An automatic metering and neutralizing device and method

Abstract

The present invention belongs to the field of radioactive waste treatment in nuclear power plants, and particularly relates to an automatic metering and neutralizing device and method. The waste packages after the "evaporation and drying" technology contain strongly corrosive substances, which do not meet the requirements for the harmless treatment and disposal of radioactive waste to ensure permanent safety. The present invention includes an automatic metering unit and an automatic neutralizing unit, so that the radioactive concentrated waste liquid first enters the metering and neutralizing tank for metering before drying in the barrel, and then according to the metering result and the PH automatic measurement and dosing controller, calculates the amount of the added medicament, controls the type of the medicament required for neutralization, and uses a stirring paddle for stirring to effectively neutralize the radioactive concentrated waste liquid in the metering and neutralizing tank, and then conducts drying treatment. The present invention realizes the automatic control and remote monitoring of operations in the radioactive area, and moreover ensures that the treated radioactive waste packages do not contain strongly corrosive substances, meeting the requirements for waste package disposal and national standards.

Description

Technical Field

[0001] The present invention belongs to the field of radioactive trinity waste treatment in nuclear power plants, and particularly relates to an automatic metering and neutralization device and method. Background Art

[0002] During the normal operation of nuclear facilities, a large amount of radioactive waste liquid will inevitably be generated. These waste liquids are treated through collection, storage decay, ion exchange, filtration, etc. After the treated waste liquid is monitored and qualified, it is discharged. The unqualified waste liquid is treated by evaporation. However, the concentrated sediment generated after evaporation treatment (collectively referred to as radioactive concentrated waste liquid) contains a large amount of radioactive substances. Generally, the cement solidification treatment process is used to solidify it into a solid body for solid waste treatment. Although the traditional cement solidification process is simple, the volume increase ratio is relatively large. In order to minimize radioactive waste, in recent years, the "evaporation and drying" technology has been adopted to evaporate the radioactive concentrated waste liquid generated by nuclear facilities. This process collects the radioactive concentrated waste liquid generated during the evaporation treatment of the waste liquid in a concentrated waste liquid receiving tank, and then directly transports the radioactive concentrated waste liquid to a metal barrel in a barrel dryer through a concentrated waste liquid transfer pump. The concentrated waste liquid in the barrel is dried by heating the metal barrel. The concentrated waste liquid in the barrel is dried into a solid substance. The dried barrel can be super-compacted, and then the barrel cake is fixed and temporarily stored in a metal barrel, or it can be directly fixed in a high-integrity concrete container and sent to the final disposal site for treatment.

[0003] This treatment process has the following problems:

[0004] Since the radioactive concentrated waste liquid generated by nuclear facilities contains components such as NaOH and boric acid, the waste package after this treatment process contains strongly corrosive substances, which does not meet the requirements for the harmless treatment and disposal of radioactive waste to ensure permanent safety.

[0005] The waste package after this treatment process contains strongly corrosive substances, which does not meet the requirement in the national standard "Safety Regulations for the Near-Surface Disposal of Low- and Medium-Level Radioactive Solid Wastes" GB9132-2018 that the waste package should not contain strongly corrosive substances.

[0006] To solve the above problems, a device needs to be designed so that the waste package generated after the evaporation and drying of radioactive concentrated waste liquid does not contain strongly corrosive substances and meets the requirements for radioactive waste disposal. Summary of the Invention

[0007] Objective:

[0008] The present invention designs an automatic metering and neutralization device and method, enabling the radioactive concentrated waste liquid generated by nuclear facilities to be first metered, and then a neutralization reaction is carried out on the radioactive concentrated waste liquid according to the metering results using the principles of acid and alkali neutralization. The amounts of acid and alkali required for neutralization are automatically measured based on the pH value and automatically calculated. The injection amounts of acid and alkali are controlled through feedback interlock signals, and then the neutralized radioactive concentrated waste liquid is sent into the barrel dryer for evaporation and drying treatment, ensuring that the radioactive waste package does not contain strongly corrosive substances, not only meeting the requirements for the final disposal of the waste package, but also realizing the reduction, harmless treatment and disposal of radioactive waste, and ensuring the goal requirements of permanent safety.

[0009] Technical solution:

[0010] An automatic metering and neutralization device includes an automatic metering unit and an automatic neutralization unit. The automatic metering unit includes a metering and neutralization tank inlet valve, a metering and neutralization tank, a metering and neutralization tank outlet valve, a stirring paddle, a stirring motor, a metering and neutralization tank exhaust filter, an exhaust valve, a liquid level gauge, and a pressure gauge; the metering and neutralization tank inlet valve is connected to the metering and neutralization tank in a flange form through a pipeline, the bottom of the metering and neutralization tank is connected to the metering and neutralization tank outlet valve through a pipeline, and the metering and neutralization tank outlet valve is connected to the inlet valve of the barrel dryer through a pipeline; the top of the metering and neutralization tank is connected to the metering and neutralization tank exhaust filter in a flange form through a pipeline, the metering and neutralization tank exhaust filter is connected to the exhaust valve through a pipeline, the exhaust valve is connected to the plant equipment exhaust system through a pipeline, the top of the metering and neutralization tank is connected to the liquid level gauge and the pressure gauge in a flange form through a pipeline, a stirring motor is installed on the top of the metering and neutralization tank and is connected to the stirring paddle through a torsion bar.

[0011] The automatic neutralization unit includes an acid liquid storage tank, an alkali liquid storage tank, a dosing pump, an acid liquid storage tank outlet valve, an alkali liquid storage tank outlet valve, a dosing pump inlet valve, a dosing pump outlet valve, an on-line pH measuring meter, a flange, a pH automatic measurement and dosing controller, a remote control operation console, and a flow meter; the top of the metering and neutralization tank is connected to the dosing pump outlet valve in a flange form through a pipeline, a flow meter is installed on the intermediate pipeline, the dosing pump outlet valve is connected to the dosing pump through a pipeline, the dosing pump is connected to the dosing pump inlet valve through a pipeline, the dosing pump inlet valve is connected to the acid liquid storage tank outlet valve and the alkali liquid storage tank outlet valve respectively through a pipeline, and the acid liquid storage tank outlet valve extends into the bottom of the acid liquid storage tank through a pipeline. The alkali liquid storage tank outlet valve extends into the bottom of the alkali liquid storage tank through a pipeline, the on-line pH measuring meter is installed inside the metering and neutralization tank in a flange form and is connected to the pH automatic measurement and dosing controller through a measuring line. Among them, the instrument control signals of the acid liquid storage tank outlet valve, the alkali liquid storage tank outlet valve, the dosing pump inlet valve, the dosing pump outlet valve, the dosing pump, the flow meter, and the liquid level gauge are connected to the pH automatic measurement and dosing controller through cables, and the pH automatic measurement and dosing controller is connected to the remote control operation console through a cable.

[0012] An automatic metering and neutralization method, including Step 1: transporting radioactive concentrated waste liquid to a metering and neutralization tank; Step 2: neutralizing the radioactive concentrated waste liquid; Step 3: evaporating and drying the radioactive concentrated waste liquid.

[0013] Step 1: Transporting radioactive concentrated waste liquid to a metering and neutralization tank, including the following steps:

[0014] (1) After the radioactive waste liquid is evaporated by the evaporator of the radioactive waste liquid treatment system, the generated concentrated waste liquid is transported to the concentrated waste liquid receiving tank for storage by the concentrated waste pump. After temporary storage and decay, the outlet valve of the concentrated waste liquid receiving tank, the inlet valve of the concentrated waste liquid transport pump, the inlet valve of the metering and neutralization tank, and the exhaust valve are opened;

[0015] (2) Start the concentrated waste liquid transport pump to transport the radioactive concentrated waste liquid to the metering and neutralization tank. When the liquid level reaches 70% of the effective volume of the metering and neutralization tank, the concentrated waste liquid transport pump and the inlet valve of the metering and neutralization tank are automatically shut down through interlock control; close the outlet valve of the concentrated waste liquid receiving tank and the inlet valve of the concentrated waste liquid transport pump for radioactive concentrated waste liquid transport.

[0016] Step 2: Neutralizing the radioactive concentrated waste liquid, including the following steps:

[0017] (1) Start the PH automatic measurement and dosing controller. The online PH meter measures the PH value of the radioactive concentrated waste liquid in the metering and neutralization tank, and the volume of the radioactive concentrated waste liquid in the metering and neutralization tank is obtained through the liquid level meter;

[0018] (2) Start the stirring paddle motor to make the stirring paddle in a working state;

[0019] (3) The PH automatic measurement and dosing controller determines the reagent to be neutralized according to the PH value and volume of the radioactive concentrated waste liquid, calculates the amount of reagent to be added, and performs the neutralization dosing operation through remote control commands;

[0020] (4) If the system determines that the reagent to be added is an acidic solution, the system opens the outlet valve of the acid storage tank, the inlet valve of the dosing pump, and the outlet valve of the dosing pump, then starts the dosing pump. When the flow meter measures the set amount, the system shuts down the dosing pump and closes the outlet valve, the inlet valve of the dosing pump, and the outlet valve of the dosing pump;

[0021] (5) If the system determines that the reagent to be added is an alkaline solution, the system opens the outlet valve of the acid storage tank, the inlet valve of the dosing pump, and the outlet valve of the dosing pump, then starts the dosing pump. When the flow meter measures the set amount or the measured value of the liquid level meter reaches 90% of the effective volume of the metering and neutralization tank, the system shuts down the dosing pump and closes the outlet valve of the acid storage tank, the inlet valve of the dosing pump, and the outlet valve of the dosing pump;

[0022] (6) After the medicament is added to the metering neutralization tank, a neutralization reaction takes place in the tank. After the neutralization reaction ends after a period of time, remotely check the online pH meter to obtain the measured value. If it reaches 6.5 - 7.5, the neutralization reaction ends;

[0023] (7) If the measured value obtained by the online pH meter is less than 6.5 or greater than 7.5, the system executes according to steps 3 and 4;

[0024] (8) Turn off the pH automatic measurement and dosing controller.

[0025] Step 3: Evaporation and drying of radioactive concentrated waste liquid, including the following steps:

[0026] (1) Place the waste barrel in the in-barrel dryer through the roller path;

[0027] (2) Open the outlet valve of the metering neutralization tank and the inlet valve of the in-barrel dryer, and drain the waste liquid in the metering neutralization tank into the in-barrel dryer. After the liquid level in the in-barrel dryer reaches 80%, close the outlet valve of the metering neutralization tank and the inlet valve of the in-barrel dryer through interlocking;

[0028] (3) Open the inlet valve of the condenser, start the in-barrel dryer for evaporation and drying. At this time, the steam passes through the steam-water separation filter and enters the condenser for condensation. After the condensed water generated by condensation reaches a certain liquid level height, open the inlet valve of the condensate discharge pump, the outlet valve of the condensate discharge pump, and start the condensate discharge pump to discharge it into the special underground water discharge and collection system of the plant. After the discharge is completed, turn off the condensate discharge pump, and close the inlet valve of the condensate discharge pump and the outlet valve of the condensate discharge pump;

[0029] (4) When the liquid level in the condenser no longer rises within a certain period of time, it indicates that the evaporation of the waste liquid in the in-barrel dryer has reached the requirement. At this time, open the outlet valve of the metering neutralization tank and the inlet valve of the in-barrel dryer, and drain the waste liquid in the metering neutralization tank into the in-barrel dryer. After the liquid level in the in-barrel dryer reaches a certain height, close the outlet valve of the metering neutralization tank and the inlet valve of the in-barrel dryer through interlocking, and cycle until the weight of the in-barrel drying device reaches a certain amount or the solid liquid level in the barrel reaches a certain height, then the heating device stops, and the single-barrel evaporation and drying operation is completed;

[0030] (5) Repeat the above steps until all the radioactive concentrated waste liquid in the metering neutralization tank is completely evaporated and dried;

[0031] (6) The waste barrels after evaporation and drying are subjected to subsequent treatment according to the process flow.

[0032] Beneficial effects:

[0033] a) An automatic metering and neutralization device and method of the present invention are characterized in that an automatic metering unit is designed to add corresponding medicaments into the metering and neutralization tank for neutralization, so that the treated waste package does not contain strongly corrosive substances, which not only meets the requirements for the final disposal of the waste package, but also realizes the target requirements of radioactive waste, harmless treatment, disposal, and ensuring permanent safety, and has important reference value for the design of radioactive waste treatment systems and waste treatment ideas.

[0034] b) An automatic metering and neutralization device and method of the present invention are characterized in that an automatic neutralization unit is designed to automatically measure the pH value of radioactive concentrated waste liquid in the metering and neutralization tank. Through the calculation and control of the pH automatic measurement and dosing controller, the amount of medicament added is automatically calculated, and the type of medicament required for neutralization is automatically controlled, realizing the automatic control and remote monitoring of operations in the radioactive area and improving the safety of the system.

[0035] c) An automatic metering and neutralization device and method of the present invention are characterized in that a stirring paddle is provided in the metering and neutralization tank, and a stirring motor is provided at the top, which fully ensures the effectiveness of neutralization and improves the reliability of the system.

[0036] d) An automatic metering and neutralization device and method of the present invention are characterized in that a metering and neutralization tank exhaust filter is provided at the top of the metering and neutralization tank, which ensures that the exhaust meets the emission requirements and improves the safety of the system.

[0037] e) An automatic metering and neutralization device and method of the present invention are characterized in that an on-line pH meter is installed inside the metering and neutralization tank in a flange form, and is connected to the pH automatic measurement and dosing controller through a measurement line to realize the automatic measurement and feedback of the pH value. The control of the automatic neutralization unit is automatically controlled by a PLC, and the valves and dosing pumps of the automatic neutralization unit are controlled through interlock control, improving the safety of the system.

[0038] Through optimization, selection and comparison, the present invention determines to use 30% - 60% dilute sulfuric acid as the neutralization medicament for NaOH, which not only ensures the safety of the system, but also solves the problem of treating waste liquid containing NaOH components in radioactive concentrated waste liquid. Description of the Drawings

[0039] Figure 1 It is a schematic flow chart of the invention patent "An automatic metering and neutralization device and method".

[0040] In the figure: 1. Concentrated waste liquid receiving tank; 2. Outlet valve of concentrated waste liquid receiving tank; 3. Inlet valve of concentrated waste liquid transfer pump; 4. Concentrated waste liquid transfer pump; 5. Inlet valve of in-barrel dryer; 6. In-barrel dryer; 7. Steam-water separation filter; 8. Inlet valve of condenser; 9. Condenser; 10. Inlet valve of condensate discharge pump; 11. Condensate discharge pump; 12. Outlet valve of condensate discharge pump; 13. Acid liquid storage tank; 14. Outlet valve of acid liquid storage tank; 15. Alkali liquid storage tank; 16. Outlet valve of alkali liquid storage tank; 17. Inlet valve of dosing pump; 18. Dosing pump; 19. Outlet valve of dosing pump; 20. Inlet valve of metering neutralization tank; 21. Metering neutralization tank; 22. Outlet valve of metering neutralization tank; 23. Agitator paddle; 24. Agitator paddle motor; 25. Exhaust filter of metering neutralization tank; 26. Exhaust valve; 27. Liquid level gauge; 28. Pressure gauge; 29. Online pH measuring instrument; 30. Flange; 31. pH automatic measurement and dosing controller; 32. Remote control operation console; 33. Flowmeter. Detailed implementation mode

[0041] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments.

[0042] The present invention designs an automatic metering and neutralization device and method, which mainly includes an automatic metering unit and an automatic neutralization unit. The main feature is that an automatic metering unit and an automatic neutralization unit are designed between the concentrated waste liquid receiving tank and the in-barrel dryer, so that the radioactive concentrated waste liquid first enters the metering neutralization tank for metering before being dried in the barrel, and then according to the calculation and control of the metering result and the pH automatic measurement and dosing controller, the amount of the added reagent is automatically calculated, the type of the required neutralizing reagent is automatically controlled, and the agitator paddle is used for stirring to effectively neutralize the radioactive concentrated waste liquid in the metering neutralization tank, so that the radioactive concentrated waste liquid remains neutral and no longer contains corrosive substances. Finally, the radioactive concentrated waste liquid is sent into the in-barrel drying device for evaporation and drying treatment, which not only realizes the automatic control and remote monitoring of the operation in the radioactive area, but also ensures that the treated radioactive waste package does not contain strong corrosive substances, meeting the requirements of waste package disposal and national standards.

[0043] The automatic metering unit includes a metering neutralization tank inlet valve 20, a metering neutralization tank 21, a metering neutralization tank outlet valve 22, a stirring paddle 23, a stirring paddle motor 24, a metering neutralization tank exhaust filter 25, an exhaust valve 26, a liquid level gauge 27, a pressure gauge 28 and their pipelines. The outlet of the concentrated waste liquid transfer pump is connected to the metering neutralization tank inlet valve 20 through a pipeline. The metering neutralization tank inlet valve 20 is connected to the metering neutralization tank 21 in a flange form through a pipeline. The bottom of the metering neutralization tank 21 is connected to the metering neutralization tank outlet valve 22 through a pipeline. The metering neutralization tank outlet valve 22 is connected to the inlet valve 5 of the in-barrel dryer through a pipeline. The top of the metering neutralization tank 21 is connected to the metering neutralization tank exhaust filter 25 in a flange form through a pipeline. The metering neutralization tank exhaust filter 25 is connected to the exhaust valve 26 through a pipeline. The exhaust valve 26 is connected to the exhaust system of the plant equipment through a pipeline. The top of the metering neutralization tank 21 is connected to the liquid level gauge 27 and the pressure gauge 28 in a flange form through a pipeline. The stirring paddle motor 24 is installed on the top of the metering neutralization tank 21 and is connected to the stirring paddle 23 through a torsion bar.

[0044] The inlet valve 5 of the in-barrel dryer is connected to the in-barrel dryer 6 through a pipeline and an expansion pipe. The in-barrel dryer 6 is connected to the steam-water separation filter 7 through a pipeline and an expansion pipe. The steam-water separation filter 7 is connected to the condenser inlet valve 8 through a pipeline. The condenser inlet valve 8 is connected to the condenser 9 through a pipeline. The condenser 9 is connected to the condensate discharge pump inlet valve 10 through a pipeline. The condensate discharge pump inlet valve 10 is connected to the condensate discharge pump 11 through a pipeline. The condensate discharge pump 11 is connected to the condensate discharge pump outlet valve 12 through a pipeline.

[0045] The automatic neutralization unit includes an acid storage tank 13, an alkali storage tank 15, a chemical dosing pump 18, an acid storage tank outlet valve 14, an alkali storage tank outlet valve 16, a chemical dosing pump inlet valve 17, a chemical dosing pump outlet valve 19, an on-line pH meter 29, a flange 30, a pH automatic measurement and chemical dosing controller 31, a remote control operation console 32, a flow meter 33 and its pipelines and cable lines. The top of the metering and neutralizing tank 21 is connected to the chemical dosing pump outlet valve 19 in the form of a flange through a pipeline, and a flow meter 33 is installed on the intermediate pipeline. The chemical dosing pump outlet valve 19 is connected to the chemical dosing pump 18 through a pipeline, the chemical dosing pump 18 is connected to the chemical dosing pump inlet valve 17 through a pipeline, and the chemical dosing pump inlet valve 17 is connected to the acid storage tank outlet valve 14 and the alkali storage tank outlet valve 16 through pipelines respectively. The acid storage tank outlet valve 14 extends into the bottom of the acid storage tank 13 through a pipeline, and the alkali storage tank outlet valve 16 extends into the bottom of the alkali storage tank 15 through a pipeline. The on-line pH meter 29 is installed inside the metering and neutralizing tank 21 in the form of a flange and is connected to the pH automatic measurement and chemical dosing controller 31 through a measurement line. Among them, the instrument control signals of the acid storage tank outlet valve 14, the alkali storage tank outlet valve 16, the chemical dosing pump inlet valve 17, the chemical dosing pump outlet valve 19, the chemical dosing pump 18, the flow meter 33 and the liquid level meter 27 are connected to the pH automatic measurement and chemical dosing controller 31 through cables, and the pH automatic measurement and chemical dosing controller 31 is connected to the remote control operation console through a cable line.

[0046] The valves of this system adopt solenoid valves and are automatically controlled by a PLC. The PLC control is programmed using the Siemens S7.0 version to control the solenoid valves in the system, so as to realize the automatic operation and control of the system.

[0047] As shown in the figure, the working process of an automatic metering and neutralization device and method provided by the present invention is as follows:

[0048] First, all the valves in this system are set to the closed state (initial state);

[0049] Step 1: Transport the radioactive concentrated waste liquid to the metering and neutralizing tank

[0050] 1. The concentrated waste liquid generated after the radioactive waste liquid is evaporated by the evaporator of the radioactive waste liquid treatment system is transported to the concentrated waste liquid receiving tank 1 for storage by the concentrated waste pump. After temporary storage and decay, the concentrated waste liquid receiving tank outlet valve 2, the concentrated waste liquid transport pump inlet valve 3, the metering and neutralizing tank inlet valve 20, and the exhaust valve 26 are opened;

[0051] 2. Start the concentrated waste liquid transport pump 4 to transport the radioactive concentrated waste liquid to the metering and neutralizing tank 21. When the measured value of the liquid level meter 27 reaches 70% of the effective volume of the metering and neutralizing tank, stop the concentrated waste liquid transport pump 4 through interlock control and close the metering and neutralizing tank inlet valve 20;

[0052] 3. Close the outlet valve 2 of the concentrated waste liquid receiving tank and the inlet valve 3 of the concentrated waste liquid transfer pump to complete the transfer of radioactive concentrated waste liquid.

[0053] Step 2: Neutralization of radioactive concentrated waste liquid

[0054] Start the PH automatic measurement and dosing controller 31. The online PH meter 29 measures the PH value of the radioactive concentrated waste liquid in the metering neutralization tank 21, and the volume of the radioactive concentrated waste liquid in the metering neutralization tank 21 is obtained through the liquid level gauge 27.

[0055] Start the stirring paddle motor 24 to make the stirring paddle in the working state.

[0056] The PH automatic measurement and dosing controller 31 determines the reagent to be neutralized according to the PH value and volume of the radioactive concentrated waste liquid, calculates the amount of reagent to be added, and performs the neutralization dosing operation through the remote control command.

[0057] If the system determines that the reagent to be added is an acidic solution, the system opens the outlet valve 14 of the acid storage tank, the inlet valve 17 of the dosing pump, and the outlet valve 19 of the dosing pump, then starts the dosing pump 18. When the flowmeter measures the set amount, the system stops the dosing pump 18, and closes the outlet valve 14 of the acid storage tank, the inlet valve 17 of the dosing pump, and the outlet valve 19 of the dosing pump.

[0058] If the system determines that the reagent to be added is an alkaline solution, the system opens the outlet valve 14 of the acid storage tank, the inlet valve 17 of the dosing pump, and the outlet valve 19 of the dosing pump, starts the dosing pump 18. When the flowmeter measures the set amount or the measured value of the liquid level gauge 27 reaches 90% of the effective volume of the metering neutralization tank, the system stops the dosing pump 18, and closes the outlet valve 14 of the acid storage tank, the inlet valve 17 of the dosing pump, and the outlet valve 19 of the dosing pump.

[0059] After the reagent is added to the metering neutralization tank 21, a neutralization reaction occurs in the tank. After a period of time when the neutralization reaction ends, remotely check the measurement value of the online PH meter. If it reaches 6.5 - 7.5, the neutralization reaction ends.

[0060] If the measurement value of the online PH meter is less than 6.5 or greater than 7.5, the system executes according to steps 3 and 4.

[0061] Close the PH automatic measurement and dosing controller 31.

[0062] Step 3: Evaporation and drying of radioactive concentrated waste liquid

[0063] Place the waste barrel in the barrel dryer through the roller track.

[0064] Open the outlet valve 22 of the metering neutralization tank and the inlet valve 5 of the in-bar dryer, and drain the waste liquid in the metering neutralization tank into the in-bar dryer 6. After the liquid level of the in-bar dryer 6 reaches 80%, close the outlet valve 22 of the metering neutralization tank and the inlet valve 5 of the in-bar dryer through interlocking;

[0065] Open the inlet valve 8 of the condenser, start the in-bar dryer for evaporation drying. At this time, the steam passes through the steam-water separation filter 7 and enters the condenser 9 for condensation. After the condensed water generated by condensation reaches a certain liquid level height, open the inlet valve 10 of the condensate discharge pump, the outlet valve 12 of the condensate discharge pump, and start the condensate discharge pump 11 to discharge it to the special sewage discharge collection system in the plant. After the discharge is completed, close the condensate discharge pump 11, and close the inlet valve 10 of the condensate discharge pump and the outlet valve 12 of the condensate discharge pump.

[0066] When the liquid level of the condenser no longer rises within a certain period of time, it indicates that the evaporation of the waste liquid in the in-bar dryer has reached the requirement. At this time, open the outlet valve 22 of the metering neutralization tank and the inlet valve 5 of the in-bar dryer, and drain the waste liquid in the metering neutralization tank into the in-bar dryer 6. After the liquid level of the in-bar dryer reaches a certain height, close the outlet valve 22 of the metering neutralization tank and the inlet valve 5 of the in-bar dryer through interlocking, and cycle until the weight of the in-bar drying device reaches a certain amount or the solid liquid level in the in-bar reaches a certain height, then the heating device stops, and the single-bar evaporation and drying operation is completed;

[0067] Repeat the above steps until all the radioactive concentrated waste liquid in the metering neutralization tank 21 is completely evaporated and dried;

[0068] The waste barrels after evaporation and drying are processed subsequently according to the technological process.

Claims

1. An automatic metering and neutralizing device, comprising an automatic metering unit and an automatic neutralizing unit, characterized in that: The automatic metering unit includes a metering and neutralizing tank inlet valve (20), a metering and neutralizing tank (21), a metering and neutralizing tank outlet valve (22), a stirring paddle (23), a stirring paddle motor (24), a metering and neutralizing tank exhaust filter (25), an exhaust valve (26), a liquid level gauge (27), and a pressure gauge (28); the metering and neutralizing tank inlet valve (20) is connected to the metering and neutralizing tank (21) in a flange form through a pipeline, the bottom of the metering and neutralizing tank (21) is connected to the metering and neutralizing tank outlet valve (22) through a pipeline, and the metering and neutralizing tank outlet valve (22) is connected to the inlet valve (5) of the in-barrel dryer through a pipeline; the top of the metering and neutralizing tank (21) is connected to the metering and neutralizing tank exhaust filter (25) in a flange form through a pipeline, the metering and neutralizing tank exhaust filter (25) is connected to the exhaust valve (26) through a pipeline, the exhaust valve (26) is connected to the plant equipment exhaust system through a pipeline, the top of the metering and neutralizing tank (21) is connected to the liquid level gauge (27) and the pressure gauge (28) in a flange form through a pipeline, a stirring paddle motor (24) is installed at the top of the metering and neutralizing tank (21) and is connected to the stirring paddle (23) through a torsion rod; The automatic neutralizing unit includes an acid storage tank (13), an alkali storage tank (15), a dosing pump (18), an acid storage tank outlet valve (14), an alkali storage tank outlet valve (16), a dosing pump inlet valve (17), a dosing pump outlet valve (19), an in-line pH meter (29), a flange (30), a pH automatic measurement and dosing controller (31), a remote control operation console (32), and a flow meter (33); the top of the metering and neutralizing tank (21) is connected to the dosing pump outlet valve (19) in a flange form through a pipeline, a flow meter (33) is installed on the intermediate pipeline, the dosing pump outlet valve (19) is connected to the dosing pump (18) through a pipeline, the dosing pump (18) is connected to the dosing pump inlet valve (17) through a pipeline, the dosing pump inlet valve (17) is connected to the acid storage tank outlet valve (14) and the alkali storage tank outlet valve (16) respectively through a pipeline, and the acid storage tank outlet valve (14) extends into the bottom of the acid storage tank (13) through a pipeline.

2. An automatic metering and neutralizing device according to claim 1, characterized in that: The alkali storage tank outlet valve (16) extends into the bottom of the alkali storage tank (15) through a pipeline, the in-line pH meter (29) is installed inside the metering and neutralizing tank (21) in a flange form and is connected to the pH automatic measurement and dosing controller (31) through a measurement line, wherein the instrument control signals of the acid storage tank outlet valve (14), the alkali storage tank outlet valve (16), the dosing pump inlet valve (17), the dosing pump outlet valve (19), the dosing pump (18), the flow meter (33), and the liquid level gauge (27) are connected to the pH automatic measurement and dosing controller (31) through cables, and the pH automatic measurement and dosing controller (31) is connected to the remote control operation console through a cable.

3. An automatic metering and neutralizing method, characterized in that: It includes Step 1: transporting the radioactive concentrated waste liquid to a metering and neutralizing tank; Step 2: neutralizing the radioactive concentrated waste liquid; Step 3: evaporating and drying the radioactive concentrated waste liquid; Step 1: transporting the radioactive concentrated waste liquid to a metering and neutralizing tank, including the following steps: (1) After the radioactive waste liquid is evaporated by the evaporator of the radioactive waste liquid treatment system, the generated concentrated waste liquid is transported by a concentrated waste pump to the concentrated waste liquid receiving tank (1) for storage. After temporary storage and decay, the outlet valve (2) of the concentrated waste liquid receiving tank, the inlet valve (3) of the concentrated waste liquid transport pump, the inlet valve (20) of the metering and neutralizing tank, and the exhaust valve (26) are opened; (2) Start the concentrated waste liquid transport pump (4) to transport the radioactive concentrated waste liquid to the metering and neutralizing tank (21). When the liquid level gauge (27) reaches 70% of the effective volume of the neutralizing tank, stop the concentrated waste liquid transport pump (4) and the inlet valve (20) of the metering and neutralizing tank through interlock control; close the outlet valve (2) of the concentrated waste liquid receiving tank and the inlet valve (3) of the concentrated waste liquid transport pump to stop transporting the radioactive concentrated waste liquid; select 30% - 60% dilute sulfuric acid as the neutralizing agent for the radioactive waste liquid; Step 3: evaporating and drying the radioactive concentrated waste liquid, including the following steps: (1) Place the waste barrel on the in-barrel dryer through the roller path; (2) Open the outlet valve (22) of the metering and neutralizing tank and the inlet valve (5) of the in-barrel dryer, and drain the waste liquid in the metering and neutralizing tank into the in-barrel dryer (6). After the liquid level in the in-barrel dryer (6) reaches 80%, close the outlet valve (22) of the metering and neutralizing tank and the inlet valve (5) of the in-barrel dryer through interlock control; (3) Open the inlet valve (8) of the condenser, start the in-barrel dryer for evaporation and drying. At this time, the steam passes through the steam-water separation filter (7) and enters the condenser (9) for condensation. After the condensed water generated by the condensation reaches a certain liquid level height, open the inlet valve (10) of the condensate discharge pump, the outlet valve (12) of the condensate discharge pump, start the condensate discharge pump (11) to discharge it to the special sewage discharge and collection system in the plant. After the discharge is completed, close the condensate discharge pump (11), and close the inlet valve (10) of the condensate discharge pump and the outlet valve (12) of the condensate discharge pump; (4) When the liquid level in the condenser no longer rises within a certain period of time, it indicates that the evaporation of the waste liquid in the in-barrel dryer has reached the requirement. At this time, open the outlet valve (22) of the metering and neutralizing tank and the inlet valve (5) of the in-barrel dryer, and drain the waste liquid in the metering and neutralizing tank into the in-barrel dryer (6). After the liquid level in the in-barrel dryer reaches a certain height, close the outlet valve (22) of the metering and neutralizing tank and the inlet valve (5) of the in-barrel dryer through interlock control, and repeat the cycle until the weight of the in-barrel drying device reaches a certain amount or the solid liquid level in the barrel reaches a certain height, then the heating device stops, and the single-barrel evaporation and drying operation is completed; (5) Repeat the above steps until all the radioactive concentrated waste liquid in the metering and neutralizing tank (21) is completely evaporated and dried; (6) The waste barrels after evaporation and drying are processed subsequently according to the technological process.

4. A method for automatic metering and neutralization as described in claim 3, characterized in that: Step 2: neutralizing the radioactive concentrated waste liquid, including the following steps: (1) Start the PH automatic measurement and dosing controller (31). The on-line PH meter (29) measures the PH value of the radioactive concentrated waste liquid in the metering neutralization tank (21), and obtains the volume of the radioactive concentrated waste liquid in the metering neutralization tank (21) through the liquid level gauge (27). (2) Start the stirring paddle motor (24) to make the stirring paddle in the working state. (3) The PH automatic measurement and dosing controller (31) determines the reagent to be neutralized according to the PH value and volume of the radioactive concentrated waste liquid, calculates the amount of reagent to be added, and performs the neutralization dosing operation through the remote control command.

5. An automatic metering and neutralization method as described in claim 3, characterized in that: Step two: Neutralization of radioactive concentrated waste liquid further includes the following steps: (1) If the system determines that the reagent to be added is an acidic solution, the system opens the outlet valve (14) of the acid storage tank, the inlet valve (17) of the dosing pump, and the outlet valve (19) of the dosing pump, and then starts the dosing pump (18). When the flow meter measures the set amount, the system stops the dosing pump (18), and closes the outlet valve (14) of the acid storage tank, the inlet valve (17) of the dosing pump, and the outlet valve (19) of the dosing pump. (2) If the system determines that the reagent to be added is an alkaline solution, the system opens the outlet valve (14) of the acid storage tank, the inlet valve (17) of the dosing pump, and the outlet valve (19) of the dosing pump, and then starts the dosing pump (18). When the flow meter measures the set amount or the measured value of the liquid level gauge (27) reaches 90% of the effective volume of the metering neutralization tank, the system stops the dosing pump (18), and closes the outlet valve (14) of the acid storage tank, the inlet valve (17) of the dosing pump, and the outlet valve (19) of the dosing pump. (3) After the reagent is added to the metering neutralization tank (21), a neutralization reaction occurs in the tank. After a period of time when the neutralization reaction ends, remotely check the measured value of the on-line PH meter. If it reaches 6.5 - 7.5, the neutralization reaction ends. (4) If the measured value of the on-line PH meter is less than 6.5 or greater than 7.5, the system executes according to steps 3 and 4. (5) Close the PH automatic measurement and dosing controller (31).

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