APPARATUS FOR INJURING OR KILLING UNDESIRED ORGANISMS IN WATER

Abstract

An apparatus is for injuring or killing undesired organisms in water in a channel. The apparatus has an insert which is arranged to be releasably attached to the channel on the inside of the channel, a plurality of electrodes that are attached to the insert, the insert being formed from an electrically insulating material and the plurality of electrodes being connected to a power-supply unit. A method for using the apparatus in the channel is described as well.

Claims

1. An apparatus for injuring or killing undesired organisms in water in a channel, the apparatus comprising an insert configured to be releasably attached coupled to an inside of the channel, and a plurality of electrodes attached to the insert, wherein the insert is formed of an electrically insulating material and wherein the plurality of electrodes is connected to a power-supply unit.

2. The apparatus according to claim 1, wherein the insert is elongated with respect to a first longitudinal axis, wherein the electrode is elongated with respect to a second longitudinal axis, and wherein the second longitudinal axis is substantially parallel to the first longitudinal axis.

3. The apparatus according to claim 1, wherein the insert is elongated with respect to a first longitudinal axis, wherein the electrode is elongated with respect to a second longitudinal axis, and wherein the second longitudinal axis is substantially perpendicular to the first longitudinal axis.

4. The apparatus according to claim 1, wherein the insert comprises a first electrode holder and a second electrode holder.

5. The apparatus according claim 4, wherein the insert comprises at least one first spacer between the first electrode holder and the second electrode holder.

6. The apparatus according to claim 4, wherein the insert comprises an attachment device and a second spacer between the attachment device and the first electrode holder.

7. The apparatus according to claim 1, wherein an end portion of each electrode is configured to be connected to an electrical conductor.

8. A method for injuring or killing undesired organisms in water in a channel, the method comprising the steps of: a) providing an apparatus comprising an insert configured to be releasably coupled to an inside of the channel, and a plurality of electrodes attached to the insert, wherein the insert is formed of an electrically insulating material and wherein the plurality of electrodes is connected to a power-supply unit; b) connecting an electrical conductor to the end portion of each electrode in the plurality of electrodes; c) positioning the plurality of electrodes in the channel so that at least a portion of each electrode is submerged in the water in the channel; d) attaching the apparatus; e) connecting the plurality of electric electrodes to a direct-current supply, which includes a control unit, so that the electrodes are connected in pairs with a positive pole and a negative pole in each pair; and f) supplying a pulsed direct current to the electric electrodes.

9. The method according to claim 8, wherein the method, in step f), includes changing the polarity between pulses in the pulsed direct current.

10. The method according to claim 8, wherein the method, in step f), includes using a pulsed direct current at a voltage of between 12 V and 200 V.

11. The method according to claim 8, wherein the method, in step f), includes using a direct current at amperage of between 50 A and 200 A.

12. The apparatus according to claim 2, wherein an end portion of each electrode is configured to be connected to an electrical conductor.

13. The apparatus according to claim 3, wherein an end portion of each electrode is configured to be connected to an electrical conductor.

14. The apparatus according to claim 4, wherein an end portion of each electrode is configured to be connected to an electrical conductor.

15. The apparatus according to claim 5, wherein an end portion of each electrode is configured to be connected to an electrical conductor.

16. The apparatus according to claim 6, wherein an end portion of each electrode is configured to be connected to an electrical conductor.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In what follows, an example of a preferred embodiment is described, which is visualized in the accompanying drawings in which:

[0030] FIG. 1 shows a side view of the apparatus according to the invention;

[0031] FIG. 2 shows a view, on a larger scale, of the apparatus seen from one end; and

[0032] FIG. 3 shows a perspective view, on a different scale, of an alternative design of the apparatus.

DETAILED DESCRIPTION OF THE DRAWINGS

[0033] In the drawings, the reference numeral 1 indicates an apparatus which is arranged to be put into a channel 2 and taken out of the channel 2. The channel 2 is shown in FIG. 1 as a cylindrical pipe, but the channel 2 may also have other cross-sectional shapes, such as a square cross section. The apparatus 1 comprises a plurality of elongated electrodes 3 with longitudinal axes 83. The electrodes 3 are attached to an insert 4. The insert 4 forms a longitudinal axis 84. Each electrode 3 is connected to a power-supply unit (not shown) with an electrical conductor (not shown). The insert 4 consists of an electrically insulating material such as polyethene. The insert 4 is arranged to be attached internally in the channel 2.

[0034] In the embodiment that is shown in FIGS. 1 and 2, the insert 4 is formed with a first electrode holder 41 and a second electrode holder 42. The first electrode holder 41 and the second electrode holder 42 are shown formed as short cylinders with an outer diameter that is somewhat smaller than an inner diameter of the cylindrical channel 2.

[0035] The first electrode holder 41 is shown provided with a plurality of through axial openings 43. The second electrode holder 42 is shown provided with a plurality of axial recesses 45. The electrode 3 has been passed through the opening 43 and into the recess 45. The insert 4 further includes a plurality of first spacers 44 which connect the first electrode holder 41 axially to the second electrode holder 42.

[0036] The insert 4 further includes an attachment device 46. In FIGS. 1 and 2, the attachment device 46 is shown formed as a short cylinder with an outer diameter that is somewhat smaller than the inner diameter of the cylindrical channel 2. A plurality of second spacers 48 connect the first electrode holder 41 axially to the attachment device 46. The attachment device 46 is arranged to be attachable to the inside 20 of the channel 2, for example with screws.

[0037] In the figures, the electrodes 3 are shown positioned diagonally. With reference to FIG. 2, a first electrode group 33 is positioned at about “one o'clock” and “two o'clock” and a second electrode group 35 is positioned at about “seven o'clock” and “eight o'clock”. In another embodiment, the electrodes 3 may be positioned with approximately equal peripheral spacing of the electrodes 3 (not shown).

[0038] Each electrode 3 has a free end portion 31 projecting axially from the first electrode holder 41. An electrical conductor (not shown) is connected to the free end portion 31. A heat-shrinkable tubing (not shown) may cover the connection between the electrode 3 and the electrical conductor to prevent corrosion on the electrical conductor.

[0039] The electrodes 3 of the first electrode group 33 are connected in parallel to the power-supply unit. The electrodes 3 of the second electrode group 35 are connected in parallel to the power-supply unit, and the second electrode group 35 has opposite polarity to the first electrode group 33.

[0040] In other embodiments, each electrode group 33, 35 may comprise more than two electrodes 3. The apparatus 1 may include more than two electrode groups 33, 35, like four or six electrode groups, and each of these electrode groups may comprise two or more than two electrodes 3.

[0041] The insert 4 may be formed in different ways from that shown in the figures. In an alternative embodiment (not shown), the insert 4 may be formed of an elongated central stem with a longitudinal axis 84. A star-shaped first electrode holder 41 has a number of arms directed radially out from the stem. A star-shaped second electrode holder 42 has a number of arms directed radially out from the stem. An electrode 3 is attached to a free end portion of an arm in the first electrode holder 41 and to a free end portion of an arm in the second electrode holder 42 so that the longitudinal axis 83 of the electrode 3 is substantially parallel to the longitudinal axis 84 of the insert 4. The attachment device 46 may also be star-shaped with a number of arms that may be equal to or different from the number of arms of the first electrode holder 41.

[0042] The insert 4 is shown in a further alternative embodiment in FIG. 3. The apparatus 1 includes a plurality of elongated electrodes 3 with longitudinal axes 83. The electrodes 3 are attached to the insert 4. The insert 4 forms a longitudinal axis 84. Each electrode 3 is connected to a power-supply unit (not shown) with an electrical conductor (not shown). The insert 4 is formed from an electrically insulating material such as polyethene. The insert 4 is arranged to be attachable internally in the channel 2 (not shown in FIG. 3).

[0043] The insert 4 is formed with a first electrode holder 41 and a second electrode holder 42. The insert 4 further includes a plurality of first spacers 44 connecting the first electrode holder 41 to the second electrode holder 42. A plurality of spacers 48 connect the first electrode holder 41 and the second electrode holder 42 axially to the attachment device 46. The attachment device 46 is arranged to be attachable to the inside 20 of the channel 2, for example with screws.

[0044] In this embodiment, the longitudinal axis 83 of the electrode 3 is oriented substantially perpendicularly to the longitudinal axis 84 of the insert 4. The first electrode group 33 is positioned on one side of the insert 4, and the second electrode group 35 is positioned on the opposite side of the insert 4.

[0045] The channel 2 may be formed of a pipe extending from a closed facility (not shown) and down a water column (not shown). At a lower portion, the pipe is provided with an inlet (not shown). In an upper portion, the pipe is formed with a T-connection (not shown), and one branch of the T-connection extends substantially horizontally into the closed facility. A pump (not shown) is positioned in the upper portion of the pipe and below the T-connection. The T-connection also has a maintenance branch (not shown) projecting substantially vertically up from the T-connection.

[0046] Depending on the positioning of the pump in the pipe, the apparatus 1 is positioned internally in the pipe either above the pump or below the pump. When the pump is below the apparatus 1, the electrodes 3 are positioned below the horizontal branch of the T-connection, whereas the attachment device 46 is attached internally in the maintenance branch. When the pump is above the apparatus 1, the pump is first lifted out of the pipe through the maintenance branch, the attachment device 46 is attached internally in the pipe below the T-connection and the pump is put back into the pipe.

[0047] The apparatus 1 is arranged to injure or kill undesired organisms in water 9 entering the channel 2. Undesired organisms may be crustacean parasites, like salmon lice, in sea water 90. In particular, salmon lice may be in one of the three pelagic stages, the nauplius stages I and II and the copepodid stage. After having passed the apparatus 1, the salmon louse will not be able to infect salmonids.

[0048] Pulsed current with changing polarity has turned out to be well suited for the purpose. Direct current at a voltage of between 12 V and 200 V, at amperage of between 50 A and 200 A and with pulses lasting for 2 ms with breaks of 15-20 ms between the pulses is an example of a suitable regime.

[0049] It should be noted that all the above-mentioned embodiments illustrate the invention, but do not limit it, and persons skilled in the art may construct many alternative embodiments without departing from the scope of the attached claims. In the claims, reference numbers in brackets are not to be regarded as restrictive.

[0050] The use of the verb “to comprise” and its different forms does not exclude the presence of elements or steps that are not mentioned in the claims. The indefinite article “a” or “an” before an element does not exclude the presence of several such elements.

[0051] The fact that some features are indicated in mutually different dependent claims does not indicate that a combination of these features cannot be used with advantage.