JPS61184497A - Volume-reducing treater for waste liquor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a waste liquid volume reduction treatment device for drying and powdering waste liquid and compression molding the powder into a pellet shape. The present invention relates to a waste liquid volume reduction treatment device suitable for obtaining a pellet-like molded body having a predetermined strength and a constant bulk density even when the ratio changes.

[Background of the invention]

Generally, radioactive waste generated from nuclear power plants or other nuclear facilities is classified and treated or stored according to its properties. - For example, sodium sulfate (which is generated in large quantities in boiling water nuclear power plants)
Radioactive liquid waste such as recycled waste liquid of ion exchange resin containing Na, 5o4) as a main component is solidified with cement or asphalt in a 200Q drum. In addition, used ion exchange resins, filter aids, and the like are stored in tanks in the form of slurry, so securing storage space for these radioactive wastes has become a problem. Therefore, attempts have been made to reduce the volume of the radioactive waste by a large amount by drying it into powder using a centrifugal thin film dryer or the like, and then granulating it into pellets using a granulator such as a briquetting machine. There is.

However, radioactive waste to be treated contains various impurities in addition to sodium sulfate, and its composition changes day by day, causing physical property values such as moisture content in the resulting powder to fluctuate. It may be difficult to granulate the product into a pellet-like molded product having a certain bulk density. Therefore, it is necessary to always maintain the operating conditions of the granulation process at an optimum value depending on the water content in the powder.

In addition, as an example related to this type of device,
5080, Japanese Patent Publication No. 58-2638, etc.

[Purpose of the invention]

An object of the present invention is to provide a waste liquid volume reduction treatment device equipped with a means for measuring the water content contained in the generated powdered radioactive waste and a means for calculating and controlling the operating conditions for granulation. It is in.

[Summary of the Invention] A feature of the present invention is that a part of the powder discharged from the dry pulverization process is sampled, the water content in the powder is directly measured, and the granulator is adjusted according to the measured value. The main difference is that it has a function to calculate and control the optimum operating conditions for the system. Therefore, even if the water content in the powder changes, the granulator can always be operated under optimal conditions.

[Embodiments of the invention]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an example in which an embodiment of the present invention is applied to a volume reduction treatment device for waste liquid generated from a nuclear power plant will be described with reference to the drawings.

1 to 3, the volume reduction treatment device is a supply tank 9. A metering pump 8, a centrifugal thin film dryer 1, a powder hopper 2, a granulator 3, a powder sampling device 6 attached to the powder hopper +2, and a control computer that controls the operation of the granulator 3. It consists of 7. The powder sampling device 6 includes a cylinder 61, as shown in FIG.
It is composed of a piston 62 and a sample storage part 63, and is equipped with an infrared moisture meter 5 for measuring the physical property values contained in the sample 41, especially the water content. The configuration of the granulator 3, which is the main machine in the granulation process, will be explained with reference to FIG. The granulator 3
is the granulator hopper 36. A screw feeder 37 having a mechanism for pushing powder 40 downward, and the control computer 7
The variable drive motor 33 rotates the screw feeder 37 according to preset operating conditions, the variable drive motor 32 adjusts the rotatably attached roll 34 to the optimum rotation speed, and the pressurizer pressurizes the roll 38 with the optimum pressure. It consists of a pressure device 31.

The roll 38 is rotatably mounted in synchronization with the roll 34 using a suitable power transmission device (not shown).

Recycled waste liquid, etc. generated from boiling water nuclear power plants, 20
After being concentrated to about wt%, it is supplied into the centrifugal thin film dryer 1 via a supply tank 9 and a metering pump 8. Inside the centrifugal thin film dryer 1, there is a rotating shaft 1 that rotates a movable blade 12.
1 is inserted.

The inner wall surface of the body of the centrifugal thin film dryer 1 is covered with a heating jacket 13.
heated indirectly by heating steam through the

As the rotating shaft 11 rotates and the movable blade 12 acts,
The treated waste liquid supplied into the centrifugal thin film dryer 1 is pressed against the heated inner wall surface of the body in the form of a thin film.

The water in the treated waste liquid evaporates as it flows down along the inner wall surface of the body, and the solid content in the treated waste liquid is precipitated. 1. This solid content is pulverized by the rotation of the movable blade 12. The generated powder 40 is discharged from the lower part of the centrifugal thin film dryer 1 to the powder hopper 2.

When a predetermined amount of powder 40 is sent to the powder hopper 2,
As shown in FIG. 2(b), the cylinder 61 and the piston 6
2, the powder 40 is sampled. Subsequently, as shown in FIG. 2(c), the sampled powder 40 is compression molded using the piston 62 to form a sample 41.
After that, the measured value of the moisture content in the sample 41 is input to the operation control computer 7, which is the next step, and the optimum operating conditions for the granulator 3 are set in accordance with established standards.

Although the sample 41 that has been subjected to the 81 g determination is not shown, it is returned to the powder hopper 2 and mixed into the powder 40.

The powder 4o whose moisture content has been measured as shown in FIG. 3 is transferred to the granulator hopper 36.

Next, the variable drive motor 33 is operated under conditions preset by the control computer 7 based on the moisture content measured by the sample 41, and the screw feeder 37 is rotated via an appropriate power transmission device, and the powder is powdered. Body 40 is roll 3
It is pushed into the meshing part of 4.38. At the same time, the pressurizing device 31 pressurizes the roll 38 at the optimal pressure set by the control computer 7, and the variable drive motor 32 adjusts the rotation speed to the optimal rotation speed to operate the roll 34, thereby releasing the powder. 4
The pellets 0 are compression molded into almond-shaped pellets 42 by pockets 35 provided on the surfaces of the rolls 34 and 38. Although not shown, the pellets 42 are filled into a 200M drum or the like and stored.

In the above embodiment, if the measured moisture content of the sample 41 exceeds the granulation standard, the powder 40 is not transferred to the granulation process but is transferred again to the supply tank 9 via an appropriate piping operator. Easy to restart.

It should be noted that the above embodiments are intended to explain the present invention in detail, and are not intended to limit the present invention.

〔Effect of the invention〕

According to the present invention, a part of the powder produced by drying and pulverizing waste boards is sampled and its physical properties are directly measured, and based on this, the control computer sets the optimum operating conditions for the granulator. As a result, stable pellet-like granules that always have a predetermined strength and a constant bulk density can be obtained even if the physical properties of the powder, especially the water content, change due to changes in the composition of the waste liquid to be treated. be able to.

[Brief explanation of the drawing]

Figure 1 is a system diagram of a waste liquid volume reduction treatment device according to an embodiment of the present invention, Figure 2 is a diagram showing powder sampling and measurement of physical property values, and Figure 3 is a detailed diagram of the structure of the granulator. It is a diagram. 6... Powder sampling device, 5... Infrared moisture meter, 41... Sample, 61... Cylinder, 62...
... Piston, 63... Sample storage section, 7... Control computer. 3... Granulator, 31... Pressure device, 32, 33...
・Drive 11 + - Plow - ++ -++ ++ -Part 2 mouths (0L) <C>

Claims (1)

[Claims] 1. A dryer that pulverizes waste liquid, a granulator that granulates the powder produced by the dryer, and a measurement of the water content in the powder before granulation. A waste liquid treatment system comprising: a powder hopper having a means for sampling a part of the powder stored in the lower part of the dryer; and a moisture content measuring means for measuring the moisture content of the sampled powder. 1. A waste liquid volume reduction treatment device, comprising: arithmetic and control means; 2. The calculation control means stores specification data of the granulator, inputs data from the moisture content measuring means, and calculates and controls the operating conditions of the granulator. A waste liquid volume reduction treatment apparatus according to claim 1.