EP3983344A1

EP3983344A1 - Method and domestic appliance for producing mineral water from tap water

Info

Publication number: EP3983344A1
Application number: EP20731106.9A
Authority: EP
Inventors: Philippe TOB
Original assignee: Aqvita Srl
Current assignee: Aqvita Srl
Priority date: 2019-06-17
Filing date: 2020-06-10
Publication date: 2022-04-20
Also published as: WO2020254173A1; BE1027370A1; BE1027370B1

Abstract

The invention concerns a method for producing mineral water, which involves mineralising a volume of water by passing it through a removable pod containing a determined quantity of mineral elements and enzymes which catalyse the reaction of carbon dioxide and water to form bicarbonate, so as to improve the dissolution of the mineral elements contained in the pod. The invention also concerns the appliance for implementing the method and the complementary pod.

Description

Method and domestic apparatus for producing mineral water from tap water.

The invention relates to the field of domestic production of mineral water, still or sparkling.

In particular, each home, and more generally each building dedicated to welcoming people, whether in a private or professional setting, is connected to a water distribution network for its supply of running water, also called drinking water. city, mains water or tap water. Generally, in many countries, this tap water is drinkable, that is to say suitable for consumption without risk to health.

It is however frequent that the taste properties of this water are not excellent. An unpleasant taste of chlorine, resulting from disinfection treatments, often persists in the water. This taste is annoying not only when the water is directly consumed, but also persists in preparations using this water, such as, for example, in tea or coffee.

To overcome this problem, households buy bottles of spring water or natural mineral water, having a taste, a flavor, which they like. It is indeed well known that each mineral water has unique taste properties, which depend on the ratios of the different mineral elements it contains. However, the recommended consumption being one and a half liters of water per day per person, the volume to be moved from the store to the home can be a real burden.

To avoid purchasing large volumes of water, many households instead use filter jugs to improve the taste of tap water. This type of carafe is designed so that a volume of water taken from the tap is entrained, under the effect of gravity, through a filter cartridge, usually containing activated carbon. The water thus filtered is generally free of its bad taste, but also of most of its minerals. The filter cartridge has a limited life and must be replaced very regularly, usually every month. The taste quality and The mineral water filtered in this type of carafe is not constant over the life of the cartridge, depending on whether the cartridge is new or at the end of its life. In addition, the water thus filtered is not instantly available. Due to the configuration of the carafe, it is necessary to wait until the entire volume of water withdrawn has been filtered before being able to pour it into a glass, otherwise the unfiltered water will leak.

More sophisticated systems are also available, generally for use in businesses. Most of the known systems include a reservoir in which the purified water is stored until use. The possibility of bacteria and / or algae or solid mineral particles developing in the tanks during storage can be compensated for by a recirculation system through a filter in order to be able to obtain water of determined quality at any time. The presence of reservoirs, however, makes this system bulky and energy intensive because of the recirculation of the mineral water produced between the reservoirs. In addition, the mineral elements used here are mainly chlorides and sulphates, for their ease of dissolution, which is not desirable from a taste point of view. The use of chlorides and sulphates is done to the detriment of carbonates, which are naturally present in commercial mineral waters and would be preferable from a taste and digestive point of view.

Application PCT / EP2018 / 057868 describes for its part a domestic system for producing water in line, that is to say not involving a water storage tank, production being carried out on demand. This system provides for circulating city water in a circuit passing in series through a filtration unit, a demineralization unit and a re-mineralization unit. The remineralization unit here comprises at least one secondary inlet, connected to a fluidic microdosing device for the injection of a predetermined volume of mineral powders or of a solution concentrated in minerals. Provision can be made to provide the concentrated solution and / or the powders in the form of “consumable” bottles or refills, that is to say that attach themselves directly to the fluidic microdosing valves and can be discarded when they are empty.

In order to offer more flexibility to the user, the applicant has found it necessary to improve the remineralization process by developing its flexibility. Solution of the invention

To this end, the present invention provides a process for producing a predefined volume of mineral water, a process comprising the following steps:

- a predefined volume of water is mineralized by passing it through a removable pod containing a determined quantity of mineral elements, so as to dissolve the mineral elements contained in the pod,

process characterized by the fact that

- carbon dioxide is introduced before or during mineralization and

- Enzymes catalyzing the reaction of carbon dioxide and water are used to convert at least part of the carbon dioxide introduced into bicarbonate.

It is possible that the water that is mineralized is city water, that is to say tap water.

In some cases, this water has an inappropriate mineral content. It may then be necessary to demineralize, at least in part, the predefined volume of water to obtain a predefined volume of demineralized water, before the latter is mineralized.

The terms mineralization and remineralization are used interchangeably to refer generally to the addition of minerals.

The determined quantity of minerals can correspond to the difference between the determined content of mineral elements, that is to say that one wishes to obtain in the predefined volume of mineral water, and the content of the introduced water, demineralized. or not, for the preset volume. The minerals are preferably completely dissolved during the remineralization step.

The mineral elements contained in the pod can be in the form of a concentrated mineral solution, but are preferably in the form of a dry powder. These are minerals commonly contained in mineral waters, for example in the form of carbonates, bicarbonates, hydroxylates, chlorides or sulphates of calcium, magnesium or sodium mainly.

The predefined volume of mineral water is a volume on a domestic scale, that is to say of the order of a liter, such as for example a volume less than 10 L, preferably less than 5 L, for example between 0.5 and 1.5 L, i.e. an amount easy to store in a carboy, gourd, carafe or bottle for household use. If necessary, you can first filter the impurities from the tap water. The impurities in question here can be soluble impurities, for example traces of organic micro-pollutants, such as pesticides, hydrocarbons, or traces of heavy metals such as cadmium or lead.

The impurities can also be insoluble, such as, for example, debris of microorganisms, precipitated heavy metals or mineral aggregates.

A dry powder of minerals here refers to a very fine powder, composed of particles having diameters of the order of a few microns, for example 5 to 200 microns, which have a high fluidity and whose volume can be measured, so very similar to liquid solutions. This particle size allows almost instantaneous dissolution.

The applicant also intends to protect a domestic appliance for the implementation of the method of the invention. This is a domestic appliance for producing a predefined volume of mineral water comprising

a circuit for circulating water from one inlet to at least one outlet, said inlet being provided with an inlet valve to be connected to a water inlet point and said outlet being provided with an outlet valve , circuit passing through a remineralization unit comprising at least one cavity for inserting a removable pod containing a determined quantity of mineral elements, cavity through which the water circulation circuit passes and arranged so that said circuit passes through the pod when it passes. - this is inserted into the cavity;

- Means for introducing carbon dioxide upstream or at the level of the insertion cavity of a pod;

the apparatus being characterized in that the water circulation circuit (2) comprises enzymes catalyzing the reaction of carbon dioxide and water to form carbonic acid and then bicarbonate, arranged downstream or at the level means (7) for introducing carbon dioxide.

The enzymes can for example be housed in a cartridge through which the water circulation circuit passes.

The apparatus may include a demineralization unit upstream of the water recirculation circuit, that is to say at the start of this circuit, after the water inlet. Preferably, the inlet valve is arranged to take a predefined volume of city water. The predefined volume of tap water is proportional to the quantity of mineral elements contained in the pod.

The pod is removable, i.e. it is not supplied with the device, but must be inserted each time the device is used. The pod is, by definition, for single use, that is to say that it contains a quantity of minerals adapted to the volume of water to be mineralized, for example just the quantity of mineral elements necessary to remineralize, at a determined mineral content, the predefined volume of treated water, that is to say tap water and demineralized, at least in part.

By domestic is meant here that the device is not suitable for industrial production and has a production capacity and dimensions allowing it to be installed in a private dwelling or at a workplace, to provide electricity. mineral water to a limited number of people. The device can also be adapted for catering or placed in the public domain.

In some cases, the pH of the city water is far from the pH of the mineral water to be produced, the pH of the remineralized water must be adjusted. In some cases, it is also necessary to adjust the pH of the demineralized water before re-mineralization to optimize the dissolution of the mineral elements.

The pH adjustment can be acidification or basification. Basification can be done for example by adding a volume of basic solution. The acidification can for example be carried out by injecting a volume of acidic solution, but is preferably obtained by introducing carbon dioxide before the remineralization. The introduction of carbon dioxide can be done upstream or at the level of the pod, by direct injection or any other suitable technique.

Enzymes have been shown to improve the dissolution of CO2 in water and to accelerate the acidification of the water as well as to achieve lower pH, thus avoiding the use of acidic solutions, which are not recommended for home use.

The remineralization step of the process according to the invention involves the use of an enzyme catalyzing the reaction of carbon dioxide and water to form bicarbonate. The enzymes catalyzing the reaction of carbon dioxide and water to form carbonic acid and then bicarbonate are preferably carbonic anhydrase. This enzyme, of class EC 4.2.1.1, is well known for improving the rate of dissolution of CO2 in water but has never been used in combination with means for injecting mineral powder to optimize their dissolution.

The Applicant also seeks to protect the removable pod containing a determined amount of mineral elements. Several embodiments are possible depending on the applications and the configuration of the device. Nevertheless, all the embodiments have the common characteristic of being arranged so that the predefined volume of water to be remineralized can flow through. It is therefore made either of porous materials or of a non-porous material that can be pierced, or a combination of the two. The pod is preferably for single use. When the volume of water to be remineralized passes through the pod, substantially all of the minerals it contains are dissolved.

The removable pod can advantageously contain enzymes which catalyze the reaction of carbon dioxide and water to form bicarbonate.

The different embodiments will be detailed below.

The invention will be better understood with the aid of the following description of several embodiments of the invention, with reference to the accompanying drawing, in which:

FIG. 1 is a block diagram of the method of the invention;

Figure 2 is a diagram of the apparatus of the invention;

Figure 3 is a perspective view of the apparatus of Figure 2; Figure 4 illustrates, perspective view from above, a pod according to

1 invention;

Figure 5 is a perspective view from below of the pod of Figure 4, and

Figure 6 is a sectional view of another pod according to the invention.

THE volume of water to be mineralized is preferably demineralized water. The term “demineralized water” designates water with a low mineral content or even devoid of minerals, and in particular of magnesium and calcium. The low mineral content can be obtained naturally, for example for spring water, or artificially, by desalination processes such as reverse osmosis, the use of resins, evaporation and recondensation. A low mineral content preferably corresponds to a dry mineral residue of less than 500 mg / L and more preferably still of less than 100 mg / L. Depending on the regions or the origin of the water (city water, spring water, etc.), it is therefore not essential that the water introduced into the device or used in the method be demineralized, since its mineral content is already extremely low.

The method of producing mineral water of the invention is preferably applicable for domestic, and not industrial, use. The quantity of mineral water to be produced remains limited to the consumption of a household, or even a business. It makes it possible to produce a limpid mineral water, having a taste chosen by the user, a taste involving a particular composition.

The method of producing mineral water of the invention is almost instantaneous. By snapshot, we must understand immediately, in the seconds that follow. The process thus differs from processes in which an internal tank is first filled in order to mix it with a mineral concentrate before being able to take off mineral water. It also differs from processes involving minerals in the form of solid salts, and whose dissolution can take several minutes or hours before giving a limpid mineral water. The process of the invention makes it possible to obtain one or even several liters of mineral water per minute.

With reference to FIG. 1, the process for producing a predefined volume of mineral water, possibly having a determined mineral element content, from here for example a tap water, having an inappropriate mineral element content and a known pH, comprises several steps.

In a first step A, a user expresses his desire to take mineral water, which triggers the production process. A system inlet valve will open until a predefined volume of tap water enters the system.

In a step B, optional for the implementation of the method of the invention, the impurities of the tap water are removed to obtain purified water, the volume of which is substantially identical to the predefined volume of tap water. taken. The techniques specifics of the purification step depend on the quality of the city water. The purpose of the purification step is to remove suspended matter, residual chlorine and other components such as heavy metals.

In a step C, optional for the implementation of the method of the invention, the volume of purified water is demineralized by partial or total elimination of minerals, in order to remove the undesirable components which are not eliminated by the step of purification. These components are mainly monovalent and bivalent ions. The demineralization step can be carried out using the reverse osmosis technique, which tends to remove all of the minerals, or using ion exchange resins, which allows selective demineralization. The choice of technique is here again determined from the compositions of the tap water and the mineral water to be produced.

In step D, the volume of demineralized water is remineralized by passing it through a removable pod containing a determined amount of mineral elements. The mineral elements contained in the pod are then completely dissolved in the volume of water passing through the pod. The determined quantity of mineral elements which is then dissolved makes it possible to obtain, in the predefined volume of water, the desired mineral content, that is to say corresponding to the chosen mineral water.

In some cases, carbon dioxide, in gaseous form, can be injected into the volume of water just before or at step D for pH regulation. Indeed, the dissolution of carbon dioxide in water allows the formation of bicarbonate, which makes it possible to reduce the pH of the water. This step may be necessary to promote the dissolution of the minerals in step D or to substantially acidify the demineralized water, when the pH of the mineral water to be produced is relatively acidic and the carbonate ions cannot be supplied. only by species dissolved in the concentrated mineral solution.

In step E, the volume of remineralized water is introduced into a suitable container, optionally placed at a place provided for this purpose by the user. When the preset volume of mineral water has been product, the mineral water production process stops, and the pod can be removed or ejected from the system.

With the aim of minimizing the accumulation of water during production, all stages take place "in line", that is to say that the water circulates in (almost) permanently and is not not immobilized during the process. The remineralization must therefore be almost instantaneous or at least very rapid. The user should not wait several minutes before being able to recover the volume of mineral water produced.

Several optional steps are also inserted here between re-mineralization D and sample E.

In the case where the mineral water to be produced is carbonated water, a gasification step H is introduced after the re-mineralization.

The consumer can have the choice to take water at room temperature, that is to say at room temperature, or chilled water. A cooling step G can then take place. G cooling can optionally be implemented before or after H gasification.

These steps A to H will thus be implemented each time a consumer wishes to take a predefined volume of remineralized water and inserts a pod.

This predefined volume is preferably constant and determined once and for all for a given system. Alternatively, it may be possible to predefine in the system several volumes, which would be produced, for example, at the choice of the user or according to information contained in the pod.

A number of preliminary steps can be implemented by the user to enable the production of the desired mineral water.

The consumer, in step I, inserts a pod of mineral elements corresponding to the mineral water he wishes to produce.

On the other hand, in a step J, the mineral content and the pH of the city water distributed where the method will be implemented can be analyzed. Usually, this information is available and regulatory analyzes should take place on a regular basis. This makes it possible to define the necessary demineralization steps. However, for a more universal method, notably using reverse osmosis as a demineralization technique, it is not necessary to know the mineral content of the tap water if the water is substantially demineralized. Conversely, in regions where city water is example resulting from desalination of sea water, its mineral content may be low enough that no demineralization step is necessary.

If step J is implemented, the predefined content and the content of the tap water are then compared in a step K to determine the surplus or excess minerals to be removed and the missing minerals to be added. . From this determination, the method of demineralization, total or partial of step C is determined.

Likewise, by comparing the pH of the desired mineral water and the supplied tap water, it is possible to determine the necessary pH adjustment.

For example, Table 1 details the composition of tap water distributed in the municipality of Uccle and compares it to that of Evian registered trademark water and Gerolsteiner registered trademark water.

Table 1.

The comparison indicates that the city water contains an excess or a defect, according to the mineral water compared, of sodium ions (Na ⁺ ), potassium (K ⁺ ), sulphates (SO ₄ ² ), chlorides (Cl), nitrates (NO ₃ ) calcium (Ca ²⁺ ), magnesium (Mg ²⁺ ) and bicarbonate (HCO ₃ ). The lack of bicarbonates is partly responsible for the difference in pH between the waters.

To produce mineral water substantially similar to Evian water, using water from the city of Uccle, it is possible to carry out demineralization by reverse osmosis. 99.5% of the ions contained in Uccle city water are thus eliminated. Demineralization here is almost total. To appropriately remineralize the reverse osmosis water, the content of mineral elements in the pod is defined in relation to the predefined volume of mineral water to be produced. Since inorganic elements are not accessible in their pure ionic form, it is important to choose the salts or anion-cation pairs in an appropriate manner, according to their solubility.

The element magnesium can, for example, be provided by several saline species: magnesium sulfate (MgS0 ₄ ) hepta-hydrate and magnesium bicarbonate (Mg (HC0 ₃ ) 2) This is also the case for calcium, supplied in the form of nitrate (Ca (N03) ₂ ) and in the form of bicarbonate (Ca (HCO3) ₂ ). Sodium can be supplied in the form of chloride (NaCl) and bicarbonate (NaHCOs) and potassium in the form of bicarbonate (KHC03). Depending on the desired pH, it is possible to adjust the composition by instead using bicarbonate salts, imparting a certain acidity, or rather hydroxides.

It is also possible to treat Uccle water to obtain water similar to Gerolsteiner trademark water. Geroldsteiner water contains much more mineral elements by weight than Evian water, in particular calcium, magnesium and bicarbonate. Its pH is also lower.

In order for the dissolution of minerals to be possible, in a limited time, it is possible to use in the process a step of dissolving CO2 using enzymes catalyzing the reaction of carbon dioxide and water to form carbonic acid then bicarbonate. These enzymes are preferably carbonic anhydrase. This enzyme, of class EC 4.2.1.1, is well known for improving the rate of dissolution of CO 2 in water but has never been used in combination with means for injecting mineral powder to optimize dissolution.

These enzymes can be used upstream and / or at the level of the passage of the volume of water through the pod containing the mineral elements. A means of introducing CO 2 into the water to be remineralized is then necessary.

The steps of the method having been described, an example of a system allowing its implementation will now be presented.

With reference to FIG. 2, the apparatus 100 comprises a connection port 1 for connecting the input of circuit 2 to the water supply network. city. Circuit 2 passes through a cartridge 3 of granulated activated carbon, a reverse osmosis unit 4 and a re-mineralization unit 5. A pump 6 and a carbon dioxide diffuser 7, connected to a carbon dioxide cylinder 8 via a valve 9, are here inserted between the demineralization unit 4 and the re-mineralization unit 5. At the outlet of the re-mineralization unit, circuit 2 passes through a cooling unit 11 before dividing into two sub-circuits 2a and 2b. The sub-circuit 2a leads to the outlet valve 13 of cooled water and the sub-circuit 2b passes through the gasification unit 15, connected to the carbon dioxide bottle 8 by a valve 19, before reaching the valve outlet 14 of carbonated cooled water.

In the re-mineralization unit 5, the circuit passes through a cavity into which can be inserted a removable pod 18 containing mineral elements.

Here is installed upstream of the pod 18 a cartridge 10 containing enzymes catalyzing the reaction of carbon dioxide and water to form carbonic acid and then bicarbonate. These enzymes are preferably carbonic anhydrase.

However, cartridge 10 is optional. Since all mineral waters do not have such a low pH or such high minerality as Gerolsteiner water, it is possible to introduce the enzymes which catalyze the reaction of carbon dioxide and water to form carbonic acid only in the pod, if necessary, in variable quantity depending on the mineral content of the pod.

The diffuser 7, like the saturator 15, can be a membrane contactor. They can be replaced by a single membrane contact device placed upstream of the enzyme cartridge 10 and of the pod 18.

Referring to Figure 3, all the elements of the device are contained in a box 20, having on its surface the connection port 1 (not shown), preferably at the rear of the box, and a control panel 21, on the front of the box, on which are arranged a button 22 for controlling still cooled or cooled water, a button 23 for controlling cooled carbonated water. The front of the case comprises a recess forming a platform 25. On the upper part of the case, a slot 24 is here provided for inserting a pod of minerals into the insertion cavity (not shown). This insertion cavity is preferably designed to be reclosable so as to allow the flow of water to pass only through the pod. The particular arrangement of the pod insertion cavity depends on the type of pod used. Examples will be described below.

A user or consumer places a container on the platform 25 of the device, inserts a pod of mineral elements into the slot 24 and starts the production of water by pressing one of the buttons 22 or 23 depending on whether the desired water is to be to be carbonated or not. Connection port 1, here a solenoid valve, opens to allow the entry of the predefined volume of city water, for example 1 L, in circuit 2.

For example, the triggering of the production of mineral water causes the closure of the insertion cavity of the pod so as to allow the flow of water to pass only through the pod.

The city water first passes through the cartridge 3 of granulated activated carbon where it is purified there by removing the residual chlorine as well as other pollutants such as lead. A micron filter (not shown) is for example associated with this cartridge in order to eliminate all the particles possibly suspended in the tap water. The water thus purified then passes through unit 4 comprising one or more reverse osmosis cartridges allowing the water to be freed of 99.5% of its minerals. The pump 6, placed downstream of the demineralization unit 4, provides the water flow and the pressure differential necessary for the operation of the reverse osmosis cartridges.

The demineralized water then passes through a carbon dioxide diffuser 7, if the pH must be lowered before re-mineralization, the valve 9 connecting the diffuser 7 to the carbon dioxide bottle 8 is opened to allow injection , continuously during production, at a precise flow rate of CO 2, which, when dissolved, forms part of the required bicarbonate.

The demineralized water then enters the re-mineralization unit 5. It passes through the cartridge 10 containing enzymes catalyzing the reaction of carbon dioxide introduced just before and water to form carbonic acid and then bicarbonate, in order to lower the pH of the water. Lowering the pH here not only makes it possible to reach the desired pH value, but also to facilitate the dissolution of the salts downstream. Such a cartridge 10 may for example contain the enzymes grafted onto beads and retained by a sieve / membrane, or grafted onto the walls of polymeric hollow fibers. Several types of suitable cartridges are described in application BE2019 / 5240.

The water enriched with bicarbonates then passes through the pod 18 containing minerals. Once all of the predetermined volume has passed through the pod, substantially all of the minerals it contained are dissolved in the water.

The carbon dioxide is added here upstream of the remineralization unit, by injection, but it could be injected directly at the level of the pod or of the cavity in which the pod is inserted. It could be added by infusion through a membrane permeable to carbon dioxide, or any other suitable means. After remineralization, depending on the consumer's initial choice, the water goes to one of the outlet valves 13 or 14.

If the user has pressed the button 22 in order to obtain cooled still water, the valve 13 is open. The water current then follows circuit 2 and passes here through an aluminum thermoelectric module allowing the water to be cooled between 5 ° C and 10 ° C. The cooled water then takes the sub-circuit 2a before exiting through valve 13.

If the user has pressed key 23, valve 14 is open. As described above, the water is first cooled and then passes through a saturator 15 into which carbon dioxide gas is injected at high pressure. The flow of carbon dioxide is controlled by valve 19 and is injected either continuously or by pulses at regular intervals. The carbon dioxide dissolves in cooled mineral water before leaving the sub-circuit 2b through valve 14.

Alternatively, obtaining still or sparkling water may not be left to the choice of the user, but depend on the pod which could integrate a tag recognized by the device and which would generate the implementation of certain functions of the device. device, such as gasification. Likewise, this tag could tell the machine how much water to produce.

The outlets corresponding to the valves 13 and 14 are preferably pipes assembled, either in a single opening or juxtaposed, above the platform 25. Their opening is arranged vertically downwards so that the water produced falls into the container. placed by the consumer on the platform. Production is almost instantaneous, pressing one of the control keys therefore causes the inlet valve 1 and an outlet valve 13 or 14 to open almost simultaneously.

Another outlet valve can also be envisaged, allowing the supply of temperate water, that is to say at ambient temperature. In this case, the remineralized water passes directly from the remineralization unit to the tempered water outlet valve.

It can be provided that the cooling units operate continuously, so that cold water is instantly available.

Provision can also be made, for the sake of energy saving, for these units to operate only on demand. In this case, a short delay can be programmed between the moment when the user presses the key of his choice and the moment when the production of mineral water begins, in order to allow the cooling unit to heat up. The apparatus preferably comprises means for ejecting the pod after its use. For example, a pod recovery bin, to be emptied regularly by the user, can be provided.

The pod can be introduced inside the cavity of the device using a pod holder, which can, for example, make it possible to optimize the alignment of the pod with the different water circulation channels .

The various elements of the apparatus are preferably arranged to minimize the total volume of the circuit in order to avoid dead volumes. Indeed, the dead volumes are conducive to the development of algae or bacteria, which is not desirable.

A purge function could also be provided, in order to "clean" the system after prolonged non-use, or when replacing certain parts of the device, or to empty any water remaining in the device after use.

The various elements of the apparatus can be replaced by any other element or system having the same function and making it possible to obtain the same result.

The cooling unit is not limited to an aluminum thermoelectric module. Any other technique making it possible to cool the water circulating in the sub-circuit 2b can also be envisaged.

The saturator is described here downstream of the cooling unit, but it could also be integrated into this unit, and could be the same element as the diffuser 7. A certain number of components of the system are advantageously linked to an electronic control unit. This is for example the case for all the inlet and outlet valves as well as the valves connected to the carbon dioxide cylinder, the pump 6 and the cooling unit 11. The electronic unit can thus be used to manage. the flow rates in the various circuits and sub-circuits.

The apparatus of the invention may be constructed in a standard form including all functionality. Depending on the composition of the town water of the installation municipality and the desired mineral water, it can be programmed so that only certain functions are used.

The different types of pods, essential complementary elements of the apparatus and of the method will now be described.

Pods are, by definition, consumable, single-use, small, and home-use items. A pod contains the quantity of mineral elements necessary to remineralize at a determined content, a predefined volume of water, preferably demineralized water.

According to a first embodiment, with reference to Figures 4 and 5, a pod 58 is arranged in the form of a rigid capsule, preferably cylindrical, having a section of the order of a few centimeters. This capsule 58 comprises a water inlet opening 51, which can be perforated or perforable to allow the entry of water, and, on the opposite portion of the capsule, a water outlet opening 52, which can also be perforated or perforable to allow water to escape. Inside the capsule 58 are contained powdered minerals 53 and here also enzymes 54 of carbonic anhydrase type. The water outlet opening 52 is also here provided with a membrane 55 permeable to dissolved minerals, but not to enzymes.

For the use of the pod, the cavity for inserting the pod in the apparatus described above can be configured with a movable rigid pipe which is placed so as to form a tight connection against the inlet opening of the pod. water from the pod when the process is carried out, or a rigid mobile pipe which perforates the portion of the capsule provided for this purpose, to likewise form a sealed connection. Such systems are in particular known and used for coffee pods. The capsule may also include an additional carbon dioxide inlet opening, or a pierceable portion to allow injection of carbon dioxide. This is not necessary, however, if the complementary pod device is designed to inject CO2 upstream of the capsule insertion cavity.

The volume of the capsule may be just sufficient to contain the minerals, evenly spread over the section of the capsule, but preferably the volume of the capsule is greater than the volume of the powdered minerals, so that it can serve as a micro- reactor by increasing the residence time of the water to be remineralized in the capsule.

The advantage of a rigid capsule thus configured is also that it can withstand a certain pressure of carbon dioxide inside.

If the complementary apparatus of the capsule comprises a cartridge with enzymes catalyzing the reaction of carbon dioxide with water, it is obviously not necessary to provide additional carbonic anhydrase in the capsule.

Likewise, the carbonic anhydrase is introduced here in a free form, and a particular membrane is added at the level of the outlet opening of the capsule, but the carbonic anhydrase could be introduced in a “supported” form, ie. i.e. grafted onto beads or even on the internal wall of the capsule, so that a simple filter preventing the passage of the beads at the capsule outlet would be sufficient, or even that the enzymes are grafted onto the membrane placed at the exit of the capsule.

The capsule may contain inert supports covering the section of the pod to keep the mineral powders spread over this section.

The water inlet and outlet openings have been shown here arranged in the center of the opposite flat faces of the cylinder forming the capsule. However, any other arrangement, preferably through, is also possible. The capsule could also have other shapes, such as an oval, square or rectangle section for example. A “puncture” capsule allows mineral elements to be stored away from humidity, without any additional packaging being necessary. However, this option is also possible.

The capsule is preferably made from recyclable materials.

For example, to produce 1 L of Evian-type water, a capsule can contain, in powder form, 7 mg of sodium chloride (NaCl), 8 mg of sodium hydrogencarbonate (NaHCO3), 3 mg of hydrogencarbonate. potassium (KHC03), 26 mg of magnesium sulphate heptahydrate (MgS04.7H20), 76 mg of magnesium carbonate (MgC03) and 195 mg of calcium carbonate (CaC03), i.e. 321 mg of powder occupying a volume of approximately 0.12 cm ³ . To ensure the total and rapid dissolution of these minerals, 0.1 to 18 pmol of carbonic anhydrase are added to the pod, in the form of free enzyme.

The capsule has a circular section 3 cm in diameter, ie a section of approximately 7 cm ² , which allows the mineral powder to be distributed over a thickness of approximately 0.02 cm.

According to a second embodiment, with reference to FIG. 6, a pod 68 is made of flexible or flexible materials. Powdered mineral elements 61 are immobilized between two layers 62 and 63 of a porous material, layers sealed together on the periphery of the pod. The porosity of the material is low enough to retain the mineral powder while allowing water to pass through.

The mineral composition described for the first embodiment of the pod can also be used in this type of pod, to produce water similar to the Evian trademark water. The enzymes are here, preferably, part of the complementary apparatus of the pod, for example in a cartridge 10 illustrated in FIG. 3, or are introduced into the flexible pod in supported form, that is to say grafted onto marbles .

The advantage of a flexible pod is that, once all the minerals have dissolved, only the porous material remains as a single waste, which makes it easier to process or recycle the pod. The apparatus according to the invention, when it is intended to receive a flexible pod, may comprise, in the pod insertion cavity, means for maintaining the pod, such as for example means for exerting pressure on the pod. each side of the pod so that it stays in place during the production of mineral water.

Claims

1. Process for producing a predefined volume of mineral water, comprising the following steps:

-on mineralized (D) a predefined volume of water by passing it through a removable pod containing a determined quantity of mineral elements, so as to dissolve the mineral elements contained in the pod,

process characterized by the fact that: - carbon dioxide is introduced before or during the remineralization and

2. Method according to claim 1, wherein one demineralizes (C), at least in part, a predefined volume of water prior to mineralization and the introduction of carbon dioxide, to obtain a predefined volume of demineralized water. .

3. Method according to one of claims 1 and 2, wherein the predefined volume of mineral water has a predetermined mineral content.

4. Domestic apparatus (100) for producing a predefined volume of mineral water comprising

a circuit (2) for circulating water from an inlet (1) to at least one outlet (13, 14), said inlet being provided with an inlet valve to be connected to a water inlet point and said outlet being provided with an outlet valve (13, 14), a circuit passing through a remineralization unit (5 comprising at least one cavity for inserting a removable pod (18) containing a determined quantity of mineral elements, cavity crossed by the water circulation circuit (2) and arranged so that said circuit passes through the pod when the latter is inserted into the cavity;

- Means (7,9) for introducing carbon dioxide upstream or at the level of the insertion cavity of a pod (18);)

apparatus characterized in that the water circulation circuit (2) comprises enzymes catalyzing the reaction of carbon dioxide and water to form carbonic acid and then bicarbonate, arranged downstream or at the level of the means ( 7) introduction of carbon dioxide.

5. Apparatus according to claim 4, wherein the enzymes are housed in a cartridge through which the water circulation circuit passes.

6. Apparatus according to one of claims 4 and 5, wherein the insertion cavity of a removable pod (18) is resealable in a waterproof manner and so as not to allow the passage of the water flow. than through the pod.

7. Apparatus according to one of claims 4 to 6, wherein the insertion cavity of a removable pod (18) is equipped with means for perforating a removable pod (18).

8. Apparatus according to one of claims 4 to 7, further comprising a demineralization unit upstream of the water circulation circuit.

9. Apparatus according to one of claims 4 to 8, wherein the inlet valve is arranged to be connected to a city water inlet point.

10. Disposable drinking water remineralization pod (58, 68) containing a determined amount of mineral elements (53, 61) and enzymes (53) that catalyze the reaction of carbon dioxide and water to form baking soda.

11. Pod according to claim 10, wherein the minerals are in powder form, the particles of which preferably have a particle size of between 5 to 200 microns.

12. Pod (58) according to one of claims 10 and 11, in the form of a rigid capsule.

13. Pod according to one of claims 10 to 12, arranged with an opening (51) for water inlet and an opening (52) for water outlet, said openings being open and / or pre-perforated.

14. Pod according to one of claims 10 to 13, comprising inert supports covering the section of the pod to keep the mineral elements spread over this section.

15. Pod (68) according to one of claims 10 to 14, wherein the mineral elements (61) are between two layers (62, 63) of a porous material, said layers being sealed together around the periphery of the pod.