Radioactive waste resin long-distance, high-fall and non-clogging conveying system and method

Abstract

The invention discloses a radioactive waste resin long-distance, high-fall and non-blocking conveying system and method, and relates to the technical field of radioactive waste resin conveying. The system comprises a radioactive waste resin storage tank, a radioactive waste resin backflow pipeline and a radioactive waste resin conveying pipeline provided with a double-screw pump. The radioactive waste resin conveying pipeline is provided with a pre-pumping flushing liquid flushing inlet, a post-pumping flushing liquid flushing inlet, a post-pumping backflow outlet and a post-pumping waste resin conveying outlet, and the post-pumping backflow outlet is connected with a backflow inlet of the radioactive waste resin storage tank through a radioactive waste resin backflow pipeline. And when the waste resin is conveyed, flushing fluid is introduced into the pre-pumping flushing fluid flushing inlet and / or the post-pumping flushing fluid flushing inlet according to the conveying pressure and flow, so that the internal pressure of the double-screw pump during operation is adjusted. The problem of blockage in the long-distance and high-fall conveying process of radioactive waste resin is solved, the conveying efficiency is improved, and facility corrosion and transfer risks are reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of radioactive waste resin transportation, and in particular to a system and method for long-distance, high-drop, non-blocking transportation of radioactive waste resin. Background Art

[0002] As a special waste stream in the nuclear industry, radioactive waste resin is one of the important factors affecting the healthy and sustainable development of the nuclear industry. Its storage method is to temporarily store the waste resin and its radioactive soaking liquid in a storage container. A large amount of radioactive waste resin and its radioactive soaking liquid generated by some old nuclear facilities during production and operation are temporarily stored in large underground tanks.

[0003] Waste resins contain high concentrations of radionuclides, long half-lives, and high toxicity. They also contain elements such as sulfur and nitrogen, which can be highly corrosive to storage facilities if stored for long periods of time. If waste resins are stored for too long, they will become powdery, making it more difficult to transport and handle them.

[0004] The density of waste resin is greater than that of the soaking liquid, so it is deposited at the bottom of the soaking liquid. In order to transport the waste resin, it must be stirred and suspended first. Since the waste resin deposits quickly, it is very easy to deposit and block pipes or valves during long-distance and high-drop transportation, thereby affecting or even interrupting the smooth progress of production. Regardless of the waste resin treatment technology adopted, the waste resin must be transported. In view of the current status of engineering applications, being able to transport waste resin over long distances and high drops without clogging is a common problem in waste resin treatment technology.

[0005] Domestic nuclear power plants also produce a large amount of radioactive waste resin every year. In order to avoid the blockage of pipeline valves caused by long-distance transportation of waste resin, nuclear power plants generally use shielding containers to directly connect with the temporary storage tanks for waste resin. After the shielding container reaches a certain volume, it is transferred to the waste resin processing production line by a transfer vehicle. This avoids the risk of blockage caused by long-distance transportation of waste resin, but the volume of the shielding container is small, so it takes a long time and multiple transfers to meet the needs of the waste resin production line. In addition, there is a risk of valves and some hoses leaking during the transportation of the shielding container loaded by the transfer vehicle. Summary of the invention

[0006] The present invention provides a long-distance, high-drop, non-blocking conveying system and method for radioactive waste resin, which can solve the above-mentioned problems.

[0007] In order to solve the above problems, the technical solution adopted by the present invention is as follows:

[0008] In the first aspect, the present invention provides a long-distance, high-drop, non-clogging conveying system for radioactive waste resin, comprising a radioactive waste resin storage tank, a radioactive waste resin reflux pipeline and a radioactive waste resin conveying pipeline equipped with a twin-screw pump; the radioactive waste resin conveying pipeline is provided with a pre-pump flushing liquid flushing inlet, a post-pump flushing liquid flushing inlet, a post-pump reflux outlet and a post-pump waste resin conveying outlet, and the post-pump reflux outlet is connected to the reflux inlet of the radioactive waste resin storage tank through the radioactive waste resin reflux pipeline.

[0009] Furthermore, the radioactive waste resin conveying pipeline is also provided with a twin-screw pump pressure gauge and a twin-screw pump flow meter, and the twin-screw pump, the twin-screw pump pressure gauge and the twin-screw pump flow meter are arranged in sequence according to the waste resin conveying direction, and the rear reflux outlet of the pump is located between the twin-screw pump and the twin-screw pump pressure gauge.

[0010] Furthermore, the radioactive waste resin conveying pipeline is also provided with a first manual inlet valve of the twin-screw pump, a first electric inlet valve of the twin-screw pump, a second manual outlet valve of the twin-screw pump and a second electric outlet valve of the twin-screw pump; the first manual inlet valve of the twin-screw pump, the first electric inlet valve of the twin-screw pump, the flushing inlet of the flushing liquid before the pump, the twin-screw pump, the flushing inlet of the flushing liquid after the pump, the second manual outlet valve of the twin-screw pump, the reflux outlet after the pump, the pressure gauge of the twin-screw pump, the flow meter of the twin-screw pump, the second electric outlet valve of the twin-screw pump and the waste resin conveying outlet after the pump are arranged in sequence according to the waste resin conveying direction.

[0011] Furthermore, a first flushing liquid input electric control valve is provided at the flushing liquid flushing inlet before the pump, and a second flushing liquid input electric control valve is provided at the flushing liquid flushing inlet after the pump. The inlets of the first flushing liquid input electric control valve and the second flushing liquid input electric control valve are both connected to a flushing liquid supply system, and a flushing liquid supply flow meter is provided on the flushing liquid output side of the flushing liquid supply system.

[0012] Furthermore, the radioactive waste resin reflux pipeline is provided with a twin-screw pump electric reflux valve.

[0013] In a second aspect, the present invention provides a method for long-distance, high-drop, non-blocking transportation of radioactive waste resin, which uses the system described in the first aspect and includes the following steps:

[0014] (1) After the radioactive waste resin in the radioactive waste resin storage tank is stirred and suspended and the volume percentage concentration of the waste resin is adjusted to 30-50%, the first manual inlet valve, the first electric inlet valve, the second manual outlet valve and the second electric outlet valve of the twin screw pump are opened, the first flushing liquid input electric control valve and the second flushing liquid input electric control valve are kept closed, and the twin screw pump is started to start conveying the radioactive waste resin;

[0015] (2) opening the electric reflux valve of the twin-screw pump, and adjusting the internal pressure of the twin-screw pump during operation based on controlling the waste resin delivery concentration according to the pressure value displayed on the twin-screw pump pressure gauge and the flow value displayed on the flushing liquid supply flow meter, that is, according to the delivery pressure and flow, flushing liquid is introduced into the front flushing inlet of the pump and / or the rear flushing inlet of the pump to flush the front and / or rear side of the twin-screw pump, thereby adjusting the internal pressure of the twin-screw pump during operation, and the adjustment method specifically includes:

[0016] When the pressure value rises to 0.37-0.50Mpa, the first flushing liquid input electric control valve is opened to flush the inlet side of the twin-screw pump with flushing liquid, and the opening degree of the first flushing liquid input electric control valve is such that the flow value displayed on the flushing liquid supply flow meter is 2-4m 3 / h, when the pressure value drops to less than 0.36Mpa and lasts for 2 minutes, the first flushing liquid input electric control valve is closed;

[0017] When the pressure value is greater than 0.50 MPa and continues to rise, the first flushing liquid input electric control valve and the second flushing liquid input electric control valve need to be opened simultaneously to flush the inlet and outlet sides of the twin-screw pump with flushing liquid, and the opening degree of the first flushing liquid input electric control valve and the second flushing liquid input electric control valve is such that the flow value displayed by the flushing liquid supply flow meter (14) is 4 to 5 m / s. 3 / h, when the pressure value drops to less than 0.36Mpa and lasts for 2 minutes, the first flushing liquid input electric control valve and the second flushing liquid input electric control valve are closed.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] 1) By using a twin-screw pump as the conveying equipment, combined with the adjustment of flushing liquid and dynamic control of process operating parameters, the technical problem of radioactive waste resin being easily deposited and blocked in pipes or valves during long-distance and high-drop transportation was effectively solved, ensuring the continuity and stability of the transportation process.

[0020] 2) By precisely controlling the waste resin delivery concentration and internal pressure, delivery interruptions due to blockages are reduced, the delivery efficiency of the waste resin is significantly improved, and the time and resource waste caused by frequent clearing of blockages is reduced.

[0021] 3) By reducing the temporary storage time of waste resin in the storage facility, the corrosive effect of the waste resin on the storage facility is reduced, the service life of the facility is extended, and the maintenance cost is reduced.

[0022] 4) By stirring, suspending and precisely controlling the conveying process, the pulverization of waste resin is effectively addressed, the impact of pulverized waste resin on the conveying system is reduced, and the reliability of the conveying system is improved.

[0023] 5) Compared with the traditional shielded container transfer method, it avoids the risk of valve and hose leakage during the transfer process, and reduces environmental pollution and personnel health risks.

[0024] 6) It provides a continuous, safe and stable production and operation basis for the waste resin treatment production line, ensures the high efficiency and safety of nuclear industry waste resin treatment, and is of great significance to the healthy and sustainable development of the nuclear industry.

[0025] 7) By reducing the risk of waste resin leakage and improving the transportation efficiency, it helps to reduce environmental pollution and protect the health of operators, and meets the requirements of nuclear safety and environmental protection.

[0026] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the embodiments of the present invention are specifically cited below and described in detail with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0028] Figure 1 Schematic diagram of a long-distance, high-drop, non-clogging conveying system for radioactive waste resin according to an embodiment;

[0029] In the figure: 1. Radioactive waste resin storage tank; 2. Twin-screw pump; 3. First manual inlet valve of twin-screw pump; 4. First electric inlet valve of twin-screw pump; 5. Second manual outlet valve of twin-screw pump; 6. Second electric outlet valve of twin-screw pump; 7. Pressure gauge of twin-screw pump; 8. Flow meter of twin-screw pump; 9. Electric reflux valve of twin-screw pump; 10. Radioactive waste resin delivery pipeline; 11. Reflux pipeline of radioactive waste resin; 12. First flushing liquid input electric control valve; 13. Second flushing liquid input electric control valve; 14. Flushing liquid supply flow meter. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments.

[0031] Please refer to Figure 1 This embodiment provides a long-distance (greater than 100 meters), high-drop (greater than 10 meters) non-clogging transportation system for radioactive waste resin, including a radioactive waste resin storage tank 1, a radioactive waste resin reflux pipeline 11 and a radioactive waste resin transportation pipeline 10.

[0032] The radioactive waste resin reflux pipeline 11 is provided with a twin-screw pump electric reflux valve 9 .

[0033] The radioactive waste resin conveying pipeline 10 is provided with a pre-pump flushing liquid flushing inlet, a post-pump flushing liquid flushing inlet, a post-pump reflux outlet and a post-pump waste resin conveying outlet, and the post-pump reflux outlet is connected to the reflux inlet of the radioactive waste resin storage tank 1 through the radioactive waste resin reflux pipeline 11.

[0034] The radioactive waste resin conveying pipeline 10 is also provided with a twin-screw pump 2, a twin-screw pump pressure gauge 7, a twin-screw pump flow meter 8, a first manual inlet valve 3 of the twin-screw pump, a first electric inlet valve 4 of the twin-screw pump, a second manual outlet valve 5 of the twin-screw pump and a second electric outlet valve 6 of the twin-screw pump. The first manual inlet valve of the screw pump, the first electric inlet valve of the twin-screw pump 4, a flushing inlet of flushing liquid before the pump, the twin-screw pump 2, a flushing inlet of flushing liquid after the pump, the second manual outlet valve 5 of the twin-screw pump, a reflux outlet after the pump, a twin-screw pump pressure gauge 7, a twin-screw pump flow meter 8, the second electric outlet valve 6 of the twin-screw pump and a waste resin conveying outlet after the pump are arranged in sequence according to the waste resin conveying direction.

[0035] A first flushing liquid input electric control valve 12 is provided at the flushing inlet of the flushing liquid before the pump, and a second flushing liquid input electric control valve 13 is provided at the flushing inlet of the flushing liquid after the pump. The inlets of the first flushing liquid input electric control valve 12 and the second flushing liquid input electric control valve 13 are both connected to the flushing liquid supply system, and a flushing liquid supply flow meter 14 is provided on the flushing liquid output side of the flushing liquid supply system.

[0036] The method for long-distance, high-drop, non-blocking transportation of radioactive waste resin based on the transportation system of this embodiment comprises the following steps:

[0037] (1) After the radioactive waste resin in the radioactive waste resin storage tank 1 is stirred and suspended, and the volume percentage concentration of the waste resin is adjusted to 30-50%, the first manual inlet valve 3 of the twin-screw pump, the first electric inlet valve 4 of the twin-screw pump, the second manual outlet valve 5 of the twin-screw pump, and the second electric outlet valve 6 of the twin-screw pump are opened, the first flushing liquid input electric control valve 12 and the second flushing liquid input electric control valve 13 remain closed, and the twin-screw pump 2 is started to start conveying the radioactive waste resin;

[0038] (2) Open the electric reflux valve 9 of the twin-screw pump, and adjust the internal pressure of the twin-screw pump 2 during operation based on the control of the waste resin delivery concentration according to the pressure value displayed on the twin-screw pump pressure gauge 7 and the flow value displayed on the flushing liquid supply flow meter 14. That is, according to the delivery pressure and flow rate, introduce flushing liquid (the flushing liquid can be the supernatant from another waste resin storage tank outside the system, or the production water in the factory) into the flushing inlet of the front flushing liquid of the pump and / or the flushing inlet of the rear flushing liquid of the pump to flush the front and / or rear side of the twin-screw pump 2, so as to adjust the internal pressure of the twin-screw pump 2 during operation. The adjustment method specifically includes:

[0039] When the pressure value is between 0.33 and 0.36 MPa, the system is in normal operation and no adjustment is required. At this time, the flow rate value is not less than 2 m 3 / h, to meet the production demand for radioactive waste resin treatment;

[0040] When the pressure value rises to 0.37-0.50Mpa, the first flushing liquid input electric control valve 12 is opened to flush the inlet side of the twin-screw pump 2 with the flushing liquid, and the opening degree of the first flushing liquid input electric control valve 12 is such that the flow value displayed by the clear liquid supply flow meter 14 is 2-4m 3 / h, when the pressure value drops to less than 0.36Mpa and lasts for 2 minutes, the first flushing liquid input electric control valve 12 is closed, and the system resumes normal operation, that is, the flow value displayed by the twin-screw pump flow meter 8 is not less than 2m 3 / h;

[0041] When the pressure value is greater than 0.50Mpa and continues to rise, the first flushing liquid input electric control valve 12 and the second flushing liquid input electric control valve 13 need to be opened at the same time. The opening degree of the first flushing liquid input electric control valve 12 and the second flushing liquid input electric control valve 13 is such that the flow value displayed by the clear liquid supply flow meter 14 is 4-5m 3 / h, flush the inlet and outlet sides of the twin-screw pump 2 with flushing liquid. When the pressure value drops to less than 0.36Mpa and lasts for 2 minutes, close the first flushing liquid input electric control valve 12 and the second flushing liquid input electric control valve 13. At this time, the system resumes normal operation, that is, the flow value displayed by the twin-screw pump flow meter 8 is not less than 2m 3 / h.

[0042] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A long-distance, high-drop, non-blocking conveying system for radioactive waste resin, characterized in that: The invention comprises a radioactive waste resin storage tank (1), a radioactive waste resin reflux pipeline (11) and a radioactive waste resin conveying pipeline (10) provided with a twin-screw pump (2); the radioactive waste resin conveying pipeline (10) is provided with a pre-pump flushing liquid flushing inlet, a post-pump flushing liquid flushing inlet, a post-pump reflux outlet and a post-pump waste resin conveying outlet; the post-pump reflux outlet is connected to the reflux inlet of the radioactive waste resin storage tank (1) through the radioactive waste resin reflux pipeline (11).

2. The system according to claim 1, characterized in that The radioactive waste resin conveying pipeline (10) is also provided with a twin-screw pump pressure gauge (7) and a twin-screw pump flow meter (8); the twin-screw pump (2), the twin-screw pump pressure gauge (7) and the twin-screw pump flow meter (8) are arranged in sequence according to the waste resin conveying direction; and the rear reflux outlet of the pump is located between the twin-screw pump (2) and the twin-screw pump pressure gauge (7).

3. The system according to claim 2, characterized in that The radioactive waste resin conveying pipeline (10) is also provided with a first manual inlet valve (3) of the twin screw pump, a first electric inlet valve (4) of the twin screw pump, a second manual outlet valve (5) of the twin screw pump and a second electric outlet valve (6) of the twin screw pump; the first manual inlet valve (3) of the twin screw pump, the first electric inlet valve (4) of the twin screw pump, a flushing inlet of a flushing liquid before the pump, the twin screw pump (2), a flushing inlet of a flushing liquid after the pump, the second manual outlet valve (5) of the twin screw pump, a reflux outlet after the pump, a pressure gauge (7) of the twin screw pump, a flow meter (8) of the twin screw pump, the second electric outlet valve (6) of the twin screw pump and a waste resin conveying outlet after the pump are arranged in sequence according to the conveying direction of the waste resin.

4. The system according to claim 3, characterized in that A first flushing liquid input electric control valve (12) is provided at the flushing liquid flushing inlet before the pump, and a second flushing liquid input electric control valve (13) is provided at the flushing liquid flushing inlet after the pump. The inlets of the first flushing liquid input electric control valve (12) and the second flushing liquid input electric control valve (13) are both connected to a flushing liquid supply system, and a flushing liquid supply flow meter (14) is provided on the flushing liquid output side of the flushing liquid supply system.

5. The system according to claim 4, characterized in that The radioactive waste resin reflux pipeline (11) is provided with a twin-screw pump electric reflux valve (9).

6. A method for transporting radioactive waste resin over long distances and at high drop heights without clogging, characterized in that: The system of claim 5 is used, comprising the following steps: (1) After the radioactive waste resin in the radioactive waste resin storage tank (1) is stirred and suspended, and the volume percentage concentration of the waste resin is adjusted to 30-50%, the first manual inlet valve (3) of the twin-screw pump, the first electric inlet valve (4) of the twin-screw pump, the second manual outlet valve (5) of the twin-screw pump, and the second electric outlet valve (6) of the twin-screw pump are opened, the first flushing liquid input electric control valve (12) and the second flushing liquid input electric control valve (13) are kept closed, and the twin-screw pump (2) is started to start conveying the radioactive waste resin; (2) opening the electric reflux valve (9) of the twin-screw pump, adjusting the internal pressure of the twin-screw pump (2) during operation based on controlling the waste resin delivery concentration according to the pressure value displayed by the twin-screw pump pressure gauge (7) and the flow value displayed by the flushing liquid supply flow meter (14), and adjusting the internal pressure of the twin-screw pump (2) during operation, the adjustment method comprising: When the pressure value rises to 0.37-0.50 MPa, the first flushing liquid input electric control valve (12) is opened to flush the inlet side of the twin-screw pump (2) with the flushing liquid, and the opening degree of the first flushing liquid input electric control valve (12) is such that the flow value displayed by the flushing liquid supply flow meter (14) is 2-4 m / s. 3 / h, when the pressure value drops to less than 0.36Mpa and lasts for 2 minutes, the first flushing liquid input electric control valve (12) is closed; When the pressure value is greater than 0.50 MPa and continues to rise, the first flushing liquid input electric control valve (12) and the second flushing liquid input electric control valve (13) need to be opened simultaneously, and the inlet side and the outlet side of the twin-screw pump (2) are flushed with flushing liquid, and the opening degree of the first flushing liquid input electric control valve (12) and the second flushing liquid input electric control valve (13) is such that the flow value displayed on the flushing liquid supply flow meter (14) is 4 to 5 m / s. 3 / h, when the pressure value drops to less than 0.36Mpa and lasts for 2 minutes, the first flushing liquid input electric control valve (12) and the second flushing liquid input electric control valve (13) are closed.

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