US 5,628,916 AGranted

Method for filtering edible oils

AssigneePall Corporation

InventorsDonald B. Stevens, Leonard R. Castellano, Thomas C. Gsell, Jeffrey M. Seibert, Barry J. Weissman

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Abstract

A method for filtering edible oils utilizing a backwashable filter assembly. A filter system having at least two filter assemblies may be utilized to remove bleaching clay and/or nickel catalyst from oil being processed for human consumption. The filter assemblies may be connected in a series and tandem manner to provide continuous and uninterrupted filtering of the edible oil. Each filter assembly preferably comprises multiple, substantially cylindrical filter elements having a porous filter medium which may be formed from polyaramid fibers. The filter elements are designed to withstand the elevated temperatures used in edible oil processing and for ease of cleaning during backwashing.

Claims25

Dependent claims

A method of filtering edible oils comprising:

(a) passing edible oil containing solid particulate matter into a backwashable filter assembly;
(b) removing the solid particulate matter from the edible oil by directing the edible oil through a fibrous filter medium having a graded pore structure, including passing the edible oil through a coarser pore upstream region and then a finer pore downstream region of at least one substantially cylindrical filter element contained within the backwashable filter assembly and accumulating the solid particulate matter directly on the at least one substantially cylindrical filter element;
(c) backwashing the at least one substantially cylindrical filter element after the cake of solid particulate matter accumulates on the at least one substantially cylindrical filter element by directing a backwash fluid through the fibrous filter medium having a graded pore structure, including passing the backwash fluid through the finer pore downstream region and then the coarser pore upstream region, to clean the at least one substantially cylindrical filter element having the solid particulate matter removed from the edible oil accumulated thereon;
and
(d) cyclically alternating between removing the solid particulate matter from the edible oil by passing the edible oil through the at least one substantially cylindrical filter element and backwashing the at least one substantially cylindrical filter element to clean the at least one substantially cylindrical filter element having solid particulate accumulated thereon.

2 more elements

A method of filtering edible oils comprising:

(a) passing a fluid containing solid particulate matter into a first backwashable filter assembly and into a second backwashable filter assembly;
(b) removing the solid particulate matter from the fluid by directing the fluid through at least one filter element in the first backwashable filter assembly, including accumulating a cake of the solid particulate matter on the at least one filter element in the first backwashable filter assembly, and through at least one filter element in the second backwashable filter assembly, including accumulating a cake of the solid particulate matter on the at least one filter element in the second backwashable filter assembly;
wherein said at least one filter element in the first backwashable filter assembly and said at least one filter element in the second backwashable filter assembly comprises a fibrous filter medium having a graded pore structure, including passing the edible oil through a coarser pore upstream region and then a finer pore downstream region;
(c) backwashing the at least one filter element in the first backwashable filter assembly after the cake of solid particulate matter is formed on the at least one filter element of the second backwashable filter assembly;
and
(d) backwashing the at least one filter element in the second backwashable filter assembly after the cake of solid particulate matter is formed on the at least one filter element of the first backwashable filter assembly.

3 more elements

A method of filtering edible oil fluids comprising:

(a) passing an edible oil fluid containing solid particulate matter into an inlet of a first backwashable filter assembly;
(b) removing the solid particulate matter from the fluid by directing the fluid through the at least one filter element in the first backwashable filter assembly, including building a cake of the solid particulate matter on the at least one filter element in the first backwashable filter assembly;
(c) discontinuing passing of the fluid containing solid particulate matter into the inlet of the first backwashable filter assembly;
(d) passing the fluid containing solid particulate matter into an inlet of a second backwashable filter assembly through an outlet of the second backwashable filter assembly and into the inlet of the first backwashable filter assembly;
(e) removing the solid particulate matter from the fluid by directing the fluid through the at least one filter element in the second backwashable filter assembly, including accumulating a cake of the solid particulate matter on the at least one filter element in the second backwashable filter assembly, and through the at least one filter element in the first backwashable filter assembly, and through the cake of the solid particulate matter on the at least one filter element in the first backwashable filter assembly;
(f) discontinuing passing the fluid from the outlet of the second backwashable filter assembly to the inlet of the first backwashable filter assembly;
(g) backwashing the at least one filter element in the first backwashable filter assembly;
(h) discontinuing passing of the fluid containing solid particulate matter into the inlet of the second backwashable filter assembly;
(i) passing the fluid containing solid particulate matter into an inlet of the first backwashable assembly through the outlet of the first backwashable filter assembly and into the inlet of the second backwashable filter assembly;
(j) removing the solid particulate matter from the fluid by directing the fluid through the at least one filter element in the first backwashable filter assembly, including accumulating a cake of the solid particulate matter on the at least one filter element in the first backwashable filter assembly, and through the at least one filter element in the second backwashable filter assembly, including accumulating a cake of the solid particulate matter on the at least one filter element in the second backwashable filter assembly;
(k) discontinuing passing the fluid from the outlet of the first backwashable filter assembly;
and
(l) backwashing the at least one filter element in the second backwashable filter assembly.

10 more elements

Dependencies are inferred from the claim text.

Facts

Application: 08/555,803Filed 9 Nov 1995 · continuation
Priority: 17 Aug 1994
Granted: 13 May 1997
Term ends: Not estimatedThe source records don’t support an estimate.

Classification11 codes

B01D 35/12
Filtering devices having features not specifically covered by groups B01D24/00 - B01D33/00, or for applications not specifically covered by…
B01D 24/002
Filters comprising loose filtering material, i.e. filtering material without any binder between the individual particles or fibres thereof: with…
B01D 24/008
With multiple filtering elements in series connection: arranged concentrically or coaxially
B01D 24/08
The filtering material being clamped between pervious fixed walls: the filtering material being supported by at least two pervious coaxial walls