Patent · US Expired

Two-stage oxygen pulping

US4080248A · kind A · utility

0Cited by
5References
7Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 28, 1976
Grant dateMar 21, 1978
Priority date
Expiry dateJun 28, 1996

Classification

  • Technology area (CPC D)Textiles; Paper
  • CPC primaryD21C3/263
  • WIPO fieldTextile and paper machines
  • WIPO sectorMechanical engineering

Abstract

The pulping of lignocellulosic material in the presence of oxygen gas and an alkaline liquid is improved by carrying out the process in two stages. In the first stage, the alkaline liquid is trickled over the material as the oxygen is passed up through the material. In the second stage, the material is submerged in oxygenated alkaline liquid which flows through the material.

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