GB2562724A

GB2562724A - A brine tank

Info

Publication number: GB2562724A
Application number: GB1708129.0A
Authority: GB
Inventors: Robert Sargeant William
Original assignee: Harvey Water Softeners Ltd
Current assignee: Harvey Water Softeners Ltd
Priority date: 2017-05-21
Filing date: 2017-05-21
Publication date: 2018-11-28
Anticipated expiration: 2037-05-21
Also published as: GB201708129D0; GB2562724B

Abstract

A brine tank 10 comprises a housing having one or more internal surfaces defining a space for accommodating a liquid and configured to receive a salt unit, the salt unit being adapted to release salt into said liquid to form a brine; wherein at least a portion of the one or more internal surfaces comprises a coating or layer (30, Fig. 2) adapted to reduce deposition of salt crystals on the portion of the one or more internal surfaces. The coating or layer can comprise Toyal Lotus (RTM). A water softener apparatus comprising the brine tank and a method of treating a brine tank are also claimed. The invention further relates to a coating material for use in a brine tank. The coating material, after being coated on at least a portion of one or more internal surfaces to form a coating layer, comprises a plurality of microscopic open cavities (32, Fig. 2) adapted to increase a contact angle for contacting brine on said coating layer thereby reducing deposition of salt crystals on said coating layer. A brine tank is also claimed, wherein one or more internal surfaces of the tank comprises a water repellent coating or layer.

Description

(71) Applicant(s):

Harvey Water Softeners Limited (Incorporated in the United Kingdom)

Hipley Street, Old Woking, Surrey, GU22 9LQ, United Kingdom (72) Inventor(s):

William Robert Sargeant (51) INT CL:

C02F 5/00 (2006.01) B08B 17/06 (2006.01)

C09D 5/16 (2006.01) (56) Documents Cited:

JP 2014015236 A US 20120211346 A1

US 20030096083 A1

JP H05293049 (58) Field of Search:

INT CL B08B, B65D, C02F, C09D

Other: WPI, EPODOC, PATENT FULLTEXT (74) Agent and/or Address for Service:

inCompass IP Europe Limited

Paddock Mead, Harlow, Essex, CM18 7RR, United Kingdom (54) Title of the Invention: A brine tank

Abstract Title: A brine tank with a coating to reduce deposition of salt crystals (57) A brine tank 10 comprises a housing having one or more internal surfaces defining a space for accommodating a liquid and configured to receive a salt unit, the salt unit being adapted to release salt into said liquid to form a brine; wherein at least a portion of the one or more internal surfaces comprises a coating or layer (30, Fig. 2) adapted to reduce deposition of salt crystals on the portion of the one or more internal surfaces. The coating or layer can comprise Toyal Lotus (RTM). A water softener apparatus comprising the brine tank and a method of treating a brine tank are also claimed. The invention further relates to a coating material for use in a brine tank. The coating material, after being coated on at least a portion of one or more internal surfaces to form a coating layer, comprises a plurality of microscopic open cavities (32, Fig. 2) adapted to increase a contact angle for contacting brine on said coating layer thereby reducing deposition of salt crystals on said coating layer. A brine tank is also claimed, wherein one or more internal surfaces of the tank comprises a water repellent coating or layer.

FIG. 1

1/3

FIG. 1

2/3

FIG. 2

3/3

FIG. 3

A Brine Tank

Field of the Invention

The invention relates to a brine tank for use in the field of liquid treatment. Particularly but not exclusively, the invention relates to a brine tank with an interior treated surface.

Background of the Invention

Water softening systems have been developed and widely used in domestic homes of countries in which water having high mineral content or so called “hard water” is supplied. In a typical water softening system such as an ion exchange water softener, the “hard ions” are generally removed by passing the “hard water” through a water softening cylinder in which an ion exchange medium is located. The medium exchanges the “hard ions” such as calcium or magnesium ions with “soft ions” such as sodium ions.

When all the available “soft ions” in the medium are depleted after a period of water softening, the medium can be regenerated by eluting the cylinder with a salt solution such as a brine. The brine is typically prepared and stored in a brine tank, in which salt in various forms such as pellets, granules, lumps or blocks are added from time to time so as to maintain the salinity of the brine at a desired level.

One common problem associated with the use of conventional brine tanks is the generation and, subsequently, the aggregation or accumulation of salt crystals on surfaces from the brine. More particularly, when the water of brine touching a surface in the brine tank evaporates over time, especially when the brine tank is located in a relatively hot and/or dry environment which accelerates the speed of evaporation, the increased concentration of salt in the brine on or near the surface will cause the formation of salt crystals on the surface, which, in water softening apparatuses for example, adhere and aggregate on surfaces of the internal walls of the brine tank. These aggregates of crystals will continue to grow over time, and will eventually become so bulky that they may substantially block the salt passageway in the tank, such that the pellets, granules or lumps of salt are prevented from descending into the water at the lower portion of the tank. The result is that the salinity of the brine decreases through reduced water contact with salt, and thus the normal functioning of the water softening system in supplying softened water to the users will be adversely affected.

The problem of salt crystal aggregation in a brink tank of a water softening apparatus is particularly disadvantageous for efficient operation for apparatuses of the type which utilize compressed salt blocks as the source of salt for forming the brine liquid. Normally, in such water softening apparatus, the compressed salt blocks are formed to have a cross-sectional size which closely matches the cross-sectional size of a salt block receiving chamber which communicates with the brine tank. In such systems, a lower end of the salt block is guided by the walls of the salt block chamber such that a lower end of the block extends into the water in the brine tank. Thus, the contact of the water with the lower portion of the salt block enables brine to be formed. As the lower portion of the salt block dissolves, the block falls under the influence of gravity thereby maintaining a lower portion of the remaining salt block in contact with the water. However, where salt crystals form around a brine liquid level in the lower part of the salt block chamber, such salt crystals may prevent the salt block moving down under the influence of gravity such that the salt block is no longer in contact with the water.

In general, salt crystallization in a brine tank can be overcome by manual removal of the salt aggregates, for example, by scraping off the salt crystals from the internal walls of the brine tank. To do this, however, the brine tank usually has to be removed from its point of installation and disconnected from the water softening system. Consequently, not only is this a laborious task which risks damage to the interior walls of the apparatus, but operation of the water softening system is interrupted during the cleaning process. In addition, in view of the fact that water softening systems are often installed out of sight in cupboards or the like, the disconnection of the brine tank for manual cleaning of the salt aggregates from the brine tank from time to time is tedious and inconvenient to the users, and thus there is a need to reduce or avoid the necessity to manually remove aggregated salt crystals from brine tanks.

Ob jects of the Invention

An object of the present invention is to provide a brine tank for use in liquid treatment, in which the aforesaid shortcomings are mitigated or at least to provide a useful alternative.

Another object of the invention is to mitigate or obviate to some degree one or more problems associated with known brine tank.

The above object is met by the combination of features of the main claims; the subclaims disclose further advantageous embodiments of the invention.

One skilled in the art will derive from the following description other objects of the invention. Therefore, the foregoing statements of object are not exhaustive and serve merely to illustrate some of the many objects of the present invention.

Summary of the Invention

In a first main aspect, the invention provides a brine tank comprising a housing having one or more internal surfaces defining a space for accommodating a liquid and configured to receive salt. The salt may be in the form of pellets, crystal or block salt or any other form of salt suitable for water softening systems or the like. The salt is adapted to slowly dissolve into said liquid to form a brine. At least a portion of the one or more internal surfaces of the brine tank comprises a coating or a layer adapted to reduce deposition of salt crystal on said portion of the one or more internal surfaces. The costing or layer is preferably water repellent.

In a second main aspect, the invention provides a coating material for use at a brine tank. The coating material, after being applied on at least a portion of one or more internal surfaces to form a coating or layer, preferably is water repellent and more preferably comprises a plurality of microscopic open cavities adapted to increase a contact angle for contacting a brine thereby reducing deposition of salt crystal on said coating or layer.

The summary of the invention does not necessarily disclose all the features essential for defining the invention; the invention may reside in a sub-combination of the disclosed features.

Brief Description of the Drawings

The foregoing and further features of the present invention will be apparent from the following description of preferred embodiments which are provided by way of example only in connection with the accompanying figures, of which:

Figure 1 is a cross sectional view showing an embodiment of a brine tank according to the present invention;

Figure 2 is a cross section view showing an embodiment of the coating or layer according to the present invention; and

Figure 3 is a plan view of an interior surface of a brine tank according to an embodiment of the present invention.

Description of Preferred Embodiments

The following description is of preferred embodiments by way of example only and without limitation to the combination of features necessary for carrying the invention into effect.

Reference in this specification to one embodiment or an embodiment means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. The appearances of the phrase in one embodiment in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Moreover, various features are described which may be exhibited by some embodiments and not by others. Similarly, various requirements are described which may be requirements for some embodiments but not other embodiments.

In the claims hereof, any element expressed as a means for performing a specified function is intended to encompass any way of performing that function. It is thus regarded that any means that can provide those functionalities are equivalent to those shown herein.

The present invention relates to a brine tank for use with a liquid treatment apparatus such as a water softening system. Particularly but not exclusively, the invention relates to a brine tank with a surface treated interior adapted to reduce, minimize or prevent deposition of salt crystals on interior surfaces. In general, a brine is prepared and stored in a brine tank, in which salt in its various forms, such as but not limited to, pellets, granules, lumps, crystals or compressed blocks, will be added from time to time so as to maintain the salinity of the brine. Particularly, a compressed block salt, or a so-called salt block, is preferred to be used in the brine tank as it allows an easy handling and loading of the salt in bulk form into the housing of the brine tank. The salt content in the salt block will then be slowly released into the water over time to generate the brine with the required salinity. More particularly, the salt in a lower portion of the salt block in contact with water in the brine tank will be slowly released in to the water for form brine for water softening.

Referring to Fig. 1, shown is an embodiment of the brine tank 10 according to the present invention. The brine tank 10 comprises a housing 12 having one or more internal surfaces 14 defining a space for accommodating a liquid and configured to receive one or more salt units 20. The salt units 20 can be any form of salt or salt containing substances or preparations, such as but not limited to, pellets, granules, lumps of salt, crystals, or devices which are adapted to carry and subsequently release salt, although salt units 20 in the form of salt blocks are illustrated in the drawings and described in the description as a preferred embodiment, without limitation to the scope of the invention.

In one embodiment, the housing 12 may comprise one or more partitions for dividing the housing space into one or more compartments 16 to receive and accommodate the corresponding one or more salt units 20, and optionally, other parts of the apparatus, such as one or more water softening cylinders 18, as shown in the drawing. The compartments 16 are in liquid communication with one another throughout the housing 12.

The salt units 20 are adapted to release salt into the liquid, which is typically water, supplied to a lower portion of the compartments 16 to form an aqueous solution of salt, i.e. brine. At least a portion of the one or more internal surfaces 14 has a coating or a layer 30 adapted to reduce deposition of salt crystals on said portion of the one or more internal surfaces 14. Preferably, the coating or layer 30 is arranged to span from above to below a normal brine level in the brine tank 10. More preferably, the coating or layer 30 is arranged to span a distance sufficient to cover a range of brine levels in the brine tank 10.

In general, the coating or layer 30 may comprise any possible compositions, structures and/or configurations capable of chemically and/or physically enhancing water repellence of the surface having the coating or layer 30. For example, the coating or layer 30 may comprise one or more functional agents which are water repellent. The water repellence may further be enhanced by, for example, providing one or more additional or intermediate layers, such as but not limited to, one or more layers of metallic material, such as aluminum; and/or one or more layers of polymeric material, such as polyethylene (PE), polytetrafluoroethylene (PTFE) and/or lacquer material in general, which may also serve to provide the functions of, for example, priming or improving mechanical protection to the coating or the coated surfaces, in addition to the water repelling effect.

In one preferred embodiment, the coating or layer 30 can be chemically engineered to comprise a plurality of microscopic open cavities 32, such as in the form of, for example, a plurality of open, small bubbles, as shown in Fig. 2. The microscopic open cavities 32 are shown in an exaggerated form in Fig. 2 for ease of illustration. In the context of this description, the term “microscopic” refers to the size of a substance or structure of a substance which is so small that it is not readily visible to the naked eyes, but may only be visible by using a microscope. The scale of sizes considered as being “microscopic” may therefore be, for example, micrometres, nanometres/submicron in scale, or below. In this embodiment, the plurality of microscopic open cavities 32 are adapted to increase a contact angle for the brine on said coating or layer 30 leading to an increased water repellence and thus a reduced deposition of salt crystals on said coating or layer 30. Preferably, the plurality of microscopic open cavities 32 are adapted to serve as microscopic pockets which entrap a minute amount of air therein to further enhance water repellence. More preferably, the microscopic open cavities 32 are arranged in a fractal structure, such as being arranged in a 3 dimensional fractal network.

The water repellence by the coating or layer 30 of the present invention can be considered analogous to the hydrophobicity observed on the leaf surfaces of lotus leaves. Particularly, the surfaces of lotus leaves have been found to be covered by numerous microscopic bumps. These bumps increase the contact angle at which water droplets such as rain contact the leaf surfaces, which then force the water droplets to form into microscopic water spheres. The water spheres are not small enough to fit in any gaps between the bumps, and therefore, are caused to roll off the leaf surfaces. This provides the mechanism for hydrophobicity of the lotus leaves. In one particular study of lotus leaves, it was disclosed that the contact angle between water and the leaf surface is typically about 150 degrees, with the water repellence increasing when the contact angle increases.

Inspired by this “lotus leaf effect”, the present invention applies a water repellent coating or layer to the internal surfaces of a brine tank or portions of said surfaces, and unexpectedly, the coating is found to offer a beneficial effect in reducing, minimizing or preventing aggregation of salt crystals on the coated or layered surfaces of the brine tank. The microscopic cavities 32 as provided by the embodiment of the present invention further create pockets of air to enhance the water-repelling effect. In one embodiment, the coating layer 30 of the present invention may comprise a commercially available coating material, TOYAL LOTUS®, manufactured by Toyo Aluminium K. K. The TOYAL LOTUS® material is found to offer a contact angle of about 170 degrees with water. TOYAL LOTUS® has been used as a packaging material in the food industry, such as in the lid of yoghurt containers to minimise adhesion of the yoghurt content to the lid. TOYAL LOTUS® has not been used in any applications relating to the field of liquid or water treatment, and particularly, has not been used in any applications relating to a brine tank. More particularly, the use of this or similar materials as a coating material for a brine tank in minimising, reducing or preventing salt crystallization has not been investigated or applied, and therefore, the beneficial effect is unexpected.

The present invention further relates to a coating material or layer for use in a liquid treatment apparatus such as a brine tank 10. The coating material or layer, after being coated on or adhered to at least a portion of one or more internal surfaces 14 to form a coating or layer 30, comprises a plurality of microscopic open cavities 32 adapted to increase a contact angle for contacting a brine on said coating or layer 30, thereby increasing water repellence of and thus reducing deposition of salt crystal on said coating or layer 30.

Preferably, the coating or layer 30 may comprise a plurality of microscopic open cavities 32 arranged in a fractal structure, such as a 3 dimensional fractal network. The open cavities 32 may serve as microscopic pockets to entrap a minute amount of air and thus form a plurality of air pockets to further enhance water-repellence of the coating or layer 30. The coating or layer 30 may comprise one or more water repelling, functional coatings or layers, which may comprise, for example, one or more of a metallic material and a polymeric material.

Fig. 3 provides a plan view of an interior surface 14 of a brine tank having a coating or layer 30 as hereinbefore described provided at least on a portion of the interior surface 14 covering a range of normal brine levels in a water softener apparatus. The dashed lines 40a, 40b respectively indicate upper and lower extents of the normal brine level in the water softener apparatus. However, it will be understood that the coating or layer 30 could be applied to the whole of the interior surface 14.

In one embodiment the layer 30 comprises a separately formed layer which is subsequently applied to selected portions of the interior surface 14. Such a layer 30 may be applied by adhering it to said portions of the interior surface 30. The separately formed layer may comprise an adhesive backed film material which carries the preferably water repellent material on the film surface. As such, the present invention also relates to a product comprising a self-adhering film carrying the anti-salt crystallisation material hereinbefore described on its front facing surface.

The present invention is advantageous in that it demonstrates high efficacy in reducing, minimizing and/or preventing growth of salt crystals in a brine tank. As above described, the beneficial effect attributes to the hydrophobicity or water-repellence as provided by the coating or layer at at least a portion of one or more internal surfaces of the brine tank, which significantly increases the contact angle between the coating or layer surface and the brine. As a consequence, the crystallization of salt on the coated or layered surface can be avoided or at least reduced or minimized.

The present description illustrates the principles of the present invention. It will thus be appreciated that those skilled in the art will be able to devise various arrangements that, although not explicitly described or shown herein, embody the principles of the invention and are included within its spirit and scope.

Moreover, all statements herein reciting principles, aspects, and embodiments of the invention, as well as specific examples thereof, are intended to encompass both structural and functional equivalents thereof. Additionally, it is intended that such equivalents include both currently known equivalents as well as equivalents developed in the future, i.e., any elements developed that perform the same function, regardless of structure.

While the invention has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only exemplary embodiments have been shown and described and do not limit the scope of the invention in any manner. It can be appreciated that any of the features described herein may be used with any embodiment. The illustrative embodiments are not exclusive of each other or of other embodiments not recited herein. Accordingly, the invention also provides embodiments that comprise combinations of one or more of the illustrative embodiments described above. Modifications and variations of the invention as herein set forth can be made without departing from the spirit and scope thereof, and, therefore, only such limitations should be imposed as are indicated by the appended claims.

In the claims which follow and in the preceding description of the invention, except where the context requires otherwise due to express language or necessary implication, the word “comprise” or variations such as “comprises” or “comprising” is used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention.

It is to be understood that, if any prior art publication is referred to herein, such reference does not constitute an admission that the publication forms a part of the common 5 general knowledge in the art.

Claims

1. A brine tank, comprising:

a housing having one or more internal surfaces defining a space for accommodating a liquid and configured to receive a salt unit, said salt unit being adapted to release salt into said liquid to form a brine;

wherein at least a portion of the one or more internal surfaces comprises a coating or layer adapted to reduce deposition of salt crystals on said portion of the one or more internal surfaces.

2. The brine tank according to claim 1, wherein the coating or layer comprises a plurality of microscopic open cavities adapted to increase a contact angle for the brine on a surface of said coating or layer to thereby reduce deposition of salt crystal.

3. The brine tank according to claim 2, wherein the plurality of microscopic open cavities are adapted to entrap a minute amount of air.

4. The brine tank according to claim 1, wherein the coating or layer comprises a fractal structure formed on said portion of the one or more internal surfaces.

5. The brine tank according to claim 4, wherein the fractal structure comprises a 3 dimensional fractal structure network formed on said portion of the one or more internal surfaces.

6. The brine tank according to claim 1, wherein the coating or layer comprises one or more functional layers which are water repellent.

7. The brine tank according to claim 1, wherein the coating or layer comprises one or more layers of metallic material.

8. The brine tank according to claim 1, wherein the coating or layer comprises one or more layers of polymeric material.

9. The brine tank according to claim 1, wherein the salt unit comprises a salt block.

10. The brine tank according to claim 1, wherein the coating or layer comprises a TOYAL LOTUS® coating or layer.

11. The brine tank according to claim 1, wherein the coating or layer of said portion of the one or more internal surfaces is arranged to span from above to below a brine level in the brine tank.

12. The brine tank according to claim 1, wherein the coating or layer of said portion of the one or more internal surfaces is arranged to span a distance sufficient to cover a range of brine levels in the brine tank.

13. A coating material for use in a brine tank, the coating material, after being coated on at least a portion of one or more internal surfaces to form a coating layer, comprises a plurality of microscopic open cavities adapted to increase a contact angle for contacting brine on said coating layer thereby reducing deposition of salt crystal on said coating layer.

14. The coating material according to claim 13, wherein the plurality of microscopic open cavities are arranged in a fractal structure.

15. The coating material according to claim 13, wherein the coating layer is adapted to entrap a minute amount of air.

16. The coating material according to claim 13, wherein the coating layer comprises one or more functional layers which are water repellent.

17. The coating material according to claim 13, wherein the coating layer comprises one or more of a metallic material and a polymeric material.

18. The coating material according to claim 13, comprising a TOYAL LOTUS® coating material.

19. A layer for use in a brine tank, the layer, after being applied on at least a portion of one or more internal surfaces, comprises a plurality of microscopic open cavities adapted to increase a contact angle for contacting brine on said layer thereby reducing deposition of salt crystal on said layer.

20. A brine tank for a water softener apparatus, comprising:

a housing having one or more internal surfaces defining a space for accommodating water and configured to receive salt, said salt releasing salt ions into said water to form brine;

wherein at least a portion of the one or more internal surfaces comprises a water repellent coating or layer.

21. A water softener apparatus having a brine tank according to any one of claims 1 to 20.

22. A method of treating a brine tank, comprising:

providing a housing having one or more internal surfaces defining a space for accommodating a liquid and configured to receive a salt unit, said salt unit being adapted to release salt into said liquid to form a brine; and applying to at least a portion of the one or more internal surfaces a coating or layer adapted to reduce deposition of salt crystals on said portion of the one or more internal surfaces.

Intellectual

Property Office

Application No: GB1708129.0