Nuclear waste treatment system and method

Abstract

The invention discloses a nuclear waste treatment system and method, and relates to the technical field of nuclear waste treatment. The system comprises a plasma pyrolysis unit and a dust removal adsorption unit. The plasma pyrolysis unit comprises a first combustion furnace, a communicating pipe, a second combustion furnace, a gas outlet pipe and a plurality of plasma output assemblies. The communicating pipe is connected with the first combustion furnace and the second combustion furnace. The multiple plasma output assemblies are connected with the first combustion furnace and the second combustion furnace correspondingly and can output high-temperature active groups to the first combustion furnace and the second combustion furnace correspondingly. And the nuclear waste can be combusted under the action of the high-temperature active groups to generate mixed flue gas. The dust removal adsorption unit comprises a filtering washer and an adsorber which are connected with each other. An adsorption material configured by the adsorber comprises catechin. Therefore, when the nuclear waste is treated by the plasma pyrolysis gasification technology, the mixed flue gas is treated by the adsorbent rich in catechin, and the adsorption of nitrogen oxides and radioactive substances such as iodine and cesium can be realized at the same time.

Description

TECHNICAL FIELD

[0001] The present specification relates to the technical field of nuclear waste treatment, and particularly relates to a nuclear waste treatment system and method. BACKGROUND

[0002] With the rapid development of nuclear power industry, the amount of radioactive waste is increasing. Generally, nuclear waste includes waste gas, waste oil, waste paper, waste cloth, waste plastic, and some equipment, tools, filter elements generated in nuclear power plants and nuclear fuel reprocessing plants.

[0003] In the prior art, nuclear waste is generally treated by cement solidification or plasma pyrolysis gasification technology. Compared with the traditional cement solidification treatment technology, the plasma pyrolysis gasification technology has the advantages of wide application range, fast reaction speed, small secondary pollution, small tail gas amount and compact equipment, but in the process of treating nuclear waste, a large amount of nitrogen oxides is often generated, which needs to be treated additionally. SUMMARY

[0004] The present specification provides a nuclear waste treatment system and method to at least partially solve the above problems existing in the prior art.

[0005] The present specification adopts the following technical solutions:

[0006] The present specification provides a nuclear waste treatment system, comprising a plasma pyrolysis unit and a dust adsorption unit;

[0007] The plasma pyrolysis unit comprises a first combustion furnace, a connecting pipe, a second combustion furnace, an exhaust pipe and a plurality of plasma output assemblies; the connecting pipe is connected with the first combustion furnace and the second combustion furnace respectively; the first combustion furnace is provided with a feed port filled with nuclear waste; the plurality of plasma output assemblies are connected with the first combustion furnace and the second combustion furnace respectively, and can output high-temperature active groups to the first combustion furnace and the second combustion furnace respectively; the nuclear waste can be preliminarily combusted and generate pyrolysis mixed gas under the action of the high-temperature active groups; the pyrolysis mixed gas transmitted to the second combustion furnace through the connecting pipe can be fully combusted and generate mixed flue gas under the action of the active groups; the mixed flue gas at least includes nitrogen oxides, iodine and cesium;

[0008] The dust adsorption unit comprises a filter scrubber and an adsorber connected with each other; the filter scrubber is connected with the second combustion furnace and can perform dust removal and acid removal washing on the mixed flue gas; the adsorber is configured with an adsorption material for adsorbing nitrogen oxides, iodine and cesium in the mixed flue gas through the adsorption material; the adsorption material comprises catechin.

[0009] Preferably, the nuclear waste treatment system further comprises a denitration cooling unit;

[0010] The denitration cooling unit is arranged between the plasma pyrolysis unit and the dust adsorption unit.

[0011] The cooling unit comprises a non-contact denitration assembly and a rapid cooling assembly connected with each other.

[0012] The non-contact denitration assembly is connected with the second combustion furnace, and can filter nitrogen oxides in the mixed flue gas by a chemical solution.

[0013] The rapid cooling assembly can reduce the temperature of the mixed flue gas, and the rapid cooling assembly is connected with the filter scrubber, and can deliver the mixed flue gas after temperature reduction to the filter scrubber.

[0014] Preferably, the adsorber comprises a first adsorption subunit and a second adsorption subunit.

[0015] The first adsorption subunit and the second adsorption subunit are both connected with the filter scrubber through a connecting pipeline; the first adsorption subunit and / or the second adsorption subunit and / or the connecting pipeline are provided with a switch; the switch can be opened or closed, and the change of the switch state can cause the mixed flue gas to switch between flowing to the first adsorption subunit and flowing to the second adsorption subunit.

[0016] Preferably, the concentration of nitrogen oxides in the mixed flue gas flowing to the adsorber is between 500-2500Nm 3 / h, the concentration of iodine is between 1000-3000mg / Kg, and the concentration of cesium is between 2000-4000mg / Kg.

[0017] The adsorption efficiency of the adsorption material for the nitrogen oxides, the iodine and the cesium is greater than or equal to 90%.

[0018] Preferably, the adsorption material further comprises nano-porous attapulgite and / or malondialdehyde and / or triethanolamine.

[0019] Preferably, the system further comprises a solidification unit.

[0020] The first combustion furnace and / or the second combustion furnace are further provided with an ash outlet; the first combustion furnace and the second combustion furnace are further used for discharging ash from the ash outlet.

[0021] The solidification unit is used for cement solidification and / or high-temperature molten glass solidification of the ash.

[0022] Preferably, the dust adsorption unit further comprises a gas-liquid separator.

[0023] The gas-liquid separator is arranged between the filter scrubber and the adsorber, and is connected with the filter scrubber and the adsorber respectively, and is used to obtain the mixed flue gas transmitted from the filter scrubber, separate the water vapor in the mixed flue gas, and transmit the mixed flue gas with separated water vapor to the adsorber.

[0024] The concentration of water vapor in the mixed flue gas transmitted by the gas-liquid separator to the adsorber is less than or equal to 100 mg / m 3 .

[0025] Preferably, the first combustion furnace and / or the second combustion furnace is / are provided with an air inlet for adding combustion-supporting agents.

[0026] In another aspect, the present specification also provides a nuclear waste treatment method using the nuclear waste treatment system provided in the above aspect, comprising:

[0027] In the first combustion furnace, the nuclear waste is preliminarily combusted by the high-temperature active groups exhaled by the plasma output assembly to generate pyrolysis mixed gas;

[0028] In the second combustion furnace, the pyrolysis mixed gas is combusted by the high-temperature active groups exhaled by the plasma output assembly to generate mixed flue gas; the mixed flue gas at least includes nitrogen oxides, iodine and cesium;

[0029] The macromolecular solid particles in the mixed flue gas are filtered by the filter scrubber, and the mixed flue gas is deacidified and washed;

[0030] In the adsorber, the nitrogen oxides, iodine and cesium in the mixed flue gas are adsorbed by the adsorption material; the adsorption material includes catechin.

[0031] Preferably, before the macromolecular solid particles in the mixed flue gas are filtered by the filter scrubber, the method further comprises:

[0032] The nitrogen oxides in the mixed flue gas are filtered by the chemical solution in the non-contact denitration assembly;

[0033] The mixed flue gas is cooled by the rapid cooling assembly.

[0034] The above at least one technical scheme adopted by the present specification can achieve the following beneficial effects:

[0035] The nuclear waste treatment system comprises a plasma pyrolysis unit and a dust removal and adsorption unit. The plasma pyrolysis unit comprises a first combustion furnace, a connecting pipe, a second combustion furnace, an exhaust pipe and a plurality of plasma output assemblies. The connecting pipe is connected with the first combustion furnace and the second combustion furnace respectively, and the first combustion furnace is provided with a feed inlet filled with nuclear waste. The plurality of plasma output assemblies are connected with the first combustion furnace and the second combustion furnace respectively, and can output high-temperature active groups to the first combustion furnace and the second combustion furnace respectively. The nuclear waste can be preliminarily combusted under the action of the high-temperature active groups and generate pyrolysis mixed gas, and the pyrolysis mixed gas transmitted into the second combustion furnace through the connecting pipe can be fully combusted under the action of the active groups and generate mixed flue gas. The dust removal and adsorption unit comprises a filter scrubber and an adsorber connected with each other, the filter scrubber is connected with the second combustion furnace and can perform dust removal and deacidification washing on the mixed flue gas. The adsorber is provided with an adsorption material for adsorbing nitrogen oxides, iodine and cesium in the mixed flue gas through the adsorption material. The adsorption material comprises catechin.

[0036] According to the above, based on the plasma output assembly and other devices, the nuclear waste is treated by using the plasma pyrolysis gasification technology which has higher efficiency and lower cost, and for more disadvantages of nitrogen oxides generated by the plasma pyrolysis gasification technology, the adsorbent rich in catechin is used for treatment, which can realize the adsorption of nitrogen oxides, iodine and cesium and other radioactive substances at the same time without additional operation. BRIEF DESCRIPTION OF DRAWINGS

[0037] The drawings described herein are used to provide further understanding of the present specification, constitute a part of the present specification, the illustrative embodiments of the present specification and the description thereof are used to explain the present specification, and do not constitute improper limitation on the present specification. In the drawings:

[0038] Figure 1 The structure schematic diagram of the nuclear waste treatment system provided by an embodiment of the present application is shown;

[0039] Figure 2 The partial structure schematic diagram of the nuclear waste treatment system provided by an embodiment of the present application is shown;

[0040] Figure 3 The structure schematic diagram of the gas inlet provided by an embodiment of the present specification is shown;

[0041] Figure 4 The structure schematic diagram of the nuclear waste treatment system provided by an embodiment of the present specification is shown;

[0042] Figure 5 The flow schematic diagram of the nuclear waste treatment method provided by an embodiment of the present specification is shown.

[0043] Explanation of reference signs:

[0044] plasma pyrolysis unit 1; dust removal and adsorption unit 2; first combustion furnace 11; connecting pipe 12; second combustion furnace 13; gas outlet pipe 14; gas inlet 111; feed inlet 112; plasma output assembly 113; gasification pyrolysis layer 114; ash outlet 115; non-contact denitration assembly 31; heat exchanger 32; quench tower 33; first filter 34; second filter 35; primary scrubbing tower 36; secondary scrubbing tower 37; flue gas cooler 38; gas-liquid separator 39; first absorption accessory 41; second absorption accessory 42; electric heater 43; induced draft fan 44. DETAILED DESCRIPTION

[0045] For the purpose, technical solutions and advantages of the present application, the technical solutions of the present application will be described in detail below with reference to the specific embodiments of the present application and corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of the present application.

[0046] In the description of the present application, it should be noted that the term "or" is generally used in the sense of including "and / or" unless the context clearly indicates otherwise.

[0047] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connecting" should be understood in a broad sense. In addition, in the description of the present application, the terms "first", "second" and the like are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0048] Obviously, the described embodiments are only a part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of the present application.

[0049] The technical solutions provided by each embodiment of the present application will be described in detail below with reference to the drawings.

[0050] Figure 1 The structure schematic diagram of the nuclear waste treatment system provided by an embodiment of the present application is shown in Figure 1 The nuclear waste treatment system includes a plasma pyrolysis unit and a dust removal and adsorption unit 2.

[0051] Preferably, the nuclear waste includes cotton and / or clothes and / or polyethylene and / or resin, etc. Among them, the material of the clothes includes hemp, silk, wool, leather, chemical fiber, polyester, etc. in addition to cotton, which is not limited in the present application.

[0052] Preferably, the plasma pyrolysis unit comprises a first combustion furnace 11, a connecting pipe 12, a second combustion furnace 13, an exhaust pipe 14 and a plurality of plasma output assemblies 113.

[0053] Figure 2 A schematic diagram of a part of a nuclear waste treatment system according to an embodiment of the present application is shown in Fig. 1. As shown, a first combustion furnace 11, a connecting pipe 12, a second combustion furnace 13 and an exhaust pipe 14 are connected in sequence, and a plurality of plasma output assemblies 113 are connected to the first combustion furnace 11 and the second combustion furnace 13, respectively. Figure 2

[0054] Preferably, the first combustion furnace 11 is configured to combust the nuclear waste for the first time.

[0055] Preferably, the first combustion furnace 11 is provided with a feeding port 112, an air inlet 111, an air outlet, a combustion hole and an ash outlet 115. The feeding port 112 is configured to fill the nuclear waste, and the air outlet is connected to the connecting pipe 12 and configured to output pyrolysis mixed gas to the second combustion furnace 13. The combustion hole is configured to accommodate at least part of the plasma output assembly 113, so that the plasma output assembly 113 can output high-temperature active groups into the first combustion furnace 11.

[0056] Preferably, the plasma output assembly 113 comprises a carrier wind generator, a plasma torch and a cooler. Of course, those skilled in the art can understand that the related technology of the plasma output assembly 113 has been relatively mature, and the present description does not limit the structure of the plasma output assembly 113.

[0057] Preferably, the air inlet 111 is configured to input combustion-supporting agent.

[0058] Preferably, the second combustion furnace 13 is provided with a combustion hole, an air inlet 111, a connecting port and a discharging port. Further preferably, there is one or more combustion holes, and any one of the combustion holes is configured to accommodate at least part of the plasma output assembly 113, so that the plasma output assembly 113 can output high-temperature active groups into the second combustion furnace 13. The air inlet 111 is configured to input combustion-supporting agent. The connecting port is configured to be connected to the connecting pipe 12. The discharging port is configured to be connected to the dust adsorption unit 2. The air inlet 111 is configured to input combustion-supporting agent.

[0059] Preferably, the combustion-supporting agent can be sent into the air inlet 111 of the first combustion furnace 11 and / or the second combustion furnace 13 by a blower or the like, which is not limited in the present description.

[0060] Preferably, the connecting pipe 12 is connected to the first combustion furnace 11 and the second combustion furnace 13, respectively.​

[0061] Preferably, the plurality of plasma output assemblies 113 are respectively connected to the first combustion furnace 11 and the second combustion furnace 13, and are capable of outputting high-temperature active groups to the first combustion furnace 11 and the second combustion furnace 13 respectively.

[0062] Preferably, the nuclear waste can be preliminarily combusted and generate pyrolysis mixed gas under the action of the high-temperature active groups.

[0063] Preferably, the pyrolysis mixed gas can be transmitted into the second combustion furnace 13 through the gas outlet, the communication pipe 12 and the communication port.

[0064] Preferably, the pyrolysis mixed gas in the second combustion furnace 13 can be fully combusted and generate mixed flue gas under the action of the high-temperature active groups.

[0065] As understood by those skilled in the art, the plasma has the characteristics of high temperature and high enthalpy, and in the process of combusting the nuclear waste by the high-temperature active groups output by the plasma output assemblies 113, the plasma will also generate a large amount of nitrogen oxides based on the nitrogen in the air and the nitrogen-containing organic matter in the nuclear waste. Therefore, the pyrolysis mixed gas generated after the nuclear waste is combusted not only includes gas containing radioactive elements such as cesium (Cs-137) and iodine (I-131), but also contains a large amount of nitrogen oxides.

[0066] Preferably, the content of nitrogen oxides in the mixed flue gas is 2000mg / m 3 -4000mg / m 3 .

[0067] Preferably, the dust removal and adsorption unit 2 includes a filter scrubber and an adsorber connected to each other.

[0068] Preferably, the filter scrubber is connected to the second combustion furnace 13 and is capable of dust removal and deacidification washing of the mixed flue gas.

[0069] Preferably, the adsorber is provided with an adsorption material for adsorbing nitrogen oxides, iodine and cesium in the mixed flue gas by the adsorption material.

[0070] Preferably, the adsorption material includes catechin.

[0071] According to the above embodiment, the nuclear waste treatment system comprises a plasma pyrolysis unit and a dust removal and adsorption unit 2. The plasma pyrolysis unit comprises a first combustion furnace 11, a connecting pipe 12, a second combustion furnace 13, an exhaust pipe 14, and a plurality of plasma output assemblies 113. The connecting pipe 12 is connected with the first combustion furnace 11 and the second combustion furnace 13 respectively, and the first combustion furnace 11 is provided with a feed port 112 filled with nuclear waste. The plurality of plasma output assemblies 113 are connected with the first combustion furnace 11 and the second combustion furnace 13 respectively, and can output high-temperature active groups to the first combustion furnace 11 and the second combustion furnace 13 respectively. The nuclear waste can be preliminarily combusted under the action of the high-temperature active groups to generate pyrolysis mixed gas, and the pyrolysis mixed gas transmitted into the second combustion furnace 13 through the connecting pipe 12 can be fully combusted under the action of the active groups to generate mixed flue gas. The dust removal and adsorption unit 2 comprises a filter scrubber and an adsorber connected with each other, the filter scrubber is connected with the second combustion furnace 13 and can perform dust removal and deacidification washing on the mixed flue gas. The adsorber is configured with adsorption material for adsorbing nitrogen oxides, iodine and cesium in the mixed flue gas through the adsorption material. The adsorption material comprises catechin.

[0072] According to the above, based on the plasma output assembly 113 and other devices, the nuclear waste is treated by using the plasma pyrolysis gasification technology which has higher efficiency and lower cost, and for more disadvantages of nitrogen oxides generated by the plasma pyrolysis gasification technology, the adsorbent rich in catechin is used for treatment, which can realize the adsorption of nitrogen oxides and radioactive substances such as iodine and cesium at the same time without additional operation.

[0073] Preferably, the nuclear waste treatment system further comprises a denitration cooling unit.

[0074] Preferably, the denitration cooling unit is arranged between the plasma pyrolysis unit and the dust removal and adsorption unit 2.

[0075] Preferably, the cooling unit comprises a non-contact denitration assembly 31 and a rapid cooling assembly connected with each other.

[0076] Preferably, the non-contact denitration assembly 31 is connected with the second combustion furnace 13 and can filter the nitrogen oxides in the mixed flue gas through a chemical solution.

[0077] Preferably, the chemical solution is ammonia water, sodium hydroxide solution, etc., which is not limited in the specification.

[0078] Preferably, the rapid cooling assembly can reduce the temperature of the mixed flue gas, and the rapid cooling assembly is connected with the filter scrubber, and the mixed flue gas after cooling can be transported to the filter scrubber.

[0079] Preferably, the rapid cooling assembly comprises a heat exchanger 32 and a quench tower 33. Of course, the rapid cooling assembly can also be of other structures, and the present specification is not limited again.

[0080] Preferably, the adsorber comprises a first adsorption member 41 and a second adsorption member 42.

[0081] Preferably, the first adsorption member 41 and the second adsorption member 42 are both connected with the filter scrubber through a connecting pipeline. Further preferably, the first adsorption member 41 and / or the second adsorption member 42 and / or the connecting pipeline are / is provided with a switch piece which can be opened or closed, and the change of the switch state of the switch piece can cause the mixed flue gas to switch between flowing to the first adsorption member 41 and flowing to the second adsorption member 42. That is to say, when the first adsorption member 41 adsorbs a certain amount of iodine, cesium, nitrogen oxides and the like, the switch piece can be adjusted to make the mixed flue gas flow to the second adsorption member 42 entirely, so as to replace the adsorbent of the first adsorption member 41.

[0082] Preferably, the dust-adsorbing unit 2 further comprises a flue gas cooler 38 and a gas-liquid separator 39.

[0083] Preferably, the flue gas cooler 38 and the gas-liquid separator 39 are arranged between the filter scrubber and the adsorber. The flue gas cooler 38 is connected with the filter scrubber, the flue gas cooler 38 is connected with the gas-liquid separator 39, and the gas-liquid separator 39 is connected with the adsorber.

[0084] Preferably, the flue gas cooler 38 is used to obtain the mixed flue gas transmitted from the filter scrubber and cool the mixed flue gas.

[0085] Preferably, the flue gas cooler 38 can reduce the temperature of the mixed flue gas to 0-5℃.

[0086] Preferably, the gas-liquid separator 39 can separate the water vapor in the mixed gas transmitted from the flue gas cooler 38 and transmit the mixed flue gas with separated water vapor to the adsorber. In this way, part of the water vapor mixed in the mixed flue gas in the filtering process can be separated and removed, reducing the influence of water vapor on the subsequent adsorption process.

[0087] Preferably, the concentration of water vapor in the mixed flue gas transmitted by the gas-liquid separator 39 to the adsorber is less than or equal to 100 mg / m 3 .

[0088] Preferably, the concentration of nitrogen oxides in the mixed flue gas flowing to the adsorber is 500-2500 Nm 3between 1000-3000 mg / Kg, and the concentration of cesium is between 2000-4000 mg / Kg.

[0089] Preferably, the adsorption efficiency of the adsorption material for the nitrogen oxide, the iodine and the cesium is greater than or equal to 90%.

[0090] Preferably, the adsorption material further comprises nano-palygorskite and / or malondialdehyde and / or triethanolamine.

[0091] Preferably, the system further comprises a solidification unit.

[0092] Preferably, the first combustion furnace 11 and / or the second combustion furnace 13 are further provided with an ash outlet 115, and the first combustion furnace 11 and the second combustion furnace 13 are further used to discharge the ash from the ash outlet 115.

[0093] Preferably, the solidification unit is used for cement solidification and / or high-temperature molten glass solidification of the ash.

[0094] Preferably, the feed inlet 112 of the first combustion furnace 11 is opened at the top.

[0095] Preferably, under the influence of the high-temperature active groups output by the plasma output assembly 113, at least part of the first combustion furnace 11 forms a gasification pyrolysis layer 114, which is divided into a drying layer, a pyrolysis layer, an oxidation layer and a slag layer from top to bottom, and the temperature gradually increases from 400°C to 1200°C from the drying layer to the slag layer.

[0096] Preferably, the plasma torch in the plasma output assembly 113 is powered by a high-power direct current power supply.

[0097] Preferably, the plasma output assembly 113 further comprises a cooling structure for cooling the plasma torch.

[0098] Preferably, the carrier wind output by the plasma output assembly 113 is air or water vapor.

[0099] Preferably, there are multiple air inlets 111.

[0100] Preferably, the multiple air inlets 111 are arranged in a ring shape. Figure 3 The structural schematic diagram of the air inlet 111 provided for an embodiment of the present specification is shown in Figure 3 The multiple air inlets 111 are arranged in a ring shape.

[0101] Preferably, the pyrolysis mixed gas comprises carbon monoxide, hydrogen, nitrogen oxide, etc.

[0102] Preferably, the position of the air inlet 111 corresponds to the pyrolysis layer.

[0103] Preferably, the inner wall of the first combustion furnace 11 and the second combustion furnace 13 is made of silicon nitride, silicon carbide, zirconium chromium corundum, or other refractory materials.

[0104] Preferably, the inner wall of the first combustion furnace 11 and the second combustion furnace 13 is made of silicon nitride, silicon carbide, zirconium chromium corundum, or other refractory materials.

[0105] Preferably, the surface temperature of the first combustion furnace 11 and the second combustion furnace 13 is 80-100℃.

[0106] Preferably, the connecting pipe 12 is further provided with a plurality of air inlets 111.

[0107] Preferably, among the plurality of air inlets 111 provided on the connecting pipe 12, at least one air inlet 111 is opened towards the vertically upward direction, and at least one air inlet 111 is opened towards the vertically downward direction, and the positions of the above two air inlets 111 correspond, as shown in the figure. Figure 3

[0108] Preferably, the temperature of the active radicals output by the plasma output assembly 113 towards the second combustion furnace 13 is 1500-2000℃.

[0109] Preferably, the number of air inlets 111 provided on the first combustion furnace 11 and the second combustion furnace 13 is 4-6.

[0110] Preferably, the heat exchanger 32 in the rapid cooling assembly can reduce the temperature of the mixed flue gas from 1100℃ to 600℃, and the quench tower 33 can reduce the temperature of the mixed flue gas from 600℃ to 150℃ within a preset time, thereby reducing the generation of dioxin.

[0111] Preferably, the filter scrubber comprises a filter and a scrubber.

[0112] Preferably, the filter comprises a first filter element 34 and a second filter element 35.

[0113] Preferably, the first filter element 34 and the second filter element 35 are connected to the second combustion furnace 13 through a connecting pipeline. Further preferably, the first filter element 34 and / or the second filter element 35 and / or the connecting pipeline is provided with a switch element, which can be opened or closed, and the change of the switch state of the switch element can cause the mixed flue gas to switch between flowing to the first filter element 34 and flowing to the second filter element 35. That is, when the first filter element 34 is filtered for a certain period of time, the mixed flue gas can be made to flow entirely to the second filter element 35 by adjusting the switch element, so as to replace the filter element of the first filter element 34. ​

[0114] Preferably, the first filter 34 and the second filter 35 are both provided with dust removal cloth bags.

[0115] Preferably, the scrubber comprises a first scrubbing tower 36 and a second scrubbing tower 37.

[0116] Preferably, the first scrubbing tower 36 and the second scrubbing tower 37 are connected in sequence.

[0117] Preferably, the nuclear waste treatment system further comprises an electric heater 43 and an induced draft fan 44.

[0118] Preferably, the electric heater 43 is connected with the dust removal and adsorption unit 2, and is used to heat the mixed flue gas after adsorption. In one or more embodiments provided in the present specification, the temperature of the mixed flue gas before adsorption is -5 to 0 degrees, and thus the electric heater 43 is needed to heat the mixed flue gas.

[0119] Preferably, the induced draft fan 44 is connected with the electric heater 43, and is used to output the heated mixed flue gas to a subsequent processing module.

[0120] Preferably, the mixed flue gas after adsorption meets the relevant emission requirements.

[0121] Figure 4 The structural schematic diagram of the nuclear waste treatment system provided in one embodiment of the present specification is shown in FIG. 1. Figure 4 As shown in FIG. 1, the first combustion furnace 11, the connecting pipe 12 and the second combustion furnace 13 are all provided with an air inlet 111, and the non-contact denitration assembly 31, the heat exchanger 32, the quench tower 33, the first filter 34 and the second filter 35 are connected in sequence and connected in parallel. The first scrubbing tower 36, the second scrubbing tower 37, the flue gas cooler 38 and the gas-liquid separator 39 are connected in sequence. The first adsorption unit 41 and the second adsorption unit 42 are connected in parallel. The electric heater 43 and the induced draft fan 44 are connected in sequence.

[0122] Table 1 is a statistical table of the adsorber temperature and the adsorption efficiency provided in one embodiment of the present specification, as shown in Table 1.

[0123] Table 1

[0124] Substance Adsorber temperature Adsorption efficiency Iodine 25 98.50％ Cesium 25 97.93％ Nitrogen oxides 25 98.25％ Iodine 0 99.39％ Cesium 0 98.80％ Nitrogen oxides 0 98.95％ Iodine -10 99.25％ Cesium -10 98.58％ Nitrogen oxides -10 99.30％

[0125] Therefore, in one or more embodiments of the present specification, before the mixed flue gas is adsorbed by the adsorber, the temperature of the mixed flue gas is adjusted to -5 to 0℃ by the flue gas cooler 38 in priority.

[0126] Studies have shown that catechin has good absorption effect on iodine and cesium. Table 2 is a statistical table of the adsorption effect of various adsorbents on iodine provided in one embodiment of the present specification, as shown in Table 2.

[0127] Table 2

[0128]

[0129] In the table, Catechin / ACF is a mixture of catechin and activated carbon. Obviously, the mixture of catechin and activated carbon has a stronger ability to capture iodine molecules than other adsorbents. Those skilled in the art can understand that the adsorbents listed in Table 2 are common adsorbents, and the present specification does not explain each adsorbent in Table 2.

[0130] Preferably, catechin is renewable and can be reused, which can reduce secondary pollution and reduce the negative impact on the environment.

[0131] Preferably, catechin can be extracted from natural plants and has high safety. When used as an adsorbent, it will not introduce new harmful substances and has low potential risk to the environment and human health.

[0132] Preferably, the structure of catechin itself is special, so that the adsorbent rich in catechin can have good mechanical strength and stability, which can meet the requirements of conventional use to ensure that it will not be broken or damaged due to physical action in the adsorption process.

[0133] Preferably, catechin contains multiple phenolic hydroxyl groups, which can partially ionize hydrogen ions. When the radionuclide exists in the form of a cation (for example, a cation formed by cesium), it can exchange with the ionized hydrogen ions of catechin, thereby achieving adsorption.

[0134] Preferably, the structural characteristics of catechin enable it to form a complex with radionuclides. The phenolic hydroxyl groups, carbonyl groups and other functional groups of catechin can act as coordination atoms to coordinate and complex with radionuclide ions. For example, for some transition metal radionuclides (such as actinides), catechin can form stable complexes with them through multiple functional groups. The stability of the complexation is related to the structure of catechin and the chemical properties of the radionuclide.

[0135] Preferably, catechin has a large specific surface area (for example, the specific surface area of ester-type catechin is ≥330m 2 / g), and radionuclide ions are adsorbed on the surface of catechin through intermolecular forces (such as van der Waals forces) when they are close to the surface of catechin in solution.

[0136] The above is the nuclear waste treatment system provided by one or more embodiments of the present specification. Based on the same idea, the present specification also provides a corresponding nuclear waste treatment method, as shown in Figure 5 .

[0137] Figure 5A flowchart of a method for nuclear waste treatment is provided for an embodiment of the present specification, as shown in Figure 5 The method comprises:

[0138] S900: In the first combustion furnace, the nuclear waste is preliminarily combusted by the exhaled high-temperature active groups of the plasma output assembly to generate pyrolysis mixed gas.

[0139] S902: In the second combustion furnace, the pyrolysis mixed gas is combusted by the exhaled high-temperature active groups of the plasma output assembly to generate mixed flue gas; the mixed flue gas at least includes nitrogen oxides, iodine and cesium.

[0140] S904: The macromolecular solid particles in the mixed flue gas are filtered by a filter scrubber, and the mixed flue gas is deacid washed.

[0141] S906: In the adsorber, the nitrogen oxides, iodine and cesium in the mixed flue gas are adsorbed by the adsorption material; the adsorption material includes catechin.

[0142] Preferably, before step S904 is performed, the method further comprises: filtering the nitrogen oxides in the mixed flue gas by a chemical solution in a non-contact denitration assembly, and cooling the mixed flue gas by a rapid cooling assembly.

[0143] It should be noted that all the actions of obtaining signals, information or data in the present application are carried out in accordance with the corresponding data protection regulations and policies of the country where the device is located, and with the authorization of the owner of the corresponding device.

[0144] In the 1990s, it was relatively easy to distinguish whether an improvement in a technology was a hardware improvement (e.g., an improvement in the circuit structure of a diode, transistor, switch, etc.) or a software improvement (an improvement in a method flow). However, as technology has evolved, many improvements in method flows today can be considered as direct improvements in hardware circuit structures. Designers almost always obtain the corresponding hardware circuit structures by programming the improved method flows into hardware circuits. Therefore, it cannot be said that an improvement in a method flow cannot be implemented using hardware entity modules. For example, a programmable logic device (PLD) (e.g., a field programmable gate array (FPGA)) is an integrated circuit whose logic function is determined by user programming of the device. A digital system is "integrated" on a PLD by the designer programming the PLD, rather than by ordering a custom integrated circuit chip from a chip fabricator. Moreover, instead of manually fabricating an integrated circuit chip, this programming is now mostly implemented using "logic compiler" software, which is similar to software compilers used in program development, and the original code to be compiled is written in a specific programming language, which is called a hardware description language (HDL), and there are many such languages, such as ABEL (Advanced Boolean Expression Language), AHDL (Altera Hardware Description Language), Confluence, CUPL (Cornell University Programming Language), HDCal, JHDL (Java Hardware Description Language), Lava, Lola, MyHDL, PALASM, RHDL (Ruby Hardware Description Language), etc., and the most commonly used are VHDL (Very-High-Speed Integrated Circuit Hardware Description Language) and Verilog. Those skilled in the art should be aware that, as long as the method flow is logically programmed and programmed into an integrated circuit using the above-mentioned hardware description languages, a hardware circuit that implements the logical method flow can be easily obtained.

[0145] The controller can be implemented in any suitable way, for example, the controller can take the form of a microprocessor or processor and a computer readable medium storing computer readable program code, such as software or firmware, executable by the (micro)processor, logic gates, switches, an application specific integrated circuit (ASIC), a programmable logic controller and an embedded microcontroller, examples of which include but are not limited to the following microcontrollers: ARC 625D, Atmel AT91SAM, Microchip PIC18F26K20 and Silicone Labs C8051F320, the memory controller can also be implemented as part of the control logic of the memory. Those skilled in the art will also know that, in addition to being implemented in pure computer readable program code, the controller can equally well be implemented to perform the same functions using logic gates, switches, an application specific integrated circuit, a programmable logic controller and an embedded microcontroller, etc. by means of a logical programming of the method steps. The controller can thus be considered as a hardware component, and the means comprised therein for performing the various functions can be considered as structures within the hardware component. Alternatively, the means for performing the various functions can even be considered as both a software module implementing the method and a structure within the hardware component.

[0146] The systems, apparatuses, modules or units illustrated by the above embodiments can be implemented by computer chips or entities, or by products with certain functions. A typical implementation device is a computer. Specifically, the computer can be a personal computer, a laptop computer, a cellular phone, a camera phone, a smart phone, a personal digital assistant, a media player, a navigation device, an email device, a game console, a tablet computer, a wearable device, or a combination of any of these devices.

[0147] For the sake of description, the above apparatuses are described in various units by functions respectively. Of course, the functions of each unit can be implemented in one or more software and / or hardware in the implementation of the present specification.

[0148] Those skilled in the art will understand that the embodiments of the present application can be provided as a method, a system or a computer program product. Therefore, the present application can take the form of a complete hardware embodiment, a complete software embodiment or an embodiment combining software and hardware aspects. Moreover, the present application can take the form of a computer program product implemented on one or more computer usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) containing computer usable program code.

[0149] The computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart block or blocks. Figure 1 one or more flowcharts and / or blocks in the flowcharts and / or combination thereof. Figure 1 one or more flowcharts and / or blocks in the flowcharts and / or combination thereof.

[0150] The computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart block or blocks. Figure 1 one or more flowcharts and / or blocks in the flowcharts and / or combination thereof. Figure 1 one or more flowcharts and / or blocks in the flowcharts and / or combination thereof.

[0151] The computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart block or blocks. Figure 1 one or more flowcharts and / or blocks in the flowcharts and / or combination thereof. Figure 1 one or more flowcharts and / or blocks in the flowcharts and / or combination thereof.

[0152] In one typical configuration, the computing device includes one or more processors (CPUs), input / output interfaces, network interfaces, and memory.

[0153] The memory can include non-persistent memory and / or volatile memory, such as random access memory (RAM) and / or cache memory, non-volatile memory, such as read-only memory (ROM), EPROM, and / or flash memory. The memory is an example of computer-readable media.

[0154] Computer-readable media includes permanent and non-permanent, movable and non-movable media that can be implemented by any method or technology to store information. The information can be computer-readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, compact disc read-only memory (CD-ROM), digital versatile disc (DVD) or other optical storage, magnetic cassette, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other non-transmission medium that can be used to store information accessible to a computing device. According to the definition herein, computer-readable media does not include transitory media such as modulated data signals and carriers.

[0155] It should also be noted that the terms "comprising", "comprising" or any other variant thereof are intended to cover non-exclusive inclusion, so that a process, method, article or apparatus that includes a list of elements not only includes those elements, but also includes other elements not explicitly listed or inherent to such process, method, article or apparatus. Without more limitations, the element defined by the statement "comprising a" does not exclude the presence of additional identical elements in the process, method, article or apparatus that includes the element.

[0156] Those skilled in the art will appreciate that embodiments of the present specification can be provided as methods, systems or computer program products. Therefore, the present specification can take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Moreover, the present specification can take the form of a computer program product implemented on one or more computer-usable storage media (including, but not limited to, magnetic disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0157] The present specification can be described in the general context of computer-executable instructions, such as program modules, executed by computers. Generally, program modules include routines, programs, objects, components, data structures, etc. that perform particular tasks or implement particular abstract data types. The present specification can also be practiced in distributed computing environments where tasks are performed by remote processing devices connected through a communication network. In a distributed computing environment, program modules can be located in both local and remote computer storage media, including storage devices.

[0158] The various embodiments described in this specification are intended to be exemplary only. The same features and aspects of the various embodiments can be combined in any combination. The various embodiments are described in the specification with reference to the drawings, in which:

[0159] The above description is embodied in the form of examples only and is not intended to limit the specification. The specification can be variously changed and modified by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the specification should be included in the scope of the claims of the present application.

Claims

1. A nuclear waste treatment system, the nuclear waste comprising cotton and / or resin and / or polyethylene, characterized in that, The nuclear waste treatment system comprises a plasma pyrolysis unit and a dust removal and adsorption unit; The plasma pyrolysis unit comprises a first combustion furnace, a connecting pipe, a second combustion furnace, an exhaust pipe and a plurality of plasma output assemblies; the connecting pipe is connected with the first combustion furnace and the second combustion furnace respectively; the first combustion furnace is provided with a feed inlet for filling nuclear waste; the plurality of plasma output assemblies are connected with the first combustion furnace and the second combustion furnace respectively and can output high-temperature active groups to the first combustion furnace and the second combustion furnace respectively; the nuclear waste can be preliminarily combusted and generate pyrolysis mixed gas under the action of the high-temperature active groups; the pyrolysis mixed gas transmitted into the second combustion furnace through the connecting pipe can be fully combusted and generate mixed flue gas under the action of the active groups; the mixed flue gas at least comprises nitrogen oxides, iodine and cesium; The dust removal and adsorption unit comprises a filter scrubber and an adsorber connected with each other; the filter scrubber is connected with the second combustion furnace and can remove dust and deacidify and wash the mixed flue gas; the adsorber is provided with adsorption materials for adsorbing the nitrogen oxides, iodine and cesium in the mixed flue gas by the adsorption materials; the adsorption materials comprise catechin.

2. The nuclear waste processing system of claim 1, wherein, The nuclear waste treatment system further comprises a denitration cooling unit; The denitration cooling unit is arranged between the plasma pyrolysis unit and the dust removal and adsorption unit; The cooling unit comprises a non-contact denitration assembly and a rapid cooling assembly connected with each other; The non-contact denitration assembly is connected with the second combustion furnace and can filter the nitrogen oxides in the mixed flue gas by a chemical solution; The rapid cooling assembly can reduce the temperature of the mixed flue gas, and the rapid cooling assembly is connected with the filter scrubber and can transport the mixed flue gas after temperature reduction to the filter scrubber.

3. The nuclear waste processing system of claim 1, wherein, The adsorber comprises a first adsorption subunit and a second adsorption subunit; The first adsorption subunit and the second adsorption subunit are both connected with the filter scrubber through a connecting pipeline; the first adsorption subunit and / or the second adsorption subunit and / or the connecting pipeline are provided with a switch piece; the switch piece can be opened or closed, and the change of the switch state of the switch piece can cause the mixed flue gas to switch between flowing to the first adsorption subunit and flowing to the second adsorption subunit.

4. The nuclear waste processing system of claim 1, wherein, The concentration of nitrogen oxides in the mixed flue gas flowing to the adsorber is between 500 and 2500 Nm 3 / h, the concentration of iodine is between 1000 and 3000 mg / Kg, and the concentration of cesium is between 2000 and 4000 mg / Kg. The adsorption efficiency of the adsorption materials for the nitrogen oxides, the iodine and the cesium is greater than or equal to 90%.

5. The nuclear waste processing system of any of claims 1-4, wherein, The adsorption materials further comprise nano-boehmite and / or malondialdehyde and / or triethanolamine.

6. The nuclear waste processing system of any one of claims 1-4, wherein, The system further comprises a solidification unit; The first combustion furnace and / or the second combustion furnace are further provided with an ash outlet; the first combustion furnace and the second combustion furnace are further used for discharging ash from the ash outlet; The solidification unit is used for cement solidification and / or high-temperature molten glass solidification of the ash.

7. The nuclear waste processing system of any one of claims 1-4, wherein, The dust removal and adsorption unit further comprises a gas-liquid separator; The gas-liquid separator is arranged between the filter scrubber and the adsorber, and is connected with the filter scrubber and the adsorber respectively, and is used for obtaining mixed flue gas transmitted from the filter scrubber, separating water vapor in the mixed flue gas, and transmitting the mixed flue gas with separated water vapor to the adsorber. The gas-liquid separator transmits the mixed flue gas with a water vapor concentration less than or equal to 100 mg / m 3 .

8. The nuclear waste processing system of any of claims 1-4, wherein, The first combustion furnace and / or the second combustion furnace is provided with an air inlet for adding combustion-supporting agent.

9. A method of nuclear waste processing, characterized by, The nuclear waste treatment system of any one of claims 1-8, comprising: In the first combustion furnace, the nuclear waste is preliminarily combusted by the high-temperature active groups exhaled by the plasma output assembly to generate pyrolysis mixed gas; In the second combustion furnace, the pyrolysis mixed gas is combusted by the high-temperature active groups exhaled by the plasma output assembly to generate mixed flue gas; the mixed flue gas at least includes nitrogen oxides, iodine and cesium; The macromolecular solid particles in the mixed flue gas are filtered by the filter scrubber, and the mixed flue gas is deacidic washed; In the adsorber, the nitrogen oxides, iodine and cesium in the mixed flue gas are adsorbed by the adsorption material; the adsorption material includes catechin.

10. The method of claim 9, wherein, Before the macromolecular solid particles in the mixed flue gas are filtered by the filter scrubber, the method further comprises: The nitrogen oxides in the mixed flue gas are filtered by the chemical solution in the non-contact denitration assembly; The mixed flue gas is cooled by the rapid cooling assembly.

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