SINGLE-USE CAPSULE FOR WATER TREATMENT

Abstract

The invention relates to a single-use capsule (100) for water treatment. The single-use capsule comprises a capsule body (101) defining an inlet side (102) and an outlet side (103), a first cavity (104) located within the capsule body, and optionally, a flat sheet membrane filter (105) arranged within the capsule body. Furthermore, the first cavity comprises an ion exchange element.

Claims

1. A single-use capsule (100) for water treatment, the single-use capsule comprising: a capsule body (101) defining an inlet side (102) and an outlet side (103); and a first cavity (104) located within the capsule body; wherein the first cavity comprises an ion exchange element.

2. The single-use capsule according to claim 1, wherein the single-use capsule is configured for treating only less than 5 liters of water, preferably less than 4 liters of water, more preferably only less than 3 liters of water, and most preferably only less than 2 liters of water.

3. The single-use capsule according to claim 1, wherein the single-use capsule comprises a flat sheet membrane filter (105) arranged within the capsule body.

4. The single-use capsule according to claim 3, wherein the flat sheet membrane filter has a pore size of 0.2 m or lower, and preferably is an ultrafiltration flat sheet membrane filter.

5. The single-use capsule according to claim 3, wherein the flat sheet membrane filter has a thickness below 2 mm, preferably between 0.1 mm and 1 mm.

6. The single-use capsule according to claim 1, wherein the first cavity has a volume between 3 ml and 48 ml, preferably between 4 ml and 30 ml, and most preferably between 5 ml and 20 ml.

7. The single-use capsule according to claim 1, further comprising: a first filter layer (106) arranged between the first cavity and the inlet side; and/or a second filter layer (107) arranged between the first cavity and the outlet side.

8. The single-use capsule according to claim 7, wherein the first and/or second filter layer comprises a fibrous material; wherein the fibrous material of the first and/or second filter layer has a pore size between 0.5 m and 200 m, preferably between 10 and 150 m, and most preferably between 50 and 100 m, and/or wherein the fibrous material of the first and/or second filter layer has a specific weight between 10 g/m.sup.2 and 100 g/m.sup.2, preferably between 20 g/m.sup.2 and 80 g/m.sup.2, and most preferably between 30 g/m.sup.2 and 50 g/m.sup.2; and/or wherein the first and/or second filter layer has a thickness below 5 mm, preferably below 2 mm.

9. The single-use capsule according to claim 1, wherein the ion exchange element comprises a weak acid and/or strong acid cation exchange material, preferably a weak acid and/or strong acid cation exchange material, which is 100% in the hydrogen form, and most preferably a weak acid cation exchange material, which is 100% in the hydrogen form.

10. The single-use capsule according to claim 1, further comprising a flow limiting structure (111) for limiting the water flow through the single-use capsule below 150 l/h, preferably below 100 l/h, and most preferably below 40 l/h.

11. The single-use capsule according to claim 1, further comprising: an activated carbon element (108) located within the capsule body.

12. The single-use capsule according to claim 1, wherein the single-use capsule does not comprise silver, silver alloys or silver compounds.

13. The single-use capsule according to claim 1, wherein the capsule body is made of a material selected from the group consisting of plastic, bioplastic, oriented or non-oriented synthetic fibers, natural material, aluminum, and mixtures thereof.

14. The single-use capsule according to claim 1, wherein the capsule further comprises an acid composition comprising at least one acid and/or at least one acid salt within the first cavity and/or between the first cavity and the inlet side and/or between the first cavity and the outlet side, preferably the acid is selected from the group consisting of ascorbic acid, citric acid, fumaric acid, maleic acid, malic acid, tartaric acid, and mixtures thereof, and/or the acid salt is Cl.sup., SO.sub.4.sup.2, H.sub.2PO.sub.4.sup..

15. The single-use capsule according to claim 1, wherein the capsule body has a volume between 5 ml and 50 ml, preferably between 8 ml and 40 ml, and most preferably between 10 ml and 25 ml.

16. A receiving device (700) for receiving a single-use capsule according to any of the preceding claims, comprising: the single-use capsule (100) according to claim 1; wherein the receiving device is configured for guiding water through the single-use capsule for treating the water.

17. The receiving device according to claim 16, further comprising: a flow limiting device (705) configured for limiting the water flow through the single-use capsule below 150 l/h, preferably below 100 l/h, and more preferably below 40 l/h.

18. The receiving device according to claim 16, wherein the receiving device is configured for being attached to a water pipe (701), preferably to a water faucet such that water of the water pipe flows through the single use capsule in the receiving device.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0087] FIGS. 1A and 1B each show a single-use capsule according to an exemplary embodiment of the invention, respectively.

[0088] FIG. 2 shows a single-use capsule according to an exemplary embodiment of the invention.

[0089] FIGS. 3A and 3B each show a single-use capsule according to a further exemplary embodiment of the invention, respectively.

[0090] FIGS. 4A and 4B each show a single-use capsule according to a further exemplary embodiment of the invention, respectively.

[0091] FIGS. 5A and 5B each show a single-use capsule according to a further exemplary embodiment of the invention, respectively.

[0092] FIGS. 6A and 6B each show a receiving device according to a further exemplary embodiment of the invention, respectively.

[0093] FIG. 7 shows a beverage dispenser according to a further exemplary embodiment of the invention.

[0094] It shall be noted that the figures are not necessarily drawn to scale. Furthermore, if the same reference signs are used in different figures, they may refer to the same or to similar elements. The same or similar elements may however also be designated with different reference signs.

DETAILED DESCRIPTION OF THE FIGURES

[0095] FIGS. 1A and 1B each show a single-use capsule for treating water according to an exemplary embodiment of the invention. The single-use capsule 100 comprises a capsule body 101 defining an inlet side 102 and an outlet side 103. Furthermore, the single-use capsule 100 comprises a first cavity 104 which is located within the capsule body 101 and comprises an ion exchange element. The single-use capsule further comprises a flat sheet membrane filter 105. The flat sheet membrane filter 105 is configured for removing bacteria from water flowing through the capsule body 101. In FIG. 1A it is shown that the flat sheet membrane filter is arranged between the first cavity 104 and the inlet side 102 and in FIG. 1B it is shown that the flat sheet membrane filter 105 is arranged between the first cavity 104 and the outlet side 103.

[0096] In other words, the single-use capsule 100 has a layered structure within the capsule body 101 wherein according to the exemplary embodiment of FIG. 1A the upper layer is composed by the flat sheet membrane filter 105 and the lower layer comprises first cavity 104 with the ion exchange element, whereas according to the exemplary embodiment of FIG. 1B the upper layer comprises the first cavity 104 and the lower layer comprises the flat sheet membrane filter 105. These layers may be vertically arranged with regard to the overall water flow from the inlet side 102 to the outlet side 103. In the exemplary embodiments of FIGS. 1A, 1B, 2, 3A, 3B, 4A, and 4B, it is shown that the capsule body 101 has the shape of a truncated cone, wherein the inlet side 102 is defined by the bottom surface of the truncated cone and the outlet side 103 is defined by the top surface of the truncated cone. Although, these exemplary embodiments shows a capsule body in the shape of a truncated cone, also other shapes are possible, for example any rotational symmetric body such as a cylinder, a truncated cone, a truncated pyramid, etc. Thus, the bottom and top surfaces of the capsule body 101 may also have a non-circular shape such as an oval shape, a quadratic or polygonal shape. The capsule body 101 may be made of a material that is selected from the group consisting of plastic, bioplastic, oriented or non-oriented synthetic fibers, natural material such as cellulose, and mixtures thereof. The volume of the capsule body 101 may be between 5 ml and 50 ml, preferably between 8 ml and 40 ml, most preferably between 10 ml and 25 ml. The single-use capsule 100 may be configured for treating only less than 5 liters of water, preferably only less 4 liters of water, more preferably only less than 3 liters of water, and most preferably only less than 2 liters of water. Furthermore, the single-use capsule 100 may not comprise any silver, silver alloys or silver compounds such that no silver is released to the water. The inlet side 102 and/or the outlet side 103 of the capsule body 101 may define openings that are smaller than 500 m, preferably smaller than 200 m such that it is not necessary to provide additional filter layers as shown in the exemplary embodiment of FIG. 2.

[0097] The first cavity may have a volume between 3 ml and 48 ml, preferably between 4 ml and 30 ml, and most preferably between 5 ml and 20 ml. The flat sheet membrane filter 105 may be an ultrafiltration membrane and may have a pore size of 0.2 m or less. Furthermore, the flat sheet membrane filter 105 may have a thickness below 2 mm, preferably between 0.1 mm and 1 mm. The flat sheet membrane filter 105 acts as a bacteria barrier in the single-use capsule 100. The ion exchange material may comprise a weak acid and/or strong acid cation exchange material.

[0098] FIG. 2 shows a single-use capsule 100 according to a further exemplary embodiment of the invention. In addition to the single-use capsule shown in FIGS. 1A and 1B, the single-use capsule 100 comprises first and second filter layers 106 and 107. The first filter layer 106 is arranged between the inlet side 102 and the first cavity 104 and the second filter layer 107 is arranged between the outlet side 103 and the first cavity. According to this exemplary embodiment, the flat sheet membrane filter is arranged between the first cavity 104 and the second filter layer 107. However, the flat sheet membrane filter may also be arranged at other positions such as between the first filter layer 106 and the first cavity 104, between the inlet side 102 and the first filter layer 106, and/or between the second filter layer 107 and the outlet side 103. The first and/or the second filter layer may comprise a fibrous material. The fibrous material may have a pore size between 0.5 m and 200 m, preferably between 10 m and 150 m, and most preferably between 50 m and 100 m. Alternatively or additionally, the fibrous material of the first and/or second filter layer may have a specific weight between 10 g/m.sup.2 and 100 g/m.sup.2, preferably between 20 g/m.sup.2 and 80 g/m.sup.2, and most preferably between 30 g/m.sup.2 and 50 g/m.sup.2. Additionally or alternatively the first and/or second filter layer may have a thickness below 5 mm, preferably below 2 mm.

[0099] FIGS. 3A and 3B show single-use capsules 100 according to further exemplary embodiments of the invention. The single-use capsules 100 comprise a first cavity 104 with an ion exchange element, a flat sheet membrane filter 105, first and second filter layers 106 and 107, as well as an activated carbon element 108. According to the exemplary embodiment of FIG. 3A, the activated carbon element 108 is arranged between the first filter layer 106 and the first cavity 104. The flat sheet membrane filter 105 is arranged between the first cavity 104 and the second filter layer 107. Viewed from the inlet side 102 to the outlet side 103, the activated carbon element 108 is arranged after the first filter layer 106, the first cavity 104 is arranged after the activated carbon element 108, the flat sheet membrane filter 105 is arranged after the first cavity 104 and the second filter layer 107 is arranged after the flat sheet membrane filter 105. According to the exemplary embodiment of FIG. 3B, the flat sheet membrane filter 105 is arranged between the first cavity 104 and the second filter layer 107 and the activated carbon element 108 is arranged between the first cavity 104 and the flat sheet membrane filter. Viewed from the inlet side 102 to the outlet side 103, the first cavity 104 is arranged after the first filter layer 106, the activated carbon element 108 is arranged after the first cavity 104, the flat sheet membrane filter 105 is arranged after the activated carbon element 108 and the second filter layer 107 is arranged after the flat sheet membrane filter 105. However, also other arrangements of the different layers 104, 105, 106, 107, and 108 are possible. Furthermore, the single-use capsule 100 may also be provided without the first and second filter layers 106 and 107 or with only one of the first and second filter layers 106 and 107. For example, the inlet side 102 and/or the outlet side 103 may comprise openings that are smaller than 500 m, preferably smaller than 200 m, as described in the context of FIGS. 1A and 1B instead of having filter layers.

[0100] In FIGS. 4A and 4B single-use capsules 100 according to further exemplary embodiments of the invention are shown. The single-use capsules 100 shown in FIGS. 4A and 4B comprise a first cavity 104, a flat sheet membrane filter 105 and an acid composition 109, respectively. According to these exemplary embodiments, the acid salt composition 109 is arranged as a layer in the capsule body 101. However, the acid composition 109 may also be located within the first cavity 104 and/or be mixed with the ion exchange element. The acid composition may as an alternative be situated before the first cavity 104 containing the ion exchanger. The acid composition may comprise ascorbic acid, citric acid, fumaric acid, maleic acid, malic acid, tartaric acid, and mixtures thereof. The capsule may further comprise a fleece 110 in order to retain solid acid composition particles within the capsule. The single-use capsule shown in FIG. 4B shows an embodiment, wherein the acid composition layer 109 is arranged between the flat sheet membrane filter 105 and the first cavity 104. In the exemplary embodiments shown in FIGS. 4A and 4B, the acid composition 109 is provided in a solid form. However, the acid composition may also be provided in a liquid form and, e.g., be arranged within a punctuable bag.

[0101] FIGS. 5A and 5B each show a single-use capsule 100 according to a further exemplary embodiment, which single-use capsule 100 additionally comprises a flow limiting structure 111 that is configured for limiting the water flow through the single-use capsule below 150 l/h, preferably below 100 l/h, most preferably below 40 l/h. The flow limiting structure 111 may be a throttle. In FIG. 5A, it is shown that the flow limiting structure 111 is arranged at the inlet side 102 and in FIG. 5B it is shown that the flow limiting structure 111 is arranged at the outlet side 103.

[0102] In FIGS. 6A and 6B, a receiving device 700 according to an exemplary embodiment is shown, respectively. The receiving device 700 is configured for receiving the single-use capsule 100 and for guiding water through the single-use capsule 100 for treating the water. In FIG. 6A it is shown that the receiving device 700 is installed at the end of a water faucet 701. The receiving device further comprises a flow limiting device 705. In FIG. 6B, it is shown that the receiving device 700 is provided in beverage dispensing device 702, e.g. a coffee machine. The beverage dispensing device 702 may be configured for guiding water 703 through the receiving device 700 such that treated water 704 is provided for preparing the beverage.

[0103] FIG. 7 shows a beverage dispenser 710 according to a further exemplary embodiment of the invention. The beverage dispensing device 710 comprises a first receiving device 700 configured for receiving a single-use capsule 100 for treating water. Furthermore, the beverage dispensing device comprises a second receiving device 711 configured for receiving a second capsule 712. The second capsule for example comprises a beverage base such as coffee, tea, lemonade, etc. The first and second receiving devices 700, 711 are arranged such that water 713 first flows through the first receiving device 700 and the first capsule 100 and subsequently through the second receiving device 711 and the second capsule 712. The first capsule 700 treats the incoming water 713 such that treated water (e.g. purified, decarbonized and/or softened) 714 is provided. The second capsule 712 adds the beverage base to the treated water 714 such that a beverage 715 is provided by the beverage dispensing device 710.

[0104] While the invention has been illustrated and described in detail in the drawings and the foregoing description, such drawings and description are to be considered illustrative or exemplary and not restrictive. Thus, the invention is not limited to the disclosed embodiments. Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention from a study of the drawings, the disclosure, and the appended claims.

[0105] In the claims, the word comprising does not exclude other elements or steps, and the indefinite article a or an does not exclude a plurality. The mere fact that the certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. Any reference signs in the claims should not be construed as limiting the scope.

Examples

1. Measurement Methods

[0106] In the following, measurement methods implemented in the examples are described.

Water Hardness

[0107] The carbonate hardness (alkalinity) and total hardness of the feed water and the carbonate hardness of the treated water was determined at room temperature using a Tetra GH/TH Testkit (Tetra GmbH, Germany).

[0108] The pH value of the feed water and the treated water was determined at room temperature using the Greisinger pH Meter GPH 114 and the electrode GE 114 (GHM Messtechnik GmbH, Germany).

Conductivity

[0109] The conductivity of the feed water and the treated water was determined at room temperature using the Geisinger conductivity meter GLF 100 (GHM Messtechnik GmbH, Germany).

2. Materials

Capsule 1

[0110] Cylindric capsule dimensions: inner diameter: 25 mm; outer diameter: 30 mm; height: 30 mm.

[0111] Ion exchange element material: weak acid cation exchanger in H.sup.+ form based on crosslinked polyacrylate (Lewatit S8227, LanXess AG, Germany).

Ion exchange element volume: 10 ml.
Capsule body material: Polyethylene (PE).

[0112] In the inlet and outlet of the capsule a PE fleece (Viledon, Freudenberg AG, Germany) was installed, and an ultrafiltration membrane (Sartorius cellulose acetate membrane type 111, diameter 25 mm, pore size 0.2 m, Sartorius AG, Germany) was installed between the inlet fleece and the ion exchange element.

Capsule 2

[0113] Cylindric capsule dimensions: inner diameter: 20 mm; outer diameter: 25 mm; height: 50 mm.

[0114] Ion exchange element material: weak acid cation exchanger in H.sup.+ form based on crosslinked polyacrylate (Lewatit S8227, LanXess AG, Germany).

Ion exchange element volume: 15 ml.
Capsule body material: Polyethylene (PE).

[0115] In the inlet and outlet of the capsule a PE fleece (Viledon, Freudenberg AG, Germany) was installed, and an ultrafiltration membrane (Sartorius cellulose acetate membrane type 111, diameter 20 mm, pore size 0.2 m, Sartorius AG, Germany) was installed between the inlet fleece and the ion exchange element.

Capsule 3

[0116] Cylindric capsule dimensions: inner diameter: 20 mm; outer diameter: 25 mm;
height: 50 mm.

[0117] Ion exchange element material: weak acid cation exchanger in H.sup.+ form based on crosslinked polyacrylate (Lewatit S8227, LanXess AG, Germany).

Ion exchange element volume: 15 ml.
Capsule body material: Polyethylene (PE).

[0118] In the inlet and outlet of the capsule a PE fleece (Viledon, Freudenberg AG, Germany) was installed, and an ultrafiltration membrane (Sartorius cellulose acetate membrane type 111, diameter 20 mm, pore size 0.2 m, Sartorius AG, Germany) was installed between the inlet fleece and the ion exchange element. Furthermore, a layer containing 0.5 g ascorbic acid was installed between the ion exchange element and the fleece at the outlet of the capsule.

Feed Water 1

Conductivity:

[0119] pH: 7.5
Carbonate hardness: 11 dKH, 1.96 mmol/l.
Total hardness: 13 dH; 2.32 mmol/l.

Feed Water 2

Conductivity: 644 S/cm

[0120] pH: 7.5
Total hardness: 17 dH; 3.03 mmol/l.

3. Examples

Example 1

[0121] A receiving device in form of a cylindrical adapter was attached to the inner thread of a water faucet (in place of the aerator) and equipped with capsule 1. The capsule walls were sealed within the adapter using a flat seal ring so that the total amount of inflowing water flowed through the capsule. A total water volume of 21 feed water 1 was passed through the capsule in 50 ml portions with a water volume flow rate of 0.4-0.5 l/min (24-30 l/h). After every 50 ml water portion, the carbonate hardness (alkalinity), the pH, and the conductivity of the treated water volume were measured. The results are compiled in Table 1 below.

TABLE-US-00001 TABLE 1 Carbonate hardness, pH, and conductivity of water that has been passed through capsule 1. Treated water volume Carbonate hardness Conductivity Sample [ml] [dKH] pH [S/cm] 1-1 50 5 6.5 238 1-2 50 5 6.5 240 1-3 50 6 6.6 257 1-4 50 6 6.6 262 1-5 50 6 6.6 274 1-6 50 6 6.6 271 1-7 50 6 6.6 272 1-8 50 6 6.6 273 1-9 50 6 6.6 278 1-10 50 6 6.6 280 1-11 50 6 6.6 283 1-12 50 6 6.7 285 1-13 50 6 6.7 284 1-14 50 6 6.7 282 1-15 50 6 6.7 283 1-16 50 6 6.7 280 1-17 50 6 6.7 281 1-18 50 6 6.7 285 1-19 50 6 6.7 289 1-20 50 6 6.7 291 1-21 50 6 6.8 293 1-22 50 6 6.8 297 1-23 50 6 6.8 298 1-24 50 6 6.8 298 1-25 50 6 6.8 296 1-26 50 6 6.8 295 1-27 50 6 6.8 291 1-28 50 7 6.8 295 1-29 50 7 6.8 294 1-30 50 7 6.8 297 1-31 50 7 6.8 296 1-32 50 7 6.8 298 1-33 50 7 6.8 300 1-34 50 7 6.8 295 1-35 50 7 6.8 298 1-36 50 7 6.9 301 1-37 50 7 6.9 304 1-38 50 7 6.9 300 1-39 50 7 6.9 301 1-40 50 7 7.0 302

[0122] As shown in Table 1 above, the pH value of the treated water was 6.5 at the beginning and shifted to 7.0 after 21 of the total feed water volume have been passed through the capsule. This test procedure was repeated 20 times (40 l of treated water). Each liter was heated up to 100 C. in a kettle. In parallel also 40 l of feed water 1 were boiled in a second kettle. Subsequently, the lime precipitation was determined in both kettles by dissolving the lime precipitation with 1 liter diluted chloric acid and detecting by calcium and magnesium concentration by ICP (Coupled Argon Plasma) analysis. It was found that about 90% less lime has been precipitated in the kettle fed with the treated water. Thus, the inventive capsule can provide efficient lime scale protection.

Example 2

[0123] A receiving device in form of a cylindrical adapter was attached to the inner thread of a water faucet (in place of the aerator) and equipped with capsule 2. The capsule walls were sealed within the adapter using a flat seal ring so that the total amount of inflowing water flowed through the capsule. A total water volume of 21 feed water 1 was passed through the capsule in 1000 ml portions with a water volume flow rate of 0.3 l/min (18 l/h). pH, conductivity and carbonate hardness were measured in the first and the second liter of treated water.

TABLE-US-00002 TABLE 2 Carbonate hardness, pH, and conductivity of water that has been passed through capsule 2. Treated water volume Carbonate hardness Conductivity Sample [ml] [dKH] pH [S/cm] 2-1 1000 6 6.6 280 2-2 1000 7 6.8 295

[0124] As shown in Table 2 above, the pH value of the treated water was 6.6 at the beginning and shifted to 6.8 after 21 of the total feed water volume have been passed through the capsule.

Example 3

[0125] A receiving device in form of a cylindrical adapter was attached to the inner thread of a water faucet (in place of the aerator) and equipped with capsule 3. The capsule walls were sealed within the adapter using a flat seal ring so that the total amount of inflowing water flowed through the capsule. A total water volume of 5 l feed water 2 was passed through the capsule in 1000 ml portions with a water volume flow rate of 0.3 l/min (18 l/h). After every 1000 ml water portion, the pH, and the conductivity of the treated water volume were measured. The results are compiled in Table 3 below.

TABLE-US-00003 TABLE 3 Carbonate hardness, pH, and conductivity of water that has been passed through capsule 3. Treated water volume Conductivity Sample [ml] pH [S/cm] 3-1 1000 5.9 500 3-2 1000 6.6 510 3-3 1000 6.6 530 3-4 1000 6.7 540 3-5 1000 6.8 560

[0126] As shown in Table 3 above, the pH value of the treated water was 5.9 at the beginning and shifted to 6.8 after 5 l of the total feed water volume have been passed through the capsule. Thus, by arranging a layer comprising an acid within the capsule, the lime scale protection efficacy can be further improved and the inventive capsule can also provide efficient lime scale protection for larger water volumes.