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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