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How does a tree get turned into paper?
Question Date: 2013-05-28
Answer 1:

To go from tree to paper, a tree log must first be "debarked," i.e. have its bark removed. After this, the log is cut into boards of various sizes. These will be used for construction and other industrial needs. The left-over wood is converted into wood chips. These wood chips are then turned into pulp either through mechanical pulping (using steam) or chemical pulping, which separates lignin from cellulose. In the cell walls of wooded plants, cellulose is embedded in a matrix of lignin. Lignin is separated from cellulose because lignin deteriorates over time, which is not a desirable quality in paper. According to Wikipedia, paper that does not contain lignin is called "wood-free paper," which is different from "tree-free paper."


Answer 2:

The process of converting trees into paper consists of several stages: debarking, chipping, pulping, bleaching, paper machine, blade coater, supercalendar, and sheet converting.

First the bark from trees must be removed before the wood can be used, then the logs are cut into small pieces or chips. The wood gets mashed into pulp; in pulping the wood chips are cooked in sodium hydroxide and sodium sulfide to produce a strong dark brown pulp. To purify and clean the pulp, the process uses bleach.

Then comes the process of supercalendar, in which a machine makes the paper glossy and smooth. And finally we have the sheet converting, which is the last stage of paper making.



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