JP6927510B2 - Heating and stirring device - Google Patents

Description

The present invention relates to a heating and stirring device for heating and stirring an object to be processed contained in a container.

In recent years, practical application of a technique for recovering biogas containing methane gas as a main component from sewage sludge generated in large quantities in sewage treatment plants and wastewater treatment plants has been promoted. As a method for recovering biogas from sewage sludge, there is a methane fermentation treatment technique capable of recovering methane gas at the same time as reducing the volume and weight of sludge (see, for example, International Publication No. 2012/132799 (Patent Document 1)). ). In this methane fermentation treatment technique, a heating and stirring device for heating the sewage sludge put into the methane fermentation tank while stirring is generally used.

Conventionally, in a heating and stirring device, a configuration is known in which a heating means such as a resistance heater is arranged outside a container in which an object to be processed is housed, and the container is heated by using the heating means to heat the object to be processed. (See, for example, Utility Model Registration No. 3012756 (Patent Document 2)). Some conventional heating and stirring devices use steam, hot water, oil, or the like as a heat source in addition to the heating means such as a resistance heater.

International Publication No. 2012/132799 Utility model registration No. 3012756

Shimada et al., "Temperature uniformity and heat transfer characteristics in simultaneous operation of heating and stirring water candy with induction heating and stirring blades", Society of Chemical Engineers of Japan, 81st Annual Meeting (2016)

However, in the configuration in which the heating means is arranged outside the container described in Patent Document 2, when the viscosity of the object to be processed becomes high, it becomes difficult to stir the object to be processed, and as a result, the temperature of the object to be processed varies. There is a problem of growing up.

As a result of intensive research to solve the above problems, the inventors of the present application have found that the temperature variation in a highly viscous object to be processed can be reduced by electromagnetically inducing heating the stirring blade (for example, Shimada et al., Et al. "Temperature uniformity and heat transfer characteristics in simultaneous operation of heating and stirring water candy with an induction heating and stirring blade", Chemical Engineering Society, 81st Annual Meeting (2016) (Non-Patent Document 1)).

On the other hand, in order to electromagnetically induce and heat the stirring blade, it is necessary to arrange the electromagnetic induction coil outside the container, so that there is a limit to the miniaturization of the physique of the heating and stirring device. Further, in order to sufficiently interlink the alternating magnetic field generated by the electromagnetic induction coil with the stirring blade in the container, the container must be formed of a non-conductor, and the shape and size of the container are restricted. Further, in response to the demand for power saving of the heating and stirring device, improvement of heating efficiency has also been required.

The present invention has been made to solve such a problem, and an object of the present invention is to provide a heating and stirring device capable of realizing miniaturization of the device and high heating efficiency.

According to the present invention, the heating and stirring device for heating and stirring the object to be processed contained in the container includes a stirring blade, an energizing unit, and a feeding unit. The stirring blade is rotatably arranged in the container, and the first conductor portion is formed at least in a part thereof. The energizing portion has a second conductor portion and an insulator that covers the outer periphery of the second conductor portion. The power feeding unit is arranged outside the container and supplies a high frequency current to the energizing unit. In the container, at least a part of the energizing part is arranged in the vicinity of the stirring blade.

According to the present invention, since the energizing portion of the high-frequency current is arranged in the vicinity of the stirring blade in the container, the stirring blade generates Joule heat by the electromagnetic induction action of the alternating magnetic field generated by the energizing portion and energizes. It is heated by receiving the Joule heat generated in the part. This eliminates the need for an electromagnetic induction coil outside the container, so that the heating and stirring device can be miniaturized. Further, since high heating efficiency is realized, it is possible to contribute to power saving of the heating and stirring device.

It is a figure which showed schematic the structure of the heating stirring apparatus which concerns on embodiment of this invention. FIG. 1 is a cross-sectional view taken along the line II-II of FIG. It is a figure explaining another structural example of a current-carrying part. It is a figure explaining the electric circuit structure of the heating agitator which concerns on this embodiment. It is a figure which showed schematic structure of the heating and stirring device of the external heating type (FIG. 5A) and the heating and stirring device of the internal heating type (FIG. 5B). It is a figure which shows the relationship between the stirring Reynolds number and the maximum variation temperature for each of the heating stirrer of an external heating type and the heating stirrer of an internal heating type. It is a figure which shows the relationship between the stirring Reynolds number and the thermal conductance for each of the heating stirrer of an external heating type and the heating stirrer of an internal heating type. It is a figure for demonstrating the difference between two kinds of internal heating type heating and stirring apparatus. It is a figure which showed schematicly the heat transfer path in an internal energization type heating agitator. It is a figure explaining the structural example of the stirring blade and the energizing part applied to the heating stirring apparatus which concerns on this embodiment. It is a figure explaining the structural example of the stirring blade and the energizing part applied to the heating stirring apparatus which concerns on this embodiment. It is a figure explaining the structural example of the stirring blade and the energizing part applied to the heating stirring apparatus which concerns on this embodiment. It is a figure explaining the structural example of the stirring blade and the energizing part applied to the heating stirring apparatus which concerns on this embodiment. It is a figure explaining the structural example of the stirring blade and the energizing part applied to the heating stirring apparatus which concerns on this embodiment. It is a figure explaining the structural example of the stirring blade and the energizing part applied to the heating stirring apparatus which concerns on this embodiment. It is a figure explaining the structural example of the stirring blade and the energizing part applied to the heating stirring apparatus which concerns on this embodiment. It is a figure which showed roughly the structure of the modification example of the heating stirring apparatus which concerns on this embodiment.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The same or corresponding parts in the drawings are designated by the same reference numerals, and the description thereof will not be repeated.

[Structure of heating and stirring device]
The heating and stirring device 100 according to the embodiment of the present invention is a device for heating and stirring the object to be processed 20 housed inside the container 13. The heating and stirring device 100 can be applied to, for example, a sludge treatment device that recovers biogas from sewage sludge.

First, the configuration of the heating / stirring device 100 according to the present embodiment will be described with reference to FIG. Note that FIG. 1 shows a cross-sectional structure of the heating and stirring device 100 along the axial direction AX.

With reference to FIG. 1, the heating and stirring device 100 includes a stirring blade 1, a rotating shaft 2, sealing members 3, 15 and a feeding portion 4, conductive wires 9a and 9b, an energizing portion 10, and a container 13. And a lid portion 14.

FIG. 1 shows a state in which the object to be processed 20 is housed inside the container 13. A lid portion 14 is attached to the container 13. The container 13 and the lid portion 14 are made of, for example, resin. The container 13 and the lid portion 14 may be composed of either a conductor or a non-conductor.

The object to be treated 20 is, for example, sewage sludge. However, the object to be treated 20 is not limited to sewage sludge, and can be applied to any of gas, liquid, solid (powder, granule, etc.) and a mixture thereof.

The stirring blade 1 is arranged inside the container 13, and a part thereof is immersed in the object 20 to be processed. The stirring blade 1 is, for example, an anchor blade. As will be described later, as the stirring blade 1, a stirring blade having an appropriate shape depending on the viscosity of the object to be processed 20 can be used.

A conductor portion (first conductor portion) is formed in at least a part of the stirring blade 1. At least a part of the stirring blade 1 is typically made of metal. At least a part thereof is made of, for example, stainless steel (SUS304).

Specifically, the stirring blade 1 can adopt a structure in which a part thereof is made of a conductor and the other part is made of a non-conductor. Alternatively, a structure in which the entire stirring blade 1 is formed of a conductor can be adopted. For example, when the stirring blade 1 is composed of a shaft portion and a blade portion, as the former structure, the blade portion (or a part thereof) is formed of a conductor, and the remaining portion including the shaft portion is a non-conductor. Can be formed with. On the other hand, as the latter structure, both the shaft portion and the blade portion can be formed of a conductor. In the following description, the stirring blade 1 which is entirely made of a conductor will be illustrated.

One end of the rotating shaft 2 in the axial direction AX is connected to the main shaft 1a of the stirring blade 1 inside the container 13. The rotating shaft 2 is made of, for example, stainless steel (SUS304). The sealing member 3 is arranged between one end of the rotating shaft 2 and the main shaft 1a. The sealing member 3 is configured to be able to seal the gap between one end of the rotating shaft 2 and the main shaft 1a. For the sealing member 3, for example, an insulating O-ring can be used.

The rotating shaft 2 is inserted into a through hole 14a formed in the lid portion 14. A sealing member 15 is arranged between the rotating shaft 2 and the through hole 14a. The sealing member 15 is configured to be able to seal the gap between the rotating shaft 2 and the through hole 14a. The sealing member 15 is, for example, a mechanical seal. In this case, the gap between the rotating shaft 2 and the through hole 14a is sealed by the sealing member 15 by inserting the rotating shaft 2 into the through hole 14a with the mechanical seal wound around the outer peripheral surface of the rotating shaft 2. Can be done.

Outside the container 13, the other end of the rotating shaft 2 in the axial direction AX is connected to a rotating shaft of a motor (not shown). The stirring blade 1 is rotated by rotationally driving the rotating shaft 2 by the motor. As a result, the object to be processed 20 is agitated.

The power feeding unit 4 is arranged outside the container 13 and is configured to supply a high frequency current to the energizing unit 10. Specifically, the power feeding unit 4 includes an AC power supply 5, a high frequency transformer 6, a power transmission coil 7, a power receiving coil 8, and conductive wires 9a and 9b.

The AC power supply 5 is, for example, a commercial power supply. The high-frequency transformer 6 receives power from the AC power source 5 to generate high-frequency AC power.

When the power transmission coil 7 receives high-frequency AC power from the high-frequency transformer 6, the power transmission coil 7 transmits power to the power reception coil 8 in a non-contact manner through an electromagnetic field generated around the power transmission coil 7. That is, the power transmission coil 7 and the power reception coil 8 realize non-contact power supply that transmits electric power in a non-contact manner. As shown in FIG. 1, the power transmission coil 7 is arranged so as to surround the outer circumference of the rotating shaft 2. The power transmission coil 7 can remain stationary with respect to the rotation of the rotating shaft 2.

The power receiving coil 8 receives high-frequency power output from the power transmission coil 7 in a non-contact manner. As shown in FIG. 1, the power receiving coil 8 is arranged so as to surround the outer circumference of the rotating shaft 2. The power receiving coil 8 is configured to rotate integrally with the rotating shaft 2.

A conductive wire 9a is electrically connected to one end of the power receiving coil 8. A conductive wire 9b is electrically connected to the other end of the power receiving coil 8. The conductive wires 9a and 9b extend into the container 13 through the space formed inside the rotating shaft 2.

The energizing unit 10 is arranged inside the container 13. Inside the container 13, the conductive wire 9a is electrically connected to one end of the energizing portion 10. The conductive wire 9b is electrically connected to the other end of the energizing portion 10. As a result, a path is formed in which a high-frequency current is supplied from the power receiving coil 8 to the energized portion 10 through the conductive wires 9a and 9b.

The energizing unit 10 is in contact with the stirring blade 1. In the example of FIG. 1, the energizing unit 10 is in contact with the blade portion of the stirring blade 1. FIG. 2 is a cross-sectional view taken along the line II-II of FIG. With reference to FIG. 2, the energizing portion 10 has a conductor portion 11 (second conductor portion) and an insulator 12 that covers the outer periphery of the conductor portion 11. The conductor portion 11 is typically made of metal. The conductor portion 11 is formed of, for example, an aluminum (Al) plate having a thickness of about several mm. The insulator 12 is made of, for example, a metal oxide. When the conductor portion 11 is an aluminum plate, the insulator 12 can be formed _{of alumina (Al 2} O _3).

The energizing portion 10 is joined to the stirring blade 1 by using, for example, an adhesive. As a result, the energizing portion 10 can be brought into contact with the stirring blade 1 while maintaining electrical insulation. If the electrical insulation between the energizing unit 10 and the stirring blade 1 is ensured, for example, as shown in FIG. 3, the energizing unit 10 becomes the stirring blade 1 with the insulating body 12 covered by the stirring blade 1. You may make contact.

As another form in which the energizing unit 10 is brought into contact with the stirring blade 1, the energizing unit 10 may be screwed to the stirring blade 1. Alternatively, the energizing portion 10 may be simply superposed on the stirring blade 1 without using a fixing member such as an adhesive or a screw.

In the heating and stirring device 100 according to the present embodiment, the energizing unit 10 is arranged inside the container 13 in the vicinity of the stirring blade 1. “Placed in the vicinity of the stirring blade 1” means that the distance between the stirring blade 1 and the energizing portion 10 is equal to or less than the threshold value. As shown in FIG. 1, the configuration in which the energizing unit 10 is in contact with the stirring blade 1 is applicable because the distance between the stirring blade 1 and the energizing unit 10 is substantially 0. On the other hand, in contrast to the configuration of FIG. 1, even if the surfaces of the stirring blade 1 and the energizing portion 10 are separated from each other, this applies if the distance is equal to or less than the threshold value.

The "threshold value" is an interval at which an electrical bond can be formed between the energizing unit 10 and the stirring blade 1. The interval at which an electrical bond can be formed means an interval at which the phenomenon of electromagnetic induction can occur. In the heating and stirring device 100 according to the present embodiment, an electrical bond is formed between the energizing unit 10 and the stirring blade 1, so that an electromagnetic induction action can be utilized between the two, as will be described later. It will be possible. Therefore, the above expression "arranged in the vicinity of the stirring blade 1" can be rephrased as "arranged at a position where an electrical bond can be formed with the stirring blade 1."

Subsequently, with reference to FIG. 4, the electric circuit configuration of the heating and stirring device 100 according to the present embodiment will be described. With reference to FIG. 4, the high-frequency transformer 6 receives power from the AC power source 5 to generate high-frequency AC power. The power transmission coil 7 receives high-frequency AC power from the high-frequency transformer 6 and transmits power to the power-receiving coil 8 in a non-contact manner. When the power receiving coil 8 receives high frequency AC power from the power transmitting coil 7, the power receiving coil 8 supplies a high frequency current to the energized portion 10 through the conductive wires 9a and 9b. A direct current (DC) cut capacitor C1 is connected to the current path for supplying a high frequency current to the energizing unit 10.

When a high-frequency current is passed through the energizing unit 10, an alternating magnetic field that changes with time is generated. When this alternating magnetic field interlinks with the conductor portion of the stirring blade 1, an electromagnetic induction action is generated inside the conductor portion to induce an electromotive force. Due to this electromotive force, an eddy current (eddy current) is generated in the conductor portion. Eddy currents are converted to Joule heat by the electrical resistance of the conductor. The Joule heat generated in the conductor portion of the stirring blade 1 is transferred to the object to be processed 20 to heat the object to be processed 20.

As described above, in the heating / stirring device 100 according to the present embodiment, by heating the stirring blade 1, the object 20 to be processed is heated by receiving heat from the stirring blade 1. That is, the heating and stirring device 100 has a heat source for heating the object to be processed 20 inside the container 13. In the present specification, such a heating method is referred to as an "internal heating method". On the other hand, a heating method having a heat source for heating the object 20 to be processed outside the container 13 is referred to as an "external heating method".

[Explanation of external heating method]
In the conventional heating and stirring device, an external heating method has been generally adopted. FIG. 5A shows a configuration example of an external heating type heating / stirring device. In this configuration example, the conductive wire 32 is wound around the outer peripheral side of the wall surface of the container 30 containing the object to be processed 40. A power supply (not shown) is electrically connected to the conductive wire 32. The container 30 is, for example, a metal container. The stirring blade 34 is, for example, a disc turbine blade having a plurality of flat blades.

When a current is passed through the conductive wire 32 in this state, Joule heat is generated due to the electric resistance of the conductive wire 32. The Joule heat is proportional to the square value of the current flowing through the resistor. As shown by the broken line arrow in the figure, the generated Joule heat is transferred inward from the wall surface of the container 30, so that the object to be processed 40 is heated.

However, as a result of intensive research by the inventors of the present application, in the above-mentioned external heating method, when the viscosity of the object to be processed 40 becomes high, a new problem may arise that it becomes difficult to make the temperature of the object to be uniform uniform. I found. Then, as a new solution to the new problem, the inventors of the present application have come up with an internal heating method (see, for example, Non-Patent Document 1). Hereinafter, such a new problem and an internal heating method as a new solution to the new problem will be described.

[Explanation of internal heating method]
FIG. 5B shows a configuration example of an internal heating type heating / stirring device devised by the inventors of the present application. In this configuration example, the electromagnetic induction coil 38 is arranged below the bottom surface of the container 30 containing the object to be processed 40. The electromagnetic induction coil 38 is formed by winding a conductive wire such as copper in a coil shape. A high frequency power supply (not shown) is connected to the electromagnetic induction coil 38.

The container 30 is made of a non-conductive material and is made of, for example, an acrylic resin. The stirring blade 34 is made of a conductor and is made of, for example, stainless steel (SUS304). The stirring blade 34 is a disc turbine blade having the same structure as the stirring blade 34 of FIG. 5 (a).

When a high frequency current is passed through the electromagnetic induction coil 38, an alternating magnetic field is generated. An electromagnetic induction action is generated inside the stirring blade 34 in response to this alternating magnetic field, so that an eddy current is generated in the stirring blade 34. The eddy current is converted to Joule heat by the electrical resistance of the stirring blade 34. The Joule heat generated in the stirring blade 34 is transferred to the object to be processed 40 as shown by the broken line arrow in the drawing, thereby heating the object to be processed 40.

As described above, in the internal heating method, the object to be processed 40 is heated by electromagnetic induction heating of the stirring blade 34. That is, the stirring blade 34 can unify the stirring and heating of the object to be processed. In this way, better heat transfer characteristics can be obtained as compared with an external heating method in which stirring and heating of the object to be processed 40 are performed separately inside and outside the container 30. This makes it possible to promote uniform temperature of the object to be processed 40. The reason will be described below.

FIG. 6 shows the results of evaluating the temperature variation of the object to be processed for each of the external heating type heating and stirring device shown in FIG. 5 (a) and the internal heating type heating and stirring device shown in FIG. 5 (b). The horizontal axis of FIG. 6 shows the stirring Reynolds number Re, and the vertical axis shows the maximum variation temperature ΔTmax [K].

The stirring Reynolds number Re represents the ratio of the inertial force and the viscous force. The inertial force generally corresponds to the force that the fluid tries to keep moving. The viscous force generally corresponds to the force that tries to stop the fluid from moving. The stirring Reynolds number Re is a dimensionless number representing the effect of viscosity on the motion of the fluid to be treated in the container, and is defined by the following equation (1).

Re = ρ ・ n ・ d ² / μ… (1)
In the formula (1), ρ is the density of the object to be treated [kg / m ³ ], n is the rotation speed of the stirring blade [rps], d is the diameter of the stirring blade [m], and μ is the viscosity of the object to be processed [kg]. / (M · s)].

The stirring Reynolds number Re given by the formula (1) becomes a large value because the inertial force increases as the rotation speed n of the stirring blade increases. On the other hand, as the viscosity μ of the object to be treated increases, the viscous force increases, so that the stirring Reynolds number Re becomes a small value.

The maximum variation temperature ΔTmax of the object to be processed is determined at a plurality of measurement points where at least one of the horizontal distance from the main axis of the stirring blade 34 and the height from the bottom surface of the container 30 is different from each other during the heating and stirring operation. The temperature of the object to be processed 40 was measured, and the difference between the highest value and the lowest value among the obtained plurality of temperature measurement values was calculated.

In FIG. 6, k1 shows the relationship between the stirring Reynolds number Re and the maximum variation temperature ΔTmax in the heating and stirring device of the external heating type. k2 shows the relationship between the stirring Reynolds number Re and the maximum variation temperature ΔTmax in the heating and stirring device of the internal heating type.

As shown in FIG. 6, in both the external heating method and the internal heating method, the maximum variation temperature ΔTmax decreases as the stirring Reynolds number Re increases between the stirring Reynolds number Re and the maximum variation temperature ΔTmax. It was confirmed that there was a correlation.

Furthermore, when the above correlation was compared between the external heating method and the internal heating method, it was confirmed that the maximum variation temperature ΔTmax for the same stirring Reynolds number Re was smaller in the internal heating method than in the external heating method. ..

Here, the reason why the temperature variation of the object to be processed is smaller in the internal heating method than in the external heating method is the difference in the temperature distribution formed inside the container. Specifically, in the external heating method, the temperature of the object to be processed 40 rises locally near the wall surface of the container 30 around which the conductive wire 32 is wound, and the high temperature portion near the wall surface of the container 30 and the low temperature portion on the center side. A thick temperature boundary layer is formed between the and. On the other hand, in the internal heating method, since the stirring blade 34 serving as a heat source is rotating, the temperature boundary layer becomes thin, and as a result, it can contribute to uniform temperature of the object to be processed 40.

In the external heating method, the higher the viscosity μ of the object to be processed 40 or the lower the rotation speed n of the stirring blade 34 (that is, the smaller the stirring Reynolds number Re), the weaker the stirring force and the temperature boundary layer becomes. Since the thickness is increased, the temperature variation of the object to be processed 40 tends to be large. On the other hand, in the internal heating method, even if the stirring Reynolds number Re becomes small, it is possible to suppress the thickening of the temperature boundary layer, so that the temperature variation of the object to be processed 40 can be reduced.

Furthermore, the inventors of the present application have verified the relationship between the heat transfer characteristics and the temperature variation of the object to be treated by evaluating the heat transfer characteristics for each of the external heating method and the internal heating method. In the evaluation of the heat transfer characteristics, the heat conductance hA was calculated for each of the external heating method and the internal heating method, and the relationship between the calculated heat conductance hA and the stirring Reynolds number Re was derived.

Specifically, in the external heating method (see FIG. 5A), the heat transfer amount W1 in the heat transfer process between the wall surface of the container 30 and the object to be processed 40 is given by the following equation (2). The heat transfer amount W1 is determined by the input power from the power source to the conductive wire 32.

W1 = h1, A1, ΔT1 ... (2)
In formula (2), h1 indicates the heat transfer coefficient between the container 30 and the object to be processed 40, A1 indicates the surface area of the container 30, and ΔT1 is the average temperature of the wall surface of the container 30 and the average of the object to be processed 40. Indicates the temperature difference from the temperature. h1 and A1 represent thermal conductance in the external heating method.

On the other hand, in the internal heating method (see FIG. 5B), the heat transfer amount W2 in the heat transfer process between the stirring blade 34 and the object to be processed 40 is given by the following equation (3). The heat transfer amount W2 is determined by the input power from the high frequency power supply to the electromagnetic induction coil 38.

W2 = h2, A2, ΔT2 ... (3)
In the formula (3), h2 indicates the heat transfer coefficient between the stirring blade 34 and the object to be processed 40, A2 indicates the surface area of the stirring blade 34, and ΔT2 is the average temperature of the stirring blade 34 and the object to be processed 40. Shows the temperature difference from the average temperature. h2 and A2 indicate the thermal conductance in the internal heating method.

The relationship between the stirring Reynolds number Re and the thermal conductance hA was derived in each of the external heating method and the internal heating method. FIG. 7 shows the relationship between the stirring Reynolds number Re and the thermal conductance hA. The horizontal axis of FIG. 7 shows the stirring Reynolds number Re, and the vertical axis shows the thermal conductance hA.

In FIG. 7, the white rhombus shows the relationship between the stirring Reynolds number Re and the thermal conductance hA in the heating and stirring device of the external heating type. The black squares show the relationship between the stirring Reynolds number Re and the thermal conductance hA in the heating and stirring device of the internal heating type.

As shown in FIG. 7, it was confirmed that in the external heating method, the thermal conductance hA showed a substantially constant value regardless of the magnitude of the stirring Reynolds number Re. On the other hand, in the internal heating method, it was confirmed that there is a correlation between the stirring Reynolds number Re and the thermal conductance hA that the thermal conductance hA increases as the stirring Reynolds number Re increases.

Combining this correlation with the relationship between the stirring Reynolds number Re and the maximum variation temperature ΔTmax shown in FIG. 6, the larger the stirring Reynolds number Re, the larger the thermal conductance hA, while the smaller the maximum variation temperature ΔTmax. I understand.

Further, from FIG. 7, it was confirmed that the thermal conductance hA for the same stirring Reynolds number Re was larger in the internal heating method than in the external heating method. As described above, from FIG. 6, it is confirmed that the maximum variation temperature ΔTmax for the same stirring Reynolds number Re is smaller in the internal heating method than in the external heating method. These also apply to the correlation that the maximum variation temperature ΔTmax decreases as the thermal conductance hA increases.

From the above evaluation results, it is understood that the thermal conductance hA and the temperature variation of the object to be treated have a close relationship. The inventors of the present application consider that the internal heating method has a larger thermal conductance hA than the external heating method, so that the temperature variation of the object to be processed can be reduced. This is because when the stirring Reynolds number Re is small, for example, when the viscosity μ of the object to be processed is high, or when the rotation speed n of the stirring blade is low, the internal heating method is compared with the external heating method. It shows that the temperature uniformity is excellent.

The above relationship was obtained when a disc turbine blade was used for the stirring blade, but this relationship is also obtained when a stirring blade compatible with medium and high viscosity such as an anchor blade or Max Blend blade is used. It seems to hold true. That is, even when a stirring blade compatible with medium and high viscosities is used, the internal heating method has an advantage that the thermal conductance hA is large and therefore the temperature variation of the object to be processed is small as compared with the external heating method. It seems to be kept.

The inventors of the present application have further studied the internal heating method having the above-mentioned advantages. As a result, it has been found that in a configuration in which at least a part of the high-frequency current energizing portion 10 is brought into contact with the stirring blade 1 as shown in FIG. 1, excellent effects including miniaturization of the apparatus and improvement of heating efficiency can be obtained. rice field. Hereinafter, the main effects obtained by the present embodiment will be collectively described with reference to FIG.

FIG. 8 shows two types of heating and stirring devices as internal heating type heating and stirring devices. The heating and stirring device shown in FIG. 5 (b) is shown on the left side of the paper in FIG. The heating and stirring device according to the present embodiment shown in FIG. 1 is shown on the right side of the paper.

In the heating and stirring device of FIG. 5B, an electromagnetic induction coil, which is a current-carrying part of a high-frequency current, is arranged under the bottom surface of the container. In the following description, the heating / stirring device of FIG. 5B is also referred to as an “externally energizing type heating / stirring device” because the energizing portion is arranged outside the container. On the other hand, in the heating and stirring device according to the present embodiment, the current-carrying portion of the high-frequency current is in contact with the stirring blade inside the container. Therefore, the heating / stirring device according to the present embodiment is also referred to as an “internally energized heating / stirring device”. Hereinafter, the differences between these two types of heating and stirring devices will be described.

(1) Configuration of Energizing Unit The external energizing type heating / stirring device has a problem that the physique of the apparatus becomes large because the electromagnetic induction coil which is the energizing unit is arranged outside the container. For example, in the configuration in which the electromagnetic induction coil is arranged below the bottom surface of the container as shown in FIG. 5B, the physique of the device becomes large in the axial direction AX. In order to prevent the body of the device from becoming large, it is preferable to form the electromagnetic induction coil into a flat shape having a thin wall in the winding axis direction.

On the other hand, in the internally energized heating / stirring device, since the energized portion is housed inside the container, it is possible to prevent the device from becoming large in size. Further, the energizing portion may be formed of a conductor. Therefore, the energizing portion can take an appropriate shape according to the shape of the stirring blade so as to have a shape that easily contacts the stirring blade. A configuration example of the stirring blade and the energizing unit will be described later.

Further, since the energizing portion can be formed of a conductor such as an aluminum plate, the energizing portion can be easily brought into contact with the stirring blade by attaching the energizing portion to the stirring blade. Further, if the energized portion is made of a thin-film conductor, the stirring blade does not become large due to the contact of the energized portion.

(2) Positional restrictions on the stirring blade In the externally energized heating and stirring device, the stirring blade is mounted on the container in order to sufficiently link the alternating magnetic field generated by the electromagnetic induction coil located under the bottom surface of the container to the stirring blade. It is preferable to place it close to the bottom surface. As described above, it is necessary to determine the arrangement position of the electromagnetic induction coil according to the arrangement position of the electromagnetic induction coil, and the arrangement position of the stirring blade is likely to be restricted.

On the other hand, in the internal energization type heating and stirring device, since the energizing part and the stirring blade are in contact with each other, an electric bond is formed between the energizing part and the stirring blade, and as a result, the energizing part is generated. The magnetic field can be sufficiently linked to the stirring unit. Therefore, since the arrangement position of the stirring blade is not restricted, the degree of freedom in design can be increased. This is because, regardless of the position of the stirring blade, if the energizing portion is arranged in the vicinity of the stirring blade, the energizing portion and the stirring blade can be electrically coupled.

(3) Restriction on the shape of the stirring blade In the externally energized heating and stirring device, the stirring blade extends parallel to the bottom surface of the container in order to link the stirring blade with as much magnetic flux as possible perpendicular to the bottom surface of the container. It is preferable to have a flat surface. Therefore, it is preferable to use a stirring blade having a disk shape such as a disk turbine blade. As described above, it is necessary to determine the shape of the stirring blade according to the direction of the alternating magnetic field, and the shape of the stirring blade is likely to be restricted.

On the other hand, in the internal energization type heating and stirring device, as described above, since the energizing portion and the stirring blade are in contact with each other, the alternating magnetic field generated by the energizing portion can be sufficiently linked to the stirring portion. Therefore, as with the position of the stirring blade, the shape of the stirring blade is not restricted, so that the degree of freedom in design can be increased.

(4) Viscosity Restriction of Object to be Processed In a heating and stirring device, the rotation speed and shape of the stirring blade are generally determined according to the object to be processed and the purpose of stirring. For example, the disc turbine blades shown in FIGS. 5A and 5B have a stirring Reynolds number Re in the range of medium to high (for example, when the viscosity of the object to be processed is low, or the rotation speed of the stirring blade is high. When it is high), it is preferably used. On the other hand, the anchor blade shown in FIG. 1 is preferably used in a range in which the stirring Reynolds number Re is low to medium (for example, when the viscosity of the object to be processed is high or the rotation speed of the stirring blade is low). Be done.

However, in the externally energized heating and stirring device, as described in the item (3) Shape restriction of the stirring blade, it is preferable to use a stirring blade having a disk shape from the viewpoint of ease of performing electromagnetic induction heating. Therefore, it is preferable that the stirring Reynolds number Re is in the range of medium to high, and as a result, the viscosity of the object to be treated is preferably low.

On the other hand, in the internally energized heating / stirring device, as described above, since the shape of the stirring blade is not restricted, the viscosity of the object to be processed is not restricted. Therefore, even when the viscosity of the object to be processed is high, there is no restriction on the viscosity of the object to be processed because a stirring blade suitable for the viscosity can be used.

(5) Material restrictions of the container In the externally energized heating and stirring device, the container must be formed of a non-conductor in order to sufficiently interlink the alternating magnetic field generated by the electromagnetic induction coil outside the container with the stirring blade inside the container. There is. Therefore, the material of the container is likely to be restricted. Since a container made of a non-conductor is generally inferior in mechanical strength to a container made of a conductor such as metal, it may be disadvantageous to increase the size and pressure of the container.

On the other hand, in the internal energization type heating and stirring device, since the energizing portion is housed inside the container, the alternating magnetic field can be interlinked with the stirring blade without going through the container. Therefore, there are no restrictions on the material of the container, and the degree of freedom in design can be increased. Therefore, it is possible to easily cope with the increase in size and pressure of the container.

For example, by forming the container with a transparent material, it is possible to observe the state of the object to be treated during the heating and stirring treatment. Alternatively, at least a part of the container may be made of a conductor. In this way, the alternating magnetic field generated by the energized portion can be interlinked with the conductive portion of the container, so that the container can also be electromagnetically induced and heated.

(6) Heating efficiency Generally, the heating efficiency in a heating and stirring device is defined by the ratio of the amount of heat used for heating the object to be processed to the amount of heat input. The higher the heating efficiency, the smaller the amount of heat input can be, so that the power consumption can be reduced.

Here, when the heating efficiencies are compared between the external heating method (see FIG. 5A) and the internal heating method (see FIG. 5B) described above, the internal heating method has higher heating efficiency than the external heating method. can do.

Specifically, in the external heating method, the amount of heat input is used for heating the object to be processed and also for heating the container. On the other hand, in the internal heating method, the input heat amount is used for heating the object to be processed and also for heating the stirring blade.

As described above, the internal heating method has a larger thermal conductance hA than the external heating method. Therefore, even when the temperature difference between the stirring blade and the object to be processed is larger than the temperature difference between the container and the object to be processed, the same amount of heat as the amount of heat transferred from the container to the object to be processed is transferred from the stirring blade. It can be transmitted to the object to be processed. In other words, the heating temperature of the stirring blade may be lower than the heating temperature of the container as long as the same amount of heat is transferred to the object to be processed. Further, in the container and the stirring blade, the stirring blade generally has a smaller heat capacity than the container.

For these reasons, the amount of heat used to heat the stirring blades is smaller than the amount of heat used to heat the container. As a result, if the input heat amount is the same, the internal heating method can use a larger amount of heat for heating the object to be processed than the external heating method, so that the heating rate of the object to be processed can be increased. Conversely, in order to obtain the same heating rate, the internal heating method can reduce the amount of heat input as compared with the external heating method. Therefore, the power consumption can be reduced.

Further, in this internal heating method, when the heating efficiency is compared between the externally energized type and the internally energized type, the internal energized type can realize higher heating efficiency than the externally energized type for the following reasons. ..

FIG. 9 schematically shows a heat transfer path in the internal energization type heating and stirring device. In FIG. 9, the electrical connection or electrical coupling between the two components is shown by the dashed line, and the thermal connection between the components is shown by the solid line.

With reference to FIG. 9, in the internal energization type heating and stirring device, the power receiving coil 8 and the energizing unit 10 are electrically connected. Further, the energizing unit 10 and the stirring blade 1 are electrically coupled. As a result, the stirring blade 1 is electromagnetically induced and heated by the alternating magnetic field generated by the energizing unit 10 by receiving the supply of high-frequency current from the power receiving coil 8. Then, the object to be processed 20 is heated by the thermal connection between the stirring blade 1 and the object to be processed 20.

Further, the energizing unit 10 is thermally connected to the stirring blade 1 and thermally connected to the object 20 to be processed. When a high-frequency current is passed through the energizing unit 10, Joule heat is generated by the electric resistance of the energizing unit 10. The Joule heat generated by the energizing unit 10 is transferred to the stirring blade 1 and the object 20 to be processed, respectively.

As described above, according to the internal energization type, in addition to the Joule heat generated by the stirring blade 1, the Joule heat generated by the energizing portion 10 can be used for heating the object 20 to be processed. Therefore, if the input heat amount is the same, the internal energization type can use a larger amount of heat than the external energization type for heating the object 20 to be processed. Therefore, the heating rate of the object 20 to be processed can be increased. Conversely, in order to obtain the same heating rate, the internal energization type can reduce the amount of heat input as compared with the external energization type. Therefore, the heating efficiency is high and the power consumption can be reduced.

Further, the internal energization type can realize higher responsiveness to the target temperature in the temperature control of the object to be processed 20 as compared with the external energization type.

Here, as a method of generating Joule heat in the stirring blade 1, in addition to the configuration in which a high-frequency current is applied to the energized portion 10 to generate an eddy current in the stirring blade 1, as in the present embodiment, the stirring blade 1 is generated. It is possible to adopt a configuration in which a direct current is directly applied to 1 and Joule heat is generated by the electric resistance of the stirring blade 1.

However, in a configuration in which a direct current is applied to the stirring blade 1, it is necessary to increase the electric resistance of the conductor portion of the stirring blade 1 in order to obtain a sufficient amount of heat for heating the object 20 to be processed. Further, a high-voltage DC power supply is required to pass a large current through the stirring blade 1.

On the other hand, in the configuration in which the high-frequency current is applied to the energizing portion 10, the current does not flow evenly throughout the energizing portion 10 due to the skin effect of the high-frequency current, but is concentrated on or near the surface of the energizing portion 10. And flow. As a result, the substantial electrical resistance of the energizing unit 10 can be increased, so that a sufficient amount of heat can be generated in the energizing unit 10 even with a small current.

Further, when a current is directly applied to the stirring blade 1, there is a problem that it is difficult to secure a current path depending on the shape of the stirring blade 1. Therefore, the shape of the stirring blade 1 is restricted. On the other hand, according to the present embodiment, the current path can be easily formed by bringing the energizing portion 10 formed of the conductor into contact with the stirring blade 1.

As described above, according to the heating / stirring device according to the present embodiment, the energizing portion 10 made of a conductor can easily secure a high-frequency current path regardless of the shape of the stirring blade 1, and also has a high-frequency current. Due to the skin effect of the electric current, a large Joule heat can be generated in the energized portion 10 with a small electric current. Further, also in the stirring blade 1, since the eddy current is concentrated on or near the surface of the stirring blade 1 due to the skin effect, a large Joule heat can be generated in the stirring blade 1. As a result, the body size of the apparatus can be reduced and the heating efficiency can be improved as compared with the configuration in which the stirring blade 1 is energized with a direct current.

[Structure example of stirring blade and current-carrying part]
Hereinafter, a configuration example of a stirring blade and an energizing portion that can be applied to the heating and stirring device according to the present embodiment will be described with reference to FIGS. 10 to 16. As described with reference to FIG. 8, the internally energized heating / stirring device according to the present embodiment has no restrictions on the position and shape of the stirring blades. Therefore, a stirring blade having an appropriate shape can be used according to the viscosity of the object to be processed and the rotation speed of the stirring blade.

First, a configuration example of a stirring blade composed of a disc turbine blade and a current-carrying portion will be described with reference to FIGS. 10 and 11. The disc turbine blade is a stirring blade mainly used for stirring a low-viscosity object to be processed.

FIG. 10A is a view of the stirring blade 1 viewed from above the main shaft 1a. 10 (b) is a cross-sectional view taken along the line XX in FIG. 10 (a).

As shown in FIG. 10A, the stirring blade 1 has a disk shape in which a plurality of blades are arranged along the outer periphery thereof. The energizing portion 10 is wound around the outer peripheral surface of the stirring blade 1. In the energizing unit 10, the conductive unit is, for example, a conductive coil. The conductive coil is made of, for example, aluminum. The insulator 12 that covers the outer periphery of the conductor portion is made of, for example, alumina.

With reference to FIG. 10B, the energizing portion 10 is arranged in the groove portion 1b formed on the outer peripheral surface of the stirring blade 1. After winding the energizing portion 10, the groove portion 1b is impregnated with an insulating material such as a thermosetting resin to bring the energizing portion 10 into contact with the stirring blade 1 and smooth the outer peripheral surface of the stirring blade 1. can do. Alternatively, a conductive coil coated with insulation may be embedded in the groove portion 1b.

When the energizing portion 10 is wound around the outer peripheral surface of the stirring blade 1, the surface of the stirring blade 1 is projected, so that the original shape of the stirring blade may be impaired. In such a case, the power number of the stirring blade may deviate from the design value, and the stirring power may also deviate from the design value. As shown in FIG. 10B, by embedding the energizing portion 10 in the stirring blade 1, the stirring blade 1 and the energizing portion 10 are brought into contact with each other without impairing the original shape of the stirring blade 1. Can be done.

FIG. 11A is a view of the stirring blade 1 viewed from above the main shaft 1a. 11 (b) is a cross-sectional view taken along the line XI-XI in FIG. 11 (a).

With reference to FIG. 11A, the energizing portion 10 is attached to the flat surface portion of the surface of the stirring blade 1. In the energizing portion 10, the conductive portion is, for example, a conductive tape. The conductive tape is made of, for example, aluminum. The insulator that covers the outer circumference of the conductor portion is made of, for example, alumina.

As shown in FIG. 11B, the energizing portion 10 is arranged in the groove portion 1b formed in the flat surface portion of the surface of the stirring blade 1. By impregnating the groove portion 1b with a thermosetting resin after the energizing portion 10 is bonded, the energizing portion 10 can be brought into contact with the stirring blade 1 and the surface of the stirring blade 1 can be smoothed. Alternatively, a conductive coil coated with insulation may be embedded in the groove portion 1b. As a result, the original shape of the stirring blade 1 can be maintained.

Next, with reference to FIGS. 12 to 14, a configuration example of the stirring blade and the energizing portion made of the Max Blend blade will be described. The Max Blend blade is a stirring blade mainly used for stirring a medium-viscosity object to be processed.

FIG. 12A is a view of the stirring blade 1 viewed from a direction perpendicular to the spindle 1a. FIG. 12B is a partial perspective view seen from the direction of arrow XII1 in the drawing. FIG. 12 (c) is a cross-sectional view taken along the line XII2-XII2 in the drawing.

With reference to FIG. 12A, the stirring blade 1 has a flat plate shape in which a plurality of through holes are formed in a grid pattern. The energizing portion 10 is wound around the side surface of the flat plate portion of the stirring blade 1. In the energizing unit 10, the conductive unit is, for example, a conductive coil.

With reference to FIGS. 12 (b) and 12 (c), the energizing portion 10 is arranged in the groove portion 1b formed on the side surface of the flat plate portion of the stirring blade 1. After winding the energizing portion 10, the groove portion 1b is impregnated with an insulating material such as a thermosetting resin to bring the energizing portion 10 into contact with the stirring blade 1 and smooth the side surface of the stirring blade 1. be able to. As a result, the original shape of the stirring blade 1 can be maintained. Alternatively, a conductive coil coated with insulation may be embedded in the groove portion 1b.

FIG. 13A is a view of the stirring blade 1 viewed from a direction perpendicular to the spindle 1a. FIG. 13B is a cross-sectional view taken along the line XIII-XIII in the drawing.

With reference to FIG. 13A, the energizing portion 10 is attached to the surface of the flat plate portion of the stirring blade 1. In the energizing portion 10, the conductive portion is, for example, a conductive tape. As shown in FIG. 13B, the energizing portion 10 is arranged in the groove portion 1b formed on the surface of the flat plate portion of the stirring blade 1. After the energizing portion 10 is bonded, the groove portion 1b is impregnated with an insulating material such as a thermosetting resin so that the energizing portion 10 is brought into contact with the stirring blade 1 and the surface of the stirring blade 1 is smoothed. can. As a result, the original shape of the stirring blade 1 can be maintained. Alternatively, a conductive coil coated with insulation may be embedded in the groove portion 1b.

FIG. 14A is a view of the stirring blade 1 viewed from a direction perpendicular to the spindle 1a. 14 (b) and 14 (c) are cross-sectional views taken along the line XIV-XIV in the figure.

With reference to FIG. 14 (a), the stirring blade 1 includes a first portion 1A and a second portion 1B. The first portion 1A and the second portion 1B are arranged so as to face each other along the axial direction AX. In the example of FIG. 14, the first portion 1A and the second portion 1B are formed by dividing the flat plate portion of the stirring blade 1 into two along the axial direction AX. At least one of the first portion 1A and the second portion 1B has a conductor portion (first conductor portion) formed at least in a part thereof.

As shown in FIG. 14B, the energizing portion 10 is arranged between the first portion 1A and the second portion 1B. In the energizing portion 10, the conductive portion is, for example, a conductive tape. For example, by attaching the energizing portion 10 to the first portion 1A and then attaching the first portion 1A and the second portion 1B, the energizing portion 10 can be brought into contact with the stirring blade 1. The energizing portion 10 may be embedded in the first portion 1A.

The energizing unit 10 may be a single-wound coil in which the number of coil turns is 1, as shown in FIG. 14 (b), and the number of coil turns may be as shown in FIG. 14 (c). It may be a multi-winding coil in which is 2 or more.

According to the configuration example shown in FIG. 14, by sandwiching the energizing portion 10 between the first portion 1A and the second portion 1B, the Joule heat generated by the energizing portion 10 is transferred to the first portion 1A and the second portion 1B. Can be transmitted evenly to. As a result, the heat transfer coefficient between the stirring blade 1 and the object to be processed can be increased, and as a result, the heating efficiency can be improved.

Further, in the configuration example shown in FIG. 14, since the energizing unit 10 functions to reinforce the strength of the stirring blade 1, the robustness of the stirring blade 1 can be improved.

Finally, with reference to FIGS. 15 and 16, a configuration example of a stirring blade composed of a helical blade and an energized portion will be described. The helical blade is a stirring blade mainly used for stirring a highly viscous object to be processed.

FIG. 15 is a view of the stirring blade 1 as viewed from a direction perpendicular to the main axis. With reference to FIG. 15, the stirring blade 1 has strip-shaped blades arranged in a spiral shape. The energizing portion 10 is wound around the outer peripheral surface of the band-shaped blade. In the energizing unit 10, the conductive unit is, for example, a conductive coil. The energizing portion 10 is arranged in a groove portion (not shown) formed on the outer peripheral surface of the stirring blade 1. By impregnating the groove portion with the thermosetting resin after winding the energizing portion 10, the energizing portion 10 can be brought into contact with the stirring blade 1 and the outer peripheral surface of the stirring blade 1 can be smoothed. Alternatively, a conductive coil coated with insulation may be embedded in the groove.

A conductor portion (third conductor portion) is formed in at least a part of the container 13. The conductor portion of the container 13 is preferably formed at a position close to the current-carrying portion 10. The position close to the energizing unit 10 means a position capable of electrically coupling with the energizing unit 10 and sufficiently interlinking the alternating magnetic field generated by the energizing unit 10. In the example of FIG. 15, it is preferable to arrange the conductor portion on the wall surface of the container 13 so as to face the energizing portion 10. In this way, the alternating magnetic field generated by the energizing portion 10 is interlinked with the conductor portion of the container 13 to heat the stirring blade 1 and the container 13 can be electromagnetically induced heated. Therefore, the heating efficiency can be further improved.

FIG. 16A is a view of the stirring blade 1 viewed from a direction perpendicular to the main axis. FIG. 16B is a cross-sectional view taken along the line XVI-XVI in the drawing. With reference to FIGS. 16A and 16B, the energizing portion 10 is attached to the surface of the spiral blade. In the energizing portion 10, the conductive portion is, for example, a conductive tape. Similar to FIGS. 11 and 13, in FIG. 16, by arranging the energizing portion 10 in the groove formed on the surface of the blade, the original shape of the stirring blade 1 can be maintained. For example, after arranging the energizing portion 10 in the groove portion, the groove portion may be impregnated with an insulating material such as a thermosetting resin. Alternatively, a conductive coil coated with insulation may be embedded in the groove.

[Configuration example of power supply unit]
In the above-described embodiment, the configuration in which the AC power supply 5 supplies power to the current-carrying unit 10 in a non-contact manner in the power-feeding unit 4 for supplying the high-frequency current to the current-carrying part 10 has been described. The same effect as that of the embodiment can be obtained as the configuration in which the device is brought into contact with the device.

FIG. 17 shows a configuration of a modified example of the heating / stirring device according to the present embodiment. FIG. 17 shows a cross-sectional structure of the heating / stirring device 100 according to the modified example along the axial direction AX.

The basic configuration of the heating / stirring device 100 according to this modified example is the same as that of the heating / stirring device 100 shown in FIG. 1 except for the power feeding unit 4. In this modified example, the power feeding unit 4 has a slip ring 16 instead of the power transmitting coil 7 and the power receiving coil 8. The slip ring 16 includes a carbon brush (not shown) electrically connected to the high frequency transformer 6, and by bringing the carbon brush into surface contact with the energizing portion 10 which is a rotating body, the energizing portion 10 is brought into high frequency. It is configured to be able to supply current.

[Application example of heating and stirring device]
In the above-described embodiment, the configuration in which the heating / stirring device of the present invention is applied to the sludge treatment device that recovers methane gas as an energy source from the sewage sludge has been described. Not limited to it, it can be applied to various fields. For example, a fermentation processing device that ferments organic substances, a polymerization reactor that combines monomers to produce a giant polymer substance, a evaporator that removes a solvent from a high-viscosity substance, removes a monomer and volatilizes it, and a cooker that heats and stirs ingredients. The heating and stirring device of the present invention can be applied to the above.

It should be considered that the embodiments disclosed this time are exemplary in all respects and not restrictive. The scope of the present invention is shown by the scope of claims rather than the above description, and it is intended to include all modifications within the meaning and scope equivalent to the scope of claims.

1,34 Stirrer blade, 1a spindle, 1b groove, 1A first part, 1B second part, 2 rotation shaft, 3,15 sealing member, 4 power supply part, 5 AC power supply, 6 high frequency transformer, 7 transmission coil , 8 Power receiving coil, 9a, 9b, 32 Conductive wire, 10 Currenting part, 11 Conductor part, 12 Insulator, 13,30 Container, 14 Lid part, 16 Slip ring, 20,40 Object to be processed, 38 Electromagnetic induction coil , 100 heating and stirring device.

Claims (5)

A heating and stirring device for heating and stirring an object to be processed contained in a container.
A stirring blade rotatably arranged in the container and at least a part of which is formed as a first conductor portion.
It has a second conductor portion arranged in the container and fixed to the stirring blade, and an insulator provided between the first conductor portion and the second conductor portion, and the stirring is performed. The energizing part that rotates with the wings and
It is provided outside the container and includes a feeding unit that supplies a high-frequency current to the energizing unit.
In the container, at least a part of the energizing portion may be arranged in contact with the stirring blade to interlink the alternating magnetic field generated by the second conductor portion with the first conductor portion. A heating and stirring device that is possible. The second conductor portion includes a conductive coil wound around the outer circumference of the stirring blade.
The heating and stirring device according to claim 1, wherein the conductive coil is arranged in a groove formed on the outer periphery of the stirring blade. The second conductor portion includes a conductive tape attached to the surface of the stirring blade.
The heating and stirring device according to claim 1, wherein the conductive tape is arranged in a groove formed on the surface of the stirring blade. The stirring blade includes a first flat plate portion and a second flat plate portion arranged to face the first flat plate portion.
At least one of the first flat plate portion and the second flat plate portion is formed as the first conductor portion .
The heating and stirring device according to claim 1, wherein the energizing portion is arranged between the first flat plate portion and the second flat plate portion. At least a part of the container is formed as a third conductor portion, and the container is formed.
By arranging the third conductor portion so as to face the energized portion, it is possible to interlink the alternating magnetic field generated by the second conductor portion with the third conductor portion. It is, heating and stirring device according to any one of claims 1 to 4.

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