Patent EP0203713A2 successfully refreshed from Google Patents.
EP0203713A2
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EP
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High flow electrofiltration
Assignee: Dorr Oliver Inc
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Filing: 1986-04-24
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Granted: —
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Expires: 2006-04-24
Abstract
Abstract An electrically augmented crossflow filter device in which a feed stream containing solid particulate matter is flowed between opposed walls while a pressure differential is imposed across a first of said walls 23 comprising a filter medium to produce a flow of filtrate therethrough in a direction perpendicular to the direction of flow of the feed stream. At the same time, an electric field is imposed on the feed stream in a direction perpendicular to the direction 18 of the flow of the feed stream, causing the solid particulate matter in the feed stream to tend to move toward the second of said walls which comprises an ion-pervious member 77. Cake formation on the latter ion-pervious wall is limited or precluded by the velocity of the feed stream while the feed stream thickens in passing between the walls to form the product stream 17. The electrode which is located behind the second, or ion-pervious, wall is immersed during operation in a protective stream of a selected electrolyse.
Inventors
- 👤 James M. Bollinger
- 👤 Peter R. Klinkowski
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-31 15:55
CPC Classifications
B; B01; B01D; B01D57/00; B01D57/02; B01D29/00; B01D29/39; B01D29/88; B01D29/94; B01D29/945; B01D35/00; B01D35/06
Claims Analysis
Total Claims: 29
Claim 1
Independent Claim
193 words
An electrically augmented crossflow filter device for dewatering a slurry comprising a housing, a narrow, elongated feed-product channel within said housing, a feed inlet at one extremity of said feed-product channel, a product outlet at the other extremity of said feed-product channel, said feed-product channel defined in part by a pair of opposed walls, a filtrate channel lying parallel to said feed-product channel and contiguous with a first of said walls, said first wall comprising a filter medium, an electrode element of a first polarity in said filtrate channel, a filtrate outlet for withdrawing filtrate from said filtrate channel, an electrolyte channel lying parallel to said feed-product channel and contiguous with the second of said walls, said second wall comprising an ion-pervious member, an electrode element of a second polarity in said electrolyte channel, means for passing an electrolyte solution through said electrolyte channel to immerse said electrode element therein in a flowing stream of electrolyte, means for establishing a pressure differential between said feed-product channel and said filtrate channel across said first wall and means for establishing an electric field perpendicular to the axis of said feed-product channel between said electrode elements.
Claim 2
Dependent Claim
193 words
An electrically augmented crossflow filter device for dewatering a slurry comprising a housing, a narrow, elongated feed-product channel within said housing, a feed inlet at one extremity of said feed-product channel, a product outlet at the other extremity of said feed-product channel, said feed-product channel defined in part by a pair of opposed walls, a filtrate channel lying parallel to said feed-product channel and contiguous with a first of said walls, said first wall comprising a filter medium, an electrode element of a first polarity in said filtrate channel, a filtrate outlet for withdrawing filtrate from said filtrate channel, an electrolyte channel lying parallel to said feed-product channel and contiguous with the second of said walls, said second wall comprising an ion-pervious member, an electrode element of a second polarity in said electrolyte channel, means for passing an electrolyte solution through said electrolyte channel to immerse said electrode element therein in a flowing stream of electrolyte, means for establishing a pressure differential between said feed-product channel and said filtrate channel across said first wall and means for establishing an electric field perpendicular to the axis of said feed-product channel between said electrode elements.
Claim 3
Dependent Claim
20 words
The electrically augmented crossflow filter device of claim 1 wherein the first of said walls is an anisotropic polymeric membrane.
Claim 4
Dependent Claim
18 words
The electrically augmented crossflow filter device of claim 2 wherein said anisotropic polymeric membrane is a polysulfone membrane.
Claim 5
Dependent Claim
18 words
The electrically augmented crossflow filter device of claim 2 wherein said anisotropic polymeric membrane is a cellulosic membrane.
Claim 6
Dependent Claim
21 words
The electrically augmented crossflow filter device of claim 1 wherein the first of said walls is a cloth fabric filter medium.
Claim 7
Dependent Claim
16 words
The electrically augmented crossflow filter device of claim 5, said cloth fabric being woven dynel cloth.
Claim 8
Dependent Claim
19 words
The electrically augmented crossflow filter device of claim 1 wherein the first of said walls is a microporous membrane.
Claim 9
Dependent Claim
22 words
The electrically augmented crossflow filter device of claim 7 wherein said microporous membrane is a stainless steel, ceramic or polymeric microporous medium.
Claim 10
Dependent Claim
35 words
The electrically augmented crossflow filter device of claim 1 wherein the first of said walls is subject to vacuum applied to said filtrate outlet, said vacuum acting to withdraw said filtrate from said filtrate channel.
Claim 11
Dependent Claim
23 words
The electrically augmented crossflow filter device of claim 1 wherein the second of said walls comprises a substantially hydraulically impermeable ion pervious membrane.
Claim 12
Dependent Claim
20 words
The electrically augmented crossflow filter device of claim 1 wherein the second of said walls is an ion exchange membrane.
Claim 13
Dependent Claim
25 words
The electrically augmented crossflow filter device of claim 11 wherein said ion exchange membrance is a cationic membrane, allowing the passage substantially only of cations.
Claim 14
Dependent Claim
27 words
The electrically augmented cr - ossflow filter device of claim 11 wherein said ion exchange membrane is an anionic membrane, allowing the passage substantially only of anions.
Claim 15
Dependent Claim
26 words
The electrically augmented crossflow filter device of claim 11 wherein said ion exchange membrane is non-selective, said membrane allowing the passage of both anions and cations.
Claim 16
Dependent Claim
17 words
The electrically augmented crossflow filter device of claim 11, wherein said ion exchange membrane is hydraulically permeable.
Claim 17
Dependent Claim
103 words
A process for dewatering a slurry in the electrically augmented crossflow device of claim 1 comprising pumping slurry into said feed-product channel, maintaining a velocity of said slurry in said feed-product channel sufficient to inhibit deposition of solids from said slurry on the walls of said channel, establishing an electric field perpendicular to the axis of said feed product channel between the opposed electrode elements located in said filtrate channel and said electrolyte channel, withdrawing filtrate, continuously circulating electrolyte through said electrolyte channel whereby the electrode therein is immersed in electrolyte and withdrawing a slurry enriched in solids content from said feed-product channel.
Claim 18
Dependent Claim
23 words
The process of claim 16 wherein the velocity of said slurry in said feed-product channel is from about 1 to about 20 ft/sec.
Claim 19
Dependent Claim
24 words
The process of claim 17 wherein the current density due to the applied field is between about 0.1 and about 135 amps/ft 2 .
Claim 20
Dependent Claim
13 words
The process of claim 16 wherein vacuum is applied to said filtrate channel.
Claim 21
Dependent Claim
18 words
The process of claim 16 wherein the solids have an average particle size of less than 100 microns.
Claim 22
Dependent Claim
18 words
The process of claim 16 wherein the solids have an average particle size of less than 10 microns.
Claim 23
Dependent Claim
25 words
The process of claim 16 wherein a dispersant is added to the suspension of solids to prevent plugging of the channel between adjacent electrode assemblies.
Claim 24
Dependent Claim
23 words
The process of claim 16 wherein dispersant is incorporated in said anolyte and is electroosmotically pumped with said anolyte into the feed-product channel.
Claim 25
Dependent Claim
16 words
The process of claim 16 wherein the solids of said slurry have a positive surface charge.
Claim 26
Dependent Claim
17 words
The process of claim 16 wherein the suspended solids of said slurry have a negative surface charge.
Claim 27
Dependent Claim
42 words
The process of claim 16, wherein the suspended solids of said slurry is at least one selected from the group consisting of kaolin, PVC, fine coal, alumina, T 1 0 2 , calcium carbonate, humate, magnesium aluminum hydroxide, and other polymer latexs.
Claim 28
Dependent Claim
45 words
A treatment system for producing a dry powder product comprising the electrically augmented crossflow filter device of claim 1 with the addition of a spray drying station and means for feeding the thickened product slurry of said crossflow filter device to said spray drying station.
Claim 29
Dependent Claim
21 words
The electrically augmented crossflow filter device of claim 5, wherein a protective screen is placed over said cloth fabric filter medium.
References Cited (Backward Citations)
No citation records indexed.
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