to the Curie point of the magnetic substance, the magnetic substance is subjected to high-frequency induction heating to a constant temperature. The drying device according to any one of claims 1 to 8, wherein the drying device is configured as described above.

Images