Rotary pressure filter apparatus with reduced pressure fluctuations

Patent metadata

Field	Value
Publication number	US-10427073-B2
Application number	US-201515322320-A
Country	US
Kind code	B2
Filing date	Jul 23, 2015
Priority date	Jul 25, 2014
Publication date	Oct 1, 2019
Grant date	Oct 1, 2019

Abstract

A rotary pressure filter apparatus, a sealing device for use with the rotary pressure filter apparatus, and a process of using the apparatus. The rotary pressure filter apparatus is designed to treat a solid-liquid mixture under pressure in successive work zones. A rotary drum moves compartments containing the solid-liquid mixture through the successive zones. The zones are separated by a sealing member, which is designed to reduce pressure fluctuations as the compartments enter a successive zone.

First claim

The invention claimed is:

1. A rotary pressure filter apparatus comprising:
a housing capable of withstanding an internal pressure above ambient;
a rotary drum having at least one round cross-section and configured to rotate inside the housing around an axis, a length of the axis defining a longitudinal direction; the rotary drum being spaced from the housing to define a annular plenum therebetween;
at least one sealing member configured to contact the rotary drum, each sealing member separating the annular plenum between the housing and the rotary drum into zones, the sealing members adapted to pressure seal each zone from the other zones, the sealing member extending in a tangential direction and in the longitudinal direction, the sealing member having at least one cutout portion such that the size of the at least one cutout portion in the tangential direction is variable along at least one portion of the longitudinal direction;
at least one material passageway adapted to allow passage of material between the annular plenum in each zone and a location outside the housing;
a plurality of compartments on an outer surface of the rotary drum and configured such that material can be flow between the plenum and the compartments, the compartments positioned so as to rotate sequentially through each of the zones as the rotary drum rotates, each compartment having at least one filter member; and
at least one filtrate outlet in fluid communication with the at least one filter member.

2. The apparatus of claim 1 , wherein said plurality of compartments comprises a plurality of rows of compartments, each row having at least two compartments.

3. The apparatus of claim 2 , wherein said at least two compartments in each row are arranged on the outer surface of the rotary drum along the longitudinal direction.

4. The apparatus of claim 1 , wherein the cutout portion has at least one taper such that the cutout portion is narrower at one portion than at another portion along the longitudinal direction.

5. The apparatus of claim 4 , wherein the at least one taper comprises a single taper extending substantially the entire longitudinal direction of the sealing member.

6. The apparatus of claim 4 , wherein at least one taper comprises multiple tapers.

7. The apparatus of claim 4 , wherein the at least one taper comprises a linear edge.

8. The apparatus of claim 1 , wherein the size of the at least one cutout portion is variable in the tangential direction along the longitudinal direction only through a partial thickness of the sealing member.

9. The apparatus of claim 1 , wherein at least one of the zones having a sealing member with a variable sized cutout portion comprises a wash zone.

10. A sealing apparatus for a rotary pressure filter, the sealing member comprising:
a sealing member having a unitary body, the unitary body having a first side extending along a length and a width of the sealing member, a second side of the sealing member being spaced from the first side and connected to the first sides by edges, the volume between the first side and the second side defining a thickness of the sealing member, the second side being curved and concave relative to the first side, the second side configured to fit flush against the surface of a cylindrical drum and including at least one cutout portion such that the width of the at least one cutout portion is variable along at least one portion of its length; and
a mechanism adapted to actuate the sealing member, the mechanism configured to move the sealing member in the direction of its thickness.

11. The apparatus of claim 10 , wherein the width of the cutout portion has at least one taper such that the cutout portion is narrower at one portion than at another portion along the longitudinal direction.

12. The apparatus of claim 11 , wherein the at least one taper comprises a single taper extending substantially the entire longitudinal direction of the sealing member.

13. The apparatus of claim 11 , wherein at least one taper comprises multiple tapers.

14. The apparatus of claim 11 , wherein the at least one taper comprises a linear edge.

15. The apparatus of claim 11 , wherein the width of the at least one cutout portion is variable along its length only through a partial thickness of the sealing member.

16. The apparatus of claim 10 , wherein the mechanism comprises a pneumatic mechanism.

17. A process for recovering a solid product from a solid/liquid mixture, comprising:
filtering a solid/liquid mixture in the rotary pressure filter apparatus of claim 1 to form the solid product as a filter cake;
removing the filter cake from the rotary pressure filter apparatus.

18. The process of claim 17 , wherein the solid/liquid mixture comprises an aromatic carboxylic acid.

19. The process of claim 17 , wherein the solid/liquid mixture comprises terephthalic acid.

20. The process of claim 19 , further comprising recovering a liquid from the solid/liquid mixture.

21. The process of claim 20 , wherein the recovered liquid comprises a solvent.

22. The process of claim 21 , wherein the solvent comprises acetic acid.

23. The process of claim 17 , wherein the solid/liquid mixture comprises purified terephthalic acid.

Assignees

• Bp Corp North American Inc
• Bp Corp North America Inc

Inventors

• Bitsch-Larsen Anders
• Keyes Timothy H
• Bartos Thomas M

Classifications

• B01D33/073 Primary

  arranged for inward flow filtration · CPC title

• B01D33/09 Primary

  with surface cells independently connected to pressure distributors · CPC title

• B01D33/801

  Driving means, shaft packing systems or the like · CPC title

• B01D33/067 Primary

  Construction of the filtering drums, e.g. mounting or sealing arrangements · CPC title

• B01D2201/347

  Radial sealings · CPC title