METHOD AND ARRANGEMENT FOR CLEANING LIQUID

Abstract

The invention relates to a method and an arrangement for operating a system in which dismantling works are performed underwater in a liquid-filled vessel (10) of a nuclear facility, the liquid being guided in a circuit (20) and flowing through at least one filter device (26, 28, 30). The liquid in the circuit flows through at least a first filter device (26) in the form of a coarse filter and a second filter device (28), in which at least one device from the group of ion exchangers (1, 2, 3), reverse osmosis systems, ultrafiltration systems, activated carbon filters, zeolite filters, and biological filters is used for filtration.

Claims

1. A method for operating a system in which dismantling works are performed underwater in a liquid-filled vessel (10) of a nuclear facility, such as a reactor pressure vessel or fuel element well or a reactor well, wherein the liquid is guided in a circuit (20, 200) and flows through at least one filter device (26, 28, 30), characterized in that the liquid in the circuit (20, 200) flows through at least one first filter device (26) in the form of a coarse filter and one second filter device (28), in which at least one device from the group comprising ion exchangers (1, 2, 3), reverse osmosis systems, ultrafiltration systems, activated carbon filters, zeolite filters, and biological filters is used for filtration, and in that the first and/or the second filter device is arranged in the vessel (10).

2. The method according to claim 1, characterized in that the liquid flows through the first filter device (26) and a further filter device (30) arranged downstream thereof before flowing through the second filter device (28).

3. The method according to claim 1, characterized in that a coarse filter, particularly a perforated cylinder, wire mesh filter, or filter cartridge is used as the first filter device (26), particularly with a filter fineness between 1 mm and 5 mm, and/or a fine filter, particularly one or more fine filter cartridges, wound filter cartridges, or metal-edge filters are used as the further filter device (30), particularly with a filter fineness between 1 μm and 150 μm.

4. The method according to claim 1, characterized in that the second filter device (28) comprises several ion exchangers (1, 2, 3), which are arranged fluidically in parallel and/or in series.

5. The method according to claim 1, characterized in that the first filter device (26) is arranged within the vessel (10) and the second filter device (28) is arranged outside the vessel.

6. An underwater dismantling arrangement, comprising a liquid-filled vessel (10) of a nuclear facility, such as a reactor pressure vessel or fuel element well or reactor well, as well as a liquid circuit (20, 200) enclosing the vessel, in which circuit at least one filter device (26, 28, 30) is arranged, characterized in that at least one first and one second filter device (26, 28) are arranged in the circuit (20, 200), in that the first filter device (26) is a coarse filter, and the second filter device (28) is a device from the group comprising ion exchangers (1, 2, 3), reverse osmosis systems, ultrafiltration systems, zeolite filters, activated carbon filters, and biological filters, and in that the first and/or the second filter device is or are arranged in the vessel (10).

7. The arrangement according to claim 6, characterized in that a further filter device (30) is arranged upstream of the second filter device (28) in the circuit (20, 200).

8. The arrangement according to claim 6, characterized in that the first filter device (26) is a coarse filter, particularly a perforated cylinder, wire mesh filter, or filter cartridge, particularly with a filter fineness between 1 mm and 5 mm, and/or the further filter device (30) is a fine filter, particularly one or more fine filter cartridges, wound filter cartridges, or metal-edge filters, particularly with a filter fineness between 1 μm and 150 μm.

9. The arrangement according to claim 6, characterized in that the second filter device (28) has at least two ion exchangers (1, 2, 3), which are used fluidically in series or in parallel.

10. The arrangement according to claim 6, characterized in that the second filter device (28) is or comprises at least one ion exchanger from the group comprising radionuclide-selective ion exchangers, anion exchangers, or cation exchangers.

11. The arrangement according to claim 6, characterized in that the first filter device (26) is arranged within the vessel (10) and the second filter device (28) is arranged outside the vessel.

Description

[0040] Further details, advantages, and features of the invention result not only from the claims, the features to be taken from said claims—on their own and/or in combination—as well as the exemplary embodiments to be obtained from the following description of the drawing.

[0041] The following is shown:

[0042] FIG. 1 a first exemplary embodiment of an underwater dismantling arrangement; and

[0043] FIG. 2 a second embodiment of an underwater dismantling arrangement.

[0044] FIG. 1 shows, as a first exemplary embodiment of the teaching according to the invention, a section of a water-filled vessel 10 of a nuclear facility, such as reactor wells, in which underwater dismantling works are carried out. These dismantling works are carried out remotely, inter alia, by means of video technology. Purely as an example, FIG. 1 shows two video cameras 12, 14 which provide images of an object 16 to be dismantled, which is dismantled by means of a tool 18. The liquid, i.e. the water, flows through several filter devices so that the view is not negatively impacted, e.g. due to turbidity of the water, so that there can be trouble-free control of the dismantling tool, optionally automatically, using the images obtained from the video cameras 12, 14. According to the invention, the water is routed within the vessel 10 in a circuit 20 in this case.

[0045] An intake port 22 is situated in the liquid in order to suction the liquid using a pump 24 so that the suctioned liquid can flow through the circuit 20. The circuit 20 contains a coarse filter 26 as the first filter device, a second filter device 28 of the embodiment as described subsequently, as well as a further filter device 30, which is a fine filter, arranged in the circuit between the first filter device 26 and the second filter device 28.

[0046] Particles a size of, e.g., 1 mm to 5 mm and greater are filtered out by means of the first filter device, i.e. the coarse filter 26.

[0047] The coarse filter 26 is particularly a perforated cylinder, wire mesh filter, or one or more filter cartridges or combinations of several of these filters.

[0048] The fine filter 30 arranged downstream of the coarse filter 26 in the circuit 20 should have one or more fine filter cartridges and/or one or more wound filter cartridges, or one or more metal-edge filters in order to enable fine filtering of particles of up to 150 μm.

[0049] The fine filter 30 can also be one or more activated carbon cartridges.

[0050] The second filter device 28 is arranged downstream of the fine filter 30 in the circuit 20; in the exemplary embodiment, this filter device comprises three individual filters used in parallel: a radionuclide-selective ion exchanger 1, an anion exchanger 2, as well as a cation exchanger 3. It is also possible to replace one or more of the ion exchangers, e.g., with an activated carbon filter and/or zeolite filter and/or ultrafiltration system and/or reverse osmosis system and/or biological filter or to consider these in a supplemental manner.

[0051] If the filters 1, 2, 3 in the exemplary embodiment are used in parallel, an arrangement in series or also a combination of parallel and series arrangements are possible.

[0052] The outlet (arrow 32) of the second filter device 28 opens into the vessel liquid, resulting in the circuit 20.

[0053] The second filter device 28 provides the advantage that particularly metal ions, such as iron ions, chromium ions, nickel ions, manganese ions, as well as radionuclides can be filtered out.

[0054] Microorganisms and harmful substances can also be filtered out. These measures prevent turbidity of the water and the accumulation of harmful substances in the vessel 10.

[0055] The flow particularly through the second filter device 28 ensures good water quality which prevents breeding grounds for the growth of microorganisms or algae from being formed.

[0056] Thus, a trouble-free dismantling operation is possible.

[0057] FIG. 2 shows a second exemplary embodiment, which is an arrangement for the underwater dismantling of components, particularly in a nuclear facility. In this case, the same reference numerals are used for the same elements in accordance with FIG. 1.

[0058] According to the exemplary embodiment in FIG. 2 as well, the liquid present in the wells 10 is guided in a circuit 200, wherein the first filter device 26 and the further filter device 30 are arranged in the vessel 10 and the second filter device 28 is arranged outside the vessel 10, which is obvious from FIG. 2 and deviates from FIG. 1. Otherwise, the procedure and the liquid circuit are the same in order to prevent negatively impacting the viewing conditions as well as an accumulation of harmful substances in the liquid during the underwater dismantling works. In order to achieve this, the liquid is suctioned via the intake port 22 by means of the pump 24 so that the liquid can flow in the circuit 200 in which the first filter device 26 and the further filter device 30 are located, and that is within the vessel 10, in order to then guide the circuit 200 out of the vessel 10 and enable the liquid to flow through the second filter device 28. Subsequently, the circuit is guided back into the vessel 10. The types of filter devices 26, 28, 30 correspond to those which have been explained in connection with FIG. 1 such that reference is made to the embodiments related thereto.