Properties of pulps from different processes

In a pulping process, wood is transformed into fibers. This can be realizedmechanically thermally, chemically or through acombination 

Fiber character Long, strong, collapsed, flexible, stable intermediate pulp properties (some unique properties) Short, impure fibers, unstable, weak, uncollapsed, stiff 

Examples Kraft Sulfite Soda Neutral sulfite semichemical High-yield Kraft High-yield sulfite Stone groundwood Refiner mechanical pulp Thermomechanical pulp 

In chemical pulping, the objective is to degrade and dissolve away the lignin and to leave behind most of the cellulose and hemicellulose, i.e., fibers. Chemical pulp is produced by chemical pulping of vegetable raw materials such as hardwood and 

The two main procedures are the Kraft process and the sulfite process. Kraft cooking (alkaline) is the parent chemical pulping method globally. Sulfite process (acidic) makes the lignin water-soluble. Chemical pulp fibers are more flexible than mechanical pulp fibers. Chemical pulps give paper good strength qualities. 

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