how paper is made
Step 1: Forestry
Typically, trees used for papermaking are specifically grown and harvested like a crop for that purpose. To meet tomorrow's demand, forest products companies private landowners in Wisconsin plant millions of new seedlings every year.
Step 2: Debarking and Chipping
To begin the process, logs are passed through a debarker, where the bark is removed, and through chippers, where spinning blades cut the wood into 1" pieces. Those wood chips are then pressure-cooked with a mixture of water and chemicals in a digester.
Step 3: Pulp Preparation
The pulp is washed, refined, cleaned, and sometimes bleached, then turned to slush in the beater. Color dyes, coatings and other additives are mixed in, and the pulp slush is pumped onto a moving wire screen.
Step 4: Paper Formation
As the pulp travels down the screen, water is drained away and recycled. The resulting crude paper sheet, or web, is squeezed between two large rollers to remove most of the remaining water and ensure smoothness and uniform thickness. The semi-dry web is then run through heated dryer rollers to remove the remaining water.
Step 5: Paper Finishing
The finished paper is then rolled into large rolls, which can be 30 feet wide and weigh close to 25 tons. A slitter cuts the paper into smaller, more manageable rolls, and the paper is ready for use.