JPH0713673B2 - Radioactive waste treatment equipment - Google Patents

Description

Description: [Object of the Invention] (Field of Industrial Application) The present invention relates to a radioactive waste treatment apparatus, and more particularly to improvement of a vapor supply / exhaust system of a centrifugal thin film dryer.

(Prior Art) A conventional example will be described with reference to FIG. FIG. 2 is a view showing a configuration of a centrifugal thin film dryer and a steam piping system connected to the centrifugal thin film dryer. In the figure, reference numeral 1 indicates an upper body of the centrifugal thin film dryer.
Below the body upper body 1, a body lower body 2 is separately arranged. An upper steam jacket 3 is integrally installed on the outer periphery of the main body upper body 1 with a predetermined interval,
Further, a lower steam barrel 4 is integrally arranged on the outer periphery of the lower body barrel 2 with a predetermined gap. An upper structure including an upper body upper body 1 and a steam upper jacket 3, and a lower body body 2
The lower structure including the lower steam jacket 4 and the lower steam jacket 4 is joined by a flange (not shown). And an annular space between the upper body 1 of the steam body and the upper jacket 3 of the steam,
The heated steam is supplied to the annular space between the lower body 2 and the lower steam jacket 4. A drive unit 5 is installed above the upper body 1 of the main body, and a shaft 6 is connected to the drive unit 5. A rotating body 6a is installed on the upper end of the shaft 6, and a plurality of scraping blades 7 are fixed below the rotating body 6a. The liquid to be treated is introduced into the upper body 1 and the lower body 2 from above via a treatment liquid supply pipe (not shown). The introduced liquid to be treated is scattered in the radial direction by the rotating rotator 6a and flows down in a thin film form along the inner peripheral surfaces of the main body upper body 1 and the main body lower body 2. At that time, it is dried and the volatile components evaporate,
The non-volatile components adhere to the inner peripheral surfaces of the upper body 1 and the lower body 2 of the main body, are scraped off by the blade 7 and are discharged to the outside.

Next, the structure of the steam supply / discharge pipe system will be described. Heating steam supply pipes 8 and 9 are connected to the upper steam jacket 3 and the lower steam jacket 4, respectively, and these heating steam supply pipes 8 and 9 collectively form a heating steam supply pipe 10.
Has become. A steam pressure adjusting valve 11 is inserted in the heating steam supply pipe 10. A steam return pipe 12 is connected to a lower portion of the steam upper jacket 3, and an opening / closing valve 13, a steam trap 14, and an opening / closing valve 15 are sequentially inserted in the steam return pipe 12. A bypass pipe 17 having a bypass valve 16 is installed in the opening / closing valve 13, the steam trap 14, and the opening / closing valve 15. On the other hand, a steam return pipe 18 is also connected to the lower portion of the steam lower jacket 4, and an opening / closing valve 19, a steam trap 20, and an opening / closing valve 21 are sequentially inserted in the steam return pipe 18. These open / close valve 19, steam trap 20, and open / close valve
A bypass pipe 2 equipped with a bypass valve 22 is attached to the 21.

A pressure oscillator 24 is attached to the heating steam supply pipe 10, and a pressure detection signal S24 from the pressure oscillator 24 is input to a pressure instruction controller 25. Based on this signal S24, the pressure instruction controller 25 outputs a control signal S25 to the pressure adjusting valve 11 to adjust the opening thereof. A temperature detector 26 is attached to the heating steam supply pipe 9, and temperature detectors 27 and 28 are also attached to the steam return pipes 12 and 18, respectively. The temperature detection signals S26, S27, S28 from these temperature detectors 26 to 28 are input to the multipoint recorder 29.

According to the above configuration, the pressure of the steam supplied through the heated steam supply pipe 10 is detected by the pressure oscillator 24, and the detection signal S24 is output to the pressure instruction controller 25. The pressure instruction controller 25 adjusts the opening degree of the pressure adjusting valve 11 based on the detection signal S24. The steam supplied by this is controlled to a predetermined flow rate. The supplied steam is introduced into the steam upper jacket 3 and the steam lower jacket 4 through the heating steam supply pipes 8 and 9, respectively. As a result, the insides of the upper body 1 and the lower body 2 are heated, the introduced liquid is heated and dried, the volatile components are evaporated, and the non-volatile components are the inner peripheral surfaces of the upper body 1 and the lower body 2. Adhere to. On the other hand, the steam flows out in a condensed state through the steam return pipes 12 and 18, and is discharged through the steam traps 14 and 20. The temperature of the supplied steam and the temperature of the flowing steam are respectively detected by the temperature detectors 26 to 28 and recorded in the multipoint recorder 29.

In the above configuration, when the liquid to be treated is condensed waste liquid, heat may be generated in the lower body 2 of the main body. When such a heat generation phenomenon occurs, by opening the bypass valve 22 of the steam return system connected to the lower body 2 of the main body, the uncondensed heated steam is forced to flow, and the steam for heating is discharged. On the contrary, an operation of cooling the lower body 2 of the main body by using it as a coolant is performed. However, when adopting such a method, there are various problems, and particularly, there are three problems described below.

First, since the heated steam is returned to the steam return system via the bypass valve 22 without being completely condensed, it is expected that the pressure balance of the steam return system will be lost.

Compared to normal operation, a large amount of steam is consumed, which is not preferable for reducing operating cost.

Since the bypass valve 22 is opened to bypass the steam trap 20, the steam pressure fluctuates and the steam temperature supplied to the steam upper jacket 3 also fluctuates, resulting in heating / heating.
The properties of the powder produced by drying deteriorate, and coarse particles come to be contained in the powder.

(Problems to be Solved by the Invention) As described above, in the conventional configuration, problems such as collapse of the pressure balance of the vapor return system, increase of the amount of vapor consumed, and generation of coarse particles due to fluctuation of the vapor temperature are generated. However, the present invention has been made on the basis of such a point, and the purpose thereof is to disrupt the pressure balance of the vapor return system, increase the amount of vapor consumed, and fluctuate the vapor temperature to cause coarse particles. An object of the present invention is to provide a radioactive waste treatment device that can effectively suppress the heating of the lower body of the main body without causing a problem such as generation.

[Structure of the Invention] (Means for Solving the Problems) That is, a radioactive waste treatment apparatus according to the present invention comprises a body upper body, a body lower body provided separately below the body upper body, and A steam upper jacket which is arranged on the outer periphery of the upper body and forms a steam heating space with the upper body, and a lower steam which is arranged on the outer periphery of the lower body and forms a steam heating space with the lower body. The jacket and the liquid to be treated supplied from the upper end of the upper body of the main body, which is axially extended in the upper body and the lower body of the body, are scattered by the centrifugal force in the radial direction to separate the upper body and the lower body of the body from each other. A rotating mechanism that flows down in a thin film along the inner peripheral surface and scrapes off the non-volatile components of the liquid to be treated adhering to the inner peripheral surfaces of the upper body and lower body, and heating steam connected to the steam lower jacket. Supply distribution A connecting pipe for connecting the steam lower jacket and the steam upper jacket to introduce the steam supplied into the steam lower jacket through the heating steam supply pipe into the steam upper jacket; and the steam upper jacket and the steam lower part. The steam temperature of the steam return system connected to the jacket and the steam temperature of the steam return system inserted in the steam heating supply pipe and connected to the steam upper jacket. And a regulating valve for holding the valve constant.

(Operation) That is, when the lower body of the main body generates heat, the temperature of the steam flowing out from the upper steam jacket via the steam return system rises. By detecting this temperature rise, the opening of the regulating valve inserted in the heating steam supply pipe is narrowed, and the steam temperature in the steam lower jacket is lowered. The steam having the lowered temperature cools the lower body of the main body in the lower steam jacket, is heated to an appropriate temperature, and is supplied into the upper steam jacket through the connecting pipe. This effectively suppresses the heat generation of the lower body of the main body and maintains the temperature of the steam supplied into the upper steam jacket at an appropriate level.

(Embodiment) An embodiment of the present invention will be described below with reference to FIG. The same parts as those of the prior art are designated by the same reference numerals and the description thereof will be omitted. Reference numeral 101 in the drawing is a heating steam supply pipe, and this heating steam supply pipe 101 is connected to the lower part of the lower steam jacket 4 and a regulating valve 102 is inserted. The lower steam jacket 4 and the upper steam jacket 3
Are connected to each other via a communication pipe 103. Therefore, the steam supplied into the steam lower jacket 4 through the heating steam supply pipe 101 is supplied into the steam upper jacket 3 through the communication pipe 103. In the figure, reference numeral 105 is a temperature transmitter, and this temperature transmitter 105 detects the temperature of the return steam flowing in the steam return pipe 12 of the steam upper jacket 3,
The temperature detection signal S105 is output to the converter 106. Converter 1
06 converts the temperature detection signal S105 into a pressure signal and outputs the signal S1.
It is output to the pressure instruction controller 25 as 06. The pressure instruction controller 25 adjusts the opening degree of the adjusting valve 102 based on the signal S106.

The operation will be described based on the above configuration. The steam supplied from the heating steam supply pipe 101 is first supplied into the steam lower jacket 4. The steam supplied into the steam lower jacket 4 is supplied into the steam upper jacket 3 via the communication pipe 103. As a result, the insides of the upper body 1 and the lower body 2 are heated. In such a heating state, the liquid to be treated supplied into the upper body 1 of the main body from above flows down in the upper body 1 of the main body and the lower body 2 of the main body in the form of a thin film, at which time it is dried to evaporate volatile components. However, the non-volatile components adhere to the inner peripheral surfaces of the upper body 1 and the lower body 2 of the main body. The attached non-volatile components are scraped off by the blade 7 and discharged.

During the above operation, the temperature of the steam flowing out from the steam upper jacket 3 through the steam return pipe 12 is determined by the temperature transmitter 105.
Is detected by the pressure detection controller and input to the converter 106 as a temperature detection signal S105 and further as a signal S106.
Entered in 25. The pressure instruction controller 25 sends the signal S106
Based on the above, the control signal S25 is output to the adjusting valve 102 to adjust its opening degree, whereby the temperature of the steam supplied to the steam upper jacket 3 is kept constant and the powder performance is maintained.

Next, a case where the lower body 2 of the main body is in a heat generating state will be described. In this case, the temperature of the steam flowing out of the steam upper jacket 3 rises. As a result, the pressure indicating controller 25
Outputs a control signal S25 to reduce the opening of the adjusting valve 102.
Then, the flow rate of steam supplied through the heated steam supply pipe 101 is reduced, and the temperature of the steam flowing into the lower steam jacket 4 is lowered. The steam whose temperature has dropped is heated in the lower body 2 of the main body, which is in a heat generating state, to a predetermined temperature, and is supplied into the steam upper jacket 3 through the communication pipe 103. On the other hand, the supply of the low-temperature steam cools the lower body 2 of the main body, which is in a heat generating state, and suppresses the heat generation. In this way, even if the lower body 2 of the main body is in a heat generating state, the upper steam jacket 3
Since the temperature of the steam supplied inside is kept constant, the powder performance is maintained at a predetermined quality. At the same time, since the lower main body 2 in the heat generating state is cooled by the low temperature steam, the heat generation is effectively suppressed.

According to this embodiment, the following effects can be obtained.

First, even if a heat generation occurs in the lower body 2 of the main body,
Since the supply of the steam having the lowered temperature and the flow of the steam to the steam upper jacket 3 are ensured through the communication pipe 103, the heat generation of the lower body 2 of the main body is effectively suppressed.

Further, the steam controlled to a predetermined temperature is supplied into the steam upper jacket 3. Therefore, stable powder generation is continued (powder generation is mainly performed in the upper body 1 of the main body), and coarse particles are not contained in the powder.
By keeping the properties of the powder constant in this way, it becomes possible to maintain a uniform mixed state of the powder even when the plastic individualized products are packed into drums using the powder, and thus individualized Increases the average strength of the body.

Further, the amount of steam consumed is almost constant, a large amount of steam is not consumed as in the conventional case, and the heating steam is not discharged to the steam return system so that the vanins are not destroyed.

Moreover, since the heat generation of the lower body 2 of the main body is effectively suppressed,
There is no temperature difference between the main body upper body 1 and the main body lower body 2, so the thermal expansion and thermal strain of the main body upper body 1 and the main body lower body 2 are equal, and the structural soundness can be effectively maintained.

The present invention is not limited to the above-described one embodiment, and for example, the regulating valve 102 may be controlled not only by the steam temperature but also by the signal S24 from the pressure transmitter 24 in a complex manner.

[Effects of the Invention] As described in detail above, according to the radioactive waste treatment apparatus of the present invention, the steam to be supplied is further increased without increasing the consumption amount of steam and without disturbing the pressure balance of the steam return system. It is possible to effectively suppress the heat generation of the lower body of the main body without changing the temperature. Further, since it is possible to provide the steam having a constant temperature in the steam upper jacket, it is possible to effectively prevent the trouble caused by the stable powder performance and the deterioration of the powder performance.

[Brief description of drawings]

FIG. 1 is a block diagram of a steam piping system around a centrifugal thin film dryer showing an embodiment of the present invention, and FIG. 2 is a block diagram of a steam piping system around a conventional centrifugal thin film dryer. 1 ... Main body, 2 ... Bottom body, 3 ... Steam upper jacket, 4 ... Steam lower jacket, 12,18 ... Steam return pipe, 25 ... Pressure indicating controller, 101 ... Heating steam supply Piping, 102 ... Steam temperature control valve, 103 ... Communication piping, 105 ... Temperature transmitter.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Hideaki Fujimura Inventor Hideaki Fujimura 1-18-17 Nishishimbashi, Minato-ku, Tokyo, Toshiba Engineering Co., Ltd. (56) References JP-A-52-5047 (JP, A) Kai 57-51724 (JP, A)

Claims (1)

[Claims] 1. A steam heating space is formed between a body upper body, a body lower body separately provided below the body upper body, and a body upper body arranged on the outer periphery of the body upper body. A steam upper jacket and a steam lower jacket which is arranged on the outer periphery of the lower body of the main body and forms a steam heating space between the lower body of the main body, and an upper portion of the main body which is axially extended and arranged in the upper and lower body of the main body. The liquid to be treated supplied from the upper end of the body is scattered in the radial direction by centrifugal force to flow down in a thin film along the inner peripheral surfaces of the upper body and the lower body of the main body, and inside the upper and lower body A rotating mechanism for scraping off the non-volatile components of the liquid to be treated adhering to the peripheral surface, a heating steam supply pipe connected to the steam lower jacket, a steam lower jacket and a steam upper jacket are connected, and the heating steam supply arrangement is connected. The connecting pipes for introducing the steam supplied into the lower steam jacket through the upper steam jacket, the steam return systems connected to the upper steam jacket and the lower steam jacket, and the steam heating steam supply pipe. And a regulating valve for adjusting the degree of opening of the steam returning system connected to the steam upper jacket by the steam temperature to keep the temperature of the steam supplied into the steam upper jacket constant. Processing equipment.