Device and method for continuous gas exchange in a stream of a fluid mixture

Abstract

Device for continuous gas exchange in a stream of a fluid mixture, - with a nozzle (2, 26) for supplying a fluid mixture composed of several components into a volume (11) filled with the fluid mixture during use of the device, which nozzle (2, 26) has a conical annular gap (8, 27) arranged between a conical inner surface of a nozzle jacket (5, 30) and a guide cone (7, 28), opening at its tip into the volume (11) at a nozzle opening (10, 31) and a fluid supply (6, 29) opening tangentially into the conical annular gap (8, 27), - with a separator (3, 33) for separating a first gas contained in the fluid mixture, which has a separation section (18, 34) arranged in the volume (11) and flow-connected to an outlet (20, 41) with an inlet opening (19) arranged concentrically to the nozzle opening (10, 31) and axially spaced from it, - and with at least one gas supply (4, 37) flow-connected to a gas source for a second gas to be dispersed into the fluid mixture, which is spaced apart from the nozzle opening (10, 31) at the level of the separation section (18, 34) and radially outside of it at an outlet (21, 38) into the volume (11).

Description

[0001] The invention relates to a device for continuous gas exchange in a flow of a fluid mixture. The invention further relates to a corresponding method.

[0002] Many biological, food-processing, or medical applications require the exchange of gases contained in liquids. For example, in certain microbiological processes, microorganisms suspended in a liquid metabolize a gas dissolved in the liquid and secrete another gas into the liquid as a metabolic product. Above a certain concentration, the secreted gases often have an inhibitory or even toxic effect on the organisms, making separation of these gases essential. At the same time, it is necessary to ensure a continuous supply of the gas required for metabolism. Examples of such biological processes include the cultivation of micro- and macroalgae, aerobic bacteria, or inoculation cultures. Gas exchange is also important, for example, for the water in aquariums and fish farms.The organisms there require oxygen, which they consume in dissolved form, and at the same time release CO2.

[0003] The two process steps of separating a first gas from a liquid and dispersing a second gas into the same liquid are currently usually carried out in separate devices, through which the liquid medium to be treated passes one after the other. However, such a procedure is usually associated with very high equipment complexity and correspondingly high costs, as well as considerable space requirements, and is also accompanied by significant process and process control engineering effort.

[0004] Separation systems are known in which mixtures of substances are broken down into their components by creating a strong flow vortex. For example, DE 36 15 747 A1 describes a cyclone separator comprising two conical dip tubes with a tangential fluid inlet. Separators with cylindrical dip tubes are known from DE 195 02 202 A1 and DE 25 38 664 A1.

[0005] The subject of DE 34 27 395 A1 is a cyclone separator with a telescopically extendable immersion tube. The separator is equipped with a separation chamber that has several outlets for separated solid particles and an inlet for pressurized water. However, the introduction of an additional gas, for example, via the aforementioned outlets, is not provided for according to the teaching of this document.

[0006] In addition to devices that can only degas or introduce gas, which must therefore be combined, membrane processes are used that are capable of inducing an exchange of dissolved gases in a liquid medium. Devices for gas exchange in liquids that use membranes are known, for example, from EP 1 988 984 B1 and the publications cited therein.

[0007] The disadvantage of using membrane processes for gas exchange, however, is that the membranes become clogged or worn over time, which is why certain liquid media, such as suspensions, cannot be treated at all and / or the membranes must be replaced at regular intervals. Furthermore, at high gas throughputs, they require a large exchange surface, which requires a corresponding amount of space, and / or the membrane is exposed to a high pressure difference during operation, which places considerable stress on the pore structure and thus leads to rapid wear.

[0008] The invention is therefore based on the object of creating a possibility for continuous gas exchange in liquid media, which can be implemented using simple means, requires little maintenance in operation and is suitable for a large number of different liquid media.

[0009] The object is achieved by a device having the features of patent claim 1 and by a method having the features of claim 10.

[0010] Advantageous embodiments of the invention are specified in the subclaims.

[0011] A device according to the invention comprises a nozzle for supplying a fluid mixture into a volume filled with the fluid mixture when the device is in use, a separator arranged in the volume and a gas supply opening into the volume for a second gas to be dispersed into the fluid mixture simultaneously with the separation of the first gas.

[0012] A "fluid mixture" or "liquid medium" is understood here to mean a medium comprising at least one liquid and at least one first gas contained therein. Other substances, such as solid particles or other dissolved gases, may also be present in the fluid mixture. The first gas before treatment and / or the second gas after treatment may be homogeneously or inhomogeneously distributed in the fluid mixture, i.e., in particular, dissolved or present as a dispersion in the form of finely distributed gas bubbles in the liquid.

[0013] The nozzle has a conical annular gap arranged between a conical inner surface of a nozzle shell and a guide cone, opening into the volume at its tip via a nozzle opening. The nozzle is equipped with a fluid supply that opens tangentially into the conical annular gap, but axially spaced from the nozzle opening. The tangential entry into the annular gap forces the fluid mixture into a rotating motion, the angular velocity of which increases dramatically towards the nozzle opening. Due to the high rotational speed, the fluid mixture is ejected into the volume at the nozzle opening as a strongly swirled fluid jet. In particular, the rotational speed is higher than with an otherwise equally sized hollow-conical nozzle body due to the fluid mixture being guided through an annular gap.

[0014] The width of the conical annular gap, i.e., the distance between the inner wall of the nozzle shell and the outer wall of the guide cone, should at no point be larger than the inner diameter of the fluid supply at its junction with the annular gap. The annular gap can have an acute or obtuse opening angle. For example, the opening angle is between 30° and 180°, preferably between 45° and 170°, and particularly preferably between 60° and 135°; however, the conical boundary surfaces of the annular gap do not necessarily have to have straight surface lines.The radial distance between the conical inner surface of the nozzle shell and the outer surface of the guide cone is constant between the fluid inlet and the tip of the guide cone, or decreases continuously toward the nozzle opening. The invention does not provide for an expansion of the distance between the boundary surfaces of the annular gap between the fluid inlet and the nozzle opening, for example, to form a mixing chamber. Therefore, the volume available to the fluid mixture in the annular gap decreases continuously up to the nozzle opening, which continuously increases the axial velocity, as well as the rotational speed.

[0015] In the highly swirled fluid jet forming in the volume downstream of the nozzle opening, a strong pressure gradient exists in the radial direction, with the pressure in a region near the axis being much lower than at the edge of the fluid jet. As a result, gases contained in the fluid mixture in the form of small gas bubbles concentrate in the center of the fluid jet, while the fluid mixture in its outer region is at least largely free of these gases. If the fluid mixture is a liquid with at least one gas dissolved in it, the pressure inside the fluid jet can become so low that at least one gas outgasses, which subsequently accumulates in the center of the fluid jet.

[0016] The separator's separation section is immersed in the fluid jet forming in the volume downstream of the nozzle opening. The separation section is designed to separate a portion of the fluid mixture located radially inward in the fluid jet from the remaining fluid mixture and discharge it via an outlet branching off the separation section. Since, as mentioned, gaseous components of the fluid mixture concentrate in the region near the axis of the strongly swirled fluid jet, the discharged portion of the fluid mixture consists of gas or a liquid heavily enriched with gaseous components. The separation section, which is preferably arranged radially symmetrically to the axis of the conical annular gap, is preferably in the shape of a tubular cylinder, but can have additional elements that promote the separation of the first gas, such as a funnel-shaped inlet opening or an outer shell that widens conically in the direction away from the nozzle opening.

[0017] The gas supply for the second gas to be dispersed into the liquid medium opens at the level of the separation section and radially outward from it in the volume. This ensures that the flow of the second gas is only added to the fluid mixture once the first gas has already been separated. Due to the still very strong rotational movement of the fluid jet radially outward at the separation section of the separator, a rapid and intensive mixing of the second gas into the fluid mixture occurs, which may also promote the dissolution of the second gas if the gas is soluble in the liquid.

[0018] The flow of the fluid mixture to be treated is fed to the nozzle under high pressure, i.e. the fluid mixture is usually already at a corresponding pressure upstream of the nozzle, or it is brought to a corresponding pressure by means of a pump arranged in the fluid supply, upstream of the nozzle. Such a pump has the advantage that it leads to a defined pressure at the inlet to the annular gap; its pumping capacity can also be variable and controllable depending on measured parameters. For this purpose, the device according to the invention is preferably equipped with, for example, an electronic control unit, which can also perform other control tasks within the scope of the invention.

[0019] The volume is preferably a preferably closed container filled with the fluid mixture or a liquid-conducting conduit; however, it can also be an open container, a basin, or a body of water. In the case of a liquid-conducting conduit, such as a pipeline through which the fluid mixture flows, the nozzle and separating section are preferably arranged concentrically to the pipe axis. The device according to the invention can, in particular, be easily installed in an existing pipeline and enables continuous treatment of the fluid mixture conveyed through the pipeline.

[0020] A particularly advantageous embodiment of the invention provides that a phase separator, for example a gas phase separator, is integrated into the outlet of the separator and is fluidly connected to the fluid supply via a return line. In the phase separator, the first gas contained in the fluid mixture received at the separating device is separated from the remaining fluid mixture received at the separating device. The liquid phase of the fluid mixture, freed from the first gas, is then returned via the return line to the fluid supply of the nozzle. The liquid phase can be returned by means of a pump integrated in the return line; an embodiment of the invention is also possible in which the return line opens upstream of a pump arranged in the fluid supply; in this case, no separate pump is required in the return line.

[0021] In a further embodiment of the device according to the invention, various adjustment options are provided to adapt the separator's separation efficiency to the respective requirements. These include, in particular, means for varying the axial distance between the nozzle opening and the separator's inlet opening and / or the axial distance of the inlet of the gas supply for the second gas from the nozzle opening and / or the axial position of the nozzle's guide cone relative to the conical inner surface of the nozzle shell.

[0022] A similarly advantageous embodiment of the invention provides for a supply line to open into the fluid supply, through which an additional gas can be introduced into the fluid mixture. Due to the partial pressure of this component, the additional gas can be used as a "sparging gas" to assist the degassing of the first gas in the fluid jet. Furthermore, the additionally introduced gas reduces the viscosity of the fluid mixture and thus increases the rotational speed of the fluid mixture at the nozzle opening and thus the volume of the fluid jet. In particular, a partial flow of the second gas can also be used in this way as a sparging gas for the first gas.

[0023] In a similarly advantageous variant of the invention, the nozzle is equipped with a demixing chamber arranged upstream of the nozzle opening. The demixing chamber is a cylindrical chamber arranged axially symmetrically to the conical annular gap upstream of the nozzle opening, i.e., downstream of it in the flow direction of the fluid mixture. It has openings arranged on its end faces. The length of these openings corresponds, for example, to 0.5 to 2 times the length of the guide cone, and the inlet opening on the guide cone side is larger than the outlet opening opposite it. In this case, the separator is arranged downstream of and spaced from the outlet opening of the demixing chamber.

[0024] A heating device is expediently provided in the fluid supply and / or in the nozzle jacket and / or in the guide cone. Heating the fluid mixture before and / or during its passage through the nozzle reduces its viscosity, which in particular increases the rotational speed of the fluid jet and thus further reduces the pressure in the center of the fluid jet. In general, the higher temperature reduces the solubility of gases dissolved in the fluid, thus promoting outgassing.

[0025] To assist in separating the first gas from the fluid mixture, the device is preferably equipped with an ultrasonic device. The ultrasonic device can be designed such that the guide cone and / or the nozzle as a whole and / or the separator and / or a line and / or a container in which the device is arranged is / are subjected to rapid, ultrasound-generating vibrations. During the vibration, zones of varying pressure form in the fluid mixture, which promote the development of cavitation, in which the first gas dissolved in the fluid mixture is released in the form of fine gas bubbles. The gas bubbles coagulate and collect as the gas phase in the center of the rotating fluid jet and can then be removed from the fluid mixture by means of the separator.

[0026] Another advantageous embodiment of the device according to the invention provides for a central outlet through the guide cone. A partial flow of the fluid mixture can be drawn off from the rotating fluid jet forming in front of the nozzle opening via the outlet, for example by means of a pump, thereby supporting the separator arranged downstream of the nozzle opening.

[0027] Furthermore, the user of the device according to the invention has access to a multitude of parameters that can be adjusted according to the task at hand. These include, in particular, the cross-sectional area of ​​the nozzle opening, the position of the guide cone in the nozzle, the pressure in the fluid line, the distance between the nozzle opening and the separator in volume, the cross-sectional area of ​​an inlet opening on the separator, the shape of the separator, the cross-sectional area of ​​the nozzle opening, the position of the guide cone in the nozzle, the pressure in the fluid supply, the distance between the inlet of the gas supply line and the nozzle outlet, the geometric conditions of the gas supply line, the flow rate of the second gas metered into the gas supply line, and / or the flow rate of a sparging gas supplied. Such parameters can be adjusted entirely or partially manually or automatically using the aforementioned control unit.

[0028] The object of the invention is also achieved by a method having the features of patent claim 10.

[0029] In the method according to the invention, the separation of the fluid mixture takes place as follows: A fluid mixture composed of at least a liquid and at least one first gas contained therein is fed to a nozzle via a fluid feed line, for example using a pump. The first gas, or gases, can be wholly or partially dissolved in the liquid and / or dispersed therein in the form of small gas bubbles. The nozzle has a conical annular gap, i.e. a volume delimited by two conical surfaces, wherein the fluid mixture is fed into the conical annular gap via a fluid feed opening tangentially into the annular gap. The fluid mixture is forced into a spiral-narrowing path in the conical annular gap and ejected from a nozzle opening arranged at the tip of the conical annular gap in the form of a swirling fluid jet into a volume filled with the same fluid mixture.The pressure of the fluid mixture in the volume is lower than the pressure of the supplied fluid mixture, for example it is between 0.01 bar and 1.5 bar, with a pressure in the fluid supply of, for example, between 2 bar and 20 bar, preferably between 2 bar and 5 bar (data in each case above ambient pressure). In the swirling fluid jet, a pressure gradient forms in the radial direction, which ensures that components of low density, in particular gaseous components, accumulate in the center of the swirling fluid jet. The strength of the pressure gradient depends in particular on the pressure difference between the pressure of the supplied fluid mixture and the pressure in the volume. If the first gas is dissolved in the fluid mixture, the pressure in the fluid supply line is preferably selected such that the first gas outgasses from the fluid mixture and concentrates in the center of the fluid jet.With the help of a separator, a partial flow of the fluid mixture (here referred to as the "separation flow") is withdrawn from the zone of reduced pressure at the center of the swirling fluid jet and separated from the remaining fluid mixture. The dynamic pressure of the fluid mixture in the swirling fluid jet is usually sufficient to remove the separation flow from the volume; however, the separator can optionally be equipped with means for applying a vacuum, such as a pump or a piping system in which the weight of the withdrawn fluid is used to generate a vacuum.

[0030] Simultaneously with the at least partial separation of the first gas or gases from the fluid mixture, a second gas or several second gases are introduced into the fluid mixture. This is achieved according to the invention by introducing the second gas or gases into the swirling jet of the fluid mixture emerging from the nozzle. To prevent part of the second gas from being separated together with the first gas at the separator, the second gas is preferably only introduced at the level of or downstream of the inlet opening of the separator, as seen in the flow direction of the fluid jet emerging from the nozzle. In this case, the second gas or gases mix intimately with the fluid mixture. Here, too, the term "mixing" is to be understood generally and can encompass a dispersion of gas bubbles in the fluid mixture as well as an at least partial dissolution of the gas.

[0031] In an advantageous embodiment of the method according to the invention, a sparging gas is supplied to the fluid mixture upstream of the nozzle opening to separate the first gas from the fluid mixture. The supply can take place inside the nozzle or upstream of the nozzle. The sparging gas assists in the separation of the first gas from the fluid mixture. For example, nitrogen can be used as a sparging gas to remove oxygen from the fluid mixture.

[0032] An inert gas and / or the second gas are preferably used as the sparging gas. In the latter case, for example, a stream of the second gas originating from a common source is split into two partial streams, one of which is fed to the gas supply, while the other is introduced upstream of the nozzle opening as a sparging gas into the fluid supply for the fluid mixture.

[0033] If the sparging gas is taken from a source where it is cryogenic or compressed, it can be advantageously used for cooling by extracting its evaporation or expansion enthalpy from the already separated first gas. In this way, for example, substances contained in the first gas can be separated through cryogenic condensation. For example, in winemaking, this can prevent the loss of important volatile aromatic compounds during the degassing of the wine. The substances separated from the first gas can be added back to the fluid mixture—in this example, the degassed wine—in a subsequent step.

[0034] A preferred embodiment of the invention provides that the nozzle and the separator are integrated into a partial circuit for the fluid mixture. After passing through the separator, the separation stream is fed to a phase separator and in turn subjected to a separation in which the first gas or gases are separated from the remaining fluid mixture, unless complete separation has already taken place in the separator. The remaining fluid mixture, largely freed of the first gas or gases, is then returned via a return line to the feed line of the nozzle. A conveying device, for example an electric pump, can be arranged in the return line, by means of which fluid mixture can be continuously fed from the separator into the fluid supply upstream of the nozzle.

[0035] The device and method according to the invention enable continuous gas exchange, i.e., a first gas contained in the fluid mixture is removed and a second gas is fed into the fluid mixture at the same time. They are particularly suitable for treating homogeneous or inhomogeneous fluid mixtures, such as solutions or suspensions, and can also be used with heat-sensitive fluid mixtures. For example, they are suitable for the biological, food-processing, or medical applications mentioned above. The liquid contained in the fluid mixture is, for example, water, an aqueous solution or suspension from a microbiological or food-processing process, or oil. For example, it is wine or another beverage. For example, it is water that needs to be degassed with regard to its oxygen content and carbonated at the same time.The invention is of course not limited to these examples, but can be used in a variety of other applications.

[0036] Compared to prior art methods and devices, the invention requires comparatively low energy consumption, requires no additional substances to carry out the separation, and is gentle on the fluid mixture being treated and the material used. The device according to the invention does not require filters, membranes, moving parts, or other wear parts and operates quietly during operation.

[0037] Embodiments of the invention will be explained in more detail with reference to the drawings. The schematic views show: Fig. 1: A device according to the invention in a first embodiment in longitudinal section, Fig. 2: The device from Fig. 1 in cross section along the section line BB in Fig. 1, Fig. 3 A device according to the invention in another embodiment in longitudinal section.

[0038] The Fig. 1 and Fig. The device 1 shown in Figure 2 serves to treat a fluid mixture containing a liquid and a first gas. During the treatment, the first gas is continuously removed at least partially from the fluid mixture, and a second gas is simultaneously dispersed into the fluid mixture. For example, the liquid in the fluid mixture is water or an aqueous solution, the first gas is a gas dissolved in the liquid, and the second gas is a gas to be dissolved in the liquid.

[0039] The device 1 comprises a nozzle 2 for introducing the fluid mixture, a separator 3 arranged axially spaced in front of the nozzle for removing the first gas and a gas supply 4 for introducing the second gas.

[0040] The nozzle 2 comprises a nozzle casing 5 with a conical inner surface, into which a fluid supply 6 opens tangentially. Within the nozzle casing 5, a likewise conically shaped guide cone 7 is arranged such that a conical annular gap 8 is open between the inner wall of the nozzle casing 5 and the outer wall of the guide cone 7, and preferably such that the conical tip 9 of the guide cone 7 is substantially aligned with a nozzle opening 10 of the nozzle 2. The flow cross-sections of the nozzle opening 10, the annular gap 8, and the fluid supply 6 are preferably selected to be substantially equal.The inner surface of the conical nozzle jacket 5 and the outer surface of the guide cone 7 can have the same opening angle, but it is also conceivable that the opening angle of the outer surface of the guide cone 7 is more acute than the opening angle of the inner surface of the nozzle jacket 5, i.e. the radial distance between the nozzle jacket 5 and the guide cone 7 is reduced in the direction of the nozzle opening 10, as in . Fig. 1 shown.

[0041] Nozzle 2, separator 3 and gas supply line 4 are accommodated within a volume 11, which is, for example, a container or a line and is filled with the fluid mixture to be treated.

[0042] The guide cone 7 can be fixedly mounted within the nozzle casing 5 or - as shown here - can be accommodated in an axially movable manner by means of a manual or motor-driven displacement device 12 in order to adapt the device 1 to the properties of the fluid mixture to be treated and / or the respective work task.

[0043] During operation of the nozzle 2, a fluid mixture to be treated, for example a liquid to be degassed, is introduced into the annular gap 8 at a pressure of, for example, 2-5 bar via the fluid supply 6 in the direction of the arrow. In the annular gap 8, the fluid mixture is set into a rapid rotational movement, the angular velocity of which increases due to the radius of the annular gap 8 decreasing in the flow direction up to the nozzle opening 10. For the same reason, the linear velocity component directed towards the nozzle opening 10 also increases. The fluid mixture leaves the nozzle 2 at the nozzle opening 10 and is introduced into the volume 11, in which a pressure of, for example, 1 bar prevails, as a strongly swirled fluid jet 13 with high torque and high axial velocity in the direction of the arrow 14.Due to the high rotation speed, a zone 16 of greatly reduced pressure is created along a central axis 15 of the fluid jet 13, which is also the axis of symmetry of the annular gap 7. In the zone 16, dissolved gas contained in the fluid mixture, for example outgassing, collects in the form of a large number of small gas bubbles or a single gas bubble and in this way separates at least partially from the liquid contained in the fluid mixture.

[0044] The separator 3 with a separating section 18 is immersed in zone 16. The separating section 18 is in the Fig. 1 and Fig. The embodiment shown in Figure 2 is a tubular cylinder arranged radially symmetrically to the axis 15 in the volume 11, and whose front inlet opening 19 is axially spaced from the nozzle opening 8. In the exemplary embodiment, the cross-sectional area of ​​the inlet opening 19 is larger than that of the nozzle opening 10, but it can also be selected to be the same size or smaller. The separating section 18 is fluidly connected to an outlet 20, via which the fluid mixture penetrating the separating section 18 is withdrawn from the volume 11, optionally by means of a pump (not shown here); however, a pump is not absolutely necessary for this purpose.

[0045] At a greater radial distance from the axis 15 and radially outside the separation section 18, there is thus a fluid mixture that is essentially free of components of the first gas. A second gas is introduced into this fluid mixture by means of the gas supply 4. The second gas is supplied from a source not shown here, for example a tank, and enters the fluid mixture located in the volume 11 at an outlet 21 of the gas supply 4. To prevent the second gas from reaching the low-pressure zone 16 and being removed from the fluid mixture together with the first gas, the outlet 21 is located at the level of the separation section 18 and radially spaced from it. The gas emerging at the outlet 21 thus reaches the outer region of the swirled fluid jet 13 and is there intensively mixed with the surrounding fluid mixture. To further increase the efficiency of the gas introduction, the gas supply 4 can, as in Fig. 1, in the area of ​​the outlet 21 it can be nozzle-shaped, i.e. with a conically tapered cross-section.

[0046] Furthermore, the device 1 can be arranged horizontally or vertically in the volume 11; in particular, a vertical arrangement in a gas phase separator (in Fig. 1 not shown), the separated gas can escape upwards, while the liquid phase remaining in the gas phase separator can be returned to the fluid supply 5. If the second gas was stored in the source in a cryogenically liquefied state or under pressure, the energy required to evaporate or expand the second gas can be extracted from other fluid streams, for example, the first gas discharged via the outlet 20, by means of a heat exchanger not shown here.

[0047] To assist in removing the first gas from the fluid mixture, a sparging gas can be introduced into the fluid mixture supplied to the nozzle 2 via a gas supply line 22 leading into the fluid supply line. The sparging gas is, in particular, a partial flow of the second gas, the remaining flow of which is introduced into the fluid mixture via the gas supply line 4. Instead of the second gas, however, another gas, in particular an inert gas, for example, nitrogen or a noble gas, can also be used as the sparging gas.

[0048] Fig. 3 shows a device 25 according to the invention in another embodiment.

[0049] In a similar manner to the device 1, the device shown in Fig.The device 25 shown in Figure 3 has a nozzle 26 with a conical annular gap 27, which is arranged between an axially movable guide cone 28 and a conical nozzle shell 30 and into which a fluid supply 29 opens. A nozzle opening 31 is provided at the tip of the conical annular gap 27.

[0050] Just like the device 1, the device 25 has a separator 33 with a tubular cylindrical separating section 34, which is arranged axially spaced along an axis 36 in front of the nozzle 27 and whose end face opposite the nozzle 27 has an inlet opening 35, as well as a gas supply line 37, which opens laterally to the separating section 34 with an outlet 38.

[0051] Furthermore, the device 25 can be equipped with an ultrasonic generator 39, by means of which, for example, the guide cone 28 can be set into very high-frequency vibrations (ultrasonic vibrations). This generates cavitations downstream of the nozzle opening 31 in the fluid mixture to be treated, into which dissolved first gas from the fluid mixture can outgas. This further increases the efficiency of the device 25. Furthermore, instead of the guide cone 28, the entire nozzle 25 or the nozzle jacket surrounding the guide cone 28 can also be set into ultrasonic vibrations.

[0052] The device 25 also has a phase separator 40, in which the fluid mixture, which is separated in the separator 33 and fed to the phase separator 40 via an outlet line 41 and is heavily enriched with the first gas, is separated into a gas phase and a liquid phase. While the gas phase is discharged via a gas discharge line 42, the liquid phase, freed from the gas, is fed back into the fluid feed 29 via a return line 43, upstream of a pump 44 that conveys the untreated fluid mixture to the nozzle 26. A heating element 45, for example an electric heater, is additionally arranged in the fluid feed 29 in the device 25, by means of which the fluid mixture can be heated and thus its viscosity reduced. Furthermore, a tubular demixing chamber 46 can be arranged downstream of the nozzle opening 31, which promotes the separation of the fluid mixture emerging from the nozzle 26.The length and cross-section of the demixing chamber 46 are selected so that a good separation effect is achieved for the respective fluid mixture.

[0053] To assist in separating the first gas from the liquid, a sparging gas, such as nitrogen or another inert gas, can also be used in the device 25. For this purpose, the device 25 has a gas supply line 47 opening into the fluid supply line 29 downstream of the pump 44, as well as a mixing element 48 installed in the fluid supply line 29 downstream of the opening of the gas supply line 47. The mixing element 48 serves to intensively mix the sparging gas introduced via the gas supply line 47 with the surrounding fluid mixture supplied via the fluid supply line 29.

[0054] The operation of the device 25 is similar to that of the device 1. A fluid mixture, for example water, in which a first gas, for example oxygen, is present in dissolved or mixed form, is transported via the fluid supply line 29 by means of the pump 44 to the nozzle and is enriched with a sparging gas supplied via the gas supply line 45. The fluid mixture is set into a rapid rotational movement in the annular gap 27 of the nozzle 26 and leaves the nozzle opening 31 in the form of a strongly swirled fluid jet, displacing the fluid mixture already present in the volume 11. In the swirled fluid jet, a strong pressure gradient in the radial direction ensures that components of the first gas and the sparging gas dissolved or mixed in the fluid mixture accumulate in a gas-rich phase in the center of the steel along the axis 36.The low partial pressure of the first gas in gas bubbles of the sparging gas promotes the outgassing of the first gas from the surrounding liquid of the fluid mixture. The central gas-rich phase is separated in separator 33 from the surrounding phase of the fluid mixture, which has been largely freed of the first gas. In phase separator 40, the separated gas-rich phase is further separated into a gas phase and a liquid phase. While the gas phase is discharged via gas discharge line 42, the separated liquid is fed back into the fluid supply line 29 via return line 43. Simultaneously with the removal of the first gas, a second gas, for example, carbon dioxide, is introduced via gas supply line 37 into a region in volume 11 in which the fluid mixture has already been largely freed of the first gas, for example, into a region radially outside the separation section 34.Due to the continued strong swirling flow of the fluid mixture, the second gas is intimately mixed with the fluid mixture.

[0055] Alternatively or in addition to a separator 34 arranged in front of the outlet opening 31 of the nozzle 26 in the volume 11, the gas-rich phase in the center of the volume 11 in front of the outlet opening 31 of the nozzle 26 can also be withdrawn via an outlet 49 guided centrally through the guide cone 28, for example by means of a pump not shown here, and in this way separated from the remaining fluid mixture.

[0056] The invention is not limited to the exemplary embodiments shown here. Rather, various features of the devices 1, 25 can be combined with one another as desired, or the devices 1, 25 can be supplemented with further features. For example, a heating device or an ultrasound generator can also be provided in the device 1. Likewise, various operating parameters of a device according to the invention, such as the heating power of the heating element 30, the width of the annular gap 7, 27, the axial distance of the separator 3, 33 or the outlet 21, 38 from the nozzle 2, 26, or the pressure of a pump conveying the fluid mixture to be treated to the nozzle 2, 26, can be regulated by means of an electronic control system (not shown here) as a function of continuously measured parameters, such as the concentration of the first and / or second gas in the treated fluid mixture downstream of the separator 3, 33 and the gas supply 21, 37. List of reference symbols 1 device 2 nozzles 3 Separator 4 Gas supply line 5 Nozzle casing 6 Fluid supply 7 guide cones 8 Annular gap 9 Cone tip 10 nozzle opening 11 volumes 12 Shifting device 13 Fluid jet 14 Arrow 15 Axis 16 zones 17 - 18 Separation section 19 Inlet opening 20 Discharge 21 outlet 22 Gas supply line 23 - 24 - 25 Device 26 nozzle 27 Annular gap 28 guide cones 29 Fluid supply 30 nozzle casing 31 Nozzle opening 32 - 33 Separator 34 Separation section 35 Inlet opening 36 Axis 37 Gas supply line 38 Estuary 39 ultrasound generators 40 phase separators 41 Discharge 42 Gas discharge 43 Return line 44 Pump 45 Heating element 46 Separation chamber 47 Gas supply line 48 Mixing element 49 Excretion

Claims

[1] Device for continuous gas exchange in a flow of a fluid mixture, - with a nozzle (2, 26) for supplying a fluid mixture composed of several components into a volume (11) filled with the fluid mixture when the device is in use, which nozzle (2, 26) has a conical annular gap (8, 27) arranged between a conical inner surface of a nozzle casing (5, 30) and a guide cone (7, 28), which opens into the volume (11) at its tip at a nozzle opening (10, 31), and a fluid supply (6, 29) opening tangentially into the conical annular gap (8, 27), - with a separator (3, 33) for separating a first gas contained in the fluid mixture, which has a separating section (18, 34) arranged in the volume (11) and fluidly connected to an outlet (20, 41) with an inlet opening (19) arranged concentrically to the nozzle opening (10, 31) and axially spaced therefrom, - and with at least one gas supply (4, 37) which is fluidly connected to a gas source for a second gas to be dispersed in the fluid mixture and which opens into the volume (11) at an outlet (21, 38) at a distance from the nozzle opening (10, 31) at the level of the separating section (18, 34) and radially outside thereof. [2] Device according to claim 1, characterized by that a container filled with the fluid mixture or a line carrying the fluid mixture is provided as the volume (11). [3] Device according to claim 1 or 2, characterized by that a phase separator (40) is integrated in the outlet (20, 41) of the separator (3, 33), which is fluidly connected to the fluid supply (6, 29) via a return line (43). [4] Device according to one of the preceding claims, characterized bythat the axial distance between the nozzle opening (10, 31) and the inlet opening (19, 35) of the separator (3, 33) and / or the axial distance between the nozzle opening (10, 31) and the outlet (21, 38) of the gas supply (4, 37) for the second gas and / or the axial position of the guide cone (7, 28) of the nozzle (2, 26) relative to the conical inner surface of the nozzle casing (5, 30) is adjustable. [5] Device according to one of the preceding claims, characterized by that a gas supply line (22, 47) for a sparging gas opens into the fluid supply (6, 29) and / or into the annular gap (8, 27). [6] Device according to one of the preceding claims, characterized by that the nozzle (2, 26), downstream of the nozzle opening (10, 31), is equipped with a demixing chamber (46). [7] Device according to one of the preceding claims, characterized bythat a heating device (30) is provided in the fluid supply (6, 29), in the nozzle casing (5, 30) and / or in the guide cone (7, 28). [8] Device according to one of the preceding claims, characterized by an ultrasonic generator (39) for generating short-term, local pressure differences in the fluid mixture. [9] Device according to one of the preceding claims, characterized by that a further outlet (49) is provided centrally through the guide cone (7, 28) for discharging a partial flow of the fluid mixture present downstream of the nozzle opening (10, 31). [10] A method for continuous gas exchange in a flow of a fluid mixture, in which a fluid mixture containing at least one liquid and at least one first gas is fed to a nozzle (2, 26) which has a conical annular gap (8, 27), wherein the fluid mixture is fed into the conical annular gap (8, 27) via a fluid feed (6, 29) opening tangentially into the annular gap (8, 27), b. the fluid mixture in the conical annular gap (8, 27) is forced into a spirally narrowing path and is ejected into a volume (11) at a nozzle opening (10, 31) arranged at the tip of the conical annular gap (8, 27) in the form of a swirled fluid jet (13), wherein a zone (16) of reduced pressure is formed in the swirled fluid jet and the first gas contained in the fluid mixture is enriched in the zone (16) of reduced pressure, c. with the aid of a separator (3, 33) arranged in the volume upstream of the nozzle opening (10, 33), a partial flow (separation flow) of the fluid mixture enriched with the first gas is withdrawn from the zone (16) of reduced pressure and separated from a residual flow of the fluid mixture, and d. a stream of a second gas is dispersed into the residual stream by means of a gas supply (4). [11] Method according to claim 10, characterized by that a sparging gas is supplied to the fluid mixture upstream of the nozzle opening (10, 31) to separate the first gas from the fluid mixture. [12] Method according to claim 11, characterized by that a stream of the second gas is used as sparging gas. [13] Method according to one of claims 11 or 12, characterized bythat a cryogenically liquefied or pressurized gas is used as the sparging gas, the cold content of which is used to cool the separation stream and / or a gas phase separated in the separator (3, 33). [14] Method according to one of claims 10 to 13, characterized by that the separation stream of the fluid mixture withdrawn from the zone (16) for separating the first gas is subjected to a phase separation for separating the first gas from a liquid phase and the liquid phase is fed again to the nozzle (2, 26).

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