JPH05317610A - Sludge sucking device and system using the same - Google Patents

Abstract

PURPOSE:To easily suck and transfer radioactive materials, toxic materials, etc., by installing a mixed gas jet pump having a solidified sludge crushing ring, a high pressure water supply pipe and an air supply pipe in a storage tank and sucking sludge-mixed liquid to transfer it to a sludge separating column. CONSTITUTION:In a storage tank 1, a mixed gas jet pump 5 having a solidified sludge crushing ring 6 for transferring sludge 10 from the storage tank 1 to a sludge separating column 2, a high pressure water supply pipe 7 for sucking air from an air supply pipe 8 by jetting water from water supply tank 3 as high pressure water to jet it to the pump 5 and the air supply pipe 8 are provided. Sludge mixed liquid 11 is sucked by the mixed gas jet pump 5, and at this time, the sludge deposited and solidified is also sucked to the sludge separating column 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for sucking up and transferring sludge containing radioactive substances such as waste ion exchange resins, toxic substances, and malodorous substances generated in nuclear power plants, nuclear fuel processing facilities, nuclear facilities or chemical plants. And the system using it.

[0002]

2. Description of the Related Art Conventionally, the following method or device has been used for sucking up and transferring sludge containing radioactive substances, toxic substances, malodorous substances and the like. (I) Vacuum pump (used to transfer the solution between relatively small capacity tanks in the reprocessing facility) (ii) Air lift (used to suck up the maintenance-free tank) (iii) Submersible pump ( The upper open type that handles a small volume of relatively low radioactive waste such as floor drain does not submerge the electric motor.) (Iv) Combination of centrifugal pump and agitation pump (from waste ion exchange resin storage tank which is a large storage tank) , Used to transfer the same resin to the processing equipment.) (V) Combination of centrifugal pump and ejector (used to suck up from a tank requiring maintenance free).

[0003]

However, each of the conventional methods has the following problems. First of all, there are drawbacks such as that the vacuum pump can be applied only to a dilute solution of slurry or sludge, that the slurry or sludge needs to be fine particles, and that the effective suction head has a limited suction head. Also,
The air lift has drawbacks such that it can be applied only to a dilute solution of slurry or sludge, that the slurry or sludge is fine particles, the lift is small, and it is only pumped up and has no transfer capability. The submersible pump has the drawback that the electric motor is submerged and has a small capacity. The combination of centrifugal pump and agitation pump has complicated operation procedure, the agitation pump is large, the opening at the top of the tank is large, the agitation pump holding platform is required in the tank, the resin concentration (sludge concentration ) There are drawbacks such as that adjustment is required, it cannot be applied without a nozzle on the side surface of the tank, the amount of liquid below the lowermost nozzle remains, and the opportunity for exposure is large.

Further, the combination of the centrifugal pump and the ejector is limited to sludge with small particles that can pass through the ejector, and depending on the size of the sludge particles, the suction amount,
There were drawbacks that the lower limit of the drive flow rate was limited, it was difficult to add new equipment to existing equipment, and sludge remained in the ejector when the operation was stopped. In addition to the above problems,
In particular, waste ion exchange resin generated from nuclear power plants and sludge generated from nuclear fuel processing facilities are accumulated and solidified because they are stored for a long time. The above method was not sufficient to properly transfer the sludge that had accumulated and solidified. The present invention solves the above drawbacks and problems,
Slurry containing radioactive substances, toxic substances, malodorous substances, etc.,
An object of the present invention is to provide a means for sucking up and transferring a solution containing sludge.

[0005]

The present invention relates to a storage tank for storing a sludge mixed liquid, a sludge separation tower, a water supply tank,
A high-pressure water supply pump and an air-fuel mixture jet pump, and 1) an air-fuel mixture jet pump with a solidified sludge crushing ring for transferring sludge from the reservoir to a sludge separation tower in the storage tank, 2) high pressure It has a high-pressure water supply pipe and an air supply pipe which are arranged so that air can be sucked from the air supply pipe by jetting water and jetted to a mixed air jet pump, and if necessary, 3) sludge that has settled in the storage tank A washing water jet ring for scraping is installed, and 4) a pipe for transferring the supernatant to the water supply tank in the sludge separation tower, and a part of the supernatant for extracting the supernatant and transferring it to a wastewater treatment facility. A branch is provided to provide a pipe for connecting to the air supply pipe, and the water in the water supply tank is piped to the high-pressure water supply pipe and the wash water jet ring via the high-pressure water supply pump, and the high-pressure water from the mixed jet pump A sludge sucked up apparatus characterized by and wick the sludge transfer pipe transferring the sludge separation column by.

[0006]

The present invention will now be described with reference to the illustrated embodiment. FIG. 1 is a block diagram of an embodiment of the siphoning device of the present invention,
FIG. 2 is a side view of a piping unit used in the apparatus of FIG. FIG. 3 is a plan view of the piping unit shown in FIG. 1, 2 and 3, 1 is a radioactive substance that easily solidifies,
Storage tank for storing sludge mixed liquid 11 containing sludge 10 such as hazardous substances and malodorous substances, 2 is a sludge separation tower provided above the storage tank 1, 3 is a water supply tank for supplying water 26 into the storage tank 1, and 4 is A high-pressure pump, 5 is a mixed air jet pump for sucking and transferring sludge, and 6 is a solidified sludge crushing ring. The high-pressure water is sent from the supply pipe 7 and discharged upward into the air-fuel mixture jet pump 5 (see FIG. 2), and the air supply pipe 8
Inhale more supplied air. 9 is a sludge transfer pipe. The high-pressure water supply pipe 7 / air supply pipe 8 is integrated and connected to the sludge transfer pipe 9, and air / high-pressure water is blown into the sludge transfer pipe as a jet at high speed. In the sludge separation tower 2, 12 is a sludge mixed liquid containing sludge 13, 14 is a supernatant overflow pipe of the sludge mixed liquid 12, 25 is a filter, 15 is a valve provided in the excess water feed pipe 18, and 16 is A valve installed in the supernatant overflow pipe,
Reference numeral 17 is a scraping cleaning water supply pipe, and 19 is a scraping cleaning water jet ring. Reference numerals 20 and 24 are valves provided on the sludge transfer pipe and the air supply pipe, respectively, and reference numerals 21 and 22 are valves provided on the high-pressure water supply pipe and the scraping cleaning water supply pipe, respectively.

In FIG. 2, reference numeral 23 is a pipe holding ring for holding various pipes. FIG. 4 is a bottom view of the solid sludge crushing ring 6, and 6a is a suction hole. FIG. 5 is an enlarged front view of the scraping cleaning water jet ring 19, and 19a is a high-pressure water jet hole. Next, the operation of the sludge suction device will be described. The water supply tank 3 is filled with water in advance and the valve 20,
21, 22, and 24 are opened, and the high pressure pump 4 is started.
The high-pressure water discharged from the supply pipe 7 into the air-fuel mixture jet pump 5 sucks air from the pipe 8 and is jetted. The suction port of the air-fuel mixture jet pump 5 is evacuated by the high-pressure water flow, and the solid content and water stored in the storage tank 1 through the crushing ring 6 are pumped through the suction pipe 9 together with the high-pressure water to the sludge separation tower 2 in a mixed state. increase. At the sludge separation tower 2,
The liquid and solid are separated from each other, and the solid content remains in the separation tower 2.
The liquid component is returned to the water supply tank 3 by gravity through the pipe 14,
It is used again as high-pressure water by the high-pressure pump 4. The gas component is circulated and reused again as air for mixture through the pipe 8. Although not shown, the sludge feed pipe 9 is preferably introduced tangentially so as to form a spiral with respect to the sludge separation column 2 having a circular cross section. In such a process, the solid content in the storage tank is pumped up to the sludge separation tower 2. The sludge separation tower 2 may have an appropriate structure depending on the property of the solid content. The amount of water returned to the water supply tank 3 is the sum of the amount of pressurized water and the amount of water pumped from the storage tank. Therefore, the amount corresponding to the amount of water pumped from the storage tank is passed through the overflow pipe 14 to the storage tank 1
Returned to. The solid content in the storage tank is pumped and reduced, whereas the water content circulates, so the solid content concentration in the storage tank gradually decreases. Excess water is intermittently or continuously supplied to the valve 15
Is opened and transferred to the wastewater treatment facility or temporary storage tank through the pipe 18.

The solid content sucked into the suction port by the crushing ring 6 installed at the suction port of the mixed air jet pump 5 has a shape smaller than the diameter of the mixed air jet pump,
Prevent the blockage of the suction port. The crushing ring reduces the solid content to a smaller mass than the suction diameter by the sharp edge of the ring and the suction force of the pump. Therefore, it is possible to suck and transfer a lump that is larger than the suction diameter. The solid content is pumped up from the vicinity of the air intake jet pump inlet, but if the fluidity is poor, the solid content concentration becomes lean near the inlet.
The valve 22 is opened, and high-pressure water is sprayed onto the wall surface from the raking wash water nozzle 19 installed at the upper end of the piping unit. The flow of water traveling along the wall surface toward the intake port of the air-fuel mixture jet pump scrapes the accumulated solid content to the intake opening and effectively pumps the solid content. As shown in FIG. 2, the piping installed in the tank is integrated by a holding ring 23, and is connected to the tank external piping by a connector via a flexible tube. Select a connector that does not leak high-pressure water or radioactive liquid. In addition, the pipes installed on the premises are
It is divided into an intermediate part and a lower end part. At the lower end, a mixed air jet pump 5, a crushing ring 6 connected to it, and a high-pressure water pipe 7 connected to an air pipe 8 are connected to the nozzle of the mixed air jet pump 5, and the total length is usually 1.5 to 2 m.
Is. The middle part is composed of pipes 7, 8 and 9 and usually has a total length of 1.5 to 2 m. An appropriate length of the intermediate portion is selected according to the depth of the tank. The upper end is in addition to the pipes 7, 8 and 9,
It consists of a scraping cleaning water ring 19 and its pipe 17, and an overflow pipe 14 of a water supply tank, with a total length of 1.5 to
It is 2m. Each part has a connector for the lower end, middle part,
They are connected in order from the upper end and installed in the tank. If a holding stand for the piping unit and a lifting tool are prepared at the opening of the tank, they can be easily connected and inserted into the tank.

Treatment Example 1 The treatment was carried out by an apparatus as shown in FIG. 1 (under the condition that the scraping ring was not operated). The mixed air jet pump has JIS 32 piping
Using A and JIS 50A, a mixed liquid obtained by mixing a waste ion exchange resin having a particle diameter of about 1 mm and almost the same amount of water is pumped. The pumping height was variable by raising and lowering the delivery pipe from the overhead crane. Under the same conditions, only water was pumped to obtain a comparative sample. The results are shown in Table 1. In each case, the wicking was carried out at a very high concentration, and the liquid transfer was carried out at a high concentration without resin retention. If the mixed jet pump is made larger, the amount of pumped liquid and the amount of pumped resin will increase, but the amount of pressurized water will decrease in the total lift under the same conditions. The pump head was sufficient for pumping from the waste sludge storage tank of the nuclear facility. When pumping progresses and the amount of resin near the suction port becomes small, the resin / water ratio decreases,
It becomes a pumping liquid with a large water content ratio. Further, when the resin was scraped near the suction port, a liquid having a high resin concentration was pumped, but the suction force of the air-mixed jet pump alone was not effective in scraping the resin.

[0010]

[Table 1]

Processing Example 2 A scraping ring as shown in FIG. 5 was used in the apparatus shown in FIG.
Water was jetted from the scraping ring, and the resin was scraped against the suction port of the air-fuel mixture jet pump 5 with a water stream. In the case of granular resin, 1 m ³ / h of water is sufficient for a wall length of 1 m. Since the discharge pressure of the high-pressure pump and the pressurized water amount of the air-fuel mixture jet pump decrease,
The scraping and pumping were performed alternately. It was able to suck up almost all the resin.

Treatment Example 3 A resin was kneaded with CMC (Carboxy Methyl Cellulose) and water to form a ball having a diameter of 30 to 90 mm and a diameter of 200 to 250 mm.
Cylinder with a height of 120-150 mm and 300 mm x 30
A 0 mm × 150 mm prism was produced. This was placed in a tank, and a crushing ring as shown in FIG. 4 was attached to the 50A mixed air jet pump 5 to carry out pumping. As a result, there was no blockage due to the resin block. In the state of being crushed and discharged by the high-pressure water in the air-jet jet pump, it had a spherical shape of about 10 mm.

[0013]

[Effects of the Invention] 1) Even when handling a substance that is strictly controlled, the driving device and the heavy device can be installed outside the tank at any place. Nuclear facilities have subdivided control areas for shielding and confining radioactivity, human access and seismic resistance of equipment installation are strictly limited in each control area, and equipment loading / unloading is also controlled. .. The tank where radioactive sludge is stored and its entrance room are strictly controlled areas. Since the radioactivity of the supernatant is lower than that of sludge, there is a great practical advantage that heavy equipment such as a high-pressure water pump that handles the supernatant can be installed in a more gently controlled area. 2) Water and air can be recycled. When applied to existing facilities, it is preferable that the amount of waste water and waste air treated is as small as possible. This can be done by recycling. Further, even in the case of a new installation, since the transfer of waste sludge is carried out 10 years after the start of operation of the facility, it is not a good idea to install pipes for waste water and waste air treatment in advance. 3) Waste resin is an organic substance, which decomposes due to radioactivity during long-term storage and is granular or powdery, and becomes caking into a solid state. Chemical sludge is an inorganic substance but alkaline, so it is hydroxylated. Fluidity deteriorates due to caking due to iron, calcium hydroxide, etc. Such items can also be processed according to the present invention. The mixed air jet pump has no throat portion and can transfer a lump having a diameter of about the same, and has a large suction force due to the vacuum at the inlet portion. By attaching a crushing ring having a diameter of about 3 to 4 times to the mixed air jet pump inlet, suction transfer can be performed with a transferable shape.

4) In the case of a centrifugal pump, it is necessary to adjust the sludge concentration in order to protect the pump and prevent clogging due to sedimentation and retention of sludge during transfer. On the other hand, in the case of the air-jet jet pump, an appropriate concentration is maintained in the transfer water, the flow velocity is high, and sedimentation is prevented by the air-mixture, so that it is possible to transfer at a high concentration. 5) A transfer ring installed inside the tank, a high-pressure water pipe, an air pipe, and a suction cleaning water pipe are integrated by a holding ring,
It has a structure that can be easily inserted from the manhole. The connection with the pipe outside the tank can be performed with a connecting metal fitting through a flexible hose, so that the handling is extremely simple. 6) Some of the waste resin and waste sludge storage tanks of nuclear facilities have a depth of 5 to 10 m, which may be deeper than the ceiling height of the room above them. This case can also be dealt with. The premises installation piping unit is divided into upper end, middle part, and lower end,
Each of them can be set to 1.5 to 2 m for easy handling. The depth of the tank can be adjusted by increasing or decreasing the intermediate portion. 7) By operating the valve, water can be jetted from the scraping cleaning nozzle to scrape the suction port sludge. 8) In other transfer methods, residue is generated in the tank by avoiding emptying because of its mechanism or to protect the pump, but since the air-jet jet pump can empty, the amount of residue is minimal. I'm done. Therefore, the number of times of cleaning is small,
Can be effectively processed. 9) The tank opening for installation may be small. Further, once installed, it is only slightly moved downward, so there are few opportunities for radiation exposure, and the radiation dose to the operator is reduced. 10) Since the high-pressure pump can be installed in a remote place, what is installed in the tank and in the vicinity of the tank are pipes, valves, and air-jet jet pumps, which are very metering. It is extremely effective when applied to existing equipment. 11) Occurrence of blockage in the air-mixed jet pump is rare, but blockage may occur when a plurality of hard lumps are simultaneously sucked into the suction port. Even in this case, the blockage can be easily eliminated by reversely injecting the high-pressure water.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of an embodiment of a sludge suction device according to the present invention.

FIG. 2 is a side view of a piping unit used in the apparatus shown in FIG.

FIG. 3 is a plan view of the piping unit shown in FIG.

FIG. 4 is a bottom view of a solid sludge crushing ring.

FIG. 5 is an enlarged front view of the scraping cleaning water jet ring.

[Explanation of symbols]

 1 Storage Tank 2 Sludge Separation Tower 3 Water Tank 4 High Pressure Pump 5 Mixed Air Jet Pump 6 Solidified Sludge Crushing Ring 7 High Pressure Water Supply Pipe 8 Air Supply Pipe 9 Sludge Transfer Pipe 10, 13 Sludge 11, 12 Sludge Mixture 14 Supernatant Liquid Overflow pipe 15, 16 valve 17 Rubbing wash water supply pipe 18 Excess water transfer pipe 19 Rubbing wash water jet ring 20, 21, 22, 24 Valve 23 Pipe holding ring 25 Filter

Claims (7)

[Claims] 1. A storage tank for storing the sludge mixed liquid,
A sludge separation tower, a water supply tank, a high-pressure water supply pump, and an air / fuel jet pump, and an air / fuel jet pump with a solidified sludge crushing ring for transferring sludge from the storage tank to the sludge separation tower in the storage tank. And a high-pressure water supply pipe and an air supply pipe arranged so as to suck air from the air supply pipe by ejecting water from the water supply tank as high-pressure water and to inject it into the air-fuel mixture jet pump. A sludge suction device characterized in that a sludge mixed liquid is sucked up by a pump and transferred to a sludge separation tower. 2. The sludge suction device according to claim 1, further comprising a wash water jet ring for scraping sludge deposited in the storage tank. 3. A sludge separation tower is provided with a pipe for transferring the supernatant liquid to a water supply tank, a branch for extracting a part of the supernatant liquid from the pipe and transferring it to a wastewater treatment facility, and further above the sludge separation tower. The sludge sucking device according to claim 1, wherein the portion is connected to an air supply pipe. 4. The sludge suction device according to claim 1, wherein the water in the water supply tank is supplied to the high-pressure water supply pipe and the wash water jet ring via a high-pressure water supply pump. 5. A sludge wicking system, characterized in that the sludge wicking apparatus according to claim 1, 2, 3 or 4 is used to circulate and use water and air used as power for an air-fuel mixture jet pump. 6. A sludge wicking system, wherein the sludge wicking apparatus according to claim 1, 2, 3 or 4 is used to unitize the equipment in the storage tank so that it can be installed from a manhole. 7. The sludge suction device according to claim 1, 2, 3 or 4, wherein the equipment in the storage tank is unitized into an upper end portion, an intermediate portion and a lower end portion, and the sludge mixed liquid is replaced according to the height of the storage tank. Sludge wicking system characterized by being adapted to