Patent · US Expired

Process and apparatus for producing pulp

US4451331A · kind A · utility

10Cited by

5References

10Claims

0Family size

Assignee

Simmering-Graz-Pauker Aktiengeselschaft · AT

Inventors

Augustin Raggam · St. Margarethen, AT
Hermann Rabitsch · Mannheim, DE

Key dates

Filing date	Nov 17, 1981
Grant date	May 29, 1984
Priority date	—
Expiry date	Nov 17, 2001

Classification

Technology area (CPC Y)Emerging Cross-Sectional Technologies
CPC primaryY10S162/02
WIPO fieldMachine tools
WIPO sectorMechanical engineering

Abstract

A process and apparatus for producing pulp from impregnated cellulose-containing starting materials such as wood, straw, grass, waste materials etc. in a compacting apparatus comprising a shell (1) and two mutually opposite pistons (4, 4') contained in the shell. The material to be compacted is disposed between the pistons and constitutes a resistive electrical load. The pistons are movable relative to each other and the shell is movable relative to the pistons. The impregnated starting materials are digested at a relatively low hydromodulus of 0.5 to 2 with a direct action of heat on the impregnated starting materials in the compacting apparatus at a digesting temperature of 160.degree. to 300.degree. C. The digesting times are short and depend on the digesting temperature.

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