JPH1048397A - Method and device for calculation treatment of radioactive solid waste - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable stable and safe operation even when inorganic and organic substances are intermingled by installing a water cooling jacket to restrain the heating quantity for a waste and cooling the atmosphere around it to curb the rate of temperature rise. SOLUTION: A heating chamber is constituted of a water cooling jacket 1 and an induction coil 2 so as to restrain the heating quantity for a waste X and cool the atmosphere around them. Then, the temperature of the waste X in the jacket 1 is raised slowly through the induction heating of the coil 2 while it is monitored by a waste temperature detector 13. Subsequently, the concentration of oxygen and carbon dioxide contained in a pyrolysis gas of organic substances in the waste X is monitored by an oxygen concentration detector 11 and a carbon dioxide concentration detector 12. In this process, a coil 2 is operated to stop or weaken the heating, when it is judged that the oxygen concentration is lowered abnormally to cause incomplete combustion. Thereupon, the heating is finished by judging that a calculation treatment for pyrolyzing organic substances has finished at the time when the concentration of carbon dioxide has lowered from a fluctuating condition to a steady state.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a calcining method and apparatus for heating radioactive solid waste and thermally decomposing organic substances in the waste, and particularly to radioactive solid waste in which inorganic substances and organic substances are mixed. TECHNICAL FIELD The present invention relates to a calcining method and apparatus for preventing an unstable combustion state.

[0002]

2. Description of the Related Art Among radioactive wastes generated from nuclear facilities such as a nuclear power plant, solid wastes are disposed in a shallow layer or a deep layer. Normally, solid waste is composed of inorganic waste (concrete and metal equipment and structural materials, fuel cladding tubes, fuel structures, etc.) and organic waste that is difficult to separate from this inorganic waste. Things (paper, polyethylene,
Paint, lubricating oil, rubber, etc.).

[0003] By the way, when disposing solid waste, it is said that if the organic matter is removed from the solid waste, radioactive substances in the solid waste are less likely to be dissolved in groundwater, thereby improving the safety of disposal. I have. Therefore, before disposal,
It is important to remove organic matter from solid waste.

[0004] At this time, there is a method of mechanically separating and removing organic substances in solid waste. However, in order to completely remove organic substances, it is absolutely necessary to rely on human labor. It is not practical when handling dangerous materials such as In addition, solid waste, as described above, inorganic and organic substances are mixed in a state that is difficult to separate, and the types and forms of inorganic and organic substances are various,
It is not suitable for remote operation or mechanical separation by an automatic device. Therefore, in order to completely remove the organic matter from the solid waste, it is inevitable to heat the solid waste to thermally decompose the organic matter. Incidentally, in the present invention, this processing is referred to as calcination processing.

As is well known, a rotary grate furnace, a fluidized bed incinerator and the like are usually used for incineration of a large amount of solid waste such as municipal solid waste and general industrial waste. Also, in the field of radioactive solid waste, an incineration melting apparatus for incinerating radioactive solid waste and melting and solidifying the incinerated ash as it is with the same apparatus has been proposed in, for example, Japanese Patent Application Laid-Open No. 6-273519.

[0006]

However, the solid waste to which the present invention is directed is greatly different from ordinary municipal solid waste, general industrial waste, or other radioactive solid waste, and is inflammable. The amount of non-flammable inorganic substances is overwhelmingly larger than the amount of organic substances, and is a so-called non-flammable waste. In addition, the amount of flammable organic matter to be treated varies widely, and the amount of flammable organic matter is not constant. Will fluctuate.

[0007] In the case of general incinerators such as the above-mentioned grate furnace and fluidized bed incinerator used for incineration of flammable organic wastes, combustion air is usually supplied by a blower and controlled. In addition, since the equipment is simple and inexpensive, the supply air amount is usually not fixed but fixed. However, even if the supply air amount is constant, the amount of waste (combustible organic matter)
And the amount of flue gas have a clear correspondence,
During operation of the furnace, a stable combustion state can be obtained by controlling (controlling) only the amount of waste to be injected into the furnace.

On the other hand, when the solid wastes targeted by the present invention are treated in these furnaces, the amount of combustible organic matter is small and the amount of organic matter fluctuates greatly, so that the combustion air is kept constant. Even if the amount of waste input is adjusted in the state,
Inability to control the amount of flue gas and dust generated. That is, control of a constant air supply amount, such as the combustion of combustible waste, causes incomplete combustion and easily generates harmful exhaust gas.Moreover, a large amount of unburned gas and dust causes There is also the danger of excessive internal pressure and fire explosion.

Therefore, in order to prevent the danger of incomplete combustion, it is absolutely necessary to design and operate on the side of excess air, which increases the amount of supplied air. As a result, the amount of exhaust gas increases, and the amount of exhaust gas increases. The processing equipment also becomes large, causing an increase in equipment cost.

Further, in the case of the incineration melting apparatus for radioactive solid waste, the basic apparatus structure is such that a melting vessel is arranged in a furnace main body, and induction heating is performed from outside the furnace to dispose the radioactive solid waste in the melting vessel. The material is incinerated and ashes are melted. Therefore, the heating and cooling of radioactive solid waste is slowed down due to the indirect heating method in which the conductive melting vessel is heated once and the waste is heated by its heat retention and heat storage action, resulting in unstable operation. In addition, it is difficult to perform control such as rapid heating stop corresponding to unsafety. Also, of course,
As in the case of the general incinerator, there is also a problem of operating on the excess air side.

As a result, it is very difficult to treat radioactive solid waste as the object of the present invention in these conventional treatment furnaces, and there is no example of such treatment. Therefore, as a practical matter, the solid waste targeted by the present invention is separated from the flammable waste before the incineration of the flammable waste and stored as untreated, or as described above. It is the present situation that the organic matter is mechanically separated by an emergency and then subjected to a melting treatment or the like.

In view of such circumstances, the present invention provides stable and safe operation even if the waste to be treated is a radioactive solid waste containing a small amount of flammable organic substances and a mixture of inorganic substances and organic substances. It is an object of the present invention to provide a calcining treatment method and apparatus to be used.

[0013]

Means of the present invention for this purpose are a calcining treatment method for heating a radioactive solid waste in which an inorganic substance and an organic substance are mixed and thermally decomposing the organic substance in the waste. During the heating of the radioactive solid waste, the temperature of the radioactive solid waste is measured, and based on the measured value, the amount of heating of the radioactive solid waste is controlled, and the atmosphere around the radioactive waste is cooled to reduce the temperature of the radioactive solid waste. The purpose is to suppress the rate of temperature rise.

A more preferred embodiment of the method of the present invention is to measure the oxygen concentration in the generated exhaust gas during the calcination treatment and to control the amount of heating of the waste according to the change in the oxygen concentration. . Further, another more preferred embodiment of the method of the present invention comprises:
The concentration of carbon dioxide in the generated exhaust gas is also measured, and the end of the calcination treatment is determined based on the change in the concentration of carbon dioxide.

Further, the means of the apparatus of the present invention comprises a heating chamber for heating a radioactive solid waste in which an inorganic substance and an organic substance are mixed, and thermally decomposing the organic substance in the waste, and discharging the generated pyrolysis gas from the heating chamber. An exhaust port, means for supplying air into the heating chamber, means for heating radioactive solid waste in the heating chamber or air supplied to the heating chamber outside the heating chamber, and heating the radioactive solid waste into the heating chamber. The heating chamber of the calcining apparatus comprises a water cooling jacket and a temperature measuring device for the waste in the heating chamber.

A more preferred aspect of the apparatus of the present invention is to have a measuring device for measuring the oxygen concentration in the generated pyrolysis gas. Further, another more preferable aspect of the apparatus of the present invention is that the water cooling jacket is provided with a slit and the radioactive solid waste heating means is constituted by a high frequency induction coil.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS It is known to measure the temperature of the waste to be treated, and the temperature of the waste is also measured by the melting treatment apparatus described in Japanese Patent Application Laid-Open No. 6-23591.
However, a conventional incinerator or the method disclosed in JP-A-6-273
The purpose of measuring waste temperature, such as that of No. 591, is
In order to increase the incineration efficiency of wastes, that is, to keep the temperature high. Conventionally, in order to increase the incineration efficiency of the wastes, the wastes are put into a furnace in which the pyrolysis temperature is kept high in advance. That is common sense.

On the other hand, as described above, the amount of flammable organic matter in the waste subject to the present invention is not constant, and the amount of flammable organic matter introduced into the furnace (heating chamber) is large. Fluctuating, when excess organic matter is injected, the temperature rise rate of waste increases, and it is easy to cause incomplete combustion based on excessive heating, that is, abnormal generation of combustion exhaust gas and dust,
If left unchecked, there is a risk of explosive decomposition.

Therefore, in the present invention, when heating the waste, it is necessary to suppress the rate of temperature rise of the waste, and therefore, the temperature of the waste is measured to suppress the heating amount of the waste. At the same time, cool the atmosphere around the waste. In terms of equipment, the heating chamber for the waste is constituted by a water cooling jacket, and a temperature measuring device for the waste in the heating chamber is arranged.

According to the present invention, the waste to be treated is put into a heating chamber at a temperature lower than the thermal decomposition of organic substances (room temperature to 100 ° C.) in order to suppress the heating of the waste or to perform gentle heating. It is preferred that the temperature be gradually increased and that no additional waste be charged during heating as in the conventional incinerator.

Further, if the heating of the waste is suppressed as in the present invention, that is, if the temperature of the waste is gradually raised from a low temperature state, the oxygen concentration in the exhaust gas also gradually decreases in a detectable state. Therefore, as will be described later, it is easy to detect a change in the amount of oxygen for determining the necessity of the control, and there is also enough time to perform control to prevent overheating after the detection. The rapid rise in the temperature rise rate of the waste also causes a sharp decrease in the oxygen concentration in the exhaust gas.Therefore, even if an attempt is made to detect the decrease in the oxygen concentration in the exhaust gas, or after the detection, the heating is not stopped. Even if the reduction is attempted, there is a problem that there is not enough time for this control.

Incidentally, if the temperature to be measured does not directly measure the temperature of the waste, but corresponds to this waste temperature,
The temperature may be the atmosphere in a furnace (heating chamber) or the temperature of a furnace body such as a bottom plate for placing waste. In addition, temperature measurement equipment,
A direct contact thermometer such as a thermocouple or a non-contact thermometer such as an infrared radiation thermometer can be used as appropriate.

Next, oxygen in the exhaust gas can be measured,
This is a more preferable means from the viewpoint of achieving the object of suppressing the heating of the waste of the present invention. According to the findings of the present inventors, when radioactive solid waste in which inorganic substances and organic substances are mixed is heated to thermally decompose organic substances in the waste, CO or CO _{2 is used.}
There is a certain correlation between the generation of pyrolysis gas represented by the above and the oxygen concentration in the exhaust gas. That is, when the pyrolysis gas is generated,
As the oxygen supplied to the furnace (heating chamber) is consumed, the oxygen concentration in the exhaust gas decreases. Moreover, the decrease (change) in the oxygen concentration is sufficiently larger than the change in the oxygen concentration during the steady operation of the apparatus, and the manner of change is sharp.
The determination can be made separately from the fluctuation of the oxygen concentration due to other factors. Therefore, if the decrease (change) of the oxygen concentration is detected, it can be used as important information for judging the necessity of controlling the heating amount of the waste.

Of course, it is self-evident that if the oxygen in the incinerator is consumed by combustion, the oxygen in the exhaust gas will generally decrease, and CO and CO ₂ generated by the thermal decomposition of organic matter in the furnace will be obvious.
It is also obvious as a phenomenon that there is a correlation between the amount of pyrolysis gas and the oxygen concentration in the exhaust gas. It is also known to analyze components in exhaust gas from the viewpoint of preventing pollution and improving combustion efficiency, and to change combustion conditions of an incinerator based on the results.

However, a known or suggested method that a change in the amount of oxygen, which is a specific component in exhaust gas, can be used in real time and directly as a factor for controlling heating of waste during calcination. There is no example. According to the findings of the present inventors, when pyrolyzing organic matter in waste, the decrease (change) in the oxygen concentration in the exhaust gas due to the generation of pyrolysis gas is caused by the fluctuation in the oxygen concentration during steady operation of the apparatus. Larger and sharper, and can be distinguished from fluctuations in oxygen concentration due to other factors. Therefore,
If this decrease (change) in the oxygen concentration is detected, it can be used as important information for judging the necessity of controlling the heating amount of the waste.

FIG. 1 shows the aging of main components of an exhaust gas when a waste in which an inorganic substance and an organic substance are mixed is heated to thermally decompose the organic substance in the waste to generate a pyrolysis gas (exhaust gas). Indicates a change. Fig. 1 shows simulated waste containing 232 g of iron and zinc as inorganic substances and rubber as organic substance. This waste was heated at 950 ° C in a high frequency induction furnace to generate oxygen, CO, CO _2, etc. It is the result of having measured the quantitative change with time of the exhaust gas component by gas chromatography analysis. In the figure, the thick solid line indicates the exhaust gas temperature, the two-dot chain line indicates the oxygen concentration, the thin solid line indicates the C0 concentration, and the dotted line indicates the CO ₂ concentration. As is clear from the figure, for example, at about 300 ° C. after 5 minutes from the heating of the waste, thermal decomposition of rubber, which is an organic substance, occurs, generating a pyrolysis gas and generating CO or C in the exhaust gas.
O ₂ is increasing. Then, corresponding to this, A in FIG.
As can be seen, a sharp decrease in the oxygen concentration in the exhaust gas has occurred.

The decrease (change) in the oxygen concentration caused by the increase in CO and CO ₂ in the exhaust gas is a phenomenon that occurs in a temperature range of 300 to 800 ° C. at which organic matter is thermally decomposed. As can be seen from the points A and B in FIG. 1, the fluctuations in the oxygen concentration in other parts, such as during the steady operation of the apparatus, are larger and sharper than the fluctuations in the oxygen concentration due to other factors. It is possible to judge. Therefore, the decrease (change) in the oxygen concentration at points A and B in FIG. 1 is captured, and when the decrease in the oxygen concentration is sharp, for example, at point A, the amount of induction heating by the induction coil is suppressed to reduce waste The amount of heat generated is controlled to suppress the generation of pyrolysis gas and prevent incomplete combustion.

By the way, in FIG. 1, not only oxygen but also CO and CO ₂ are greatly and sharply changed (increased) in correlation with oxygen, and instead of oxygen, CO and CO ₂ are heated by waste. It is theoretically possible to use the information to determine the necessity of the quantity control. However, CO and CO ₂ have a smaller absolute amount than oxygen and are hard to detect particularly in the early stage of operation when the amount of generated exhaust gas is small, and a detection error easily occurs. Further, compared to the sharpness of the change in the oxygen concentration, the change in the concentration is slow, and there is a high possibility that the control will be delayed, which is not as practical as oxygen.

It is preferable that the determination of the end of the heating of the radioactive solid waste, in other words, the end of the calcining step be made based on a change in the concentration of carbon dioxide in the generated exhaust gas. According to the findings of the present inventors, as indicated by the point C of the carbon dioxide concentration in FIG. 1, while the pyrolysis of the radioactive solid waste is completed and the pyrolysis gas component is reduced, of the gas components, What returns to the steady state is the carbon dioxide gas. Therefore, the C
The end of the calcining step can be determined by detecting a decrease in the concentration of carbon dioxide as indicated by a dot. Since it is difficult to confirm the radioactive solid waste by directly contacting the treated material, it is preferable to determine the termination based on the decrease in the carbon dioxide gas concentration because the result can be determined without contact.

Next, a specific embodiment of the present invention will be described with reference to FIG. FIG. 2 is an explanatory view showing a calcining apparatus according to the present invention. In the figure, a heating chamber (furnace) main body includes a water cooling jacket 1 and an induction coil 2 for inductively heating waste A in the water cooling jacket. Also,
The calcining air is supplied from a supply port 3 connected to a lower portion of the water cooling jacket 1 by a blower or the like.

Water cooling jacket 1 constituting heating chamber (furnace)
FIG. 3 shows an example. As shown in the figure, the water-cooled jacket
A large number of slits 14 are provided in the circumferential direction of the jacket of the cylindrical structure so that the electromagnetic field generated by the induction coil 2 can effectively penetrate the waste X. A cooling water passage 20 is provided inside the wall surface of the water cooling jacket 1,
The cooling water supplied from the inlet 10 is supplied to the cooling water passage 20.
Circulates through the inside of the water-cooled jacket, cools the water-cooled jacket, and is discharged from the outlet 9.

In order to suppress the heating of the waste and quickly control the amount of heating, it is necessary to provide a heating chamber capable of cooling the furnace wall, such as the water cooling jacket of the present invention. By using a water-cooled jacket for the heating chamber, it is possible to lower the ambient temperature and to safely suppress and heat the waste.

When heat is accumulated in the entire heating chamber as in the prior art, excessive thermal decomposition is detected, and even if an operation for stopping heating is performed, the temperature in the heating chamber cannot be rapidly lowered, and excessive heating cannot be performed. This causes problems such as combustion. For example, the structure of the conventional radioactive solid waste incineration melting apparatus described above heats the conductive melting vessel once, and its heat retention and heat storage action enables
Because of the indirect heating method of heating the waste, the rate of heating and cooling of the radioactive solid waste is slow, and it is difficult to control such as quick stop of the heating corresponding to the instability or unsafeness of the incineration operation.

Water cooling jacket 1 constituting the inner surface of the heating chamber
The bottom plate 4 is preferably made of a material having a high thermal conductivity and being hardly corroded by an acidic gas such as HCl in exhaust gas, and is preferably a nickel-based alloy, a chromium-based alloy, Inconel,
Alternatively, copper or the like coated with a thin ceramic layer can be used.

In FIG. 1, waste X to be treated is supplied from a waste input port 6 into a heating chamber by gravity or a conveyor or the like, and after calcination, a bottom plate 4 for placing waste is removed.
It is lowered by a pulling rod 5 driven by a motor or the like,
From the discharge port 7, it is discharged out of the system by gravity or a conveyor. Since the bottom plate 4 and the drawing bar 5 also become hot due to the operation of the apparatus, the cooling water flows through the inside of the drawing bar for cooling them. In order to continuously process waste, it is reasonable to provide a waste inlet above the heating chamber and discharge waste from below the heating chamber, as in this embodiment. For example, the bottom plate 4 may also be used for loading and unloading waste without providing a waste inlet above the heating chamber.

An exhaust gas sampler 15 is provided at an exhaust gas outlet 8 provided at an upper portion of the heating chamber.
The oxygen concentration meter 11 and the carbon dioxide concentration meter 1
2 is connected to continuously measure the oxygen concentration and the carbon dioxide gas concentration in the exhaust gas. In FIG. 2, the exhaust gas outlet 8
An exhaust gas sampler is provided at the top of the heating chamber. However, in an actual apparatus, a cooling device for exhaust gas having a high temperature and a lot of dust and a dust collecting device are necessarily provided downstream of the exhaust port 8, so that the sampler is used. Considering the measurement accuracy and maintenance issues of
It is preferable to provide it downstream of the cooling dust collector.

Further, a thermocouple or a resistance thermometer 1 is provided on the bottom plate 4.
6 is connected to a waste temperature (furnace temperature) measuring device 13. In the present invention, the heating is suppressed by the temperature measuring device 13 while monitoring the temperature of the waste X in the water-cooling jacket, particularly at the time of starting heating or heating operation.

A treatment operation for heating a radioactive solid waste in which an inorganic substance and an organic substance are mixed using the above-described calcining apparatus and thermally decomposing the organic substance in the waste will be described. First, at the start of heating, while monitoring the temperature of the waste X in the water cooling jacket with the waste temperature (furnace temperature) measuring device 13, the waste is induction-heated by the induction coil 2 and the waste is gently heated. Raise the temperature. And, in the exhaust gas (pyrolyzed gas) generated by thermal decomposition of organic matter in waste,
The concentrations of oxygen and carbon dioxide are monitored by the measuring device 11 and the measuring device 12 via the sampler 15, respectively.

If it is determined that the concentration of oxygen in the exhaust gas is abnormally low and the amount of dust and combustion exhaust gas is large and incomplete combustion occurs, as shown at points A and B in FIG.
Operate the induction coil to stop or reduce the heating of the waste. Regarding the operation of the induction coil due to the change in the oxygen concentration in the exhaust gas, the relationship between the decrease rate of the oxygen concentration and the amount of generated dust and combustion exhaust gas, or the amount of generated dust and combustion exhaust gas, in order to increase the safety and efficiency of operation. It is desirable that the relationship with the timing at which incomplete combustion actually occurs be confirmed in advance by experiments or the like.

After the organic matter in the waste is thermally decomposed as described above, the concentration of carbon dioxide in the exhaust gas monitored by the measuring device 12 is changed from the fluctuating state to the steady state as shown at point C in FIG. At the time when the state is lowered, it is determined that the calcining process is completed, and the heating of the waste is ended. After the calcination process,
As described above, the waste is discharged from the discharge port 7 by lowering the bottom plate 4 with the pull-out bar 5.

When the inorganic material of the radioactive solid waste is mainly a metal, it is preferable to use an induction coil as in this embodiment. The induction coil generates Joule heat in the metal and heats the metal, so that the heating power of the waste can be easily adjusted by adjusting the current of the induction coil. In addition, since the heating can be controlled by remote control, it is suitable for treating radioactive solid waste.

On the other hand, when the inorganic material of the radioactive solid waste is mainly ceramic, it is preferable to use a burner or a resistance heating element. The burner and resistance heating element indirectly heat the atmosphere air in the furnace and heat the waste with this high-temperature air. it can. Further, in order to cope with the difference in the type of inorganic substance of the radioactive solid waste supplied to the apparatus, or to cope with waste in which metal and ceramic are mixed, an induction coil and a burner are used as heating means for the waste. Or a device having a resistance heating element.

FIG. 4 shows an example using the burner and the resistance heating element. This figure is basically the same in structure as the calcining apparatus of FIG. 1, but means for supplying high-temperature air for heating radioactive solid waste into a water-cooled jacket instead of the induction coil of FIG. Is provided. The means for supplying the high-temperature air for heating includes an air intake 18 for taking in air for heating from the atmosphere, a preheating chamber 16 for heating the air to a high temperature by a burner 19, and a supply port 17 for supplying high-temperature air to the heating chamber. Become.

There is no restriction on the basic structure and type of the furnace (heating chamber) as long as the type of the furnace used in the calcining apparatus of the present invention satisfies the configuration of the present invention. It is possible to modify and use a rotary melting furnace or an incineration melting furnace for further melting incineration ash.

[0045]

As described above, according to the calcining method and the calcining apparatus of the present invention, the waste to be treated is a radioactive solid waste containing a small amount of flammable organic substances and a mixture of inorganic substances and organic substances. Even so, stable and safe operation can be obtained. Therefore, it opens the way for waste disposal, which had to be neglected in the past, and made it possible without significantly changing conventional incinerators and incineration melting furnaces. The industrial value in is large.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a change over time of a combustion exhaust gas component.

FIG. 2 is an explanatory sectional view of a calcining apparatus showing an embodiment of the present invention.

FIG. 3 is an explanatory cross-sectional view of a heating chamber of a calcining apparatus, showing an embodiment of the present invention.

FIG. 4 is an explanatory sectional view of a calcining apparatus showing another embodiment of the present invention.

[Explanation of symbols]

 X: Waste 1: Water cooling jacket 2: Induction coil 3: Air supply port 4: Bottom panel 5: Pull-out rod 6: Waste input port 7: Waste discharge port 8: Exhaust port 9: Cooling water outlet 10: Cooling water inlet 11: Oxygen concentration detector 12: Carbon gas concentration detector 13: Waste temperature detector 14: Slit 15: Sampler 16: Preheating chamber 17: Heated air supply port 18: Air intake 19: Burner 20: Cooling water passage

Claims (6)

[Claims] In a calcining treatment method for heating a radioactive solid waste in which an inorganic substance and an organic substance are mixed and thermally decomposing an organic substance in the waste, the temperature of the radioactive solid waste is reduced when the radioactive solid waste is heated. Measuring and controlling the amount of heating to the waste based on the measured value, cooling the atmosphere around the waste, and suppressing the rate of temperature rise of the waste, the radioactive solid waste Calcining treatment method. 2. The method according to claim 1, wherein during the calcination treatment, the amount of heating of the waste is controlled in accordance with the change in the oxygen concentration while measuring the oxygen concentration in the exhaust gas generated by the thermal decomposition of the organic matter. A calcining method for the radioactive solid waste described in the above. 3. The calcination treatment according to claim 1, wherein the concentration of carbon dioxide in the exhaust gas generated by the thermal decomposition of organic substances is measured during the calcination, and the end of the calcination is determined based on the change in the concentration of carbon dioxide. Method for calcination of radioactive solid waste. 4. A heating chamber for heating a radioactive solid waste in which an inorganic substance and an organic substance are mixed and thermally decomposing organic substances in the waste, an exhaust port for discharging generated pyrolysis gas from the heating chamber, and a heating chamber. Means for supplying air, means for heating radioactive solid waste in the heating chamber or air supplied to the heating chamber outside the heating chamber, and loading and discharging the radioactive solid waste into and out of the heating chamber. A calcination treatment apparatus for a radioactive solid waste, characterized in that the heating chamber is constituted by a water-cooled jacket and has a temperature measuring device for the waste in the heating chamber. 5. The apparatus for calcination of radioactive solid waste according to claim 4, further comprising a measuring device for measuring the oxygen concentration in the generated pyrolysis gas. 6. The radioactive solid waste calcining apparatus according to claim 4, wherein a slit is provided in the water-cooled jacket, and the radioactive solid waste heating means comprises a high-frequency induction coil.