separator

Abstract

A separator (2) for separating a first fluid from a gas is describes and comprises an inlet (4) for receiving a flow of gas containing a first fluid to be separated, a separation apparatus (6) for removing the first fluid from the flow of gas, a separated fluid bowl (8) for receiving the first fluid removed from the flow of gas and an outlet (10) for expelling the flow of gas. The inlet (4) is arranged to direct the flow of gas against the base (12) of the separated fluid bowl, the base (12) of the separated fluid bowl (8) being configured to separate the flow of gas into a peripheral gas flow around a periphery (14) of the separated fluid bowl (8) to then flow into the separation apparatus (6).

Description

[0001] SEPARATOR

[0002] FIELD OF THE INVENTION

[0003] 0001 The present disclosure relates to a separator for separating a first fluid from a gas, and relates particularly, but not exclusively to a water separator for use in a hydrogen fuel cell system.

[0004] 0002 It is desirable to remove water from compressed air in many systems and compressed air water separators are known for this purpose. One such application of water separators is in hydrogen fuel cell systems which use a solid polymer as an electrolyte and porous carbon electrodes containing a platinum or platinum alloy catalyst. Such fuel cells only require hydrogen and oxygen from the air to produce electrical power. Air, water and heat are by-products. In such systems, water separators are used to remove water from air being circulated through the system.

[0005] 0003 Known water separators can suffer from several drawbacks.

[0006] Firstly, due to the arrangement of gas inlets and outlets, water separators can take up a large amount of space in systems in which they are used. Secondly, water separators may be used in cold conditions where there is a risk that separated water might freeze. For this reason, electrical heaters are often used to prevent freezing of water in water separators.

[0007] 0004 JP2010144696 describes a filter-type separation device for separating a liquid from a gas, more particularly filtering oil from blow-by gases in internal combustion engines. An embodiment is disclosed having both an inlet and outlet on a longitudinal axis. Blow-by gases move into the separator through the inlet disposed on the longitudinal axis. The gas then passes through a filter medium which removes oil, the gas then flowing up through the longitudinal outlet. The removed oil flows downwardly through the filter and out via an annular drain. In an alternative embodiment, the inlet is arranged as an annulus on the outside of the apparatus, the oil draining through an oil outlet on the longitudinal axis. The means of storage of oil is separate from the apparatus.

[0008] 0005 CN109098952B discloses an oil separator having co-axial inlets and outlets. Air moves into the axial outlet and impinges on a baffle plate which causes a first stage of oil removal with oil draining into an annular chamber. Gas then flows up through an annular passage into a filter element which causes a second stage of oil removal, combined with some centrifugal separation to cause oil to drain into a second oil drainage chamber. Filtered gas is then moveable upwardly and out through the axial outlet. This apparatus suffers from the drawback that it is of relatively complex design requiring two areas to store drained oil.

[0009] 0006 Preferred embodiments of the present disclosure seek to overcome the above disadvantages of the prior art.

[0010] SUMMARY

[0011] 0007 According to the present disclosure, there is provided a separator for separating a first fluid from a gas, the separator comprising:

[0012] 0008 an inlet for receiving a flow of gas containing a first fluid to be separated;

[0013] 0009 a separation apparatus for removing said first fluid from said flow of gas;

[0014] 0010 a separated fluid bowl for receiving said first fluid removed from said flow of gas; and

[0015] 0011 an outlet for expelling said flow of gas; 0012 wherein said inlet is arranged to direct said flow of gas against a base of said separated fluid bowl, and wherein said base of said separated fluid bowl is configured to separate said flow of gas into a peripheral gas flow around a periphery of said separated fluid bowl to flow into said separation apparatus.

[0016] 0013 By providing an inlet arranged to direct a flow of gas against a base of the separated fluid bowl, wherein the base of said separated fluid bowl is configured to separate the flow of gas into a peripheral gas flow around a periphery of the separated fluid bowl, this provides the advantage of enabling the use of heated air from the compressor to ensure that fluid stored in the separated fluid bowl does not freeze. This therefore removes the need for an additional electrical heater.

[0017] 0014 This also provides the advantage of directing gas flow into a peripheral annular flow which facilitates separation of fluid in the separation apparatus as well as facilitating use of co-axial inlets and outlets to reduce the size of the separator.

[0018] 0015 Moreover, it has been found that this configuration results in fluid separation efficiencies and pressure drops that are within acceptable limits for use in commercial separation applications.

[0019] 0016 In a preferred embodiment, wherein said inlet and outlet are disposed on a longitudinal axis of said separator.

[0020] 0017 It has been found that this configuration advantageously results in fluid separation efficiencies and pressure drops that are within acceptable limits for use in commercial separation applications. This also advantageously reduces the size of the separator. 0018 In a preferred embodiment, said separation apparatus is arranged adjacent said separated fluid bowl to define an annular space around the outside of said separation apparatus and separated fluid bowl to form a path for peripheral gas flow.

[0021] 0019 In a preferred embodiment, said separation apparatus is a cyclonic separator.

[0022] 0020 In a preferred embodiment, the separator further defines a chamber disposed at an end of said annular space, wherein said chamber is positioned to reverse the direction of flow of gas and direct said flow of gas onto vane stators to cause said flow of gas to follow a cyclonic path into said cyclonic separator.

[0023] 0021 This provides the advantage of assisting in fluid separation whilst resulting in minimal pressure drop.

[0024] 0022 In a preferred embodiment, said flow of gas is directed through cyclonic separator and subsequently out of said outlet.

[0025] 0023 In a preferred embodiment, said base of said separated fluid bowl is at least partially conical.

[0026] 0024 This provides the advantage of smoothly separating inlet gas into a peripheral annular flow path. The conical portion also advantageously provides an aerodynamic separation which reduces the pressure drop of the inlet gas.

[0027] 0025 In a preferred embodiment, the separator further comprises a drain for allowing said first fluid removed from said flow of gas to exit the separator. 0026 A longitudinal axis of said drain may be parallel to the longitudinal axis of the separator.

[0028] 0027 This provides the advantage of enabling the separator to be used in different configurations of apparatus requiring a separator.

[0029] 0028 A longitudinal axis of said drain may form an acute angle to the longitudinal axis of the separator.

[0030] 0029 This provides the advantage of enabling the separator to be used in different configurations of apparatus requiring a separator.

[0031] 0030 A longitudinal axis of said drain may be perpendicular to the longitudinal axis of the separator.

[0032] 0031 This provides the advantage of enabling the separator to be used in different configurations of apparatus requiring a separator.

[0033] BRIEF DESCRIPTION OF THE DRAWINGS

[0034] 0032 Preferred embodiments of the present disclosure will now be described, by way of example only, and not in any limitative sense, with reference to the accompanying drawings in which:

[0035] 0033 Figure 1 is a side view of a separator in accordance with a first embodiment of the present disclosure for separating a first fluid from a gas;

[0036] 0034 Figure 2 is a cross-sectional view taken along line A-A of the separator of Figure 1 ;

[0037] 0035 Figure 3 is perspective view of the separator of Figures 1 and 2;

[0038] 0036 Figure 4 is a cross sectional view of the separator of Figures 1 to 3 demonstrating the gas flow path through the separator; 0037 Figure 5a is a side view of a separator in accordance with a second embodiment of the present disclosure for separating a first fluid from a gas;

[0039] 0038 Figure 5b is a perspective view of the separator of Figure 5a;

[0040] 0039 Figure 5c is a cross-section taken along line A-A of Figure 5a;

[0041] 0040 Figure 6a is a side view of a separator in accordance with a third embodiment of the present disclosure for separating a first fluid from a gas;

[0042] 0041 Figure 6b is a cross-section of the separator of Figure 6a taken along line C-C; and

[0043] 0042 Figure 6c is a perspective view of the separator of Figure 6a.

[0044] DETAILED DESCRIPTION

[0045] 0043 Referring to Figures 1 to 3, a separator 2 for separating a first fluid from a gas comprises an inlet 4 for receiving a flow of gas containing a first fluid to be separated, a separation apparatus 6 for removing the first fluid from the flow of gas, a separated fluid bowl 8 for receiving the first fluid removed from the flow of gas and an outlet 10 for expelling the flow of gas.

[0046] 0044 The inlet 4 is arranged to direct the flow of gas against the base 12 of the separated fluid bowl, the base 12 of the separated fluid bowl 8 being configured to separate the flow of gas into a peripheral gas flow around a periphery 14 of the separated fluid bowl 8 to then flow into the separation apparatus 6. 0045 Separator 2 may be for example a water separator to be used in the air and hydrogen circuits of a hydrogen fuel cell system. Compressed air in such systems is heated by the compressor and is often laden with moisture which must be removed, hence the requirement for separator 2.

[0047] 0046 The inlet 4 and outlet 10 are aligned on longitudinal axis A-A of the separator 2. The separated fluid bowl 8 and separation apparatus 6 are disposed adjacent to one another to define an annular space 16 through which a peripheral annular flow of gas can flow. Chamber 18 is formed at the end of annular space 16 to commence both a swirling of gas flow and a reversal of direction of gas flow to impinge on vane stators 20. Chamber 18 is concentric with outlet tube 30 to enable gas to circulate outlet tube 30.

[0048] 0047 Gas flow crossing vane stators 20 is directed to circulate in separation apparatus 6 which is preferably a cyclone separator 22. Water separated in cyclone separator 22 and chamber 18 flows downwardly through perforated screen 24 into the fluid collection bowl 8 and can subsequently be released through drain 26. The longitudinal axis X of drain is parallel to the longitudinal axis A-A of the separator 2. This enables separator 2 to be mounted vertically in apparatus in which the separator 2 is to be used. Suitable mountings 28 are provided to enable the separator to be attached in an apparatus in which it is to be used.

[0049] 0048 Referring to Figure 4, the flow of gas through separator 2 will now be described. In particular, a flow of air through separator 2 to remove water from that air flow will be described.

[0050] 0049 Generally, in a system such as the air circuit in a hydrogen fuel cell apparatus, due to the action of a compressor on air, the air is heated. Such compressed air enters inlet 4 in the direction of arrow B and impinges on base 12 of separated fluid bowl 8. The base 12 of separated fluid bowl 8 has a partially diverging conical shape to smoothly separate gas flow into a peripheral annular flow in the direction of arrows C through annular space 16 defined by the outer peripheries of separated fluid bowl 8 and separation apparatus 6. The compressed air heats base 12 of separated fluid bowl 8.

[0051] 0050 Air flow then moves upwardly in the direction of arrow D and begins to circulate in chamber 18. As air circulates around the outside of outlet tube 30, a first stage of water separation occurs. Gas flow D then moves across vane stators 20 in the direction of arrow E and is directed to circulate in cyclone separator 22 in the direction of arrow F at which further water separations occurs due to centrifugal force. Air from which water has been separated is then expelled in the direction of arrow G from outlet 10, whilst separated water drains downwardly into the warmed separated fluid bowl.

[0052] 0051 The action of passing an initial gas flow from a compressor into inlet 4 passes warm air, which can be heated to something of the order of 80 to 100 degrees C by a compressor, against the base 12 of separated fluid bowl 8 to prevent freezing of water held in separated fluid bowl without the need for an electric heater.

[0053] 0052 The performance of separator 2 has been found to have greater than 95% water separation efficiently at a less than 50 mbar pressure drop at rated flow. This is within an acceptable range for use in a hydrogen fuel cell system.

[0054] 0053 A separator 102 of a second embodiment of the present disclosure will now be described with reference to Figures 5a to 5c with common reference numerals to the embodiment of Figures 1 to 4 but increased by 100.

[0055] 0054 Whilst separator 2 of Figures 1 to 4 is configured to be mounted in a vertical orientation in apparatus in which it is to be used, in some applications, other orientations of mounting of a separator are required. Separator 102 is therefore configured to be mounted horizontally in an apparatus which requires a separator. The parts and functioning of the separator are substantially identical to that of the embodiment of Figures 1 to 4 with the exception of the drain feature. Separator 102 comprises inlet 104, outlet 110 and an at least partially conical base 112 of a separated fluid bowl 108. However, in this embodiment, cyclone separator 122 drives gas substantially horizontally out of outlet 110 which leaves separated fluid in separated fluid bowl 108 to flow out through drain 126. It can be seen that the longitudinal axis Y of drain 126 is perpendicular to longitudinal axis A-A of the separator 102. This therefore maintains all of the advantages of the embodiment of Figures 1 to 4 but enables horizontal mounting of separator 102.

[0056] 0055 A separator 202 of a third embodiment of the present disclosure will now be described with reference to Figures 6a to 6c with reference numerals common to the embodiment of Figures 1 to 4 but increased by 200.

[0057] 0056 Again, to enable a separator to be mounted in various orientations in different apparatus, it has been found that the advantages of the separator of the embodiment of Figures 1 to 4 can be maintained whilst mounting the separator in an apparatus at an angle both offset from the horizontal and vertical.

[0058] 0057 To accomplish this, separator 202, which has parts substantially identical to the embodiment of Figures 1 to 4 other than the drain feature, comprises drain 226 which has a longitudinal axis Z forming an acute angle with longitudinal axis C-C of the separator 202. Separated fluid in separated fluid bowl 208 can therefore drain downwardly out of drain 226. 0058 It will be appreciated by persons skilled in the art that the above embodiment has been described by way of example only and not in any limitative sense, and that various alterations and modifications are possible without departure from the scope of protection as defined by the appended claims.

Claims

CLAIMS1 . A separator for separating a first fluid from a gas, the separator comprising: an inlet for receiving a flow of gas containing a first fluid to be separated; a separation apparatus for removing said first fluid from said flow of gas; a separated fluid bowl for receiving said first fluid removed from said flow of gas; and an outlet for expelling said flow of gas; wherein said inlet is arranged to direct said flow of gas against a base of said separated fluid bowl, and wherein said base of said separated fluid bowl is configured to separate said flow of gas into a peripheral gas flow around a periphery of said separated fluid bowl to flow into said separation apparatus.

2. The separator according to claim 1 , wherein said inlet and outlet are disposed on a longitudinal axis of said separator.

3. The separator according to claim 2, wherein said separation apparatus is arranged adjacent said separated fluid bowl to define an annular space around the outside of said separation apparatus and separated fluid bowl to form a path for peripheral gas flow.

4. The separator according to claim 3, further defining a chamber disposed at an end of said annular space, wherein said chamber is positioned to reverse the direction of flow of gas and direct said flow of gas onto vane stators to cause said flow of gas to follow a cyclonic path into said cyclonic separator.

5. The separator according to any preceding claim, wherein said separation apparatus is a cyclonic separator.

6. The separator according to claim 5, further defining a chamber disposed at an end of said annular space, wherein said chamber is positioned to reverse the direction of flow of gas and direct said flow of gas onto vane stators to cause said flow of gas to follow a cyclonic path into said cyclonic separator.

7. The separator according to claim 6, wherein said flow of gas is directed through cyclonic separator and subsequently out of said outlet.

8. The separator according to any preceding claim, wherein said base of said separated fluid bowl is at least partially conical.

9. The separator according to any preceding claim, further comprising a drain for allowing said first fluid removed from said flow of gas to exit the separator.

10. The separator according to claim 9, wherein a longitudinal axis of said drain is parallel to the longitudinal axis of the separator.11 . The separator according to claim 9, wherein a longitudinal axis of said drain forms an acute angle to the longitudinal axis of the separator.

12. The separator according to claim 9, wherein a longitudinal axis of said drain is perpendicular to the longitudinal axis of the separator.

13. The separator according to any preceding claim, wherein said separation apparatus is arranged adjacent said separated fluid bowl to define an annular space around the outside of said separation apparatus and separated fluid bowl to form a path for peripheral gas flow.

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