Paper making and fiber liberation – Processes of chemical liberation – recovery or purification... – Treatment with particular chemical
Reexamination Certificate
2007-02-27
2007-02-27
Hug, Eric (Department: 1731)
Paper making and fiber liberation
Processes of chemical liberation, recovery or purification...
Treatment with particular chemical
C162S024000, C162S025000, C162S077000, C162S083000
Reexamination Certificate
active
10482617
ABSTRACT:
The invention relates to a method for delignifying lignocellulosic raw materials by using sulfites in the presence of an alkaline component, especially sodium hydroxide or sodium carbonate or a mixture thereof in an aqueous solution at a high temperature and high pressure. The invention is characterized in that a first partial fragment of the alkaline component is added when the aqueous solution starts to decompose and in that at least a second partial fragment of the alkaline component is added only when delignification begins.
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Kordsachia Othar
Patt Rudolf
Rose Bjorn
Bachman & LaPointe P.C.
Hug Eric
Voith Paper Fiber Systems GmbH KG
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