Centrifugal separator
By designing two parallel flow paths in the gas-liquid centrifugal separator, the problem of high pressure drop at the atmospheric liquid flow rate is solved, and the compact size and efficient separation effect is achieved, ensuring the low back pressure and high efficiency of the internal combustion engine Separation.
Patent Information
- Application Number
- CN202380039116.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2022-05-09
- Filing Date
- 2023-04-21
- Publication Date
- 2024-12-17
AI Technical Summary
Existing gas-liquid centrifugal separators face high pressure drop problems when dealing with atmospheric liquid flow rates, resulting in an increase in the size of the equipment, and the separated liquid phase and gas phase are easily remixed, affecting the separation efficiency.
Design a centrifugal separator including two parallel flow paths to reduce pressure drop by dividing the gas-liquid mixture flow between two separation aids and achieve low pressure drop and high efficiency through the same size separation aid and flow path design. Separation.
The ability to handle the atmospheric liquid flow rate within a compact size is achieved, the pressure drop of the gas-liquid mixture when passing through the separator is reduced, the crankcase ventilation of the internal combustion engine is ensured, and the separation efficiency and the compactness of the equipment is improved.
Smart Images
Figure CN119156258A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to a centrifugal separator for separating a gas-liquid mixture into a gas phase and a liquid phase. Background Art
[0002] Centrifugal separators can be designed to separate a gas-liquid mixture into a gas phase and a liquid phase. The liquid phase may include solid particles. An example of such a gas-liquid separation is the removal of oil and other particles from crankcase gases.
[0003] Crankcase gases are exhausted from the crankcase of an internal combustion engine (ICE). Instead of being discharged to the atmosphere in untreated form, crankcase gases can be treated in an environmentally friendly manner. For some types of combustion engines, it is even required by law to treat crankcase gases in an environmentally friendly manner.
[0004] The crankcase gases may include, among other things, blow-by gases, oil, other liquid hydrocarbons, soot and other solid combustion residues. In order to properly treat the crankcase gases, the gases are separated from the oil, soot and other residues. The separated gases may be directed to the air intake of the combustion engine or discharged to the atmosphere. The oil may optionally be directed back to the oil sump of the combustion engine via an oil filter to remove soot and other solid residues from the oil.
[0005] A centrifugal separator can be used to process crankcase gas. The crankcase gas is introduced into the rotor of the centrifugal separator, and the heavy components of the crankcase gas (such as oil and soot) are separated from the clean gas phase as a liquid phase. The liquid phase is drawn from the centrifugal separator via a liquid outlet. The gas phase is drawn from the centrifugal separator via a gas outlet and can be directed to the intake of the ICE.
[0006] A common structural feature of centrifugal separators configured for gas-liquid separation is that a rotor including a separation aid (e.g. in the form of a separation disc) is arranged in a fixed housing. That is, the rotor rotates in a fixed separation space within the housing. The separation of gas and liquid can be in the form of a co-current separation, i.e. the gas and liquid both move through the rotor in the same direction when being separated. Alternatively, the separation of gas and liquid can be in the form of a counter-current separation, i.e. the gas and liquid move through the rotor in opposite directions when being separated.
[0007] The construction of the liquid-liquid separator or liquid-solid separator differs from the above-discussed feature of providing a fixed separation space. That is, in the liquid-liquid separator or liquid-solid separator, the rotor also defines the separation space. That is, the separation space rotates together with the separation aid. Liquid-liquid separation and liquid-solid separation can only be carried out efficiently in countercurrent separation.
[0008] WO2019 / 175079 discloses a centrifugal separator for separating oil droplets from crankcase ventilation gas. The rotor includes a shaft with disks, which are arranged one by one to form a disk stack. Adjacent disks define a flow gap between them. The rotor is arranged in a housing having a raw gas inlet, a pure gas outlet and an oil outlet. The disk stack is divided into a first disk stack part and a second disk stack part along its axial direction. The gas flows through the two disk stack parts sequentially. The raw gas inlet leads to the radially inner region of the first disk stack part, so that the gas flows through it in a radially outward direction during operation. The gas flows through the second disk stack part in a radially inward direction. That is, co-current separation is performed in the first disk stack part, and counter-current separation is performed in the second disk stack part. This arrangement of two disk stack parts is provided to improve the separation of oil from gas.
[0009] In many countries, legislation relating to the emission of crankcase gases from land-based vehicles is very strict. Gas-liquid centrifugal separators are therefore a standard component of many ICEs for land-based vehicles.
[0010] For ICEs that are larger than those used for land-based vehicles, a larger gas-liquid centrifugal separator is required to handle the correspondingly larger crankcase gas flow rate.
[0011] More generally, the greater the flow rate of the gas-liquid mixture to be separated, the greater the separation capacity required of the separation device for separating the gas-liquid mixture. Summary of the invention
[0012] A gas-liquid centrifugal separator is designed for a specific flow rate of a gas-liquid mixture, and includes a rotor having a separation aid, such as a stack of separation discs. Typically, the gas-liquid mixture is introduced at the center of the rotor and separated as it flows radially outward through the separation aid. The rotor is arranged in a housing defining a separation space.
[0013] The scale-up of centrifugal separators for separating gas-liquid mixtures poses particular problems.
[0014] The centrifugal separator for separating the gas-liquid mixture may also be used as a pump for pumping the gas-liquid mixture through a pipe leading the gas-liquid mixture to the centrifugal separator.
[0015] If for example the gas-liquid mixture is crankcase gas from an ICE, the crankcase ventilation of the ICE should not be limited by the high backpressure from the crankcase gas cleaning device. Long pipes will result in high pressure drops. Therefore, the centrifugal separator used as a pump will compensate for the pressure drop in the pipe leading to the centrifugal separator.
[0016] Gas flow rates higher than the design flow rate of the centrifugal separator will result in an undesirably high pressure drop in the gas-liquid separator, primarily due to the size of the central gas passage in the rotor and the size of the space between the rotor and the casing.
[0017] In order to maintain the appropriate pump capacity of the centrifugal separator designed for higher flow rate, this pressure drop should be reduced or eliminated. The size of the gas-liquid centrifugal separator needs to be redesigned to reduce or eliminate the pressure drop. This redesign requires increasing the inner diameter of the rotor for gas-liquid mixture. If the outer diameter of the rotor is not increased, this will reduce the separation capacity. Therefore, a rotor with a larger diameter and / or a longer rotor will be required. In addition, this redesign requires a larger housing diameter to increase the distance between the rotor and the housing to reduce or eliminate the pressure drop. The distance of this increase between the rotor and the housing increases the risk of the separated liquid phase and the clean gas phase remixing before the separated liquid phase is deposited on the inner surface of the housing. Therefore, the redesign for the increased flow rate and low pressure drop will at least cause the housing diameter of the centrifugal separator to be larger.
[0018] It would be advantageous to achieve a centrifugal separator that is generally formed to handle atmospheric liquid flow rates. In particular, it would be desirable to enable a gas-liquid centrifugal separator to be designed to handle atmospheric liquid flow rates within a compact size, at least in a radial direction of the axis of the centrifugal separator. In order to better address one or more of these concerns, a centrifugal separator having the features defined in the independent claims is provided.
[0019] According to one aspect of the present invention, a centrifugal separator for separating a gas-liquid mixture into a gas phase and a liquid phase is provided. The centrifugal separator comprises: a housing, a first separation space at least partially defined by the housing, a first separation aid for separating a liquid phase from a gas phase arranged in the first separation space, a drive arrangement configured to rotate the first separation aid, an inlet for the gas-liquid mixture, a gas outlet for the separated gas phase, a liquid outlet for the separated liquid phase, a second separation space at least partially defined by the housing, and a second separation aid for separating a liquid phase from a gas phase arranged in the second separation space. The drive arrangement is configured to rotate the second separation aid. A first channel connects the inlet with the first separation space, and a second channel connects the inlet with the second separation space. The first separation aid and the second separation aid are also arranged along a common axis.
[0020] The same drive arrangement may be used to rotate both the first separation aid and the second separation aid.As an example, the same drive arrangement may be used to rotate both the first separation aid and the second separation aid along a common rotation axis.
[0021] The first separation aid and the second separation aid may be formed successively to one another along the same common axis of rotation.
[0022] Since the housing of the centrifugal separator defines the first and second separation spaces and comprises the first and second separation aids arranged in the first and second separation spaces respectively, and since the first channel connects the inlet with the first separation space and the second channel connects the inlet with the second separation space, the centrifugal separator is designed to distribute the inflowing gas-liquid mixture between two independent parts of the centrifugal separator. Therefore, only a part of the total flow rate of the gas-liquid mixture will flow through each of the first and second separation spaces and the separation aids. Therefore, within a centrifugal separator of compact size, in particular in the radial direction of the respective first and second separation aids, provisions are provided for a relatively low total pressure drop.
[0023] More specifically, the inventors have realized that by dividing the gas-liquid mixture flow between two parallel flow paths through the centrifugal separator, the pressure drop affecting the gas-liquid mixture and the separated gas phase when it passes through the separator is reduced. More specifically, the flow rate in each flow path is reduced to, for example, half of the inflow flow rate. Since the pressure drop of the gas / gas phase is roughly related to the square of the turbulent gas velocity (i.e., the ratio of flow rate to cross-sectional area) according to the basic pipe fluid flow formula, it is seen that doubling the cross-section by using two separation aids can produce a four-fold pressure drop reduction. Therefore, the centrifugal separator can have a compact size while providing a low pressure drop at the nominal flow rate through the centrifugal separator.
[0024] For example, a low pressure drop may be advantageous when the centrifugal separator is used to separate a liquid phase from a gas-liquid mixture in the form of crankcase gas.A low pressure drop ensures a low backpressure for crankcase ventilation of the associated internal combustion engine (ICE).
[0025] Thus, the centrifugal separator may be arranged for cleaning crankcase gases from an ICE. Such an ICE may be, for example, a large diesel engine. Such a large diesel engine may be configured to propel a marine vessel or to drive a generator in a power plant.
[0026] Crankcase gases (also known as blow-by gases) may be exhausted from the crankcase of the ICE via a crankcase ventilation system. A centrifugal separator may form part of the crankcase ventilation system.
[0027] Crankcase gases are the result of high pressure within the cylinders of the ICE forcing some of the combustion gases and liquid and solid residues past the piston rings and down into the crankcase of the ICE. If not vented, the increased pressure within the crankcase may cause engine oil to leak out of the ICE, and the liquid and solid residues may contaminate and / or dilute the engine oil.
[0028] Thus, the gas-liquid mixture may be crankcase gas, and the centrifugal separator may be configured to separate heavy components of the crankcase gas, such as oil, other liquid hydrocarbons, soot and other solid combustion residues, from the crankcase gas as a liquid phase.
[0029] However, the centrifugal separator may alternatively be used in other gas-liquid separation applications, such as metal cutting coolant mist separation.
[0030] In operation of the centrifugal separator, the gas-liquid mixture enters the first and second separation spaces and the first and second separation aids via the inlet and the first and second channels.
[0031] Therefore, during use of the centrifugal separator, the gas-liquid mixture flow through the inlet is divided into two parallel flow paths within the centrifugal separator, namely a first flow path entering the first separation aid and the first separation space, and a second flow path entering the second separation aid and the second separation space.
[0032] The first separation aid and the first separation space may have substantially the same size and structure as the second separation aid and the second separation space. In this way, the two parallel flow paths may provide substantially similar resistances, and the first flow path and the second flow path will have the same flow rate.
[0033] The gas-liquid mixture can enter the corresponding separation aid from the central part of the corresponding separation aid. When the first separation aid and the second separation aid rotate, heavy components (such as liquids and optionally particles) are deposited on the radially inward facing surface and / or forward facing surface (in the direction of rotation) of the separation aid. The heavy components are therefore separated and form droplets that flow along these surfaces. At the outer periphery of the corresponding separation aid, the droplets are pushed against the inner wall surface that defines the corresponding separation space. The droplets form a separated liquid phase, and the separated liquid phase flows along the inner wall surface to the liquid outlet, where it is derived from the centrifugal separator. The clean gas (i.e., the gas phase) is removed from all or substantially all of the heavy components of the gas-liquid mixture and is derived from the centrifugal separator via the gas outlet.
[0034] Each of the first separation aid and the second separation aid has a rotation axis, and the corresponding separation aid rotates around the rotation axis. The axial direction extends along each rotation axis, and the radial direction extends perpendicular to each rotation axis. The central part of the separation aid is closer to its rotation axis than the peripheral part of the separation aid. The circumferential direction extends around the rotation axis and / or around the separation aid.
[0035] Each of the first and second separation aids forms a rotor or a major part of a rotor driven by the drive arrangement.
[0036] The individual separation aids may be rotationally symmetrical.
[0037] The first separation aid and the second separation aid ensure consistent separation of the liquid from the gas-liquid mixture. More specifically, the separation aid comprises a plurality of separation members that improve the separation of the heavy component from the gas-liquid mixture. Such separation members may take the form of, for example, axially extending blades that point radially from the rotor shaft or stacked frustoconical separation disks. When the rotor rotates, the heavy component is pressed against the surface of the separation member (on which it forms droplets) while traveling along the separation member toward the outer periphery of the corresponding separation aid.
[0038] The housing of the centrifugal separator is fixed relative to, for example, an ICE whose crankcase gases are to be purified by the centrifugal separator.
[0039] The first separation aid and the second separation aid are arranged to rotate relative to the housing during use of the centrifugal separator. Therefore, during use of the centrifugal separator, the housing is fixed relative to the first separation aid and the second separation aid. Therefore, during use of the centrifugal separator, the first separation space and the second separation space are also fixed relative to the housing.
[0040] During use of the centrifugal separator, the rotating first and second separation aids will accelerate the gas-liquid mixture in the circumferential direction. The separated liquid phase and gas phase will rotate with the separation aids. In the first and second separation spaces between the respective separation aids and the inner wall surface, the gas phase will continue to flow in the circumferential direction at different degrees while flowing toward the gas outlet.
[0041] According to an embodiment, the centrifugal separator may be configured to separate the gas-liquid mixture into a gas phase and a liquid phase simultaneously. That is, the separated phases travel in the same direction, radially outwardly through the first separation aid and the second separation aid, respectively.
[0042] More specifically, the centrifugal separator may be configured to simultaneously separate the gas-liquid mixture into a gas phase and a liquid phase in each of the first separation aid and the second separation aid.
[0043] As discussed above, the liquid phase can travel from the central portion of the respective separation aid to its periphery. The same can be said for the other separated phase, i.e., the gas phase. The gas phase can travel from the central portion of the respective separation aid to its periphery while the heavy components are separated from the gas.
[0044] According to an embodiment, the inlet may be arranged between the first separation space and the second separation space. In this way, the gas-liquid mixture may be introduced into the centrifugal separator in the center. Therefore, the first channel and the second channel leading to the first separation space and the second separation space may have substantially the same length, which promotes an equal distribution of the gas-liquid mixture between the first separation space and the second separation space.
[0045] According to an embodiment, the first channel and the second channel may extend from the inlet in opposite directions. In this way, the gas-liquid mixture may be guided from the inlet in opposite directions into the respective first and second separation aids and the separation space.
[0046] According to an embodiment, radially outer portions of the first and second separation spaces may be arranged in fluid communication with the gas outlet. In this way, the gas outlet may be provided as a common gas outlet for both the first and second separation spaces.
[0047] According to an embodiment, radially outer portions of the first and second separation spaces may be arranged in fluid communication with the liquid outlet. In this way, the liquid outlet may be provided as a common liquid outlet for both the first and second separation spaces.
[0048] According to an embodiment, the first separation aid and the second separation aid may be arranged along a common axis. In this way, the first separation aid and the second separation aid may be arranged along a common axis. Therefore, the resources discussed above for compact dimensions in the radial direction of the centrifugal separator can be used to provide a centrifugal separator with a relatively small diameter.
[0049] According to an embodiment, in the use position of the centrifugal separator, the common axis can extend substantially horizontally. In this way, gravity will affect the flow of the gas-liquid mixture and the separated phases in the first separation space and the second separation space in an equal manner. Therefore, the flow conditions in the first separation space and the second separation space can be substantially similar.
[0050] According to an embodiment, the drive arrangement may include a rotor shaft extending along a common axis through the first separation space and the second separation space. The first separation aid and the second separation aid may be connected to the rotor shaft. In this way, the first separation aid and the second separation aid may be conveniently rotated via the common shaft and thus via a common drive unit connected to the rotor shaft.
[0051] Further features of, and advantages with, the present invention will become apparent when studying the appended claims and the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS
[0052] Various aspects and / or embodiments of the present invention, including specific features and advantages thereof, will be readily understood from the example embodiments discussed in the following detailed description and accompanying drawings, in which:
[0053] Figure 1 Show
[0054] Figure 1 A centrifugal separator according to an embodiment is schematically shown, and
[0055] Figure 2a and 2b A cross section of a centrifugal separator according to an embodiment is schematically shown. DETAILED DESCRIPTION
[0056] Aspects and / or embodiments of the present invention will now be described more fully. Like numbers always represent like elements. For the sake of brevity and / or clarity, well-known functions or structures will not necessarily be described in detail.
[0057] Figure 1 A centrifugal separator 2 according to an embodiment is schematically shown.
[0058] The centrifugal separator 2 is configured to separate the gas-liquid mixture into a gas phase and a liquid phase. The gas-liquid mixture may be crankcase gas from an internal combustion engine, or a gas-liquid mixture from metal cutting using a cooling liquid.
[0059] The centrifugal separator 2 comprises a housing 4 which at least partially delimits a first separation space and a second separation space therein. A first separation aid is arranged in the first separation space and a second separation aid is arranged in the second separation space. The housing 4 may be formed by one or more components.
[0060] The centrifugal separator 2 comprises a drive arrangement 7 which is configured to rotate the first and second separation aids about a common axis 9 .
[0061] In the embodiment shown, the drive arrangement 7 comprises a drive unit in the form of an electric motor configured to rotate the first and second separation aids. In an alternative embodiment, the drive arrangement may comprise two separate electric motors, one for rotating each of the first and second separation aids around a common axis or separate axes.
[0062] As an alternative to one or two electric motors, the drive arrangement may comprise one or two drive units including pneumatic motors, hydraulic motors, turbine wheels, gears, pulleys, belt drives or the like.
[0063] The centrifugal separator 2 further comprises an inlet 16 for the gas-liquid mixture, a gas outlet 18 for the separated gas phase, and a liquid outlet 20 for the separated liquid phase.
[0064] Figure 2a and 2bA cross section through a centrifugal separator 2 according to an embodiment is schematically shown. The cross sections extend perpendicularly to one another. In the use position of the centrifugal separator 2, Figure 2a The cross section of extends in a horizontal plane, and Figure 2b The cross section extends in a vertical plane.
[0065] Likewise, the centrifugal separator 2 is configured to separate the gas-liquid mixture into a gas phase and a liquid phase. The centrifugal separator 2 may be similar to the one described above with reference to Figure 1 The centrifugal separator discussed is 2. Likewise, the gas-liquid mixture may be crankcase gases from an internal combustion engine or mist from metal cutting using a cooling liquid.
[0066] Likewise, the centrifugal separator 2 includes a shell 4, a first separation space 6 at least partially defined by the shell 4, a first separation aid 10 for separating a liquid phase from a gas phase arranged in the first separation space 6, a second separation space 22 at least partially defined by the shell 4, and a second separation aid 24 for separating a liquid phase from a gas phase arranged in the second separation space 22.
[0067] The housing 4 may be formed of one or more parts. For example, the housing 4 may include a first circumferentially extending inner wall surface 34 that partially defines the first separation space 6. Similarly, the housing 4 may include a second circumferentially extending inner wall surface 36 that partially defines the second separation space 22.
[0068] More specifically, the housing 4 may include liquid phase receiving circumferential inner wall surfaces 34, 36. The circumferential inner wall surfaces 34, 36 are circumferential in that they extend circumferentially around the respective first separation space 6 and second separation space 22. The inner wall surfaces 34, 36 are configured to receive droplets of the separated liquid phase thereon and are therefore liquid phase receiving wall surfaces.
[0069] In other words, the circumferentially extending inner surfaces 34 , 36 of the housing 4 may form receiving surfaces for the separated liquid phase in the first separation space 6 and the second separation space 22 .
[0070] In the embodiment shown, in the axial direction, each of the first separation space 6 and the second separation space 22 is also delimited by an axial end disk 5, 5' connected to the rotor shaft 8 of the centrifugal separator 2. Alternatively or additionally, the first separation space 6 and the second separation space 22 may be delimited in the respective axial direction by parts of the housing 4.
[0071] The centrifugal separator 2 further comprises a drive arrangement 7 which is configured to rotate the first separation aid 10 and the second separation aid 24 .
[0072] The drive arrangement 7 may comprise at least a first drive unit 11 which is configured to rotate the first separation aid 10 .
[0073] In the illustrated embodiment, the drive arrangement 7 is configured to rotate the first 10 and the second 24 separation aids about a common axis 9. Thus, the first drive unit 11 may be configured to rotate the first 10 and the second 24 separation aids.
[0074] In the illustrated embodiment, the drive unit 11 is an electric motor configured to rotate the rotor shaft 8 , but the drive unit 11 may be of any alternative type as discussed above.
[0075] Therefore, the first separation aid 10 and the second separation aid 22 are arranged along the common axis 9. Therefore, the first separation space 6 and the second separation space 22 are also aligned along the common axis 9. This can provide the dimensions of the first separation space 6 and the second separation space 22 to determine the outer dimensions of the centrifugal separator 2. Therefore, the centrifugal separator 2 can have a compact size along the common axis 9.
[0076] The drive arrangement 7 comprises a rotor shaft 8. The rotor shaft 8 extends through the first separation space 6 and the second separation space 22 along a common axis 9. A first separation aid 10 and a second separation aid 24 are connected to the rotor shaft 8.
[0077] The rotor shaft 8 may be journalled in the housing 4 in any suitable manner. In the embodiment shown, a bearing 13 is arranged at each end of the rotor shaft 8. The bearing 13 may be, for example, one or more of a ball bearing, a roller bearing or a plain bearing.
[0078] The centrifugal separator 2 further comprises an inlet 16 for the gas-liquid mixture and a gas outlet 18 for the separated gas phase (see Figure 2a ), and a liquid outlet 20 for the separated liquid phase (see Figure 2b ).
[0079] The first passage 26 connects the inlet 16 and the first separation space 6. The second passage 28 connects the inlet 16 and the second separation space 22.
[0080] Thus, during use of the centrifugal separator 2 , the flow of the gas-liquid mixture through the inlet 16 is split into two parallel flow paths within the centrifugal separator, one flow path along each of the first passage 26 and the second passage 28 .
[0081] Thus, upstream of the first separation space 6, it is arranged in fluid communication with the inlet 16 via the first channel 26. Downstream of the first separation space 6, it is arranged in fluid communication with the gas outlet 18 and the liquid outlet 20. Similarly, upstream of the second separation space 22, it is arranged in fluid communication with the inlet 16 via the second channel 28. Downstream of the second separation space 22, it is arranged in fluid communication with the gas outlet 18 and the liquid outlet 20.
[0082] More specifically, radially outer portions of the first 6 and second 22 separation spaces are arranged in fluid communication with the gas outlet 20. Furthermore, radially outer portions of the first 6 and second 22 separation spaces are arranged in fluid communication with the liquid outlet 18.
[0083] The first separation space 6 and the second separation space 22 have a common inlet 16 and a common outlet 18 , 20 .
[0084] The first passage 26 opens into a radially central portion of the first separation space 6 , and the second passage 28 opens into a radially central portion of the second separation space 22 .
[0085] Furthermore, the first passage 26 opens into a radially central portion of the first separation aid 10 , and the second passage 28 opens into a radially central portion of the second separation aid 24 .
[0086] Therefore, the centrifugal separator 2 is configured to separate the gas-liquid mixture into gas phase and liquid phase simultaneously. That is, the separated phases travel in the same direction, passing through the first separation aid 6 and the second separation aid 22 radially outward from the central portion of the respective first separation aid 6 and the second separation aid 22.
[0087] In the illustrated embodiment, the inlet 16 is arranged between the first separation space 6 and the second separation space 22. That is, the gas-liquid mixture can be introduced into the centrifugal separator 2 in the center.
[0088] In addition, the inlet 16 can be arranged to provide a flow direction of the gas-liquid mixture entering the centrifugal separator 2 perpendicular to the common axis 9. Therefore, the first channel 26 and the second channel 28 can have substantially the same size and can provide the same flow resistance to the gas-liquid mixture. This can promote an equal distribution of the gas-liquid mixture between the first separation space 6 and the second separation space 22.
[0089] As in the illustrated embodiment, the gas outlet 18 may also be arranged between the first separation space 6 and the second separation space 22. This may promote equal flow resistance in the first separation space 6 and the second separation space 22, which in turn may promote equal distribution of the gas-liquid mixture between the first separation space 6 and the second separation space 22.
[0090] The first passage 26 and the second passage 28 extend in opposite directions and perpendicular to the inlet 16 .
[0091] As in the illustrated embodiment, the gas outlet 18 may be arranged to provide a flow direction of the gas phase leaving the centrifugal separator 2 perpendicular to the common axis 9. Therefore, the flow paths of the gas phase from each of the first separation space 6 and the second separation space 22 may have substantially the same size and may provide the same flow resistance to the gas phase. This may promote an equal distribution of the gas-liquid mixture between the first separation space 6 and the second separation space 22.
[0092] In the use position of the centrifugal separator 2, the common axis 9 can extend essentially horizontally, such as Figure 2b In this way, gravity will affect the gas-liquid mixture and the separated phases flowing into, through and out of the first separation space 6 and the second separation space 22, respectively, in an equal manner.
[0093] In the use position of the centrifugal separator 2, the liquid outlet 20 can be arranged at the lower part of the centrifugal separator 2, such as Figure 2b In this way, the liquid phase separated in the first separation space 6 and the second separation space 22 can be conveyed at least partly by gravity towards the liquid outlet 20 and / or through the liquid outlet 20.
[0094] Figure 2a and 2b The arrows in FIG. 2 indicate the flow of the gas-liquid mixture, the gas phase and the liquid phase through the centrifugal separator 2 .
[0095] Each of the first and second separation aids 10, 24 may comprise a stack 30, 30' of separation discs 32, 32'. In this way, efficient separation of the gas-liquid mixture may be provided in each of the first and second separation aids 10, 24.
[0096] Each of the separation discs 32, 32' may have a truncated cone shape. A gap is formed between the separation discs 32, 32' in the respective stacks 30, 30', and the gas-liquid mixture is introduced into the gap from the central portion of the respective stacks 30, 30'.
[0097] As the respective stacks 30, 30' rotate, the gas-liquid mixture travels from the inner periphery to the outer periphery of the disks 32, 32' while being separated into a liquid phase and a gas phase. Figure 2a and 2b In FIG. 3 , only some of the separation discs 32 , 32 ′ are indicated.
[0098] Mentioned merely by way of example, each stack 30, 30' of separation discs 32, 32' may comprise more than 50 separation discs, such as up to 100 separation discs, up to 200 separation discs or more.
[0099] In the illustrated embodiment, the frustoconical separation discs 32, 32' are stacked with their larger diameter ends facing axially outwards in the respective stack 30, 30'. In alternative embodiments, the frustoconical separation discs may be stacked with their larger diameter ends facing axially inwards in the respective stack.
[0100] The housing 4 is arranged to be fixed relative to the first auxiliary object 10 and the second separation aid 24. That is, the first auxiliary object 10 and the second separation aid 24 are arranged to rotate relative to the housing 4.
[0101] Furthermore, the housing 4 may be fixed relative to a larger structure, such as an ICE, which generates the gas-liquid mixture to be separated in the centrifugal separator 2 .
[0102] It should be understood that the above content describes various example embodiments, and the present invention is limited only by the appended claims. Those skilled in the art will recognize that the example embodiments can be modified, and the different features of the example embodiments can be combined to produce embodiments other than those described herein, without departing from the scope of the present invention defined by the appended claims.
Claims
1. A centrifugal separator (2) for separating a gas-liquid mixture into a gas phase and a liquid phase, the centrifugal separator (2) comprising: Housing (4), a first separation space (6) which is at least partially delimited by the housing (4), a first separation aid (10) for separating the liquid phase from the gas phase, which is arranged in the first separation space (6), a drive arrangement (7) configured to rotate the first separation aid (10), an inlet (16) for the gas-liquid mixture, a gas outlet (18) for the separated gas phase, a liquid outlet (20) for the separated liquid phase, a second separation space (22) at least partially delimited by the housing (4), A second separation aid (24) for separating the liquid phase from the gas phase is arranged in the second separation space (22), wherein The drive arrangement (7) is configured to rotate the second separation aid (24), wherein A first channel (26) connects the inlet (16) with the first separation space (6), and wherein A second channel (28) connects the inlet (16) and the second separation space (22), And wherein the first separation aid (10) and the second separation aid (24) are arranged along a common axis (9).
2. The centrifugal separator according to claim 1, wherein: The inlet is arranged between the first separation space (6) and the second separation space (22).
3. The centrifugal separator according to claim 1 or 2, wherein: Radially outer portions of the first separation space (6) and the second separation space (22) are arranged in fluid communication with the gas outlet (20).
4. A centrifugal separator according to any one of the preceding claims, wherein: Radially outer portions of the first separation space (6) and the second separation space (22) are arranged in fluid communication with the liquid outlet (18).
5. A centrifugal separator according to any one of the preceding claims, wherein: In the use position of the centrifugal separator (2), the common axis (9) extends essentially horizontally.
6. The centrifugal separator according to claim 5, wherein: The drive arrangement (7) comprises a rotor shaft (8) which extends along the common axis (9) through the first separation space (6) and the second separation space (22), and wherein the first separation aid and the second separation aid are connected to the rotor shaft (8).
7. A centrifugal separator according to any one of claims 1 to 6, wherein: The inlet (16) is arranged to provide a flow direction of the gas-liquid mixture entering the centrifugal separator (2) perpendicular to the common axis (9).
8. A centrifugal separator according to any one of claims 1 to 7, wherein: The gas outlet (18) is arranged to provide a flow direction of the gas phase leaving the centrifugal separator (2) perpendicular to the common axis (9).
9. A centrifugal separator according to any one of the preceding claims, wherein: The drive arrangement (7) comprises at least a first drive unit (11) configured to rotate the first separation aid (10).
10. A centrifugal separator according to any one of the preceding claims, wherein: In the use position of the centrifugal separator (2), the liquid outlet (18) is arranged at the lower part of the centrifugal separator (2).
11. A centrifugal separator according to any one of the preceding claims, wherein: Each of the first separation aid (10) and the second separation aid (24) comprises a stack (30, 30') of separation discs (32, 32').
12. A centrifugal separator according to any one of the preceding claims, wherein: The first passage (26) opens into a radially central portion of the first separation space (6), and the second passage (28) opens into a radially central portion of the second separation space (22).
13. A centrifugal separator according to any one of the preceding claims, wherein: The centrifugal separator (2) is configured to simultaneously separate the gas-liquid mixture into the gas phase and the liquid phase.
14. A centrifugal separator according to any one of the preceding claims, wherein: The housing (4) is arranged to be fixed relative to the first separation aid (10) and the second separation aid (24).