How is pulp made?
Pulp is truly a versatile bioproduct manufactured from renewable wood raw material. Modern pulp production is based on the best available technology and the philosophy to create more with less raw materials, water, energy and environmental impact.
How do we make pulp?
1. Wood handling
Sustainably grown and sourced wood is first debarked and cut into small chips for more efficient pulping. In addition to wood chips we use sawdust from sawmills and plywood mills for pulp making. The bark of trees is used for bioenergy production at the mill.
2. Fibre processing
The process for both hardwood and softwood is nearly identical, the only difference being the structure of the wood. Softwood consists mostly of cellulose and lignin, and it contains less hemicellulose than hardwood.
Cooking the wood chips in the presence of sodium hydroxide and sulfide liquor under high pressure removes the lignin and separates the wood into cellulose fibres. During the cooking process approximately half the wood dissolves. The pulp is then washed, screened for quality and bleached.
The spent cooking chemicals and dissolved wood material is called black liquor. This substance is recovered and burned in a recovery boiler to produce energy that keeps the process running. In causticising, the cooking chemicals are processed for re-use.
3. Drying and baling
Washed and bleached pulp resembles fluffy white cotton balls.
The pulp is then dried, cut into sheets and baled for easier handling, warehousing and transportation. A standard export unit of pulp consists of eight 250-kilogramme bales.
Now our pulp is ready to travel the world.
Tour our pulp mill
Want to have a closer look at how pulp is made? Take a step by step tour of our pulp mill website and meet our pulp professionals.