Liquid filter unit with laterally arranged filters and method of operation thereof

Abstract

The filter unit includes a housing, a first filter and a second filter disposed within the housing, and a liquid flow path extending sequentially through the first filter and the second filter. The first filter includes a first axial end secured to the housing and a first filter medium. The second filter includes a first axial end secured to the housing and a second filter medium. Liquid is guided radially outward through the first filter medium and radially inward through the second filter medium. A method of filtering liquid in the filter unit includes passing liquid radially outward through the first filter medium of the first filter, directing liquid from the first filter to the second filter, and passing liquid radially inward through a second filter element of the second filter.

Description

[Technical field]

[0001] The present disclosure relates generally to a filter unit and, more particularly, to a filter unit configured to filter a liquid. [Background technology]

[0002] Filters can be used in semiconductor manufacturing to remove contaminants from a fluid. A fluid (e.g., liquid, water, etc.) is directed through a filter unit. The filter unit can be configured to remove contaminants from the liquid as the liquid passes through the filter. The contaminants can include, for example, solid particles, liquid impurities, and dissolved chemical species. Summary of the Invention

[0003] In one embodiment, a filter unit for filtering liquid includes a housing having an inlet and an outlet, a first filter disposed within the housing, a second filter disposed within the housing, and a liquid flow path. The first filter includes a first axial end secured to an inner surface of the housing, an axial inlet disposed above an opening of the inlet of the housing, and a first filter medium. The second filter includes a first axial end secured to an inner surface of the housing, an axial outlet disposed above an opening of the outlet of the housing, and a second filter medium. The liquid flow path extends from the inlet to the outlet sequentially through the first filter medium and the second filter medium. Liquid in the liquid flow path flows radially outward through the first filter medium and radially inward through the second filter medium.

[0004] In one embodiment, a method is directed to filtering a liquid in a filter unit. The filter unit includes a housing having an inlet and an outlet. The method includes directing the liquid from the inlet of the housing to a filter media of a first filter disposed within the housing. The first filter includes a first axial end secured to an inner surface of the housing and an axial inlet disposed above an opening of the inlet of the housing. The method also includes passing the liquid radially outward through the first filter media and directing the liquid from the first filter media to a second filter media of a second filter disposed within the housing. The second filter includes a first axial end secured to an inner surface of the housing and an axial outlet disposed above an opening of the outlet of the housing. The method also includes passing the liquid radially inward through the second filter media. [Brief description of the drawings]

[0005] [Figure 1] FIG. 2 is a side perspective view of one embodiment of a filter unit. [Diagram 2] 2 is a cross-sectional view of the filter unit of FIG. 1 according to one embodiment. [Diagram 3] 3 is a perspective view of a cross section of the filter unit of FIG. 2 according to one embodiment. [Figure 4] FIG. 2 is a block flow diagram of one embodiment of a method for filtering a liquid in a filter unit. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0006] Like numbers refer to like features.

[0007] FIG. 1 shows a side perspective view of one embodiment of a filter unit 1. The filter unit 1 is configured to filter a fluid. The fluid is filtered as it passes through the filter unit 1. Flow into and out of the filter unit 1 is indicated by dashed arrows in FIG. 1. The filter unit 1 includes a housing 10 that houses filters 40, 60, which may be arranged laterally relative to one another (shown in FIG. 2). The filter unit 1 is a removable filter unit 1 configured to be removed and replaced after removing a certain amount of containment. In one embodiment, the filter unit 1 can be configured to be installed in a filter manifold (not shown). For example, the filter manifold can include an inlet tube / pipe (not shown) and an outlet tube / pipe (not shown) that are connected to the filter unit 1 and feed the fluid through the filter unit 1.

[0008] As shown in FIG. 1, the housing 10 includes an inlet 12 and an outlet 14. A liquid (to be filtered) enters the filter unit 10 through the inlet 12. The liquid is filtered within the housing 10, and the filtered liquid is then discharged from the filter unit 1 through the outlet 14. The filter unit 1 is configured to filter liquids used in semiconductor manufacturing. For example, in some embodiments, the filter unit 1 is configured to filter and wash liquids used in photolithography and / or wet etching. The liquid filtered by the filter unit 1 may include one or more acids, bases, oxidizing agents, and / or reducing agents, or any combination thereof. For example, the liquid may be water (e.g., deionized water), HCl, HNO3, isopropyl alcohol, etc. The housing 10 may also include a vent 16 to allow the evacuation of gas from the filter unit 1. For example, the vent 16 is configured to allow gas (e.g., air bubbles, etc.) entering with the liquid to be released from the housing 10.

[0009] In the illustrated embodiment, the housing 10 includes a base 20 and a cover 22 attached to the base 20. The housing 10 may be assembled mechanically and / or via bonding (e.g., thermal bonding, adhesive bonding, etc.). As shown in the illustrated embodiment, the housing 10 may be assembled via bonding (e.g., cover 22 thermally bonded to base 20). For example, the cover 20 may be bonded (e.g., thermal bonding, adhesive bonding, etc.) to the base 20. In one embodiment, the housing 10 may be mechanically assembled (e.g., cover 22 mechanically attached to base 20). For example, the cover 22 and the base 20 may be configured and mechanically secured to one another via a snap fit, via a lock-and-key mechanism, etc. In such an embodiment, the housing 10 may include a seal (not shown) to provide a seal between the cover 22 and the base 20. As shown in FIG. 1, the inlet 12 and the outlet 14 may be formed in the cover 22. The inlet 12 and the outlet 14 are provided on the same side of the housing 10 (e.g., the top side 23 of the housing 10). In one embodiment, the housing 10 may also include a drain (not shown) that allows liquid to be drained from the housing 10 before the filter unit 1 is removed. For example, the drain may be provided at the base 20 of the housing 10 (e.g., the bottom surface of the housing 10). It should be appreciated that the housing 10 in one embodiment may have the inlet 12 and outlet 14 formed on different sides of the housing 10. In other embodiments, the housing 10 may be formed to have a different shape and / or different portions than the base 20 and cover 22 shown in FIG. 1.

[0010] FIG. 2 is a cross-sectional view of the filter unit 1. For example, the cross-section of the view of FIG. 2 is taken along line II-II of FIG. 1. As shown in FIG. 2, the filter unit 1 includes a housing 10, a first filter 40, and a second filter 60. The housing 10 has an enclosed internal volume 24. The filters 40, 60 are disposed within the housing 10. As shown in FIG. 2, the filters 40, 60 are disposed within the internal volume 24 of the housing 10. The filter unit 1 has a liquid flow path F through which liquid flows through the filter unit 1. The liquid flow path F extends from the inlet 12 to the outlet 14, passing through the first filter 40 and the second filter medium 60 in sequence. As the liquid passes through the liquid flow path F, it is filtered by the filters 40, 60.

[0011] The first filter 40 includes a first filter media 42, a first axial end 44, a second axial end 46, and an axial inlet 48. The first axial end 44 and the second axial end 46 are opposite ends of the first filter 40 along an axis A1 of the first filter 40. For example, the axis A1 is an axis that extends along the height of the tubular shape of the first filter 40. The axial inlet 48 is formed in the first axial end 44 of the first filter 40. The first filter media 42 extends along the axial direction (e.g., axial direction D1, axial direction D4) of the filter 40 between the first axial end 44 and the second axial end 46 of the first filter 40. The first filter media 42 can have a tubular shape within the first filter 40. The first filter media 42 forms a radial outlet of the first filter 40. For example, liquid enters the first filter 40 through its axial inlet 48 and exits the first filter 40 (after being filtered) from its first filter media 42 .

[0012] The first axial end 44 of the first filter 40 is secured to the inner surface 26 of the housing 10. The first axial end 44 of the first filter 40 can be bonded or mechanically secured to the inner surface 26 of the housing 10. In the illustrated embodiment, the first axial end 44 is bonded (e.g., thermally bonded, adhesively bonded, etc.) to the housing 10. In one embodiment, the first axial end 44 may be mechanically secured to the housing 10 via a snap fit, threads (e.g., the first axial end 44 has threads that screw into the inner surface 26 of the housing 10), etc. The first axial end 44 of the first filter 40 is disposed above the opening 13 in the housing 10 for the inlet 12. Liquid flows into the first filter 40 from the opening 13 of the inlet 12. The first axial end 44 of the first filter 40 completely covers the opening 13 for the inlet 12 such that liquid flowing into the housing 10 from the inlet 12 is forced to flow into the first filter 20. The liquid then flows through the filter media 42 and is discharged from the first filter 40 into the interior volume 24 of the housing 10. The liquid enters the first filter 40 through the axial inlet 48 in an axial direction D1 and is discharged from the first filter 40 in a radial direction (e.g., in a direction D2 from axis A1, in a direction D3 from axis A1, into the plane of FIG. 2, out of the plane of FIG. 2, etc.). Within the interior volume 24 of the housing 10, the liquid then flows from the filter media 42 of the first filter 40 to the filter media 62 of the second filter 40. As shown in FIG. 2, the second axial end 46 of the first filter 40 may be configured to be spaced away from the housing 10 (e.g., from a bottom side of the housing 10).

[0013] The second filter 60 includes a filter media 62, a first axial end 64, a second axial end 66, and an axial outlet 68. The first axial end 64 and the second axial end 66 are opposite ends of the second filter 60 along an axis A2 of the second filter 60. For example, the axis A2 is an axis that extends along the length of the tubular shape of the second filter 60. The axial outlet 68 is formed in the first axial end 64 of the second filter 60. The second filter media 62 extends along the axial direction of the filter 60 (e.g., axial direction D1, axial direction D4) between the first axial end 64 and the second axial end 66 of the second filter 60. The second filter media 62 can have a tubular shape within the first filter 60. The second filter media 62 forms a radial inlet of the second filter 60. For example, liquid may enter the second filter 60 radially through its second filter media 62 and exit the second filter 60 (after being filtered) through its axial outlet 68 .

[0014] The first axial end 64 of the second filter 60 is secured to the inner surface 26 of the housing 10. The first axial end 44 of the second filter 60 can be bonded or mechanically secured to the inner surface 26 of the housing 10. In the illustrated embodiment, the first axial end 64 is bonded (e.g., thermally bonded, adhesively bonded, etc.) to the housing 10. In one embodiment, the first axial end 64 may be mechanically secured to the housing 10 via a snap fit, threads (e.g., the first axial end 64 is threaded into threads in the inner surface 26), etc. The first axial end 64 of the second filter 60 is disposed over the opening 15 in the housing 10 for the outlet 16. The first axial end 64 of the second filter 60 completely covers the opening 16 in the housing 10 for the outlet 16. The first axial end 64 forms a sealed connection with the inner surface 26 of the housing 10 such that fluid in the open interior volume 24 is forced to flow through the second filter 60 and exit the housing 10 and filter unit 1 .

[0015] As shown in Fig. 2, the first axial end 44 of the first filter 40 and the first axial end 64 of the second filter 60 can be fixed to the same side of the housing 10. For example, the first axial ends 44, 64 of the filters 40, 60 are each coupled to the top side (e.g., cover 22) of the housing 10 in Fig. 2. In one embodiment, the openings 13, 15 in the inner surface 26 of the housing 10 for the inlet 12 and the outlet 14 may be located on different sides (e.g., top, bottom, sidewall, etc.) of the housing 10. In such an embodiment, the first axial ends 44, 64 of the filters 40, 60 may be coupled to said different sides of the housing 10.

[0016] The first axial end 64 of the second filter 60 is disposed above the opening 15 in the housing 10 for the inlet 14. Liquid entering the second filter 60 is discharged from the second filter 60 through its axial outlet 68 to the outlet 14 in the housing 10. The liquid flows from the axial outlet 68 of the second filter 60 to the outlet 14 of the housing 10. The liquid then flows out of the filter unit 1 through the outlet 14 of the housing 10. The filter media 62 forms a radial inlet of the second filter 60. The liquid (which flows through the internal volume 24 and is discharged from the first filter 40) enters the second filter 60 radially (e.g., in a direction D2 toward the axis A2, in a direction D3 toward the axis A2, in a direction in the plane of the paper in FIG. 2, out of the plane of the paper in FIG. 2, etc.) through the filter media 62 and is discharged from the second filter 60 axially (e.g., in a direction D4). As shown in FIG. 2, the second axial end 66 of the second filter 60 may be configured to be spaced away from the housing 10 (eg, from a bottom side of the housing 10).

[0017] A liquid flow path F extends through the housing 10 from the inlet 12 to the outlet 14. The liquid flow path is configured to extend sequentially through the filters 40, 60. The liquid flow path F extends sequentially through the first filter medium 42 of the first filter 40 and the second filter 60 from the inlet 12 to the outlet 14. The liquid is first filtered by the first filter medium 42 and then by the second filter medium 62 (e.g., the liquid filtered by the first filter medium 42 is further filtered by the second filter medium 62). The liquid flow path F is formed from a plurality of portions f1, f2, f3, f4, f5. In one embodiment, the portions f1, f2, f3, f4, f5 of the flow path are connected in series with each other. For example, the second portion f2 connects the first portion f1 to the third portion f3 (e.g., the second portion f2 extends from the end of the first portion f1 to the beginning of the third portion f3).

[0018] A first portion f1 of the liquid flow path F extends through the first filter 40 along the axis A1 of the first filter 40. For example, the first portion f1 extends from the inlet 12 of the housing 10 through the axial inlet 48 into the first filter 40. The first portion f1 of the liquid flow path F guides the liquid (to be filtered) from the inlet 12 of the housing 10 to the first filter 40. A second portion f2 of the liquid flow path F extends radially outward through the first filter media 42. For example, the second portion f2 extends from the first filter 24 through the first filter media 42 into the interior volume 24 of the housing 10. The second portion f2 is configured to guide the liquid to flow radially outward from the first filter media 42 of the first filter 40 (e.g., in a direction D2 from the axis A1, a direction D3 from the axis A1, a direction into the page from the axis A1, a direction out of the page from the axis A1, etc.). The liquid is filtered as it passes through the first filter media 42. For example, in the illustrated embodiment, the liquid is filtered as it passes through the resin beads of the first filter media 42. The liquid filtered by the first filter media 42 is then discharged axially from the first filter into the interior volume 24 of the housing 10.

[0019] The third portion f3 of the liquid flow path F extends from the first filter media 42 of the first filter 40 to the second filter media 62 of the second filter 60. As shown in FIG. 3, the third portion f3 extends from the first filter 40 to the second filter 60 through the open portion interior volume 24 of the housing 10. For example, as shown in FIG. 2, the third portion f3 can extend through the exterior interior volume 24 of both the first filter 40 and the second filter 60. As shown in FIG. 2, the third portion f3 can extend in the same direction as the second portion f2 (e.g., direction D2).

[0020] A fourth portion f4 of the liquid flow path F extends radially inward through the second filter media 62. The fourth portion f4 extends from the outside of the second filter 60 (e.g., from the interior volume 24) into the second filter 60. The fourth portion f4 extends radially inward (e.g., in a direction D2 toward the axis A2, a direction D2 toward the axis A2, a direction from the axis A2 into the page, a direction from the axis A2 out of the page, etc.) into the second filter 60. As shown in FIG. 2, the second portion f2, the third portion f3, and the fourth portion f4 may all extend in the same direction D2.

[0021] The fifth portion f5 of the liquid flow path F extends through the second filter 60 along the axis A2 of the second filter 60. For example, the fifth portion f5 extends from within the second filter 60 through the axial outlet 68 to the outlet 14 of the housing 10. The fifth portion f5 of the liquid flow path F guides the filtered liquid from the second filter 60 to the outlet 14 of the housing 10. The fifth portion f5 extends axially (e.g., in the direction D4) through the second filter 60. For example, the fifth portion f5 can extend in the axial direction D4 opposite to the first portion f1. The fifth portion f5 is configured to guide the liquid (after being filtered by the second filter medium 42) from the second filter 60 to the outlet 14 of the housing. The filtered liquid is then discharged from the filter unit 1 through the outlet 14 of the housing 10. Liquid (to be filtered) enters the filter unit 1 through the inlet 12 and passes in turn through the filters 40 , 42 and their filter media 42 , 62 , and then the filtered liquid is discharged through the outlet 14 .

[0022] The filters 40, 60 of the filter unit 1 may be configured to filter contaminants including, for example, solid particulates, liquid impurities (e.g., organics, etc.), and / or dissolved species (e.g., dissolved metals, ions, etc.). The filter media 42, 62 used in the filter unit 1 may be selected such that the filter unit 1 removes the desired contaminants from the liquid.

[0023] As shown in FIG. 2, the first filter media 42 and the second filter media 62 are different types of filter media. In such an embodiment, the first filter media 42 provides a first type of contaminant filtration and the second filter media 62 provides a second type of contaminant filtration. For example, the first filter media 42 can provide metal ion filtration and the second filter media 62 can provide particulate filtration. In one embodiment, the first filter media 42 may generate particles (e.g., resin beads, etc.) during use and the second filter media 62 can provide particulate filtration that captures the particles generated by the first filter media 42. This can advantageously allow a single filter unit to provide multiple types of contaminant filtration within a single unit and / or use filter media of types that generate particles.

[0024] In one embodiment, the first filter media 42 and the second filter media 62 can be the same type of filter media. In such an embodiment, the first filter media 42 and the second filter media 62 provide the same type of contaminant filtration. The first filter media 42 can be configured to remove contaminants up to a first concentration in the liquid, and the second filter media 62 can be configured to further remove contaminants up to a second, lower concentration in the liquid. This can advantageously allow the filter unit to provide high-load filtration for liquids containing large amounts of contaminants.

[0025] In the illustrated embodiment, the first filter media 42 is resin beads. The resin beads are in the form of a packed bed. In one embodiment, the resin beads can be of one type (single component) or multiple types (multi-component). In the illustrated embodiment, the second filter media 62 is a thin film. The thin film filter in one embodiment can have a single layer or multiple layers (e.g., fabric layers, polymer coating layers, etc.). In one embodiment, the first filter media 42 and the second filter media 62 may each be selected from one of a thin film, resin beads, hollow fibers, deep fibers, sponge-based media, or combinations thereof. For example, the thin film can be configured to filter organics, metals, particles, ions (e.g., cations and anions), etc. from the liquid. For example, the resin beads can be configured to filter metal-organics (e.g., resin beads in the form of an activated carbon bed, etc.). For example, the deep fibers are generally configured for use in high pollutant loading applications.

[0026] FIG. 3 is a perspective cross-sectional view of the filter unit 1. FIG. 3 is a perspective view of the cross-section of FIG. 2. The filters 40, 60 are each hollow. The filters 40, 60 each have a tubular shape. The tubular shapes are capped at the second axial ends 46, 66. As shown in FIG. 3, the tubular shape of each filter 40, 60 is cylindrical. It should be appreciated that the filters 40, 60 may have different tubular shapes in other embodiments. For example, one or both of the filters 40, 60 may have a square tubular shape, an elliptical tubular shape, a triangular tubular shape, a non-polygonal tubular shape, etc. in other embodiments. In such embodiments, the filters 40, 60 may have the same or different shapes. Liquid is discharged radially from the first filter media 42 of the first filter 40. For example, liquid may be discharged radially from the first filter 40 in the directions D2, D3, D5, D6.

[0027] As shown in Figures 2 and 3, the filters 40, 60 are spaced apart from one another within the interior volume 24 of the housing 10. The first filter 40 includes one or more side surfaces 50, 52 extending between its axial ends 44, 46. The second filter includes one or more side surfaces 70, 72 extending between its axial ends 44, 46. As shown in Figures 2 and 3, the filters 40, 60 may be disposed side by side within the housing 10. In one embodiment, the side surfaces of each filter 40, 60 may be formed by a single circumferential surface of the filter 40, 60, as shown in Figure 3. The side surfaces 50, 52, 70, 72 of the filters 40, 46 are each spaced apart from the housing 10 within the housing 10. Each of the filters 40, 46 may be configured to contact the housing 10 only via their axial ends 44, 46, 64, 66. As shown in Figures 2 and 3, each of the filters 40, 60 can be configured to have only its first axial end 44 in contact with the housing 10. For example, the first filter 40 can have a first side 50 and a second side 52 that are opposing sides of the first filter 40, and the second filter 60 can have a first side 70 and a second side 72 that are opposing sides of the second filter 60. The second side 52 of the first filter 40 and the first side 70 of the second filter 60 face each other. The first side 50 and the second side 72 of the first filter 40 face in opposite directions toward opposing side walls of the housing 10.

[0028] 4 is a flow diagram of a method 1000 of filtering a liquid in a filter unit. The method 1000 may be applied to the filter unit 1 of FIGS. 1-3. The method 1000 begins at 1010.

[0029] At 1010, a liquid is directed from an inlet (e.g., inlet 12) of a housing (e.g., housing 10) to a first filter media of a first filter (e.g., first filter media 42 of first filter 40). In one embodiment, directing the liquid at 1010 includes passing 1012 the liquid through an axial inlet (e.g., axial inlet 48) of the first filter. Method 1000 then proceeds to 1020.

[0030] At 1020, the liquid is passed radially outward through the filter media. For example, the liquid is directed from the second filter to an open space in the interior volume of the housing between the housing and the filter (e.g., the open space of interior volume 24). The method then proceeds to 1030.

[0031] At 1030, the liquid is directed from the first filter media to the second filter media of the second filter (e.g., the second filter media 62 of the second filter 60). At 1030, the liquid is directed through the open space of the interior volume of the housing between the filters. The method 1000 then proceeds to 1040.

[0032] At 1040, the liquid is passed radially inward through the second filter media. For example, the liquid is induced to enter the second filter by flowing through the second filter media. In one embodiment, method 1000 may then proceed to 1050.

[0033] At 1050, the liquid is directed from the second filter media to an outlet of the housing (e.g., outlet 14). In one embodiment, directing the liquid to an outlet of the housing at 1050 can include passing 1052 the liquid through an axial outlet of the second filter (e.g., axial outlet 68). For example, directing the liquid at 1050 can include directing the liquid from the axial outlet of the second filter to an opening in the housing for the outlet (e.g., opening 15).

[0034] It should be appreciated that the method 1000 in one embodiment may be modified to include the features discussed above with respect to the filter unit 1 of FIGS.

[0035] Aspects Any of the embodiments 1 to 10 can be combined with any of the embodiments 11 to 16.

[0036] Aspect 1. A filter unit for filtering liquids comprising: a housing having an inlet and an outlet; a first filter disposed within the housing and including a first axial end secured to an inner surface of the housing, an axial inlet disposed over an opening of the inlet in the housing, and a first filter medium; a second filter disposed within the housing and including a first axial end secured to an inner surface of the housing, an axial outlet disposed over an opening of the outlet in the housing, and a second filter medium; and a liquid flow path extending from the inlet through the first filter medium and the second filter medium, in order, to the outlet, the liquid flow path configured to direct liquid radially outward through the first filter medium and radially inward through the second filter medium.

[0037] Aspect 2. The filter unit of aspect 1, wherein the axial inlet of the first filter is formed at a first axial end of the first filter and the axial outlet of the second filter is formed at a first axial end of the second filter.

[0038] Embodiment 3. The filter unit of any one of embodiments 1 and 2, wherein the first filter media is configured to be a radial outlet of the first filter and the second filter media is configured to be a radial inlet of the second filter.

[0039] Aspect 4. The filter unit of any one of Aspects 1-3, wherein the first filter is spaced apart from the second filter within the housing.

[0040] Embodiment 5. The filter unit of any one of embodiments 1 to 4, wherein the first filter and the second filter are disposed side-by-side within the housing.

[0041] Embodiment 6. The filter unit of any one of embodiments 1-5, wherein the liquid flow path includes, in order, a first portion extending through the first filter along an axis of the first filter, a second portion extending radially outward through the first filter medium, a third portion extending from the first filter medium to the second filter medium, a fourth portion extending radially inward through the second filter medium, and a fifth portion extending through the second filter along the axis of the second filter.

[0042] Embodiment 7. The filter unit of embodiment 6, wherein the third portion extends in a first direction that is radially outer relative to the first filter and radially inner relative to the second filter.

[0043] Embodiment 8. The filter unit of any one of embodiments 1-7, wherein the first filter media and the second filter media are each selected from thin film, resin beads, hollow fibers, deep fibers, sponge-based media, or combinations thereof.

[0044] Embodiment 9. The filter unit of any one of embodiments 1-8, wherein the first filter media and the second filter media are the same type of filter media.

[0045] Embodiment 10. The filter unit of any one of embodiments 1-8, wherein the first filter media and the second filter media are different types of filter media.

[0046] Aspect 11. A method of filtering a liquid in a filter unit, the filter unit including a housing having an inlet and an outlet, the method including: directing liquid from the inlet of the housing to a filter medium of a first filter disposed within the housing, the first filter including a first axial end secured to an inner surface of the housing and an axial inlet disposed over an opening of the inlet of the housing; passing the liquid radially outwardly through the first filter medium; directing liquid from the first filter medium to a second filter medium of a second filter disposed within the housing, the second filter including a first axial end secured to an inner surface of the housing and an axial outlet disposed over an opening of the outlet of the housing; and passing the liquid radially inwardly through the second filter medium.

[0047] Embodiment 12. The method of embodiment 11, further comprising directing liquid from the second filter media to an outlet of the housing.

[0048] Embodiment 13. The method of any one of embodiments 11 and 12, wherein directing the liquid from the second filter media to the outlet of the housing comprises passing the liquid through an axial outlet of the second filter.

[0049] Embodiment 14 The method of any one of embodiments 11-13, wherein directing the liquid from the first filter media to the second filter media of the second filter comprises directing the liquid.

[0050] Embodiment 15. The method of any one of embodiments 11-14, wherein directing the liquid from the inlet of the housing to the filter media of the first filter comprises passing the liquid through an axial inlet of the first filter.

[0051] Embodiment 16 The method of any one of embodiments 11-15, wherein the first filter medium and the second filter medium are selected from one of a thin film, a resin bead, a hollow fiber, a deep fiber, a sponge-based media, or a combination thereof.

[0052] The examples disclosed in this application should be considered in all respects as illustrative and not restrictive. The scope of the present invention is indicated by the appended claims, rather than the foregoing description, and all modifications that come within the meaning and scope of the claims are intended to be embraced therein.

Claims

1. A filter unit for filtering a liquid, comprising: a housing having an inlet and an outlet; a first filter disposed within the housing, the first filter including a first axial end secured to an inner surface of the housing, an axial inlet disposed over the inlet opening of the housing, and a first filter media; a second filter disposed within the housing, the second filter including a first axial end secured to the inner surface of the housing, an axial outlet disposed over the outlet opening in the housing, and a second filter media; a liquid flow path extending from the inlet through the first filter media and the second filter media, in sequence, to the outlet, the liquid flow path being configured to direct the liquid radially outward through the first filter media and radially inward through the second filter media; The filter unit comprises:

2. the axial inlet of the first filter is formed at the first axial end of the first filter; the axial outlet of the second filter is formed at the first axial end of the second filter; The filter unit according to claim 1 .

3. the first filter media is configured to be a radial outlet of the first filter; the second filter media is configured to be a radial inlet of the second filter; The filter unit according to claim 1 .

4. The filter unit of claim 1 , wherein the first filter is spaced apart from the second filter within the housing.

5. The filter unit of claim 1 , wherein the first filter and the second filter are disposed side-by-side within the housing.

6. The liquid flow path, in order, a first portion extending through the first filter along an axis of the first filter; a second portion extending radially outward through the first filter media; and a third portion extending from the first filter media to the second filter media; and a fourth portion extending radially inward through the second filter media; and a fifth portion extending through the second filter along an axis of the second filter; The filter unit of claim 1 , comprising:

7. The filter unit of claim 6 , wherein the third portion extends in a first direction that is radially outward relative to the first filter and radially inward relative to the second filter.

8. 10. The filter unit of claim 1, wherein the first filter media and the second filter media are each selected from thin film, resin beads, hollow fibers, deep fibers, sponge-based media, or combinations thereof.

9. The filter unit of claim 1 , wherein the first filter media and the second filter media are the same type of filter media.

10. The filter unit of claim 1 , wherein the first filter media and the second filter media are different types of filter media.

11. 1. A method of filtering a liquid in a filter unit, the filter unit including a housing having an inlet and an outlet, the method comprising: directing the liquid from the inlet of the housing to a filter media of a first filter disposed within the housing, the first filter including a first axial end secured to an inner surface of the housing and an axial inlet disposed above the inlet opening of the housing; passing the liquid radially outward through the first filter media; directing the liquid from the first filter media to a second filter media of a second filter disposed within the housing, the second filter including a first axial end secured to the inner surface of the housing and an axial outlet disposed above the outlet opening of the housing; passing the liquid radially inward through the second filter media; and A method comprising:

12. directing the liquid from the second filter media to an outlet of the housing. The method of claim 11 further comprising:

13. The method of claim 12 , wherein the directing the liquid from the second filter media to an outlet of the housing comprises passing the liquid through an axial outlet of the second filter.

14. The method of claim 11 , wherein the directing the liquid from the first filter media to the second filter media of the second filter comprises directing the liquid.

15. The method of claim 11 , wherein directing the liquid from the housing inlet to the filter media of the first filter comprises passing the liquid through an axial inlet of the first filter.

16. 12. The method of claim 11, wherein the first filter media and the second filter media are selected from one of a thin film, a resin bead, a hollow fiber, a deep fiber, a sponge-based media, or a combination thereof.

Images