Method of producing pulp with high yield using a two-stage refining system operating at different temperatures
AssigneeSunds Defibrator Industries AB
InventorsHans Hoglund, Roland Back, Ove Danielsson
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Abstract
A method of producing mechanical and chemi-mechanical pulp with a yield above 85 % from lignocellulose-containing material for the manufacture of paper or board products. The material is subjected to mechanical processing in at least two steps. The material at its feed into the first step has a temperature below the softening temperature of lignin. When the material is fed into at least one subsequent processing step, it shall have a temperature above the softening temperature of lignin.
Claims21
A method for producing pulp from lignocellulose-containing fibrous material with a yield of greater than about 85% comprising:
- feeding said lignocellulose-containing fibrous material to a first refining step conducted at a first temperature less than the softening temperature of lignin, mechanically processing said lignocellulose-containing fibrous material in said first refining step to produce a first refined lignocellulose-containing fibrous material, feeding said first refined lignocellulose-containing fibrous material to a second refining step conducted at a second temperature greater than the softening temperature of lignin, and mechanically processing said first refined lignocellulose-containing fibrous material in said second refining step to produce said pulp.
Dependencies are inferred from the claim text.