The pulp & paper industry

Photo: Billerud  

Our control valves and on/off valves have many uses and may therefore be utilized in many different industrial applications. SOMAS valves are mainly designed for use in the paper & pulp industry and naturally adapted to the specific demands of this industry. We have been meticulous in designing these valves, and the result speaks for itself. As regards materials used as well as design, our valves for use in the paper & pulp industry meets the control objectives.

3 types of pulp in the pulp & paper industry

Pulp is divided in three categories:

• Chemical pulp
• Mechanical pulp
• Recycled pulp

The raw material for chemical pulp is pulpwood. This is boiled in order to remove the glue (lignin) between the fibers. After boiling, the pulp is washed and bleached in several steps prior to storage.

Boiling the pulpwood is not the only way to produce pulp. One may choose to grind the pulpwood instead, and in this way produce mechanical pulp. The wood chips pass a number of refining steps before filtering, washing and bleaching.

A third option is using recycled paper as raw material. Recycled paper is fed in a drum where the defibring is performed. Chemicals are added to remove printers ink, pollutants are removed, and the pulp washed and bleached prior to storage.