CN115116638A - Sodium-potassium alloy coolant pipeline system dismantling and post-processing method - Google Patents
Sodium-potassium alloy coolant pipeline system dismantling and post-processing method Download PDFInfo
- Publication number
- CN115116638A CN115116638A CN202110295332.7A CN202110295332A CN115116638A CN 115116638 A CN115116638 A CN 115116638A CN 202110295332 A CN202110295332 A CN 202110295332A CN 115116638 A CN115116638 A CN 115116638A
- Authority
- CN
- China
- Prior art keywords
- sodium
- potassium
- post
- treatment
- pipeline
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- G—PHYSICS
- G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
- G21C—NUCLEAR REACTORS
- G21C19/00—Arrangements for treating, for handling, or for facilitating the handling of, fuel or other materials which are used within the reactor, e.g. within its pressure vessel
- G21C19/34—Apparatus or processes for dismantling nuclear fuel, e.g. before reprocessing ; Apparatus or processes for dismantling strings of spent fuel elements
Landscapes
- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Plasma & Fusion (AREA)
- General Engineering & Computer Science (AREA)
- High Energy & Nuclear Physics (AREA)
- Processing Of Solid Wastes (AREA)
Abstract
The invention belongs to a system dismantling method, and particularly relates to a sodium-potassium alloy coolant pipeline system dismantling and post-processing method. A sodium-potassium alloy coolant pipeline system dismantling and post-processing method comprises the following steps: the method comprises the following steps: dismantling the area division; step two: operation preparation; step three: dismantling and post-processing operation. The invention has the following remarkable effects: the practicability is as follows: by the technical scheme, the sodium-potassium alloy heat transfer test loop is successfully dismantled, and the dismantled pipeline, equipment and sodium-potassium waste liquid are properly treated and are reliable through practice verification. The technology enables the dismantling work of the sodium-potassium device to be standardized and standardized preliminarily. The economic efficiency is as follows: the technical scheme is easy to implement, the post-treatment device is easy to obtain materials, the post-treatment device is simple to manufacture, and partial materials can adopt dismantled waste pipelines and profiles. Safety is as follows: aiming at the characteristics of sodium and potassium, the technical requirements for all operations are based on safety, and the operation safety can be high according to the technology through repeated demonstration and actual verification.
Description
Technical Field
The invention belongs to a system dismantling method, and particularly relates to a sodium-potassium alloy coolant pipeline system dismantling and post-processing method.
Background
The fast reactor coolant in the fourth generation nuclear energy system mainly comprises: sodium, lead-bismuth alloy, sodium-potassium alloy and other metal media, wherein the nuclear reaction technology taking the sodium-potassium alloy as a coolant is a main technical route of space reactor. At present, because the related technology of the reactor is still in a research stage, a ground matched test device is mainly established. The potassium alloy is extremely active in chemical property, low in melting point (liquid at room temperature), and inflammable and explosive.
In the maintenance, transformation and decommissioning of the sodium-potassium device, the operations of a pipeline with sodium-potassium, equipment cutting, welding, punching and the like are involved, and the phenomena of liquid accumulation areas, internal adhesion and the like exist because sodium-potassium cannot be completely discharged from the system. In the operation, phenomena such as air entering a sodium-potassium system and sodium-potassium outflow are easy to occur, fire or explosion is caused, the risk is extremely high, and great technical difficulty and safety protection challenge are brought to construction.
At present, domestic construction operations related to the maintenance, transformation, retirement and the like of sodium-potassium pipelines/equipment have no mature and standardized technical documents. The technology is a sodium-potassium alloy coolant pipeline system dismantling and post-processing method which is summarized, extracted and researched in successfully implemented engineering projects, and is proved to be safe and feasible.
At present, no construction guidance document of system properties exists for the dismantling and post-treatment of a sodium-potassium alloy pipeline system, and relevant papers or patents with sodium-potassium pipeline dismantling and sodium-potassium treatment are mostly developed in laboratories and other specific conditions in China atomic energy science research institute and Nuclear industry southwest physical research institute, such as: loose joint is needed on the premise of pipeline disassembly, and the waste sodium potassium treatment is not specific enough. The method has poor applicability and executability for construction units, does not have comprehensive and detailed implementation technology, and is difficult to organize workers to implement.
Disclosure of Invention
The invention aims at the defects of the prior art and provides a sodium-potassium alloy coolant pipeline system dismantling and post-processing method.
The invention is realized by the following steps:
a sodium-potassium alloy coolant pipeline system dismantling and post-processing method comprises the following steps:
the method comprises the following steps: demolition area division
Step two: preparation of the operation
Step three: dismantling and post-processing operation.
The sodium-potassium alloy coolant pipeline system dismantling and post-processing method comprises the following steps,
firstly, carrying out dismantling area division on the device, adopting a mode of combining a system flow chart, a three-dimensional model and a real object photo during division, and determining the approximate position of cutting division and the argon gas supply position by utilizing the system flow chart; on the basis of determining the cutting position according to the system flow chart, rechecking the specific cutting position according to the principle of height from top to bottom according to the three-dimensional model, and making a daily cutting area; and finally, checking the rationality of the formulated dismantling step by a field checking device entity, adjusting the scheme according to the actual situation of the field, and in the formulated dismantling step, when one part is dismantled, correspondingly changing and modifying the flow chart and the model of the rest part according to the dismantling situation, so as to always keep the states of the system flow chart, the three-dimensional model and the field object consistent.
The sodium-potassium alloy coolant pipeline system dismantling and post-processing method is characterized in that the second step comprises the following steps
(1) Environmental requirements
1) No water and fire source exists on site, and good ventilation conditions are provided;
2) the air humidity is less than or equal to 60 percent, and construction operation in rainy weather is strictly forbidden;
3) posting a safety notice on a construction site;
4) protective equipment such as steel pipes, warning lines and the like are prepared on a construction site, a warning board and a safety isolation area are arranged,
(2) technical requirement of argon protection
Before the demolition work is carried out, the argon amount required by single complete cutting work needs to be calculated, a margin is left, the argon is forbidden to be cut off in the cutting and plugging processes, the gas cylinder is replaced,
(3) protection technical requirements in operation
Cutting operators wear fireproof clothes, protective glasses, protective masks, protective leather gloves, fireproof boots and the like, and in order to prevent sodium and potassium from falling into the boots, the trouser openings are forbidden to be arranged in the boots; binding the fireproof gloves with sleeves to prevent sodium and potassium from entering the sleeves; a cape is needed to be worn to prevent sodium and potassium from dropping from the upper part and entering the inside of the clothes from the neckline; the protective mask adopts a full protection type, and a half protective mask is forbidden,
(4) technical requirements of cutting operation
1) Firstly, all the heat preservation layers and heating wires outside the loop are removed, the removed heat preservation layers and heating wires are stacked in order in the open space,
2) the sodium-potassium alloy tank, the connecting valve and the pipeline of the device are subjected to appearance inspection to check whether obvious damage or other damage exists, if so, the construction is stopped, the reason is checked, the repair is complete or isolated, if not, the construction is continued,
3) reducing the pressure of the device loop to micro-positive pressure (about 2-3 kPa), opening a sodium potassium valve corresponding to the loop to empty sodium potassium in the device loop into a storage tank or a transfer tank through self-weight, then temporarily fixing the sodium potassium storage tank to prevent the occurrence of severe shaking or dumping and the like in the construction process,
4) checking whether sodium and potassium in a loop pipeline are residual or not by methods of observing the pipeline arrangement characteristics (such as liquid bags), knocking the pipeline to hear sound and the like, marking suspicious positions, paying attention during cold cutting, then closing sodium and potassium inlet and outlet valves of a storage tank or a transfer tank,
(5) technical requirements for incision closure
The rubber plug and the steel blind plate are used for plugging the cut of the pipeline and need to be manufactured in advance in a workshop, the cut needs to be subjected to subsequent argon filling, and the rubber plug and the blind plate are provided with connecting pipes with valves and pressure gauges; when in use, the argon gas pipe is directly butted with the mouth of the argon gas supply pipe, which is convenient for the subsequent argon filling protection,
(6) pipeline containing residual sodium and potassium and technical requirements for post-treatment of equipment
Firstly, a device for post-treatment of equipment and pipelines is manufactured, the device comprises an argon or nitrogen cylinder, a steam boiler, pipelines, valves, an electric tracing band, a waste liquid collecting tray, a pressure gauge, a thermometer, a bracket and the like, one side of the device is connected with an argon steel cylinder and a small-sized movable steam boiler in the treatment process, the controllable slow oxidation of sodium and potassium in waste equipment is realized by controlling the proportion of argon and steam entering the equipment to be treated, and the sodium and potassium are converted into stable compounds,
(7) after-treatment technical requirements of sodium potassium waste liquid collected in the dismantling process
The device for post-treatment of sodium and potassium comprises a sodium and potassium treatment disc, a waste liquid collecting disc, an electric or manual sprayer, a pipeline, a protective enclosure and the like.
The sodium-potassium alloy coolant pipeline system dismantling and post-processing method is characterized in that the third step comprises the following steps
In the argon protection link, a specially-assigned person is assigned to take care of an argon meter at an air source position in the dismantling process, the person who sees the table is forbidden to leave and do other work in the whole dismantling process, the air supply pressure is ensured to be about (2-3) kPa, the residual air volume of the argon bottle is noticed, and the requirement of the required air volume in the cutting and blocking time period of a cut is ensured.
The sodium-potassium alloy coolant pipeline system dismantling and post-processing method is characterized in that the third step comprises the following steps
In the protection link during operation, the fireproof blankets are hung around the notch and isolated from an operator, the camera is inserted into the fireproof blankets and aligned with the notch, and the operator operates the fireproof blankets by observing the screen connected with the camera.
The sodium-potassium alloy coolant pipeline system dismantling and post-processing method is characterized in that the third step comprises the following steps
A cutting operation technology link, wherein before the pipeline is cut, the gas phase pressure of the pipeline is adjusted to (3-5) kPa; firstly, winding gauze in a range of 500mm from the left to the right of an incision position, pouring liquid nitrogen into a freezing pipeline, measuring the temperature of the freezing pipeline by using a point thermometer, controlling the temperature to be (-40 to-30) DEG C, controlling the argon pressure by a specially-assigned person during cutting, keeping the pressure to be (3 to 5) kPa all the time, and measuring the incision temperature by using the point thermometer at any time by an operator; a paraffin oil barrel is arranged below the pipeline cut, so that residual sodium-potassium alloy at the cut part is soaked in paraffin oil, argon flows out from the interface at the cutting position, and the pipeline is blocked after being cut off, which is detailed in the 'technical requirement for cut blocking',
the pipes and equipment removed from the apparatus were transferred to a safe area and the internal sodium potassium was treated over 72h,
when the paraffin oil drum collects the sodium-potassium waste liquid with the height of about 2cm, the cover is covered to place the iron drum in a safe area for waiting treatment, and the single drum is forbidden to collect excessive sodium-potassium waste liquid.
The sodium-potassium alloy coolant pipeline system dismantling and post-processing method is characterized in that the third step comprises the following steps
In the process of incision plugging, a subsequent argon-filled incision is not needed on the device, the incision cannot be separated from the device in the same day, the incision and the device must be welded by a steel plate, a rubber plug to be processed in the same day is used for temporary plugging, a disposable rubber glove with a hand is inserted into a pipe orifice during plugging, the glove is taken off from the plugged opening and sleeved on the plugged opening, and then the rubber is bound firmly by an adhesive tape,
when plugging, dipping the residue of the incision in paraffin oil by cotton gauze, slowly wiping the paraffin oil until the inner wall of the interface is clean and has no foreign matters, wiping the paraffin oil, and after endoscopy, sealing the interface by a blind plate or a rubber plug, particularly welding the incision and ensuring that the incision has no sodium-potassium alloy.
The sodium-potassium alloy coolant pipeline system dismantling and post-processing method is characterized in that the third step comprises the following steps
A pipeline containing residual sodium and potassium and an equipment post-treatment link, wherein during treatment, a gas cylinder valve and a pressure reduction valve are opened firstly, and the gas supply pressure is kept at 2-3 kPa, so that the air in the equipment to be treated is completely discharged; then, preheating a mixed gas pipeline, slowly opening a steam boiler gas outlet valve when the temperature of an observation point reaches 120 ℃, enabling the mixed gas of water vapor and argon to enter equipment for slow oxidation, adjusting the proportion of the mixed gas by controlling a steam valve 2 so as to adjust the reaction rate with the sodium-potassium alloy solution,
after the device reacts for a period of time, whether the reaction is sufficient can be judged by whether reaction sound exists in the lateral hearing device or not and whether sodium and potassium residues exist in the lateral hearing device or not through observing the device by using an endoscope; if the sodium-potassium alloy residue still exists, the mixed gas is continuously used for slowly oxidizing the sodium-potassium alloy residue; if no visible sodium-potassium alloy remains, plugging an opening at the lower part of the equipment, slowly injecting water into the equipment, observing while injecting water, standing for a period of time after the equipment is filled with water, and fully reacting sodium and potassium in the equipment; after the reaction is completed, the waste liquid is discharged to a collecting tray, and the alkaline waste liquid in the collecting tray is filled in a plastic bucket and is delivered to a waste liquid company for treatment.
The sodium-potassium alloy coolant pipeline system dismantling and post-processing method is characterized in that the third step comprises the following steps
A post-treatment link of collecting the sodium-potassium waste liquid in the dismantling process, conveying the sodium-potassium alloy waste liquid collected in the paraffin oil drum to a region to be treated, uniformly dumping the sodium-potassium alloy into a treatment disc with grids by using a spoon, ensuring that the sodium-potassium alloy is not gathered together due to the grids, obliquely fixing the treatment disc on a frame, placing a waste liquid collecting disc below the lower end of the treatment disc, fixing a water spray nozzle above the treatment disc,
evacuating personnel to a safe area which is 8-10 m away from the treatment disc and is isolated, starting a water sprayer in the safe area to enable the sodium-potassium alloy to fully react with water mist, collecting alkali liquor in the waste liquid disc, putting the alkali liquor in a plastic barrel, delivering the alkali liquor to a waste liquid company for treatment,
the treatment disc with the grating plate has the effects of enabling paraffin oil and sodium potassium waste liquid to be uniformly distributed, preventing the paraffin oil and the sodium potassium waste liquid from agglomerating, preventing violent reaction and reducing safety risk.
The invention has the following remarkable effects: the practicability is as follows: by the technical scheme, the sodium-potassium alloy heat transfer test loop is successfully dismantled, and the dismantled pipeline, equipment and sodium-potassium waste liquid are properly treated and are reliable through practice verification. The technology enables the dismantling work of the sodium-potassium device to be standardized and standardized preliminarily.
The economic efficiency is as follows: the technical scheme is easy to implement, the post-treatment device is easy to obtain materials, the manufacture is simple, and partial materials can adopt dismantled waste pipelines and profiles.
Safety is as follows: aiming at the characteristics of sodium and potassium, the technical requirements for all operations are based on safety, and the operation safety can be high according to the technology through repeated demonstration and actual verification.
Drawings
FIG. 1 is a schematic view of an incision occlusion system;
FIG. 2 is a system diagram of a sodium-potassium-containing pipeline and an equipment post-treatment device;
FIG. 3 is a flow chart of the post-treatment of a pipeline with a sodium potassium device;
FIG. 4 is a system diagram of a sodium potassium post-treatment device;
FIG. 5 is a view of a collection tray with a grating plate;
FIG. 6 is a top view of the grated box;
FIG. 7 is a front view of FIG. 6;
FIG. 8 is an enlarged view of a portion of FIG. 7 at position A;
FIG. 9 is a view showing a cutting removal step
Wherein 1 gas supply channel, 2 rubber plugs, 3 manometer, 4 air feed valves, 5 steel blind plates, 6 boilers, 7 valves, 8 pending treatment facility, 9 waste liquid collecting vat, 10 helium (argon) gas cylinders, 11 gas cylinder valves, 12 relief pressure valves, 13 automatic water atomizer, 14 safety isolation, 15 shower nozzles, 16 take grid to handle the dish, 17, waste liquid collecting tray, 18 water supply hose, 19 supports, 20 take the grid box, 21 leakage fluid dram
Detailed Description
A sodium-potassium alloy coolant pipeline system dismantling and post-processing method comprises the following steps:
1 demolition area division
Firstly, the device is divided into a dismantling area, and a mode of combining a system flow chart, a three-dimensional model and a real object photo is adopted during division. Determining the approximate cutting division position and the argon gas supply position by using a system flow chart; on the basis of determining the cutting position according to the system flow chart, rechecking the specific cutting position according to the principle of height from top to bottom according to the three-dimensional model, and making a daily cutting area; and finally, checking the device entity on site, verifying the reasonability of the formulated dismantling step, and adjusting the scheme according to the actual situation on site. In the step of formulating and dismantling, when one part is dismantled, the flow chart and the model of the rest part are correspondingly changed and modified according to the dismantling condition, and the states of the system flow chart, the three-dimensional model and the field object are always kept consistent.
2 formulating operational specifications
(1) Environmental requirements
1) No water and fire source exists on site, and good ventilation conditions are achieved;
2) the air humidity is less than or equal to 60 percent, and construction operation in rainy days is forbidden;
3) posting a safety notice on a construction site;
4) protective equipment such as steel pipes, warning lines and the like are prepared on a construction site, and warning boards and safety isolation areas are arranged.
(2) Technical requirement of argon protection
Before the demolition work is carried out, the argon amount required by single complete cutting work needs to be calculated, allowance is reserved, argon gas is forbidden to be cut off in the cutting and plugging processes, and the gas cylinder is replaced.
The dismantling process assigns a specially-assigned person to take care of the argon gas meter at the gas source position, and the person who looks at the argon gas meter is prohibited from leaving and doing other work in the whole dismantling process. The air supply pressure is ensured to be about (2-3) kPa. Meanwhile, the residual gas quantity of the argon bottle is noticed, and the requirement of the gas quantity required in the cutting and blocking time period of one cut is ensured.
(3) Protection technical requirements in operation
The cutting operator wears fire-proof clothes, protective glasses, protective face masks, protective leather gloves, fire-proof boots and the like. In order to prevent sodium and potassium from falling into the boots, the openings of the trousers are forbidden to be arranged in the boots; binding the fireproof gloves with sleeves to prevent sodium and potassium from entering the sleeves; a cape is needed to be worn to prevent sodium and potassium from dropping from the upper part and entering the inside of the clothes from the neckline; the protective mask is of a full-protection type, and a half-protective mask is forbidden.
The fireproof blanket is hung around the notch and is isolated from an operator, a camera is inserted into the fireproof blanket and is aligned to the notch, and the operator operates the fireproof blanket by observing a screen connected with the camera.
(4) Technical requirements of cutting operation
1) Firstly, all the heat-insulating layers and heating wires outside the loop are removed. The removed heat preservation layer and the heating wire are stacked in order in the open ground.
2) And (3) carrying out appearance inspection on the sodium-potassium alloy tank, the connecting valve and the pipeline of the device, checking whether obvious damage or other damage exists, stopping construction if the damage or other damage exists, checking the reason, repairing completely or isolating, and continuing construction if the damage does not exist.
3) The pressure in the device loop is reduced to a micro-positive pressure of about (2-3) kPa. The corresponding sodium potassium valve in the return circuit is opened, so that sodium potassium in the device return circuit is emptied into the storage tank or the transfer tank through self weight, and then the sodium potassium storage tank is temporarily fixed, so that the situations of violent shaking or dumping and the like in the construction process are prevented.
4) Whether sodium and potassium in a loop pipeline are remained or not is checked by methods of observing the arrangement characteristics (such as liquid bags) of the pipeline, knocking the pipeline to listen and the like, a suspicious part is marked, and important attention is needed during cold cutting. And then closing the sodium potassium inlet and outlet valves of the storage tank or the transfer tank.
5) The pipeline cutting mainly completes the processes of liquid nitrogen freezing, pipeline cutting and plugging,
before the pipeline is cut, the gas phase pressure of the pipeline is adjusted to be (3-5) kPa; firstly, winding gauze in the range of 500mm from the left and right of the incision position, pouring liquid nitrogen to freeze the pipeline, and measuring the temperature of the freezing pipeline by using a point thermometer, wherein the temperature is controlled to be (-40 to-30). During cutting, a specially-assigned person is arranged to control the pressure of argon gas to be always kept at (3-5) kPa, and an operator measures the temperature of the cut by using a point thermometer at any time; a paraffin oil barrel is arranged below the pipeline notch, so that residual sodium-potassium alloy at the notch part is soaked in paraffin oil, and argon flows out of the interface at the cutting position. After the pipeline is cut off, plugging is carried out, and the detailed specification is the technical requirement of the cut plugging in the following section.
The pipes and equipment removed from the apparatus were transferred to a safe area and the internal sodium potassium was treated over 72 h.
When the paraffin oil drum collects the sodium-potassium waste liquid with the height of about 2cm, the cover is covered to place the iron drum in a safe area for waiting treatment, and the single drum is forbidden to collect excessive sodium-potassium waste liquid.
(5) Technical requirements for incision closure
The rubber buffer and the steel blind plate are used for plugging the cut of the pipeline and need to be manufactured in advance in a workshop. For the incision needing subsequent argon filling, the rubber plug and the blind plate are provided with connecting pipes with valves and pressure gauges; when in use, the argon gas-filled tube is directly butted with an argon gas supply tube opening, so that the subsequent argon filling protection is facilitated, and the system diagram is shown in figure 1. For the notch on the device to be free from subsequent argon flushing, and the notch cannot be separated from the device on the same day, the notch must be welded by a steel plate. The disposable rubber gloves are inserted into the pipe openings by taking the rubber plugs, the gloves are taken off and sleeved on the plugging openings in a proper way after the rubber plugs are plugged, and then the rubber plugs are bound firmly.
When plugging, dipping the residue of the opening with cotton gauze to obtain paraffin oil, and slowly wiping until the inner wall of the opening is clean and has no foreign matters. Clean paraffin oil, and seal the interface with a blind plate or a rubber plug after endoscopy. Particularly, the notch is welded, and the notch is ensured to be free of sodium-potassium alloy.
(6) Pipeline containing residual sodium and potassium and technical requirements for post-treatment of equipment
Firstly, equipment and a device for post-treatment of pipelines are manufactured, a device system diagram is shown in figure 2, and the device comprises an argon or nitrogen bottle, a steam boiler, a pipeline, a valve, an electric tracing band, a waste liquid collecting disc, a pressure gauge, a thermometer, a bracket and the like. In the treatment process, one side of the device is connected with an argon steel cylinder and a small-sized movable steam boiler, and the ratio of argon and steam entering equipment to be treated is controlled to realize controllable slow oxidation of sodium and potassium in the waste equipment and convert the sodium and potassium into stable compounds.
During treatment, the gas cylinder valve 6 and the pressure reduction valve 7 are opened firstly, and the gas supply pressure is kept at (2-3) kPa. Completely exhausting the air in the equipment to be treated; then, preheating a mixed gas pipeline, slowly opening a steam boiler gas outlet valve when the temperature of an observation point reaches 120 ℃ and the temperature of the observation point reaches 120 ℃, so that the mixed gas of water vapor and argon enters equipment for slow oxidation. The proportion of the mixed gas is adjusted by controlling the steam valve 2, thereby adjusting the reaction rate with the sodium-potassium alloy solution.
After the device reacts for a period of time, whether the reaction is sufficient can be judged by whether reaction sound exists in the lateral hearing device or not and whether sodium and potassium residues exist in the lateral hearing device or not through observing the device by using an endoscope; if the sodium-potassium alloy residue still exists, the mixed gas is continuously used for slowly oxidizing the sodium-potassium alloy residue; if no visible sodium-potassium alloy remains, plugging an opening at the lower part of the equipment, slowly injecting water into the equipment, observing while injecting water, standing for a period of time after the equipment is filled with water, and fully reacting sodium and potassium in the equipment; after the reaction is completed, the waste liquid is discharged to a collecting tray, and the alkaline waste liquid in the collecting tray is filled in a plastic bucket and is delivered to a waste liquid company for treatment.
(7) After-treatment technical requirements of sodium potassium waste liquid collected in the dismantling process
Firstly, the device for post-treatment of sodium and potassium is manufactured, and a system diagram of the device is shown in figure 4, and the device comprises a sodium and potassium treatment disc, a waste liquid collecting disc, an electric or manual sprayer, a pipeline, a protective enclosure and the like.
The sodium-potassium alloy waste liquid collected in the paraffin oil barrel is conveyed to a region to be treated, the sodium-potassium alloy is uniformly poured into a treatment disc with grids by using a spoon, and the sodium-potassium alloy can be ensured not to be gathered together due to the grids. The treatment disc is obliquely fixed on the frame, and a waste liquid collecting disc is arranged below the lower end of the treatment disc. A water spray head is fixed above the processing disc.
People evacuate to a safe area which is 8-10 m away from the treatment disc and isolated, and a water sprayer is started in the safe area to enable the sodium-potassium alloy to fully react with water mist. Collecting the alkali liquor in the waste liquor tray in a plastic bucket and delivering the alkali liquor to a waste liquor company for treatment.
The treatment disc with the grating plates (the thickness of the grating plates is 2mm-5mm, the length and width of grating openings are about 50 mm) has the functions of enabling paraffin oil and sodium potassium waste liquid to be uniformly distributed, preventing the paraffin oil and the sodium potassium waste liquid from agglomerating, preventing violent reaction and reducing safety risks, the structure of the treatment disc with the grating plates is shown in figure 5, the detailed dimension of the box with the grating is shown in figure 6, and the dimension in the figure can be slightly adjusted.
Claims (9)
1. A sodium-potassium alloy coolant pipeline system dismantling and post-processing method is characterized in that: comprises the following steps:
the method comprises the following steps: demolition area division
Step two: preparation of the operation
Step three: dismantling and post-processing operation.
2. A sodium potassium alloy coolant piping system removal and post-treatment method as claimed in claim 1, wherein: the first step comprises the following steps of,
firstly, carrying out dismantling area division on the device, adopting a mode of combining a system flow chart, a three-dimensional model and a real object photo during division, and determining the approximate position of cutting division and the argon gas supply position by utilizing the system flow chart; on the basis of determining the cutting position according to the system flow chart, rechecking the specific cutting position according to the principle of height from top to bottom according to the three-dimensional model, and making a daily cutting area; and finally, checking the rationality of the formulated dismantling step by a field checking device entity, adjusting the scheme according to the actual situation of the field, and in the formulated dismantling step, when one part is dismantled, correspondingly changing and modifying the flow chart and the model of the rest part according to the dismantling situation, so as to always keep the states of the system flow chart, the three-dimensional model and the field object consistent.
3. A method of removing and post-treating a sodium potassium alloy coolant piping system as claimed in claim 2, wherein: the second step comprises the following steps
(1) Environmental requirements
1) No water and fire source exists on site, and good ventilation conditions are achieved;
2) the air humidity is less than or equal to 60 percent, and construction operation in rainy weather is strictly forbidden;
3) posting a safety notice on a construction site;
4) protective equipment such as steel pipes, warning lines and the like are prepared on a construction site, a warning board and a safety isolation area are arranged,
(2) technical requirement of argon protection
Before the demolition work is carried out, the argon amount required by single complete cutting work needs to be calculated, allowance is reserved, argon gas cutting-off in the cutting and plugging processes is forbidden, a gas cylinder is replaced,
(3) protection technical requirements in operation
Cutting operators wear fireproof clothes, protective glasses, protective masks, protective leather gloves, fireproof boots and the like, and in order to prevent sodium and potassium from falling into the boots, the trouser openings are forbidden to be arranged in the boots; the fireproof gloves are bound with the sleeves to prevent sodium and potassium from entering the sleeves; a cape is needed to be worn to prevent sodium and potassium from dropping from the upper part and entering the inside of the clothes from the neckline; the protective mask adopts a full protection type, and a half protective mask is forbidden,
(4) technical requirements of cutting operation
1) Firstly, all the heat preservation layers and heating wires outside the loop are removed, the removed heat preservation layers and heating wires are stacked in order in the open space,
2) the sodium-potassium alloy tank, the connecting valve and the pipeline of the device are subjected to appearance inspection to check whether obvious damage or other damage exists, if so, the construction is stopped, the reason is checked, the repair is complete or isolated, if not, the construction is continued,
3) reducing the pressure of the device loop to micro positive pressure about 2-3 kPa, opening a sodium potassium valve corresponding to the loop to empty sodium potassium in the device loop into a storage tank or a transfer tank by self weight, then temporarily fixing the sodium potassium tank to prevent the conditions of violent shaking or dumping and the like in the construction process,
4) checking whether sodium and potassium in a loop pipeline are remained or not by observing the arrangement characteristics of the pipeline (such as a liquid bag), knocking the pipeline to hear, marking a suspicious part, paying attention during cold cutting, closing a sodium and potassium inlet and outlet valve of a storage tank or a transfer tank,
(5) technical requirements for incision closure
The rubber plug and the steel blind plate are used for plugging a pipeline cut and need to be manufactured in a workshop in advance, subsequent argon is required to be filled into the cut, and the rubber plug and the blind plate are provided with connecting pipes with valves and pressure gauges; when in use, the argon gas pipe is directly butted with the mouth of the argon gas supply pipe, which is convenient for the subsequent argon filling protection,
(6) pipeline containing residual sodium and potassium and technical requirements for post-treatment of equipment
Firstly, a device for post-treatment of equipment and pipelines is manufactured, the device comprises an argon or nitrogen cylinder, a steam boiler, pipelines, valves, an electric tracing band, a waste liquid collecting tray, a pressure gauge, a thermometer, a bracket and the like, one side of the device is connected with an argon steel cylinder and a small-sized movable steam boiler in the treatment process, the controllable slow oxidation of sodium and potassium in waste equipment is realized by controlling the proportion of argon and steam entering the equipment to be treated, and the sodium and potassium are converted into stable compounds,
(7) after-treatment technical requirements of sodium potassium waste liquid collected in the dismantling process
The device for post-treatment of sodium and potassium comprises a sodium and potassium treatment disc, a waste liquid collecting disc, an electric or manual sprayer, a pipeline, a protective enclosure and the like.
4. A sodium potassium alloy coolant piping system removal and post-treatment method as claimed in claim 3, wherein: the third step comprises the following steps
In the argon protection link, a specially-assigned person is assigned to take care of an argon meter at an air source position in the dismantling process, the person who sees the table is forbidden to leave and do other work in the whole dismantling process, the air supply pressure is ensured to be about (2-3) kPa, the residual air volume of the argon bottle is noticed, and the requirement of the required air volume in the cutting and blocking time period of a cut is ensured.
5. A sodium potassium alloy coolant piping system removal and post-treatment method as claimed in claim 3, wherein: the third step comprises the following steps
In the protection link during operation, the fireproof blanket is hung around the notch and is isolated from an operator, the camera is inserted into the fireproof blanket and is aligned to the notch, and the operator operates through observing the screen connected with the camera.
6. A method of removing and post-treating a sodium potassium alloy coolant piping system as claimed in claim 3, wherein: the third step comprises the following steps
A cutting operation technology link, wherein before the pipeline is cut, the gas phase pressure of the pipeline is adjusted to (3-5) kPa; firstly, winding gauze in a range of 500mm from the left to the right of an incision position, pouring liquid nitrogen into a freezing pipeline, measuring the temperature of the freezing pipeline by using a point thermometer, controlling the temperature to be (-40 to-30) DEG C, controlling the argon pressure by a specially-assigned person during cutting, keeping the pressure to be (3 to 5) kPa all the time, and measuring the incision temperature by using the point thermometer at any time by an operator; a paraffin oil drum is arranged below the cut of the pipeline, so that the residual sodium-potassium alloy at the cut part is soaked in the paraffin oil, meanwhile, the argon gas flows out from the interface at the cutting position, and the pipeline is blocked after being cut off, in detail, the technical requirement of the cut blocking is shown in the following section,
the pipes and equipment removed from the apparatus were transferred to a safe area and the internal sodium potassium was treated within 72h,
when the paraffin oil drum collects the sodium-potassium waste liquid with the height of about 2cm, the cover is covered to place the iron drum in a safe area for waiting treatment, and the single drum is forbidden to collect excessive sodium-potassium waste liquid.
7. A sodium potassium alloy coolant piping system removal and post-treatment method as claimed in claim 3, wherein: the third step comprises the following steps
In the process of incision plugging, a subsequent argon-filled incision is not needed on the device, the incision cannot be separated from the device in the same day, the incision and the device must be welded by a steel plate, a rubber plug to be processed in the same day is used for temporary plugging, a disposable rubber glove with a hand is inserted into a pipe orifice during plugging, the glove is taken off from the plugged opening and sleeved on the plugged opening, and then the rubber is bound firmly by an adhesive tape,
when plugging, dipping the residue of the incision in paraffin oil by cotton gauze, slowly wiping the paraffin oil until the inner wall of the interface is clean and has no foreign matters, wiping the paraffin oil, and after endoscopy, sealing the interface by a blind plate or a rubber plug, particularly welding the incision and ensuring that the incision has no sodium-potassium alloy.
8. A sodium potassium alloy coolant piping system removal and post-treatment method as claimed in claim 3, wherein: the third step comprises the following steps
A pipeline containing residual sodium and potassium and an equipment post-treatment link, wherein during treatment, a gas cylinder valve and a pressure reduction valve are opened firstly, and the gas supply pressure is kept at 2-3 kPa, so that the air in the equipment to be treated is completely discharged; then, preheating a mixed gas pipeline, slowly opening a steam boiler gas outlet valve when the temperature of an observation point reaches 120 ℃, enabling the mixed gas of water vapor and argon to enter equipment for slow oxidation, adjusting the proportion of the mixed gas by controlling a steam valve 2 so as to adjust the reaction rate with the sodium-potassium alloy solution,
after the device reacts for a period of time, whether the reaction is sufficient can be judged by whether reaction sound exists in the lateral hearing device or not and whether sodium and potassium residues exist in the lateral hearing device or not through observing the device by using an endoscope; if the sodium-potassium alloy residue still exists, the mixed gas is continuously used for slowly oxidizing the sodium-potassium alloy residue; if no visible sodium-potassium alloy remains, plugging an opening at the lower part of the equipment, slowly injecting water into the equipment, observing while injecting water, standing for a period of time after the equipment is filled with water, and fully reacting sodium and potassium in the equipment; after the reaction is completed, the waste liquid is discharged to a collecting tray, and the alkaline waste liquid in the collecting tray is filled in a plastic bucket and is delivered to a waste liquid company for treatment.
9. A sodium potassium alloy coolant piping system removal and post-treatment method as claimed in claim 3, wherein: the third step comprises the following steps
A post-treatment link of collecting sodium-potassium waste liquid in the dismantling process, conveying the sodium-potassium alloy waste liquid collected in the paraffin oil drum to a region to be treated, uniformly pouring sodium-potassium alloy into a treatment disc with grids by using a spoon, ensuring that the sodium-potassium alloy is not aggregated together due to the grids, obliquely fixing the treatment disc on a rack, placing a waste liquid collecting disc below the lower end of the treatment disc, fixing a water spray nozzle above the treatment disc,
evacuating personnel to a safe area which is 8-10 m away from the treatment disc and is isolated, starting a water sprayer in the safe area to enable the sodium-potassium alloy to fully react with water mist, collecting alkali liquor in the waste liquid disc, putting the alkali liquor in a plastic barrel, delivering the alkali liquor to a waste liquid company for treatment,
the treatment disc with the grating plate has the effects of enabling paraffin oil and sodium potassium waste liquid to be uniformly distributed, preventing the paraffin oil and the sodium potassium waste liquid from agglomerating, preventing violent reaction and reducing safety risk.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110295332.7A CN115116638B (en) | 2021-03-19 | 2021-03-19 | Sodium-potassium alloy coolant pipeline system dismantling and post-processing method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110295332.7A CN115116638B (en) | 2021-03-19 | 2021-03-19 | Sodium-potassium alloy coolant pipeline system dismantling and post-processing method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN115116638A true CN115116638A (en) | 2022-09-27 |
| CN115116638B CN115116638B (en) | 2023-10-20 |
Family
ID=83324475
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110295332.7A Active CN115116638B (en) | 2021-03-19 | 2021-03-19 | Sodium-potassium alloy coolant pipeline system dismantling and post-processing method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115116638B (en) |
Citations (16)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1035330A (en) * | 1962-12-28 | 1966-07-06 | Nihon Genshiryoku Kenkyujo | Process and apparatus for treating solid radioactive wastes |
| US3808141A (en) * | 1969-09-17 | 1974-04-30 | Commissariat Energie Atomique | Process for dissolving sodium,potassium and their alloys |
| FR2523268A1 (en) * | 1982-03-11 | 1983-09-16 | Novatome | DEVICE FOR PRODUCING STEAM BY EXCHANGING HEAT BETWEEN A LIQUID-COOLED METAL AND FOOD WATER COMPRISING SEVERAL INTERFACES METAL LIQUID-NEUTRAL GAS |
| JPS63198899A (en) * | 1987-02-13 | 1988-08-17 | 動力炉・核燃料開発事業団 | Method of processing radioactive waste liquor |
| SU1505306A1 (en) * | 1988-01-05 | 1992-06-07 | Предприятие П/Я В-8844 | Method of retreating radio-active alkali metals |
| JPH0777600A (en) * | 1993-09-09 | 1995-03-20 | Kawasaki Heavy Ind Ltd | Recovery system of sodium contained in gas and operating method thereof |
| JPH11258394A (en) * | 1998-03-16 | 1999-09-24 | Mitsubishi Heavy Ind Ltd | Method and device for removing residual sodium |
| JP2002055196A (en) * | 2000-08-09 | 2002-02-20 | Toshiba Corp | Method for disposal of radioactive waste |
| WO2005021807A2 (en) * | 2003-09-02 | 2005-03-10 | International Titanium Powder, Llc. | Separtion system, method and apparatus |
| US6919061B1 (en) * | 2002-05-22 | 2005-07-19 | The United States Of America As Represented By The United States Department Of Energy | In-situ method for treating residual sodium |
| CN1945120A (en) * | 2006-11-21 | 2007-04-11 | 中国原子能科学研究院 | Method for destroying waste sodium, potassium and sodium-potassium alloy |
| CN101197200A (en) * | 2007-12-29 | 2008-06-11 | 中国原子能科学研究院 | Sodium-potassium alloy filling method and device |
| CN101231897A (en) * | 2007-12-11 | 2008-07-30 | 中国原子能科学研究院 | Method for disassembling pipeline filled with liquid sodium-potassium alloy |
| CN201126722Y (en) * | 2007-12-11 | 2008-10-01 | 中国原子能科学研究院 | System for filling and discharging natrium for main container of natrium cold fast reactor |
| CN201126721Y (en) * | 2007-12-11 | 2008-10-01 | 中国原子能科学研究院 | System for filling and discharging natrium for main technique system of natrium cold fast reactor |
| CN205104243U (en) * | 2015-11-10 | 2016-03-23 | 大亚湾核电运营管理有限责任公司 | Stifled isolation structure of online ice of nuclear power station pipeline |
-
2021
- 2021-03-19 CN CN202110295332.7A patent/CN115116638B/en active Active
Patent Citations (16)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1035330A (en) * | 1962-12-28 | 1966-07-06 | Nihon Genshiryoku Kenkyujo | Process and apparatus for treating solid radioactive wastes |
| US3808141A (en) * | 1969-09-17 | 1974-04-30 | Commissariat Energie Atomique | Process for dissolving sodium,potassium and their alloys |
| FR2523268A1 (en) * | 1982-03-11 | 1983-09-16 | Novatome | DEVICE FOR PRODUCING STEAM BY EXCHANGING HEAT BETWEEN A LIQUID-COOLED METAL AND FOOD WATER COMPRISING SEVERAL INTERFACES METAL LIQUID-NEUTRAL GAS |
| JPS63198899A (en) * | 1987-02-13 | 1988-08-17 | 動力炉・核燃料開発事業団 | Method of processing radioactive waste liquor |
| SU1505306A1 (en) * | 1988-01-05 | 1992-06-07 | Предприятие П/Я В-8844 | Method of retreating radio-active alkali metals |
| JPH0777600A (en) * | 1993-09-09 | 1995-03-20 | Kawasaki Heavy Ind Ltd | Recovery system of sodium contained in gas and operating method thereof |
| JPH11258394A (en) * | 1998-03-16 | 1999-09-24 | Mitsubishi Heavy Ind Ltd | Method and device for removing residual sodium |
| JP2002055196A (en) * | 2000-08-09 | 2002-02-20 | Toshiba Corp | Method for disposal of radioactive waste |
| US6919061B1 (en) * | 2002-05-22 | 2005-07-19 | The United States Of America As Represented By The United States Department Of Energy | In-situ method for treating residual sodium |
| WO2005021807A2 (en) * | 2003-09-02 | 2005-03-10 | International Titanium Powder, Llc. | Separtion system, method and apparatus |
| CN1945120A (en) * | 2006-11-21 | 2007-04-11 | 中国原子能科学研究院 | Method for destroying waste sodium, potassium and sodium-potassium alloy |
| CN101231897A (en) * | 2007-12-11 | 2008-07-30 | 中国原子能科学研究院 | Method for disassembling pipeline filled with liquid sodium-potassium alloy |
| CN201126722Y (en) * | 2007-12-11 | 2008-10-01 | 中国原子能科学研究院 | System for filling and discharging natrium for main container of natrium cold fast reactor |
| CN201126721Y (en) * | 2007-12-11 | 2008-10-01 | 中国原子能科学研究院 | System for filling and discharging natrium for main technique system of natrium cold fast reactor |
| CN101197200A (en) * | 2007-12-29 | 2008-06-11 | 中国原子能科学研究院 | Sodium-potassium alloy filling method and device |
| CN205104243U (en) * | 2015-11-10 | 2016-03-23 | 大亚湾核电运营管理有限责任公司 | Stifled isolation structure of online ice of nuclear power station pipeline |
Non-Patent Citations (10)
| Title |
|---|
| INTERNATIONAL WORKING GROUP ON FAST REACTORS: "SODIUM REMOVAL AND DISPOSAL FROM LMFRS IN NOMAL OPERATION AND IN THE FRAMEWORKK OF DECOMMISSIONING", INTERATIONAL ATOMIC ENERGY AGENCY * |
| KARL SHULER: "Decommissioning Sodium Dump Tanks", WM2015 CONFERENCE * |
| O.J.FOUST: "Sodium-NaK Engineering Handbook", SODIUM-NAK ENGINEERING HANDBOOK, pages 132 * |
| W. F.BREHM: "REMOVAL OF RETIRED ALKALI METAL TEST SYSTEMS", WM\'03 CONFERENCE * |
| 中华人民共和国住房和城乡建设部: "建筑拆除工程安全技术规范", 建筑拆除工程安全技术规范, pages 1 - 4 * |
| 刘绩伟;: "液态钠热工水力实验装置的退役处理", 产业与科技论坛, no. 09 * |
| 张勇: "建筑物拆除作业的安全技术", 工业安全与环保, no. 12 * |
| 王荣东等: "CSFR一回路冷阱更换过程中的钠钾合金灌装", 原子能科学技术, vol. 49, no. 7 * |
| 石文涛;杜海鸥;王国芝;王荣东;: "钠管道冷冻封堵作业耗时和作业长度最低限值的计算分析", 产业与科技论坛, no. 14 * |
| 谢淳;赵迅;刘继伟;李煦;李君瑜;禹春利;: "快堆钠设备清洗方法综述", 核科学与工程, no. 02 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN115116638B (en) | 2023-10-20 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN206105044U (en) | Pipeline under pressure does not stop production and bumps a mouthful open structure | |
| CN115116638A (en) | Sodium-potassium alloy coolant pipeline system dismantling and post-processing method | |
| CN205644203U (en) | A safety monitoring system for supercritical water oxidation device | |
| CN104197776B (en) | A kind of explosion-proof cleaning equipment of civil aircraft fuel oil and lubricating oil heat exchanger | |
| CN107723011A (en) | A kind of method that online Water Cutting of negative pressure coal gas system pulls hole | |
| CN213983015U (en) | Tritium-containing heavy water conveying device | |
| CN207525262U (en) | A kind of Iron Works cooling body | |
| CN209042412U (en) | A kind of device preventing dangerous waste incineration waste heat boiler coking | |
| CN211802674U (en) | Online closed cleaning and detecting system for flame arrester | |
| CN207486844U (en) | A kind of fire inspection cooling wind pipeline | |
| CN114028886A (en) | Recovery system and method for scattered flue gas in liquid sulfur loading process | |
| CN112503397A (en) | Tritium-containing heavy water conveying device | |
| CN208332777U (en) | Pre- anti-icing stifled system for cold-hot integrated equipment | |
| CN219630673U (en) | Airtight recovery system of liquid hydrocarbon water cutter export | |
| CN112802618A (en) | Ice plug isolation process for nuclear power explosion valve | |
| CN110682236A (en) | Ice plug jacket device for metal surface sealing joint maintenance operation | |
| CN219001815U (en) | Combustion emergency disposal box for dangerous goods | |
| CN206169444U (en) | Novel steam conduit welding device | |
| CN110459332A (en) | Nuclear power station fire_fighting pipe network system and nuclear power station fire_fighting pipe network method for on-line optimization | |
| CN217239060U (en) | Temporary storage device is collected to radioactive sodium waste | |
| CN109100176A (en) | A kind of sampling system | |
| CN204492758U (en) | A kind of Petroleum Production on-the-spot oil pipe thorn cleaning device | |
| CN220749848U (en) | Leakage-proof gas drainer | |
| CN208967208U (en) | A kind of device avoiding water hammer damage for space division vaporizer steam valve | |
| CN218654405U (en) | Blockage cleaning device for condensate return pipe |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |