CARTRIDGE FOR TREATING DRINKING WATER, AND METHOD FOR ENRICHING DRINKING WATER WITH SILICON

Abstract

A cartridge and a method for enriching drinking water with silicon are provided. A cross-linked silicic acid is used, which can be mixed with a cation exchanger that is preferably loaded with hydrogen and/or with alkalizing agents and/or with activated carbon. Silicon can be released into the water via the silicic acid.

Claims

1.-18. (canceled)

19. A cartridge for treating water, comprising cross-linked silicic acid which, when water is passed therethrough, releases an amount of silicon such that for a dwell time of between 20 s and 20 min, an enrichment of the water with silicon of more than 5 mg/l, is achieved.

20. The cartridge as claimed in claim 19, wherein the cartridge contains activated carbon.

21. The cartridge as claimed in claim 19, wherein the cartridge contains a cation exchanger.

22. The cartridge as claimed in claim 19, wherein the cartridge contains an alkalizing filter material which comprises at least one of the materials selected from the group consisting of dolomites, half-burnt dolomites, calcium carbonate, magnesium carbonate, metal oxides, semimetal oxides, calcium oxide, magnesium oxide, magnesium hydroxide, alkali metal hydroxides, and alkaline earth metal hydroxides.

23. The cartridge as claimed in claim 19, wherein the cartridge is adapted for a pressure-driven or gravity-driven filter system.

24. The cartridge as claimed in claim 23, wherein the cross-linked silicic acid exhibits a loss on ignition at 1000° C. between 7% and 9%.

25. The cartridge as claimed in claim 19, wherein the cross-linked silicic acid exhibits a loss on drying between 55 and 65%.

26. The cartridge as claimed in claim 19, wherein the cross-linked silicic acid has a specific surface area between 820 and 1000 m.sup.2/g.

27. The cartridge as claimed in claim 19, wherein the cross-linked silicic acid exhibits a solubility at 25° C. of more than 80 mg/l.

28. The cartridge as claimed in claim 21, wherein the cross-linked silicic acid and/or the cation exchanger are in the form of granules with an average grain size from 0.5 to 3.0 mm.

29. The cartridge as claimed in claim 28, wherein the cation exchanger is loaded with at least hydrogen to at least 30% of its total capacity; and/or wherein it is filled with cross-linked silicic acid which has an SiO.sub.2 content, calculated on a basis of the dried substance, of at least 50%; or wherein the cross-linked silicic acid and the cation exchanger are provided in a volume ratio of 1:3 to 3:1; and/or wherein the cation exchanger is in the form of a weakly acidic cation exchange resin.

30. The cartridge as claimed in claim 21, wherein the cation exchanger is loaded with magnesium, sodium, lithium, zinc, and/or potassium to at least 5% of its total capacity; or wherein the cartridge is in the form of a disposable cartridge for a table water filter, an under-sink water filter, or for a machine for preparing beverages; or wherein the cartridges contain 20 ml to 10000 l of medium.

31. A table water filter, machine for preparing beverages, or under-sink water filter, comprising the cartridge according to claim 19.

32. A method for treating water, comprising: providing the cartridge as in claim 19; passing water to be treated through the cross-linked silicic acid and thereby enriching the water with silicon, wherein with a dwell time of between 20 s and 20 min, an enrichment with silicon of more than 5 mg/l is achieved.

33. The method as claimed in claim 32, wherein the water to be treated is enriched with 1 to 150 mg/l of silicon.

34. The method as claimed in claim 32, wherein the water to be treated is passed through a reverse osmosis system prior to being passed through the cross-linked silicic acid.

35. The method as claimed in claim 32, wherein the water to be treated is softened using a cation exchanger.

36. The method as claimed in claim 32, further comprising: filling a heating or cooling system with the treated water.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0084] The subject-matter of the disclosure will now be explained in more detail by way of schematically illustrated exemplary embodiments with reference to the drawings of FIGS. 1 through 5.

[0085] FIG. 1 is a perspective view of a table water filter.

[0086] FIG. 2 is a cut-away view of a cartridge containing an ion exchange material.

[0087] FIG. 3 shows a filter candle.

[0088] FIG. 4 schematically shows the cartridge installed in the tank of a beverage preparation machine.

[0089] FIG. 5 is a graph showing the Si enrichment of drinking water over the service life of a filter cartridge.

DETAILED DESCRIPTION

[0090] FIG. 1 shows a perspective view of a table water filter 1.

[0091] It is in the form of a gravity-driven water treatment device which is used in particular in the household.

[0092] Table water filter 1 comprises a filter cartridge 2 which is disposed in a funnel 3 which in turn is placed in the jug 4.

[0093] Drinking water can be filled into the funnel 3 via filling opening 6 and will then pass through the cartridge 2 and accumulate in the water collection space 5.

[0094] FIG. 2 shows a cut-away view of the cartridge 2 illustrated in FIG. 1.

[0095] Cartridge 2 comprises a housing 7 which has at least one chamber 9 that is filled with an ion exchange material and cross-linked silicic acid 8.

[0096] The filling material of the cartridge 2 is in particular in the form of granules, provided in the form of a mixed bed with a weakly acidic ion exchanger loaded with hydrogen ions and cross-linked silicic acid and optionally an alkalizing filter material.

[0097] Chamber 9 may also be filled with further water treatment media, in particular with activated carbon (not shown).

[0098] During operation, water runs into the chamber 9 via inlet openings 10, passes through the filling material 8 and leaves the cartridge 2 via outlet 11.

[0099] It goes without saying that filters or meshes for removing suspended matter and/or for retaining filling material 8 (not illustrated) can furthermore be provided upstream or downstream the filling material 8.

[0100] FIG. 3 shows an alternative embodiment of a device for treating water, which is in the form of a filter candle 12.

[0101] In contrast to the cartridge described above, such a filter candle 12 is flowed through not due to gravity, but rather is connected to a drinking water pipe via a suitable adapter.

[0102] For this purpose, the filter candle has a head 14 with a thread 13.

[0103] The head 14 comprises the inlet and the outlet. Filter cartridge 12 can be easily screwed in via the thread 13. The basic structure of such filter candles is known to those skilled in the art.

[0104] FIG. 4 schematically shows the tank 15 of a machine for preparing beverages, in particular a machine for preparing coffee.

[0105] Tank 15 has an intake port 16, through which water is supplied to the machine by a pump.

[0106] A filter cartridge 17 is plugged to the intake port 16, which filter cartridge is filled with an ion exchange material and cross-linked silicic acid 8. The ion exchange material is loaded with hydrogen, in accordance with the embodiments described above.

[0107] The enrichment of the drinking water with silicon will now be explained in more detail with reference to the graph of FIG. 5.

[0108] For this series of measurements, 120 ml of cross-linked silicic acid was filled into a cartridge. The filter bed was then rinsed with deionized water and used for a series of measurements for which silicon-free water with a total hardness of 26° dH and a carbonate hardness of 17° dH was used. The silicon content was determined in the eluate.

[0109] In the graph, the amount of filtered water is plotted on the x-axis, and the silicon content of the eluate is plotted on the y-axis.

[0110] It can be seen that silicon dissolves in a sufficient concentration and a plateau forms at 20 to 30 mg/l SiO.sub.2.

[0111] When admixed to a weakly acidic cation exchange material, the granules illustrated herein can be used to enrich the water with silicon and at the same time to soften it over the entire service life of the filter cartridge.

LIST OF REFERENCE NUMERALS

[0112] 1 Table water filter [0113] 2 Cartridge [0114] 3 Funnel [0115] 4 Jug [0116] 5 Water collection space [0117] 6 Filling opening [0118] 7 Housing [0119] 8 Filling material (mixture of ion exchange material and silicon dioxide) [0120] 9 Chamber [0121] 10 Inlet opening [0122] 11 Outlet [0123] 12 Filter candle [0124] 13 Thread [0125] 14 Head [0126] 15 Tank [0127] 16 Intake port [0128] 17 Filter cartridge