KR101585455B1 - Treatment equipment of radioactive liquid wastes - Google Patents

Abstract

The present invention relates to a treatment apparatus for liquid radioactive wastes from a nuclear power plant, and more specifically, to an evaporation-drying treatment apparatus for liquid radioactive wastes having a compact design for evaporating wastewater and drying residues, thereby being appropriate as a mobile treatment apparatus and allowing treatment performance enhancement, life extension, simplification for repair and maintenance, and minimization of radiation exposure. The treatment apparatus for liquid radioactive wastes generated in the nuclear power plant comprises: an evaporation dryer (10) provided with band heaters (10a,10b,10c,10d) built in a containment frame (2) installed in a support frame (1); a hygroscopic moisture separator (20) and a wastewater supply tank (30) having a band heater (20a) connected to the evaporation dryer (10); a regenerative heat exchanger (40) connected to the hygroscopic moisture separator (20) and the wastewater supply tank (30); a condenser (70) provided with an air-cooled type cooler (60) to which the regenerative heat exchanger (40) is connected via a vapor/saturated water discharge pipe (50); a condensate water vacuum tank (80) connected to the condenser (70); and condensate water storage tank (100) connected to the regenerative heat exchanger (40) and the hygroscopic moisture separator (20) via a washing water supply pipe (90) while being connected to the condensate water vacuum tank (80).

Description

[0001] DESCRIPTION [0002] [0002] Treatment equipment of radioactive liquid wastes [

The present invention relates to a liquid radioactive waste disposal apparatus for a nuclear power plant, and more particularly, to a liquid radioactive waste disposal apparatus for a nuclear power plant, and more particularly to a compact radioactive waste disposal apparatus And to an evaporation and drying apparatus for liquid radioactive waste which can minimize radiation exposure.

Typically, the liquid radioactive waste treatment system in a nuclear power plant is composed of a waste liquid evaporator, a concentrated waste liquid drier or a reverse osmosis package and a concentrated waste liquid treatment facility. The concentrated waste liquid drier functions to dry the concentrated waste liquid generated in the waste liquid evaporator to facilitate the disposal, and the concentrated waste liquid treatment facility treats the concentrated waste fluid generated in the reverse osmosis plant in a granular form suitable for the solidification process.

In addition, in some nuclear power plants, a simple evaporator equipped with a separate boiler and steam jacket was operated to treat the special waste liquid generated during operation of the nuclear power plant. The waste liquid evaporator, the concentrated waste liquid drier and the concentrated waste liquid treatment facility all use the auxiliary steam supplied from the power plant as a heating source, and the simple evaporator uses the steam supplied from the separate boiler as a heating source, Highly concentrated to sludge condition.

However, since all of the above evaporation or drying apparatuses use steam as a heat source, a separate steam steam supply facility is required, and evaporation and drying are diverged, so that when the concentrated waste liquid is stored and transported, A separate heating device for preventing solidification is required, so that the structure of the equipment is complicated and it is difficult to design a compact device required for a mobile device, and energy loss due to an indirect heat transfer method using a medium of steam occurs.

In the case of the forced circulation type evaporator, the concentrate in the evaporator circulates through the heat exchanger (heat exchanger), and scales are formed in the heat exchanger tube and the evaporation vessel, which hinders heat transfer, so that maintenance and maintenance such as periodical chemical cleaning and corrosion control are many.

Also, in the case of the decompression evaporator using the mechanical vapor compression (MVR) technique which has been widely used recently, a low temperature evaporation method by decompression is used and no steam or cooling water is required, and it is operated only by supplying electricity necessary for MVR operation. One design is possible, but MVR is relatively expensive to manage and maintain, and the final residue can not be dried in sludge form or solids, thus requiring separate drying for stable storage or disposal.

[Patent Document 1] Korean Patent Publication No. 1991-0009193 (1991. 11. 04) [Patent Document 2] Korean Patent No. 10-0866036 (October 24, 2008)

Accordingly, it is an object of the present invention to solve the above-mentioned problems of the prior art, and it is an object of the present invention to provide an apparatus and a method for manufacturing the same, It is an object of the present invention to provide an apparatus for evaporating and drying liquid radioactive waste which is capable of completely discharging the residue after water drying and improving safety function and maintenance.

According to an aspect of the present invention, there is provided a treatment apparatus for treating liquid radioactive waste generated in a nuclear power plant, the treatment facility comprising an evaporator drier having a band heater mounted in a containment frame installed in a support frame, A regeneration heat exchanger connected to the wet separator and the waste liquid feed water tank, the moisture separator and the waste liquid feed water tank are connected to each other, a condenser having an air cooling type cooler connected to the regeneration heat exchanger through a steam / A condensate water vacuum tank connected to the condenser, and a condensate water reservoir connected to the regeneration heat exchanger and the moisture separator through a cleansing water supply pipe while being connected to the condensate water vacuum tank.

The apparatus for evaporating and drying liquid radioactive waste according to the present invention is characterized in that the evaporation and drying of the liquid radioactive waste is carried out in a single vessel evaporator drier surrounded by an electric band heater, It is suitable as a portable processing device because a compact design is possible since an auxiliary device and a drying device are not required.

In addition, the latent heat of the steam discharged through the regenerative heat exchanger can be recovered, thereby improving the energy utilization rate and the processing performance by 20 to 30%.

In addition, the band heater is installed in multiple stages to prevent overheating of the heater by turning it on / off according to the level of water. By keeping the temperature of heater constant by voltage regulator and preventing surge and inrush current, Extension is possible.

In addition, since it is possible to control the speed, force and direction of rotation of the agitator motor, it is easy to detect and respond to changes in physical properties such as high concentration of waste liquid during evaporative drying operation.

It is also easy to maintain the upper part of the evaporation vessel and the agitator and the internal parts (level and temperature sensor) by providing the lifting air cylinders at the top of the evaporation vessel.

In addition, by adding the scraping function inside the evaporation drying vessel to the agitator, it is possible to improve the heat transfer efficiency and treatment performance by preventing scale formation on the inner wall and bottom of the vessel. In case of processing the radioactive waste liquid, Can be minimized.

Also, since the stirring device has the non-fixed scraper, the scraping function is maintained even if the interval between the inner wall of the container and the scraper is not constant along the entire circumferential direction, and the effect of reducing the production cost required for precision processing of the evaporation drying container have.

In addition, the stirring device is fixed by the lower part of the stirring device drive shaft, and the force is transmitted, thereby ensuring a space for installing the water level sensor and temperature sensing device in the center, thereby accurately measuring, controlling, and monitoring the internal temperature and water level, So that stable operation of the apparatus can be achieved.

In addition, it is possible to prevent contamination of the steam and condensate line due to the Dolby phenomenon, which may occur during the evaporation operation, by providing the condensed water discharge blocking device in the occurrence of the Dolby, And the water quality of the treated water (condensate).

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an overall schematic view showing an evaporative drying treatment apparatus for liquid radioactive waste according to the present invention;
Fig. 2 is an inner plan sectional view of the evaporator dryer,
Figure 3 is a side cross-sectional view of the evaporative drying process,
4 is a partially enlarged cross-sectional view of Fig. 1,
Fig. 5 is a perspective view of the fluid guide tube of Fig. 4,
FIG. 6 is a plan view of the isolation discs in FIG. 4; FIG.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an overall schematic view showing an evaporative drying treatment apparatus for liquid radioactive waste according to the present invention. FIG.

The present invention relates to a treatment apparatus for treating liquid radioactive waste generated in a nuclear power plant as shown in FIG. 1, wherein the treatment facility comprises a band heater (10a) mounted in a containment frame (2) A moisture separator 20 having a band heater 20a connected to the evaporation drier 10; a waste liquid supply water tank 30; and a moisture separator (not shown) And a regenerative heat exchanger 40 connected to the waste liquid supply water tank 30 and an air cooling type cooler 60 connected to the regeneration heat exchanger 40 via a steam / A condensate water vacuum tank 80 connected to the condenser 70 and a clean water supply pipe 90 connected to the condensate water vacuum tank 80 and the regenerated heat exchanger 40 and the moisture separator 20, And a condensed water storage tank 100 connected to the condensed water storage tank 100 through a pipe.

As shown in FIGS. 1 to 3, in the evaporation drier 10, the evaporation and drying of the liquid radioactive waste supplied from the waste liquid supply water tank 30 is performed by the electric band heaters 10a to 10d, The evaporator dryer 10 is surrounded by upper and lower sub-band heaters 10a, 10b, and 10c and a bottom band heater 10d.

Accordingly, the evaporator / dryer 10 can be compactly designed for evaporating the waste liquid and drying residues. The evaporative dryer 10 recovers thermal energy from the discharged steam by applying the regenerative heat exchanger 40 to the evaporator dryer 10 So that the temperature of the waste liquid can be raised near the breaking point.

The band heaters 10a to 10d are installed in the upper and lower portions of the evaporator drier 10 in a multistage manner and are gradually turned off from the upper band heater 10a when the level of the waste liquid is lowered, It is possible to prevent the surge and inrush current and control the set temperature of each band heater to be constant by controlling the minute voltage.

The stirrer 11 of the evaporation drier 10 includes a stirrer motor 12, a rotating shaft 13 connected to the stirrer motor 12 and rotating, an inner wall scraper 14, a bottom scraper 15, And the rotating shaft lower fixed bundle 16 so that the speed and force of the stirrer motor 12 can be controlled and measured.

Therefore, the stirrer 11 operates to enable high speed / low speed and forward rotation / reverse rotation so as to cope with changes in physical properties such as high concentration of waste fluid during operation of the steam drier 10.

The upper portion of the evaporation drier 10 is provided with an evaporation container upper lifting air cylinder 17 and the upper portion of the evaporation drier 10 and the number of the holding portions of the stirrer 11, the water level sensor 18 and the temperature sensor 19 .

2 and 3, the stirrer 11 of the evaporation drier 10 according to the present invention includes a rotary shaft 13 corresponding to a load of an internal fluid or solid material on the side and lower side of the stirrer 11, The scraper 14 and the floor scraper 15 are moved by the scraper 14 and the scraper 15 to periodically remove the solids adhering to the inner wall and the bottom of the evaporator 10 to reduce the heat transfer efficiency And is configured to smoothly discharge the final residue through the final residue outlet (110) with the discharge valve (111).

The stirrer 11 is fixed by only the rotating shaft lower stationary bundle 16 connected to the rotating shaft 13 of the stirrer 11 and the force is transmitted to the center of the evaporator drier 10, So that the installation space of the air conditioner 19 can be ensured.

4 to 6, when the superheated condensate inside the superheated condensate is rapidly expanded and discharged to the steam discharge pipe 121 during the operation of evaporating and drying the liquid radioactive waste in the evaporation drier 10, (122) is pushed up by the inflation pressure and is seated on the blocking disk seating plate (123) to shut off the passage of the steam discharge pipe (120) to block the discharge of the concentrate.

The superheated concentrate shielding device 120 of the evaporation and drying device 10 includes a shielding disc 122, a shielding disc guide rod 127, a shielding disc seating plate 123, a shielding disc guide pipe 124, (125), and a fluid guide tube (126).

In the figure, reference numerals 130a to 130c denote pumps, and 140 denotes a pressure reducing valve.

The apparatus for evaporating and drying liquid radioactive waste according to the present invention having the above-described structure is characterized in that when the liquid waste is treated in a nuclear power plant, evaporation and drying are carried out in the evaporator drier 10, which is a single container in which the electric band heaters 10a- It is possible to manufacture a portable type treatment device capable of compact design in which the waste liquid is evaporated and the residues are dried in the inside of the container. The agitator (11) .

In addition, a shutoff disk 122 for shutting off the discharge of the concentrate when the dolby phenomenon occurs, in which the overheated concentrate is rapidly expanded in the evaporation dryer 10 and is discharged to the steam discharge pipe 121, is installed to prevent contamination of the condensate line And improvement of the processing performance and the safety function.

Further, the evaporation dryer 10 can be lifted by the lifting air cylinder 17 installed on the upper part of the evaporation drier 10, thereby facilitating maintenance.

While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments.

1: support frame, 2: storage frame,
10: Evaporating dryer, 10a to 10d: Band heater,
11: stirrer, 12: motor,
13: rotation shaft, 14: inner wall scraper,
15: floor scraper, 16: rotating shaft lower fixing bundle,
17: lifting air cylinder, 18: water level sensor,
19: Temperature sensor, 20: Moisture separator,
20: waste liquid supply tank, 40: regenerative heat exchanger,
50: steam / saturated water discharge piping, 60: air cooling cooler,
70: condenser, 80: condensate water vacuum tank,
90: rinse water supply pipe, 100: condensed water storage tank,
110: final residue outlet, 120: superheat condensation heat blocker,
121: steam discharge pipe, 122: interrupting disk,
123: interrupter disk seating plate, 124: interrupting disk guide tube,
125: stop disk stopper, 126: fluid guide tube,
127: Blocking disc guide rod.

Claims (7)

An evaporator drier (10) having band heaters (10a, 10b, 10c, 10d) mounted in a containment frame (2) installed in a support frame (1) for treating liquid radioactive waste generated in a nuclear power plant, A regenerating heat exchanger 40 connected to the wet separator 20 and the waste liquid feed water tank 30, a wet separator 20 having a band heater 20a connected to the dryer 10, a waste liquid feed water tank 30, A condenser 70 having an air cooled cooler 60 connected to the regeneration heat exchanger 40 via a steam / saturated water discharge pipe 50, a condensate vacuum tank 80 connected to the condenser 70, And a condensed water storage tank (100) connected to the regeneration heat exchanger (40) and the wet separator (20) through a rinse water supply pipe (90) while being connected to the condensate water vacuum tank (80) In the evaporation drying treatment apparatus,
The stirrer 11 of the evaporation drier 10 includes a stirrer motor 12, a rotating shaft 13 connected to the stirrer motor 12 and rotating, an inner wall scraper 14, a bottom scraper 15, , And a rotary shaft lower fixed bundle (16). delete delete The method according to claim 1,
Wherein the agitator (11) operates so as to be capable of high speed / low speed and forward / reverse rotation. The method according to claim 1,
The upper portion of the evaporation drier 10 and the number of maintenance parts of the agitator 11, the water level sensor 18 and the temperature sensor 19 are provided on the upper side of the evaporation drier 10, Wherein the drying of the liquid radioactive waste is carried out easily. The method according to claim 1,
The inner wall scraper 14 and the floor scraper 15 movable by the rotation axis 13 in correspondence with the loads of the internal fluid or the solid matter are provided on the side and the lower side of the agitator 11, And the solids adhering to the bottom are periodically removed to prevent the reduction of the heat transfer efficiency due to the scale formation inside the container and to smooth the discharge of the final residue through the final residue outlet 110 with the discharge valve 111 Wherein the liquid radioactive waste is a radioactive waste. The method according to claim 1,
The superheated condensate shielding device 120 of the evaporation drier 10 includes a shielding disc 122, a shielding disc guide rod 127, a shielding disc seating plate 123, a shielding disc guide pipe 124, 125), and a fluid guide pipe (126).

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