CN116959767A - Full-laser curing method for radioactive waste liquid based on iron phosphate glass - Google Patents
Full-laser curing method for radioactive waste liquid based on iron phosphate glass Download PDFInfo
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- CN116959767A CN116959767A CN202310805613.1A CN202310805613A CN116959767A CN 116959767 A CN116959767 A CN 116959767A CN 202310805613 A CN202310805613 A CN 202310805613A CN 116959767 A CN116959767 A CN 116959767A
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- crucible
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- glass
- phosphate glass
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- 239000005365 phosphate glass Substances 0.000 title claims abstract description 108
- 229910000398 iron phosphate Inorganic materials 0.000 title claims abstract description 106
- WBJZTOZJJYAKHQ-UHFFFAOYSA-K iron(3+) phosphate Chemical compound [Fe+3].[O-]P([O-])([O-])=O WBJZTOZJJYAKHQ-UHFFFAOYSA-K 0.000 title claims abstract description 106
- 239000007788 liquid Substances 0.000 title claims abstract description 87
- 239000002901 radioactive waste Substances 0.000 title claims abstract description 75
- 238000001723 curing Methods 0.000 title claims abstract description 23
- 238000000034 method Methods 0.000 claims abstract description 65
- 238000007711 solidification Methods 0.000 claims abstract description 50
- 230000008023 solidification Effects 0.000 claims abstract description 50
- 239000011521 glass Substances 0.000 claims abstract description 47
- 238000004093 laser heating Methods 0.000 claims abstract description 29
- 239000007787 solid Substances 0.000 claims abstract description 27
- 230000002285 radioactive effect Effects 0.000 claims abstract description 25
- 238000001704 evaporation Methods 0.000 claims abstract description 15
- 230000008020 evaporation Effects 0.000 claims abstract description 14
- 235000019353 potassium silicate Nutrition 0.000 claims abstract description 10
- 238000001354 calcination Methods 0.000 claims abstract description 5
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 26
- 238000010438 heat treatment Methods 0.000 claims description 25
- 238000002844 melting Methods 0.000 claims description 22
- 230000008018 melting Effects 0.000 claims description 22
- 238000001816 cooling Methods 0.000 claims description 19
- 238000000137 annealing Methods 0.000 claims description 15
- 239000002699 waste material Substances 0.000 claims description 14
- 229910052742 iron Inorganic materials 0.000 claims description 13
- 238000003860 storage Methods 0.000 claims description 13
- 238000006243 chemical reaction Methods 0.000 claims description 12
- 239000000463 material Substances 0.000 claims description 11
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 8
- 238000003723 Smelting Methods 0.000 claims description 8
- 239000000203 mixture Substances 0.000 claims description 8
- 238000007789 sealing Methods 0.000 claims description 8
- 238000004140 cleaning Methods 0.000 claims description 7
- 239000000156 glass melt Substances 0.000 claims description 7
- 230000001681 protective effect Effects 0.000 claims description 7
- 238000007670 refining Methods 0.000 claims description 7
- 239000011159 matrix material Substances 0.000 claims description 6
- 239000000843 powder Substances 0.000 claims description 6
- 238000010257 thawing Methods 0.000 claims description 6
- 238000009933 burial Methods 0.000 claims description 5
- 238000005352 clarification Methods 0.000 claims description 5
- 230000002787 reinforcement Effects 0.000 claims description 4
- 239000005368 silicate glass Substances 0.000 claims description 3
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 2
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims description 2
- 239000010439 graphite Substances 0.000 claims description 2
- 229910002804 graphite Inorganic materials 0.000 claims description 2
- 229910001220 stainless steel Inorganic materials 0.000 claims description 2
- 239000010935 stainless steel Substances 0.000 claims description 2
- 239000012780 transparent material Substances 0.000 claims 1
- 238000010521 absorption reaction Methods 0.000 abstract description 12
- 239000005388 borosilicate glass Substances 0.000 abstract description 5
- 230000007774 longterm Effects 0.000 abstract description 3
- DPTATFGPDCLUTF-UHFFFAOYSA-N phosphanylidyneiron Chemical compound [Fe]#P DPTATFGPDCLUTF-UHFFFAOYSA-N 0.000 abstract description 2
- 231100001261 hazardous Toxicity 0.000 abstract 1
- 238000005406 washing Methods 0.000 description 20
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 12
- 239000007789 gas Substances 0.000 description 11
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 10
- 238000009833 condensation Methods 0.000 description 8
- 230000005494 condensation Effects 0.000 description 8
- 239000002927 high level radioactive waste Substances 0.000 description 8
- 238000000746 purification Methods 0.000 description 8
- 229910052751 metal Inorganic materials 0.000 description 7
- 239000002184 metal Substances 0.000 description 7
- 239000002925 low-level radioactive waste Substances 0.000 description 5
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 4
- 238000010586 diagram Methods 0.000 description 4
- 229910001873 dinitrogen Inorganic materials 0.000 description 4
- 230000006698 induction Effects 0.000 description 4
- 229910052757 nitrogen Inorganic materials 0.000 description 4
- 239000010453 quartz Substances 0.000 description 4
- 230000001105 regulatory effect Effects 0.000 description 4
- 239000002912 waste gas Substances 0.000 description 4
- 239000000919 ceramic Substances 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 239000006060 molten glass Substances 0.000 description 3
- 229910052786 argon Inorganic materials 0.000 description 2
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- 229910010293 ceramic material Inorganic materials 0.000 description 2
- 239000000109 continuous material Substances 0.000 description 2
- 230000001276 controlling effect Effects 0.000 description 2
- 230000007797 corrosion Effects 0.000 description 2
- 238000005260 corrosion Methods 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- 230000000630 rising effect Effects 0.000 description 2
- 238000003756 stirring Methods 0.000 description 2
- 238000005728 strengthening Methods 0.000 description 2
- 239000000758 substrate Substances 0.000 description 2
- 239000003570 air Substances 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 239000010431 corundum Substances 0.000 description 1
- 229910052593 corundum Inorganic materials 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 229910003439 heavy metal oxide Inorganic materials 0.000 description 1
- 238000011065 in-situ storage Methods 0.000 description 1
- 239000000155 melt Substances 0.000 description 1
- 238000010309 melting process Methods 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 230000005855 radiation Effects 0.000 description 1
- 239000011214 refractory ceramic Substances 0.000 description 1
- 230000003252 repetitive effect Effects 0.000 description 1
- 238000001029 thermal curing Methods 0.000 description 1
- 238000002207 thermal evaporation Methods 0.000 description 1
Classifications
-
- G—PHYSICS
- G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
- G21F—PROTECTION AGAINST X-RADIATION, GAMMA RADIATION, CORPUSCULAR RADIATION OR PARTICLE BOMBARDMENT; TREATING RADIOACTIVELY CONTAMINATED MATERIAL; DECONTAMINATION ARRANGEMENTS THEREFOR
- G21F9/00—Treating radioactively contaminated material; Decontamination arrangements therefor
- G21F9/04—Treating liquids
- G21F9/06—Processing
- G21F9/16—Processing by fixation in stable solid media
- G21F9/162—Processing by fixation in stable solid media in an inorganic matrix, e.g. clays, zeolites
-
- G—PHYSICS
- G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
- G21F—PROTECTION AGAINST X-RADIATION, GAMMA RADIATION, CORPUSCULAR RADIATION OR PARTICLE BOMBARDMENT; TREATING RADIOACTIVELY CONTAMINATED MATERIAL; DECONTAMINATION ARRANGEMENTS THEREFOR
- G21F9/00—Treating radioactively contaminated material; Decontamination arrangements therefor
- G21F9/28—Treating solids
- G21F9/30—Processing
- G21F9/301—Processing by fixation in stable solid media
- G21F9/302—Processing by fixation in stable solid media in an inorganic matrix
- G21F9/305—Glass or glass like matrix
Landscapes
- Chemical & Material Sciences (AREA)
- Inorganic Chemistry (AREA)
- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- High Energy & Nuclear Physics (AREA)
- Processing Of Solid Wastes (AREA)
Abstract
The invention discloses a full-laser heating curing method based on hazardous elements in radioactive waste liquid contained in iron phosphate glass. The method can treat solid residues obtained from radioactive waste liquid in the modes of rotary calcination, microwave evaporation and the like, and can also directly treat high, medium and low radioactive waste liquid with various sources. Compared with borosilicate glass, the iron phosphate glass has higher inclusion rate for radioactive elements and super-strong laser absorption efficiency. Therefore, the laser curing based on the iron-phosphorus glass does not need ultra-high power laser and does not need to limit a continuous laser mode. More importantly, as the laser power or the laser energy can be set in a reasonable range, the method can adopt a crucible with opaque laser wavelength or a crucible with transparent laser wavelength, including a disposable crucible without a discharge hole and a reusable crucible with a discharge hole. The characteristics expand the application range of the iron phosphate glass and the laser application range in the radioactive waste liquid glass solidification, and especially improve the stability and the reliability of the long-term work of the laser solidification engineering.
Description
Technical Field
The invention relates to the field of radioactive waste liquid treatment, in particular to laser application in radioactive waste liquid glass solidification, mainly relating to iron phosphate glass with certain iron content and matrix composition selected for different sources, a middle-low power continuous laser or a low-frequency high-energy pulse laser, and a crucible for laser solidification with transparent or opaque laser wavelength, in particular to a matching relation and a combination mode among the three.
Background
With the development and utilization of nuclear energy as one of clean and high-efficiency energy sources, the radioactive waste generated therewith is increasing. Radioactive waste is the most abundant and complex radioactive product of radioactive waste. In order to safely isolate the radioactive waste liquid from the ecological environment, the unstable radioactive waste liquid needs to be formed into a stable solidified body by a solidification treatment mode and then enters the ground for permanent treatment. The glass solidified body formed by the glass solidifying technology has the characteristics of good long-term stability and high inclusion, is more convenient for the management and storage of high-level waste, and is the only solidifying mode for engineering application in the world at present.
The iron phosphate glass solidified base material has the characteristics of low melting temperature and low viscosity, and can reduce energy loss in the melting process. In addition, the prepared iron phosphate glass has good radiation resistance stability and higher inclusion capacity for heavy metal oxides contained in nuclear waste, and is widely paid attention to.
At present, the radioactive waste liquid glass solidification method is a first generation induction heating metal melting furnace, namely a one-step pot-type process; a second generation induction heating metal melting furnace two-step process; third generation of Joule heating ceramic furnace glass solidification technology; fourth generation cold crucible glass solidification technology.
The one-step pot process is to fuse high-level waste liquid and glass base material in metal pot through medium frequency induction heating, and anneal to form cured glass nuclear waste. The pot method has low process yield, short service life of the melting furnace and the like. The two-step method is an evaporation and induction metal melting furnace method, and the high-level waste liquid is subjected to high-temperature evaporation and then is converted into residues in the form of oxides, and then the residues and the glass substrate are mixed, melted and annealed in the metal melting furnace to form a glass solidified body. The two-step process is to pretreat radioactive waste, reduce corrosion of metal melting furnace, and raise the processing capacity of melting furnace, but the complicated process has serious heat loss. The ceramic smelting furnace method of the Joule heating furnace is that special refractory ceramic material is arranged in the smelting furnace, and a discharge valve is arranged below the ceramic material, so that continuous feeding of high-level waste liquid can be realized. The radioactive waste liquid and the glass substrate can be simultaneously added into the melting furnace to complete the decomposition of the radioactive waste liquid and the glass melting, and the method has the advantages of simple process, large treatment capacity and prolonged service life of the melting furnace. The crucible wall used in the cold crucible method is made by directly heating a metal tube by using an alternating magnetic field generated by high-frequency current, and the vortex flow during melt stirring ensures the uniformity of the melt. The water cooling circulation sleeve is arranged in the crucible wall, so that a glass solid layer close to the water cooling pipe can be used as a cold crucible for melting materials, and the corrosion resistance of the furnace body is improved.
Chinese patent CN 114724738A discloses a high-power laser-based high-level waste liquid glass solidification method. The first step of the method adopts a two-step method is traditional microwave heating and drying, evaporating high-level waste liquid, and laser heating is not used. Next, the second step of glass solidification uses ultra-high power laser to heat the glass melting furnace. The laser heating of the invention limits the laser to be in a continuous laser mode, is only suitable for high-level waste liquid, omits medium-low-level waste liquid, and has lower flexibility in laser selection. The invention uses high-level waste liquid to solidify glass by borosilicate glass, and the melting furnace for solidification is made of opaque material. The borosilicate glass has extremely low absorption efficiency on laser, and has to be limited to use an ultra-high power continuous laser, further has to be limited to use an opaque crucible, and finally, the incidence direction of the laser can be limited only from top to bottom.
Disclosure of Invention
In order to overcome the defects of the prior art, the invention provides a full-laser curing method for radioactive waste liquid based on iron phosphate glass, which directly treats the high, medium and low radioactive waste liquid with various sources through matching and combination among the iron phosphate glass, a laser and a crucible. Compared with borosilicate glass, the invention has higher inclusion rate for radioactive elements and stronger laser absorption efficiency. There is no need for high power lasers nor for defining the continuous laser mode. More importantly, since the laser power or laser energy can be set in a reasonable range, the method can be used for preparing a crucible with opaque laser wavelength or a crucible with transparent laser wavelength. The invention expands the application range of the iron phosphate glass and the laser application range in the nuclear waste solidification and improves the stability and the reliability of the long-term work of the laser solidification engineering.
The technical scheme of the invention is as follows:
in one aspect, the invention provides an all-laser curing method for radioactive waste liquid based on iron phosphate glass, which is characterized by comprising the following steps:
step 1: pretreating nuclear waste liquid to obtain solid residues;
step 2: according to the radioactive waste liquid source item, adopting a certain proportion of iron phosphate glass, wherein the glass is prepared from a specific matrix component which contains certain iron content and is designed for the source item;
step 3: and (3) respectively or mixedly adding the solid residue obtained in the step (1) and the iron phosphate glass obtained in the step (2) into a crucible for laser solidification, and heating by utilizing laser irradiation so as to heat and melt the solid residue and the iron phosphate glass together to complete the reaction, the exhaust, the clarification and the refining of the high-temperature glass melt.
Further, the method further comprises the following steps:
step 4: repeating step 1-3 or step 2-3, again feeding radioactive residues and iron phosphate glass until the glass body is substantially full of the crucible;
step 5: reducing the laser output and finally turning off the laser to finish the laser solidification of the iron phosphate glass of the radioactive residues;
step 6: and (3) feeding the iron phosphate glass again, starting a laser, sealing the crucible opening, and cooling.
Step 7: starting the laser again to heat the cooled iron phosphate glass solidified body and performing high-temperature precise annealing for a certain time at a specific temperature; then gradually reducing the laser output, and controlling the iron phosphate glass solidified body to be cooled to room temperature;
step 8: carrying out laser cleaning and impact reinforcement on the surface of the crucible, then removing the crucible, and preparing to store the whole crucible and carry out geological burial;
step 9: and moving the crucible into a new crucible, and repeating the steps.
Preferably, the method for pretreating radioactive waste liquid in step 1 includes a laser heating method in addition to a rotary calcination method, a microwave heating method, and the like. The latter treatment method is to put radioactive waste liquid into a crucible, then put a certain proportion of iron phosphate glass powder into the crucible, and perform laser heating and evaporation under the state that the crucible is stationary or rotating. When no liquid exists in the crucible, repeating the steps for a plurality of times to obtain the solid residue of the radioactive waste liquid. The crucible containing the solid residue is then moved to a laser solidification system, and iron phosphate glass is poured into the crucible until the glass body substantially fills the crucible. And then carrying out the steps 5-9.
On the other hand, the invention also provides a full-laser curing method for radioactive waste liquid based on the iron phosphate glass, which is characterized by comprising the following steps:
step 1: according to the radioactive waste liquid source item, adopting a certain proportion of iron phosphate glass, wherein the glass is prepared from a specific matrix component which contains certain iron content and is designed for the source item;
step 2: and (2) placing the radioactive waste liquid to be solidified into a crucible, adding a certain proportion of the iron phosphate glass powder obtained in the step (1), and carrying out laser heating and evaporation under the state that the crucible is stationary or rotating. When no liquid exists in the crucible, repeating the steps for a plurality of times to obtain the solid residue of the radioactive waste liquid.
Further, the method further comprises the following steps:
step 3: feeding the iron phosphate glass again until the glass body is substantially full of the crucible; heating by utilizing laser irradiation to heat and melt radioactive waste nuclear glass in a crucible, and finishing the reaction, exhaust, clarification and refining of the high-temperature glass melt;
step 4: reducing the laser output and finally turning off the laser to finish the laser solidification of the iron phosphate glass of the radioactive residues;
step 5: and (3) feeding the iron phosphate glass again, starting a laser, sealing the crucible opening, and cooling.
Step 6: starting the laser again to heat the cooled iron phosphate glass solidified body and performing high-temperature precise annealing for a certain time at a specific temperature; then gradually reducing the laser output, and controlling the iron phosphate glass solidified body to be cooled to room temperature;
step 7: carrying out laser cleaning and impact reinforcement on the surface of the crucible, then removing the crucible, and preparing to store the whole crucible and carry out geological burial;
step 8: and moving the crucible into a new crucible, and repeating the steps.
Preferably, an outlet is arranged below the crucible for laser solidification, and after the radioactive solid residues and the iron phosphate glass are heated, melted, reacted, exhausted and clarified, a valve of a discharge hole is opened to leak glass liquid into a storage barrel to be buried for solidification.
For the two schemes:
the ratio of the radioactive waste liquid to the glass is about 100:0.01 to 100:10000. the iron phosphate glass composition has an iron content adjustment range of 0.25% -75% depending on the curing laser power or energy.
The crucible can be transparent such as quartz glass, silicate glass, phosphate glass and the like, and can also be a ceramic crucible or a composite crucible made of materials such as stainless steel, alumina, graphite and the like. The crucible size and shape must be matched to the output of the laser used. The crucible is arranged on a device capable of rotating and displacing up and down, and the bottom of the crucible can be designed in a hemispherical shape or a flat bottom shape. The crucible can be designed without a discharge hole, and can also be designed with a discharge hole. The discharge gate valve can adopt the freeze thawing valve, can adopt the mode of laser heating to open the freeze thawing valve. And a protective atmosphere is adopted around the crucible.
The laser can be continuous laser output or pulse laser output. The laser itself or its output end has power or energy regulating device, the highest output capacity of the laser can be selected in the interval of 100-10000W, and has 1-100% power or energy adjustable range, and can be regulated in real time according to the requirements of various stages of heating melting, glass smelting, cooling solidification, annealing heating, constant temperature, cooling, etc. of the radioactive waste liquid glass solidification. The laser beam of the laser needs to be provided with a functional device for shifting back and forth, left and right, up and down and scanning the periphery of the crucible.
The crucible is heated by a single laser beam of a laser beam. The direction of the single-beam laser heating crucible can be the directions of right above, right below, above side, below side, normal incidence on the side, oblique incidence on the side and the like, and the crucible is provided with a moving device, so that the crucible can continuously rotate and vertically translate, and the uniformity of laser scanning of the crucible is ensured.
The crucible is heated by adopting a laser heating mode and adopting double light beams. The directions of the double-beam laser heating crucible can be directions of direct upper direction parallel, direct lower direction parallel, oblique upper crossing, oblique lower crossing, direct upper direction parallel, oblique upper oblique lower crossing, left and right direct lateral parallel or crossing, left and right oblique lateral parallel or crossing and the like.
The crucible is heated by adopting a laser heating mode and adopting three light beams and more. The directions of the three-beam laser heating crucible adopt one side surface right above and below, three sides surface right above and below, one side surface obliquely above and below, and the like.
The crucible periphery, the material upper part and the laser beam space are protected by adopting protective atmosphere, and the atmosphere around the crucible can be air, oxygen, nitrogen, argon or mixed gas of the air, the oxygen, the nitrogen and the argon.
The invention has the technical effects that:
1) The laser heating method can be used for treating solid residues obtained from radioactive waste liquid by rotary calcination, microwave evaporation and the like, and can also be used for directly treating high, medium and low radioactive waste liquid with various sources.
2) Compared with borosilicate glass, the iron phosphate glass has higher inclusion rate for radioactive elements and super-strong laser absorption efficiency. The laser curing based on the iron-phosphorus glass does not need high-power laser and does not need to limit a continuous laser mode.
3) Because the laser power or the laser energy can be set in a reasonable range, the method can adopt the crucible with opaque laser wavelength and the crucible with transparent laser wavelength, including the disposable crucible without a discharge hole and the reusable crucible with a discharge hole.
Drawings
FIG. 1 is a main flow chart of an embodiment of the present invention in which a two-step process is employed to receive a solid residue from a first step by rotary calcination or microwave heating, and then a second step of laser curing is performed with iron phosphate glass.
FIG. 2 is a main flow chart of the present invention, which shows the implementation of a two-step process, wherein the first step is to heat the radioactive waste liquid by laser to obtain a solid residue, and then to perform a second step of laser curing by using iron phosphate glass.
FIG. 3 is a main flow chart of an embodiment of the present invention for performing laser heating evaporation and laser heating curing processes in situ using a one-step disposable crucible technique.
FIG. 4 is a main flow chart of an embodiment of the present invention employing a one-step repetitive crucible discharge technique for continuous laser thermal evaporation and laser thermal curing process.
FIG. 5 is a schematic diagram showing the structure of a crucible in an embodiment of the method for solidifying iron phosphate glass for treating nuclear waste liquid by using a disposable crucible according to the present invention.
FIG. 6 is a schematic diagram showing the structure of a crucible in an embodiment of the method for solidifying iron phosphate glass for treating nuclear waste liquid by using a disposable crucible in a two-step method according to the present invention.
FIG. 7 is a schematic diagram of an embodiment of a method for solidifying iron phosphate glass by treating nuclear waste liquid in a one-step continuous material leakage manner.
FIG. 8 is a schematic structural diagram of an embodiment of the method for solidifying iron phosphate glass by treating nuclear waste liquid in a two-step continuous material leakage manner.
Fig. 9 is a schematic view of a structure of a single beam laser heating crucible.
Fig. 10 is a schematic view of a structure of a double beam laser heating crucible.
Fig. 11 is a schematic view of a structure of a three-beam laser heating crucible.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention.
Example 1 laser curing of radioactive waste solutions from certain sources based on iron phosphate glass was performed as follows:
1) The solid residue is obtained from the radioactive waste liquid by a microwave evaporation oven.
2) Iron phosphate glass having an iron content of about 25% for glass curing, in a radioactive solid residue to glass ratio of about 1:3, stirring and mixing, and then putting into a crucible for laser curing. A protective atmosphere is adopted around the crucible.
3) Treatment of high-level tail gas
The radioactive waste gas discharged from the residual furnace is collected intensively, and is first subjected to countercurrent washing by a water washing tower. The washing liquid discharged from the water washing tower is returned to the residual furnace. The waste gas after washing is subjected to purification processes such as condensation and absorption again, and finally discharged into the atmosphere. The residual low-level waste liquid generated in the purification processes of condensation, absorption and the like is totally returned to the post-treatment plant.
4) The radioactive waste liquid is prepared for underground storage after being exhausted, refined, solidified and sealed by a crucible
A single-beam laser with adjustable power is used as a crucible heat source, the maximum output power of laser is 100W, and objects in the crucible are directly heated. Introducing laser beams into the iron phosphate glass in the crucible, and adopting single-beam normal incidence on the side surface of the crucible wall. The iron phosphate glass absorbs the laser beam energy and conducts part of the energy to the radioactive residues so that both heat up and melt together. And (3) increasing the laser output until the mixture in the crucible is completely melted, and maintaining the laser output to finish the reaction, the exhaust and the refining of the high-temperature glass melt. The iron phosphate glass batch is again fed until the glass body substantially fills the crucible. The laser output is reduced and finally the laser is turned off, so that the laser solidification of the iron phosphate glass of the radioactive residues is completed. And (3) feeding the iron phosphate glass again, starting a laser, sealing the crucible opening, and cooling.
5) The radioactive solidification is annealed and removed and prepared for buried storage
And restarting the laser to heat the cooled iron phosphate glass solidified body and performing high-temperature precision annealing at a specific temperature for a certain time. Then the laser output is gradually reduced, and the iron phosphate glass solidified body is controlled to be cooled to the room temperature. And (3) performing laser cleaning and reinforced impact on the surface of the crucible by adopting a pulse laser, removing the crucible, and preparing to store the whole crucible and burying the whole crucible geology. And installing a new crucible and solidifying the waste liquid of a new round.
The laser output end of the process serving as a crucible heat source is provided with a power or energy adjusting device, the maximum output power is 1000W, the power or energy adjustable range is 1-100%, and the process can be adjusted in real time according to the requirements of the stages of heating and melting, glass smelting, cooling and solidifying, annealing, heating, constant temperature, cooling and the like of the radioactive waste liquid glass solidification. The laser beam of the laser needs to be provided with a functional device for shifting back and forth, left and right, up and down and scanning the periphery of the crucible.
The process adopts a quartz glass crucible with a transparent crucible. The crucible is protected by nitrogen gas around the crucible so as to reduce chemical reaction between the inner wall of the crucible and the materials. The crucible size and shape must be matched to the output of the laser used. The crucible is arranged on a device capable of rotating and moving up and down, and the bottom of the crucible adopts a flat bottom design. The crucible adopts a design without a discharge hole.
Example 2 full laser curing of radioactive waste liquid from a source based on iron phosphate glass was performed as follows:
1) The radioactive waste liquid and the iron phosphate glass powder with the iron content of 5 percent are mixed according to the proportion of about 100:1, respectively putting the crucible for laser evaporation. The crucible is heated by laser in a state that the crucible rotates to evaporate so as to obtain solid residues of radioactive waste liquid. When no liquid exists in the crucible, repeating the steps for a plurality of times to obtain the solid residue of the radioactive waste liquid.
2) The crucible containing the solid residue is then moved to a laser solidification system, and iron phosphate glass is poured into the crucible until the glass body substantially fills the crucible.
3) Treatment of high-level tail gas
The radioactive waste gas discharged from the residual furnace is collected intensively, and is first subjected to countercurrent washing by a water washing tower. The washing liquid discharged from the water washing tower is returned to the residual furnace. The waste gas after washing is subjected to purification processes such as condensation and absorption again, and finally discharged into the atmosphere. The residual low-level waste liquid generated in the purification processes of condensation, absorption and the like is totally returned to the post-treatment plant.
4) The radioactive waste liquid is prepared for underground storage after being exhausted, refined, solidified and sealed by a crucible
The double-beam laser with adjustable power is used as a crucible heat source to directly heat objects in the crucible. And introducing laser beams into the iron phosphate glass in the crucible, and obliquely entering the side surface of the crucible wall by adopting double beams. The iron phosphate glass absorbs the laser beam energy and conducts part of the energy to the radioactive residues so that both heat up and melt together. And (3) increasing the laser output until the mixture in the crucible is completely melted, and maintaining the laser output to finish the reaction, the exhaust and the refining of the high-temperature glass melt. The iron phosphate glass batch is again fed until the glass body substantially fills the crucible. The laser output is reduced and finally the laser is turned off, so that the laser solidification of the iron phosphate glass of the radioactive residues is completed. And (3) feeding the iron phosphate glass again, starting a laser, sealing the crucible opening, and cooling.
5) The radioactive solidification is annealed and removed and prepared for buried storage
And restarting the laser to heat the cooled iron phosphate glass solidified body and performing high-temperature precision annealing at a specific temperature for a certain time. Then the laser output is gradually reduced, and the iron phosphate glass solidified body is controlled to be cooled to the room temperature. And (3) carrying out laser cleaning and impact strengthening on the surface of the crucible by adopting a pulse laser, removing the crucible, and preparing to bury and store the whole crucible. And installing a new crucible and solidifying the waste liquid of a new round.
The laser output end of the process serving as a crucible heat source is provided with a power or energy adjusting device, the maximum output power is 1000W, the power or energy adjustable range is 1-100%, and the process can be adjusted in real time according to the requirements of the stages of heating and melting, glass smelting, cooling and solidifying, annealing, heating, constant temperature, cooling and the like of the radioactive waste liquid glass solidification. The laser beam of the laser needs to be provided with a functional device for shifting back and forth, left and right, up and down and scanning the periphery of the crucible.
The process adopts a silicate glass crucible with a transparent crucible. The crucible is protected by nitrogen gas around the crucible so as to reduce chemical reaction between the inner wall of the crucible and the materials. The crucible size and shape must be matched to the output of the laser used. The crucible is arranged on a device capable of rotating and moving up and down, and the bottom of the crucible adopts a flat bottom design. The crucible adopts a design without a discharge hole.
Example 3 full laser curing of radioactive waste liquid from a source based on iron phosphate glass was performed as follows:
1) The radioactive waste liquid and the iron phosphate glass powder with the iron content of about 30 percent are mixed according to the proportion of about 100:3, charging into a crucible for laser curing.
2) The double-beam laser with adjustable power is used as a crucible heat source to directly heat objects in the crucible, and the crucible is in a rotating state. The iron phosphate glass absorbs the laser beam energy and conducts part of the energy to the radioactive residues, so that the two are heated and evaporated together.
The crucible is a quartz crucible, and the periphery of the quartz crucible is filled with nitrogen as protective gas. Introducing laser beams into the iron phosphate glass in the crucible, and adopting normal incidence of the side surface of the double-beam crucible wall.
3) Laser heating is maintained, and when there is no liquid in the crucible, the feeding and evaporation of the radioactive waste liquid and a small amount of iron phosphate glass are repeated until the radioactive solid residue solid in the crucible reaches 1/3 of the volume of the disposable crucible. The iron phosphate glass batch is again fed until the glass is substantially full of the crucible. And (3) increasing the laser output power until the mixture in the crucible is completely melted, and then maintaining the laser output to finish the reaction, the exhaust and the refining of the high-temperature glass melt. The laser output is reduced and finally the laser is turned off, so that the laser solidification of the iron phosphate glass of the radioactive residues is completed. And (3) feeding the iron phosphate glass again, starting a laser, sealing the crucible opening, and cooling.
4) Treatment of high-level tail gas
The radioactive waste gas discharged from the residual furnace is collected intensively, and is first subjected to countercurrent washing by a water washing tower. The washing liquid discharged from the water washing tower is returned to the residual furnace. The waste gas after washing is subjected to purification processes such as condensation and absorption again, and finally discharged into the atmosphere. The residual low-level waste liquid generated in the purification processes of condensation, absorption and the like is totally returned to the post-treatment plant.
5) The radioactive solidification is annealed and removed and prepared for buried storage
And restarting the laser to heat the cooled iron phosphate glass solidified body and performing high-temperature precision annealing at a specific temperature for a certain time. Then the laser output is gradually reduced, and the iron phosphate glass solidified body is controlled to be cooled to the room temperature. And (3) carrying out laser cleaning and impact strengthening on the surface of the crucible by adopting a pulse laser, removing the crucible, and preparing to bury and store the whole crucible. And installing a new crucible and solidifying the waste liquid of a new round.
The laser output end of the process serving as a crucible heat source is provided with a power or energy adjusting device, the maximum output power is 1000W, the power or energy adjustable range is 1-100%, and the process can be adjusted in real time according to the requirements of the various stages of heating and melting, glass smelting, cooling and solidifying of the radioactive waste liquid glass solidification, heating, constant temperature, cooling and the like of annealing and the evaporation of the radioactive waste liquid. The laser beam of the laser needs to be provided with a functional device for shifting back and forth, left and right, up and down and scanning the periphery of the crucible.
The process adopts a quartz glass crucible with a transparent crucible. The crucible is protected by nitrogen gas around the crucible so as to reduce chemical reaction between the inner wall of the crucible and the materials. The crucible size and shape must be matched to the output of the laser used. The crucible is arranged on a device capable of rotating and moving up and down, and the bottom of the crucible adopts a flat bottom design. The crucible adopts a design without a discharge hole.
Example 4 full laser curing of radioactive waste solutions from certain sources based on iron phosphate glass was performed as follows:
1) The radioactive waste liquid and the iron phosphate glass with the iron content of about 30 percent are mixed according to the proportion of about 100:3, charging into a crucible for laser curing.
2) An adjustable three-beam laser with maximum power of about 1000W is used as a crucible heat source, and the directions of the beams are respectively right-left symmetrical normal incidence and upper normal incidence of the side face of the crucible wall. The iron phosphate glass absorbs the laser beam energy and conducts part of the energy to the radioactive residues, so that the two are heated and evaporated together. A protective atmosphere is adopted around the crucible. The bottom of the crucible is provided with an outlet.
The crucible is a quartz crucible, and the periphery of the quartz crucible is filled with nitrogen as protective gas. Introducing laser beams into the iron phosphate glass in the crucible, and adopting normal incidence of the side surface of the double-beam crucible wall.
3) The laser heating is maintained and the feeding and evaporation of the radioactive waste and a small amount of iron phosphate glass are repeated until the solids in the crucible reach 1/3 of the volume of the disposable crucible. The iron phosphate glass batch is again fed until the glass is substantially full of the crucible. The laser output power is increased until the mixture in the crucible is completely melted.
4) Treatment of high-level tail gas
The radioactive waste gas discharged from the residual furnace is collected intensively, and is first subjected to countercurrent washing by a water washing tower. The washing liquid discharged from the water washing tower is returned to the residual furnace. The waste gas after washing is subjected to purification processes such as condensation and absorption again, and finally discharged into the atmosphere. The residual low-level waste liquid generated in the purification processes of condensation, absorption and the like is totally returned to the post-treatment plant.
5) Leaking molten glass condensate, annealing radioactive condensate in a charging basket, sealing, and preparing for underground storage
After the temperature rise, melting, reaction, exhaust and clarification of the molten glass condensate are completed, a discharge port valve is opened, and the molten glass is leaked into a storage barrel to be buried for solidification. The discharge port valve adopts a freeze thawing valve, and the freeze thawing valve is opened by adopting a laser heating mode. And after the glass liquid in the crucible leaks out, repeatedly feeding the glass liquid into the crucible, and repeatedly heating, melting and discharging until the storage barrel is full of the seal. And restarting the laser to heat the cooled iron phosphate glass solidified body and performing high-temperature precision annealing at a specific temperature for a certain time. Then the laser output is gradually reduced, and the iron phosphate glass solidified body is controlled to be cooled to the room temperature. The storage bucket is removed and the entire bucket is ready for burial storage. And (5) replacing the empty barrel to start a new round of nuclear waste liquid solidification.
The process adopts a laser output end with a power or energy regulating device, the maximum output power is 1000W, the power or energy adjustable range is 1-100%, and the process can be regulated in real time according to the requirements of the stages of temperature rising and melting, glass smelting, temperature lowering and solidification of radioactive waste liquid glass solidification, temperature rising, constant temperature, temperature lowering and the like of annealing. The laser beam of the laser needs to be provided with a functional device for shifting back and forth, left and right, up and down and scanning the periphery of the crucible.
The process adopts a corundum crucible. The crucible is protected by nitrogen gas around the crucible so as to reduce chemical reaction between the inner wall of the crucible and the materials. The crucible size and shape must be matched to the output of the laser used. The crucible is arranged on a device capable of rotating and moving up and down, and the bottom of the crucible adopts a hemispherical design. The crucible adopts the design that the lower part has the discharge gate.
Four schemes of the method for implementing full laser solidification on high-medium low-radioactivity waste liquid based on the iron phosphate glass are respectively aimed at a one-step two-step method, the iron phosphate glass with different matrixes and iron contents, the number and the direction of laser beams, the crucible adopts a matching relation and a combination mode between a disposable crucible and a discharge hole below the crucible.
Finally, it should be noted that the above examples are only four preferred embodiments of the present invention, and should not be used to limit the scope of the present invention. Although the present disclosure describes embodiments, not every embodiment includes only a single embodiment, and the embodiments of the present disclosure may be combined appropriately to form other embodiments that will be understood by those skilled in the art.
Claims (12)
1. The full-laser curing method for radioactive waste liquid based on the iron phosphate glass is characterized by comprising the following steps of:
step 1: pretreating radioactive waste liquid to obtain solid residues;
step 2: according to the radioactive waste liquid source item, adopting a certain proportion of iron phosphate glass, wherein the glass is prepared from a specific matrix component which contains certain iron content and is designed for the source item;
step 3: and (3) respectively or mixedly adding the solid residue obtained in the step (1) and the iron phosphate glass obtained in the step (2) into a crucible for laser solidification, and heating by utilizing laser irradiation so as to heat and melt the solid residue and the iron phosphate glass together to complete the reaction, the exhaust, the clarification and the refining of the high-temperature glass melt.
2. The method for full laser solidification of radioactive waste liquid based on iron phosphate glass according to claim 1, further comprising:
step 4: repeating the steps 1-3 or 2-3, and feeding the radioactive residues and the iron phosphate glass again, wherein the steps are repeated for a plurality of times until the crucible is basically full of the glass body;
step 5: reducing the laser output and finally turning off the laser to finish the laser solidification of the iron phosphate glass of the radioactive residues;
step 6: and (3) feeding the iron phosphate glass again, starting a laser, sealing the crucible opening, and cooling.
Step 7: starting the laser again to heat the cooled iron phosphate glass solidified body and performing high-temperature precise annealing for a certain time at a specific temperature; then gradually reducing the laser output, and controlling the iron phosphate glass solidified body to be cooled to room temperature;
step 8: carrying out laser cleaning and impact reinforcement on the surface of the crucible, then removing the crucible, and preparing to store the whole crucible and carry out geological burial;
step 9: and moving the crucible into a new crucible, and repeating the steps.
3. The method for full laser solidification of radioactive waste liquid based on iron phosphate glass according to claim 1 or 2, wherein the method for pretreatment of waste liquid in step 1 further comprises a laser heating method in addition to a rotary calcination method, a microwave heating method, and the like. The latter treatment method is to put radioactive waste liquid into a crucible, then put a certain proportion of iron phosphate glass powder into the crucible, and perform laser heating and evaporation under the state that the crucible is stationary or rotating. When no liquid exists in the crucible, repeating the steps for a plurality of times to obtain the solid residue of the radioactive waste liquid. The crucible containing the solid residue is then moved to a laser solidification system, and iron phosphate glass is poured into the crucible until the glass body substantially fills the crucible. Steps 5-9 of claim 2 are performed again.
4. The full-laser curing method for radioactive waste liquid based on the iron phosphate glass is characterized by comprising the following steps of:
step 1: according to the radioactive waste liquid source item, adopting a certain proportion of iron phosphate glass, wherein the glass is prepared from a specific matrix component which contains certain iron content and is designed for the source item;
step 2: and (2) placing the radioactive waste liquid to be solidified into a crucible, adding a certain proportion of the iron phosphate glass powder obtained in the step (1), and carrying out laser heating and evaporation under the state that the crucible is stationary or rotating. When no liquid exists in the crucible, repeating the steps for a plurality of times to obtain the solid residue of the radioactive waste liquid.
5. The method for full laser solidification of radioactive waste based on iron phosphate glass according to claim 4, further comprising:
step 3: feeding the iron phosphate glass again until the glass body is substantially filled in the crucible in the step 2; the radioactive waste and the glass in the crucible are heated and melted together by utilizing laser irradiation heating, and the reaction, the exhaust, the clarification and the refining of the high-temperature glass melt are completed.
Step 4: reducing the laser output and finally turning off the laser to finish the laser solidification of the iron phosphate glass of the radioactive residues;
step 5: and (3) feeding the iron phosphate glass again, starting a laser, sealing the crucible opening, and cooling.
Step 6: starting the laser again to heat the cooled iron phosphate glass solidified body and performing high-temperature precise annealing for a certain time at a specific temperature; then gradually reducing the laser output, and controlling the iron phosphate glass solidified body to be cooled to room temperature;
step 7: carrying out laser cleaning and impact reinforcement on the surface of the crucible, then removing the crucible, and preparing to store the whole crucible and carry out geological burial;
step 8: and moving the crucible into a new crucible, and repeating the steps.
6. The method for full laser solidification of radioactive waste liquid based on iron phosphate glass according to any one of claims 1 to 5, wherein an outlet is arranged below the crucible for laser solidification, and after the radioactive solid residues and the iron phosphate glass are heated, melted, reacted, exhausted and clarified, a valve of a discharge outlet is opened to leak the glass liquid into a storage barrel to be buried for solidification.
7. The iron phosphate glass of any one of claims 1-6, prepared with a ratio of a specific matrix composition and varying iron content, wherein the ratio of radioactive waste to glass used ranges from about 100:0.01 to 100:10000. the iron phosphate glass composition has an iron content adjustment range of 0.25% -75% depending on the curing laser power or energy.
8. The method for full laser solidification of radioactive waste liquid based on iron phosphate glass according to any one of claims 1 to 6, wherein the crucible can be made of transparent materials such as quartz glass, silicate glass and phosphate glass, or can be made of opaque materials such as stainless steel, alumina and graphite. The crucible size and shape must be matched to the output of the laser used. The crucible is arranged on a device capable of rotating and displacing up and down, and the bottom of the crucible can be designed in a hemispherical shape or a flat bottom shape. The crucible can be designed without a discharge hole, and can also be designed with a discharge hole. The discharge gate valve can adopt the freeze thawing valve, can adopt the mode of laser heating to open the freeze thawing valve. And a protective atmosphere is adopted around the crucible.
9. The method for full laser solidification of radioactive waste liquid based on iron phosphate glass according to any one of claims 1 to 6, wherein the laser may be a continuous laser output or a pulsed laser output. The highest output capacity of the laser can be selected in a 100-10000W interval, the laser itself or the output end thereof is provided with a power or energy adjusting device, the power or energy adjusting range is 1-100%, and the laser can be adjusted in real time according to the requirements of the stages of heating melting, glass smelting, cooling solidification, annealing heating, constant temperature, cooling and the like of the radioactive waste liquid glass solidification. The laser beam of the laser needs to be provided with a functional device for shifting back and forth, left and right, up and down and scanning the periphery of the crucible.
10. The laser beam of any one of claims 1-6, wherein the crucible is heated by a single laser beam, either directly projected into the crucible or through the crucible wall. The direction of the single-beam laser heating crucible can be the directions of right above, right below, above side, below side, normal incidence on the side, oblique incidence on the side and the like, and the crucible is provided with a moving device, so that the crucible can continuously rotate and vertically translate, and the uniformity of laser scanning of the crucible is ensured.
11. The laser beam of any one of claims 1-6, which is projected directly into the crucible or through the crucible wall, wherein the crucible is heated by means of a laser, and wherein the crucible is heated by means of a double beam. The directions of the double-beam laser heating crucible can be directions of direct upper direction parallel, direct lower direction parallel, oblique upper crossing, oblique lower crossing, direct upper direction parallel, oblique upper oblique lower crossing, left and right direct lateral parallel or crossing, left and right oblique lateral parallel or crossing and the like.
12. The laser beam according to any one of claims 1-6, wherein the laser beam is projected directly into the crucible or through the crucible wall, and wherein the crucible is heated by laser heating using three or more beams. The directions of the three-beam laser heating crucible adopt one side surface right above and below, three sides surface right above and below, one side surface obliquely above and below, and the like.
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