JP2004141474A - Heat treatment equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To eliminate treatment temperature restriction in a rotary type heat treatment using superheated steam. <P>SOLUTION: A steam superheating mechanism 3b for feeding superheated steam to a treatment chamber 1 operated while rotating is directly disposed in the treatment chamber 1 and is operated while rotating along with the treatment chamber 1. This constitution can dispense with a rotary joint from a superheated steam feed route and dissolve the treatment temperature restriction derived from the heat resistance of the rotary joint. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a rotary heat treatment apparatus that includes a treatment chamber that rotates while containing or passing a workpiece, and that heats the workpiece by supplying superheated steam to the treatment chamber. This heat treatment can be performed without an application limit related to the treatment temperature.
[0002]
[Prior art]
Conventionally, this type of heat treatment is performed for the purpose of drying, volume reduction, cooking, incineration, and the like, for example, to-be-treated objects such as waste oil, waste plastic, food materials, and garbage. If the basic structure of the apparatus which performs this heat processing is shown typically, it will become like FIG.
[0003]
In FIG. 1, reference numeral 1 denotes a processing chamber supported and rotated by a turning roller 2. The turning roller 2 is connected to a motor (not shown) via a speed change mechanism (not shown). 3 is a superheated steam generating mechanism, a steam generating mechanism (boiler) 3a for heating water to generate steam not exceeding 100 ° C, and steam for heating this steam to a target temperature exceeding 100 ° C. And an overheating mechanism 3b. Then, the superheated steam output from the superheated steam generation mechanism 3 is supplied to the processing chamber 1 through the rotary joint 4 and subjected to heat treatment, and then discharged from the exhaust pipe 5 to the outside of the system.
[0004]
An example of an apparatus similar to the basic configuration of FIG. 1 is disclosed in Patent Documents 1 and 2 below. According to such a rotary heat treatment apparatus using superheated steam as a heat source, heat treatment can be performed by applying evenly superheated steam having a large heat content, excellent heating capability, and clean treatment to the workpiece. That is, as described in Patent Documents 1 and 2 below, heat treatment such as food cooking that does not allow contamination of an object to be processed can be performed with high efficiency and uniform processing quality.
[0005]
[Patent Document 1] Japanese Patent Application Laid-Open No. 2000-135061 (Page (8), FIGS. 1 and 2)
Japanese Patent Laid-Open No. 2000-135167 (Page (7), FIGS. 2 and 3)
[0006]
[Problems to be solved by the invention]
A rotary heat treatment apparatus using superheated steam as a heat source has the outstanding advantages as described above. However, this heat treatment apparatus has a limit in application. This is the limit that the heat treatment temperature is limited by the heat resistance of the rotary joint because the superheated steam is fed from the superheated steam generation mechanism 3 to the processing chamber 1 through the rotary joint 4. Incidentally, the maximum usable temperature of a commercially available rotary joint is only 200 ° C. in the case of continuous use. For example, the examples of Patent Documents 1 and 2 disclose heat treatment with superheated steam up to 350 ° C., but the treatment time is as short as 30 seconds. There is little thermal deterioration, and the seal member can be replaced with a load that is slightly more frequent.
[0007]
However, in the case of high-temperature heat treatment that requires continuous heating at 300 ° C. or higher, the superheated steam is a high-dew point gas that has a stronger thermal degradation effect than a simple high-temperature gas (nitrogen gas, etc.). A joint cannot be obtained, and therefore, a rotary heat treatment with superheated steam cannot be applied to such a heat treatment.
[0008]
That is, it has been a problem to provide a rotary heat treatment apparatus using superheated steam that can be applied to a high heat treatment such as continuous heating at 300 ° C. or higher.
[0009]
[Means for Solving the Problems]
The present invention has been made to solve such a problem, and the heat treatment apparatus of the present invention includes a processing chamber that rotates while containing or passing an object to be processed. In a heat treatment apparatus that heats the workpiece by supplying superheated steam from a superheated steam generation mechanism that includes a generation mechanism and a steam superheat mechanism, the steam superheat mechanism is directly connected to the processing chamber. The structure is configured to operate while rotating together with the processing chamber.
[0010]
According to this configuration, there is no rotary joint on the path for supplying superheated steam to the processing chamber. Therefore, the application limit of the heat treatment apparatus related to the heat resistance of the rotary joint is eliminated, and the high heat heating is performed. The present invention has been solved because the present invention can be applied to processing.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Next, an embodiment of the heat treatment apparatus according to the present invention will be described.
[0012]
FIG. 2A is a schematic partial cross-sectional view of the heat treatment apparatus according to the present embodiment, and FIG.
[0013]
In FIG. 2, reference numeral 1 denotes a processing chamber, and 3 b a steam superheating mechanism, both of which are directly connected and integrated, and are supported and driven by a plurality of turning rollers 2 to rotate together. This rotation is a rotation in only one direction according to the content of the heat treatment performed in the processing chamber 1, or a swinging rotation that is rotated in place of the forward direction and the backward direction. The turning roller 2 is driven by a motor with a transmission (not shown). Reference numeral 1 a denotes a lid opening for taking a processing object into and out of the processing chamber 1. The means for supporting and rotating the processing chamber 1 and the like is not limited to the above-mentioned turning roller system. For example, the processing chamber 1 and the like are supported by an arm with an axis and rotated around the axis. Other means may be used.
[0014]
3a is a steam generation mechanism (boiler), which is connected to the steam superheater mechanism 3b via a tightly sealed rotary joint 4A having a usable upper limit temperature of 150 ° C., and the mechanism 3a, 3b The generating mechanism 3 (see FIG. 1) is configured. That is, although the rotary joint (4 in FIG. 1) connecting the steam superheating mechanism 3b and the processing chamber 1 is eliminated by the present invention, the rotary joint 4A is required as a compensation. However, since the water flowing through the rotary joint 4A is at most 100 ° C. fed from the water vapor generating mechanism 3a, there is no problem if the 150 ° C. rotary joint 4A is used.
[0015]
A chimney 5A is connected to the processing chamber 1 through a labyrinth (maze) seal-type simple rotary joint 4B and an exhaust pipe 5 in order, and guides the exhaust of the heat treatment to the upper part of the system. That is, in order to deploy the stationary chimney 5 </ b> A that does not rotate, the rotary joint 4 </ b> B needs to be disposed in the exhaust portion where the water vapor temperature is not so much lower than in the processing chamber 1. However, the rotary joint provided here is close to the exhaust discharge port, and even with a simple seal of the labyrinth level, the leakage of water vapor can be prevented. Therefore, the simple rotary joint 4B is sufficient. And the labyrinth seal part is comprised only with the metal material, and the trouble concerning the heat resistance as mentioned above does not arise at all. The chimney 5A may be omitted depending on the content of the heat treatment performed in the processing chamber 1.
[0016]
In the apparatus of FIG. 2, induction coils 6A, 6B, and 6C for induction heating the passages 7A, 7B, and 7C of fluid (water vapor, splashed water, and the like) are provided in the processing chamber 1, the steam heating mechanism 3b, and the chimney 5A, respectively. The induction coils 6A, 6B, and 6C are provided with high-frequency energization from a high-frequency power supply device (not shown), so that the induction coils 6A, 6B, and 6C are guided to the passages 7A, 7B, and 7C serving as heat input portions of the processing chamber 1 and the like. An electric current (eddy current) is generated to heat the heated part by induction. Therefore, the material of the tubular body constituting the passages 7A, 7B, and 7C needs to be a conductive material such as metal or conductive ceramics. In this embodiment, the tubular body is made of nonmagnetic austenitic stainless steel. It is said. In this way, when a nonmagnetic conductive tubular body is used, the steam superheating shown in FIG. 2C is a front view of the heat treatment apparatus of another embodiment similar to the apparatus of FIG. Even when a plurality of tubular bodies 3baa are convergingly arranged from the outer edge region to the inner back region as in the section, the electromagnetic induction action by the induction coil 6B extends evenly to the tubular body 3baa in the inner back region, The body 3baa can be uniformly induction-heated. Even when the conductive tubular body is a ferromagnetic material such as ferritic stainless steel, the above-described effect due to the non-magnetic material is similarly exhibited in a case where the conductive tubular body is operated at a temperature exceeding its magnetic transformation point.
[0017]
Here, the purpose and function of deployment of each of the induction coils 6A, 6B, 6C will be described as follows.
[0018]
First, the induction coil 6 </ b> A of the processing chamber 1 is arranged as a heating means for adjusting the temperature distribution in the processing chamber 1. For example, the induction coil 6A is energized with high frequency to inductively heat the vessel wall 1b of the processing chamber 1 and raise the temperature to a temperature equivalent to that of superheated steam, thereby increasing the temperature in the processing chamber 1 over the vicinity of the vessel wall 1b. Can be uniform. This measure is more important in the operation that brings about temporal uniformity as well as spatial uniformity of the processing temperature. For example, if superheated steam is supplied after raising the temperature of the device wall 1b to the above temperature, condensation that should occur on the device wall 1b where the temperature has not increased can be prevented, and the rise to the processing temperature can be accelerated. Furthermore, by performing the induction heating so that the object to be processed in the processing chamber 1 is also preheated, the rise to the processing temperature is further accelerated, and a heat treatment with a constant processing temperature can be performed. In response to directing that the workpiece is also heated from the side of the vessel wall 1b for preheating or supplementary heat during the heating process, the inner wall surface 1ba of the vessel wall 1b is radiated with infrared radiation as the temperature rises. It is useful to have a surface treatment that increases the rate. In this embodiment, the surface treatment is a treatment in which the vessel wall 1b is previously oxidized with superheated steam to form a hydrous oxide film. This coating is black, and its material and color tone combine to make the infrared emissivity of the vessel wall surface 1ba more than 10 times higher than that of the bare metal surface. (Radiation heating) action becomes remarkable.
[0019]
Although the heating of the processing chamber wall 1b by induction heating has been described above, this heating is performed by using a heating means other than induction heating, for example, a rotating processing chamber using a gas burner having a straight flame opening. The structure that heats one wall 1b is also useful as an inexpensive high-efficiency heating means. Moreover, although the heating of the container wall 1b is a desirable component of the apparatus of the present invention, it may be omitted depending on the content of the heat treatment.
[0020]
Next, the induction coil 6B of the steam superheating mechanism 3b is arranged as a heating means for heating the steam, which is an object to be heated, to a temperature higher than 100 ° C. in the steam superheating mechanism 3b. In this embodiment, as shown in FIG. 2, a steam passage for heating steam is a steam passage in which a plurality of tubular bodies 3baa having a small diameter (a diameter sufficiently smaller than the outer diameter of the entire mechanism) are arranged in parallel. The group 3ba is configured, and the water vapor passage group 3ba is induction-heated by an induction coil 6B disposed around the outer periphery thereof. Each small-diameter tubular body 3ba is provided with a strip (not shown) made of a stainless steel plate that is bent in a zigzag shape. By the provision of this strip, the water vapor in the small-diameter tubular body 3ba When the flow is disturbed (including turbulent flow), the efficiency of transmission of the heat of the tube wall of the small-diameter tubular body 3ba, which has been input by induction heating, to the water vapor inside is significantly improved. In addition, although the above-mentioned heating from the outside is indispensable about this steam superheating mechanism, the heating means for that purpose is not limited to the induction heating. For example, it may be performed by gas flame heating.
[0021]
Similarly to the steam superheating mechanism 3b, the steam generating mechanism 3a is also required to be heated from the outside. As the heating means, induction heating in a form according to the induction heating of the steam superheating mechanism 3b can be employed.
[0022]
Next, the induction coil 6 </ b> C of the chimney 5 </ b> A is for detoxifying the steam-based exhaust gas containing the pyrolysis gas and the like by-produced by the heat treatment discharged from the chimney 5 </ b> A at a high temperature. Therefore, in order to efficiently transfer heat from the chimney tube wall to the exhaust in this heating, the chimney 5A is configured by arranging a plurality of small-diameter tubular bodies in parallel according to the embodiment of the water vapor superheating mechanism 3b (not shown). And a baffle is provided (not shown) in each small-diameter tubular body. As the baffle, a steel fiber surface of a steel fiber bundle that has been subjected to a surface treatment having a catalytic function (such as nickel plating) is used. That is, the baffle not only improves the heat transfer efficiency but also has a function of promoting the thermal decomposition and detoxification of harmful components in the exhaust gas. In consideration of the fact that the thermal decomposition and detoxification may involve oxidation of harmful components, an openable small hole or the like for allowing the air for oxidation to flow into the chimney 5A may be provided in the chimney 5A. Good. The induction coil 6C can be replaced by other exhaust heating means such as gas flame heating. Further, depending on the content of the heat treatment, the exhaust heating means itself or the chimney 5A as described above can be omitted.
[0023]
As described above, the measure of performing induction heating by arranging the induction coil 6A or the like in the processing chamber 1 or the like is used to accurately and quickly adjust the temperature distribution in the processing chamber 1 or the time-series temperature program. Very useful.
[0024]
Whether the induction coil 6A or the like needs to be cooled depends on the power required to be input. When cooling is not required, the induction coil 6A, etc. can be constructed by winding a litz wire (conducting wire with a copper thin wire with insulation coating), a normal twisted conducting wire, a copper single wire with a required outer diameter or a copper strip. That's fine. In particular, since a high-frequency current flows through the cross section of the litz wire, the increase in effective resistance when energized at a high frequency is small, and the copper loss is small. Therefore, it is possible to energize without cooling with a thinner wire outer diameter than other wires, which is preferable in terms of both convenience and power efficiency. Next, when cooling is necessary, the induction coil 6A and the like are formed by winding a copper tube, a brass tube, or a copper or brass strip with a tube made of the same material and brazed to the conductor, What is necessary is just to utilize the hollow part of a tube as a cooling water channel. Furthermore, a composite conductor in which the litz wire is inserted into a hollow portion of a flexible sheath such as a plastic tube and the hollow portion is used as a cooling water channel is also useful. This composite conductor is flexible and suitable for in-situ winding. Here, the cooling water that has flowed through the cooling water channel and finished cooling the induction coil 6A and the like is preferably input to the steam generation mechanism 3a and reused as steam raw material water. This is because cooling water that has been cooled can be reused not only as a water resource but also including sensible heat accumulated during cooling. This is because it contributes to reduction.
[0025]
FIG. 2 shows an embodiment in which a solenoid type (bend type) coil is used as the induction coil 6A or the like, but the processing chamber 1 or the steam superheater 3b that operates while rotating is shown in FIG. 4, a saddle type coil 61 and a hairpin type coil 62 as schematically shown in FIG. In both coils, the portions 61a and 62a located along the heated portion function as induction working conductors, and induction heating is performed on the linear regions facing each other. Then, due to the rotation of the processing chamber 1 etc., the wall of the processing chamber 1 etc. is heated over the entire circumference. Incidentally, the solenoid type coil is excellent in induction heating efficiency. On the other hand, according to the saddle type coil and hairpin type coil, the operation of the processing chamber 1 etc. in the apparatus of the present invention (inserting / removing the object to be heated and the entire attachment / detachment) are easy. become.
[0026]
Insulating materials (calcium silicate, glass, alumina, etc.) are gathered on the outer peripheral side of the treatment chamber 1 etc. that is induction-heated by the induction coil 6A etc. or 61 etc. so as to be separated from the induction coils 6A, 61 etc. It is desirable to prevent heat radiation from the processing chamber 1 or the like by disposing the heat insulating layers 8A, 8B, and 8C made of a mat or an alumina molded body. This is because the desired induction heating can be performed with less power consumption.
[0027]
As mentioned above, although the heat processing of the to-be-processed object was demonstrated taking the example of embodiment of the batch type (form to which a to-be-processed object is enclosed in a process chamber) as an example, embodiment of this invention apparatus is not limited to this, Continuous type ( It is good also as an apparatus of the form which heat-processes by the form which carries out a process, supplying a to-be-processed object sequentially in a processing chamber, and letting it pass.
[0028]
【The invention's effect】
The heat treatment apparatus of the present invention is a device for heat-treating an object to be treated with superheated steam in a processing chamber that operates while rotating, and is a steam having a subsequent function of a superheated steam generation mechanism for supplying superheated steam to the processing chamber. The overheating mechanism is arranged in a form that is directly connected to the processing chamber and is operated while rotating together with the processing chamber.
[0029]
In the conventional rotary heat treatment apparatus using superheated steam, the superheated steam is supplied from the superheated steam generation mechanism to the processing chamber via the rotary joint. Therefore, due to the heat-resistant temperature of the rotary joint, The temperature at which the above heat treatment can be performed is limited, and there are restrictions on the application.
[0030]
In the apparatus of the present invention, it is not necessary to arrange the rotary joint in the superheated steam output section where the organic material constituting the rotary joint is severely deteriorated. It was solved. The expansion of the application of heat treatment with superheated steam is desirable for various demands such as recycling of waste, detoxification of harmful substances, and the creation of high-value materials for various resources. is there.
[Brief description of the drawings]
FIG. 1 is a diagram showing a schematic configuration of a conventional rotary heat treatment apparatus.
2A is a diagram showing a schematic configuration of a rotary heat treatment apparatus according to an embodiment of the present invention, FIG. 2B is a front view of the steam superheater shown in FIG. (C) is an AA arrow front view of another form of a water vapor superheated part.
FIG. 3 is a diagram showing a first other example of the induction heating coil used in the rotary heat treatment apparatus according to the embodiment of the present invention.
FIG. 4 is a diagram showing a second other example of the induction heating coil used in the rotary heat treatment apparatus according to the embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Processing chamber 1a ... Covered opening 1b ... Unit wall 1ba of processing chamber 1 ... Inner wall surface 2 of unit wall 1b ... Turning roller 3 ... Superheated steam generation mechanism 3a ... Steam generation mechanism (boiler)
3b ... Steam overheating mechanism 3ba ... Steam passage group 3baa ... Tubular bodies 4A, 4B ... Rotary joint 5 ... Exhaust pipe 5A ... Chimneys 6A, 6B, 6C ... Induction coils 7A, 7B, 7C ... Fluid passages 8A, 8B, 8C ... Thermal insulation layer

Claims (4)

A processing chamber is provided that rotates while containing or passing a workpiece, and the processing chamber is configured to supply superheated steam from a superheated steam generation mechanism including a steam generation mechanism and a steam superheating mechanism. In the heat treatment apparatus for heat treatment,
The water vapor superheating mechanism is directly connected to the processing chamber and operates while rotating together with the processing chamber. The heat treatment apparatus according to claim 1, wherein the water vapor generating mechanism is connected to the water vapor superheating mechanism via a rotary joint. The heat treatment apparatus according to claim 1 or 2, wherein a chimney for discharging the exhaust of the processing chamber upward is provided in the processing chamber via a rotary joint. At least one of the processing chamber, the steam generation mechanism, the steam superheating mechanism, and the chimney is configured by using a conductive tubular body in the steam passage, and the tubular body is induction-heated outside the tubular body. The heat treatment apparatus according to claim 3, wherein an induction coil is provided.

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