HOW PAPER IS MADE
South Africa is ranked the 15th largest producer of pulp in the world and 24th in paper production.
There are three main stages in paper production, from when the timber arrives at the mill as a raw material right up to the stage when it becomes the final packaged product.
The main source of wood fibre used in the manufacture of paper is harvested from scientifically grown plantations of either hard, (gum), or softwoods, (pine) for conversion into a number of varying grades of paper.
No indigenous trees are used and the siting and planning of plantations takes cognisance of the fact that they need to co-exist with the indigenous environment with minimum impact.
Fibre for papermaking is also sourced from sawmills in the form of wood chips from off-cuts as well as from the recovery of used paper of all types. This “recycled fibre” ensures that the cellulose content, carbon, remains in a form that postpones degradation, (and hence carbon dioxide generation), for as long as possible.
In addition to fibre, a number of chemicals are used to convert the raw cellulose into a form that can be converted into the plethora of paper grades required by the end user:
Other materials used in the paper making process are listed below:
- Pulping chemicals consisting of sodium hydroxide, sodium sulphate, sodium carbonate and calcium oxide are the main constituents. The bulk of these chemicals are recovered in the recovery section of the pulp mill and re-used in the process.
- Water – the bulk of the water is used in the paper making process to dilute cellulose fibre to be formed on the paper machine. Virtually all this water is recovered and recycled back to the machine
Paper making chemicals – such as starches, dyes, and strengthening and water proofing agents – impart a number of different and important properties to the sheet of paper being formed on the machine.