particularly in the Baltic Sea where old pulp
brown colour. The pulping stage separates the
mills had discharged untreated effluents for
wood into fibres so they are suitable for paper
100 years, have disturbed the international
making. Pulping can be done by mechanical
community.
grinding, or by chemical treatment in which
woodchips are 'cooked' with chemicals, or by a
3. Until the 1950s, it was common for pulp
combination of both methods.
mills and other industries to discharge
untreated effluent into rivers and seas. The
6. Kraft pulping is the most widely used
environmental effects were at the time either
chemical process for producing pulp with the
not understood, or regarded as an acceptable
strength required by the high-quality paper
cost of economic prosperity in an increasingly
market. It is now usually carried out in a
import-oriented world economy. But greater
continuous process in a large vessel called a
environmental awareness has spurred a
digester. Woodchips are fed from a pile into the
fundamental change in attitude in the
top of the digester. In the digester, the chips are
community, in government and in industry itself.
cooked in a solution called white liquor,
osed of caustic soda (sodium hydroxide)
involving a furnace and tanks, some of the
and sodium sulphide. The chips are cooked at
black liquor is transformed into energy, while
high temperatures of up to 170° C for up to
some is regenerated into the original white
three hours. The pulp is then washed and
cooking liquor. The recovery system is an
eparated from the spent cooking liquor which
integral part of production in the pulp and
has turned dark and is now appropriately
paper industry. The pulp that comes out has
called black liquor. An important feature of
little lignin left in the fibres. Bleaching removes
kraft pulping is a chemical recovery system
the last remain-ing lignin and brightens the
which recycles about 95% of the cooking
pulp. Most modern mills have modified their
chemicals and produces more than enough
pulping processes to remove as much of the
lignin as possible before the pulp moves to the
energy to the mill. In a series of steps
bleaching stage.
Questions 29-32
Below is a list of possible factors, A-G, which will influence the amount of paper
being used in the future. From the list, choose FOUR factors which are mentioned
in Paragraph 1 of the reading passage. Write your answers A-G, in the spaces
numbered 29-32 on the answer sheet.
List of factors
A more people read newspapers
B increased use of paper bags
C
increased book production for education
D
wider use of sign post advertising
E
increased use of fax machines
F
wider use of leaflet advertising
G
greater use of duplicating machines
Questions 33-35
The following THREE statements are summaries of Paragraphs 2, 3 and 4
respectively. However, they are incomplete. Complete each of the statements using
NO MORE THAN THREE WORDS FROM THE TEXT. Write your answers in
the spaces numbered 33-35 on the answer sheet.
33. The international community has begun to demand ...
34. In the past, the environmental effects of pulp mill practices, were probably a
price to pay for...
35. Some paper mills have recently modernised their mill design in order to
decrease...
Questions 36-40
Below is a list of possible steps in the kraft process of turning wood chips into
paper. They are numbered 1-8. Only FIVE of the steps listed below are mentioned
in the passage. The steps are not listed in the correct order. Decide which steps are
mentioned and write them in the correct order. Write the appropriate number for
each step in the correct order in the spaces numbered 36-40 on the answer sheet.
1
the chips are cooked
2
the fibres are bound by lignin
3
the pulp is bleached
4
woodchips are put into a pile
5
the pulp is dried
6
the pulp is removed from the black liquor
7
the chips are put into the white liquor
8
the pulp is washed
READING TEST 2
QUESTIONS 1-14
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