Granted Patent
Utility
US 6,139,689 · App. 08/872,711
Apparatus for digesting pulp in a displacement batch digester that uses displacement liquor having a sufficient hydrostatic head
Inventors:
Jeremiah W. Polston, Raymond J. Pitre, Helmut Böhm
Patented Case
View Patent ↗
Granted: Oct 31, 2000
Filed: Jun 11, 1997
Inventors
Jeremiah W. Polston
Raymond J. Pitre
Helmut Böhm
Assignee (at issue)
Beloit Technologies, Inc.
This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.