US4238334A
Expired / Lapsed
US
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Purification of liquids with treated filter aid material and active particulate material
Assignee: Ecodyne Corp
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Filing: 1979-09-17
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Granted: 1980-12-09
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Expires: 1999-09-17
Abstract
Abstract A method and filter bed for removing impurities from liquids wherein the filter bed comprises a mixture of treated filter aid material and an active particulate material having opposite surface charges in aqueous suspension. The filter aid material has been treated to produce the desired surface charge. The identity of the active particulate material depends on the application. Examples are organic polymeric absorbents, zeolites, bentonite, zirconium oxide, zirconium phosphate, activated alumina, ferrous sulfide, activated carbon and diatomaceous earth.
Inventors
- 👤 Christopher J. Halbfoster
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 22:20
CPC Classifications
B; B01; B01D; B01D37/00; B01D37/02; B01D37/03
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
102 words
A method for removing impurities from a liquid comprising: passing said liquid through a filter bed comprising a mixture of treated fibrous filter aid material and an active particulate material, said treated filter aid material and said particulate material having opposite surface charges in aqueous suspension, and said mixture producing a clumping phenomenon, wherein said filter aid material comprises about 5 to 95% by weight, of said bed, and wherein said filter aid material has been treated with an electrolyte-type compound that produces a surface charge opposite to the normal surface charge by bonding to the surface of said filter aid material.
Claim 2
Independent Claim
102 words
A method for removing impurities from a liquid comprising: passing said liquid through a filter bed comprising a mixture of treated fibrous filter aid material and an active particulate material, said treated filter aid material and said particulate material having opposite surface charges in aqueous suspension, and said mixture producing a clumping phenomenon, wherein said filter aid material comprises about 5 to 95% by weight, of said bed, and wherein said filter aid material has been treated with an electrolyte-type compound that produces a surface charge opposite to the normal surface charge by bonding to the surface of said filter aid material.
Claim 3
Dependent Claim
37 words
The method as defined in claim 1 wherein said active particulate material is selected from the group consisting of organic polymeric absorbants, zeolites, bentonite, zirconium oxide, zirconium phosphate, activated alumina, ferrous sulfide, activated carbon, and diatomaceous earth.
Claim 4
Dependent Claim
35 words
The method as defined in claim 2 wherein said filter aid material is selected from the group consisting of cellulose fibers, polyacrylonitrile fibers, Teflon fibers, nylon fibers, rayon fibers, polypropylene fibers, and polyvinyl chloride fibers.
Claim 5
Dependent Claim
26 words
The method as defined in claim 3 wherein the fibers of said filter aid material have an average length of from about 10 to 1000 microns.
Claim 6
Dependent Claim
15 words
The method as defined in claim 1 wherein said active particulate material is activated carbon.
Claim 7
Dependent Claim
44 words
The method as defined in claim 1 wherein said filter aid material has been further treated with a second electrolyte-type compound to produce an enhanced surface charge which is the same as said normal surface charge by bonding to said treated filter aid material.
Claim 8
Dependent Claim
20 words
The method as defined in claim 6 wherein said filter aid material normally has a negative charge in aqueous suspension.
Claim 9
Dependent Claim
21 words
The method as defined in claim 7 wherein said cellulose fibers comprise about 25 to 60%, by weight, of said bed.
Claim 10
Dependent Claim
16 words
The method as defined in claim 6 wherein said electrolyte-type compound is a cationic organic polyelectrolyte.
Claim 11
Independent Claim
82 words
A method for removing impurities from a liquid comprising: passing said liquid through a filter bed comprising a mixture of treated cellulose fibers and activated carbon particles, said carbon particles having a negative surface charge, and said mixture producing a clumping phenomenon, wherein said cellulose fibers comprise about 5 to 95%, by weight, of said bed, and wherein said cellulose fibers have been treated with an electrolyte-type compound that produces a positive surface charge by bonding to the surface of said fibers.
Claim 12
Independent Claim
82 words
A method for removing impurities from a liquid comprising: passing said liquid through a filter bed comprising a mixture of treated cellulose fibers and activated carbon particles, said carbon particles having a negative surface charge, and said mixture producing a clumping phenomenon, wherein said cellulose fibers comprise about 5 to 95%, by weight, of said bed, and wherein said cellulose fibers have been treated with an electrolyte-type compound that produces a positive surface charge by bonding to the surface of said fibers.
Claim 13
Dependent Claim
90 words
An improved filter bed comprising a mixture of treated fibrous filter aid material and an active particulate material, said treated filter aid material and said particulate material having opposite surface charges in aqueous suspension, and said mixture producing a clumping phenomenon, wherein said filter aid material comprises about 5 to 95% by weight, of said bed, and wherein said filter aid material has been treated with an electrolyte-type compound that produces a surface charge opposite to the normal surface chharge by bonding to the surface of said filter aid material.
Claim 14
Dependent Claim
90 words
An improved filter bed comprising a mixture of treated fibrous filter aid material and an active particulate material, said treated filter aid material and said particulate material having opposite surface charges in aqueous suspension, and said mixture producing a clumping phenomenon, wherein said filter aid material comprises about 5 to 95% by weight, of said bed, and wherein said filter aid material has been treated with an electrolyte-type compound that produces a surface charge opposite to the normal surface chharge by bonding to the surface of said filter aid material.
Claim 15
Dependent Claim
38 words
The filter bed as defined in claim 11 wherein said active particulate material is selected from the group consisting of organic polymeric absorbants, zeolites, bentonite, zirconium oxide, zirconium phosphate, activated alumina, ferrous sulfide, activated carbon, and diatomaceous earth.
Claim 16
Dependent Claim
36 words
The filter bed as defined in claim 12 wherein said filter aid material is selected from the group consisting of cellulose fibers, polyacrylonitrile fibers, Teflon fibers, nylon fibers, rayon fibers, polypropylene fibers, and polyvinyl chloride fibers.
Claim 17
Dependent Claim
21 words
The filter bed as defined in claim 13 wherein said fibers have an average length of about 10 to 1000 microns.
Claim 18
Dependent Claim
16 words
The filter bed as defined in claim 11 wherein siad active particulate material is activated carbon.
Claim 19
Dependent Claim
45 words
The filter bed as defined in claim 11 wherein said filter aid material has been further treated with a second electrolyte-type compound to produce an enhanced surface charge which is the same as said normal surface charge by bonding to said treated filter aid material.
Claim 20
Dependent Claim
21 words
A filter bed as defined in claim 16 wherein said filter aid material normally has a negative charge in aqueous suspension.
Claim 21
Dependent Claim
71 words
An improved filter bed comprising: a mixture of treated cellulose fibers and activated carbon particles, said carbon particles having a negative surface charge, and said mixture producing a clumping phenomenon, wherein said cellulose fibers comprise about 5 to 95%, by weight, of said bed, and wherein said cellulose fibers have been treated with an electrolyte-type compound that produces a positive surface charge by bonding to the surface of said cellulose fibers.
Claim 22
Dependent Claim
71 words
An improved filter bed comprising: a mixture of treated cellulose fibers and activated carbon particles, said carbon particles having a negative surface charge, and said mixture producing a clumping phenomenon, wherein said cellulose fibers comprise about 5 to 95%, by weight, of said bed, and wherein said cellulose fibers have been treated with an electrolyte-type compound that produces a positive surface charge by bonding to the surface of said cellulose fibers.
Claim 23
Dependent Claim
17 words
The filter bed as defined in claim 18 wherein said electrolyte-type compound is a cationic organic polyelectrolyte.
Claim 24
Dependent Claim
22 words
The filter bed as defined in claim 19 wherein said cellulose fibers comprise about 25% to 60%, by weight, of said bed.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-12-09 | 1984-06-09 | 1984-12-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-12-09 | 1988-06-09 | 1988-12-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-12-09 | 1992-06-09 | 1992-12-09 | $7700.00 | Window Closed / Lapsed |