KR100219726B1 - A composition for sfpic(steel fiber polymer impregnated concrete) and a high integrity container made of the sfpic composition for low to intermediate level radioactive waste and a method for the high integrity container - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-performance container for the treatment of medium and low level radioactive waste in a nuclear power plant using steel fiber reinforced polymer impregnated concrete (SFPIC).

The present invention is to propose a basic specification of a high-integrity container to be developed in manufacturing a high-integrity container using the SFPIC, and to provide a method for producing an SFPIC having a minimum target strength of 1,000 kg / cm 2, which is the main material to be used for manufacturing the container. We propose a high-integrity container manufactured using the developed SFPIC, and test the chemical resistance and drop impact for evaluating the physical properties of the materials used and the performance of the real container in order to prove the service life of more than 300 years. About 20 kinds of proof tests such as irradiation test and irradiation. According to the manufacturing method of the high-integrity container using the SFPIC of the present invention, it is possible to improve the reliability of radioactive material management by establishing the basis for localization and standardization of the high-intelligent container as well as securing the safety and soundness of radioactive waste treatment. And it can be used as a special industrial waste treatment machine.

Description

Composition for Steel Fiber Reinforced Polymer Impregnated Concrete and Nuclear Power Plant Using It High-Intensity Container for Treating Low and Low Level Radioactive Wastes and Method for Manufacturing the Same (Steel Fiber Polymer Impregnated Concrete) and a high integrity container made of the SFPIC composition for low to intermediate level radioactive waste and a method for the high integrity container}

The present invention relates to a high integrity container for treating medium and low level radioactive waste in a nuclear power plant using steel fiber reinforced concrete impregnated concrete (SFPIC).

More specifically, the present invention relates to the treatment, storage, and transport of low and medium-level radioactive waste such as cartridge filters, ion exchange resins, worker's work clothes, and supplies for purifying cooling water generated during operation and regular inspection of nuclear power plants. It is related to high-integrity containers made of SFPIC, a composite concrete that can be used for disposal.

The methods for securing the safety and soundness of low and low level radioactive wastes generated by nuclear power plants include the solidification of radioactive waste and the use of high-intensity containers. The solidification method of the former is a complex process and generates waste. On the other hand, high-intensity containers can be treated and disposed of without desolidating the dehydrated waste (less than 1% of free water), which simplifies the treatment process and reduces the volume of waste.

On the other hand, most of the low- and low-level waste disposal containers used in domestic nuclear power plants to date are general containers composed of carbon steel and ordinary concrete, and are being stored in intermediate storage in the power plant for a long time due to the delay in constructing a permanent disposal site in Korea.

However, in view of the increase in the number of years of operation of the power plant and the increase in the amount of waste, the conventional general container described above is considered in view of the increase of the waste disposal capacity, the improvement of the management of radioactive materials, and the efficient use of the permanent disposal site to be constructed in the future. There are limitations in terms of safety and usability.

The present invention is limited to the external volume of the general container for the treatment of low and low level radioactive waste generally used in the prior art, so that the internal volume is excessively increased in consideration of the change in the internal volume depending on the material of the container. In consideration of the fact that the thickness of the container becomes thin and the thickness of the container becomes smaller, the container considering the maximum internal volume and the rigidity of the container is proposed.

Therefore, SFPIC provides high-integrity container and its manufacturing method with characteristics such as corrosion prevention of container, reduction of worker's exposure, increase of waste disposal capacity, simplification of treatment process and improvement of reliability in radiation safety management. It is to provide a composition for SFPIC for producing a container.

1 is a front cross-sectional view according to an embodiment according to the present invention.

2A is a cross-sectional view taken along the line A-A of FIG.

Figure 2b is a plan view showing a state attached to the steel plate to the SFPIC lid of Figure 1;

Figure 3 is a detailed cross-sectional view of the steel lid and drum connecting portion of FIG.

4 is a detailed view of the connection portion of the steel lid and SFPIC cap of FIG.

5 is a detail view of the fastener.

6 is a schematic flowchart showing a manufacturing process of a high integrity container according to the present invention.

* Description of the symbols for the main parts of the drawings *

1: concrete base plate 2: concrete side

3: concrete lid 4: steel drum

5: steel lid 6: epoxy sealant

7: fastener 7: steel plate

In the composition for steel fiber reinforced polymer impregnated concrete according to the present invention for achieving the above object in the composition for steel fiber reinforced polymer impregnated concrete produced by dispersing steel fiber evenly in concrete and infiltrating polymer into concrete The composition ratio is 20 to 21.5 wt% of one kind of Portland cement; 5-7 wt% of water; Fine aggregate (sand) of 24 to 26 wt%; Coarse aggregate (gravel: maximum dimension 13 mm) 40 to 42 wt%; 0.5 to 1.5 wt% of a glidant; Silica fume with 2.5 to 3 wt%; 2.5 to 3.5 wt% of a balanced steel fiber having a length of 30 mm, a diameter of 0.5 mm, and a fiber shape ratio (length / diameter) 60; A trace polymer mixture (MMA monomer, AIBN initiator, DMA) is characterized in that it is composed of a heat generating catalyst.

In addition, the method of manufacturing a high-performance container for the treatment of medium and low-level radioactive waste in nuclear power plants according to the present invention using the composition for steel fiber reinforced polymer penetrating concrete having the above composition ratio is provided with a drum and a mold after coating the drum. After mixing at a predetermined mixing ratio, the bottom surface is rubbed with SFRC, which has been rubbed, and then it is compacted, internal formwork is placed, and lining is placed, but it is placed in bulk to prevent cold joints, and then cured, dried, and polymerized. CLAIMS 1. A method for producing a radioactive container for treating radioactive waste, comprising: 20 to 21.5 wt% of one kind of portland cement; 5-7 wt% of water; Fine aggregate (sand) of 24 to 26 wt%; Coarse aggregate (gravel: maximum dimension 13 mm) 40 to 42 wt%; 0.5 to 1.5 wt% of a glidant; Silica fume with 2.5 to 3 wt%; 30 to 30mm in diameter, fiber shape ratio (length / diameter) 60 to 35 ~ 3.5wt% of the equilibrium steel fiber, and in the curing step based on 28 days of standard curing for 2 days in the air curing after removing the internal formwork Fill the container with water for the remainder of the period to cure the water in the room at a temperature of 20 ° C. In the drying step, the container is dried at 150 ° C for 24 hours in a vacuum drying furnace so that the polymer penetrates into the pores. Impregnated with a polymer solution mixed with an exothermic catalyst at 24 hours to infiltrate the pores of the dried SFRC container, and in the polymerization step, the impregnating solution is removed from the impregnated container, and then polymerized by heating at 90 ° C. for 5 hours in a vacuum drying furnace. do.

In addition, the high-performance container for the treatment of medium and low-level radioactive waste for nuclear power plants manufactured by the above-described method of the present invention comprises 20 to 21.5 wt% of one kind of portland cement; 5-7 wt% of water; Fine aggregate (sand) of 24 to 26 wt%; Coarse aggregate (gravel: maximum dimension 13 mm) 40 to 42 wt%; 0.5 to 1.5 wt% of a glidant; Silica fume with 2.5 to 3 wt%; 2.5 to 3.5 wt% of a balanced steel fiber having a length of 30 mm, a diameter of 0.5 mm, and a fiber shape ratio (length / diameter) 60; It is prepared by preparing a trace polymer mixture (MMA monomer, AIBN initiator, DMA) exothermic catalyst, characterized in that the thickness of the lid and the bottom plate is 50mm, the thickness of the side surface 40mm.

The high-tight container according to the present invention as described above establishes the basis for localization and standardization of the high-tight container for the treatment of radioactive waste in medium and low-level nuclear power plants, as well as securing the safety and soundness of the radioactive waste treatment and general and special Suitable for industrial waste disposal containers.

In the present invention, by simulating the basic specifications of the high-tight container to be developed in manufacturing a high-tight container using the SFPIC, by developing the SFPIC to develop the SFPIC of the minimum target strength of 1,000 kg / ㎠ as the main material to be used for the manufacture of the container Using the developed SFPIC, a highly sound container is manufactured according to the determined specifications. In order to prove the service life of the high-performance container obtained for more than 300 years, there are about 20 kinds of proof tests such as chemical resistance, drop impact test and irradiation test for the evaluation of the physical properties of the materials and the performance of the real containers. Was performed.

Figure 6 in the present invention is to simulate the basic specifications of the high-tight container to be developed in manufacturing a high-tight container using SFPIC, and then the design of the design of the steel fiber reinforced concrete (SFRC) (S1), the steel fiber reinforced concrete (SFRC It shows a schematic process of preparing a container (S2), infiltrating a polymer to make an SFPIC container (S3), and then completing the final performance evaluation.

As shown, in the compounding design (S1) step of the steel fiber reinforced concrete (SFRC), the material is rubbed by the compounding design of the material, the quality is evaluated accordingly, and the correction is made, and the steel fiber reinforced concrete (SFRC) container is manufactured (S2). In the steel drum, the innerform is installed, the concrete is cured, cured, demolded and modified through quality evaluation. In the manufacturing step (S3) of the SFPIC container, the cured and demolded container is vacuum dried, and the compounded penetrant is penetrated into the container and subjected to polymerization. Passing the final performance evaluation will be made a high integrity container according to the present invention completed.

Hereinafter, an SFPIC composition according to the present invention and a highly dry container using the SFPIC and a method of manufacturing the same according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings and theoretical calculation formulas.

1) Determination of Container Specifications

The high-concentration container of the present invention was developed based on an external volume of 200 l carbon steel drum in consideration of the waste treatment facility of the currently operating nuclear power plant.

Based on the above 200ℓ external volume, the experiment with actual container is the best way to determine the optimal thickness of SFPIC that has maximum internal volume and can maintain high soundness, but it requires a lot of time and cost. Therefore, the present invention simulates the drop impact test during the performance evaluation test of the high-performance container manufactured by using SFPIC through the finite element impact analysis to the thickness of each part of the SFPIC actual container of the guaranteed strength (guaranted strength) 1,000kg / ㎠ (SFPIC perforation side, bottom plate and lid thickness) were determined.

For the above impact analysis, it is assumed that the most unfavorable drop condition among various drop test methods of high-container containers falls on the concrete floor at a height of 1.2m due to the 45 ° inclination drop, and only the SFPIC container is modeled except the carbon steel drum as the safe side. Considering the workability of perforation, 40mm was set as the minimum container thickness, and modeled by increasing 5mm up to 40-50mm and analyzed the behavior of the container according to the change of thickness. At this time, the bottom thickness of the container was modeled by dividing it into four layers, and the side was divided into two layers. The outermost contact layer was made into one layer, and the inner side was divided into 2, 3 and 4 layers. The layer becomes the first contacting layer.

The simulation analyzes the effective plastic stress (von Miles stress) indicating the plasticity of the bottom plate and the x- and y-direction stresses on the side and bottom surfaces near the contact area of the container after dropping for each container thickness. The results were compared and analyzed.

As a result of the analysis by the above method, the von Miles stress in the side surface is not significantly different in the thickness change of the cross section, but the magnitude is 75% of the yield stress in the first layer (outer layer), which is significantly larger than the stress generated in the inner layer. In the case of the bottom plate, the size of the drop impact is largely dependent on its own weight, so that the larger the thickness of the cross section, the greater the stress, especially in the outermost layer.

Table 1 summarizes the results obtained by the above analysis and determines the damage value of the SFPIC container due to the maximum stress values in the x and y directions for each layer after the drop and the stress thereof.

Determination of maximum stress and damage in the x and y directions of bottom plate contact by analysis (Unit: kg / ㎠) thickness layer x (kg / ㎠) y (kg / ㎠) Remarks 40 mm One 72.80 -51.98 normal 2 -193.68 -4.48 normal 3 251.78 124.36 Smile 4 -137.60 3.96 normal 45 mm One 70.40 -53.20 normal 2 -187.52 -4.32 normal 3 248.35 121.42 Smile 4 -135.50 4.25 normal 50 mm One 71.51 -51.33 normal 2 -190.17 -4.38 normal 3 250.72 123.37 Smile 4 -135.90 4.72 normal

As shown in the results of Table 1, the SFPIC container was most impacted by the middle (third layer) of the bottom plate against the drop impact. However, since all other layers are normal, the container thickness of 40, 45 and 50 mm are all dropped. Safe cross section thickness

However, considering the stress comparison side according to the change in the thickness of the cross section, the smaller the cross section thickness is, the smaller stress is generated, which is advantageous for the drop impact.In particular, the smaller the cross section thickness is, the larger the inner volume of the container increases, so the side thickness of the container is 40mm. Is optimal, and the thickness of the bottom plate does not significantly affect the weight increase of the container during the drop impact, so it was determined to be 50 mm in consideration of the workability.

Structural model and detailed specifications of the present invention manufactured based on the above analysis results are as shown in the accompanying drawings, Figure 1 and Table 2, the connection of the steel lid and the drum, the connection of the steel lid and the SFPIC lid is a detailed drawing 2 to 4 are the same. Table 2 below shows the SFPIC high integrity container specifications.

1 shows a concrete bottom plate 1, a concrete side surface 2, a concrete lid 3, a drum 4 and a steel lid 5 of a container according to the present invention. As shown the concrete side 2 and the concrete lid 3 are sealed by an epoxy sealant 6, on which the drum 4 and the steel lid 5 are tightened and sealed by fasteners 7. In addition, a rectangular steel plate was attached to the center of the concrete lid to transport the manufactured container by magnetic force.

Preferred dimensions and doses of each site are as follows. That is, an open oval concrete structure having a height of 884, an outer diameter of 597, a thickness of a bottom plate of 50 and a thickness of 40 on the side, and an outer diameter of 572 and a thickness of 50 to cover the oval concrete structure. A concrete lid and a steel drum surrounding the concrete structure and the concrete lid, respectively, tightened and fastened by fasteners, have an external volume of 200 L, an internal volume of 141 L, and a packing weight of 172 kg. The dimensions and capacities for the container of the present invention are summarized in Table 2.

SFPIC high integrity container specifications, where H is the height of the SFPIC container, D is the diameter of the outer diameter, t1 is the thickness of the liner, d is the outer diameter, and t2 is the thickness. division Specification SFPIC Container H (mm) 884 D (mm) 597 t1 (mm) 40 SFPIC lid d (mm) 572 t2 (mm) 50 Internal volume (ℓ) 141 Package weight (kg) 172

2) Development of SFPIC

SFPIC used in the present invention is a polymer (aka polymer), a product of the polymer chemical industry, in a structural composite made by uniformly dispersing steel fibers in concrete for the purpose of greatly improving the tensile strength and resistance to cracking of concrete. It refers to a new material concrete that significantly improves physical properties such as strength, watertightness, radiation resistance, fire resistance, and chemical resistance by infiltrating (resin) into concrete.

The steel fiber used is a balanced steel fiber with a length of 30 mm, a diameter of 0.5 mm, and a fiber shape ratio (length / diameter) of 60, which is excellent in mechanical properties of the fiber itself. A fluidizing agent is used to increase workability when combining steel fiber and ordinary concrete. .

Methyl methacrylate (MMA) was used as a monomolecular monomer, and azobisiso butyronitrile (IBN) was used as an initiator, and dimethyl aniline (Demethyl Aniline: DMA) was used.

Table 3 shows a preferred embodiment of a material blending ratio and a material used to manufacture SFPIC having a guaranteed strength of 1,000 kg / cm 2 using the above materials.

Material Mixing Ratio (kg / ㎥) W / C (%) Silica fume replacement rate (%) S / a (%) cement water Fine aggregate Coarse aggregate Glidant (ℓ) Silica fume Steel fiber 28 12 37.5 550 154 650 1083 21 66 73.5

시멘트) Cement: Type 1 Portland Cement

Ii) fine aggregate: sand

골) Coarse aggregate: gravel (maximum size 13mm)

흄) silica fume: replace 12-15% of cement weight with silica fume

섬유) Steel fiber:

-Fiber length: 30mm

-Fiber diameter: 0.5mm

-Fiber shape ratio (length / diameter): 60

유동) Fluidizing agent: High strength fluidizing agent for high strength

Iii) Polymer (Polymer):

MMA + AIBN + DMA (mix AIBN 2%, DMA 1% for MMA)

3) Manufacturing process of high soundness container

The manufacture of high-integrity containers using SFPIC is composed of three processes, namely, the mixing of Steel Fiber Reinforced Concrete (SFRC), the preparation of containers, the penetration of polymer penetrants, and the polymerization process. 5 and the detailed description thereof is as follows.

(1) Drum Specification

몸체) Body and bottom plate: 1.2mm low carbon steel (KS D 3512)

Ii) Lid: 1.5mm low carbon steel (KS D 3512)

뚜껑) Lid rim: 2.3mm galvanized steel sheet (KS D 3506)

(2) drum paint

하)

-Inside: epoxy resin primer

-Outside: Meramine resin primer

Ii) Top

-Inside: epoxy resin paint (color: gray, standard: N-7)

-Outside: Meramine resin paint (Color: Yellow, Standard: 2.5Y, 4/12)

(3) formwork

외부) The external formwork uses a low-carbon steel 200 liter iron drum that forms the exterior of the SFPIC vessel and continues to be part of the vessel after its manufacture.

Ii) The inner formwork is molded inside the SFPIC container and removed after the container is manufactured, but hydraulic steel formwork is used to maintain the uniform gap (lining thickness) between the outer drum and the inner formwork and to be used repeatedly.

(4) compounding and rubbing

After putting each material according to the above mixing ratio into the mixer and dry the beams (1 minute), the fluidizing agent is put into the water, put into the mixer, and then mixed and rubbed in order of pouring.

(5) pouring and compaction

After conveying the SFRC, the bottom surface is sufficiently compacted, and then the internal formwork is mounted and the lining is poured, but it is carried out in a batch operation to prevent cold joints.

(6) curing

Based on 28 days of standard curing, remove the internal formwork after curing in the air for 2 days, and fill the container with water for the rest of the period and perform indoor aquatic curing at 20 ℃.

(7) drying

The cured container is dried at 150 ° C. for 24 hours in a vacuum drying furnace to allow the polymer to penetrate the pores.

(8) polymer penetration

The polymer solution mixed with the MMA monomer, the initiator AIBN and the promoter DMA in the above ratios is impregnated for 24 hours to infiltrate the pores of the dried SFRC vessel.

(9) polymerization

After the impregnation solution was removed from the impregnated container, a SFPIC container was prepared by polymerization in a vacuum drying furnace at 90 ° C. for 5 hours.

3) Performance evaluation test of SFPIC high integrity container according to the present invention

Highly sound containers manufactured through the above process are introduced into the concept of disposal and disposal. Most countries operating permanent disposal centers such as the United States, France, etc. have a minimum period of 300 years for administrative management. The container must have a design life of at least 300 years.

However, the design manufacturing standards for high-performance containers for satisfying such design life are not only changed according to the waste management policies and disposal site conditions of each country, but in Korea, there are no detailed standards. The high-integrity container has a useful life of more than 300 years through the physical property evaluation of the material and the container performance evaluation to meet the standards of the US Nuclear Regulatory Committee.

(1) Material property evaluation

Iii) impact and fracture toughness

The fracture toughness test shows that the SFPIC has a relatively high toughness and impact strength as shown in Table 4, as compared with conventional ordinary concrete. Table 4 shows the impact and fracture toughness test results.

Impact and Fracture Toughness Test Results Kinds Relative Impact Strength Tough fracture toughness test Ordinary concrete One One SFPIC 10 70

Ii) Creep

As a result of comparing the long-term behavior of SFPIC with SFRC, the creep coefficient of SFRC was 0.3 and the creep coefficient of SFPIC was 0.22. The creep coefficient of SFPIC was much less than that of SFRC. Compared to ordinary concrete creep coefficient, it is negligibly small. The low creep variation is the basis for SFPIC's excellent storage capacity compared to other materials. Also, since the shrinkage strain value is very small after the container is manufactured, creep is not a problem. It did not occur.

F) fatigue

As a result of comparing the fatigue behavior under cyclic load with normal concrete, the flexural fatigue strength of SFPIC was high at the higher stress level, and the higher the fatigue fatigue strength of ordinary concrete at the low stress level. The flexural fatigue strength of SFPIC was lower at the stress level lower than the maximum stress level of 80%, but this does not mean that the load bearing capacity of SFPIC is low, but only the ratio of load bearing capacity under fatigue is low. Therefore, when the same repeated flexural stress is applied, the flexural strength of SFPIC is about 2 to 3 times larger than that of ordinary concrete, so the absolute flexural fatigue strength is considered to be much higher than that of ordinary concrete.

These fatigue strengths may be subject to review depending on the storage location of the container, and may not need to be taken into account. From the results of this experiment, the steady state stress will be less than the fatigue limit, so the problem of fatigue is very high. It seems to be the safety side.

동결) freeze thawing

As a result of comparing freeze-thaw durability with normal concrete, SFPIC showed almost no weight change despite 400 freeze-thaw, while weight change of 2.2% ~ 2.3% was observed in normal concrete. In addition, in general concrete, the dynamic modulus of elasticity decreases drastically as the freezing frequency increases, whereas the dynamic modulus of SFPIC decreases very slowly. The above results suggest that SFPIC has sufficient durability against temperature changes. Table 5 shows the durability index by the freeze thaw test.

Durability Index by Freeze-thawing Test Kinds Durability Index (DF) Ordinary concrete 48 SFPIC 98

Iii) watertight castle

As a result of comparing the water-tightness change before and after polymer penetration with ordinary concrete, 300g / cm2 of water was absorbed into ordinary concrete after 200 hours in water, but SFPIC absorbed 0.15g / cm2 of water and SFPIC was compared with ordinary concrete. It can be seen that it has about 20 times watertightness.

Iii) chemical resistance

To determine the resistance of SFPIC and epoxy specimens to chemicals generated in radioactive waste or to chemicals from the environment surrounding the waste storage, each specimen is exposed to the chemical and the resulting change in compressive strength and weight is measured. Compared to US NRC standards.

The experimental results showed that the weight change of each specimen was less than ± 2%, which showed high durability against chemicals, and the change in compressive strength was slightly changed in 2% NaOH solution in SFPIC but weak in 2% H ₂ SO ₄ . Compressive strength was reduced by about 40%, and other chemicals showed more than 850㎏ / ㎠ (-15%) except Citric Acid. Although the strength decrease by H ₂ SO ₄ and Citric Acid is large, these values are considered to be safer because they are much higher than the required maximum compressive depth specified by NRC. In the case of epoxy, the change in compressive strength was slight for the whole solution.

Iii) fire resistance

As a result of measuring the weight and strength change of SFPIC under the heat condition (450 ℃) of virtual fire accident during storage and transportation, the unit weight decreased by about 2.56%. No progress was made and no signs of specimen destruction occurred. These results suggest that HICs exposed to fire or heat accidents can be repackaged and disposed of or disposed of in other HICs without loss of content.

Iii) Radiation resistant SFPIC and epoxy specimens were exposed to radiation (gamma ray). The changes in compressive strength due to radiation exposure are shown in Table 6, and these values are considered to be safe enough to meet the requirements of the maximum stored compression depth (45 ft) specified by the NRC. Table 6 shows the compressive strengths of SFPIC and epoxy.

Compressive Strength of SFPIC and Epoxy Dose (MR) Compressive strength SFPIC (㎏ / ㎠) EPOXY (kg / cm 3) 0 1000 840 50 1079 883.5 100 964 809.5 150 879 789.5

Further, the dose 50, H _2, CH _4, generation of the analysis of the CO gas in the 100M rad when are given in Table 8. Table 7 shows the gas generation analysis results.

Gas generation analysis result (Unit: 10 ^-6 mol / g) Dose (MR) H ₂ CH ₄ CO 50 m Psalm 1 2.85 6.33 10.94 Psalm 2 3.29 3.56 7.42 100 m Psalm 1 4.18 9.02 5.10 Psalm 2 4.43 13.36 8.08

Here, if the SFPIC weight of a 200 L container is calculated as 150 kg, the hydrogen generation amount of 4.31 × 10 ^-6 g-mol / g at 100MR becomes 0.65 g-mol after 300 years of radiation exposure, and the air gap of the container is calculated. Assuming a volume of 1.5 ft ³ , the hydrogen output would be 0.431 g-mol / ft ³ over 300 years. This value is 0.000394 g-mol / ft ³ , which translates into 100 days consumed in advance for transport and storage, which is about 0.62% of the NRC reference 0.063 g-mol / ft ³ . Able to know

Iii) biological resistance

After incubating the bacteria of SFPIC and epoxy specimens, the growth of bacteria and the change of compressive strength and weight were measured after a certain period of time.

As a result, after 21 days of incubation at 37 ℃, there was no growth of bacteria on both the surface and contact surface of each specimen, and the increase and decrease ratios of compressive strength and weight were within 2% and 1%, respectively. It can be said that there is no change.

UV resistance to water spray

In order to examine the degree of degradation of SFPIC due to ultraviolet rays, the experiment was performed for 3000 hours under water spray conditions while letting the specimens emit ultraviolet rays.

The test results showed that the specimens were not significantly affected by appearance, and the compressive strength of UV-irradiated SFPIC specimens was reduced by 10% compared to the original SFPIC specimens, but it is not considered to be a problem for the overall container resistance.

(2) Performance evaluation of real high integrity containers

자유) Free fall test

To assess the safety of drop impacts that may occur during transportation or handling, 1.2 m (falling weight: 0.5 m thick concrete slab) and 7.5 m (falling water) with a full container of sand and 1% free water Lower surface: 0.5m sand layer + 0.3m crushed stone layer).

As a result of the test, there was slight damage to the external drum when the floor contact was inclined at 45 °, but the integrity was maintained without spilling the contents. On the upper contact, there was some damage to the locking device of the upper lid part of the external drum, but the container maintained high soundness. . In addition, when the container side contact, damage was found to the lid of the upper lid part of the outer drum, but also maintained integrity without cracking in the concrete part.

Ii) penetration test

In order to evaluate the safety of impact load by transportation equipment or other high-container containers during transportation or handling, a cylindrical rod of 1m in length, 3.2cm in diameter, hemispherical end, and 6kg in weight is dropped from 1m height and then cracked or destroyed. Investigation of the condition revealed no signs of cracking or destruction.

I) Transportation vibration test

In order to evaluate the safety of vibrations during transportation and handling, the high-tight container filled with water-containing sand is tightly tied vertically and horizontally to the forklift and placed on the ground (40mm x 40mm) placed 0.5m apart on the ground. The vibration acceleration and cracking or damage at this time were investigated by running at an acceleration of ˜2.5g. There was no effect on the integrity of the container.

승) Lift test

In order to evaluate the safety of the accident during lifting of the container, the container filled with sand containing 1% of free water in the crane was dropped about 1m while the crane was lifted. Soundness was maintained.

Iii) burial compression test

This is to evaluate the safety of crack or damage caused by earth pressure when the container containing radioactive waste is buried upright. It is a 500 ton universal testing machine using a high-strength concrete, SFRC, SFPIC reduction container. The cracking load and ultimate strength were measured to show that the SFPIC vessel was the most stable against cracking and fracture at the maximum burial depth (45 ft). Table 8 below shows crack and fracture load results.

Crack and Fracture Load Results Kinds Crack load (kg) Breaking load (kg) Plain concrete 3,660 3,800 SFRC 7,200 7,600 SFPIC 11,608 12,240

누) Leak test

In order to evaluate the leak-tightness of the container, it was tested by applying air pressure and water pressure.

In the case of air pressure, 0.2kg / ㎠ air pressure was maintained with air compressor for about 10 minutes, but air leakage was not found in epoxy resin part, and in case of water pressure, the pressure was gradually increased to act as 1kg / ㎠. As a result of the increase and observation, no leakage was observed in the sealing part, so the overall integrity of the leakage adhesion was maintained.

Iii) water spray test

In order to examine the safety due to the rainfall effect, the container was exposed to the rainfall for 1 hour at 5cm / hr using a shower, and the impact was not observed.

Iii) fire resistance test

In order to evaluate the safety of fire accidents that may occur during handling and transportation, the weight comparison result of 3.9% weight loss after the empirical test using the reduced container of SFRC and SFPIC at the temperature of 600 ~ 800 ℃.

In addition, SFRC showed cracks and local damage on the top of the container, but SFPIC did not crack and maintained its integrity.

I) Seal performance test

To evaluate the adhesion of epoxy resin used to bond the lid and body of the container, oil jack and load cell were installed in the container, and the load of the epoxy resin was measured. Table 9 below shows the sealing test results.

Seal test result weight 200ℓ container Adhesion resistance (㎏) 2480 Adhesive Strength (㎏ / ㎠) 4.24

As a result of the test, the content of the 200 liter container is about 260 kg, whereas the maximum adhesive load is 2480 kg, which has sufficient adhesion to maintain the soundness of the contents.

As described above, by utilizing the high-integrity container using the SFPIC of the present invention, it is possible to improve the reliability of radioactive material management by establishing the basis for localization and standardization of the high-tight container, as well as securing the safety and soundness of radioactive waste treatment. It can also be used for general and special industrial waste disposal containers.

Claims (3)

In the composition for steel fiber reinforced polymer penetrating concrete prepared by dispersing steel fiber evenly in concrete and infiltrating polymer into concrete, 20 to 21.5 wt% of one kind of Portland cement; 5-7 wt% of water; Fine aggregate (sand) of 24 to 26 wt%; Coarse aggregate (gravel: maximum dimension 13 mm) 40 to 42 wt%; 0.5 to 1.5 wt% of a glidant; Silica fume with 2.5 to 3 wt%; 2.5 to 3.5 wt% of a balanced steel fiber having a length of 30 mm, a diameter of 0.5 mm, and a fiber shape ratio (length / diameter) 60; A composition for steel fiber reinforced polymer impregnated concrete, characterized in that it is composed of a trace polymer mixture (MMA monomer, AIBN initiator, DMA) exothermic catalyst. Install the drum, paint the drum, install the formwork, mix it at a predetermined compounding ratio, hit the bottom surface with grated SFRC, compact it, place the internal formwork and place the lining, but pour it in bulk to avoid cold joints. In the method of manufacturing a high-performance container for the treatment of medium and low-level radioactive waste in nuclear power plants after curing, drying and polymerization, The predetermined SFRC compounding ratio is 20 to 21.5 wt% of one kind of Portland cement; 5-7 wt% of water; Fine aggregate (sand) of 24 to 26 wt%; Coarse aggregate (gravel: maximum dimension 13 mm) 40 to 42 wt%; 0.5 to 1.5 wt% of a glidant; Silica fume with 2.5 to 3 wt%; It is set as 2.5-3.5 wt% of the equilibrium steel fiber of length 30mm, diameter 0.5mm, and fiber shape ratio (length / diameter) 60, In the curing step, Based on 28 days of standard curing, remove the internal formwork after curing in the air for 2 days, and fill the container with water for the rest of the time to cure indoors at 20 ℃. In the drying step, The curing vessel is dried in a vacuum drying furnace for 24 hours for 24 hours to infiltrate the pores of the polymer, In the polymer penetration step, The polymer solution mixed with the exothermic catalyst was impregnated for 24 hours to infiltrate the pores of the dried SFRC vessel, In the polymerization step, After removing the impregnating solution from the impregnated container, a method for producing a high-integrity container for treating medium and low level radioactive waste in a nuclear power plant, characterized in that the polymerization is carried out by heating at 90 ° C. for 5 hours. In a conventional high-health container used for the treatment of medium and low level radioactive waste in a nuclear power plant, 20 to 21.5 wt% of one kind of Portland cement; 5-7 wt% of water; Fine aggregate (sand) of 24 to 26 wt%; Coarse aggregate (gravel: maximum dimension 13 mm) 40 to 42 wt%; 0.5 to 1.5 wt% of a glidant; Silica fume with 2.5 to 3 wt%; 2.5 to 3.5 wt% of a balanced steel fiber having a length of 30 mm, a diameter of 0.5 mm, and a fiber shape ratio (length / diameter) 60; Prepared with a trace polymer mixture (MMA monomer, AIBN initiator, DMA) exothermic catalyst, A high-strength container for the treatment of medium and low level radioactive waste at a nuclear power plant, wherein the lid and bottom plate are 50 mm thick and 40 mm thick.

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