JPH02263200A - Pretreating device for radioactive waste - Google Patents

Abstract

PURPOSE:To simplify construction by providing a pressure reducing means which reduces the pressure in a treating chamber, a heat exchanger which condenses an evaporating gaseous component, a recovering means which bisects the component to a condenses liquid and a discharge gas and recovers the same, and a control means which controls the pressure. CONSTITUTION:Drying of waste to be treated is executed in the treating chamber 1 and the evaporating material component from the waste to be treated is introduced through a piping 5 into the heat exchanger 6. The cooling water cooled by a refrigerant pipe 10 of a refrigerator 9 which is operated by a controller 17 is run to the heat exchanger 6 and, therefore, the evaporating gaseous component introduced from the piping 5 releases the heat of condensation and is liquefied to the condensed water which is gathered in the bottom of a condensing tank 7. The condensed water contg., for example, tritiuim gathered in the bottom of the condensing tank 7 is discharged from a conduit 13.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a radioactive waste treatment device, and particularly to a pretreatment device for radioactive waste such as laboratory animals contaminated with radioactive isotopes.

(Prior Art) Radioactive waste is required to be handed over to a designated processing organization stipulated by law. In this case, radioactive waste contaminated with radioactive isotopes, such as laboratory animals, must be heated and dried using a microwave oven or vacuum freeze-drying before being delivered to a designated processing facility.

(Problem to be Solved by the Invention) In the conventional heating drying process using the microwave oven method described above, the waste to be treated, such as laboratory animals, is free from even the slightest amount of metal objects such as scalpels and clips used during experiments. Since it is necessary to perform the heating and drying process after confirming that this is the case, the pretreatment work becomes complicated.

In this case, for example, if the heating and drying treatment is performed while overlooking the presence of even a trace amount of metal remaining in the body of the experimental animal, the metal parts will become abnormally high temperature and ignite.

In addition, for example, if the experimental animal is contaminated with body hair, feces, or feed, heating and drying may not be performed uniformly, and in some cases, some parts may catch fire, or the feces may become
It is difficult to heat and dry blood etc. in a container.

On the other hand, when performing drying treatment by vacuum freeze-drying, the drying time required for a laboratory animal of about 2 kg, for example, takes a long time, 2 to 4 weeks, and the degree of dryness is only about 60% by weight. It cannot be raised. If the degree of dryness is low, the waste will rot during long-term storage and may cause radioactive contamination of the storage area.

The present invention was made in view of the current state of treatment of this type of radioactive waste as described above, and its purpose is to treat waste that is mixed with metal pieces or that is uneven overall. Even if it is in a container containing feces or blood, it can be dried in a short period of time, does not require pre-treatment of the waste, and has a simple structure. An object of the present invention is to provide a waste pretreatment device.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a processing chamber to which a far-infrared heater is attached and for drying radioactive waste, a depressurizing means for reducing the pressure inside the processing chamber, and a processing chamber for drying radioactive waste. a heat exchanger for condensing evaporated gaseous components from the radioactive waste to be dried; and a recovery means attached to the heat exchanger for recovering the evaporated gaseous components by dividing them into condensed liquid and exhaust gas. and a control means for controlling the temperature and pressure of the processing chamber.Furthermore, a weight sensor is built into the processing chamber to detect the degree of dryness of the material to be processed, and the degree of dryness can be inputted in weight percentage. A predetermined dry state can be obtained by keeping the drying condition dry, and deodorizing agent is injected into the exhaust odor treatment device installed at the exhaust port and the treatment chamber to remove the odor generated during drying.
The structure includes a device to reduce odor when the door is opened.

(Function) In the present invention, the waste to be treated, such as a laboratory animal, stored in the treatment chamber is heated by a far-infrared heater attached to the treatment chamber, and the pressure in the treatment chamber is reduced by a pressure reduction means. The means is controlled to a predetermined value by a control means, and the waste to be treated is dried uniformly.

Then, in the processing chamber whose pressure is reduced to a predetermined value by the control means, the evaporated gas components from the waste to be treated are led to a heat exchanger, where most of the evaporated gas components are condensed and become condensed water. It collects in the condensation tank. A recovery means is attached to the heat exchanger, and the evaporated gas component from the waste to be treated is recovered by the recovery means in parts into condensed water obtained in the heat exchanger and exhaust gas.

(Example) Hereinafter, with reference to explanatory diagrams showing the configuration of an example of the present invention,
An example will be explained.

As shown in the figure, in the embodiment, in a processing chamber 1 formed of a heat insulating material and having a substantially square cylindrical shape, a grid plate 2 on which wastes to be processed such as laboratory animals are placed is placed. It is possible to install by changing the position depending on the size of the object,
A far-infrared heater 3 is attached to the upper surface of the inner wall of the processing chamber 1 .

Further, a temperature sensor 4 for detecting the temperature inside the processing chamber 1 is attached to the processing chamber 1, and a piping 5 is installed so as to penetrate the top surface of the inner wall of the processing chamber 1 and open into the processing chamber 1 at one end.
is fixed in the processing chamber 1. The other end of this pipe 5 is
Introduced into the condensation tank 7 via the heat exchanger 6 and opened,
A moisture sensor 8 is attached to a portion of the piping 5 located between the processing chamber 1 and the condensation tank 7.

A refrigerant pipe 10 through which the refrigerant of the refrigerator 9 flows is connected to the heat exchanger 6, and a pipe 11 through which cooling water flows is connected, and the cooling water is circulated to the heat exchanger 6 by a pump 12.

On the other hand, the bottom G of the condensation tank 7 is a conduit 13 for draining condensed water.
An exhaust pipe 14 is led out from the upper surface of the heat exchanger 6, and a pump 15 is inserted into the exhaust pipe 14.

The far-infrared heater 3, temperature sensor 4, moisture sensor 7, cooling temperature sensor 16, and pump 12.15 are each connected to the control device 17 by signal lines. A weight sensor 18 inside the processing chamber 1 is located at the bottom of the grid plate 2 on which the waste to be processed is placed, and detects the weight of the waste to be processed and the grid plate, and a pre-programmed control device controls only the weight of the waste to be processed. Calculate. Then, when the degree of dryness is input in weight percent from the weight, the drying process is completed by the control device. Mana 19 is an exhaust odor treatment device,
It has a structure in which a filter and deodorant can be set inside, and can be replaced as needed! It is made of M. Further, 20 is a device for injecting a deodorant into the processing chamber.

Next, the operation of the embodiment will be explained.

Waste to be treated, for example, an animal used in an experiment using radioactive isotopes and contaminated with radioactive isotopes, is placed in the processing chamber 1, and a sealing lid (not shown) is closed to seal the processing chamber 1. shall be.

The heating temperature of the far infrared heater 3 is set to 1 by the control device 17.
The temperature is heated to 00° C. to 130° C., and the pump 15 is operated so that the inside of the processing chamber 1 is in a vacuum or reduced pressure state. The temperature sensor 4 monitors the temperature inside the processing chamber 1,
A monitoring signal is input to the control device 17, and the far-infrared heater 3
ON-OFF control is performed by the control device 17 so that the heating temperature is 100'C to 130C.

In this way, the waste to be treated is dried in the treatment chamber, and the evaporated gas components from the waste to be treated are guided into the heat exchanger 6 through the pipe 5. Since the cooling water cooled by the refrigerant pipe 10 by the refrigerator 9 operated by the control device 17 is flowed into the heat exchanger 6, the evaporated gas component introduced from the pipe 5 releases the heat of condensation and is liquefied into condensed water. , are collected at the bottom of the condensation tank 7.

A condensate basin, for example containing tritium, collected at the bottom of the condensation tank 7 is discharged via conduit 13.

On the other hand, the evaporated gas components that are not liquefied due to heat exchange with the cooling water in the pipe 11 in the heat exchanger 6 are led to the exhaust pipe 14 and passed through a gas purifying device (not shown) to have a concentration below the maximum allowable concentration of R1. After this is confirmed, it is discharged from a predetermined discharge port.

When the weight of the waste to be processed in the processing chamber 1 is reduced, the weight sensor 8 is activated and the power to the heating heater 3 is turned off. At this time, the pressure reducing device 15 continues to operate, and the power is not turned off at the same time as the heater. The decompression device performs a cooling operation until the object to be treated reaches room temperature and then stops. Thereafter, it is confirmed that the product is in a predetermined dry state, and then handed over to a predetermined processing facility.

According to the embodiment, since the waste to be treated is dried with far infrared rays, uniform drying is carried out in a short time due to the high transmission characteristics of far infrared rays. Moreover, even if metal pieces or non-uniform substances are mixed into the waste to be treated, the drying process can be carried out without any problem.

Furthermore, the drying process can be performed simply and quickly without the need for pre-freezing treatment in the case of vacuum freeze-drying, setting of a heating program in the case of a microwave oven method, or removal of metal pieces from the waste to be treated. In addition, in this device, a weight sensor is used instead of a moisture sensor as a means of determining the degree of dryness, which eliminates the possibility of erroneous stoppage of the device, resulting in a highly reliable drying device.

If the waste to be treated is large, an apparatus with the same performance can be easily obtained by simply enlarging the processing chamber 1 and increasing the capacities of the far-infrared heater 3 and refrigerator 9.

(Effects of the Invention) As explained in detail above, according to the present invention, even if the waste to be treated contains metal pieces or is in a non-uniform state, it can be uniformly dried in a short time using far infrared rays with high transmission characteristics. was carried out,
The evaporated gas components from the waste to be treated are separated into condensed water and non-condensed exhaust gas and recovered, preventing radioactive materials from scattering into the atmosphere or flowing into the ground, making radioactive waste treatment safe. It will be held on.

[Brief explanation of drawings]

The figure is an explanatory diagram showing the configuration of an embodiment of the present invention. 1... Processing chamber, 3... Far infrared heater, 4... Temperature sensor, 5... Piping, 6... Heat exchanger, 7...
Condensation tank, 9... Refrigerator, 10... Refrigerant pipe, 11...
・Piping, 14...Exhaust pipe, 15...Pump, 17.
...Control device, 18... Weight sensor, 19... Exhaust odor treatment device. Patent Applicant: Zhang Fujii Half-time Kuwawa Trading Co., Ltd. Shoji Sou Seisakusho Co., Ltd.

Claims (2)

[Claims] (1) A processing chamber equipped with a far-infrared heater to dry radioactive waste, a depressurizing means for reducing the pressure in this processing chamber, and condensing the evaporated gas components from the radioactive waste to be dried in the processing chamber. A heat exchanger, a recovery means attached to the heat exchanger that divides the evaporated gas component into a condensed liquid and a discharged gas and recovers the same, and a control means that controls the temperature and pressure of the processing chamber. A radioactive waste pretreatment device characterized by: (2) A processing chamber equipped with a far-infrared heater to dry the radioactive waste, a decompression means for reducing the pressure inside the processing chamber, and a weight sensor that detects the dry state of the radioactive waste to be dried in the processing chamber. , a deodorizing device for odor generated during drying, a heat exchanger for condensing the evaporated gas component from the radioactive waste, and a heat exchanger attached to the heat exchanger to divide the evaporated gas component into a condensed liquid and an exhaust gas What is claimed is: 1. A pretreatment apparatus for radioactive waste, comprising: recovery means for recovering condensed liquid through a process chamber; and control means for controlling the temperature, pressure, and drying state of the processing chamber.