US3849247A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Screening and feeding device for cellulose digesters
Assignee: Metso Fiber Karlstad AB
•
Filing: 1973-03-12
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Granted: 1974-11-19
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Expires: 1993-03-12
Abstract
Abstract A cellulose digesting apparatus having at least one vertical digester in open communication with a pressure-resistant vessel containing a screening device, the screening device comprising a shell having an upper impervious portion and a lower strainer portion, wherein liquid is strained from a chips-liquid suspension for recirculation of the liquid, and a feeding device which is adapted to transfer the chips from said vessel to the digester, around the shell a circular trough for collecting chips discharged over the top edge of the impervious portion, the feeding device comprising a plurality of chips outlets in the vessel each adapted for connection to a separate digester and a distributing device for the distribution of the chips upon the outlets used.
Inventors
- 👤 J Richter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 22:25
CPC Classifications
D; D21; D21C; D21C7/00; D21C7/06
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
198 words
A cellulose digesting apparatus in which a top portion of at least one vertical digester is in open communication with a pressure-resistant vessel containing a screening device wherein liquid is strained from a chips-liquid suspension for recirculation of the liquid, and a feeding device for transferring the chips from said vessel to the digester, said feeding device comprising a plurality of chips outlets in the vessel each for connection to a separate digester and a distributing device for the distribution of the chips upon the outlets used, said screening device comprising a separating shell having an upper impervious portion and a lower strainer portion including means for collecting liquid separated from the chips; means for feeding the strainer chips upwardly through the shell for discharge over the top edge of the upper impervious portion, said means including a feeder screw surrounded by said shell and coaxial therewith; collecting means around said shell and below the top edge of said impervious portion for collecting strained chips discharged therefrom, said collecting means comprising a circular trough; the chips outlets comprising tubes connected to and sloping downwardly from the bottom of said trough for discharge into said digestors substantially by gravity.
Claim 2
Dependent Claim
198 words
A cellulose digesting apparatus in which a top portion of at least one vertical digester is in open communication with a pressure-resistant vessel containing a screening device wherein liquid is strained from a chips-liquid suspension for recirculation of the liquid, and a feeding device for transferring the chips from said vessel to the digester, said feeding device comprising a plurality of chips outlets in the vessel each for connection to a separate digester and a distributing device for the distribution of the chips upon the outlets used, said screening device comprising a separating shell having an upper impervious portion and a lower strainer portion including means for collecting liquid separated from the chips; means for feeding the strainer chips upwardly through the shell for discharge over the top edge of the upper impervious portion, said means including a feeder screw surrounded by said shell and coaxial therewith; collecting means around said shell and below the top edge of said impervious portion for collecting strained chips discharged therefrom, said collecting means comprising a circular trough; the chips outlets comprising tubes connected to and sloping downwardly from the bottom of said trough for discharge into said digestors substantially by gravity.
Claim 3
Dependent Claim
35 words
Apparatus according to claim 1 wherein the distributing device comprises one or more scraper arms extending radially beyond the separating shell into the circular trough and being attached to and driven with the feeder screw.
Claim 4
Dependent Claim
28 words
Apparatus according to claim 2 wherein the outlets are varied with respect to position about the trough so as to vary proportions of chips input into said outlets.
Claim 5
Dependent Claim
34 words
Apparatus according to claim 1, which further includes an impregnation vessel coupled to the pressure-resistant vessel which is adapted to impregnate the chips therein with digesting liquor at essentially the pressure of the digester.
Claim 6
Dependent Claim
74 words
Apparatus according to claim 4 wherein said distributing device comprises a first scraper and wherein the lower portion of the pressure-resistant vessel has a lower opening therein and the impregnation vessel includes a frusto-conical section coupled to the pressure-resistant vessel at its lower opening; the tOp of the impregnation vessel has a second scraper in the frusto-conical section which includes radially extending arms coupled at a center hub and driven by the feeder screw.
Claim 7
Dependent Claim
26 words
Apparatus according to claim 1 further comprising means for varying the size of the chips outlets to effect a desired distribution of chips to chips outlets.
References Cited (Backward Citations)
US2459180A
Cited
US3041232A
Cited
US2969113A
Cited
US3471366A
Cited
US3294626A
Cited
US3467573A
Cited
US3586600A
Cited
US3681192A
Cited
US3743572A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-11-18 | 1978-05-20 | 1978-11-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-11-18 | 1982-05-20 | 1982-11-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-11-18 | 1986-05-20 | 1986-11-19 | $7700.00 | Window Closed / Lapsed |