Apparatus and system for carbonating liquids

Abstract

The utility model relates to a device and a system for carbonating liquid. The device comprises an inlet for supplying a liquid to be carbonated, a feeder for a gas, in particular CO2, where the gas is used for carbonating the liquid, and an outlet for discharging the carbonated liquid, the carbonated liquid being a mixture of liquid and gas. Furthermore, an annular gap is provided between the inlet and the outlet, and the device further comprises a displacement body which is axially movable in the flow direction of the liquid such that when the displacement body is moved, the opening area of the annular gap through which the liquid passes can be changed. The utility model also relates to a method for carbonating a liquid.

Description

TECHNICAL FIELD

[0001] The present invention relates to a device and a system for carbonating a liquid. BACKGROUND

[0002] In conventional apparatuses for carbonating a liquid, in particular a beverage, such as a soft drink or a juice-mix drink, so-called CO2 cavitation injectors can be used. These injectors have a narrowing (or constriction) and a subsequent widening of the flow cross-section in the flow path of the liquid. At the narrowing, for example in the form of an annular gap, the static pressure of the liquid is reduced due to the Venturi effect and can be reduced below the vapor pressure, resulting in gas or vapor bubbles. This effect is also called cavitation effect. When the flow cross-section is increased again, the static pressure rises again above the vapor pressure, the bubbles implode and break up into smaller units. This leads to a particularly fine and stable solution of CO2 in the liquid. In order to further enhance the cavitation effect, a plurality of narrowings can be arranged in the flow direction, each followed by a widening. Cavitation injectors are known, for example, from EP 1 749 564 A2, EP 2 135 667 A1 and EP 1 280 598 A2.

[0003] A prerequisite for these cavitation injectors is usually that the liquid requires a high flow rate. Therefore, a high pressure has to be applied, which means an energy-intensive operation. Furthermore, due to the narrowings or annular gaps, the cavitation injectors have a plurality of undercuts which are difficult to clean. An alternative is an injector with a narrowing, in which CO2 is introduced into the liquid at or after the narrowing (seen in the flow direction) and dissolved therein. This injector has a simple and easy-to-clean structure, however, it is less suitable for easily foaming beverages, since it only achieves an insufficient CO2 saturation of the liquid. Although this disadvantage can be compensated by cooling the liquid, the energy consumption is also increased. SUMMARY

[0004] OBJECTIVE

[0005] In view of these disadvantages, it is desirable to use an injector for carbonating a liquid which achieves a high quality of the carbonated liquid without having to accept the disadvantages of poor cleaning and high energy consumption discussed. It is therefore an object of the present invention to produce a carbonation of a beverage (or generally liquid) with a high CO2 saturation in an energy-saving and hygienic manner.

[0006] SOLUTION

[0007] According to the invention, a device for carbonating a liquid is provided, comprising an inlet for supplying a liquid to be carbonated, a feeder for a gas, in particular CO2, wherein the gas is used for carbonating the liquid, and an outlet for discharging the carbonated liquid, the carbonated liquid being a mixture of the liquid and the gas, wherein an annular gap is arranged between the inlet and the outlet. The device further comprises a displacement body, which is axially movable along a flow direction of the liquid, such that the opening area of the annular gap through which the liquid passes can be varied when the displacement body is moved.

[0008] The device is a syringe, the opening area of the annular gap of which is variable depending on the axial position of the displacement body. By the opening area, it is also possible to set at the same time whether the syringe is operated in a cavitation state or not, since cavitation only occurs when the static pressure in the region of the annular gap falls below the vapor pressure. Thus, the syringe described here can be operated both inside and outside the cavitation state, also called normal state, and can be adapted to the requirements of the respective liquid by the position of the displacement body and the pressure at which the liquid is supplied. For example, products which do not tend to or only tend to form foam to a small extent can be carbonated without cavitation, thus produced in an energy-saving manner (since the liquid requires a lower pressure, thus a lower pumping capacity). By improving the dissolution of CO2 in the liquid, liquids which tend to form foam can be produced in the cavitation state. Furthermore, the syringe can have only one gap, whereas the prior art has multiple gaps. Thus, the device described here can be cleaned more easily and thus can be constructed more hygienically. Liquids which tend to form foam are, for example, red mixed drinks (red dyes tend to form foam due to their usually high protein content) or root beer, or generally liquids which have a high oxygen content, in particular more than 2.5 ppm.

[0009] The device can be used for the carbonation of, for example, beverages, wherein the liquid in particular comprises water. In order to produce soft drinks or juice mixed drinks, the water can in particular be mixed with a concentrate of other ingredients, such as a syrup or a fruit concentrate.

[0010] The mixture of the liquid and the gas in particular denotes the case that the gas is dissolved in the liquid.

[0011] The annular gap can be formed by the opening between the inlet and the outlet being partially closed by the displacement body. The annular gap is then arranged between the outside of the displacement body and the boundary of the inlet and the outlet. The opening area of the annular gap thus denotes the area between the outside of the displacement body and the boundary of the inlet and the outlet through which the liquid can flow. Another name for the opening area is the opening cross section. The annular gap can be a narrowing in which the cross section through which the liquid flows has a local minimum. This in particular means that the cross section upstream and downstream of the annular gap is larger than the opening area of the annular gap. The cross section downstream of the annular gap can be 10% to 50% larger than the opening area of the annular gap.

[0012] The device can comprise a housing. In this case, the inlet and the outlet can be formed as passage openings through the housing, and the annular gap represents a narrowing of the passage openings.

[0013] A gas feeder can be arranged downstream of the annular gap. In particular, the feed can lead into the flowing liquid or the region of the flowing liquid. In this case, the gas can be introduced into the liquid or the region of the flowing liquid through one or more openings, such as holes or slots. Furthermore, the feed can be arranged in such a way that the gas is introduced into the liquid through an outer restriction of the outlet.

[0014] Downstream of the annular gap, the cross section of the surface through which the liquid flows is larger than at the annular gap. As previously described, the static pressure of the liquid is reduced at the narrowing, and thus, in the case of cavitation operation, gas bubbles are generated in the liquid when the static pressure falls below the vapor pressure. The gas now flows into the partially gaseous liquid, resulting in a steam-gas mixture. If the steam-gas mixture is now directed to a region having a larger cross section, the flow velocity decreases and the static pressure increases, as a result of which the steam-gas mixture condenses and, if the gas is in particular CO2, a carbonated (carbonated) liquid is formed. The special arrangement of the gas feed downstream of the annular gap therefore advantageously leads to the production of a carbonated liquid.

[0015] The device can further comprise a gas channel and a gas metering device, wherein the gas channel is arranged outside the outlet, and wherein the gas metering device is configured to adjust or control the amount of gas flowing from the gas channel into the liquid to be carbonated by changing the opening between the gas channel and the outlet.

[0016] The gas metering device offers the possibility of effectively adjusting and / or controlling the gas flow into the liquid without, for example, having to change the pressure of the gas provided in the feeder. The device can therefore be flexibly adapted to different requirements of the liquid to be carbonated. Exemplary embodiments of such a gas metering device are explained below with reference to the figures.

[0017] The displacement body can have a cross section that tapers in the flow direction. Alternatively, the displacement body can have a cross section that widens in the flow direction.

[0018] The tapering or widening cross section has a variable cross-sectional area in the axial direction. As a result, the opening area of the annular gap can be changed by a purely axial movement of the displacement body. This allows a simple and effective structural design of the device, in which the displacement body has to be movable only along the axis.

[0019] The displacement body can have a drive, in particular an electric, pneumatic or membrane drive. The displacement body can therefore be controlled mechanically and / or electronically and, in particular, if necessary, by an external device, such as a control unit and / or a computer, which makes an automated process possible.

[0020] The displacement body can have one or more recesses on its upstream side.

[0021] Due to the recesses of the smooth surface of the displacement body on the upstream side, the turbulence in the liquid flow increases (turbulence). Thus, the cavitation effect can be improved.

[0022] The inlet and the outlet can be substantially perpendicular to each other, wherein the displacement body is movable in the flow direction within the outlet. The substantially perpendicular arrangement between the inlet and the outlet comprises an angle between 80° and 100° between the two elements.

[0023] Due to the angle between the inlet and the outlet, the device can be designed more compact and more stable as a whole. If the two components are substantially parallel, the displacement body has to be held along the inlet and the outlet over its entire length, which can be unstable. On the other hand, by the specified angle, the holder can be attached to the device and the displacement body only needs to protrude into the opening between the inlet and the outlet in order to form an annular gap there. This allows a shorter / more compact installation and improved stability of the holder.

[0024] The terms "narrowing" and "narrow" can be used synonymously in this description.

[0025] The diameter of the outlet can increase monotonically downstream at least in a portion.

[0026] With the increasing diameter of the outlet, the cross-sectional area of the region through which the liquid flows also increases at the same time. In the case of a constant pressure of the liquid, the monotonous increase in the cross-sectional area leads to a monotonous decrease in the flow rate and a monotonous increase in the static pressure. In this way, the gas (and, if necessary, the steam bubbles that are produced when the static pressure falls below the vapor pressure) is dissolved more uniformly in the liquid. The result is a finer product.

[0027] The outlet can be of an annular configuration, wherein the outlet can comprise a first portion downstream of the annular gap and a second portion adjacent downstream of the first portion, and wherein the second portion has a larger cross-section than the first portion.

[0028] This arrangement corresponds to a stepwise widening or increase in the flow cross-section or cross-sectional area through which the liquid flows from the first portion to the second portion. The advantages of better dissolution of the gas in the liquid and a finer foam product occur in the case of a monotonous increase in the cross-sectional area. Within the first or second portion, the cross-sectional area can be constant in each case, or alternatively, can increase as seen in the flow direction.

[0029] The device can further comprise a liquid outlet, which can optionally have a circular cross-section, wherein the liquid outlet is arranged downstream adjacent to the second portion of the outlet, and wherein the cross-section of the liquid outlet is larger than the cross-section of the second portion.

[0030] The liquid outlet in fact forms the end of the device into which the fully carbonated liquid is introduced. From there, it can be transferred into, for example, a buffer tank or a filling device. Furthermore, the further widening of the cross-section ensures that the gas is now fully dissolved in the liquid.

[0031] The described device can also comprise a sensor for receiving the acoustic signal generated by the device, wherein the sensor is arranged outside the outlet or inside the outlet, and wherein the sensor is configured to receive or generate the frequency spectrum of the acoustic signal.

[0032] During continuous operation, it is in principle not or hardly possible to determine whether the device is operating in cavitation mode. Furthermore, this mode depends on a number of operating parameters, in particular the flow rate of the liquid and the opening area of the annular gap. However, a device that is working in cavitation mode is acoustically different from a device that is not working in cavitation mode. Therefore, with the aid of a sensor for receiving the acoustic signal, an indication can be obtained as to whether the device is working in cavitation mode. Therefore, the device can comprise at least one sensor for receiving the acoustic signal.

[0033] The sensor can comprise a sound sensor, for example a hydrophone, a vibration sensor or a surface acoustic wave sensor.

[0034] The device can also comprise a control unit configured to compare the frequency spectrum received by the sensor with a predetermined reference frequency spectrum and to determine from the comparison whether the device is operating in cavitation state.

[0035] The sensor and the control unit can now together determine the mode during operation, so that the parameters can also be changed in due time if the desired mode is not present. This will be explained in more detail below.

[0036] Furthermore, the control unit can be configured to perform an adjustment of the device based on the comparison between the received frequency spectrum and the predetermined reference frequency spectrum, so that at least one of the following parameters is controlled and / or adjusted: the temperature of the liquid to be carbonated, the gas pressure in the feeder, the pressure of the liquid to be carbonated in the inlet and the opening area of the annular gap.

[0037] The control device thus provides a comprehensive possibility of controlling and / or adjusting the relevant operating parameters of the device. Therefore, the device can be used for a number of operating modes and is, for example, suitable for the carbonation of many different liquids.

[0038] The present application also provides a system for carbonating a liquid. The system comprises the device described so far, a mixing unit configured to degas water supplied and mix the degassed water with a concentrate to produce a liquid to be carbonated, a liquid pump unit for delivering the liquid to be carbonated to the device at an adjustable liquid feed pressure, a gas feeder for delivering or feeding gas to the device at an adjustable liquid feed pressure, and optionally, a filling device configured to fill the carbonated liquid into a container.

[0039] The system also solves the initially set purpose of producing carbonation of a beverage (or in general liquid) with high CO2 saturation in an energy-efficient and hygienic manner. In this case, the system comprises the described device and other components which are important for setting the operating parameters and which contribute to a high degree of flexibility and a variety of possible applications.

[0040] In particular, the system can comprise the device with a control unit which performs the adjustment of the device in this way based on a comparison between the received spectrum and a predetermined reference spectrum.

[0041] Furthermore, the system can comprise a buffer tank for storing the carbonated liquid at an adjustable buffer pressure. The control unit can be configured to control and / or adjust the difference between the feed pressure and the buffer pressure. The feed pressure can be the pressure upstream of the device, in particular at the inlet of the device. The buffer pressure can be an adjustable pressure in the buffer tank. Optionally, the buffer pressure can also be the pressure downstream of the device, in particular at the outlet of the device.

[0042] The pressure difference between the buffer pressure and the liquid feed pressure is an important parameter in the carbonation of liquids, different liquids having different optimal values. For example, liquids which tend to foam during carbonation or subsequently during filling require a higher pressure difference than liquids with a low tendency to foam. The possibility of adjusting (by adjusting and / or controlling) the pressure difference therefore increases the flexibility of the system.

[0043] Furthermore, the present application relates to a method for carbonating a liquid. The method comprises providing one of the above-described devices or systems, supplying a liquid to be carbonated through the inlet at a predetermined liquid feed pressure, and feeding gas for carbonating the liquid through the inlet at a predetermined gas feed pressure, wherein the position of the displacement body or the difference between the liquid feed pressure and the buffer pressure is set in a manner adapted to the liquid to be carbonated.

[0044] As with the described device, the method achieves the purpose of providing a method in which carbonation of a beverage (or in general liquid) with high CO2 saturation is produced in an energy-efficient and hygienic manner.

[0045] The term "in an adapted manner" is to be understood as meaning that the indicated operating parameters are chosen in such a way that, depending on the liquid to be carbonated, a certain gas concentration is achieved in the liquid, or that the foaming behavior is taken into account, for example in the case of subsequent filling of the carbonated liquid into a container. The parameters can be retrieved from a database, for example, or can be selected and set by a user.

[0046] Downstream of the annular gap, the cross section through which the liquid flows widens, so that the static pressure increases and the gas bubbles formed during cavitation implode again. In this process, a certain time is required until the gas is completely dissolved in the liquid, so that a uniform carbonation is achieved.

[0047] The method can further comprise the step of receiving, with a sensor, a frequency spectrum of the acoustic signal generated by the device and determining, depending on a comparison between the received frequency spectrum and a predetermined reference frequency spectrum, whether the device is working in a cavitation state.

[0048] During continuous operation, it is not possible or hardly possible in principle to determine whether the device is operating in a cavitation mode. However, a device working in a cavitation mode is acoustically different from a device not working in a cavitation mode. Therefore, with the aid of a sensor for receiving an acoustic signal, an indication can be obtained as to whether the device is working in a cavitation mode.

[0049] Based on the comparison between the received frequency spectrum and the predetermined reference frequency spectrum, the regulation of the device or system can be performed in such a way that at least one of the following parameters is controlled and / or regulated: the temperature of the liquid to be carbonated, the gas pressure in the feeder, the pressure of the liquid to be carbonated in the inlet and the opening area of the annular gap.

[0050] The method thus provides a comprehensive possibility of controlling and / or regulating the relevant operating parameters of the device. The method can thus be used in a variety of ways and is suitable, for example, for the carbonation of many different liquids.

[0051] The invention also provides a device, wherein the device comprises an inlet for supplying a liquid to be carbonated, a feeder for a gas, wherein the gas serves to carbonate the liquid, and an outlet for discharging a carbonated liquid, which is a mixture of the liquid and the gas. The device further comprises a constriction between the inlet and the outlet, wherein the cross section through which the liquid flows in the constriction is smaller than in the inlet and the outlet, and a sensor for receiving an acoustic signal generated by the device, wherein the sensor is arranged outside the outlet or inside the outlet, and wherein the sensor is configured to receive or generate a frequency spectrum of the acoustic signal.

[0052] This aspect of the invention relates to a device for carbonating a liquid, which does not have a variable displacement body according to the first described aspect of the invention, but has an acoustic sensor. As described before and shown in the detailed description of the following figures, the sensor is used to determine whether the device is operating in cavitation mode (corresponding to normal mode). Cavitation preferably occurs when the flow rate is large enough to drop the static pressure below the vapor pressure. Thus, the device can also be operated in two modes of operation, i.e. with or without cavitation. The purpose of initially setting the carbonation in an energy-saving and hygienic way to produce a beverage with a high CO2 saturation is also achieved with this form of the device.

[0053] The statements in this specification regarding the device, the system and the device also apply appropriately in the case where the device does not comprise a displacement body but a sensor. The advantages of these statements apply equally.

[0054] The device for carbonating a liquid can also comprise an inlet for supplying the liquid to be carbonated, a feeder for a gas, in particular CO2, wherein the gas serves to carbonate the liquid, and an outlet for discharging the carbonated liquid, which is a mixture of the liquid and the gas, wherein a gap or constriction is arranged between the inlet and the outlet.

[0055] The gap or constriction can be annular or circular.

[0056] The gas feeder can be arranged downstream and / or upstream of the gap or constriction.

[0057] The sensor can comprise an acoustic sensor, such as a hydrophone, a vibration sensor or a surface acoustic wave sensor.

[0058] The device can also comprise a control unit which is configured to compare the frequency spectrum received by the sensor with a predetermined reference frequency spectrum and to determine from the comparison whether the device is operating in a cavitation state.

[0059] Furthermore, the control unit can be configured to perform an adjustment of the device based on the comparison between the received frequency spectrum and the predetermined reference frequency spectrum, such that at least one of the following parameters is controlled and / or adjusted: the temperature of the liquid to be carbonated, the pressure of the gas in the feeder and the pressure of the liquid to be carbonated in the inlet.

[0060] Likewise, the control unit can be configured to control the displacement body by means of the above-mentioned drive (electric, pneumatic or diaphragm drive), to thereby adjust and / or adjust its position. This means that the axial movement is performed by the control unit. Thus, another possibility of selecting the device parameters can be provided, which increases the flexibility of the device. In particular, when the displacement body has a cross-section which tapers or widens, the opening area of the annular gap is influenced by its position.

[0061] The invention also provides a system for carbonating a liquid. The system comprises the device described so far, a mixing unit which is configured to degas water supplied and to mix the degassed water with a concentrate to produce a liquid to be carbonated, a liquid pump unit for delivering the liquid to be carbonated to the device at an adjustable liquid feed pressure, a gas feeder for delivering or feeding gas to the device at an adjustable liquid feed pressure, and / or a filling device which is configured to fill the carbonated liquid into a container.

[0062] The system can in particular comprise the device with a control unit which performs the adjustment of the device in such a way on the basis of a comparison between a received frequency spectrum and a predetermined reference frequency spectrum, and also a buffer tank for storing the carbonated liquid at an adjustable buffer pressure, wherein the control unit is also configured to control and / or adjust the difference between the feed pressure and the buffer pressure.

[0063] Furthermore, the invention relates to a method for carbonating a liquid. The method comprises providing the device or the system, supplying a liquid to be carbonated through the inlet at a predetermined liquid feed pressure, and supplying a gas for carbonating the liquid through the inlet at a predetermined gas feed pressure, wherein the method also comprises receiving an acoustic signal generated by the device with a sensor, and wherein the sensor is configured to receive or generate a frequency spectrum of the acoustic signal.

[0064] The method can also comprise the steps of receiving a frequency spectrum of the acoustic signal generated by the device with a sensor, and determining whether the device is working in a cavitation state on the basis of a comparison between the received frequency spectrum and a predetermined reference frequency spectrum. On the basis of the comparison between the received frequency spectrum and the predetermined reference frequency spectrum, the adjustment of the device or the system can be performed in such a way that at least one of the following parameters is controlled and / or adjusted: the temperature of the liquid to be carbonated, the pressure of the gas in the feeder, and the pressure of the liquid to be carbonated in the inlet.

[0065] Alternatively, the method can also be carried out as follows:

[0066] A method for carbonating a liquid, comprising the steps of:

[0067] supplying a liquid to be carbonated,

[0068] supplying a gas, in particular CO2, wherein the gas is used for carbonating the liquid, and

[0069] discharging the carbonated liquid, which is a mixture of the liquid and the gas,

[0070] passing the liquid through the annular gap after the supplying and before the discharging,

[0071] The displacement body is moved axially along the flow direction of the liquid, thereby changing the open area of the annular gap through which the liquid passes.

[0072] The method can also be performed by means of the above-described device and system. BRIEF DESCRIPTION OF DRAWINGS

[0073] Further features and advantages will be explained below by means of exemplary drawings. Therein:

[0074] Figure 1A a schematic side view of a device according to a first embodiment is shown;

[0075] Figure 1B a schematic cross section of a device according to a first embodiment is shown;

[0076] Figure 2 a schematic cross section of a device according to a second embodiment is shown;

[0077] Figure 3 a schematic partial side view of a displacement body for the device is shown;

[0078] Figure 4 a schematic cross section of a device according to a third embodiment is shown;

[0079] Figure 5 a schematic cross section of a device according to a fourth embodiment is shown;

[0080] Figure 6 a schematic view of a system comprising the device is shown; and

[0081] Figure 7 an exemplary comparison between the frequency spectrum of the reception in normal operation and the frequency spectrum of the reception in cavitation operation of the device is shown.

[0082] In the following and in the drawings, the same reference numerals are used for the same or corresponding elements in different embodiments, unless otherwise specified. DETAILED DESCRIPTION

[0083] Figure 1A a schematic side view of a device 10 for carbonating a liquid according to a first embodiment is shown. According to the present invention, the device 10 comprises an inlet 11 for supplying the liquid to be carbonated. The liquid to be carbonated can be, for example, water or a mixture of water and a concentrate for a soft drink or a juice mixed beverage. The entire device 10 is arranged in a housing 10a. In this case, the inlet 11 and the outlet 12 are tubular lines, which are adjacent to an intermediate space in which a displacement body is located (as will be shown later). The gap can also be assigned to the inlet 11. The inlet 11 and the outlet 12 pass through an annular gap 14 (see Figure 1B The gap can also be assigned to the inlet 11. The inlet 11 and the outlet 12 pass through an annular gap 14 (see Figure 1Bare separated from each other, although they are fluidically connected.

[0084] The device 10 also comprises a feeder 13 for gas, in particular CO2, which is used for carbonation of the liquid. The feeder 13 is located outside the housing 10a and directs the gas into the interior of the housing 10a or of the device 10. More precisely, the gas enters the outlet 12 through a plurality of optional circular or elongated holes 13a and is then mixed there with the flowing liquid.

[0085] Figure 1A The cross section of the device 10 is shown in Figure 1B particular. In particular, details about the annular gap 14 and the displacement body 15 can be seen. The displacement body 15 comprises a holder which is mounted on the housing 10a (or more generally on the device 10). The front part of the displacement body 15, which is connected to the holder by means of a connecting rod, has a cross section which tapers in the flow direction and is located at a narrowing (reduced cross section with respect to the inlet 11 and the outlet 12) between the inlet 11 and the outlet 12. Thus, due to the presence of the displacement body 15 in the narrowing, the annular gap 14 is formed. Due to the conical shape of the displacement body 15, the opening area of the annular gap 14 can be changed by axial movement of the displacement body 15. It should be noted that it is not necessarily necessary to provide a narrowing between the inlet 11 and the outlet 12; rather, the cross sections of the two elements can also be constant within the transition region. In this case, too, an annular gap is formed due to the presence of the displacement body 15.

[0086] The inlet 11 and the outlet 12 are essentially perpendicular to each other. A deviation from the right angle is also conceivable, in particular in the range between 80° and 100°. The advantages of this essentially right-angled arrangement are obvious in the design of the displacement body 15. The latter can be integrated laterally into the device 10 so that it is coaxially aligned with the outlet 12 and protrudes into the narrowing between the inlet 11 and the outlet 12, thus forming the annular gap 14. Thus, the fastening of the displacement body 15 can be significantly shorter compared to the case of a parallel running of the inlet 11 and the outlet 12, thus being simpler and more stable, since the displacement body has to be held along the entire length of the inlet 11. The drive (not shown) for the displacement body 15 can be provided outside the housing 10a, for example as part of the holder, in order to axially move the latter. The drive can be electric, pneumatic or diaphragm driven.

[0087] Figure 2A second embodiment of the device 10 according to the present application is shown. The main difference between this embodiment and the first embodiment is the design of the gas feeder 13. Therefore, only the differences between the two embodiments are discussed here and below. It should be noted that this figure shows the displacement body 15 in a position in which the annular gap 14 is (almost) closed. However, it should be understood that the displacement body 15 is axially movable and that the described configuration is not limited to a specific position of the displacement body 15.

[0088] The feeder 13 further comprises a gas channel 13b and a gas metering device 13c. The gas channel 13b is formed downstream of the annular gap 14 around the entire circumference of the outlet 12. Of course, the gas channel 13b can also be formed only around a part of the circumference of the outlet 12. The gas channel 13b is connected to the outlet via an opening 13d and the gas flowing in can be guided into the liquid flowing through the outlet 12 via the opening 13d. The size of the opening 13d can be adjusted by means of the gas metering device 13c. The size of the opening 13d determines the volume of gas introduced into the liquid, the maximum amount of gas that can be dissolved in the liquid and the flow rate of the gas through the opening.

[0089] In the embodiment shown, the gas metering device 13c comprises at least one grub screw with which an element can be moved axially along the outlet 12 between the outlet 12 and the gas channel 13b. As a result of this movement, the size of the opening 13d can be determined by adjusting the grub screw on the gas metering device. Thus, both adjusting the gas feed pressure in the feeder (see below) and adjusting the size of the opening 13d represent possibilities to influence the amount of gas dissolved in the liquid. The gas metering device 13c can be operated manually or by a control unit (see below).

[0090] As mentioned above, the displacement body 15 can have a cross-section that tapers or widens in the flow direction. Figure 3 Another example of the design of the displacement body 15 is shown. While in the previous exemplary embodiment no pattern was shown on the upstream side, a plurality of recesses 15a can also be located on this side. Here, a plurality of recesses 15a are located on the circumference of the upstream side, however, the present application is not limited to this specific shape and arrangement. Rather, one or more recesses can be provided which can also have a different shape. The significance of these recesses 15a is that the liquid flowing through rotates therein and thus more turbulent flow (as opposed to laminar flow) occurs. In the turbulent flow state, cavitation effects occur more easily and thus the device 10 can be operated at lower energy consumption. Lower liquid flow rates and thus lower feed pressures are sufficient to enter the cavitation state with otherwise identical parameters.

[0091] Reference is now made to Figure 4A third embodiment of the device 10 is explained. In this case, the outlet 12 is elongated compared to the previous embodiments and the cross section of the outlet 12 through which the liquid flows is configured annularly. The cross sectional area increases monotonously in the flow direction. The annular cross section of the outlet 12 is formed due to the displacement body 15 being arranged inside the outlet 12 along its entire length such that the liquid can only flow between the outside of the displacement body 15 and the boundary of the outlet 12. Furthermore, as mentioned above, the displacement body 15 forms the annular gap 14 between the inlet 11 and the outlet 12. In other words, the liquid is guided from the inlet 11 through the annular gap 14 into the likewise annular cross section of the outlet 12. Downstream of the annular outlet 12, the liquid outlet 16 is adjacent to the outlet 12, the liquid outlet 16 having a larger cross section than the outlet 12. The carbonated liquid can be delivered from the liquid outlet 16 to another device.

[0092] The displacement body 15 can be moved axially along the outlet 12. Furthermore, the displacement body 15 inside the outlet 12 can have an increasing diameter downstream (widening cross section). Thus, the axial movement of the displacement body 15 changes the cross sectional area of the region through which the liquid flows, which also leads to a change in the flow velocity and the static pressure. Thus, the axial movement of the displacement body 15 represents the possibility of adjusting the parameters of the device 10 in the outlet 12.

[0093] The monotonous increase of the cross section of the outlet 12 likewise leads to a monotonous increase of the static pressure and a monotonous decrease of the liquid flow velocity. As a result, the gas bubbles and vapor bubbles generated due to cavitation dissolve more slowly, in particular uniformly, in the liquid.

[0094] Figure 5 A fourth embodiment of the device 10 according to the invention is shown. This differs from the third embodiment in the design of the cross section of the outlet 12. Here, the cross section of the outlet 12 gradually gets larger downstream. The outlet 12 can be divided into two sections 12a and 12b. Downstream of the annular gap 14 is the first section 12a, wherein the cross section of the first section 12a is larger than the opening area of the annular gap 14. In the first section 12a there is also provided the feeder 13 through which gas is introduced into the flowing liquid, as well as the gas metering device 13c and one or more associated openings 13d through which gas is introduced into the flowing liquid. Adjacent to the first section 12a is the second section 12b having a larger cross section than the first section 12a.

[0095] The displacement body 15 is axially movable parallel to the outlet 12 and has a widening cross section as seen in the flow direction. Thus, not only the opening area of the annular gap 14 changes during the axial movement of the displacement body 15, but also the cross sectional areas of the first section 12a and the second section 12b. Thus, this device 10 has a high degree of flexibility and a plurality of adjustment possibilities for the associated cross sections.

[0096] Furthermore, by gradually enlarging the cross-sectional area of the outlet 12, a particularly uniform dissolution and distribution of the gas in the liquid can be achieved, as described before. In this embodiment, the residence time of the liquid in the portion 12a of the outlet 12 can be between 1 ms and 10 ms, in particular between 2 ms and 5 ms. In the portion 12b of the outlet 12, the residence time of the liquid can be between 10 ms and 50 ms, in particular between 20 ms and 30 ms. The optimal length of the two portions 12a and 12b of the outlet 12 is determined by the residence time and the cross-section of the first portion 12a and the second portion 12b. The second portion 12b is adjoined by a third portion 12c, which is also part of the outlet 12 and has a larger cross-sectional area than the second portion 12b.

[0097] The total length of the two portions 12a and 12b of the outlet 12 can be between 100 mm and 350 mm, in particular between 200 mm and 300 mm.

[0098] With reference to Figure 6 A system 100 comprising the aforementioned device 10 for carbonating a liquid is described. The device 10 is only schematically shown here. However, the system 100 can essentially be combined with all embodiments of the device 10 described here. For the sake of clarity, the flow direction of the liquid is indicated with a thick arrow and the flow direction of the gas with a thin arrow.

[0099] The system comprises a mixing unit 101, which is configured to degas the supplied water and to mix it with a concentrate, if necessary. Such a concentrate is used, for example, for the production of juice mixed beverages or soda and other soft drinks. From the mixing unit 101, the liquid is then fed to a liquid pump unit 102. The liquid pump unit 102 is configured to set a predetermined liquid feed pressure, through which the liquid is supplied to the inlet 11 of the device 10. As explained in more detail below, the liquid feed pressure is an important parameter for the carbonation of the liquid. The liquid at the liquid feed pressure is then supplied to the device 10 (syringe). Furthermore, the system 100 comprises a supply unit for the gas, wherein the gas, in particular CO2 in a gas feeder 103, can be brought to a predetermined gas feed pressure. The gas at the gas feed pressure is guided to the feeder 13 of the device 10. After the carbonation of the liquid in the device 10, it is fed to a buffer tank 105. In this case, the buffer tank is at a buffer pressure, which can be generated from the gas from the supply unit. Such a buffer pressure is necessary for the gas dissolved in the liquid not to escape again. The buffer pressure, in particular the difference to the liquid feed pressure, is also an important parameter in the carbonation process of the liquid.

[0100] For better illustration of the respective functions, the sensor 20 and the control device 30 are shown as separate blocks in the schematic drawing. However, both elements (or the sensor 20 and the control unit 30 each separately) can be configured as part of the device.

[0101] The sensor 20 receives the acoustic signals emitted from the device and generates a frequency spectrum (amplitude as a function of frequency) from these signals. This frequency spectrum (see below with reference to Fig. 2) is transmitted to the control unit 30. Figure 7 The frequency spectrum is transmitted to the control unit 30 as an example explanation.

[0102] The control unit 30 comprises e.g. a processor and a storage medium. For example, a reference frequency spectrum for the device, when the device is not operated in cavitation mode, can be stored on the storage medium. Furthermore, a database with products (liquid to be carbonated) and associated parameters (e.g. optimal gas feed pressure, liquid feed pressure, temperature and / or buffer pressure) can be stored on the storage unit. Thus, it is known that products with a high oxygen content tend to foam during the filling process and are therefore preferably carbonated at a high differential between the buffer pressure and the liquid feed pressure. Furthermore, the storage medium can comprise set values which can be set by the user, for example.

[0103] The control unit 30 receives data (frequency spectrum) from the sensor 20. From a comparison between the received frequency spectrum and the stored reference frequency spectrum, the control unit 30 determines whether the device 10 is operated in cavitation mode or in normal mode without cavitation. Based on this comparison, the control unit 30 determines which of the parameters liquid feed pressure, buffer pressure and / or gas feed pressure can need to be adjusted in order to operate in a certain mode or to reach a set value. Subsequently, the control unit 30 changes said parameters by corresponding parameter changes at the liquid pump unit 102, the buffer tank 105 and / or the gas feeder 103. It is also conceivable to change the temperature of the liquid to be carbonated, since a higher temperature favors the occurrence of cavitation due to the higher vapor pressure of the liquid to be carbonated.

[0104] The control device 30 can be configured to regulate the system 100 in the described manner. To this end, the control device 30 can be configured to continuously regulate the liquid feed pressure, the buffer pressure, the gas feed pressure and / or the temperature of the liquid to be carbonated, so that the device 10 is continuously operated in a certain mode or so that one or more of said parameters corresponds to a fixed set value.

[0105] The control unit 30 can also be configured to set the position of the displacement body 15. This can be achieved by the control unit 30 controlling its position within the device 10 by means of a drive (e.g. an electric, pneumatic or membrane-driven drive) of the displacement body 15. The position of the displacement body represents another parameter which is important for carbonation. In particular, if the displacement body 15 has a non-constant cross-section, the opening area of the annular gap 14 is also influenced by the displacement body position.

[0106] Although not shown in the figures, the control unit 30 can also receive data and / or signals from the liquid pump unit 102, the gas feeder 103 and / or the buffer tank 105. To this end, the components can be equipped with appropriate sensors, such as pressure sensors, and transmit the measured data to the control unit 30. In this respect, it should be mentioned that the described system can in principle also exist without the sensor 20. The control unit 30 can be configured to control the liquid pump unit 102, the gas feeder 103 and / or the buffer tank 105 in dependence on the transmitted sensor data, such that the liquid feed pressure, the gas feed pressure and / or the buffer pressure correspond to fixed set values.

[0107] Finally, the carbonated liquid is delivered from the buffer tank 105 to the filling device 104. The filling device 104 is configured to fill the carbonated liquid into a container.

[0108] Specific examples of suitable parameters in the beverage carbonation and filling process are given. The liquid feed pressure can be between 5 and 11 bar. The pressure difference between the buffer pressure and the liquid feed pressure (the liquid feed pressure is usually the greater pressure) can be chosen depending on the liquid to be carbonated. For liquids to be carbonated which are prone to foaming during carbonation and filling, carbonation at a pressure difference of more than 4 bar, in particular more than 6 bar. In this case, the adjustment of the pressure difference is achieved in particular by adjusting the liquid feed pressure. Liquids to be carbonated which have a low tendency to foam can be filled at a pressure difference of 3 bar or less.

[0109] Finally, Figure 7 An exemplary schematic spectrum received with the acoustic signal sensor is shown. Here, a direct comparison of the spectrum when the device is operated in cavitation mode and when the device is operated in normal mode without cavitation is shown. In this case, the spectrum of the normal mode can be used as a reference spectrum, for example received under predetermined conditions, and can be used as a basis for comparison for further measurements. The abscissa shows the frequency in Hertz, the ordinate shows the relative amplitude (relative to a fixed reference value in decibels). Since this is a schematic representation of the spectrum, no specific values are given on the axes. At high frequencies, there is a significant difference in the amplitude of the acoustic signal. In this frequency range, for example in the range between 10 Hz and 100 kHz, in particular between 100 Hz and 10 kHz, the acoustic signal has a higher amplitude when the device is operated in cavitation mode. This essential difference can be identified by the control unit in the described comparison. Thus, the control unit will detect that the device is operated in cavitation mode.

Claims

1. A device (10) for carbonating a liquid, characterized in that, The device comprises an inlet (11) for a liquid to be carbonated, a feeder (13) for a gas, in particular CO2, wherein the gas is used for carbonating the liquid, and an outlet (12) for discharging a carbonated liquid, which is a mixture of liquid and gas, wherein an annular gap (14) is arranged between the inlet (11) and the outlet (12), and wherein the device (10) further comprises a displacement body (15) which is axially movable in the flow direction of the liquid, such that the opening area of the annular gap (14) through which the liquid passes can be changed when the displacement body (15) is moved.

2. The device (10) according to claim 1, characterized in that The feeder (13) is located downstream of the annular gap (14).

3. The apparatus (10) according to claim 1, characterized in that The device further comprises a gas channel (13b), and a gas metering device (13c), wherein the gas channel (13b) is arranged outside the outlet (12), and wherein the gas metering device (13c) is configured to adjust or control the amount of gas flowing from the gas channel (13b) into the liquid to be carbonated by changing the opening between the gas channel (13b) and the outlet (12).

4. The apparatus (10) according to claim 1, characterized in that The displacement body (15) has a cross section which tapers in the flow direction, or wherein the displacement body (15) has a cross section which widens in the flow direction.

5. The apparatus (10) according to claim 1, characterized in that The displacement body (15) has one or more recesses (15a) on its upstream side.

6. The apparatus (10) according to claim 1, characterized in that The inlet (11) and the outlet (12) are angled between 80° and 100° to each other, and wherein the displacement body (15) is movable in the flow direction within the outlet (12).

7. The device (10) according to claim 1, characterized in that The diameter of the outlet (12) monotonously increases at least in a portion downstream.

8. The device (10) according to claim 7, characterized in that The outlet (12) is of annular configuration, wherein the outlet (12) comprises a first portion (12a) downstream of the annular gap (14) and a second portion (12b) adjacent to the first portion (12a) downstream, and wherein the second portion (12b) has a larger cross section than the first portion (12a).

9. The device (10) according to claim 8, characterized in that The device further comprises a liquid outlet (16) which optionally has a circular cross section, wherein the liquid outlet (16) is arranged downstream adjacent to the second portion (12b) of the outlet, and wherein the cross section of the liquid outlet (16) is larger than the cross section of the second portion (12b).

10. The device (10) according to claim 1, characterized in that The device further comprises a sensor (20) for receiving an acoustic signal generated by the device, wherein the sensor (20) is arranged outside the outlet (12) or inside the outlet (12), and wherein the sensor (20) is configured to receive or generate a frequency spectrum of the acoustic signal.

11. The device (10) according to claim 10, characterized in that The device further comprises a control unit (30) which is configured to compare the frequency spectrum received by the sensor (20) with a predetermined reference frequency spectrum, and determine from the comparison whether the device (10) is operated in a cavitation state or not.

12. The apparatus (10) according to claim 11, characterized in that The control unit (30) is also configured to perform a regulation of the apparatus (10) based on a comparison between the received spectrum and the predetermined reference spectrum, so as to control and / or regulate at least one of the following parameters: - the temperature of the liquid to be carbonated; - the gas pressure in the feeder (13); - the pressure of the liquid to be carbonated in the inlet (11); and - the opening area of the annular gap (14).

13. A system (100) for carbonating a liquid, characterized in that, The system comprises: - the apparatus (10) according to claim 1, - a mixing unit (101) configured to degas the supplied water and mix the degassed water with a concentrate to produce the liquid to be carbonated, - a liquid pump unit (102) for delivering the liquid to be carbonated to the apparatus (10) at an adjustable liquid feed pressure, - a gas feeder (103) for delivering gas to the apparatus (10) at an adjustable liquid feed pressure, and / or - a filling device (104) configured to fill the carbonated liquid into containers.

14. The system (100) according to claim 13, characterized by The system comprises: - the apparatus (10) according to claim 12, and - a buffer tank (105) for storing the carbonated liquid at an adjustable buffer pressure, wherein the control unit (30) is also configured to control and / or regulate the difference between the feed pressure and the buffer pressure.

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