Coalescing filter element with drainage mechanism

1. A lubricant coalescing element for use in a gas compression system, the lubricant coalescing element comprising:

a cylindrical outer screen member;

at least one filter element disposed inside the cylindrical outer screen member and being coaxial with the cylindrical outer screen member; and

a drainage arrangement in contact with the at least one filter element to drain accumulated lubricant out of the at least one filter element, the drainage arrangement comprises a drainage member disposed between the cylindrical outer screen member and the at least one filter element and the drainage member has an arched shape with a curved part of the arched shape disposed in contact with the at least one filter element.

2. The lubricant coalescing element of claim 1 wherein the drainage member is located at a bottom most part of the at least one filter element.

3. A lubricant coalescing element for use in a gas compression system, the lubricant coalescing element comprising:

a cylindrical outer screen member;

at least one filter element disposed inside the cylindrical outer screen member and being coaxial with the cylindrical outer screen member; and

a drainage arrangement in contact with the at least one filter element to drain accumulated lubricant out of the at least one filter element, the drainage arrangement comprises a drainage member disposed between the cylindrical outer screen member and the at least one filter element and the drainage member is a strip with rounded edges and a rounded edge of the strip is disposed in contact with the at least one filter element.

4. The lubricant coalescing element of claim 1 wherein the drainage member extends substantially uninterrupted along the at least one filter element.

5. The lubricant coalescing element of claim 1 wherein the at least one filter element comprises a plurality of filter elements, the plurality of filter elements are arranged concentrically and are coaxial with the cylindrical outer screen member.

6. The lubricant coalescing element of claim 5 wherein the drainage arrangement comprises at least one additional drainage member.

7. The lubricant coalescing element of claim 6 wherein the at least one additional drainage member is disposed between adjacent filter elements of the plurality of filter elements.

8. The lubricant coalescing element of claim 1 wherein the drainage member comprises a plurality of drainage members disposed between the cylindrical outer screen member and the at least one filter element.

9. The lubricant coalescing element of claim 8 wherein the plurality of drainage members comprises two drainage members, the two drainage members being disposed opposite one another at a bottom most part of the at least one filter element and a top most part of the at least one filter element.

10. The lubricant coalescing element of claim 1 wherein the drainage member is integral with the cylindrical outer screen member.

11. The lubricant coalescing element of claim 10 wherein:

the at least one filter element comprises a plurality of filter elements, the plurality of filter elements are arranged concentrically and are coaxial with the cylindrical outer screen member; and

the drainage arrangement further comprises at least one additional drainage member disposed between adjacent filter elements of the plurality of filter elements.

12. A lubricant coalescing element for use in a refrigeration system, the lubricant coalescing element comprising:

a cylindrical outer screen member;

at least one filter element disposed inside the cylindrical outer screen member and being coaxial with the cylindrical outer screen member; and

at least one drainage member in contact with the at least one filter element and disposed between the cylindrical outer screen member and the at least one filter element to drain accumulated lubricant out of the at least one filter element, the at least one drainage member has an arched shape with a curved part of the arched shape disposed in contact with the at least one filter element.

13. A lubricant coalescing element for use in a refrigeration system, the lubricant coalescing element comprising:

a cylindrical outer screen member;

at least one filter element disposed inside the cylindrical outer screen member and being coaxial with the cylindrical outer screen member; and

at least one drainage member in contact with the at least one filter element and disposed between the cylindrical outer screen member and the at least one filter element to drain accumulated lubricant out of the at least one filter element, the at least one drainage member is a strip with rounded edges and a rounded edge of the strip is disposed in contact with the at least one filter element.

14. The lubricant coalescing element of claim 12 wherein the at least one drainage member extends substantially uninterrupted along the at least one filter element.

15. The lubricant coalescing element of claim 12 wherein the at least one filter element comprises a plurality of filter elements, the plurality of filter elements are arranged concentrically and are coaxial with the drainage arrangement.

16. The lubricant coalescing element of claim 15 further comprising at least one second drainage member disposed between adjacent filter elements of the plurality of filter elements.

17. The lubricant coalescing element of claim 12 wherein the at least one drainage member is integral with the cylindrical outer screen member.

18. The lubricant coalescing element of claim 17 further comprising:

at least one second drainage member;

the at least one filter element comprises a plurality of filter elements, the plurality of filter elements are arranged concentrically and are coaxial with the cylindrical outer screen member; and

wherein the at least one second drainage member is disposed between adjacent filter elements of the plurality of filter elements.

19. A separator arrangement to remove entrained lubricant from a compressed gas, the separator arrangement comprising:

a shell having an inlet port and a discharge port;

a first stage disposed in the shell, the first stage being configured to change a direction of flow of gas entering the shell through the inlet port;

a second stage disposed in the shell adjacent to the first stage, the second stage being configured to remove lubricant droplets from the gas flow; and

a third stage disposed in the shell adjacent to the second stage, the third stage being configured to remove entrained lubricant mist and aerosol from the gas flow, the third stage comprising a coalescing element, the coalescing element comprising:

a cylindrical outer screen member disposed horizontally in the third stage;

at least one filter element disposed inside the cylindrical outer screen member and being coaxial with the outer screen member; and

a drainage arrangement in contact with the at least one filter element to drain accumulated lubricant out of the at least one filter element, wherein the drainage arrangement comprises at least one drainage member disposed between the cylindrical outer screen member and the at least one filter element and the at least one drainage member has an arched shape with a curved part of the arched shape disposed in contact with the at least one filter element.

20. The separator arrangement of claim 19 wherein the second stage comprises a mesh pad.

21. The separator arrangement of claim 19 wherein the discharge port is disposed adjacent to the third stage and the third stage comprises a lubricant sump.

22. The separator arrangement of claim 19 wherein the coalescing element has an open end to receive the gas flow from the second stage and a closed end disposed opposite the open end to force the gas flow through the at least one filter element.

23. The separator arrangement of claim 19 wherein the at least one drainage member extends substantially uninterrupted along the at least one filter element.

24. The separator arrangement of claim 19 wherein the at least one filter element comprises a plurality of filter elements, the plurality of filter elements are arranged concentrically and are coaxial with the cylindrical outer screen member.

25. The lubricant coalescing element of claim 24 wherein the drainage arrangement further comprises at least one second drainage member, the at least one second drainage member is disposed between adjacent filter elements of the plurality of filter elements.

26. The separator arrangement of claim 19 wherein the drainage arrangement is integral with the cylindrical outer screen member.