Patent · US Expired

Two stage counter current drum washer

US6006554A · kind A · utility

15Cited by
25References
10Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 3, 1998
Grant dateDec 28, 1999
Priority date
Expiry dateJun 3, 2018

Classification

  • Technology area (CPC D)Textiles; Paper
  • CPC primaryD21C9/06
  • WIPO fieldTextile and paper machines
  • WIPO sectorMechanical engineering

Abstract

Paper fiber suspended in black liquor is washed in a rotating drum divided into a plurality of adjacent sectors. The fiber is formed into a mat on the drum, and the drum is rotated so the sectors progress through a first wash and a second wash of progressively cleaner wash fluid. Each sector has two distinct drainage systems. One drainage system drains the first wash water after it has passed through the mat, and is then blocked while that sector passes through the second wash. The cleaner second wash fluid is thus kept separate from the more contaminated first wash fluid, and is recirculated to be used in subsequent cycles as first wash fluid.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.