DE102013108709A1 - Device for degassing a fluid - Google Patents

Abstract

The present invention relates to a device for degassing a gas-laden fluid, comprising a container (12) in which at least one membrane module (20), with an inner side and a radial circumference, is received for separating a gas from the fluid, wherein the fluid is the membrane module (20) via its overall depth by means of an inlet (30) centrally supplied, discharged via a drain (35) on the container and the gas from the membrane module (20) via another outlet (37) on the membrane module (20) is discharged and the fluid flows through the membrane module (20) from the inside to the radial extent. The device is characterized in that the membrane module (20) is accommodated in the fluid of the container (12), the fluid in the container (12) outside the membrane module (20) having substantially uniform pressure or the pressure differences outside the membrane module (20 ) are compensated by a pressure equalization in a distribution pipe (31), so that the pressure drop of the membrane module (20) between the inside and the radial circumference over the entire construction depth is substantially constant.

Description

The present invention relates to a device for degassing a gas-laden fluid, a dispersion, suspension or emulsion. The use of a gas-laden fluid can lead to loss of quality, malfunction or even damage to the device using it. It is therefore desirable for many applications and processes a degassed fluid.

Devices and methods for degassing a gas-laden fluid are known in the art. For example, chemical methods are used, e.g. using suitable reducing agents or by means of so-called. Venting additives or by viscosity-reducing additives. Furthermore, thermal processes are known in which the fluid to be degassed is heated to a temperature in the vicinity of the boiling point. Other methods of degassing use ultrasound, resulting in the union of small bubbles to larger bubbles, which then migrate to the surface. There are also numerous degassing devices and methods based on vacuum degassing; For example, a device is used in which to a housing with the fluid, a negative pressure - often called "vacuum" - is applied; for support, a disk may still rotate in the fluid. In some devices for degassing membranes are also used. Such membranes contain in the core a cartridge, which is composed of many tubes. The walls of these tubes are permeable to gases but impermeable to liquids. The gas-loaded fluid is pressed under pressure into the inside of the cartridge, so that the cartridge is flowed through by the fluid from the inside to the outside. In this case, a vacuum is applied to the tubes, wherein the gas is withdrawn from the fluid flowing past by the difference of the partial pressure. The said cartridge is located in a pressure housing. The degassed fluid is collected at an outlet and can then be used for the intended purpose.

Among other things, this device has the following disadvantages: In the housing, a pressure gradient forms from the interior of the cartridge to the outlet opening. The flow of the fluid follows this pressure gradient. Areas of the cartridge, which are outside of this flow, are poorly or not at all flowed through. Therefore, this structure does not use the entire capacity of the membrane. Furthermore, because of the lower flow rate at the edge of this flow path, regions are formed in which the solids, e.g. from the dispersion to be degassed. As a result, these areas of the membrane are blocked by these solids, wherein the pressure in the housing further promotes this blocking. This process of blocking can be from a few minutes to several hours, depending on the nature of the dispersion. If the membrane is blocked, it can no longer be used for degassing and the degassing process may need to be interrupted for cleaning or membrane replacement. Such a device is therefore not suitable for continuous operation. If the membrane is not cleaned immediately when blocked, it can even be permanently damaged.

Against this background, it is an object of the present invention, at least partially overcome or to improve the disadvantages of the prior art.

The object is achieved with a device according to claim 1 and a method according to claim 14. Preferred embodiments and modifications are the subject of the dependent claims.

A device according to the invention for degassing a gas-laden fluid has a container in which at least one membrane module, with an inner side and a radial circumference, for the separation of a gas is taken up by the fluid. In this case, the fluid is supplied to the membrane module via its overall depth by means of an inlet centrally and discharged via a drain on the container. The gas separated from the fluid from the membrane module is removed via a further drain on the membrane module and the fluid flows through the membrane module from the inside to the radial circumference. In this case, the fluid in the container outside the membrane module substantially a uniform pressure, or the pressure differences outside the membrane module are compensated by a pressure equalization in a distribution pipe as part of the fluid supply to the membrane module, so that the pressure drop of the membrane module between the inside and the radial circumference is essentially constant over the entire construction depth.

The gas-loaded fluid may be a dispersion, suspension or emulsion. Such fluids typically have a gas content of up to several percent after their manufacture or delivery. This gas content often leads to disadvantages in the further use of the fluid. Thus, the gas content in steam or hot water systems can lead to increased corrosion or even damage to the system due to cavitation. For ink jet printers, the gas content can cause printer errors or even clogging of the nozzles. For paints, the gas content can cause a deterioration of the surface quality. In the surface finishing of Fibrous webs, such as in the paper industry, the gas content in a coating color, for example, when applied by curtain coating, roller, mop or nozzle coating, lead to a faulty paint application. For these and many other applications, it is necessary to reduce the gas content of the fluid by degassing.

For this purpose in an inventive apparatus a membrane module is used, as it is known in the art, for example as membranes of the brand Liqui-Cel ^® or SuperPhobic ^® by the company Membrana. The membrane module according to the invention is constructed from a multiplicity of substantially parallel membrane tubes, membrane tubes or hollow fibers. The walls of these tubes are permeable to gases, but impermeable to liquids, so that the gas of the gas-laden fluid can collect in these tubes. A device according to the invention is constructed such that the gas-laden fluid is supplied from the outside via an inlet centrally, ie in the radial center of the membrane module. The gas-laden fluid is continued in the radial center of the membrane module in a distribution pipe in its entire depth; this distribution tube forms the inside of the membrane module. Said membrane module is in a container which contains the degassed fluid outside the membrane module. The radial circumference of the membrane module forms the contact point for the degassed fluid. The container has a drain through which the degassed fluid can be removed. From the inside of the membrane module - the central distribution pipe - to the container, the membrane module is flowed through from the inside to the outside of the fluid. In addition, the membrane module has a further outlet, via which the gas which has been taken from the fluid is removed from the membrane module.

The membrane module is preferably completely contained in the fluid contained in said container. This is after the start of the device, the degassed output fluid. In the case of a device according to the invention, the fluid in the container outside the membrane module has essentially a uniform pressure, in the simplest case atmospheric pressure, i. neither the container nor the fluid outside the membrane module is subjected to an overpressure or negative pressure, but the container is kept open at atmospheric. A lid of this container therefore need not withstand pressure, but only serves to protect against contamination from outside or similar purposes. Because the fluid in the container outside the membrane module has substantially uniform pressure, the pressure drop of the membrane module between the inside and the radial circumference over the entire depth is substantially constant.

The device according to the invention thus has considerable advantages over the prior art: no constructional measures are required to provide the said container pressure-resistant. Furthermore, results from the inventive arrangement that the membrane module is uniformly flowed through by the fluid substantially over the entire depth between the inside and the radial circumference of the membrane module, because the pressure drop from the central inlet to the periphery of the membrane module is substantially uniform over its entire length , As a result, the flow capacity of the membrane module is much better utilized, because there is no main flow direction within the membrane module by said arrangement, but the fluid flows around all sections of all tubes of the membrane module at a certain speed. In addition, it prevents that form areas with a lower flow in which deposit the solids of the dispersion. The membrane module is thus not blocked by the solids of this dispersion. For these reasons, it results as a further advantage that the device according to the invention is suitable for continuous operation.

In one embodiment of the invention, a membrane module may be so long and substantially vertical in the starting fluid that the hydrostatic pressure of the fluid causes the fluid in the container outside the membrane module to no longer have a uniform pressure. This would lead to different pressure differences over the depth of the membrane module without compensation. For this reason, in such an arrangement of the membrane module whose inside - so the distribution pipe - by influencing the flow, for example by adapted flow barriers, be designed so that the pressure drop of the membrane module between the inside and the radial circumference over the entire depth is substantially constant is.

In one embodiment of the device according to the invention, the fluid in the container outside the membrane module is at substantially atmospheric pressure.

As mentioned above, neither the container nor the fluid outside the membrane module is subjected to a positive or negative pressure, but the container is kept open at atmospheric. A lid of this container therefore need not withstand pressure, but only serves to protect against contamination from outside or similar purposes. An embodiment of the container thus has an overpressure of 0 bar. However, another embodiment of the container can - for example, for reasons of safety or to further reduce contamination from the outside - a slight overpressure (between 0 and 1 bar) have.

In order to carry out the degassing effectively, it makes sense to apply a negative pressure to the outlet of the membrane module for the gas, preferably a negative pressure of 50 to 800 mbar and in particular a negative pressure of 300 to 400 mbar, in each case based on the atmospheric pressure of the environment.

The gas-laden fluid is acted upon in a device according to the invention with an overpressure to supply it to the central inlet of the membrane module. In this case, an overpressure of 1 to 12 bar and in particular an overpressure of 1 to 8 bar is preferably applied to the fluid at the inlet, in each case based on the atmospheric pressure of the environment. As a result, both a differential pressure compared to the degassed fluid in the housing is constructed and a partial pressure relative to the gas, which is withdrawn from the fluid by means of negative pressure.

The membrane module, as used for a device according to the invention, has a multiplicity of membrane tubes or membrane tubes. In particular, it has hydrophobic membrane hollow fibers made of at least one of the materials selected from a group consisting of polysiloxanes and / or their derivatives, fluoroelastomers such as fluororubber (FKM), polytetrafluoroethylene and / or derivatives thereof, polyolefins, and / or their derivatives, polyethylene and polypropylene, combinations thereof and the like.

The said membrane tubes or membrane tubes, in particular also the hydrophobic membrane hollow fibers, are preferably arranged substantially parallel to a distribution tube following the inlet for the fluid. Thus, the membrane tubes are arranged perpendicular to the main flow direction. By this arrangement, a close contact and a large contact surface between the fluid and the membrane tubes is ensured, and thus an efficient degassing.

The membrane tubes or membrane tubes, in particular also the hydrophobic membrane hollow fibers, are arranged in a fabric.

In a first embodiment, the central distribution tube is cylindrically shaped, i. with the same diameter over the entire length of the distribution pipe. A further advantageous embodiment has a variable diameter over the length of the distribution tube, resulting in a conical shape. With this configuration, pressure differences between the central inlet and the opposite end of the distribution pipe can be compensated. In particular, a cross-flow distributor can be used to compensate for differences in pressure between the inlet side and the end section of the feeder, or else pressure differences which are caused by the arrangement of the membrane module, e.g. caused in the vertical direction, already considered in the design of the device and adjust accordingly. As a result, e.g. be ensured that the differential pressure between the inside and outside of the membrane module is kept constant over the depth of the module and thus a uniform application of the module or all membrane tubes can be achieved.

The membrane tubes or membrane tubes, in particular also the hydrophobic membrane hollow fibers, are arranged on a plurality of circular radii, which are arranged substantially coaxially to the distribution tube.

Turbulence generators, preferably in the form of an agitator, are arranged in the container and outside the membrane module. By such a stirrer, the degassed fluid is in continuous motion. This continuous movement prevents sticking or blocking of the degassed fluid in the container by separating the components of the dispersion. Such blocking could lead to a loss of performance of the device or even damage the device. However, it must be avoided that additional gas is introduced into the already degassed fluid by the stirring. This can be done, for example, that the container is closed by the outside air or by the arrangement and / or speed of the agitator no air is introduced into the fluid.

In a further embodiment, the container is designed to be closed and has a pressure compensation device. This configuration prevents contaminants or air from being introduced into the container. Another advantage is that the hardening of the surface - forming a so-called "skin" - thus significantly reduced. This effect can be further enhanced in a further embodiment by an increased humidity. The pressure compensating device associated with these embodiments causes the pressure in the container to continue to substantially not exceed the ambient atmospheric pressure, thereby maintaining the beneficial effects and advantageous non-pressurized design of the device.

The fluid is a suspension, emulsion or dispersion, as is preferably used for painting paper, board or paperboard, and more preferably a solids content between 5 and 75% by weight, preferably between 35 and 70% by weight and especially between 65 and 70% by weight. However, this does not mean that a device according to the invention is limited to these fluids. One skilled in the art can readily determine other uses for this device from the advantageous features of the present invention, for example, for various types of printing inks, such as those used for ink jet printers, for paints, casting resins, in plastics manufacturing, or the like.

The device may comprise only one or a plurality of membrane modules. For a relatively simple scalability of a system according to the invention with increased power requirements can be achieved. In a further embodiment, this device is also cascadable in order to carry out an even further degassing.

Another embodiment of the present invention is a method for degassing a gas-laden fluid, comprising the steps of:
Introducing the gas-laden fluid, in particular a coating color, by means of an overpressure into an inlet of the fluid on an outer surface of membrane tubes of a membrane module;
Applying a negative pressure on the inside of the membrane tubes of the membrane module for discharging the gas separated from the fluid;
the fluid flows through the membrane module and its membrane tubes from the inside to the outside;
Receiving the degassed fluid immediately outside the membrane module in a substantially pressure-free container;
Discharge of the degassed fluid via a further drain on the container.

These steps are by no means to be considered strictly serial steps. Rather, they also partially run parallel during a process according to the invention.

Moreover, the explanations given to the devices according to the invention also apply mutatis mutandis to the method according to the invention.

A device according to the invention can be used for degassing a multiplicity of gas-laden fluids, in particular a dispersion, suspension or emulsion. Particularly suitable is a device according to the invention for degassing a dispersion, suspension or emulsion, consisting at least of water, binder and pigment, as it is preferably used for brushing paper, cardboard or board, and further preferably a solids content between 5 and 75 weight %, preferably between 35 and 70% by weight and in particular between 65 and 70% by weight, or of a coating color for use in curtain coating, roll coating, sump coating or jet coating in paper finishing.

The invention will be described with reference to various embodiments, wherein it should be noted that the invention is not limited to the embodiment shown here, but rather also corresponding modifications in the sense of the present invention.

Showing:

1a a schematic representation of a device for degassing according to the prior art in a longitudinal section;

1b a schematic representation of a device for degassing according to the prior art in a cross section;

2a a schematic representation of a device according to the invention for degassing in a longitudinal section;

2 B a schematic representation of a device according to the invention for degassing in a cross section;

3 a schematic representation of another device according to the invention for degassing in a longitudinal section.

1a shows schematically a device for degassing 1 according to the prior art in a longitudinal section. There is a membrane module 20 in a pressure-resistant housing 10 , The membrane module 20 is via a feeder 30 correspond to the arrow supplied with the gas-laden fluid. This gas-laden fluid is located at the feeder 30 under an overpressure preferably of several bar, based on the ambient pressure outside the housing 10 , This overpressure forces the gas-laden fluid - as indicated by arrows 33 displayed - in the membrane module 20 , This membrane module 20 is made of membrane pipes or membrane hoses 21 constructed, which are substantially parallel to the axis and on concentric radii to the distribution pipe 31 are arranged. At a drain for the gas 37 a vacuum pump is installed, which is the negative pressure for the degassing in the membrane pipes or membrane hoses 21 generated. The degassed fluid is at a drain 35 taken. This forms in the housing 10 a pressure gradient and there is a flow from the distribution pipe 31 the end 35 , It is flowed through Part of the membrane module 25 relatively narrow. Regions of the membrane module 20 that are outside of this flow 25 lie, are poorly or not at all flowed through. Therefore, with this structure, not the entire capacity of the membrane module 20 used. Furthermore, due to the lower flow at the edge of this flow pattern 25 Areas where the solids of the dispersion settle. This will make these areas of the membrane module 20 blocked by these solids, with the pressure in the housing 10 this blocking additionally promotes. This process of blocking can be from a few minutes to several hours, depending on the nature of the dispersion. When the membrane module 20 blocked, it can no longer be used for degassing and the degassing process must be interrupted. Such a device is therefore not suitable for continuous operation. Will the membrane module 20 if it is not cleaned immediately, it can even be permanently damaged.

1b shows schematically the device for degassing 1 from 1a in a cross section, wherein the reference numerals have the same meaning as in 1a to have.

It is clearly the relatively narrow flowed through part of the membrane module 25 seen from the distribution pipe 31 the end 35 extends. The other areas of the membrane module 20 are significantly less or not at all flowed through, so that there form the aforementioned deposits of the dispersion.

2a shows a schematic representation of a device according to the invention for degassing 1 in a longitudinal section. In this embodiment, the membrane module 20 in a container 12 arranged horizontally. This container is atmospherically open, ie it preferably has an overpressure of 0 to 1 bar, particularly preferably an overpressure of 0 to 0.5 bar and in particular an overpressure of 0 to 0.1 bar, in each case based on the atmospheric pressure of the environment, on. In particular, prevails throughout the container 12 essentially the same pressure.

In a further embodiment, the container 12 also a lid (not shown), which the container 12 closes up. Above all, this cover has a protective function, eg against contamination from the outside, but it should not affect the pressure of the container 12 increase significantly. If such an increase in pressure is unavoidable due to the structural arrangement, then a pressure equalization device can be mounted which controls the pressure in the container 12 limited.

In the example shown, the membrane module 20 completely in the degassed fluid 40 located in said container 12 is located, and it is at a distance 15 below the level of degassed fluid 40 , About a feeder 30 becomes the membrane module 20 supplied with the gas-laden fluid. The gas-laden fluid is under an overpressure, depending on the embodiment, approximately between 1 and 12 bar, in particular between 1 to 8 bar, based on the environment outside the container 12 , may be. This creates an overpressure in the distribution pipe 31 , To the pressure in the distribution pipe 31 To keep even as possible, this can not only be cylindrical, but also conical or held in another favorable for the uniformity of the pressure form; In particular, the distribution pipe 31 also be designed as a cross-flow distributor.

Around the distribution pipe 31 are clearly a variety of membrane tubes or membrane tubes 21 to see. These are designed as hydrophobic membrane hollow fibers, which are preferably substantially parallel to the distribution tube 31 following the inlet for the fluid 30 are arranged. These membrane hollow fibers are impermeable to liquids but permeable to gases. Therefore, the inside of the hollow membrane fibers is with a drain for the gas 37 connected to which a vacuum pump is connected. With this vacuum pump is preferably a negative pressure of 50 to 800 mbar and in particular a negative pressure of 300 to 400 mbar, each based on the atmospheric pressure of the environment applied.

The membrane hollow fibers mentioned can be arranged in a fabric with which the distribution tube 31 is surrounded. From these hollow membrane fibers is the membrane module 20 built up. The hollow membrane fibers are from the gas-laden fluid, from the distribution tube 31 to the radial extent of the membrane module 20 , Because the entire circumference of the membrane module 20 is substantially under the same pressure, forms over its entire radial extent the same pressure difference to the distribution pipe 31 out; therefore, the entire membrane module becomes 20 flows through substantially uniformly from the fluid, ie, the flowed through areas of the membrane module 25 essentially comprise the entire membrane module 20 , This results in an inventive advantage that much larger areas of the membrane module 20 can be used for degassing; this leads to a substantial increase in the flow rate of the membrane module 20 , Furthermore, it is largely avoided with a device according to the invention that the solids of the dispersion in the membrane module 20 settle and thereby block the membrane module. For this reason, a device according to the invention can also be used in continuous operation. Only contaminants of the supplied fluid, which could block the membrane module, must be avoided.

Another embodiment of the invention has turbulence generators, preferably in the form of an agitator 50 , which keep the degassed fluid in slow motion. This will avoid getting in the container 12 outside the membrane module 20 Blockages form the operation of the device 1 could disturb. Of course, other turbulence generators can be used for this use, such as flow-generating nozzles or the like.

In 2a is just a membrane module 20 shown. However, this is not intended to be a limitation of the present invention. Precisely because that container 12 can be designed without pressure, a scalability of the device, depending on the required flow rate, relatively easy to do: A device according to the invention can either a variety of membrane modules 20 in a container 12 but it can also be several devices 1 operated in parallel, or a combination of these two embodiments.

2 B shows schematically the device for degassing 1 from 2a in a cross-section; the reference numbers have the same meaning as in 2a , It can clearly be seen how the membrane module 20 at a distance 15 located below the surface of the degassed fluid. Furthermore, it can be seen how the fluid is in all directions from the distribution pipe 31 to the radial extent of the membrane module 20 flows, so that the flowed through areas of the membrane module 25 essentially the entire membrane module 20 include. Here are the flow around membrane tubes or membrane hoses 21 to be seen in a supervision. At the bottom of the container 12 is the process 35 to see for the degassed fluid. The feeder 30 the gas-laden fluid and the drain 37 for the withdrawn gas are shown schematically.

3 schematically shows a further embodiment of the invention, in which the membrane module 20 vertically in the pressureless container 12 is arranged; the reference numbers have the same meaning as in 2a and 2 B , Again, it can be seen again that the membrane module 20 at a distance 15 located below the surface of the degassed fluid. The feeder 30 the gas-laden fluid and the drain 37 for the extracted gas are arranged at the top in this embodiment; Alternatively, this can also be done from below. The remaining embodiments according to the invention and extensions, as for 2a have been explained, apply here analogously.

In one embodiment of the invention, the overall depth 22 be so large that the hydrostatic pressure of the fluid causes the fluid in the container 12 outside the membrane module 20 no longer has a uniform pressure. That would without compensation to different pressure differences over the depth 22 of the membrane module 20 to lead. For this reason, with such an arrangement of the membrane module 20 its inside - so the distribution pipe 31 - By influencing the flow, for example by adapted flow barriers, be designed so that the pressure drop of the membrane module 20 between its inside 31 and the radial circumference over the entire construction depth 22 is essentially constant.

LIST OF REFERENCE NUMBERS

1

Device for degassing

10

casing

12

container

15

Level via membrane module

20

membrane module

21

Diaphragm pipes or membrane hoses

22

Construction depth of the membrane module

25

perfused part of the membrane module

30

Feeding gas-laden fluid

31

distribution tube

33

arrows

35

Drain degassed fluid

37

Drain gas

40

degassed fluid

50

agitator

Claims (17)

Apparatus for degassing a gas-laden fluid, comprising a container ( 12 ), in which at least one membrane module ( 20 ), having an inside and a radial circumference, for the separation of a gas from the fluid is received, wherein the fluid of the membrane module ( 20 ) via its overall depth by means of an inlet ( 30 ) centrally, via a sequence ( 35 ) discharged from the container and the gas from the membrane module ( 20 ) about a further process ( 37 ) on the membrane module ( 20 ) is discharged and the fluid is the membrane module ( 20 ) flows through from the inside to the radial circumference, characterized in that the fluid in the container ( 12 ) outside the membrane module ( 20 ) has substantially a uniform pressure or the pressure differences outside the membrane module ( 20 ) by a pressure equalization in a distribution pipe ( 31 ) are compensated, so that the pressure drop of the membrane module ( 20 ) is substantially constant over its entire depth between its inside and the radial circumference. Apparatus according to claim 1, characterized in that the fluid in the container ( 12 ) outside the membrane module ( 20 ) has substantially atmospheric pressure. Device according to claim 1 or 2, characterized in that at the outlet ( 37 ) for the gas, a negative pressure, preferably a negative pressure of 50 to 800 mbar and in particular a negative pressure of 300 to 400 mbar, in each case based on the atmospheric pressure of the environment, is applied. Device according to one of the preceding claims, characterized in that at the inlet ( 30 ) of the fluid, an overpressure, preferably an overpressure of 1 to 12 bar and in particular an overpressure of 1 to 8 bar, in each case based on the atmospheric pressure of the environment, is applied. Device according to one of the preceding claims, characterized in that the membrane module ( 20 ) a plurality of membrane tubes or membrane tubes ( 21 ), in particular hydrophobic membrane hollow fibers made of at least one material selected from a group comprising polysiloxanes and / or derivatives thereof, fluoroelastomers such as fluororubber / FKM, polytetrafluoroethylene and / or derivatives thereof, polyolefins, and / or their derivatives Derivatives, polyethylene and polypropylene, combinations thereof, and the like. Device according to claim 5, characterized in that the membrane tubes or membrane tubes ( 21 ), in particular also the hydrophobic membrane hollow fibers, preferably substantially parallel to a distribution tube ( 31 ) following the feed to the fluid ( 30 ) are arranged. Apparatus according to claim 5 or 6, characterized in that the membrane tubes or membrane tubes ( 21 ), in particular also the hydrophobic membrane hollow fibers, are arranged in a fabric. Device according to one of claims 6 or 7, characterized in that the central distribution pipe ( 31 ) is cylindrical or conical, in particular as a cross-flow distributor, designed. Device according to one of claims 6 to 8, characterized in that the membrane tubes or membrane tubes ( 21 ), in particular also the hydrophobic membrane hollow fibers, are arranged on a multiplicity of circular radii which are substantially coaxial with the distribution tube ( 31 ) are arranged. Device according to one of the preceding claims, characterized in that in the container ( 12 ) and outside the membrane module ( 20 ) Turbulence generators, preferably in the form of an agitator ( 50 ) are arranged. Device according to one of the preceding claims, characterized in that the container ( 12 ) is executed closed and has a pressure compensation device. Device according to one of the preceding claims, characterized in that the fluid is a suspension, emulsion or dispersion, as it is preferably used for brushing paper, cardboard or paperboard and further preferably a solids content of between 5 and 75% by weight, preferably between 35 and 70% by weight and especially between 65 and 70% by weight. Device according to one of the preceding claims, characterized in that the device comprises a plurality of membrane modules ( 20 ) having. Method for degassing a gas-laden fluid, comprising the steps of: - introducing the gas-laden fluid, in particular a coating color, by means of an overpressure into an inlet ( 30 ) of the fluid on an outer surface of membrane tubes ( 21 ) of a membrane module ( 20 ); - applying a negative pressure on the inside of the membrane tubes ( 21 ) of the membrane module ( 20 ) for removal ( 37 ) of the gas separated from the fluid; The fluid flows through the membrane module ( 20 ) and its membrane tubes ( 21 ) from the inside to the outside; - Recording the degassed fluid immediately outside the membrane module ( 20 ) in a substantially pressure-free container ( 12 ); - discharging the degassed fluid via a further sequence ( 35 ) on the container ( 12 ). A method according to claim 14, characterized in that the membrane module ( 20 ) substantially uniform pressure across the radial circumference of the membrane module ( 20 ), preferably an overpressure of 0 to 1 bar, particularly preferably an overpressure of 0 to 0.5 bar and in particular an overpressure of 0 to 0.1 bar, in each case based on the atmospheric pressure of the environment having.  Method according to one of claims 14 or 15 for degassing a fluid using a device according to one of claims 1 to 13. Use of the device 1 according to claim 1 to 12 for degassing a gas-laden fluid, in particular a suspension, emulsion or dispersion consisting at least of water, binder and pigment, as it is preferably used for brushing paper, cardboard or paperboard and further more preferably a solids content between 5 and 75% by weight, preferably between 35 and 70% by weight and in particular between 65 and 70% by weight, or of a coating color for use in curtain coating, roll coating, sump coating or jet coating in paper finishing.

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