Process for the treatment of radioactive waste incineration ash

Abstract

The application discloses a kind of radioactive waste incineration ash processing technology, including moving assembly;And, setting in the receiving assembly of the moving assembly inner wall;And, setting in the stirring assembly of the moving assembly inner wall, including stirrer and setting in the mortar hopper of the stirrer bottom;Wherein, the position of the moving assembly can be changed, to make stirrer in different positions to stir cement, and pour cement into nuclear waste by the mortar hopper.The movable radioactive waste incineration ash processing technology is free from the dependence of traditional fixed device on work scene, and can flexibly meet the remote fixed needs of radioactive solid waste.

Description

Technical Field

[0001] This invention relates to the field of nuclear waste treatment, and in particular to a process for treating radioactive waste incineration ash. Background Technology

[0002] Existing radioactive incineration ash cement solidification technology mainly involves mixing radioactive incineration ash with cement and other fixatives in a certain proportion, stirring to form an ash slurry, and then pouring it into a container to harden it. This achieves the fixation and containment of radioactive materials, thus stabilizing and rendering the material harmless. This technology aims to use the cement's binding effect to encapsulate the radioactive incineration ash within the solidified body, reducing the leaching rate of radionuclides and facilitating subsequent temporary storage, transportation, and final disposal.

[0003] However, most existing cement fixing equipment is a fixed structure, usually designed and installed near waste storage or hot chambers, which cannot be moved flexibly and cannot meet the needs of remote fixing of radioactive solid waste. It is also highly dependent on the treatment scenario. Summary of the Invention

[0004] Therefore, the technical problem to be solved by the present invention is to provide a mobile radioactive waste incineration ash treatment process.

[0005] The above-mentioned technical problems are solved by the following technical solution: This invention proposes a process for treating radioactive waste incineration ash, which includes,

[0006] The incineration ash produced by the mobile incineration unit is loaded into a steel drum and sealed. After passing the inspection, it is transported to the overpressure section for overpressure treatment to obtain compressed cakes. The compressed cakes are then loaded into a steel box and transported to the curing unit.

[0007] The solidification device is used to mix dry cement with water to form cement slurry, which is then used to cast the steel box.

[0008] After the pouring is completed, the steel box will be removed for curing and temporary storage. After curing, it will be transferred to a designated disposal site for storage.

[0009] In a preferred embodiment of the radioactive waste incineration ash treatment process of the present invention: the solidification device includes...

[0010] Mobile components that can be moved by transport equipment; and,

[0011] A storage component disposed on the inner wall of the movable component; and...

[0012] The mixing assembly disposed on the inner wall of the movable component includes a mixer and a mortar hopper disposed at the bottom of the mixer; wherein,

[0013] The position of the moving component can be changed so that the mixer can mix cement at different positions and pour the cement into the nuclear waste through the mortar hopper.

[0014] In a preferred embodiment of the radioactive waste incineration ash treatment process of the present invention: the moving component includes a box, a baffle disposed on the inner wall of the box, and a double door disposed on one side of the box.

[0015] In a preferred embodiment of the radioactive waste incineration ash treatment process of the present invention: the receiving component includes a suspension arm, a storage hopper disposed on one side of the box, a vibrator disposed on one side of the storage hopper, and a screw conveyor disposed at the bottom of the storage hopper.

[0016] In a preferred embodiment of the radioactive waste incineration ash treatment process of the present invention: the bottom of the suspension arm is connected to the bottom of the box, and one end of the screw conveyor is connected to one side of the mixer.

[0017] In a preferred embodiment of the radioactive waste incineration ash treatment process of the present invention: the mixer is disposed on the inner wall of the box, and a cleaning machine is disposed on one side of the box.

[0018] In a preferred embodiment of the radioactive waste incineration ash treatment process of the present invention: a water tank is provided on one side of the box body, the cleaning machine is connected to the water tank, and one side of the cleaning machine is connected to the outer wall of the mixer.

[0019] In a preferred embodiment of the radioactive waste incineration ash treatment process of the present invention: an operating platform for operating the stirring component is provided on one side of the box. When the operating platform controls the stirring component to stir, the cleaning machine draws clean water from the water tank and delivers it into the stirring component.

[0020] In a preferred embodiment of the radioactive waste incineration ash treatment process of the present invention: a dust collector capable of recovering ash is provided on one side of the storage hopper, and the dust collector can absorb dust in the air when cement dry material is conveyed to the storage hopper.

[0021] In a preferred embodiment of the radioactive waste incineration ash treatment process of the present invention: one side of the dust collector is connected to one side of the baffle. When cement dry material is conveyed to the storage hopper, the baffle will prevent dust from spreading to other areas.

[0022] The beneficial effects of this invention are that, through the mobile radioactive waste incineration ash treatment process, it eliminates the dependence of traditional fixed equipment on the operating environment and can flexibly meet the needs of remote fixation of radioactive solid waste.

[0023] Meanwhile, the device integrates functions such as storage, stirring, and dust removal, and, in conjunction with a continuous overpressure treatment process, improves operational efficiency and the safety of the working environment, solving the problems of poor process connection and low equipment integration in existing technologies. Attached Figure Description

[0024] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings of the embodiments of the present invention will be briefly described below. Obviously, the drawings described below only relate to some embodiments of the present invention and are not intended to limit the present invention. Wherein:

[0025] Figure 1 A structural diagram of a radioactive waste incineration ash treatment process is shown.

[0026] Figure 2 A top view of a radioactive waste incineration ash treatment process is shown;

[0027] Figure 3 A flowchart of a radioactive waste incineration ash treatment process is shown.

[0028] Figure 4 A flowchart of a radioactive waste incineration ash treatment process is shown. Detailed Implementation

[0029] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0030] The terminology used in this invention is that which is currently widely used in the art in consideration of the function of the invention; however, these terms may vary according to the intent of those skilled in the art, precedent, or new technology in the art. Furthermore, specific terms may be chosen by the applicant, and in such cases, their detailed meanings will be described in the detailed description of the invention. Therefore, the terms used in this specification should not be construed as simple names, but rather based on their meanings and the overall description of the invention.

[0031] Reference Figures 1-3 This embodiment provides a radioactive waste incineration ash treatment process, including a solidification device, including a movable component 100 that can be moved by a transport device; a receiving component 200 disposed on the inner wall of the movable component 100; and a mixing component 300 disposed on the inner wall of the movable component 100, including a mixer 301 and a slurry hopper 302 disposed at the bottom of the mixer 301; wherein, the position of the movable component 100 can be changed so that the mixer 301 can mix cement at different positions, and the cement can be poured into the nuclear waste through the slurry hopper 302.

[0032] The mobile component 100 can be moved as a whole by transportation equipment such as trailers or forklifts. The dry cement material is then pre-processed by the storage component 200 and then transported to the mixing component 300. The dry cement material and water are mixed by the mixer 301, and finally the cement slurry is poured into the nuclear waste through the mortar hopper 302.

[0033] It should be noted that the housing 101 of the mobile component 100 is made of Q355B low-alloy high-strength structural steel, and the surface is coated with a 2mm thick epoxy resin anti-corrosion coating, which can withstand long-term corrosion in a radioactive environment and has the ability to resist radiation penetration and acid and alkali corrosion.

[0034] As an alternative embodiment, the method of mixing dry cement is specifically described.

[0035] The mobile component 100 includes a housing 101, a baffle 102 disposed on the inner wall of the housing 101, and a double door 103 disposed on one side of the housing 101. The housing 101 is a square steel structure housing, which is divided into a feeding area, a mixing area, and an operating area, providing installation space for each component and providing protection.

[0036] It should be noted that the baffle 102 is vertically installed on the inner wall of the box to separate different functional areas, such as isolating the feeding area from the mixing area. It can also be used as a support point for installing other facilities. Two baffles 102 are installed on the inner wall of the box. The baffles 102 are made of steel and are vertically welded to the inner wall of the box. The surface is galvanized. They not only achieve physical isolation between the feeding area and the mixing area, but also serve as the installation reference for the dust collector 205 and the operating table 400.

[0037] It should be noted that the double door 103 is located on one side of the enclosure 101 and adopts a sealed design. The contact area between the door frame and the door leaf is milled and equipped with fluororubber sealing strips. In order to ensure the internal safety of the curing device, a combination lock is usually installed inside the double door 103. When actually operating the curing device, the double door 103 needs to be unlocked to enter the curing device. This not only ensures the internal safety of the curing device, but also reduces the risk of radioactive material leakage during operation.

[0038] The storage component 200 includes a suspension arm 201, a storage hopper 202 located on one side of the box 101, a vibrator 203 located on one side of the storage hopper 202, and a screw conveyor 204 located at the bottom of the storage hopper 202. The bottom of the suspension arm 201 is welded and fixed to the bottom of the box 101, and the top is equipped with an electric hoist connected to a hook by a wire rope, which can lift bagged dry cement into the storage hopper 202, realizing automated feeding and reducing manual contact.

[0039] It should be noted that after the suspended arm 201 transports the dry cement material into the container 101, the dry cement material packaging bag needs to be cut open with a cross cutter, and then the dry cement material is poured into the storage hopper 202. The storage hopper 202 is set on one side of the container 101 and is used to temporarily store the dry cement material. Its inner wall is coated with a wear-resistant coating to prevent the dry material from sticking together. The vibrator 203 set on one side will prevent the dry cement material from clumping and blocking in the hopper through high-frequency vibration. At the same time, the screw conveyor 204 is equipped with a screw. When the screw rotates, it will drive the dry cement material to move.

[0040] It should be noted that during the transportation of dry cement materials, the dust collector 205 uses a model MC-Ⅱ pulse bag dust collector, which will adsorb the cement dust generated during the feeding process and prevent the dust from spreading and polluting the working environment.

[0041] The bottom of the suspension arm 201 is connected to the bottom of the box 101, and one end of the screw conveyor 204 is connected to one side of the mixer 301.

[0042] The mixer 301 is installed on the inner wall of the box 101. A washing machine 303 is installed on one side of the box 101, and a water tank 304 is installed on the other side of the box 101. The washing machine 303 and the water tank 304 are connected to each other. One side of the washing machine 303 is connected to the outer wall of the mixer 301. The mixer 301 is installed in the mixing zone on the inner wall of the box and adopts a dual-shaft mixing design. The mixing blades are made of wear-resistant alloy material, which can cope with the high hardness of cement dry materials. The uniformity of the slurry is ensured by switching between high and low speeds (low speed mixing, high speed homogenization).

[0043] It should be noted that the mortar hopper 302 is located at the bottom of the mixer 301, and the bottom is connected to the screw pump and the pouring pipe. It is used to temporarily store the cement slurry after mixing, and the slurry is precisely injected into the gap of the compression cake in the steel box by the pressure of the screw pump.

[0044] It should be noted that the cleaning machine 303 is connected to the water tank 304 through a pipe, and its outlet is located in the inner wall of the mixer 301. After the cement slurry is poured, high-pressure clean water can be sprayed out to rinse the residual slurry and avoid equipment blockage. At the same time, clean water will be continuously delivered during the mixing process to mix with the dry cement to form cement slurry.

[0045] It should be noted that the water tank 304 stores clean water for stirring and cleaning, and is equipped with a liquid level sensor. When the liquid level is low, an alarm will be issued through the control panel 400 to prompt the replenishment of water.

[0046] Specifically, after the dry cement material enters the mixer 301, the washing machine 303 will inject water into the mixer 301. The mixer 301 will slowly stir the dry cement material. After enough clean water is injected, the mixer 301 will speed up the stirring speed. After stirring for a certain period of time, the cement slurry will form. The mixer 301 will slow down the stirring speed again, and the washing machine 303 will also stop injecting water. Finally, the cement slurry will be poured into the nuclear waste through the mortar hopper 302.

[0047] A control panel 400 for operating the mixing component 300 is provided on one side of the housing 101. When the control panel 400 controls the mixing component 300 to mix, the cleaning machine 303 draws clean water from the water tank 304 and delivers it into the mixing component 300. A dust collector 205 for recovering dust is provided on one side of the storage hopper 202. When cement dry material is delivered to the storage hopper 202, the dust collector 205 can absorb dust in the air. One side of the dust collector 205 is connected to one side of the baffle 102. When cement dry material is delivered to the storage hopper 202, the baffle 102 will prevent dust from spreading to other areas. The control panel 400 integrates control buttons, display screen and parameter adjustment knobs for each component. It can monitor parameters such as the material level in the storage hopper, the speed of the mixer, and the liquid level in the water tank in real time, and realize automated operation through PLC program, such as the linkage start of the screw conveyor and the mixer, and the timed cleaning of the cleaning machine.

[0048] Reference Figure 4 This embodiment provides a process for treating radioactive waste incineration ash, including the following steps:

[0049] The incineration ash produced by the mobile incineration unit is loaded into steel drums and sealed. After passing inspection, it is transported to the overpressure section for overpressure treatment to obtain compressed cakes. The compressed cakes are then loaded into steel boxes and transported to the radioactive waste incineration ash treatment process. Before processing the incineration ash, it needs to be loaded into special aramid filter bags, with each bag having a load of ≤50kg. The filter bags are then sealed using a heat sealer and placed into a 200L steel drum. The steel drum lid is then fixed to the drum with eight M16 bolts to form a sealed waste bag. The surface dose rate of the waste bag is then measured using an FH40G radiation dosimeter (limit ≤2μSv / h), and the sealing is checked by a water pressure test. Unqualified products are shielded with a 3mm thick lead plate or cleaned with a 5% nitric acid solution and then retested. The waste bag is then sent to the overpressure section, where a Y32-315 four-column hydraulic press is used to apply axial pressure to the steel drum, compressing the incineration ash into compressed cakes.

[0050] The solidification device is used to mix dry cement and water to form cement slurry, which is then used to pour steel boxes. During the solidification process, the dry cement is hoisted to the storage hopper by the suspension arm, the vibrator assists in feeding, and the dust collector removes dust simultaneously. Then, the screw conveyor transports the dry cement to the mixer, and the compressed cake is hoisted to the mortar hopper 302 directly below by the suspension arm. It is then placed in a steel box. Subsequently, silicate cement is hoisted to the storage hopper 202 by the suspension arm 201, the vibrator 203 operates at a frequency of 50Hz, and the dust collector 205 starts simultaneously.

[0051] It should be noted that during cement mixing, the cleaning machine supplies a set amount of clean water to the mixer. The mixer mixes the dry cement with the clean water to form a cement slurry. The cement slurry is then poured into the steel tank through the slurry hopper and the conveying pump. After the gravity sensor in the storage hopper 202 detects the preset amount, the screw conveyor 204 transports the dry cement to the mixer 301. At the same time, the water tank 304 is injected with 67L of clean water through the cleaning machine 303. The mixer first mixes at a low speed of 30r / min for 2 minutes. After the clean water is poured in, it switches to a high speed of 180r / min for 8 minutes to form a cement slurry with a fluidity of 180±5mm. Then, it mixes at a low speed of 20r / min, opens the gate valve and starts the conveying pump, and injects the slurry into the steel tank through a φ80mm wear-resistant pipe.

[0052] After the pouring is completed, the steel box is removed for curing and temporary storage. After curing, it is transferred to a designated disposal site for storage. After the pouring is completed, the mixer and pipeline are washed with a 303 cleaning machine at a pressure of 300 bar for 3 minutes. The wastewater is collected in an HDPE anti-corrosion waste liquid tank through a φ100mm sewage pipe. After the steel box is removed, it is placed in the curing area. After curing for 28 days, the compressive strength of the solidified body is tested. If it passes the test, it is transferred to the radioactive waste disposal site.

[0053] Finally, it should be noted that the methods and devices described in detail above are merely embodiments, and those skilled in the art can modify these embodiments in different ways as long as they do not depart from the scope of the present invention.

Claims

1. A process for treating radioactive waste incineration ash, characterized in that: include, The incineration ash produced by the mobile incineration unit is loaded into a steel drum and sealed. After passing the inspection, it is transported to the overpressure section for overpressure treatment to obtain compressed cakes. The compressed cakes are then loaded into a steel box and transported to the curing unit. The solidification device is used to mix dry cement with water to form cement slurry, and then the cement slurry is used to cast the steel box. After the pouring is completed, the steel box will be removed for curing and temporary storage. After curing, it will be transferred to a designated disposal site for storage.

2. The radioactive waste incineration ash treatment process according to claim 1, characterized in that: The curing device includes, A movable component (100) that can be moved by transport equipment; and, A storage component (200) disposed on the inner wall of the movable component (100); and, The mixing assembly (300) disposed on the inner wall of the moving assembly (100) includes a mixer (301) and a mortar hopper (302) disposed at the bottom of the mixer (301); wherein, The position of the movable component (100) can be changed so that the mixer (301) can mix cement at different positions and pour cement into nuclear waste through the mortar hopper (302).

3. The radioactive waste incineration ash treatment process according to claim 2, characterized in that: The moving component (100) includes a housing (101), a baffle (102) disposed on the inner wall of the housing (101), and a double door (103) disposed on one side of the housing (101).

4. The radioactive waste incineration ash treatment process according to claim 3, characterized in that: The storage assembly (200) includes a suspension arm (201), a storage hopper (202) disposed on one side of the box (101), a vibrator (203) disposed on one side of the storage hopper (202), and a screw conveyor (204) disposed at the bottom of the storage hopper (202).

5. The radioactive waste incineration ash treatment process according to claim 4, characterized in that: The bottom of the suspension arm (201) is connected to the bottom of the box (101), and one end of the screw conveyor (204) is connected to one side of the mixer (301).

6. The radioactive waste incineration ash treatment process according to claim 5, characterized in that: The mixer (301) is disposed on the inner wall of the box (101), and a cleaning machine (303) is disposed on one side of the box (101).

7. The radioactive waste incineration ash treatment process according to claim 6, characterized in that: A water tank (304) is provided on one side of the housing (101), and the cleaning machine (303) is connected to the water tank (304). One side of the cleaning machine (303) is connected to the outer wall of the mixer (301).

8. The radioactive waste incineration ash treatment process according to claim 7, characterized in that: The box (101) is provided with an operating table (400) for operating the stirring assembly (300) on one side. When the operating table (400) controls the stirring assembly (300) to stir, the cleaning machine (303) draws clean water from the water tank (304) and delivers it into the stirring assembly (300).

9. The radioactive waste incineration ash treatment process according to claim 8, characterized in that: A dust collector (205) is provided on one side of the storage hopper (202) to collect dust. When cement dry material is conveyed to the storage hopper (202), the dust collector (205) can absorb dust in the air.

10. The radioactive waste incineration ash treatment process according to claim 9, characterized in that: The dust collector (205) is connected to the baffle (102) on one side. When cement dry material is conveyed to the storage hopper (202), the baffle (102) will prevent dust from spreading to other areas.

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