Stock of firewood fragments
Pinus and eucalyptus wood are the most commonly used raw materials for papermaking.
After cutting, the logs are peeled, giving rise to the chips that generate the cellulose and are used as fuel to produce steam and electricity.
The conversion of wood into pulp consists of the separation of cellulosic fibers by the removal of lignin, a kind of glue that binds these fibers.
The mechanical thermo-chemical pulp is the pulp obtained by the pressing of the trunks in the presence of water.
Firewood fragments, mixed with chemicals, are cooked under high pressure. The action dissolves the lignin and separates the fibers. Papers made of chemical pulp are very resistant, as is the case of the Kraft, Germanic word of origin that designates force.
Process by Recycling
Disintegration of shavings in water and removal of contaminants such as plastic, metal and polyethylene.
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The manufacture of some papers requires the bleaching of the pulp. For this, chemical products are used that eliminate lignin. The pulp resulting from this process is whiter and has a lower tendency to yellow over time.
New technologies have considerably reduced the environmental impact of the bleaching process.
The pulp reaches the inbox of the paper machine containing more than 99% water. The mixture is poured in the form of a fine, uniform jet over the forming screen. The filtering action of the screen, combined with a vacuum system, extracts much of the water contained in the pulp, thereby forming the sheet of paper. The sheet is pressed between rollers to remove more water. It then goes through the drying section, where it comes in contact with drying cylinders that extract the remaining water through evaporation.
The finishing consists in the conversion into cut sheets and packaging of all products. The process uses modern equipment for cutting, packaging and palletizing. Currently, in most factories all production is performed automatically, without manual contact.