High defiberization chip pretreatment apparatus
Number of patents in Portfolio can not be more than 2000
United States of America Patent
Stats
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Feb 22, 2011
Grant Date -
Jun 19, 2008
app pub date -
Nov 19, 2007
filing date -
Jul 19, 2002
priority date (Note) -
In Force
status (Latency Note)
Importance
Abstract
A chip pretreatment process which comprises conveying the feed material through a compression screw device having an atmosphere of saturated steam at a pressure above about 5 psig, decompressing and discharging the compressed material from the screw device into a decompression region, feeding the decompressed material from the decompression region into a fiberizing device, such as a low intensity disc refiner, where at least about 30 percent of the fiber bundles and fibers are axially separated, without substantial fibrillation of the fibers. In a more specific form the invention is directed to a process for producing mechanical pulp, including the steps of fiberizing wood chip feed material in a low intensity disc refiner until at least about 30 percent of the fibers are axially separated with less than about 5 percent fibrillation, and subsequently refining the fiberized material in a high intensity disc refiner until at least about 90 percent of the fibers are fibrillated. In another form the invention combines chip fiberizing with chemical treatments, for improving the pulp property versus energy relationships.
First Claim
Other Claims data not available
