Liquid separator for a compressor system, coarse separator for such a liquid separator, and liquid separation system

Abstract

The present invention relates to a liquid separation device for a compressor system, comprising a rough separator (30, 30', 30'', 30''') having at least one separation surface, and at least one mixture supply (20, 20', 20'', 20''') configured to supply an air-liquid mixture (70) to the separation surface, the mixture supply (20, 20', 20'', 20''') being formed with a mixture supply outlet facing the separation surface, the mixture supply outlet being positioned relative to the separation surface of the rough separator (30, 30', 30'', 30''') such that a mixture flow (70a) contacting the separation surface is guided substantially tangentially over at least one section of the separation surface.

Description

[Technical Field]

[0001] The present invention relates to a liquid separator for a compressor system, to a rough separator for such a liquid separator, and to a liquid separation system comprising such a liquid separator and / or such a rough separator.

[0002] In compressor systems, such as those with oil-lubricated screw compressors, the air compressed by the compressor may contain oil used for lubrication and cooling. To retain the oil within the compressor system for further use or at least reduce excess oil discharge to the outside environment, a liquid separation system, or in this case, an oil separation system, is used. Such a liquid separation system may include, for example, a coarse separator and a fine separator. A simple, maintenance-free structure is used for the coarse separator. The compressed air-oil mixture is guided from the compressor through a pressure tube section at a relatively large angle toward this structure, also known as a baffle plate. Depending on the impact speed and impact angle, the collision of the air-oil mixture generates oil droplets of various sizes. Larger droplets are gravity-driven and reach the oil pan directly from the baffle plate or in the area near the baffle plate. However, smaller droplets resulting from the collision are further transported by the mixture flow toward the fine separator as a secondary spray. The higher the percentage of oil remaining in the air-oil mixture reaching the fine separator, the shorter the service life of the fine separator or of the coalescing filters used for it, for example. Furthermore, the compressor system becomes less efficient the more oil is sucked into the fine separator.

[0003] In view of the above, the problem underlying the present invention is to provide a liquid separation device for a compressor system, a rough separator for such a liquid separation device, and a liquid separation system comprising such a liquid separation device and / or such a rough separator, which can increase the efficiency of liquid separation for a compressor system.

[0004] This object is achieved by a liquid separation device, a coarse separator and a liquid separation system according to the parallel independent claims. Advantageous further configurations of the invention are contained in the dependent claims.

[0005] According to the present invention, a liquid separation device for a compressor system includes a coarse separator having at least one separation surface and at least one mixture supply configured to supply an air-liquid mixture to the separation surface, the mixture supply being formed with a mixture supply outlet facing the separation surface, the mixture supply outlet being arranged relative to the separation surface of the coarse separator such that a mixture flow contacting the separation surface is guided substantially tangentially over at least one section of the separation surface, and more preferably such that it enters the separation surface tangentially, i.e., the mixture flow impinges on the separation surface tangentially.

[0006] The mixture supply can be, for example, a pressure tube, through which the air-liquid mixture from the compressor is guided and can be fed to the coarse separator via a pressure tube outlet serving as a mixture supply discharge. The mixture supply or mixture supply discharge is oriented so that it flows substantially tangentially through the separation surface of the coarse separator to separate the liquid from the air-liquid mixture, or at least at an angle that allows substantial, i.e., at least almost tangential, further guidance of the mixture flow along the separation surface. This ensures that the mixture flow is guided mostly in contact with the separation surface, rather than mostly bouncing off the separation surface. In other words, by appropriately positioning the mixture supply or mixture supply discharge relative to the separation surface, the impact angle of the air-liquid mixture with the separation surface is smaller than in the case of separation surfaces used in the context of baffle plates. The impact angle between the incoming air-liquid mixture and the separation surface from the direction of the incoming air-liquid mixture is, in particular, between 0° and 50°, preferably between 0° and 40°, and particularly preferably between 0° and 30°. The mixture flow guided tangentially along the separation surface is then braked essentially by friction and the expansion of the flow cross section, causing the liquid to at least partially separate from the mixture flow. The stronger the braking of the mixture flow, the larger the droplets that are separated by gravity. The friction and the expansion of the flow cross section can both be determined by the distance the mixture flow is guided along the separation surface. For example, other conditions being equal, a relatively long distance also results in a higher braking effect. The tangential guidance of the mixture flow along the separation surface further reduces the proportion of secondary spray. In particular, the proportion of secondary spray is reduced by selecting a tangential guidance of the mixture flow such that flow resistance and stagnation pressure, which may be caused by vortices or turbulence, are kept small or even completely avoided.

[0007] The increase in the number of liquid or oil droplets separated at the separation surface and already in a liquid pan, such as an oil pan, and the reduction in secondary spraying improve the efficiency of the compressor system and the service life of further downstream liquid separators, such as fine separators.Since liquid separation at the separation surface of the coarse separator is no longer based solely on the impact angle and impact speed, as in the case of baffle plates, it is now also influenced by the guidance along the separation surface and the associated friction and braking effects, which opens up more geometric possibilities for the coarse separator.

[0008] The liquid may be oil or an oil-containing liquid for cooling and / or lubricating the compressor system. Alternatively, however, other liquids or liquid mixtures that provide cooling and / or lubrication within predetermined specifications may be used. In the following, the terms "oil" and terms that include "oil" may also be used synonymously with the term "liquid." The term "oil" therefore also includes oil substitutes or other cooling and / or lubricating liquids for use in compressor systems.

[0009] In one configuration, the cross section of the mixture feed outlet facing the separation surface is less than or equal to the exit area of ​​the mixture stream from the coarse separator, in particular less than half of this exit area, and preferably less than one-third of this exit area.

[0010] The design of the mixture feed outlet, which is small compared to the outlet area of ​​the mixture stream, helps to increase the flow cross section of the mixture stream. This allows for a higher braking effect and therefore a higher separation rate. In this case, it is particularly advantageous for the ratio of the cross section of the mixture feed outlet to the outlet area of ​​the mixture stream leaving the coarse separator to be 1:3 or less. In this case, the outlet area of ​​the mixture stream leaving the coarse separator corresponds to the area of ​​the opening in the coarse separator provided for the outlet of the mixture stream leaving the coarse separator. In other words, the flow cross section of the mixture feed stream as it enters the coarse separator is particularly smaller than the outlet area relevant in flow technology for the mixture stream as it leaves the coarse separator.

[0011] In one configuration, the mixture supply is fixedly connected or connectable to the coarse separator.

[0012] This allows the mixture supply outlet to be arranged in a fixed position relative to the separation surface, so that the flow characteristics of the mixture flow along the separation surface are affected only by the tolerances of the connection between the mixture supply section and the coarse separator from a geometrical point of view. Therefore, compared to, for example, assembling a mixture supply section and a coarse separator separately in each casing section of a compressor system, the fixed connection between the mixture supply section and the coarse separator has a smaller fluctuation range in relative position, and thus the separation results are more reproducible. This also facilitates the reuse of the mixture supply section with the coarse separator and / or the use of such a combination, since time-consuming adjustment processes can be omitted or at least performed outside each casing section.

[0013] According to a further configuration, the mixture supply section and the coarse separator are connected by means of connecting means, in particular by at least one connecting web, preferably by three connecting webs, which are further preferably formed to be deformable.

[0014] These connecting means can hold the mixture supply in a fixed position relative to the coarse separator. For example, the connecting webs can be configured as connecting means for positioning the mixture supply outlet at a predetermined distance and angle relative to the separation surface. Thus, the connecting webs are connected or can be connected to both the mixture supply and the coarse separator. The stability of the fixed connection can be further enhanced by using multiple connecting webs, for example, three connecting webs spaced approximately 120° apart around the mixture supply or the mixture supply outlet. To compensate for errors or adapt the impact angle, at least one connecting web can be deformable. In this case, the deformation can be plastic, for example, or elastic, if elastic deformation is possible.

[0015] As an alternative to using a connecting web, the mixture supply can also be fixed in position in another way and connected to the coarse separator via a connecting means, for example, the mixture supply can be screwed into a mixture supply holder formed by the coarse separator.

[0016] In particular, the relative positions of the mixture feed and the coarse separator are adaptable via an adapting device.

[0017] Alternatively or additionally to the deformability, for example, at least one connecting web can be telescopically variable in length. In this case, the connecting web itself has a corresponding adapting device. However, the mixture supply and / or the coarse separator can also have an attachment device for at least one connecting web, so that the connecting web can be attached to the mixture supply and / or the coarse separator in various length sections. In the above-mentioned example of screwing the mixture supply into the mixture supply holder formed by the coarse separator, the adapting device can also be adjustably screwed in, for example, via cooperation of the threads of the mixture supply and the mixture supply holder.

[0018] Via the adaptation device, deviations based on errors from a predetermined relative position of the mixture supply part with respect to the coarse separator can be corrected, or even completely different relative positions can be adjusted, for example, for intentionally changing the flow characteristics of the mixture flow.

[0019] The adapting device may be configured to be controlled via a control device to control and adapt the relative position. For example, the position-changing device may be connected to a monitoring device that detects deviations from a predetermined relative position. Deviations can be detected directly via position detection and / or indirectly via flow measurement. Alternatively or additionally, the control device can also control the relative position depending on the operating mode of the compressor, the impingement velocity of the air-liquid mixture on the separation surface, and / or the state of the fine separator. For example, a larger impingement angle can be adjusted when the impingement velocity of the air-liquid mixture on the separation surface is low. Since the risk of secondary spraying is low when the impingement velocity is relatively low, the separation surface can therefore be used partially as a baffle plate.

[0020] In one configuration, the connection between the mixture supply and the coarse separator is made detachable.

[0021] The mixture feed or the coarse separator can therefore be replaced independently and then reconnected to one another in a fixed manner.

[0022] Alternatively, the mixture supply and the coarse separator are integrally formed.

[0023] For example, the mixture supply section and the coarse separator may be monolithically or permanently connected to one another. Due to the rigidity of the integral construction, the fixed connection between the mixture supply section and the coarse separator is relatively insensitive to changes in normal operating conditions. However, instead of a rigid construction, the integral construction may further include a deformable element at least in a predetermined section, which allows the relative position to be adjusted. For example, at least one connecting web may have a swan-neck section or a bent arm section as the deformable element at least in a predetermined section, which allows for reversible changes in the relative position. Depending on the material selection and / or dimensioning of the at least one connecting web or a section thereof, the at least one connecting web or a section thereof may alternatively or additionally be deformed at least in a predetermined section. Due to the deformation, the relative position between the mixture supply section and the coarse separator, and thus the impact angle of the mixture flow with respect to the separation surface, can be adjusted.

[0024] According to a further configuration, the separating surface of the coarse separator facing the mixture supply section is configured with a substantially concave curve at least in a cross-sectional section through which the mixture flow must flow, and the mixture supply section is arranged so that the mixture flow is guided substantially along the concave curvature at least in a certain section.

[0025] The radius of curvature of the concave curvature may be constant or variable. Since the mixture supply section faces the concave curvature, the mixture flow can be guided through the concave curvature and therefore extends in a circular arc, so to speak. This supports the tangential guidance of the mixture flow along the separation surface and also brakes the mixture flow. Thus, the flow trajectory of the mixture flow mimics the cross-sectional section through which the mixture flow must flow.

[0026] In particular, the separation surface of the coarse separator is formed in the form of a parabola or a dome, in particular a dome tapering conically towards the dome tip, and the mixture supply section is arranged in such a way that the mixture flow is guided from at least one side of the separation surface to the other side of the separation surface via the parabolic turning point or the dome arch.

[0027] If the coarse separator is formed as a cone with a rounded dome tip, e.g., a dome arch, and is open on the opposite side of the dome tip, the mixture supply can be arranged in this open area of ​​the cone. However, the dome arch can alternatively be formed by a separate, concavely curved section of the coarse separator relative to the dome tip. The separation surface is formed by the inner surface of the cone. In this case, the mixture supply outlet is oriented, for example, so that the air-liquid mixture flows tangentially along the cone surface facing the cone's axis of symmetry toward the dome arch, and then flows from the dome arch along the opposite cone surface back toward the cone opening. Thus, the cross section through which the mixture flow must pass can be a cross section of the cone cross section passing through the dome arch and can be parallel to the cone's axis of symmetry. Generally, the cross section through which the mixture flow must pass is a cross section of the dome arch that includes the curvature of the dome arch. In this case, the conical configuration of the separation surface can differ from that of a rotationally symmetric cone. However, the above description is also applicable to such a configuration, and in this case the axis of symmetry can be replaced by a longitudinal axis extending from the open side of the conical body to the dome arch or dome tip. Similarly, the separation surface of the coarse separator can have another concave curved shape. In a parabolic configuration of the separation surface, the mixture flow is guided at least through the curvature of the parabolic separation surface, which has a turning point in the flow direction of the mixture flow. This section corresponds to the turning point of the parabola.

[0028] Alternatively, the separation surface of the coarse separator forms a parabolic, cylindrical or conical body having at least one open first end face, in particular a closed second end face of a cylindrical body, or a closed second end section opposite the open first end face of the parabolic or conical body, and the mixture supply section is formed in such a way that the mixture flow is guided tangentially along the parabolic, cylindrical or conical section surface in the circumferential direction of the parabolic, cylindrical or conical body towards the open first end face.

[0029] In the case of a parabolic or conical body, the open first end face is in particular a more divergent end face than the tapered section. A parabolic, cylindrical, or conical body, as a concavely curved body, has a longitudinal axis that is surrounded by the concave curvature formed by the body. Therefore, in the case of a rotationally symmetric cylinder or cone, the longitudinal axis is the axis of symmetry. The mixture supply or mixture supply outlet is arranged so that the air-liquid mixture impinges on the separation surface in the direction of the open first end face and is then guided tangentially along the separation surface in the circumferential direction toward the open first end face.

[0030] In the case of a cylindrical object, the mixture flow can be guided spirally along the inner surface of the cylinder as a separating surface toward the open first end face. Depending on the inclination angle of the mixture feed outlet and thus the inclination angle of the impingement angle of the air-liquid mixture toward the open first end face, the tangential guide distance of the mixture flow and / or the number of rotations of the mixture flow around the longitudinal axis of the concavely curved object can be adjusted. The inclination angle can also reduce the risk of mixture flows overlapping in the direction of the longitudinal axis, thereby avoiding vortex flows. In this case, the cross-section through which the mixture flow must pass lies in a plane that intersects the longitudinal axis of the concavely curved object at each inclination angle of the mixture flow. In the case of multiple rotations around the longitudinal axis, several sections of the cross-section through which the mixture flow must pass follow one another in the direction of the longitudinal axis.

[0031] As long as the second end of the cylinder or the closed end section opposite the open first end of the parabolic or conical body is closed, it can be ensured that the air-liquid mixture or part of the mixture flow will not escape through the second end of the cylinder or the closed end section opposite the open first end of the parabolic or conical body, and thus the mixture flow will be forced out of the open first end in a controlled manner.

[0032] In particular, the separation surface is curved so that the mixture flow can be deflected by at least 90°, in particular 120°, preferably 150°, and even more preferably 170° from the flow direction at the time of exiting the mixture feed section until it leaves the coarse separator.

[0033] The concave curvature, or one of the configurations described above, therefore has a separation surface that is curved in the flow direction of the mixture flow by at least 90°, in particular 120°, preferably 150°, and even more preferably 170°, at least over the distance of the mixture flow. The resulting deflection of the mixture flow can cause a pressure loss that brakes the mixture flow again. This braking action can further increase the separation rate.

[0034] In one configuration, the parting surface is at least partially contoured and / or has a friction enhancing surface.

[0035] In this case, the term "friction-enhancing surface" refers to a surface that generates higher friction than, for example, a polished surface. Since the separation of liquid from the mixture flow by tangential flow along the separation surface is based on friction and braking, this effect is at least partially promoted by the friction-enhancing surface. The friction coefficient can be adjusted, for example, by increasing the roughness. Alternatively or additionally, a corresponding coating can be provided on or form the separation surface. Alternatively or additionally, the separation surface can be at least partially profiled. The profile can equally contribute to increasing friction as a surface structuring feature. Alternatively or additionally, profiled features, for example in the form of small recesses, can partially trap or further brake the mixture flow for separation of the liquid from the mixture flow. Furthermore, alternatively or additionally, the profiled features can guide the mixture flow in a predefined mixture flow trajectory to avoid or at least reduce vortices and / or to restrict or intentionally guide the mixture flow to a predetermined area. For example, the cylindrical body described above can have a groove extending spirally about the longitudinal axis from the second end face to the open first end face, in which the mixture flow is guided substantially tangentially. The distance between the opposing groove walls, i.e., the groove width, can in this case increase continuously or in successive sections toward the open first end face, so that an additional braking or slowing effect occurs due to the spreading of the mixture flow.

[0036] A further aspect of the invention is a rough separator for a liquid separation device as described above, wherein the separation surface is configured as described for the liquid separation device, so that the mixture flow can be introduced tangentially and braked, in particular by widening the flow cross section, by deflecting the flow direction and / or by friction along the separation surface.

[0037] As described above with regard to the various possible configurations of the separation surface, the coarse separator is configured so that the tangentially introduced mixture flow can be braked by friction, particularly in relation to the distance defined for the flow along the separation surface. Braking can be further assisted by appropriate surface characteristics of the separation surface, an increase in the flow cross section according to the ratio between the flow cross section of the mixture flow entering the coarse separator and the flow cross section of the mixture flow exiting the coarse separator, and / or a change in flow direction. This not only allows for the formation of relatively large droplets for separation, but also reduces secondary spraying. The above-described configurations of the coarse separator and the associated advantages, as described for the liquid separation device, are therefore directly applicable to the coarse separator as well.

[0038] In a further aspect, the present invention relates to a liquid separation system comprising the above-mentioned liquid separation device and / or the above-mentioned coarse separator, in which the liquid separation device is arranged in the liquid separation system in such a way that the mixture stream leaves the coarse separator with at least a vertical flow portion, in particular with a flow portion directed in the direction of gravity, and / or the liquid separation system comprises a further liquid separator, which is arranged in such a way that the mixture stream can be fed to the further liquid separator in a flow direction against gravity, at least in a certain section.

[0039] Thus, the mixture flow emerging from the coarse separator can first be directed toward a liquid pan, and then the mixture flow is supplied against gravity toward another liquid separator. The separation surface of the coarse separator is in this case particularly open toward the liquid pan in the direction of gravity, at least in a predetermined section, so that liquid separated from the mixture flow on the separation surface can be collected in the liquid pan in the direction of gravity. Preferably, the separation surface is completely open toward the liquid pan in the direction of gravity, so that no liquid is collected in the region of the separation surface. In this case, the mixture supply section can be arranged so that it penetrates the liquid pan and the mixture supply outlet is located above a predetermined maximum liquid pan level in the direction of gravity.

[0040] In an alternative or complementary embodiment, the further liquid separator is arranged downstream of the coarse separator in the flow direction of the mixture stream. The mixture supply is therefore arranged so that the air-liquid mixture first impinges on the coarse separator, and then, after flowing tangentially along the separation surface, it can be fed to the further liquid separator against gravity. The coarse separator and the further liquid separator may be arranged in a common casing or in a casing chamber formed by the casing. In this case, the mixture stream, after leaving the coarse separator, rises upward in the casing against gravity toward the further liquid separator located there. Alternatively, however, the further liquid separator may be located at a height below the outlet of the mixture stream leaving the coarse separator in the direction of gravity. In this case, the liquid separation system has a mixture stream guide that ensures that at least a predetermined portion of the mixture stream flows against gravity for feeding to the further liquid separator. The mixture flow guide may be a dividing wall, in which case the coarse separator is arranged on one side of the dividing wall and the further liquid separator is arranged on the other side of the dividing wall. The dividing wall has a perforation arranged above the mixture flow outlet in the direction of gravity for guiding the mixture flow through it. However, the further liquid separator may also be arranged in a housing chamber separate from the coarse separator, in which case the mixture flow is supplied to the further liquid separator via a mixture flow channel. The mixture flow channel has a mixture flow channel inlet through which the mixture flow from the coarse separator can enter, in which case the mixture flow channel inlet is arranged above the mixture flow outlet from the coarse separator in the direction of gravity. Alternatively or additionally, the mixture flow channel may have at least one section through which the mixture flow is guided against gravity.

[0041] Gravity-based liquid separation is assisted by the mixture flow leaving the coarse separator with at least a vertical flow portion, in particular a flow portion directed in the direction of gravity, and / or by the mixture flow being fed to a further liquid separator with a flow direction that is counter to gravity in at least a certain section.

[0042] In one configuration, the liquid separation system has a liquid pan and a further liquid separator, in particular a fine separator, is located on the opposite side of the liquid pan in the direction of gravity.

[0043] In other words, the separate liquid separator is disposed above the liquid pan in the direction of gravity, so that the mixture flow rising against gravity toward the separate liquid separator further separates the liquid into the liquid pan.

[0044] In one configuration, the liquid separation system includes a casing that forms the separating surface of the coarse separator.

[0045] Therefore, the casing of the liquid separation system can be configured to eliminate additional elements for forming a coarse separator. For example, one casing section can be concavely curved from the mixture supply outlet to the other liquid separator in a direction parallel to the liquid level in the liquid pan. In this case, if the mixture flow is directed tangentially from the mixture supply outlet along the concavely curved casing section to the other liquid separator, parallel to the liquid level, the liquid can be separated from the mixture flow through this section. In this case, it may be advantageous if the separation surface formed by this casing section is inclined toward the liquid pan. However, the casing or casing section can also mimic each of the other separation surfaces described above.

[0046] In particular, the mixture supply is oriented so that the mixture flow is directed against the force of gravity.

[0047] For example, in the above-described configuration of the liquid separation system including a liquid pan and a separate liquid separator located on the opposite side of the liquid pan in the direction of gravity, the casing wall extending from the liquid pan to the separate liquid separator may be cylindrical. The mixture supply section may be arranged so that the air-liquid mixture in the area facing the liquid pan is inclined upward in the direction of gravity and impinges at a small impingement angle against the casing wall as a separation surface, and the mixture flow is guided tangentially along the cylindrical casing wall to the separate liquid separator. In other words, the mixture flow is guided spirally through the cylindrical casing wall against gravity to the separate liquid separator.

[0048] The invention will now be described in more detail by way of example with reference to the accompanying drawings, in which: FIG. [Brief explanation of the drawings]

[0049] [Figure 1] 1 is a schematic cross-sectional view of an exemplary prior art liquid separation system. [Figure 2] 1 is a schematic cross-sectional view of a liquid separation system according to an exemplary configuration including a liquid separation device according to a first exemplary embodiment of the present invention; [Figure 3a] 4 is a schematic cross-sectional view of a liquid separation device in a plane parallel to and passing through the longitudinal axis of a coarse separator according to a second exemplary embodiment of the present invention; FIG. [Figure 3b] 4 is a schematic cross-sectional view of a liquid separation device in a plane perpendicular to the longitudinal axis according to a second exemplary embodiment of the present invention; FIG. [Figure 4a] 10 is a schematic cross-sectional view of a liquid separation device in a plane parallel to and passing through the longitudinal axis of a coarse separator according to a third exemplary embodiment of the present invention. [Figure 4b] 10 is a schematic cross-sectional view of a liquid separation device in a plane perpendicular to the longitudinal axis according to a third exemplary embodiment of the present invention. [Figure 5a]10 is a schematic cross-sectional view of a liquid separation system according to an exemplary embodiment, including a liquid separation device according to a fourth exemplary embodiment of the present invention. [Figure 5b] FIG. 10 is a schematic cross-sectional view of an oil separation system in a plane parallel to the oil pan according to a fourth exemplary embodiment of the present invention.

[0050] FIG. 1 shows a schematic cross-sectional view of an oil separation system A as an example of an exemplary prior art liquid separation system. The oil separation system A has a casing B, the lower part of which forms an oil pan b. A fine separator is arranged in the upper part of the casing B, opposite the oil pan b in the direction of gravity. The fine separator E has a fine separator oil pan e in the area facing the oil pan b, where the oil separated in the fine separator E is collected. Residual air or at least one air-oil mixture containing a reduced proportion of oil is then discharged from the fine separator E via an air outlet line F. Oil from the oil pan b can be discharged from the casing A via an oil pan outlet line G1, and oil from the fine separator oil pan e can be discharged via a fine separator oil pan outlet line G2. The oil pan outlet line G1 and the fine separator oil pan outlet line G2 are combined into a common oil outlet line G.

[0051] Furthermore, a baffle plate D is arranged in the casing A as a coarse separator, which reduces the amount of oil contained in the air-oil mixture H before it is fed to the fine separator E. The baffle plate D is spaced apart from the level surface of the oil pan b and has a separation surface facing the oil pan b. The air-oil mixture H is introduced into the casing A via a pressure tube piece C as a mixture feeder. The pressure tube piece C is oriented so that the mixture flow Ha impinging on the baffle plate D impinges on the separation surface of the baffle plate D at an angle of 90° + / - 30° for coarse separation. For this purpose, the pressure tube piece C is guided through the oil pan b, and its outlet opening is oriented substantially parallel to the baffle plate D or its separation surface. Depending on the impingement angle and speed of the mixture flow Ha on the baffle plate D, various large oil droplets are produced, but also a particularly large number of small oil droplets. Relatively large oil droplets drip into the oil pan b due to their gravity, while relatively small droplets are distributed in the pressure chamber as secondary spray and can be further transported in the casing A by the mixture flow Hb downstream of the baffle plate D towards the fine separator E against gravity. Therefore, the mixture flow Hc supplied to the fine separator E may still contain a sufficient proportion of oil which, in particular due to the secondary spray, may affect the service life of the fine filter E and the efficiency of the compressor system.

[0052] To reduce secondary spray, FIG. 2 shows a schematic cross-sectional view of an oil separation system 1, an example of a liquid separation system with an exemplary configuration, including an oil separation device according to a first exemplary embodiment of the present invention. The oil separation system 1 according to the present invention differs from the prior art oil separation system A by the configuration of the oil separation device, which comprises a pressure pipe piece 20 as a mixture supply and a rough separator 30, arranged so that the air-oil mixture 70 impinges on the separation surface of the rough separator 30 at a relatively small impingement angle. The relatively small impingement angle, particularly in the range of 0° to 30°, in this case approximately 20°, allows the mixture flow 70a to be guided tangentially along the separation surface without being repelled from the separation surface. Through friction and braking, oil is separated from the mixture flow 70a and can drip into the oil pan 11 opposite the separation surface. Secondary spray is substantially minimized. The pressure pipe piece 20 is arranged in the side wall of the casing 10 of the separating device in the exemplary embodiment, not guided through the oil pan 11 but extending from it.

[0053] In other respects, the oil separation system 1 is comparable to the oil separation system A. As described above for the prior art, the oil separation system 1 includes a casing 10 forming an oil pan 11. The casing 10 further includes a fine separator 40 arranged opposite the oil pan 11, the fine separator having a fine separator oil pan 41. Oil from the oil pan 11 is discharged via an oil pan discharge line 61, and oil from the fine separator oil pan 41 is discharged via a fine separator oil pan discharge line 62; these lines are combined to form a single oil discharge line 60. After the mixture stream 70a flows tangentially along the separation surface, it is further distributed as a mixture stream 70b into the pressure chamber formed by the casing 10 and is supplied against gravity as a mixture stream 70c to the fine separator 40. The air, or at least one air-oil mixture having an oil content reduced by the fine separator 40 , is discharged from the fine separator 40 via an air outlet line 50 .

[0054] FIG. 3a shows a schematic cross-sectional view of an oil separation device in a plane parallel to and passing through the longitudinal axis L of a rough separator 30' according to a second exemplary embodiment of the present invention. The oil separation device comprises a pressure tube 20' and a rough separator 30'. The rough separator 30' is formed as a parabolic hollow body rotationally symmetrical about the longitudinal axis L or the axis of symmetry R, ​​which extends from an opening formed by its largest diameter to the reversal point of the parabolic extension along the axis of symmetry R. In other words, the rough separator 30' forms a dome-shaped body, and the reversal point of the parabolic extension corresponds to the dome apex. Thus, a concavely curved separation surface is formed by the inner surface of the rough separator 30'. At the mixture feed outlet, the pressure tube 20' protrudes through the opening of the rough separator 30' into the volume of the rough separator 30' formed by the separation surface. However, in an alternative embodiment, the pressure tube section 20' or the mixture feed outlet may be located outside the volume of the coarse separator 30' formed by the separation surface. The mixture feed outlet of the pressure tube section 20' is oriented toward the parabolic side of the coarse separator 30', so that the air-oil mixture 70 impinges on the separation surface at a relatively small impingement angle, in this case about 20°, between the separation surface and the impingement direction of the air-oil mixture 70, as viewed in the impingement direction. The mixture stream travels tangentially along the separation surface in the direction of the symmetry axis R or longitudinal axis L of the coarse separator 30' toward the dome tip or reversal point of the parabolic extension, is then redirected again by the opposing separation surface toward the opening, and is then again forced to exit the coarse separator 30' and be further guided as mixture stream 70b.

[0055] 2, the oil separation device according to FIG. 3a can be used alternatively or additionally to the pressure stub 20 and the coarse separator 30, with the opening of the coarse separator 30' facing towards the oil pan 11. Oil separated on the separation surface can therefore always drip into the oil pan 11. The pressure stub 20' is in this case oriented substantially towards the oil pan 11, so that it can be guided through the oil pan.

[0056] The pressure pipe 20' may be part of a casing block of an oil-lubricated screw compressor (not shown), which discharges the compressed air-oil mixture 70 from the screw compressor. The coarse separator 30' is in this case likewise part of this casing block or is correspondingly fixedly connected to the pressure pipe 20', or in an alternative embodiment, can be fixedly connected.

[0057] Complementary to FIG. 3a, FIG. 3b shows a schematic cross-sectional view of an oil separation device according to a second exemplary embodiment of the present invention, taken along a plane perpendicular to the longitudinal axis L or the axis of symmetry R. In other words, FIG. 3b shows a cross-sectional view of the oil separation device of FIG. 3a, viewed from above. The view originates from the dome tip side, i.e., toward the opening of the rough separator 30′. The introduction of the air-oil mixture 70 into the rough separator 30′ is represented by a circled dot, which corresponds to the flow direction out of the plane of the drawing. In this case, the air-oil mixture is directed toward the separation surface. The mixture flow 70a on the other side of the separation surface, again in the direction of the opening, is correspondingly represented by a circled cross, i.e., which corresponds to the flow direction into the plane of the drawing.

[0058] The pressure tube stub 20' is held in a positionally fixed connection to the rough separator 30' by three connecting webs 20a', 20b', and 20c' as connecting means. In alternative embodiments, the pressure tube stub 20' may be connected to the rough separator 30' by more or fewer connecting webs or by other connecting means. In the illustrated embodiment, the pressure tube stub 20', connecting webs 20a'-20c', and rough separator 30' are formed as integrally cast components. Alternatively, welded structures or other integral constructions can be used. In further alternative embodiments, each connecting web 20a'-20c' may be threadedly or otherwise removably connected to the rough separator 30' and pressure tube stub 20', respectively, allowing the relative position between the pressure tube stub 20' and the rough separator 30' to be adjusted or adapted and / or individual components to be replaced.

[0059] FIG. 4a shows a schematic cross-section of an oil separation device in a plane parallel to and passing through the longitudinal axis L of a rough separator 30″ according to a third exemplary embodiment of the invention. The third embodiment of the oil separation device differs from the second embodiment of the oil separation device by the arrangement of the pressure tube 20″ relative to the separation surface formed by the rough separator 30″. As in the second embodiment of the oil separation device, the rough separator 30″ is formed as a parabolic hollow body that is rotationally symmetrical about the longitudinal axis L or the axis of symmetry R, ​​and which extends from the opening formed by the largest diameter to the reversal point of the parabolic extension along the axis of symmetry. In other words, the rough separator 30″ also forms a dome-shaped body, the reversal point of the parabolic extension corresponding to the dome apex. The inner surface of the rough separator 30″ therefore forms a concavely curved separation surface. The pressure tube piece 20'' is arranged in the area of ​​the coarse separator 30'' facing the dome tip, and the mixture feed outlet is inclined towards the opening of the coarse separator 30''. The mixture feed outlet is further oriented towards the separation surface so that the air-oil mixture is guided towards the separation surface in the circumferential direction of the diameter of the coarse separator 30'' at an impact angle of approximately 20°. The mixture flow 70a is therefore guided tangentially in the circumferential direction in a spiral towards the opening of the coarse separator 30''.

[0060] 4b shows a schematic cross-section of an oil separation device according to a third exemplary embodiment of the invention in a plane perpendicular to the longitudinal axis L or the axis of symmetry R. This figure again shows the circular trajectory through which the mixture flow 70a flows, spiraling towards the opening of the coarse separator 30″.

[0061] 2, the oil separation device according to FIGS. 4a and 4b can be used as an alternative or supplement to the pressure stub 20 and the coarse separator 30, with the opening of the coarse separator 30'' facing towards the oil pan 11. Oil separated on the separation surface can therefore drip into the oil pan 11 whenever possible. With respect to the second embodiment shown in FIGS. 3a and 3b, it is further possible to convert the second embodiment into a third embodiment or to operate it in accordance with the third embodiment by a different arrangement of the pressure stub 20' or by providing an additional pressure stub 20''. In this case, the pressure stub 20' can be repositioned accordingly, so that in this case the pressure stub 20' is no longer integrally connected to the coarse separator 30' but can still be fixedly connected to it. Similarly, the oil separation device according to the third embodiment can be integrated into the oil separation device of the second embodiment or operated accordingly. As long as two pressure tube sections 20′ and 20″ are provided in the respective arrangement, for example, the air-oil mixture 70 can be introduced via the pressure tube section 20′ and / or via the pressure tube section 20″. The simultaneous introduction via both pressure tube sections 20′ and 20″ may depend, inter alia, on the flow velocity and the probability and effect of vortex generation.

[0062] FIG. 5a shows a schematic cross-sectional view of an exemplary embodiment of an oil separation system 1′ with an oil separation device according to a fourth exemplary embodiment of the present invention. The oil separation system 1′ differs from the oil separation system 1 essentially in that the coarse separator 30′″ is not arranged inside the casing 10′″ of the oil separation system 1′, but is formed by the casing 10′″ itself. For this purpose, the casing 10′″ has at least one casing section as a separation surface. In the illustrated embodiment, the separation surface is formed by a lateral inner surface of the casing 10′″ extending from the oil pan 11 in the direction against gravity. The pressure tube end 20′″ is arranged laterally above the oil pan 11 in the direction of gravity in this case. The mixture supply outlet is provided facing away from the oil pan 11. With this arrangement, the mixture flow 70a is guided tangentially in the circumferential direction of the inner lateral surface of the casing 10''', spirally against gravity, towards the fine separator 40, which is arranged in the upper casing region opposite the oil pan 11 in the direction of gravity.

[0063] FIG. 5b shows a schematic cross-sectional view of an oil separation system 1′ according to a fourth exemplary embodiment of the present invention in a plane parallel to the oil pan 11. In other words, FIG. 5b shows a view of the oil separation system 1′ according to FIG. 5a from above, with the line of sight toward the oil pan 11. In this case, the cutting plane is between the oil pan 11 and the fine separator 40. According to the fourth embodiment, the inner lateral surface of the casing 10′″ forms a cylinder. The cylindrical surface forms the separation surface of the resulting coarse separator 30′″. As mentioned above, the mixture supply outlet is slightly inclined toward the fine separator 40, so that the mixture flow 70a is also directed toward the fine separator 40 at a predetermined flow rate. In other words, each arrow representing the mixture flow 70a is located closer to the fine separator 40 than the previous arrow in the direction of gravity, i.e., in the height direction in proper use, starting from the first arrow downstream of the pressure tube piece 20′″ and proceeding clockwise.

[0064] The present invention is not limited to the described embodiments. Although the above-described embodiments describe an oil separation device, a coarse separator, and an oil separation system for oil separation, the liquid separation device, the corresponding coarse separator, and the liquid separation system according to the present invention are not limited to the use of oil or oil-containing liquids. For example, other liquids used alternatively or additionally for cooling and / or lubrication in a compressor system can also be separated. The separation device may also have multiple mixture feeds and / or multiple mixture feed outlets to selectively or simultaneously direct multiple mixture streams toward the separation surface. [Explanation of symbols]

[0065] 1,1' Oil Separation System (Liquid Separation System) 10 Casing 11 Oil pan (fluid pan) 20, 20', 20'', 20'''' Pressure pipe section (mixture supply section) 20a', 20b', 20c' Connecting web (connecting means) 30,30',30'',30''' Coarse separator 40 Fine separator (another liquid separator) 41 Fine separator oil pan (fine separator liquid pan) 50 Air outlet pipe 60 Oil outlet pipe (liquid outlet pipe) 61 Oil pan outlet line (liquid pan outlet line) 62 Fine separator oil pan outlet line (fine separator liquid pan outlet line) 70 Air-oil mixture (air-liquid mixture) 70a Mixed flow (crude separator) 70b Mixture flow (casing) 70c Mixed flow (fine separator) A Oil separation system (liquid separation system) B. Casing b Oil pan (fluid pan) D Pressure pipe piece (mixture supply section) D Baffle plate (coarse separator) E Fine separator e Fine separator oil pan (fine separator liquid pan) F Air outlet duct G Oil outlet line (liquid outlet line) G1 Oil pan outlet line (liquid pan outlet line) G2 Fine separator oil pan outlet line (fine separator liquid pan outlet line) H Air-oil mixture (air-liquid mixture) Ha Mixed flow (crude separator) Hb mixture flow (casing) Hc mixed flow (fine separator) L Longitudinal axis R symmetry axis

Claims

1. 1. A liquid separation device for a compressor system, comprising: a coarse separator (30, 30', 30'', 30''') having at least one separating surface; at least one mixture supply (20, 20', 20'', 20''') configured to supply an air-liquid mixture (70) to said separation surface; Equipped with the mixture supply section (20, 20', 20'', 20''') is formed with a mixture supply outlet facing the separation surface, the mixture supply outlet being positioned relative to the separation surface of the coarse separator (30, 30', 30'', 30''') such that a mixture flow (70a) contacting the separation surface is guided substantially tangentially over at least one section of the separation surface, a separation surface of the coarse separator (30', 30", 30'") facing the mixture supply section (20', 20", 20'") is formed to be substantially concavely curved at least in a cross-sectional section through which the mixture flow (70a) must flow, and the mixture supply section (20', 20", 20'") is arranged so that the mixture flow (70a) is guided substantially along the concave curvature at least in a predetermined section; The separation surface of the coarse separator (30') is formed in a parabolic or dome shape, and the mixture supply section (20') is arranged so that the mixture flow (70a) is guided from at least one side of the separation surface to the other side of the separation surface via a parabolic turning point or a dome arc.

2. 2. The liquid separation device of claim 1, wherein the cross section of the mixture feed outlet facing the separation surface is equal to or less than the exit area of ​​the mixture stream (70a) from the rough separator (30, 30', 30'', 30''').

3. 3. The liquid separating device according to claim 1, wherein the mixture supply (20', 20'', 20''') is fixedly connected or connectable to the coarse separator (30', 30'', 30''').

4. 4. The liquid separating device according to claim 3, wherein a connecting means is used to connect the mixture supply (20', 20'', 20''') to the coarse separator (30', 30'', 30''').

5. 4. The liquid separating device according to claim 3, wherein the relative positions of the mixture supply (20', 20'', 20''') and the coarse separator (30', 30'', 30''') are adaptable via an adapting device.

6. 4. The liquid separating device according to claim 3, wherein the connection between the mixture supply (20', 20'', 20''') and the coarse separator (30', 30'', 30''') is detachable.

7. 4. The liquid separating device according to claim 3, wherein the mixture supply section (20', 20'', 20''') and the coarse separator (30', 30'', 30''') are integrally formed.

8. 3. The liquid separation device according to claim 1, wherein the separation surface is curved such that the mixture flow (70a) can change direction by at least 90° from the flow direction at the mixture supply (20', 20'', 20''') until it leaves the rough separator (30, 30', 30'', 30''').

9. 3. A liquid separating device according to claim 1 or 2, wherein the separating surface is at least partially contoured and / or has a friction-enhancing surface.

10. 10. A liquid separation system (1, 1′) comprising a liquid separation device according to claim 1 and a rough separator (30, 30′, 30″, 30′″), wherein the cross section of the mixture supply outlet facing the separation surface is equal to or smaller than the exit area of ​​the mixture stream (70a) from the rough separator (30, 30′, 30″, 30′″), thereby allowing the mixture stream (70a) to be introduced tangentially, and wherein the liquid separation device is configured such that the mixture stream (70a) is introduced into the liquid separation system (1) in a manner such that: the liquid separation system (1, 1') is arranged to flow out of the coarse separator (30, 30', 30'') with at least a certain percentage of the flow being in a vertical direction, and / or the liquid separation system (1, 1') comprises a further liquid separator (40) arranged such that the mixture stream (70a, 70b, 70c) can be fed to the further liquid separator (40) in a flow direction against gravity, at least in a predetermined section.

11. The liquid separation system (1, 1') according to claim 10, wherein the liquid separation system (1, 1') has a liquid pan (11), and the further liquid separator (40) is arranged on the opposite side of the liquid pan (11) in the direction of gravity.

12. The liquid separation system (1') according to claim 10, characterized in that it comprises a casing (10''') forming a separation surface of the coarse separator (30''').

13. 13. The liquid separation system (1') of claim 12, wherein the mixture supply (20''') is oriented such that the mixture flow (70a) is directed against gravity.

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