JPS605232A - Centrifugal separator for regenerating powdery ion exchange resin - Google Patents

Abstract

PURPOSE:To achieve the enhancement of safety, the reduction in required power and the enhancement in separation efficiency, by providing mist removing cooling apparatuses to the liquid supply system, the casing and the gas exhaust system of an ion exchange resin regenerating apparatus comprising a rotary barrel rotating at a high speed. CONSTITUTION:A porous cylinder 3 and an inorg. cylinder 5 are rotated in an outer casing 21 by a motor 1 and a drive shaft 2 to separate a powdery ion exchange resin by centrifugal force. Mist removing cooling apparatuses 28, 24 are attached to a resin supply pipe 13 and a washing water supply pipe 8 to cool both of them to a proper temp. by a chiller 26. The inside of the outer casing 21 can be brought to negative pressure by a vacuum pump 27 and a cooler is provided in order to cool air to be exhausted to remove mist of caustic soda and cooled by the chiller 26.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a centrifugal separator for regenerating powdered ion exchange resin, and in particular to a centrifugal separator suitable for improving safety by installing a cooling device. The present invention relates to a centrifugal separator for regenerating ion exchange resin.

[Background of the invention]

FIG. 1 shows a cross section of a conventionally known centrifugal separator for regenerating used powdered ion exchange resin. The centrifuge has 5 non-porous outer cylinders and 3 porous inner cylinders.

4. The drive shaft of the motor 52 in 1 which rotates the end plate in 6, the fixed rod 7, the cleaning pipe 8, the fluid (including solid matter with low specific gravity) discharge pipe 9, and the drive shaft 10. Mechanism, 1
1 is a filtrate discharge pipe, 12 is a drive mechanism thereof, 13 is a supply pipe, 14 is a scraper, 15 is a scraper vertical mechanism, 16 is a scraper horizontal mechanism, and 17 is a solid discharge port. When the centrifugal separator reaches its rated rotation with the motor No. 1, it supplies one separation liquid of the powdered ion exchange resin to be separated from the supply pipe No. 13.
The separated liquid is taken out from the fluid discharge pipe 9, and the heavy powdered cation exchange resin is washed with water from the washing pipe 8 and then scraped off by the scraper 14 when the rotation speed is low. The structure is such that the solids are taken out from the solid discharge port.

The regeneration flow sheet for used ion exchange resin is as shown in FIG. First, solid impurities are removed, and after pretreatment and dehydration, the resin is separated into cationic and anionic resins using the centrifugal separator described above, each of which is dehydrated, regenerated, and reused.

When we attempted to manufacture a full-scale centrifugal separator (with a capacity of 9++/hr) to regenerate powdered ion exchange resin, we found the following problems.

1. When scooping out light anion exchange resin, a large amount of soda mist is generated as the scraping rod comes into contact with the surface of the sodium hydroxide solution that is rotating at high speed. This means that radioactive mist is generated when used powdered ion exchange resin is treated.

2. The required motor for the experimental equipment with a throughput of 9 y/hr is 6 KW. This is because the drum of the centrifugal separator rotates in the atmosphere, so air resistance is large and the required power is also large. This inevitably means that the device will be of great importance, and in order to ensure safety, the device will have an even more robust structure.

3. Driving something that rotates at high speed in the atmosphere is
The drum generates heat due to frictional force, which may reduce separation efficiency.

It turns out that there are some problems like this.

[Purpose of the invention]

An object of the present invention is to provide a regeneration system for powdered ion exchange resin that eliminates the problems of the prior art by using a centrifugal separator system equipped with a cooling device.

[Summary of the invention]

The features of the present invention are to solve the above problems by installing a cooling device to cool the entire body and to collect the generated caustic soda mist.In addition, by installing a vacuum evacuation device and operating under negative pressure. By doing so, the aim is to improve safety, reduce required power, and improve separation efficiency.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIG. Third
The figure shows a sectional view of a centrifugal separator according to the present invention. In the figure, 1 is a drum drive motor, 2 is a drive shaft that transmits power to the drum, 3 is a porous hollow cylinder, 4 is an end plate thereof, 5 is a non-porous hollow cylinder, 6 is an end plate thereof, and 7 is a A fixed rod for transmitting power from the drive shaft to the end plate, 8 a cleaning pipe, 9 a fluid extraction pipe containing solids with low specific gravity, 10
11 is the filtrate discharge pipe, 12 is the drive mechanism, 13 is the supply pipe for the powdered resin to be separated,
14 is a separated resin scraping rod.

15 is a left and right drive mechanism for the scraping rod, 16 is its vertical drive mechanism, 17 is an outlet for removing the resin scraped off by the scraping rod, 21 is an outer casing, 22 is an upper lid, and 23 is a cooling trap for removing caustic soda mist. , 24 is a washing water cooling device, 25 is a casing cooling device, 26 is a cooling chiller,
27 is a vacuum pump, and 28 is a supply resin cooling device.

In this centrifuge, inside the outer casing of 21,
1 motor, 2 drive shafts 3 porous cylinders, 5
A non-porous cylinder is rotated to separate the used powdered ion exchange resin by centrifugal force. Further, in the centrifugal separator, a cleaning pipe 8, a fluid take-out pipe 9, a filtrate take-out pipe 11, a resin supply pipe 13, and the like pass through the outer casing 21 and communicate with the outside. Inside the casing,
Movable parts are provided so that the centrifuge can be moved to the optimum position. Further, the resin supply pipe 13 and the washing water supply pipe 8 are each equipped with a cooling device 24 and 28, and are cooled to an appropriate temperature by a chiller 26. 2
A casing cooling device 25 for cooling the heat generated by the rotation of the rotary cylinder is attached to the outer casing 1, and is cooled by a chiller 26. The inside of the outer casing can be brought to negative pressure by means of a vacuum pump 27 and is provided with a cooler 23 for cooling the exhaust air and removing the soda mist.

In this centrifuge, first remove the flange 22 and set the resin supply pipe, resin scraping rod, fluid take-out pipe, filtrate discharge pipe, etc. in the optimal position, then attach the flange and seal it. Next, the chiller is operated to cool each to the optimum temperature. When the cooling progresses and reaches the rated value, the vacuum pump 27 is started to create a negative pressure in the system. When the rated pressure is reached, the motor 1 is started to rotate the porous cylinder 3 and the nonporous cylinder 5, and after reaching a high speed rotation of about 1500 rl) m, a separation operation is performed. First, the tip of the filtrate discharge pipe 11 is outside the porous hollow cylinder 3. ', (), and the solid to be separated is supplied in the form of a slurry from the supply pipe 13.The liquid in the slurry is
Through the porous hollow cylinder and remaining inside the non-porous hollow cylinder, the liquid is discharged through eleven filtrate discharge pipes. After this, move the effluent discharge pipe in the circumferential direction so that the tip of the vibrator does not touch the liquid surface even at the maximum flow rate, and supply a separated liquid with a specific gravity intermediate between the two solids to be separated from the supply pipe 13. do. While supplying the separated liquid, the fluid extraction tube 9 is moved toward the outer periphery to discharge the separated liquid and solids with low specific gravity. After the discharge is completed, the liquid discharge pipe is returned to a position where it does not touch the liquid surface even at maximum flow rate. Next, the remaining separated liquid is drained.

While rotating, the filtrate discharge pipe 11 is gradually moved toward the outer circumference to discharge the separated liquid. Continue until the filtrate discharge pipe is at the outermost position. Next, for cleaning, the filtrate discharge pipe is kept at the outermost position and cooled pure water is sprayed from the J cleaning pipe, and the water after cleaning is discharged through the %11 filtrate discharge pipe. Next, the solids are discharged.

Rotation of rotating body from about 150 Orl) m to 1 Orl
) m, bring the scraping rod No. 14 close to the porous cylinder, and scrape off the solids. The scraped solids are discharged by gravity through 17 solids outlet ports.

Although this centrifuge is operated under negative pressure, the filtrate discharge pipe 11, the fluid take-out pipe 9, etc. are scraped out under centrifugal force, so they are specially designed for discharge. No pump required.

The anion and cation exchange resins separated by such a centrifugal separator are processed through the steps shown in FIG. The anion exchange resin is reused after being dehydrated, washed with water, and dehydrated. The cation exchange resin is dehydrated, washed with water, regenerated with sulfuric acid, and dehydrated and reused.

In such a centrifugal separator, if the supply slurry, washing water, and the entire centrifuge are cooled to about 10'C, the pressure will be 15 KPa, (absolute pressure 0.012 kg /
cm") i. This allows the required motor to be 175 or less compared to when operating at atmospheric pressure. In the case of the actual machine, the conventional 20KW operation for 1 hour can be reduced to 4KW. It will run for 1 hour.The cooling chiller required at this time has a capacity of 8000 Kca, 1./
h, and can be operated with a power consumption of 3KW. The required vacuum pump may have a capacity of about 100 t/m i 1, and the required power at this time is about 0.5 KW. Therefore, the centrifugal separator can be manufactured compactly and operating costs can be reduced.

In addition, the liquid extraction pipe 9, the filtrate discharge pipe 11, etc. are generated when they come into contact with the liquid surface rotating at high speed.The mist of sodium hydroxide containing radioactive materials is cooled and collected before entering the vacuum pump. This prevents it from scattering into the room, improving safety.

In the above embodiment, only a cold trap was described as the hydric soda mist removal device; however, similar effects can be obtained by using a cloth filter, a high performance particle filter (HEPA filter), or the like.

〔Effect of the invention〕

According to the present invention, there is no need for a filter for an indoor ventilation system that was conventionally required, and there is an effect that equipment costs and operating costs can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a conventional centrifuge, FIG. 2 is a regeneration flow sheet for powdered ion exchange resin, and FIG. 3 is a sectional view of a centrifugal separator according to an embodiment of the present invention. . DESCRIPTION OF SYMBOLS 1... Motor, 3... Porous hollow cylinder, 4... Non-porous hollow cylinder, 9... Fluid take-out pipe, 11 Filtrate discharge pipe, 14... Resin scraping rod, 21 ...
Outer casing, 24.25.28...Cooler, 23
... Cooling trap for removing force sorter mist, 27...
・Vacuum 1st day 2nd day

Claims (1)

[Claims] 1. In an ion exchange resin regeneration device consisting of a rotating body that rotates at high speed, a centrifugal separator for regenerating powdered ion exchange resin characterized in that a cooling device for removing mist is installed in the liquid supply system, cushing, and gas exhaust system.