Tank cleaning system

Description

1 / 15 TANK CLEANING SYSTEM PRIORITY CLAIM

[0001] This application claims priority over AU 2023900918, filed in Australia on 31 March 2023. The content of the priority application is incorporated by reference herein. TECHNICAL FIELD

[0002] The present invention relates generally to the field of storage, holding and other tanks, and more particularly to the field of tank cleaning. BACKGROUND

[0003] Underground mines generate large quantities of dust, powder, and other residual particles, which are often collected with water for extraction and cleaning purposes. The resulting shale and mud particles can be purified or pumped elsewhere, but first the suspended particles must be removed from suspension to ensure that downstream machinery is not damaged or clogged.

[0004] To achieve this goal, dirty water and sludge are typically collected in large chambered separation tanks (also known as hoppers). These are large tanks that are divided into chambers by internal weirs. The sludge is passed into the first chamber and left to reside (stand); the partially cleaned water passes through the weir, while the entrained particles sink to the bottom. The process is then repeated in each chamber sequentially, with the sludge and other entrained particulate matter being left in suspension each time, while the liquid passes through the weir to the next chamber. Eventually, the water that has been cleaned to a practical extent exits the tank through an outlet and can, in some cases, be recycled for reuse in production, collecting additional sludge.

[0005] Sludge tanks must be cleaned periodically. In previous systems, this involved opening drain valves at the base of each. Petition 870250108807, dated 11 / 27 / 2025, p. 5 / 28 2 / 15 chamber and manually break up, remove, and wash away the collected sludge and particulate matter. However, this can be risky with personnel entering in some cases and requires the cleaning crew to be trained to operate in confined spaces. The process also requires constant supervision due to the inherent risks, making it arduous, time-consuming, and taxing for the mine workforce. Finally, the process typically requires machinery such as drills, rotary hammers, and so on to break up the deposits, which may become cemented against the tank walls, presenting its own set of problems regarding equipment and power supply to the tank, as well as maneuvering the equipment within the confined space.

[0006] The present invention seeks to alleviate the risks and disadvantages of the prior art. DISCLOSURE OF THE INVENTION

[0007] In a first aspect, the present invention comprises a self-cleaning tank, comprising one or more chambers arranged sequentially and separated from each other by an overflow or spillway, an inlet opening to the first of one or more sequential chambers and an outlet opening to the last of one or more sequential chambers, the one or more chambers being non-pressurized, at least one drain associated with each of the one or more chambers, the inlet having an inlet valve and each of the at least one drain having a drain valve, the inlet valve and each of the drain valves being capable of being actuated separately between an open and a closed position, a plurality of spray nozzles arranged to spray fluid onto an internal surface of each of the one or more chambers, a fluid tube arranged to supply fluid to each of the plurality of spray nozzles,a fluid pipe flow control means associated with the fluid pipe suitable for controlling a fluid flow through the pipe and a control module connected to the fluid pipe flow control means, the valve, Petition 870250108807, dated 11 / 27 / 2025, page 6 / 28 3 / 15 of the inlet and each of the drain valves. In one embodiment, the plurality of spray nozzles is arranged at, near, or above an upper end of each of the one or more chambers, and each of the plurality of spray nozzles is configured to spray the fluid onto at least one internal surface of at least one of the one or more chambers.

[0008] In one embodiment, the plurality of spray nozzles is arranged in one or more nozzle assemblies, each of one or more sequential chambers with at least one of the one or more associated nozzle assemblies. In one embodiment, each nozzle assembly further comprises an assembly valve associated with them, which can be actuated between an open and a closed position, and the control module is connected to the assembly valve.

[0009] In one embodiment, the control module is configured to perform a tank cleaning process comprising, in any suitable order, the operations of: actuating the inlet valve to the closed position, actuating the drain valves of one or more chambers to the open position, transmitting a signal to the fluid pipe flow control means to supply fluid through the fluid pipe, in turn transmitting a signal to the fluid pipe flow control means to stop the fluid supply, actuating the drain valves to the closed position and actuating the inlet valve to the open position.

[0010] In one embodiment, the control module is configured to perform a tank cleaning process comprising, in any suitable order, the operations of: actuating the inlet valve to the closed position; transmitting a signal to the fluid pipe flow control means to supply fluid through the fluid pipe to each particular chamber of one or more chambers; actuating the drain valve associated with the drains of the particular chamber to the open position; actuating the assembly valve of the nozzle assemblies associated with the particular chamber to the open position at the appropriate time; actuating the assembly valve to the closed position; and actuating the valve of Petition 870250108807, dated 11 / 27 / 2025, p. 7 / 28 4 / 15 drain to the closed position; at the appropriate time, transmit a signal to the fluid pipe flow control means to interrupt the fluid supply and actuate the inlet valve to the open position. In one mode, the control module performs the operations for each particular chamber, one at a time. In one mode, the fluid is pressurized to at least 550 kPa.

[0011] A further aspect of the invention may be in a sludge retention and separation bank, comprising two or more self-cleaning tanks of an embodiment of the first aspect.

[0012] In one embodiment, the sludge retention and separation bank may comprise a common fluid pipe arranged to supply fluid to the nozzle assemblies of one or more of the two or more self-cleaning tanks. In another embodiment, the sludge retention and separation bank may comprise a common control module connected to the fluid pipe flow control means, the actuated inlet valve, and each of the actuated drain valves of one or more of the two or more self-cleaning tanks.

[0013] In one embodiment, the two or more self-cleaning tanks are arranged parallel to each other. In one embodiment, the two or more self-cleaning tanks are arranged in series. In one embodiment, there are three or more self-cleaning tanks, one or more of the three or more self-cleaning tanks are arranged parallel to each other, and one or more of the three or more self-cleaning tanks are arranged in series.

[0014] Additional or alternative embodiments of the invention may be disclosed herein or may become apparent to those skilled in the art through the disclosure presented herein. These and other embodiments are considered within the scope and subject matter of the invention. DESCRIPTION OF THE FIGURES

[0015] The embodiments of the present invention will now be described in relation to the Figures, where: Petition 870250108807, dated 11 / 27 / 2025, p. 8 / 28 5 / 15 Figure 1 represents an embodiment of a self-cleaning tank of the present invention; Figure 2 represents a four-chamber embodiment of the present invention; Figure 3 represents one embodiment of a nozzle assembly; Figure 4 illustrates a Process Flow Diagram of one embodiment of a self-cleaning tank of the present invention; Figures 5 to 7 illustrate different modalities of a cleaning process performed by an embodiment of the present invention; Figure 8 illustrates one embodiment of a sludge retention and separation bank; Figure 9 illustrates additional alternative embodiments of a sludge retention and separation bank; and Figure 10 illustrates an embodiment of a kit of the present invention. DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0016] In a first aspect and with reference to Figure 1, the present invention may comprise a self-cleaning tank 10, comprising at least two chambers 12 arranged sequentially and separated from each other by a weir 14, an inlet 16 opening into a first 12A of the at least two sequential chambers and having an inlet valve 18, an outlet 20 opening into a last 12B of the at least two sequential chambers, at least one drain 22 for each chamber 12 with a drain valve 24 installed thereon, a fluid pipe 26, a plurality of spray nozzles 28, a flow control means 30 and a control module 32. In one embodiment, the outlet 20 may have an outlet valve 34.

[0017] Those skilled in the art will understand that although Figure 1 depicts a tank 10 comprising only one pair of chambers, this is only an example and the tank may comprise any number of chambers 12 arranged in sequence. For example, Figure 2 depicts a tank Petition 870250108807, dated 11 / 27 / 2025, page 9 / 28 6 / 15 comprising four chambers 12. For clarity, Figure 2 does not represent the control module 32 or its connections.

[0018] In one embodiment, tank 10 may be a tank designed to retain or contain sludge and may be suitable for allowing the sludge to settle, at least partially, and / or separate, at least partially, into a clarified liquid and the suspended solid material. As used herein, the term sludge refers to solid particles mixed with liquid and includes liquid with entrained or suspended particulate matter, as well as deposits formed therefrom. Some non-limiting examples of sludge are clay, silt, marl or other earth and / or stone particles mixed with water; organic matter and soil suspended or carried by liquids, such as dirty or muddy water; drilling mud; runoff or wastewater containing particles from industrial processes such as mining and mineral processing; and any other liquid, suspension or deposit that would be called sludge by a person skilled in the art.

[0019] In one embodiment, the inlet valve 18 and each of the drain valves 24 (and the outlet valve 34, if present) can be in either an open or a closed position. In an open position, material can pass through inlet 16 or drain 22, respectively, while in a closed position, material cannot pass through them. With reference to Figure 1, inlet valve 18 and outlet valve 34 are plotted in the closed position, while drain valves 24 are plotted in the open position.

[0020] In one embodiment, the plurality of spray nozzles 28 may be arranged to receive fluid supplied by or through the fluid tube 26 and may comprise a plurality of nozzles arranged to spray the received fluid into at least two chambers 12. In a particular embodiment, several of the plurality of nozzles may be arranged to direct the fluid towards the internal walls or surfaces 12-1 of each Petition 870250108807, dated 11 / 27 / 2025, p. 10 / 28 7 / 15 chamber 12. The fluid can be water or a cleaning fluid. The inner surface 12-1 can be a spillway surface 14. The water can be 'dirty' or mine water.

[0021] In one embodiment, the tank 10 is a non-pressurized container. In a further embodiment, one or more chambers 12 are open at the top, and at least a plurality of spray nozzles 28 may be arranged in, near, or above an upper end 122 of each of the one or more chambers 12. In one embodiment, the plurality of spray nozzles 28 is configured to spray the fluid onto the respective internal surface 12-1 of one or more chambers 12. In a further embodiment, the spray nozzles 28 are arranged and suitable for spraying the fluid to optimally dislodge, break up, and remove solids that have deposited or adhered to the chamber walls or internal surfaces 12-1.

[0022] In an additional embodiment, the fluid is pressurized to at least 550 kPa. In another embodiment, the number of spray nozzles 28 that are used simultaneously may be directly proportional to the pressure of the supplied fluid. High pressure is considered necessary to reduce the time for dislodging, breaking up and removing solids that have settled or adhered to the chamber walls. Thus, in embodiments where the fluid is supplied at a reduced pressure, the self-cleaning tank 10 may need to conduct multiple cleaning cycles and / or clean the individual chambers 12 in stages to ensure that the chambers 12 are thoroughly cleaned.

[0023] In one embodiment, the control module 32 is connected to the flow control medium 30, to the inlet valve 18 (and to the outlet valve 34, if present) and to each of the drain valves 24. The control module can be configured to run at least one cleaning, operation or subroutine program and may be able to control and / or actuate the fluid pipe flow control medium 30, the inlet valve 18 (and the outlet valve 34, if present) Petition 870250108807, dated 11 / 27 / 2025, page 11 / 28 8 / 15 present) and each of the 24 drain valves. In an additional embodiment, the control module 32 can be configured to be automated.

[0024] In one embodiment, the flow control means 30 may be a pump that pumps fluid into the fluid pipe 26. In an alternative embodiment, the flow control means 30 may be a valve with an open position and a closed position. Those skilled in the art will understand that there may be other forms of fluid flow control known in the art, and their use does not depart from the scope or purpose thereof.

[0025] In one embodiment, the control module 32 can be additionally connected to a plurality of spray nozzles 28. In a further embodiment, one or more nozzles of the nozzle set can be adjustable in at least one parameter thereof, such as spray direction, spray pattern, spray intensity, etc. The control module 32 can be configured to control the adjustment of one or more nozzles. In a further embodiment, the control module can be adapted to receive manual input to control the adjustment of one or more nozzles.

[0026] In one embodiment and with reference to Figure 6, the plurality of spray nozzles 28 may be arranged in one or more nozzle sets 28-1, wherein each of the one or more sequential chambers 12 has at least one of the one or more nozzle sets 28-1 associated with it. The nozzle set 28-1 may be suitable for spraying fluid into at least one of the two chambers 12. In a further embodiment, the tank 10 may comprise separate nozzle sets 28-1 for each chamber 12. In an alternative (but not exclusive) embodiment, there may be a plurality of nozzle sets arranged to spray fluid into various parts of the same chamber 12. In a further embodiment and with reference to Figure 3, the nozzle sets may further comprise a valve set 36 that can be actuated between an open and a closed position. In a further embodiment, the control module 32 may be connected to the valve of Petition 870250108807, dated 11 / 27 / 2025, page 12 / 28 9 / 15 assembly 36. Control module 32 may be suitable for actuating valves of assembly 36, one from another, separately and independently. In Figure 6, the control wires are only partially represented for clarity; however, those skilled in the art will realize that the control wires extend between control module 32 and each component controlled by it.

[0027] In one embodiment, the control module 32 can be configured with multiple cleaning and drainage programs to handle different situations. For example, in an embodiment where mud and other solids are heavily deposited, the control module can activate a single set of nozzles 28-1 at a time to maximize the pressure – and therefore the cleaning capacity – of the sprayed cleaning fluid.

[0028] In addition, if mine process conditions change and the tank becomes full, the system has a high-level alarm that will trigger additional automated cleanings. Due to the specific height and positioning of the nozzle assembly, the system will still perform an effective, albeit longer, cleaning cycle.

[0029] In one embodiment, the self-cleaning tank 10 may comprise a plurality of fluid tubes 26, each in fluid communication with at least one plurality of spray nozzles 28, or at least one of the nozzle sets 28-1, or both, depending on which embodiment of at least one plurality of spray nozzles 28 is present. Each of the various fluid tubes 26 may comprise separate flow control means 30, and each separate flow control means may be operated independently by the control module 32.

[0030] In one embodiment and with reference to Figure 5, control module 32 is configured to perform a tank cleaning process. The tank cleaning process may comprise, in any suitable order, the following operations: (a) activate inlet valve 18 to the closed position; (b) activate drain valves 24 to the open position; Petition 870250108807, dated 11 / 27 / 2025, page 13 / 28 10 / 15 (c) transmit a signal to the flow control medium 30 to supply fluid through the fluid tube 26; (d) in turn, transmit a signal to the flow control medium 30 to interrupt the fluid supply through the fluid pipe 26; (e) activate drain valves 24 to the closed position; and (f) activate inlet valve 18 to the open position.

[0031] In an embodiment wherein the self-cleaning tank 10 comprises an outlet valve 34 within the outlet 20, operation (a) of the tank cleaning program may further comprise actuating the outlet valve 34 to the closed position, and operation (f) may further comprise actuating the outlet valve 34 to the open position.

[0032] In an embodiment wherein the self-cleaning tank 10 comprises sets of nozzles 28-1 associated with separate chambers 12, and with reference to Figure 6, the control module 32 may be suitable for performing a tank cleaning process for one or a few particular chambers 12 at a time. The tank cleaning process may comprise, in any suitable order, the operations of: (a) actuate inlet valve 18 (and outlet valve 34, if present) to the closed position; (b) transmit a signal to the flow control medium 30 to supply fluid through the fluid tube 26; (c) for each particular chamber: (i) activate the drain valve 24 of the private chamber 12 to the open position; (ii) activate the valve of assembly 36 of the nozzle assembly(ies) 28-1 that is / are arranged to spray fluid into the particular chamber to the open position; (iii) At the appropriate time, actuate the assembly valve 36 to the closed position; and Petition 870250108807, dated 11 / 27 / 2025, page 14 / 28 11 / 15 (iv) activate drain valve 24 to the closed position; (d) at the appropriate time, transmit a signal to the flow control means 30 to interrupt the fluid supply; and (e) actuate the inlet valve 18 (and the outlet valve 34, if present) to the open position.

[0033] In an alternative embodiment and with reference to Figure 7, all drain valves 24 can be actuated to the open position before step (c) (i.e., step (c) begins with substep (ii)), and / or all drain valves 24 can be actuated to the closed position after step (c) (i.e., step (c) ends with substep (iii)).

[0034] In a further embodiment, operations (c)(i) - (c)(iv) are conducted for one chamber 12 at a time, or simultaneously for only some chambers 12, i.e., not all valve sets 36 are opened at the same time. By way of non-limiting example, in a self-cleaning tank 10 comprising four chambers 12, each with its own set of nozzles, the nozzle sets of the first and second chambers may be activated (valves open) at the same time and deactivated (valves closed) before the nozzle sets of the third and fourth chambers are activated. Alternatively, only the nozzle sets 28-1 associated with one of the four chambers 12 may be opened at a time.These arrangements may be beneficial for embodiments in which, for example, the pressure or flow rate of the fluid supplied by the flow control means 30 to the fluid tube(s) 26 is / are insufficient to adequately clean all chambers 12 within the self-cleaning tank 10 at the same time. In a further embodiment, operations (c)(i) - (c)(iv) are conducted separately for each chamber 12 in the two or more chambers 12.

[0035] In a further embodiment, instead of operation (c)(i) being conducted for each tank sequentially, the tank cleaning process may comprise an operation, prior to operation (c), in which some or all of the valves in the nozzle assembly 36 are opened. In an embodiment Petition 870250108807, dated 11 / 27 / 2025, p. 15 / 28 12 / 15 additionally, instead of operation (c)(iv) being conducted for each tank sequentially, the tank cleaning process may comprise an operation, after the completion of operation (c), in which some or all of the valves in the nozzle assembly 36 are closed.

[0036] A second aspect of the invention, and with reference to Figure 8, may consist of a sludge retention and separation bank 100, comprising two or more self-cleaning tanks 10-1, 10-2 according to any of the embodiments above. Figure 8 omits certain elements and abstracts others for clarity, but the person skilled in the art will realize that these elements are still present. For example, the control module 32 is represented as connected to each self-cleaning tank 10-1, 10-2, but the person skilled in the art will understand that these are connections to the inlet valves 16, drains 22 and outlets 20 (if present). Similarly, the fluid pipe 26 is represented simply as entering each self-cleaning tank 10-1, 10-2, but the person skilled in the art will understand that in each case there is one or more nozzle sets 28 and / or sets 28-1 being supplied.

[0037] In one embodiment, the sludge retention and separation bank 100 may comprise a common fluid pipe 26, arranged to supply fluid to the nozzle assemblies 28 of at least two of the two or more self-cleaning tanks 10-1 and 10-2. In an alternative embodiment, at least one of the two or more self-cleaning tanks 10-1 and 10-2 may have its own fluid pipe 26. This may be beneficial in embodiments where, for example, one of the self-cleaning tanks requires more frequent cleaning or cleaning at a higher pressure than the other tanks in the sludge retention and separation bank 100.

[0038] In one embodiment, the sludge retention and separation bank 100 may comprise a common control module 32 connected to the flow control means 30, to the inlet valve 18 (and to the outlet valve 34, if present) and to each of the drain valves 24 of at least two of the two or more self-cleaning tanks 10-1 and 10-2. Petition 870250108807, dated 11 / 27 / 2025, p. 16 / 28 13 / 15

[0039] In one embodiment, two or more self-cleaning tanks 10-1, 10-2 within the sludge retention and separation bank 100 may be arranged in parallel to each other. In such an embodiment, these two or more self-cleaning tanks 10-1, 10-2 receive input, through their respective inlets 16, from the same source. In an alternative, but not exclusive, embodiment, two or more self-cleaning tanks 10-1, 10-2 within the sludge retention and separation bank 100 may be arranged in series, such that the outlet 20 of one of the self-cleaning tanks is connected to the inlet 16 of the next.

[0040] In a further embodiment of both non-exclusive alternative embodiments discussed immediately above, the sludge retention and separation bank 100 may comprise three or more self-cleaning tanks 10-1, 10-2, 10-3, wherein some of the self-cleaning tanks are arranged in series with each other and some of the self-cleaning tanks are arranged in parallel. Figure 9 illustrates two possible arrangements of the aforementioned embodiment, being a first sludge retention and separation bank 100A and a second sludge retention and separation bank 100B. In further embodiments, a particular self-cleaning tank within the sludge retention and separation bank may be in parallel with one or more self-cleaning tanks and may be in series with one or more other self-cleaning tanks within the sludge retention and separation bank.

[0041] A further aspect of the invention may be a self-cleaning conversion kit for retrofitting a prior art sludge holding tank, comprising one or more internal chambers in an embodiment of the first aspect of the invention. In one embodiment and with reference to Figure 10, the kit 100 may comprise a fluid tube 102, a plurality of spray nozzles 104, a drain valve 106 for each drain within the tank, a flow control means 110 and a control module 112. In one embodiment, the kit may further comprise an inlet valve 114 and / or an outlet valve 116. In embodiments Petition 870250108807, dated 11 / 27 / 2025, p. 17 / 28 In additional embodiments, the kit may comprise one or more nozzle assemblies 104-1 comprising a valve assembly 118. The control module 112 may be connectable to it and have the capability to actuate the valve 118. In a further embodiment, the kit 100 may comprise one or more mountable brackets 120 at an upper end of the tank for mounting the plurality of nozzles 104 and / or nozzle assemblies 104-1 to it.

[0042] Although the invention has been described with reference to the preferred embodiments above, those skilled in the art will understand that it is not limited to those embodiments and may be incorporated in many other forms, variations and modifications beyond those specifically described. The invention includes all such variations and modifications. The invention also includes all steps, features, components and / or devices mentioned or indicated in the descriptive report, individually or collectively, and any and all combinations of, or any two or more of, such steps or features.

[0043] In this descriptive report, unless the context clearly indicates otherwise, the word comprehending is not intended to have the exclusive meaning of the word, as consisting only of, but rather the non-exclusive meaning, in the sense of including at least. The same applies, with the corresponding grammatical changes, to other forms of the word, such as comprehending, etc.

[0044] Other definitions for selected terms used in this document can be found in the detailed description of the invention and apply throughout the document. Unless defined otherwise, all other scientific and technical terms used in this document have the same meaning commonly understood by a person skilled in the art to which the invention pertains.

[0045] Any warranties made in this document should be understood as relating to some embodiments of the invention and are not intended to be warranties about the invention in all embodiments. Where Petition 870250108807, dated 11 / 27 / 2025, p. 18 / 28 15 / 15 If there are warranties that are considered applicable to all embodiments of the invention, the applicant / patent holder reserves the right to subsequently exclude them from the description and does not rely on these warranties for the subsequent acceptance or granting of a patent in any country. Petition 870250108807, dated 11 / 27 / 2025, pp. 19 / 28

Claims

1 / 4 CLAIMS 1. Self-cleaning tank, characterized by comprising: two or more chambers arranged in sequence and separated from each other by a weir or overflow, an inlet opening into one of the first two or more sequential chambers and an outlet opening into one of the last two or more sequential chambers, each of the two or more chambers being non-pressurized; at least one drain associated with each of the two or more chambers; the inlet with an inlet valve, and each of the at least one drains with a drain valve, the inlet valve and each of the drain valves capable of being actuated separately between an open and a closed position; a plurality of spray nozzles arranged to spray fluid onto an internal surface of each of the two or more chambers; a fluid pipe arranged to supply fluid to each of the plurality of spray nozzles;a fluid pipe flow control means associated with the fluid pipe adapted to control a fluid flow through the pipe; and a control module connected to the fluid pipe flow control means, the inlet valve and each of the drain valves.

2. Self-cleaning tank, according to claim 1, characterized in that a plurality of spray nozzles are arranged at, near, or above an upper end of each of two or more chambers; and each of the plurality of spray nozzles is configured to spray the fluid onto at least one internal surface of at least one of the two or more chambers.

3. Self-cleaning tank, according to claim 1, characterized by the plurality of spray nozzles being arranged in one or more sets of nozzles, each of the two or more sequential chambers with at least one of the one or more sets of nozzles associated with them.

4. Self-cleaning tank, according to claim 3, characterized in that each set of nozzles further comprises an assembly valve associated with them which can be actuated between an open position and a closed position; and the control module is connected to the assembly valve.

5. Self-cleaning tank, according to claim 1, characterized in that the control module is configured to perform a tank cleaning process, comprising the operations of: actuating the inlet valve to the closed position; actuating the drain valves of the two or more chambers to the open position; transmitting a signal to the fluid tube flow control means to supply fluid through the fluid tube; in turn, transmitting a signal to the fluid tube flow control means to stop the fluid supply; actuating the drain valves to the closed position; and actuating the inlet valve to the open position.

6. Self-cleaning tank, according to claim 4, characterized in that the control module is configured to perform a tank cleaning process, comprising the operations of: actuating the inlet valve to the closed position; transmitting a signal to the fluid tube flow control means to supply fluid through the fluid tube; for each specific chamber of the two or more chambers: actuating the drain valve associated with the drains of the particular chamber to the open position; actuating the nozzle assembly valve associated with the particular chamber to the open position; Petition 870250088596, dated 09 / 30 / 2025, page 64 / 66 3 / 4 in due time, actuating the assembly valve to the closed position; and actuating the drain valve to the closed position; in due time, transmitting a signal to the fluid tube flow control means to interrupt the fluid supply; and actuating the inlet valve to the open position.

7. Self-cleaning tank, according to claim 6, characterized by the control module performing the operations for each specific chamber at a time.

8. Self-cleaning tank, according to claim 1, characterized in that the fluid is pressurized to at least 550 kPa.

9. Sludge retention and separation bank, as defined in claim 1, characterized in that the fluid sprayed onto the inner surface of each of the two or more chambers is water.

10. Sludge retention and separation bank, according to claim 9, characterized by the water being "dirty" or mining water.

11. Sludge retention and separation bank, characterized by comprising three or more self-cleaning tanks, as defined in claim 1.

12. Sludge retention and separation bank, according to claim 11, characterized by comprising a common fluid pipe arranged to supply fluid to the nozzle assemblies of two or more of the three or more self-cleaning tanks.

13. Sludge retention and separation bank, according to claim 11, characterized by comprising a common control module connected to the fluid pipe flow control means, to the actuatable inlet valve and to each of the actuatable drain valves of two or more of the three or more self-cleaning tanks.

14. Sludge retention and separation bank, as per Petition 870250088596, dated 09 / 30 / 2025, pp. 65 / 66 4 / 4 claim 11, characterized by three or more self-cleaning tanks being arranged in parallel to each other.

15. Sludge retention and separation bank, according to claim 11, characterized by three or more self-cleaning tanks being arranged in series.

16. Sludge retention and separation bank, according to claim 11, characterized by having four or more self-cleaning tanks; two or more of the four or more self-cleaning tanks being arranged in parallel; and two or more of the four or more self-cleaning tanks being arranged in series. Petition 870250088596, dated 09 / 30 / 2025, p. 66 / 66

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