We found out that plants have a lot of use and people use them for quite a lot of purposes.
So plants:
* provide food
* clean the air and provide oxygen
* cool the streets and the city
* save water
* help to prevent water pollution
* heal
* mark the seasons
* create economic opportunities
Nowadays we can't imagine our life without books or products made of paper.
Would you believe paper is made from trees? It’s true! Let’s take a look at how trees are turned into all sorts of paper.
If you look at a tree, you might have a
hard time imagining how something so tall and strong could be turned into something
as thin and weak as a sheet of paper. The process begins with the raw wood,
which is made up of fibers called "cellulose".
To make paper from trees, the raw wood
must first be turned into "pulp". Wood pulp is
a watery “soup” of cellulose wood
fibers, lignin, water and the chemicals used during the pulping process.
Once the pulp is ready, it is then used to make paper
in a process that is quite similar (in the basics) to the process first used by
the ancient Chinese more than 1,900 years ago. Because the pulp mixture is so watery (sometimes as much
as 99 percent water!), the cellulose fibers
need to be separated from the watery mixture.
So plants:
* provide food* clean the air and provide oxygen
* cool the streets and the city
* save water
* help to prevent water pollution
* heal
* mark the seasons
* create economic opportunities
Nowadays we can't imagine our life without books or products made of paper.
Would you believe paper is made from trees? It’s true! Let’s take a look at how trees are turned into all sorts of paper.
If you look at a tree, you might have a
hard time imagining how something so tall and strong could be turned into something
as thin and weak as a sheet of paper. The process begins with the raw wood,
which is made up of fibers called "cellulose".
The cellulose fibers
are stuck together with a natural glue called "lignin" When the lignin is removed and the cellulose fibers
are separated and reorganized, paper can be made.
It’s also possible to make paper from a
variety of other types of plant fibers, such as cotton, flax, bamboo and hemp.
For example, cotton fibers are often used to make the paper that money is printed on. The overwhelming majority (about 95 percent) of the raw material used
to make paper, though, comes from trees.
To make paper from trees, the raw wood
must first be turned into "pulp". Wood pulp is
a watery “soup” of cellulose wood
fibers, lignin, water and the chemicals used during the pulping process.
Wood can be turned to pulp in
a couple of different ways. Mechanical pulping
involves using machines to grind wood chips into pulp.
The resulting pulp retains
most of its lignin, though. The short fibers created by grinding leads to weak paper most
suitable for newsprint, phone books or
other types of low-strength papers.
The more commonly used method is chemical pulping,
also known as “kraft.” Chemicals are used to separate lignin from
the cellulose fibers,
leaving a pulp mixture
that can make stronger papers.
Depending on what type of paper is
desired, the pulp mixture might need to be bleached to create whiter paper. Papermakers
use a variety of chemicals to bleach pulp to the color they want.
Once the pulp is ready, it is then used to make paper
in a process that is quite similar (in the basics) to the process first used by
the ancient Chinese more than 1,900 years ago. Because the pulp mixture is so watery (sometimes as much
as 99 percent water!), the cellulose fibers
need to be separated from the watery mixture.
Huge machines spray the pulp mixture onto moving mesh screens to make
a layered mat. The mat of pulp then goes through several processes to
remove water and dry it out.
Finally, the mat is run through heated
rollers to squeeze out any remaining water and compress it into one continuous
roll of paper that can be up to 30 feet wide.
When the paper has the desired
thickness, it may be colored or coated with special chemicals to give it a
special texture, extra strength or water resistance. As a last step, the paper
rolls are cut to size and packaged for shipping to other facilities for
additional processing to turn it into all sorts of specialized papers.

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