Claims
- 1. An apparatus for treating pulp, comprising:
- a first bleaching tower for bleaching pulp;
- a post-screening treatment device including at least one of a washer, a thickener, a dryer and a second bleaching tower;
- a screener in fluid communication with said first bleaching tower and said post-screening treatment device, said screener including a pressure screen for generating from the pulp exiting said bleaching tower a first reject fraction and a first accept fraction, such that said first accept fraction is supplied to one of said post-screening treatment devices without further treatment by a separate thickener; and
- a vortex cleaner including means for generating from said first reject fraction a second reject fraction and a second accept fraction, said vortex cleaner being connected with one of said screener and said post-screening treatment device such that said second accept fraction is supplied to one of said screener and said post-screening treatment device without further treatment by a separate thickener.
- 2. The apparatus of claim 1, wherein said post-screening treatment device is a washer and said pressure screen is disposed downstream said first bleaching tower and upstream said washer.
- 3. The apparatus of claim 1, wherein said post-screening treatment device is a dryer and said pressure screen is disposed downstream said first bleaching tower and upstream said dryer.
- 4. The apparatus of claim 1, wherein said pressure screen comprises a rotatable rotor and a screen drum surrounding said rotor.
- 5. The apparatus of claim 4, wherein a surface of said screen drum facing said rotor defines a plurality of grooves, said grooves being perpendicular to a flow direction of the pulp.
- 6. The apparatus of claim 5, wherein each of said plurality of grooves has a bottom surface defining a narrow slot extending through said screen drum.
- 7. The apparatus of claim 6, wherein each of said plurality of narrow slots has a width that is less than 0.25 mm.
Priority Claims (1)
Number |
Date |
Country |
Kind |
922635 |
Jun 1992 |
FIX |
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Parent Case Info
This is a division of application Ser. No. 08/073,793, filed Jun. 8, 1993, now U.S. Pat. No. 5,470,432.
US Referenced Citations (4)
Foreign Referenced Citations (4)
Number |
Date |
Country |
1102604 |
Jun 1991 |
CAX |
781789 |
Jun 1978 |
FIX |
77276 |
Feb 1989 |
FIX |
465781 |
Sep 1989 |
SEX |
Divisions (1)
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Number |
Date |
Country |
Parent |
73793 |
Jun 1993 |
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