Chemical stability evaluating method of fluorapatite ceramic solidification body

Abstract

The invention discloses a chemical stability evaluating method of a fluorapatite ceramic solidification body. The chemical stability evaluating method is characterized by comprising the steps that the fluorapatite ceramic solidification body with simulation time actinide nuclide is prepared; a hydrothermal reaction kettle with an outer shell made of stainless steel and a liner made of polytetrafluoroethylene is adopted as a leaching container; deionized water is adopted as a leaching agent, and the pH value is adjusted to 5-9; leaching is carried out at the temperature of 100 DEG C to 200 DEG C and the pressure of 0.101 MPa to 1.554 MPa, the conductivity of the leaching agent is tested, the concentration of ions in the leaching liquid is analyzed, the normalized leaching rate of the simulation time actinide nuclide is calculated, the phase changes before and after leaching of the solidification body are analyzed, and the chemical stability of the fluorapatite ceramic solidification body under the coupling action of heat, water, force and chemistry is evaluated. The method is simple and practical, high in operability, reasonable and visual in evaluation index, and accurate and reliable in evaluation result, and effective experiment bases and technical supports can be provided for evaluating the long-term stability and safety of the high-level waste solidification body in the deep geological disposal environment.

Description

technical field

[0001] The invention belongs to the treatment and disposal of high-level radioactive waste (abbreviated as high-level radioactive waste), and relates to a chemical stability evaluation method of fluorapatite ceramic solidified body. It is applicable to the chemical stability evaluation of the solidified minor actinide high-level radioactive waste under the multi-factor coupling action of "thermal field, water flow field, force field and chemical field" in the deep geological disposal environment. Background technique

[0002] With the increasing demand for energy in human society, the depletion of traditional fossil fuels and the gradual increase in the requirements for greenhouse gas emission control, human beings will have to face the choice of alternative energy sources. As a safe, clean and economical energy, nuclear energy is expected to replace traditional fossil energy on a large scale and is an indispensable energy for the sustainable development of h...

Examples

Embodiment 1

[0033] with Ca 2 P 2 o 7 , CaF 2 、Sm 2 o 3 As raw material, according to the chemical formula Ca 9.85 SM 0.1 (PO 4 ) 6 f 2Weigh the raw materials of each component for batching, according to the batching: grinding ball: absolute ethanol or / and water at a mass percentage of 35:15:50, mix them in a planetary ball mill and grind for 2 hours, and the obtained mixture is dried, The dried powder can be obtained, add polyvinyl alcohol sol of 3% of the dried powder mass, and then use a sieve to mix and granulate. Material; put the granulated material into a steel mold, press and form it with a pressure of 8 MPa on a hydraulic press, and then perform cold isostatic pressing on a cold isostatic press with a pressure of 80 MPa to obtain a molded green body; at 400 ° C Heat-treat the molded green body at high temperature for 5 hours for debinding, then put the degummed green body into a vacuum hot-press sintering furnace, and carry out vacuum hot-press sintering at a temperature...

Embodiment 2

[0035] with Ca 2 P 2 o 7 , CaF 2 、Sm 2 o 3 As raw material, according to the chemical formula Ca 7.75 SM 1.5 (PO 4 ) 6 f 2 Weigh the raw materials of each component for batching, according to the batching: grinding ball: absolute ethanol or / and water at a mass percentage of 55:25:20, mix them in a planetary ball mill and grind for 3 hours, and the obtained mixture is dried, The dried powder can be obtained, add polyvinyl alcohol sol with a mass of 6% of the dried powder, and then use a sieve to mix and granulate. Material; put the granulated material into a steel mold, press and form it with a pressure of 21 MPa on a hydraulic press, and then perform cold isostatic pressing on a cold isostatic press with a pressure of 170 MPa to obtain a molded green body; at 500 ° C The molded green body is heat-treated at high temperature for 7 hours for debinding, and then the degummed green body is put into a vacuum hot-pressing sintering furnace, and vacuum hot-pressing sinterin...

Embodiment 3

[0037] with Ca 2 P 2 o 7 , CaF 2 、Sm 2 o 3 As raw material, according to the chemical formula Ca 5.5 SM 3 (PO 4 ) 6 f 2 Weigh the raw materials of each component for batching, according to the batching: grinding ball: absolute ethanol or / and water in a mass percentage of 65:20:15, mix them in a planetary ball mill and grind for 5 hours, and the obtained mixture is dried. The dried powder can be obtained, add polyvinyl alcohol sol with a mass of 10% of the dried powder, and then use a sieve to mix and granulate. Material; put the granulated material into a steel mold, press and form it on a hydraulic press with a pressure of 35 MPa, and then perform cold isostatic pressing on a cold isostatic press with a pressure of 260 MPa to obtain a molded green body; at 600 ° C The molded green body is heat-treated at high temperature for 10 hours for debinding, and then the degummed green body is put into a vacuum hot-pressing sintering furnace, and vacuum hot-pressing sintering...

technical field

[0001] The invention belongs to the treatment and disposal of high-level radioactive waste (abbreviated as high-level radioactive waste), and relates to a chemical stability evaluation method of fluorapatite ceramic solidified body. It is applicable to the chemical stability evaluation of the solidified minor actinide high-level radioactive waste under the multi-factor coupling action of "thermal field, water flow field, force field and chemical field" in the deep geological disposal environment. Background technique

[0002] With the increasing demand for energy in human society, the depletion of traditional fossil fuels and the gradual increase in the requirements for greenhouse gas emission control, human beings will have to face the choice of alternative energy sources. As a safe, clean and economical energy, nuclear energy is expected to replace traditional fossil energy on a large scale and is an indispensable energy for the sustainable development of h...

Examples

Embodiment 1

[0033] with Ca 2 P 2 o 7 , CaF 2 、Sm 2 o 3 As raw material, according to the chemical formula Ca 9.85 SM 0.1 (PO 4 ) 6 f 2Weigh the raw materials of each component for batching, according to the batching: grinding ball: absolute ethanol or / and water at a mass percentage of 35:15:50, mix them in a planetary ball mill and grind for 2 hours, and the obtained mixture is dried, The dried powder can be obtained, add polyvinyl alcohol sol of 3% of the dried powder mass, and then use a sieve to mix and granulate. Material; put the granulated material into a steel mold, press and form it with a pressure of 8 MPa on a hydraulic press, and then perform cold isostatic pressing on a cold isostatic press with a pressure of 80 MPa to obtain a molded green body; at 400 ° C Heat-treat the molded green body at high temperature for 5 hours for debinding, then put the degummed green body into a vacuum hot-press sintering furnace, and carry out vacuum hot-press sintering at a temperature...

Embodiment 2

[0035] with Ca 2 P 2 o 7 , CaF 2 、Sm 2 o 3 As raw material, according to the chemical formula Ca 7.75 SM 1.5 (PO 4 ) 6 f 2 Weigh the raw materials of each component for batching, according to the batching: grinding ball: absolute ethanol or / and water at a mass percentage of 55:25:20, mix them in a planetary ball mill and grind for 3 hours, and the obtained mixture is dried, The dried powder can be obtained, add polyvinyl alcohol sol with a mass of 6% of the dried powder, and then use a sieve to mix and granulate. Material; put the granulated material into a steel mold, press and form it with a pressure of 21 MPa on a hydraulic press, and then perform cold isostatic pressing on a cold isostatic press with a pressure of 170 MPa to obtain a molded green body; at 500 ° C The molded green body is heat-treated at high temperature for 7 hours for debinding, and then the degummed green body is put into a vacuum hot-pressing sintering furnace, and vacuum hot-pressing sinterin...

Embodiment 3

[0037] with Ca 2 P 2 o 7 , CaF 2 、Sm 2 o 3 As raw material, according to the chemical formula Ca 5.5 SM 3 (PO 4 ) 6 f 2 Weigh the raw materials of each component for batching, according to the batching: grinding ball: absolute ethanol or / and water in a mass percentage of 65:20:15, mix them in a planetary ball mill and grind for 5 hours, and the obtained mixture is dried. The dried powder can be obtained, add polyvinyl alcohol sol with a mass of 10% of the dried powder, and then use a sieve to mix and granulate. Material; put the granulated material into a steel mold, press and form it on a hydraulic press with a pressure of 35 MPa, and then perform cold isostatic pressing on a cold isostatic press with a pressure of 260 MPa to obtain a molded green body; at 600 ° C The molded green body is heat-treated at high temperature for 10 hours for debinding, and then the degummed green body is put into a vacuum hot-pressing sintering furnace, and vacuum hot-pressing sintering...

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