Patent US3897301A successfully refreshed from Google Patents.
US3897301A
Expired / Lapsed
US
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Recovery of papermaking solids for reuse, with an active chlorine-bearing chemical
Assignee: Magnera Corp
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Filing: 1974-04-01
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Granted: 1975-07-29
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Expires: 1994-04-01
Abstract
Abstract Fillers and fine fibers are reclaimed from a paper mill sewer in a process involving dewatering and chemical treatment, using an active chlorine-bearing chemical, such that the drainage rate of the reclaimed fine fibers and filler is vastly improved. The mixture of filler and fine fibers can then be recycled to the paper mill for reuse without a decrease in production rate, as would otherwise occur because of poor drainage of the fine fibers and filler, and without lowering of paper quality. This ability to reuse reclaimed materials comprises an important reduction in environmental pollution and a significant reduction in the waste of raw materials.
Inventors
- 👤 Harry D Bauman
- 👤 Iii L Richmond Lutz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 08:02
CPC Classifications
D; D21; D21F; D21F1/00; D21F1/66; D21F1/82; Y; Y10; Y10S; Y10S162/00; Y10S162/09
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
91 words
THE PROCESS WHICH COMPRISES SEPARATING AN ADMIXTURE OF WATER, LONG FIBERS, FIBER-FINES AND INORGANIC FILLERS FROM THE SEWAGE OF A PAPERMAKING PROCESS, PARTIALLY DEWATERING SAID ADMIXTURE TO A WATER CONTENT OF FROM ABOUT 5 PERCENT TO ABOUT 25 PERCENT SOLIDS, AND REACTING SAID ADMIXTURE AT AMBIENT TEMPERATURE UNDER GENTLE AGITATION FOR FROM ABOUT 4 HOURS TO ABOUT 72 HOURS WITH ENOUGH ACTIVE CHLORINE-BEARING CHEMICAL TO PROVIDE FROM ABOUT 10 TO 50 GRAMS OF ACTIVE CHLORINE PER POUND OF SOLIDS IN SAID ADMIXTURE WHEREBY THE DRAINAGE RATE OF SAID ADMIXTURE IS IMPROVED.
Claim 2
Dependent Claim
91 words
THE PROCESS WHICH COMPRISES SEPARATING AN ADMIXTURE OF WATER, LONG FIBERS, FIBER-FINES AND INORGANIC FILLERS FROM THE SEWAGE OF A PAPERMAKING PROCESS, PARTIALLY DEWATERING SAID ADMIXTURE TO A WATER CONTENT OF FROM ABOUT 5 PERCENT TO ABOUT 25 PERCENT SOLIDS, AND REACTING SAID ADMIXTURE AT AMBIENT TEMPERATURE UNDER GENTLE AGITATION FOR FROM ABOUT 4 HOURS TO ABOUT 72 HOURS WITH ENOUGH ACTIVE CHLORINE-BEARING CHEMICAL TO PROVIDE FROM ABOUT 10 TO 50 GRAMS OF ACTIVE CHLORINE PER POUND OF SOLIDS IN SAID ADMIXTURE WHEREBY THE DRAINAGE RATE OF SAID ADMIXTURE IS IMPROVED.
Claim 3
Dependent Claim
15 words
The process as described in claim 1 wherein said active chlorine-bearing chemical is sodium hypochlorite.
Claim 4
Dependent Claim
21 words
The process as described in claim 1 wherein the long fibers are removed from said admixture before said partial dewatering step.
Claim 5
Dependent Claim
30 words
The process as described in claim 1 wherein said treated admixture is used as part of the furnish or feed in a papermaking machine without the loss of production rate.
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) | 1978-07-28 | 1979-01-27 | 1979-07-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-07-28 | 1983-01-27 | 1983-07-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-07-28 | 1987-01-27 | 1987-07-29 | $7700.00 | Window Closed / Lapsed |