US3873418A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of recovering noil fibres and soluble wood material from waste water
Assignee: SAVO Oy
•
Filing: 1972-02-29
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Granted: 1975-03-25
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Expires: 1992-02-29
Abstract
Abstract Noil fibres and wood material which has dissolved or is becoming dissolved in white water from wood processing industries are recovered and used as additional raw material, and resulting clarified water is recycled for use as fabrication water. The pH of water is controlled during the recovery process and the material to be recovered is caused to agglomerate by the addition of agents whose presence in the final product is beneficial. A polyelectrolyte or the like can be added to enhance flock formation.
Inventors
- 👤 Esko Kai Brax
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 15:42
CPC Classifications
D; D21; D21F; D21F1/00; D21F1/66; Y; Y10; Y10S; Y10S210/00; Y10S210/928
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
206 words
A METHOD OF RECOVERING NOIL FIBRES AND SOLUBLE WOOD MATERIAL IN WHITE WATER FROM A MANUFACTURING PROCESS INVOLVING THE FORMATION OF A PULP WEB BY SEPARATING FLOCKED OUT MATERIAL FROM WATER TO PRODUCE CLEARED WATER AND RETURNING THE MATERIAL FLOCKED OUT TO THE PULP WEB FOR RETENTION AS A BENEFICIAL CONSTITUENT OF THE MANUFACTURED PRODUCT, COMPRISING: ADDING A SUFFICIENT QUANTITY OF AN ALKALINE SUBSTANCE TO WHITE WATER TO PREVENT PREMATURE COAGULATING OF SUSPENDED MATERIAL; THEN ADDING AS A COAGULATING AGENT A MATERIAL WHOSE PRESENCE IN THE PULP WEB FORMED IS BENEFICIAL SELECTED FROM THE GROUP CONSISTING OF PHENOL-FORMALDEHYDE RESIN, CARBOXYMETHYLCELLULOSE, UREA RESIN, MELAMINE, LINSEED OIL EMULSION; POLYVINYLCHLORIDE-LATEX EMULSION AND ACRYLIC LATEX EMULSION; THROUGHLY MIXING SAID WHITE WATER WITH SAID COAGULATING AGENT TO OBTAIN A SUBSTANTIALLY HOMOGENEOUS SUSPENSION; AFTER SAID MIXING, ADDING A SUFFICIENT QUANTITY OF AN ACIDIC SUBSTANCE TO THE SUSPENSION TO LOWER THE PH TO FORM FLOCKS INCORPORATING SAID COAGULATING AGENT, NOIL FIBRES AND SOLUBLE WOOD MATERIAL FROM THE WHITE WATER; SEPARATING WATER FROM SAID FLOCKS BY GRAVITY SEPARTION TO OBTAIN CLEARED WATER AND RECYCLING MOST OF THE CLEARED WATER FOR USE IN MANUFACTURING PROCESSES; AND RETURNING THE FLOCKS TO THE PULP WEB TO FORM CONSTITUENT MATERIAL IN THE FINAL PRODUCT OF THE MANUFACTURING PROCESS.
Claim 2
Independent Claim
206 words
A METHOD OF RECOVERING NOIL FIBRES AND SOLUBLE WOOD MATERIAL IN WHITE WATER FROM A MANUFACTURING PROCESS INVOLVING THE FORMATION OF A PULP WEB BY SEPARATING FLOCKED OUT MATERIAL FROM WATER TO PRODUCE CLEARED WATER AND RETURNING THE MATERIAL FLOCKED OUT TO THE PULP WEB FOR RETENTION AS A BENEFICIAL CONSTITUENT OF THE MANUFACTURED PRODUCT, COMPRISING: ADDING A SUFFICIENT QUANTITY OF AN ALKALINE SUBSTANCE TO WHITE WATER TO PREVENT PREMATURE COAGULATING OF SUSPENDED MATERIAL; THEN ADDING AS A COAGULATING AGENT A MATERIAL WHOSE PRESENCE IN THE PULP WEB FORMED IS BENEFICIAL SELECTED FROM THE GROUP CONSISTING OF PHENOL-FORMALDEHYDE RESIN, CARBOXYMETHYLCELLULOSE, UREA RESIN, MELAMINE, LINSEED OIL EMULSION; POLYVINYLCHLORIDE-LATEX EMULSION AND ACRYLIC LATEX EMULSION; THROUGHLY MIXING SAID WHITE WATER WITH SAID COAGULATING AGENT TO OBTAIN A SUBSTANTIALLY HOMOGENEOUS SUSPENSION; AFTER SAID MIXING, ADDING A SUFFICIENT QUANTITY OF AN ACIDIC SUBSTANCE TO THE SUSPENSION TO LOWER THE PH TO FORM FLOCKS INCORPORATING SAID COAGULATING AGENT, NOIL FIBRES AND SOLUBLE WOOD MATERIAL FROM THE WHITE WATER; SEPARATING WATER FROM SAID FLOCKS BY GRAVITY SEPARTION TO OBTAIN CLEARED WATER AND RECYCLING MOST OF THE CLEARED WATER FOR USE IN MANUFACTURING PROCESSES; AND RETURNING THE FLOCKS TO THE PULP WEB TO FORM CONSTITUENT MATERIAL IN THE FINAL PRODUCT OF THE MANUFACTURING PROCESS.
Claim 3
Dependent Claim
13 words
The method of claim 1 wherein the acidic substance is a metallic salt.
Claim 4
Dependent Claim
51 words
The method of claim 1 and including separating the cleared water into two fractions, one fraction being recycled and used as fabrication water, the other fraction being discharged to a recipient, and wherein the amount of water discharged is only that necessary to maintain the water balance of the manufacturing process.
Claim 5
Dependent Claim
28 words
The method of claim 1 wherein such quantities of said alkaline substance and of said acidic substance are added that said flock formation occurs near the isoelectric point.
Claim 6
Dependent Claim
22 words
The method of claim 1 and including the addition of a polyelectrolyte for fine regulation of total charges on the suspended materials.
Claim 7
Independent Claim
205 words
A method of recovering noil fibres and soluble wood material in white water from a manufacturing process involving the formation of a pulp web by separating flocked out material from water to produce cleared water and returning the material flocked out to the pulp web for retention as a beneficial constituent of the manufactured product, comprising: adding a sufficient quantity of an acidic substance to white water to prevent premature coagulation of suspended material; then adding as a coagula-agent a meterial whose presence in the pulp web formed is beneficial selected from the group consisting of phenoformaldehyde resin, carboxymethylcellulose, urea resin, melamine, linseed oil emulsion, polyvinylchloride-latex emulsion and acrylic latex emulsion; thoroughly mixing said white water with said coagulating agent to obtain a substantially homogeneous suspension; after said mixing, adding a sufficient quantity of an alkaline substance to the suspension to raise the pH to form flocks incorporating said coaGulating agent, noil fibres and soluble wood material from the white water; separating water from said flocks by gravity separation to obtain cleared water and recycling most of the cleared water for use in manufacturing processes; and returning the flocks to the pulp web to form constituent material in the final product of the manufacturing process.
Claim 8
Independent Claim
205 words
A method of recovering noil fibres and soluble wood material in white water from a manufacturing process involving the formation of a pulp web by separating flocked out material from water to produce cleared water and returning the material flocked out to the pulp web for retention as a beneficial constituent of the manufactured product, comprising: adding a sufficient quantity of an acidic substance to white water to prevent premature coagulation of suspended material; then adding as a coagula-agent a meterial whose presence in the pulp web formed is beneficial selected from the group consisting of phenoformaldehyde resin, carboxymethylcellulose, urea resin, melamine, linseed oil emulsion, polyvinylchloride-latex emulsion and acrylic latex emulsion; thoroughly mixing said white water with said coagulating agent to obtain a substantially homogeneous suspension; after said mixing, adding a sufficient quantity of an alkaline substance to the suspension to raise the pH to form flocks incorporating said coaGulating agent, noil fibres and soluble wood material from the white water; separating water from said flocks by gravity separation to obtain cleared water and recycling most of the cleared water for use in manufacturing processes; and returning the flocks to the pulp web to form constituent material in the final product of the manufacturing process.
References Cited (Backward Citations)
US1672584A
Cited
US2771823A
Cited
US2980609A
Cited
US2937143A
Cited
US3130167A
Cited
US3165465A
Cited
US3516932A
Cited
US3171801A
Cited
US3256141A
Cited
US3262877A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-03-24 | 1978-09-23 | 1979-03-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-24 | 1982-09-23 | 1983-03-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-24 | 1986-09-23 | 1987-03-25 | $7700.00 | Window Closed / Lapsed |