Bag for Pressure Leaf Filter

Patent metadata

Field	Value
Publication number	US-2021362084-A1
Application number	US-202117323071-A
Country	US
Kind code	A1
Filing date	May 18, 2021
Priority date	May 19, 2020
Publication date	Nov 25, 2021
Grant date	—

Abstract

A leaf filter bag for a leaf (110) of a pressure leaf filter (100) has a first sheet portion (50), adjacent to a second sheet portion (60). The first sheet portion (50) is connected to the second sheet portion (60) at a first edge (10), a second edge (20) and a third edge (30). Forth edges of the sheet portions define an openable and closable edge (40) which has an open position and a closed position, which allows inserting a frame (122) of the leaf (110) into the leaf filter bag (1) through an opening formed by the openable and closable edge (40) in the open position. A zipper (42) closure (41) is provided at the openable and closable edge (40), and a further hook-and-loop fastener closure may be provided.

First claim

I claim:

1 . A leaf filter bag for a leaf of a pressure leaf filter, the leaf filter bag comprising:
a first sheet portion; a second sheet portion adjacent to the first sheet portion, and connected to the first sheet portion along a first edge, a second edge and a third edge to define an enclosure for a leaf, wherein an openable and closable edge is defined by the first sheet portion and the second portion between the first edge and the second edge which defines an opening for the reception into the enclosure of a frame of the leaf in an open position; and a closure comprising a zipper and a hook-and-loop fastener, wherein the zipper is positioned at the openable and closable edge for closing the openable and closable edge after the frame of the leaf is received within the enclosure defining a closed position of the leaf filter bag, wherein the zipper is placed along the length of the openable and closable edge of the leaf filter bag, and wherein the hook-and-loop fastener is fixed to the filter bag along the length of the openable and closable edge.

2 . The leaf filter bag of claim 1 wherein the zipper in the closed position closes the filter bag so that the hook-and-loop fastener, or at least a part of the hook-and-loop fastener, is inside the filter bag.

3 . The leaf filter bag of claim 1 wherein the hook-and-loop fastener covers the zipper or at least part of the zipper in the closed position.

4 . The leaf filter bag of claim 1 wherein the closure further comprises one or more than one hook-and-loop strip(s).

5 . The leaf filter bag of claim 1 wherein the openable and closable edge comprises an outlet pipe aperture for reception therethrough of an outlet pipe of the leaf and the closure is placed along the length of the openable and closable edge from the first edge to the outlet pipe aperture.

6 . The leaf filter bag of claim 5 , wherein the zipper is placed along the length of the openable and closable edge from the first edge of the leaf filter bag to the outlet pipe aperture of the leaf filter bag.

7 . The leaf filter bag of claim 1 , wherein the closure is placed along the entire length of the openable and closable edge from the first edge to the second edge.

8 . The leaf filter bag of claim 1 , wherein the leaf filter bag is a single pocket filter bag.

9 . The leaf filter bag of claim 1 further comprising a horizontal pressure leaf filter, wherein the leaf filter bag is secured on to a leaf of the horizontal pressure leaf filter.

10 . The leaf filter bag of claim 1 further comprising a vertical pressure leaf filter, wherein the leaf filter bag is secured on to a leaf of the vertical pressure leaf filter.

11 . The leaf filter bag of claim 1 wherein the first sheet portion has an exterior surface and an opposite inner surface, and wherein the second sheet portion has an exterior surface and an opposite inner surface, wherein the first sheet portion is connected to the second sheet portion such that the first sheet portion inner surface faces the second sheet portion inner surface, and wherein the hook and loop fastener comprises a first part fastened to the outer surface of the first sheet portion and a second part fastened to the inner surface of the second sheet portion, and wherein the zipper comprises a first part fastened to the outer surface of the first sheet portion outwardly of the hook and loop fastener first part, and a second part fastened to the inner surface of the second sheet portion outwardly of the hook and loop fastener second part, and further comprising:
a first flap fastened to the outer surface of the first sheet, wherein the first part of the zipper is fastened to the first flap; and
a second flap fastened to the inner surface of the second sheet portion, wherein the second part of the hook and loop fastener is positioned on the second flap such that the second flap is passable over the enclosed leaf to engage the first part of the hook and loop fastener, and wherein the first part of the zipper is fastened to the first flap and such that the second sheet portion with the second part of the zipper thereon is passable over the engaged parts of the hook and loop fastener to engage the first flap first zipper part.

12 . The leaf filter bag of claim further 1 comprising a pipe flap which extends outwardly from the first sheet portion and the second sheet portion, and wherein the zipper has two parts, one secured to each of the first sheet portion and the second sheet portion beneath the outlet pipe 113 and which extend upwardly and outwardly onto the pipe flap, such that when the zipper is zipped closed the pipe flap is formed into an encircling tube which can extend around an outlet pipe of a leaf enclosed within the leaf filter bag.

13 . The leaf filter bag of claim 12 further comprising a hook and loop fastener strip secured to the pipe flap for wrapping around the pipe flap to encircle and secure the zipped pipe flap about an outlet pipe.

14 . A method for installing a leaf filter bag comprising an openable and closable edge on to a leaf of a pressure leaf filter, comprising:
inserting the leaf through the openable and closable edge into an interior volume of the leaf filter bag which is selectively sealed between an open and a closed position, the leaf filter bag having a closure comprised of a zipper and a hook-and-loop fastener extending along an openable and closable edge; and securing the filter bag onto the leaf of the pressure leaf filter by sealing said closure.

15 . The method of claim 14 , wherein the filter bag further comprises one or more than one hook-and-loop strip(s), the method further comprising the steps of:
attaching the filter bag onto the leaf by using the one or more than one hook-and-loop strip(s), and/or sealing an outlet pipe aperture of the filter bag onto an outlet pipe of the leaf by using the one or more than one hook-and-loop strip(s).

16 . The method of claim 15 further comprising the step of using the leaf filter bag in alumina production.

17 . A leaf filter bag for a leaf of a pressure leaf filter, the leaf filter bag comprising:
a first sheet having an exterior surface and an opposite inner surface; a second sheet having an exterior surface and an opposite inner surface, wherein the first sheet is connected to the second sheet such that the first sheet inner surface faces the second sheet inner surface, the first and second sheets having edges which are fixed to one another to define an enclosure between the sheets for a leaf, and the first sheet and the second sheet each having an outward edge, the enclosure having an opening for the reception into the enclosure of a frame of the leaf; a hook and loop fastener comprising a first part fastened to the outer surface of the first sheet and a second part fastened to the inner surface of the second sheet; a zipper comprising a first part fastened to the outer surface of the first sheet outwardly of the hook and loop fastener first part, and a second part fastened to the inner surface of the second sheet outwardly of the hook and loop fastener second part; wherein the second sheet is positionable to bring the hook and loop fastener second part into engagement with the hook and loop fastener first part, and the zipper second part into zipping engagement with the zipper first part, to thereby secure the bag about the leaf received within the enclosure.

18 . The leaf filter bag of claim 17 further comprising a first flap fastened to the outer surface of the first sheet, wherein the first part of the

Assignees

• Valmet Technologies Oy

Inventors

• Manoel Marilene Amaral Leite
• Zica Rafael De Felipe
• Fonseca Siterzany
• Bacelar Wallace Farias
• Pavan Thiago

Classifications

• B01D29/27 Primary

  Filter bags · CPC title

• C01F7/02

  Aluminium oxide; Aluminium hydroxide; Aluminates · CPC title

• B01D29/96

  in which the filtering elements are moved between filtering operations; Particular measures for removing or replacing the filtering elements; Transport systems for filters (B01D29/09, B01D29/70 take precedence) · CPC title

• B01D29/111

  Making filtering elements · CPC title

• B01D29/39 Primary

  with hollow discs side by side on, or around, one or more tubes, e.g. of the leaf type · CPC title