Patent US3518837A successfully refreshed from Google Patents.
Patent US3595038A successfully refreshed from Google Patents.
US3595038A
Expired / Lapsed
US
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Apparatus for washing fibrous suspensions
Assignee: Svenska Cellulosa AB
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Filing: 1968-06-14
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Granted: 1971-07-27
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Expires: 1988-06-14
Abstract
Abstract In washing paper pulp or similar fibrous suspension the suspension is moved intermittently vertically through a column. In the dwell periods, washing liquid is forced through the fibrous suspension, and the resulting ''''extract'''' removed, in a generally horizontal direction through perforate screening members forming portions of the column.
Inventors
- 👤 Carl Arne Bergholm
- 👤 Per-Erik Ankersson
- 👤 Gustaf Rune Hellerqvist
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 20:07
CPC Classifications
D; D21; D21C; D21C9/00; D21C9/02; D21C9/04
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
52 words
An apparatus according to claim 1 wherein the means for intermittently feeding the suspension through the washing zone to provide alternating dwell and movement periods comprises a movable disc disposed transversely of the main axis of the washing column so as to form a substantial seal with the walls of aid column.
Claim 2
Dependent Claim
39 words
An apparatus according to claim 1 wherein the pressure gradient applying means comprises a liquid-containing vessel having means for regulating the level of liquid therein and means connecting said vessel to the washing zone via the extract screen element.
Claim 3
Dependent Claim
55 words
An apparatus according to claim 1, wherein the means for preventing excessive speed of the suspension through the column and ensuring that the suspension remains stationary between the screening elements during said dwell periods, is in the form of at least one baffle means located in the close proximity of the fiber suspension outlet means.
Claim 4
Dependent Claim
57 words
An apparatus according to claim 1, wherein said washing cylinder is cylindrical and further comprising a plurality of perforated screen elements for introducing wash liquid, a plurality of extract withdrawal perforated screen elements, said screen elements being cylindrical and arranged in spaced relation alternately with respect to each other and coaxially with respect to said cylindrical column.
Claim 5
Dependent Claim
50 words
An apparatus according to claim 1 in which said washing column extends vertically and the suspension is moved vertically downwardly therethrough, wherein means are provided for preventing downward movement of the suspension disposed between said means for introducing a wash liquid and said perforated screen element during said dwell periods.
References Cited (Backward Citations)
US439033A
Cited
GB150782A
Cited
US1864220A
Cited
US3088306A
Cited
US3078703A
Cited
US3372087A
Cited
US3425898A
Cited
US3475271A
Cited
US3385753A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-07-26 | 1975-01-25 | 1975-07-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-07-26 | 1979-01-25 | 1979-07-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-07-26 | 1983-01-25 | 1983-07-27 | $7700.00 | Window Closed / Lapsed |