05181989 is referenced by 13 patents and cites 67 patents.

An apparatus for delignifying and bleaching a lignocellulosic pulp without the use of elemental chlorine. The bleaching reactor is a horizontal vessel having a central rotatable shaft which preferably contains paddles, cut and folded screw flights or a ribbon flight, to disperse and advance the pulp particles in a plug flow manner while contacting and mixing the pulp particles with a gaseous bleaching agent such as ozone for substantially uniform bleaching thereof.

Title
Reactor for bleaching high consistency pulp with ozone
Application Number
7/604849
Publication Number
5181989
Application Date
October 26, 1990
Publication Date
January 26, 1993
Inventor
William H Friend
Savannah
GA, US
Thomas P Gandek
Trenton
NJ, US
Michael A Pikulin
Bound Brook
NJ, US
David E White
Pennington
NJ, US
Agent
Pennie & Edmonds
Assignee
Union Camp Patent Holdings
NJ, US
IPC
D21C 9/153
D21C 7/00
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