JPS61208423A - Thermal disposal of waste ion exchange resin - Google Patents

Abstract

PURPOSE:To simplify the facilities, make the operation easy and reduce cost by supplying a waste ion exchange resin in water slurry state to an incinerator for which a revolving flame flow is held near the supply inlet of the incinerator to burn the waste resin. CONSTITUTION:If the gain size of a waste ion exchange resin in a water slurry is under 100 mesh, it is first crushed to 100 mesh with a crusher 20, and then it is supplied to a constant volume pump 2. A water slurry that contains a waste ion exchange resin in powder state is supplied to a slurry supply inlet 5 of an incinerator 4 through a supply line 3. A hot air wind generating furnace 6 is supplied with air and fuel to generate a hot air wind which develops a revolving flame flow in the incinerator 4. A fuel gas is supplied to the incinerator 4 to effect preheating and temperature holding for the incinerator 4. The hot air wind generated in the hot air furnace 6 is blown near the water slurry supply inlet 5 of the incinerator 4 through a revolving flame flow generating nozzle 9 to generate a revolving flame flow.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for incinerating waste ion exchange resin, and in particular to a method for incinerating radioactive waste ion exchange resin generated at nuclear power plants. A method for incinerating waste ion exchange resin that makes it possible to simplify equipment, simplify operations, and reduce costs by incinerating waste ion exchange resin in the form of slurry in an incinerator that maintains a swirling flame flow. Regarding.

[Prior art] Stored in an upper tank. In particular, in boiling water nuclear power plants, 200 TIl of waste ion exchange resin is generated per unit per year. There is a problem with overcoming it. In view of these circumstances, attempts have been made in recent years to reduce the volume of waste ion exchange resins by incinerating them. Common incineration methods include:
Fixed bed furnaces, fluidized bed furnaces, circular single-stage furnaces, etc. are known, but in fixed bed furnaces, the particle size of the waste ion exchange resin is too small, making it difficult to hold it on the grate in the furnace. cannot be applied; in a fluidized bed furnace, it is difficult to maintain a fluidized bed due to the formation of heat spots due to partial combustion and the formation of salts such as Na C! and Na 2804; There are drawbacks such as the difficulty of maintenance and inspection, which requires work under radiation because of the equipment involved.Therefore, in addition to the general radioactive combustible waste incineration treatment method, a unique incineration treatment method using waste ion exchange resin has recently been developed. Various proposals have been made, such as JP-A No. 59-88700, JP-A No. 59-159100, and JP-A No. 59-138.
This is disclosed in Publication No. 23 and the like.

[Problems to be Solved by the Invention] Japanese Patent Application Laid-Open No. 59-88700 discloses that combustible waste is mixed with combustible gas and then supplied to an incinerator to form a mixture of combustible gas and oxygen. A method for incinerating combustible waste by passing it through a high-temperature flame is disclosed. however,
Although this method reduces the amount of waste gas generated since oxygen is essential, it has the drawback of high cost.

JP-A-59-159100 discloses a method in which waste ion exchange resin is dried and powdered, iron oxide or iron powder of fine particle size is added thereto, and then incinerated. This method requires a process of drying and powdering the waste ion exchange resin, which is complicated to operate, requires large equipment, and increases costs.Furthermore, it is necessary to take measures to prevent dust explosions. be.

Japanese Patent Application Laid-Open No. 59-13823 discloses a method in which wetted coarse waste ion exchange resin is mixed with fuel oil and water in the presence of an emulsifier to form a stable emulgene, and then sprayed and burned. There is. This method also complicates the equipment.

The present invention has been made in order to eliminate the above-mentioned drawbacks, and aims to provide a method for incinerating waste ion-exchange resin that makes it possible to simplify equipment, simplify operations, and reduce costs. purpose.

[Means and effects for solving the problems] In order to achieve the above object, the present invention provides a method for incinerating waste ion exchange resin, in which the waste ion exchange resin in the form of water slurry is held in the vicinity of the supply port in a swirling flame stream. It is characterized by being incinerated by supplying it to an incinerator.

Hereinafter, the present invention will be explained in detail based on the drawings.

FIG. 1 is a flow sheet relating to an embodiment of a treatment system to which the waste ion exchange resin incineration treatment method of the present invention is applied.

In the figure, 1 is a water slurry introduction line that introduces waste ion exchange resin in the form of water slurry (hereinafter referred to as water slurry);
2 is a bridge for quantitatively supplying the water slurry to the incinerator 4; 3 is a water slurry supply line that supplies a water slurry of powdered waste ion exchange resin to an incinerator; 4 is an incinerator that incinerates waste ion exchange resin; 5 is a water slurry 6 is a hot air generator for generating a swirling flame flow in the incinerator 4; 7 is an air supply line; 8 is a fuel supply line; 9 is a swirling flame flow generation nozzle; 10 is a monitor for monitoring the inside of the incinerator 4. 11 is a waste gas discharge line.

In the same figure, the waste ion exchange resin in the water slurry introduction line 1 is normally in the state of water slurry, but the water content is often 75 to 95% by weight in consideration of ease and efficiency of transportation. In addition, the waste ion exchange resin in the supplied water slurry is
If the mesh size is 0.00 mesh or more, no particular pulverization process is required, but if the particle size is less than 100 mesh, such as granular waste ion exchange resin, 95% by weight or more of it is crushed by a wet pulverizer 20 to improve combustion efficiency. It is desirable to supply the metering pump 2 to the metering pump 2 after pulverizing it. Crusher 20
Although the type is not particularly limited, a two-stage batch type crusher equipped with rod crushing means and ball crushing means is preferably used. The inclination angle α of the hopper of the metering pump 2 varies depending on the moisture content and the particle size of the waste ion exchange resin, but is usually preferably 85° or more. Since this hopper is equipped with a rotating bridge breaker 21, the performance of the metering pump is ensured. The water slurry containing the powdered waste ion exchange resin is supplied to the water slurry supply port 5 of the incinerator 4 via the water slurry supply line 3. The reason why the particle size of the waste ion exchange resin in the water slurry is controlled in this way is to ensure that the incineration treatment is carried out sufficiently, as will be described in the later examples.

On the other hand, air is supplied to the hot air generating furnace 6 through an air supply line 7.
Further, fuel is supplied from a line 8a branching from the fuel supply line 8 to generate hot air for generating a swirling flame flow inside the incinerator 4. As the fuel, LPG, kerosene, etc. are preferably used.

Here, 7a is a line for supplying combustion air, and 7b is a line for supplying dilution air necessary for incineration of waste ion exchange resin.

The incinerator 4 has a line 8b branching from the fuel supply line 8.
Fuel gas is supplied from the incinerator 4 to preheat the incinerator 4 and maintain its temperature. Further, the hot air generated in the hot blast furnace 6 is blown into the vicinity of the water slurry supply port 5 of the incinerator 4 through the swirling flame flow generation nozzle 9 to generate a swirling flame flow. This swirling flame flow can be adjusted by adjusting the installation angle of the swirling flame flow generating nozzle 9, the nozzle diameter, the amount of hot air supplied from the hot air generating furnace 6, and the like. Incidentally, it is preferable that the incinerator 4 is preheated to about 1000° C. with fuel. The situation inside the furnace, such as the generation state of the swirling flame flow, can be monitored through the viewing window 10. Incineration is preferably carried out at a temperature of 1,200 to 1,400°C from the viewpoint of combustion efficiency and refractories in the furnace.

The waste gas generated here is discharged from the waste gas outlet line 11 and treated with a known waste gas treatment system.

[Explanation of Examples] Next, the present invention will be specifically explained based on examples.

First, cation (Na type): anion (CJ type)-2:
1 (volume ratio in wet state, particle size 0.38 to 0.84
ff1n+) 285g of granular ion exchange resin and 400g of water
After adding g to form a water slurry, wet pulverization treatment was performed using a two-stage pulverizer having a Rondo crushing means and a Pall crushing means.

If the crushing time and crushing time are both 1.5 minutes, 1
The passage rate through a 00 mesh (149 μm) sieve was 90.0% on an air-dry weight basis. When the crushing time was 3 minutes and the crushing time was 3 minutes, the passing rate through a 100 mesh (149 μm) sieve was 99.2%.

Next, the granular ion exchange resin was crushed for 3 minutes, and the ion exchange resin was crushed for 3 minutes.
The particle size distribution of the waste ion exchange resin obtained by pulverization in minutes and the powdered ion exchange resin [cation (H type): anion (OH type) - 2:1 (volume ratio in wet state)] The passage rate of sieves with different mesh sizes was measured. Based on this result, the average particle diameter was determined from the Ra5in-8ammler diagram. The results are shown in Table 1.

Table 1 Next, a water slurry containing powdered resin with a water content of 85.0% was pumped using a snake pump (trade name, maximum supply rate 774/h).
) was used to supply the incinerator, the result was 10 to 90K.
Quantitative supply of g/h (lit dry weight basis) was possible. It is preferable that the inclination angle α of the hopper is 85° or more, and it has been found that it is better to provide a bridge breaker to enable stable quantitative supply.

Next, the powdered resin in the form of water slurry was incinerated using a cylindrical horizontal high-speed swirling flow incinerator (combustion chamber: 350n+mφx1,000nv).

Hot air of 1200° C. or higher was generated in a hot air generating furnace, and a high-speed swirling flow with a blowing speed of 260 m/sec was blown into the combustion chamber.

On the other hand, LPG was injected into the combustion chamber, and the combustion load was set at 2,080,001 (caJ/Tl1h), and the temperature inside the combustion chamber was set at approximately 1300°C.
The temperature was 250°C and 1240°C at the outlet. When the combustion condition stabilized, a powdered ion exchange resin in the form of a water slurry with a moisture content of 185.0% was supplied to the incinerator at a rate of 123.3/(g/h (18.5 kg/h for ion exchange resin alone)). It was incinerated.

During incineration, the combustion status was visually observed through a viewing window, and the combustion status was found to be good. When the inside of the furnace was visually observed after the test, no unburned residue was found. The residence time of gas in the furnace in the combustion chamber was calculated to be 0.18 seconds.

Next, the exhaust gas is analyzed to determine combustion efficiency, weight loss rate, SO
The amount of x and the amount of dust were determined. The results are shown in Table 2. The calculation formula is as follows.

Combustion efficiency -〇〇/(CO2+CO) Reduction rate = (Supplied amount (dry weight) - Collected dust amount) Table 2 As can be seen from Table 2, according to the method of the present invention, combustion efficiency,
It was found that both the volume reduction effect and the harmful components in the waste gas were low.

[Effects of the Invention] As explained above, according to the present invention, the following effects are achieved.

■ Compared to conventional methods, the process is simpler, so equipment can be simplified and costs can be reduced.

■ Handling operations can be simplified because conventional complicated operations such as emulsification and drying are not required.

■ Costs can be reduced because combustion efficiency is good even when using only air and fuel.

■ In the present invention, there is no risk of dust explosion because the water slurry is incinerated.

[Brief explanation of the drawing]

FIG. 1 is a flow sheet relating to an embodiment of a treatment system to which the waste ion exchange resin incineration treatment method of the present invention is applied. 1.1a... Water slurry introduction line, 2... Metering pump, 3... Water slurry supply line, 4... Incinerator, 5... Supply port, 6... Hot air generating furnace, 1 ...Air introduction line, 8...Fuel supply line, 9...Swirling flame flow generation nozzle, 10...Peep window, 11...Waste gas outlet line, 20...Wet crusher, 21 ...Bridge breaker.

Claims (1)

[Scope of Claims] 1. A method for incinerating waste ion exchange resin, characterized in that the waste ion exchange resin in the form of a water slurry is incinerated by being supplied to an incinerator that maintains a swirling flame stream near the supply port. A method for incinerating waste ion exchange resin. 2. The method for incineration of waste ion exchange resin according to claim 1, wherein 95% by weight or more of the waste ion exchange resin in the form of water slurry is pulverized to 100 mesh or more by wet pulverization. 3. The water content of the waste ion exchange resin in the form of water slurry is 7.
The method for incinerating waste ion exchange resin according to claim 1 or 2, wherein the content is 5 to 95% by weight. 4. The method for incinerating waste ion exchange resin according to any one of claims 1 to 3, wherein the incineration is carried out at 1200 to 1400°C.