Water treatment

Abstract

A non-sacrificial core 12 for a water treatment device 1, the core comprises at least two ridges 12a, 12b, 12c, each ridge extending away from a longitudinal axis of the core and extending along at le

Description

TECHNICAL FIELD The invention relates to a core for a water treatment device and a water treatment device, and in particular to a non-sacrificial core for a water treatment device. BACKGROUND Water treatment and water conditioning have long been essential aspects of modern society, as they ensure the availability of clean and safe water for various applications, including domestic, industrial, and agricultural uses. One of the primary challenges in water treatment is the management and prevention of scale formation, particularly limescale, which is caused by the precipitation of minerals such as calcium carbonate. Hard water is particularly problematic due to the larger concentration of limescale forming minerals. Limescale buildup can lead to reduced efficiency and performance of water systems, as well as increased maintenance costs and potential damage to equipment and infrastructure. Various water treatment devices and methods have been developed to address the issue of scale formation. Typical methods include the use of chemical additives, such as water softeners, which can be effective in reducing scale buildup but may introduce undesirable chemicals into the water supply. Additionally, these methods often require regular maintenance and replenishment of the chemical additives, which can be both costly and time-consuming. Another approach to water treatment involves the use of physical water conditioning devices, which typically employ mechanisms to alter the behaviour of minerals within the water flow, thereby reducing the likelihood of scale formation. These devices may include sacrificial anodes, which are designed to corrode preferentially, thereby protecting other components within the water system from corrosion and scale buildup. However, these systems often have limited lifespans and may require frequent replacement or maintenance, as well as potentially introducing undesirable materials into the water flow. 06 03 24 Improvements are desired to overcome shortcomings of existing implementations, such as enhancing the efficiency and effectiveness of scale prevention, reducing maintenance requirements, and extending the lifespan of water treatment devices and downstream components. 5 SUMMARY According to a first aspect, there is provided a non-sacrificial core for a water treatment device in accordance with independent claim 1. Some optional or preferred features are set out in 10 dependent claims. Advantageously, this may effectively prevent limescale buildup and enhance the performance and lifespan of downstream components and water heating devices by generating ionic interactions that keep mineral precipitates dispersed within the fluid flow. 15 A non-sacrificial core comprising a metallic or metal alloy material configured such that mineral ions within the water precipitate to provide a colloidal dispersion may advantageously provide a long-lasting and effective scale prevention without the need for regular maintenance or the introduction of additional materials into the water supply. This is in contrast to traditional 20 sacrificial anodes, which degrade over time and release metal ions into the water. A non-sacrificial core may promote the formation of mineral precipitates within the water flow, which can then be more easily removed or managed, rather than allowing them to accumulate on surfaces within the water system. 25 The non-sacrificial nature of the core material ensures that the water treatment device may remain effective in preventing limescale buildup and promoting mineral precipitation without introducing additional contaminants into the water supply. This prevention of mineral precipitation onto surfaces is crucial in reducing limescale buildup 30 upon downstream components such as faucets, taps, showerheads, and other pipes. Limescale buildup can lead to reduced water flow, increased maintenance costs, and decreased efficiency of water heating devices. By preventing limescale formation, the water treatment device may effectively extend the lifespan of these downstream components, reducing the need for frequent replacements and maintenance. Furthermore, the prevention of limescale buildup and the promotion of mineral precipitation within the fluid flow may directly improve the performance of water heating devices such as instantaneous water heaters and electric showers. Limescale buildup on heating elements can significantly reduce their efficiency, leading to increased energy consumption and longer heating times. By preventing limescale formation, the water treatment device may allow these heating elements to maintain their optimal performance, resulting in energy savings and improved user experience. The core may comprise any suitable number of ridges. The core may comprise three or more ridges. The core may comprise 4, 5, 6, 7, 8 or more ridges, for example. Where features are described in relation to a ridge, it should be understood that these features may equally apply to any further ridges present. The core may comprise a central portion of material extending along the longitudinal axis having a substantially constant cross-sectional shape. The central portion of material may be described as a main body. The main body may be defined as a portion of material extending along the longitudinal axis having a substantially circular cross section. At least one ridge may be formed integrally with the main body. The core may comprise a single unitary component. In this way, the central portion of material, or the main body, may be a descriptive term for a region of the core rather than a distinct component. At least one ridge may be formed separately from, and connected to, the main body. At least one ridge may extend along any suitable portion of the length of the core. Each ridge may extend along a substantial portion of the length of the core between the first end and the second end. Each ridge may comprise a similar length to at least one other ridge. Each ridge may comprise a similar, or the same, length to any other ridge. 06 03 24 At least one ridge may extend along a generally helical path. At least one ridge may form a helix about the main body of the core. Each ridge may generally form a helix about the main body of the core. 5 Each ridge may form a helix having a substantially constant angle relative to the longitudinal axis along the length of the ridge. A helix may be defined as a curve that makes a constant angle relative to a fixed line or axis, or a curve that makes a constant angle to a plane perpendicular to the longitudinal axis at any point 10 along the longitudinal axis. In some examples, the disclosed ridges may not have a constant angle relative to a fixed axis, instead at least one ridge may extend to form an angle to the longitudinal axis that varies along its length. Such arrangements may be described as a general helix shape having a non-constant or variable angle relative to a fixed axis or plane. Advantageously, at least one ridge having a variable angle may provide a non-constant flow path 15 through the conduit and therefore increases the induced turbulence. In this way, an increased proportion of mineral ions may precipitate to provide a colloidal dispersion. At least one ridge may comprise one or more regions angled substantially parallel to the longitudinal axis. Additionally or alternatively, at least one ridge may comprise one or more 20 regions angled substantially perpendicular to the longitudinal axis. At least one ridge may comprise one or more regions or sections angled substantially parallel to an imaginary plane, the imaginary plane being disposed perpendicular to the longitudinal axis of the core. At least one ridge may comprise one or more regions or sections angled substantially perpendicular to an imaginary plane, the imaginary plane being disposed perpendicular to the longitudinal axis of the core. At least one ridge may comprise one or more sections angled at approximately 0° relative to the longitudinal axis. At least one ridge may comprise one or more sections angled between 1° and 90° relative to the longitudinal axis. At least one ridge may comprise one or more sections angled at approximately 90° relative to the longitudinal axis. Each ridge may comprise a first side wall disposed on a first side of a peak, and a second side wall disposed on a second side of the peak. At least one ridge may comprise at least one side wall comprising a substantially planar surface, region or face. At least one ridge may comprise two opposing side walls where both side walls comprise at least one substantially planar surface, region or face. Each of the first side wall and second side wall may comprise one or more planar regions. The first side wall and second side wall may each comprise at least two adjacent planar regions where the two adjacent regions are angled relative to each other. In this way, the first side wall and second side wall may comprise at least two planar regions forming different angles relative to the longitudinal axis of the core. The first side wall and second side wall may each comprise a plurality of planar regions where adjacent regions are angled relative to each other. At least one ridge may comprise one or more regions where the two opposing side walls are disposed substantially parallel to each other. At least one ridge may comprise a peak having a substantially planar surface. At least one ridge may comprise a peak having a curved surface. In some examples, the peak may be described as a plateau. The distance between adjacent ridges may vary along the length of the core. The distance between adjacent ridges may be measured by the distance between two opposing points within an imaginary plane that is disposed perpendicularly to the longitudinal axis, where the two opposing points are the same distance from the longitudinal axis. The distance between adjacent ridges may be measured by the distance between a centre point of opposing peaks, each point being disposed within an imaginary plane that is disposed perpendicularly to the longitudinal axis. The distance between adjacent ridges may be measured by the closest distance between the adjacent ridges. The distance between adjacent ridges may be measured by the closest distance between the peaks of adjacent ridges. The distance between adjacent ridges may be measured not including any additional surface features such as grooves or protrusions. Advantageously, the distance between adjacent ridges varying along the length of the core may provide a non-constant sized flow path and therefore increase the induced turbulence. In this way, an increased proportion of mineral ions may precipitate to provide a colloidal dispersion. The thickness of at least one ridge may vary along its length. The thickness of at least one ridge may vary along its length at a plurality of regions. The thickness of at least one ridge may vary along its length at a plurality of regions. The cross-sectional shape defined by the main body and the ridges may be variable along the length of the core. Advantageously, at least one ridge having a variable thickness and / or variable cross-sectional shape may provide a non-constant flow path through the conduit and therefore increases the induced turbulence. In this way, an increased proportion of mineral ions may precipitate to provide a colloidal dispersion. The core may comprise one or more grooves disposed in the surface of the core. The core may comprise one or more grooves disposed in one or more side walls of one or more ridges. The one or more grooves may be angled relative to a flow of water passing therethrough. The one or more grooves may be angled substantially perpendicularly to a flow of water passing therethrough. The one or more grooves may be arranged substantially perpendicularly with the longitudinal axis of the core. The one or more grooves may be arranged at an angle to the longitudinal axis of the core. The one or more grooves may be arranged substantially parallel to a peak of a ridge. The one or more grooves may be arranged substantially perpendicular to a peak of a ridge. The one or more grooves may be disposed between adjacent ridges. The one or more grooves may comprise any suitable length. The core may comprise at least one groove disposed between each pair of adjacent ridges. The one or more grooves may extend in a helical curve along the longitudinal axis of the core. The one or more grooves may form an angle with the longitudinal axis of the core that varies along the length of the core. The core may comprise at least one groove angled relative to a flow of water passing therethrough and at least one groove arranged substantially parallel to a flow of water flowing therethrough. The core may comprise at least one groove disposed in a surface of at least one ridge. The core may comprise at least one groove disposed in a side wall of at least one ridge. Each groove may comprise any suitable dimensions. Each groove may comprise an elongate shape. Each groove may comprise a concave cross-sectional shape. Advantageously, one or more grooves may act to further increase the induced turbulence within the flow path. In this way, an increased proportion of mineral ions may precipitate to provide a colloidal dispersion. Advantageously, one or more grooves may increase the surface area of the core within the flow path. In this way, an increased proportion of mineral ions may precipitate to provide a colloidal dispersion. The core may comprise one or more protrusions disposed in the surface of the core. The core may comprise one or more protrusions disposed in one or more side walls of one or more ridges. Each protrusion may extend away from the longitudinal surface by a shorter distance than the ridges. The one or more protrusions may be angled relative to a flow of water passing therethrough. The one or more protrusions may be angled substantially perpendicularly to a flow of water passing therethrough. The one or more protrusions may be arranged substantially perpendicularly with the longitudinal axis of the core. The one or more protrusions may be arranged at an angle to the longitudinal axis of the core. The one or more protrusions may be arranged substantially parallel to a peak of a ridge. The one or more protrusions may be arranged substantially perpendicularly to a peak of a ridge. The one or more protrusions may be disposed between adjacent ridges. The one or more grooves may comprise any suitable length. The core may comprise at least one protrusion disposed between each pair of adjacent ridges. The one or more protrusions may extend in a helical curve along the longitudinal axis of the core. The one or more protrusions may form an angle with the longitudinal axis of the core that varies along the length of the core. The core may comprise at least one protrusion angled relative to a flow of water passing therethrough and at least one protrusion arranged substantially parallel to a flow of water flowing therethrough. The core may comprise at least one protrusion disposed in a surface of at least one ridge. The core may comprise at least one protrusion disposed in a side wall of at least one ridge. Each protrusion may comprise any suitable dimensions. Each protrusion may comprise an elongate shape. Each protrusion may comprise a convex cross / sectional shape. Advantageously, one or more protrusions may act to further increase the induced turbulence within the flow path. In this way, an increased proportion of mineral ions may precipitate to provide a colloidal dispersion. Advantageously, one or more protrusions may increase the surface area of the core within the flow path. In this way, an increased proportion of mineral ions may precipitate to provide a colloidal dispersion. In some examples, the core may comprise at least one groove and at least one protrusion. The core may comprise clamping regions disposed at each end. The clamping regions may each comprise two or more clamping ridges configured to extend further from the longitudinal axis than the ridges. The clamping ridges may extend parallel to the longitudinal axis. Advantageously, the clamping regions may provide a means for fixedly connecting the core within a conduit, for example, without requiring a direct connection with a ridge that doesn't form part of a clamping region. The core may comprise any suitable composition comprising at least copper, zinc, nickel, and tin. The core may comprise, by weight, 40%-50% copper. The core may comprise, by weight, 15%-25% nickel. The core may comprise, by weight, 20%-30% zinc. The core may comprise, by weight, 9%-15% tin. The core may comprise, by weight, approximately 45% copper, 20% nickel, 25% zinc and 10% tin. The core may comprise any suitable amount of titanium. The core may comprise any suitable amount of silver. The core may comprise any suitable amount of platinum. According to a second aspect, there is provided a non-sacrificial core for a water treatment device, the core extending along a length from a first end to a second end. The core may be configured to define at least one flow channel along the length of the core. The core may comprise a metallic or metal alloy material configured such that mineral ions within a flow of water, flowing over and / or near to the surface of the core, precipitate to provide a colloidal dispersion. At least one flow channel defined by the core may comprise at least one discontinuity, for example a flow direction discontinuity, along the length of the core. One or more of a dimension (for example, one or more of a width, a depth and a height) and a direction, for example a flow direction, of the at least one flow channel may vary along the length of the core. The core may comprise at least one wall structure defining or configured to define the at least one flow channel. The at least one wall structure may be configured such that one or more of a dimension (for example, width, depth, height) and a direction, for example a flow direction, of the at least one flow channel varies along the length of the core. The at least one wall structure may be arranged such that an angle of the wall structure, for example an angle along a longitudinal direction of the wall, varies along the length of the core relative to a longitudinal axis of the core. The at least one wall structure may comprise one or more regions angled substantially parallel to the longitudinal axis of the core. The at least one wall structure may comprise one or more regions angled substantially perpendicular to the longitudinal axis of the core. The at least one wall structure may comprise generally opposing side surfaces. The generally opposing side surfaces of the at least one wall structure may be angled relative to one another, for example may be non-parallel to one another. An angle between the generally opposing side surface may vary along a length of the at least one wall structure. The core may comprise a plurality of wall structures, for example, two, three, four, five etc. A distance between adjacent wall structures may vary along a length of the core. A thickness of the wall structure may vary along a length of the core. A cross-sectional shape of the core may vary along a length of the core. The core may comprise one or more grooves or apertures disposed in a surface of the core. The at least one wall structure may comprise the one or more grooves or apertures. The one or more grooves or apertures may be disposed between adjacent wall structures. The core may comprise one or more protrusions disposed on a surface of the core. The at least one wall structure may comprise the one or more protrusions. The one or more protrusions may be disposed between adjacent wall structures. The one or more protrusions may be angled relative to a flow direction of water along the at least one flow channel. The one or more protrusions may be angled substantially perpendicular to a flow direction of water along the at least one flow channel. The core may comprise a textured surface. The at least one wall structure may comprise a textured surface. The at least one wall structure may comprise a shot-peened surface. That may increase a surface area of the core. The non-sacrificial core of the second aspect may comprise one or more features of the non-sacrificial core of the first aspect, and vice versa. The non-sacrificial core of the second aspect may provide one, some or substantially all of the same advantages which may be provided by the non-sacrificial core of the first aspect. According to a third aspect, there is provided a water treatment device. The water treatment device may comprise a conduit extending between an inlet and an outlet. The conduit may be configured to convey a flow of water therethrough. The water treatment device may also comprise a non-sacrificial core disposed at least partially within the conduit. The non-sacrificial core may be the non-sacrificial core of the first aspect. According to a fourth aspect of the invention, there is provided a method of manufacturing a non-sacrificial core for a water treatment device, the core extending along a length from a first end to a second end. The core may comprise at least two ridges. Each ridge may extend away from a longitudinal axis of the core. Each ridge may extend along at least a portion of the length of the core. The core may comprise a metallic or metal alloy material configured such that mineral ions within a flow of water, flowing over and / or near to the surface of the core, precipitate to provide a colloidal dispersion. The core may be non-sacrificial core of the first aspect or of the second aspect. The method may comprise moulding the core, or forming the core by material extrusion or additive manufacturing such as powder bed fusion or directed energy deposition. The core may comprise, by weight, approximately 45% copper, 20% nickel, 25% zinc and 10% tin. The method of manufacturing the core may comprise applying a surface treatment to the core, such as shot-peening, for example to provide the core with a textured surface. Advantageously, applying a surface treatment, such as shot-peening, to provide the core with a textured surface may increase the surface area of the core. According to a fifth aspect of the invention, there is provided a method of manufacturing a water treatment device. The method may comprise forming a conduit extending between an inlet and an outlet. The conduit may be configured to convey a flow of water therethrough. The method may comprise disposing a non-sacrificial core at least partially within the conduit such that in use water flowing through the conduit will contact an outer surface of the core. The core may be or comprise the non-sacrificial core of the first aspect or of the second aspect. The core may comprise a clamping region, for example located at one or both ends of the core. The method may comprise applying a clamping force on to the conduit, for example to reduce an internal width or diameter of the conduit, to contact the clamping region such that core is securely or fixedly held within the conduit. The method may comprise applying the clamping force, for example at, adjacent or near the inlet and / or the outlet of the conduit. The term colloidal dispersion as used herein may refer to a mixture in which small particles of one substance are uniformly distributed throughout a second substance, such as mineral ions dispersed in water, forming a stable system with particle sizes typically in the range of 1 to 1000 nanometers. It will be understood that, except where mutually exclusive, any feature described herein with respect to any aspect of the invention may be applied to any other aspect of the invention. BRIEF DESCRIPTION OF THE DRAWINGS By way of the example only, the invention will now be described with respect to the following Figures in which: Figure 1 shows a water treatment device according to an embodiment of the present invention; Figure 2 shows a core of the water treatment device shown in Figure 1, comprising substantially helical ridges; Figure 3 shows a top or plan view of the core shown in Figure 2; Figure 4 shows another core for a water treatment device having ridges comprising discontinuities along a length of the core, according to an embodiment of the present invention; Figures 5 and 6 show the core shown in Figure 4 comprising clamping or support regions; Figure 7 shows a method for manufacturing a core for a water treatment device according to an embodiment of the present invention; and Figure 8 shows a method for manufacturing a water treatment device according to an embodiment of the present invention. Like reference numerals may indicate like elements. DETAILED DESCRIPTION Figure 1 shows a water treatment device 1 according to an embodiment of the present invention. The device 1 comprises a conduit 10 extending between an inlet 10a and an outlet 10b, the conduit 10 being configured to convey a flow of water therethrough. Additionally, the device 1 has a core 12 disposed within the conduit 10, configured to extend between the inlet 10a and the outlet 10b, such that in use water flowing through the conduit 10 will contact an outer surface of the core 12. The core 12 is shown in Figures 1, 2 and 3. The core 12 is made from a metallic or metal alloy material configured such that mineral ions within the water flowing over and / or near to the surface of the core 12 precipitate to provide a colloidal dispersion. The core 12 comprises a first ridge 12a, a second ridge 12b and a third ridge 12c extending in a helix along a longitudinal axis A of the core 12. Each ridge 12a, 12b, 12c extends along substantially along a full length or a majority of the length of the core 12, with each ridge 12a, 12b, 12c extending a substantially similar length along the core 12. Alternatively, the ridges 12a, 12b, 12c may extend different lengths, and one or more ridges 12a, 12b, 12c may extend along only a part of the length of the core 12. Each ridge 12a, 12b, 12c may alternatively be thought of as a wall structure, for example a wall structure extending radially away from a substantially central axis of the core 12 along a helical path. The central axis is substantially parallel to the longitudinal axis A. The ridges 12a, 12b, 12c or wall structures are configured to substantially define at least one flow channel along the length of the core 12, along which water can flow in use. In the embodiment shown, the ridges 12a, 12b, 12c are substantially equally distributed or spaced apart from one another around the longitudinal axis A as shown most clearly in Figure 3, although that is not essential. The core 12 may comprise a central portion of material extending along the longitudinal axis A from which the ridges 12a, 12b, 12c extend. The central portion of material may have any suitable shape, for example a substantially circular cross-section around which the ridges 12a, 12b, 12c wind following a helical path. In the embodiment shown, the ridges 12a, 12b, 12c are integral with the central portion. However, the ridges 12a, 12b, 12c may be formed separately from and attached to the central portion, for example using one or more fasteners, or complementary engagement features located on the central portion and the ridges 12a, 12b, 12c (for example, male and female engagement features such as a tongue and groove arrangement). The conduit 10 comprises a substantially consistent circular cross-sectional shape along its length between the inlet 10a and the outlet 10b. In other examples, the cross-sectional shape of the conduit 10 may be any suitable shape, for example oval, polygonal (for example, triangular, square, rectangular, pentagonal, hexagonal etc.) or may be an abstract shape. Additionally or alternatively, the cross-sectional shape of the conduit 10 may vary along its length. The conduit 10 is made from stainless steel, although any suitable material may alternatively be used, for example a metal or metal alloy or plastic material such as polyvinyl chloride (PVC). The core 12 is formed separately from the conduit 10, and is disposed within the conduit 10. The core 12 comprises a single unitary component. In other examples, one or more portions of the core 12 may be formed separately and connected (for example, permanently or releasably connected) by any suitable means, such as welding or any suitable mechanical means (for example fasteners such as screws, bolts or clamps) or chemical means. The core 12 comprises a clamping or support region 14 disposed at each end. Each clamping or support region 14 comprises a plurality of clamping protrusions or shoulders 14a that extend further from the longitudinal axis A (for example, substantially in a radial direction) than the ridges 12a, 12b, 12c. In this way, the clamping regions 14 may contact an inner surface of the conduit 10 without the ridges 12a, 12b, 12c contacting the inner surface of the conduit 10. In this way, the clamping regions 14 are configured to hold the core 12 in place inside the conduit 10 such that relative movement between the core 12 and conduit 10 can be substantially prevented. Alternatively, each clamping region 14 may comprise only a single clamping protrusion or shoulder 14a. It will also be appreciated the core 12 may comprise only a single clamping or support region 14 which may be provided at any suitable location on the core 12. Each ridge 12a, 12b, 12c extends away from the longitudinal axis A of the core towards an inside surface of the conduit 10. In the example shown, the ridges 12a, 12b, 12c do not contact the inside surface of the conduit 10. In other examples, at least one ridge 12a, 12b, 12c may contact the inner surface of the conduit 10. Figures 1, 2 and 3 illustrate a core 12 comprising ridges 12a, 12b, 12c arranged to form a substantially constant helix shape. Each ridge 12a, 12b, 12c extends along the length of the core 12 between the two opposing clamping regions 14. Each ridge 12a, 12b, 12c extends in a helical shape along the length of the core 12. Each ridge 12a, 12b, 12c forms a helix forming a consistent angle relative to the longitudinal axis A along the length of the ridge 12a, 12b, 12c. Each ridge 12a, 12b, 12c comprises a helix with a substantially identical pitch to the other ridges 12a, 12b, 12c. Alternatively, one or more of the ridges 12a, 12b, 12c may follow a substantially helical path comprising a variable angle relative to the longitudinal axis A along the length of the core 12, such that different parts of the helix formed by the one or more ridges 12a, 12b, 12c are arranged at different angles relative to the longitudinal axis A along the length of the core 12. The helix shape formed by such a ridge 12a, 12b, 12c may be substantially continuous and smooth, but the variable angle may cause a distance between adjacent ridges 12a, 12b, 12c (and thereby a flow channel defined between adjacent ridges 12a, 12b, 12c) to increase and / or decrease in width along the length of the core 12. Additionally or alternatively, a pitch of the helix of at least one ridge 12a, 12b, 12c may be different to a pitch of the helix of the other ridges 12a, 12b, 12c. That may also cause a distance between adjacent ridges 12a, 12b 12c (and thereby a flow channel defined between adjacent ridges 12a, 12b, 12c) to increase and / or decrease in width along the length of the core 12. Each ridge 12a, 12b, 12c comprise two spaced apart side walls disposed either side of a peak of the ridge 12a, 12b, 12c. In the embodiment shown, the side walls are spaced apart from another a substantially consistent distance along the length of the core 12, such that each ridge 12a, 12b, 12c has a substantially consistent thickness along the length of the core 12. Alternatively, a distance between the side walls of one or more ridges 12a, 12b, 12c may vary along a length of the core 12 (for example, increasing or decreasing a thickness of the ridge 12a, 12b, 12c) such that a distance between adjacent ridges 12a, 12b, 12c (and thereby a flow channel defined between adjacent ridges 12a, 12b, 12c) increases and / or decreases in width along the length of the core 12. In the embodiment shown, a plurality of apertures 16 are provided in the core 12. The apertures 16 are disposed between adjacent ridges 12a, 12b, 12c and are open structures configured to allow water to pass fully through from one opening of the aperture 16 to the other opening of the aperture 16. Alternatively, the apertures 16 may be provided in the ridges 12a, 12b, 12c, for example in the side walls of the ridges 12a, 12b, 12c. The apertures 16 each have a substantially oval or elongated shape, with a major axis of the oval or longitudinal axis of the elongated shape arranged at an angle relative to the longitudinal axis A. The major or longitudinal axis of the oval or elongated shape of the apertures is substantially perpendicular to a flow direction of water over the core 12, although that is not essential and the apertures 16 may be arranged at any suitable angle on the core 12, for example substantially parallel to a flow direction of water over the core. Alternatively, the apertures 16 may extend to substantially follow at least a part of the helical path of the ridges 12a, 12b, 12c. Additionally or alternatively, a plurality of grooves may be provided in the core 12. The grooves may be substantially similar to the apertures 16 but may not extend through a full thickness of each ridge 12a, 12b, 12c, instead only extending partially through a thickness of the ridges 12a, 12b, 12c to form a recess or cutaway in the surface of the core 12. The core 12 may additionally or alternatively comprise one or more protrusions extending from the surface of the core 12. The protrusions may be arranged as described above with respect to the apertures 16, albeit generally extending away from the surface of the core 12 (for example, away from a surface of the one or more ridges 12a, 12b, 12c) rather than into or through the surface of the core 12. The apertures 16, grooves and / or protrusions may provide the core 12 with a textured surface. The textured surface may be configured to provide topographical variation in a surface of the core 12, which may increase a surface area of the core and promote turbulence in a flow of water over the core 12. The textured surface of the core 12 may be provided by alternative structures, for example by a surface that has been machined or processed to provide topographical variation, such as via shot peening. Figure 4 shows another non-sacrificial core 112 for a water treatment device according to an embodiment of the present invention. The core 112 also comprises a first ridge 112a, a second ridge 112b and a third ridge 112c. Each ridge 11a, 112b, 112c may alternatively be thought of as a wall structure, for example a wall structure extending radially away from a substantially a substantially central axis of the core 112. The central axis of the core is substantially parallel to a longitudinal axis A of the core 11. The ridges 112a, 112b, 112c or wall structures are configured to define at least one flow channel along the length of the core 112, along which water can flow in use. In the embodiment shown, the ridges 112a, 112b, 112c are substantially equally distributed or spaced apart from one another around the longitudinal axis A, although that is not essential. The ridges 112a, 112b, 112c may share one or more structural similarities with the ridges 12a, 12b, 12c of the core 12 described with respect to Figures 1, 2 and 3. For example, a distance between side walls disposed either side of a peak of one or more ridges 112a, 112b, 112c may vary along a length of the core 112 may vary such that a thickness of the ridges 112a, 112b, 112c varies along a length of the core 112. A distance between the ridges 112a, 112b, 112c may vary along a length of the core 112. The core 112 or the ridges 112a, 112b, 112c may comprise one or more apertures, grooves or protrusions as described above. However, in contrast to the ridges 12a, 12b, 12c of the core 12, the ridges 112a, 112, 112c of the core 112 do not follow a smooth, continuous substantially helical path. Rather, the ridges 112a, 112b, 112c or wall structures of the core 112 comprise one or more discontinuities along the length of the core 112. The ridges 112a, 112b, 112c each follow a pseudo-helical path along the length of the core 112 in that the ridges 112a, 112b, 112c each wind around a central axis of the core 112, but the path followed by each of the ridges 112a, 112b, 112c comprises discontinuities each providing a distinct and sudden change of angle in the ridges 112a, 112b, 112c rather than a smooth, continuous path. The discontinuities in the ridges 112a, 112b, 112c provide discontinuities in the flow channels defined by the ridges 112a, 112b, 112c. Each ridge 112a, 112b, 112c comprises a first side wall disposed on a first side of a peak, and a second side wall disposed on a second side of the peak. Each of the first side wall and second side wall comprises a plurality of planar regions. The planar regions are connected to one another to form one or more discontinuities or changes in angle in each of the first and second side walls of the ridges 112a, 112b, 112c along the length of the core 112. The planar regions of thefirst side wall are angled relative to adjacent planar regions of the first side wall of each ridge 112a, 112b, 112c, and likewise for the second side wall of each ridge 112a, 112b, 112c. As shown in Figure 4, at some locations on the ridges 112a, 112b, 112c generally opposing planar regions of the first and second side walls of each ridge 112a, 112b, 112c are arranged substantially parallel to one another such that a thickness of the ridge 112a, 112b, 112c is substantially constant, whilst at other locations generally opposing planar regions of the first and second side walls of each ridge 112a, 112b, 112c are arranged at an angle relative to one another such that a thickness of the ridge 112a, 112b, 112c varies (for example, increase or decreases). The second side wall of each ridge 112a, 112b, 112c is arranged such that it does not form a mirror image of the first side wall of the ridge 112a, lib, 112c. That may result in the core 112 and / or the ridges 112a, 112b, 112c having a cross-sectional shape that varies along a length of the core 112. However, that is not essential, and the generally opposing planar regions of the first and second side walls may be arranged substantially parallel to one another along the length of the core 112 such that a thickness of the ridge 112a, 112b, 11c is substantially constant along the length of the core 112. Each pair of generally opposing planar regions of the first and second side walls of each ridge 112a, 112b, 112c forms a substantially distinct section or portion of the ridges 112a, 112b, 112c. As shown in Figure 4, some of the portions or sections of the ridges 112a, 112b, 112c are arranged substantially perpendicular to the longitudinal axis A of the core 112, some are arranged substantially parallel to the longitudinal axis A of the core 112, and some are arranged at a different angle relative to the longitudinal axis A of the core 112. It will be appreciated that in alternative arrangements one or more ridges 112a, 112b, 112c may comprise parallel and angled portions and no perpendicular portions, whilst in other arrangements one or more ridges 112a, 112b, 112c may comprise perpendicular portions and angled portions and no parallel portions. The portions or sections of the ridges 112a, 112b, 112c are arranged such that an angle of the ridges 112a, 112b, 112c varies along the length of the core 112, for example relative to the longitudinal axis A of the core 112. In the embodiment shown, the distance between adjacent ridges 112a, 112b, 112c (and thereby a width of a flow channel defined between adjacent ridges 112a, 112b, 112c) varies along the length of the core 112, although that is not essential and a distance between adjacent ridges 112a, 112b, 112c may be substantially consistent along the length of the core 112. It will be appreciated that in alternative embodiments, a core may comprise ridges combining structures from the ridges 12a, 12b, 12c and the ridges 112a, 112b, 112c. For example, a core may comprise one or more ridges following a substantially smooth, continuous helical path for a part of the length of the core, and following a path comprising one or more discontinuous or distinct changes in angle for another part of the length of the core. Figures 5 and 6 show a non-sacrificial core 212 for a water treatment device according to an embodiment of the present invention. The core 212 is substantially similar to the core 112 described with respect to Figure 4, with like reference numerals indicating like elements. The core 212 comprises clamping or support regions 214 substantially as described above with respect to the core 12 shown in Figures 1, 2 and 3. The clamping regions 214 each comprise a plurality of clamping protrusions or shoulders 214a that extend further from the longitudinal axis A (for example, substantially in a radial direction) than ridges 212a, 212b, 212c. Alternatively, each clamping or support region 214 may comprise only a single clamping protrusion or shoulder 214a. The core 212 may alternatively comprise a single clamping or support region 214 which may be provided at any suitable location on the core 212. The cores 12,112, 212 described with respect to Figures 1 to 6 comprise a metallic or metal alloy composition comprising, by weight, approximately 45% copper, 20% nickel, 25% zinc and 10% tin. Alternatively, the cores 12, 112, 212 may comprise any suitable composition comprising at least copper, zinc, nickel and tin. For example, the cores 12, 112, 212 may comprise, by weight, 40% to 50% copper, 15% to 25% nickel, 20% to 30% zinc and 9% to 15% tin. Such metallic or metal alloy compositions may provide a catalytic effect such that mineral ions within water flowing over the cores 12, 112, 212 precipitate to provide a colloidal dispersion. Figure 7 shows a method 400 of manufacturing a non-sacrificial core for a water treatment device according to an embodiment of the present invention. The method 400 may be used to manufacture the cores 12,112, 212 shown in Figures 1 to 6, and is described with respect to the core 12 shown in Figures 1 to 3. Step 402 of the method 400 comprises forming the core 12 comprising one or more ridges 12a or wall structures configured to substantially define at least one flow channel along the length of the core 12, along which water can flow in use. Step 402 comprises forming the core 12 from a metallic or metal alloy material configured such that mineral ions with a flow of water, flowing over a surface of the material, precipitate to provide a colloidal dispersion. In the embodiment shown, step 402 comprises forming the core 12 as a single component in which the one or more ridges 12a are integral to the core 12. Alternatively, the one or more ridges 12a may be formed separately from a central portion or main body of the core 12 and subsequently secured or fastened to the central portion of the core 12. For example, the one or more ridges 12a may be connected or fastened to the central portion of the core 12 via welding, mechanical fasteners, complementary engagement features or chemical means. In the embodiment shown, step 402 comprises forming the core 12, either as a single integral component or a plurality of separate connectable components, via material extrusion. Alternatively, step 402 may comprise forming the core 12 or components of the core 12 (for example, one or more ridges 12a or wall structures) using a moulding technique, or using an additive manufacturing technique such as powder bed fusion or directed energy deposition. Step 404 of the method 400 optionally comprises applying a surface treatment to the core 12, for example to provide the core with a textured surface. In the embodiment shown, step 404 comprises shot-peening the surface of the core 12. However, it will be appreciated any suitable surface treatment may be applied to the core 12, or no surface treatment may be applied to the core 12. Figure 8 shows a method 500 of manufacturing a water treatment device according to an embodiment of the present invention. The method 500 may be used to manufacture a water treatment device comprising one or more of the cores 12,112, 212 shown in Figures 1 to 6, and is described with respect to the water treatment device 1 described with respect to Figure 1. Step 502 of the method 500 comprises disposing the core 12 at least partially within a conduit 10, the conduit extending between an inlet 10a and an outlet 10b. In the embodiment shown, step 502 comprises disposing the core 12 at least partially within the conduit 10 such that in use water flowing through the conduit 10 will contact an outer surface of the core 12. Step 504 of the method 500 optionally comprises applying a clamping force to the conduit 10, for example to reduce an internal width or diameter of the conduit 10. That may bring the internal surface of the conduit 20 into contact with the clamping protrusions or shoulders 14a of the core 12, to secure or hold the core 12 in place inside the conduit 10. In the embodiment shown, step 504 comprises applying the clamping force at or adjacent the inlet 10a and outlet 10b of the conduit where the clamping regions 14 of the core 12 are located, although that is not essential. Alternatively, no clamping force may be applied and the inner surface of conduit may contact the shoulders 14a without a clamping force being applied, such that the core 12 is retained within the conduit 10 via a friction or interference fit. The core 12 may be secured within the conduit 10 using an alternative arrangement, for example using one or more end caps provided on the conduit 10. CXI CO From reading the present disclosure, other variations and modifications will be apparent to the skilled person. Such variations and modifications may involve equivalent and other features which are already known in the art of water treatment, and which may be used instead of, or in addition to, features already described herein. 20 06 25

Claims

1. A non-sacrificial core for a water treatment device, the core extending along a length from a first end to a second end, comprising:5 at least two ridges, each ridge extending away from a longitudinal axis of the core, andeach ridge extending along at least a portion of the length of the core;wherein at least one ridge comprises a plurality of ridge portions arranged end-to-end to form the ridge, wherein adjacent ridge portions are arranged at different angles relative to the longitudinal axis of the core to provide discontinuities in a flow direction along a flow 10 channel defined in part by the at least one ridge; andwherein the core comprises a metallic or metal alloy material configured such that mineral ions within a flow of water, flowing over the surface of the core, precipitate to provide a colloidal dispersion, wherein the metallic or metal alloy material comprises, by weight, 40%-50% copper, 15%-25% nickel, 20%-30% zinc and 9%-15% tin.

152. The core of claim 1, wherein at least one ridge comprises one or more regions angled substantially parallel to the longitudinal axis of the core.

3. The core of claim 1 or of claim 2, wherein at least one ridge comprises one or more 20 regions angled substantially perpendicular to the longitudinal axis of the core.

4. The core of any preceding claim, where at least one ridge comprises a first side wall disposed on a first side of a peak of the ridge, and a second side wall disposed on a second side of the peak of the ridge.

255. The core of claim 4, wherein the first side wall and the second side wall each comprise at least two adjacent planar regions which are angled relative to each other.

6. The core of any preceding claim, wherein a distance between adjacent ridges varies 30 along the length of the core.

7. The core of claim 6, wherein a distance between adjacent ridges is defined by a closestdistance between peaks of the adjacent ridges.20 06 258. The core of any preceding claim, wherein a thickness of at least one ridge varies along a length of the core.5 9. The core of any preceding claim, wherein a cross-sectional shape of the core varies alongthe length of the core.

10. The core of any preceding claim, further comprising one or more grooves disposed in a surface of the core.1011. The core of claim 10, wherein the one or more grooves are disposed in at least one ridge and / or between adjacent ridges.

12. The core of any preceding claim, further comprising one or more protrusions disposed 15 on a surface of the core.

13. The core of claim 12, wherein the one or more protrusions are disposed on at least one ridge and / or between adjacent ridges.20 14. The core of claim 13 or of claim 14, wherein the one or more protrusions are angledrelative to a flow direction of water flowing over the core, optionally wherein the one or more protrusions are angled substantially perpendicularly to a flow direction of water flowing over the core.25 15. The core of any preceding claim, further comprising at least one clamping region,comprising at least one clamping ridge configured to extend further away from the longitudinal axis of the core than the ridges.

16. The core of any preceding claim, wherein the metallic or metal alloy material comprises, 30 by weight, approximately 45% copper, 20% nickel, 25% zinc and 10% tin.

17. A water treatment device comprising:a conduit extending between an inlet and an outlet, configured to convey a flow of water therethrough; anda non-sacrificial core according to any preceding claim, disposed at least partially within the conduit.20 06 25

Images