GENERAL TRAINING READING PRACTICE TEST 8

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SECTION 3 Questions 27 - 40

Questions 27 - 34


Read the following passage and answer Questions 27 - 40.


PRODUCING SUGAR

Sugar has been known to man for at least 3000 years. There are different types of sugar but the one that most of us recognise is derived from two plants. Although 70% of production comes from the sugar cane which enjoys a tropical climate, the remaining 30% comes from the sugar beet which grows best in more temperate areas.
The production of sugar from sugar beet begins with the sowing of the beet in the spring. In the early years of the industry the seed was sown by hand into pre-made and fertilized drills. By the 1990s however, with the aid of new multi-purpose machinery, the labour intensive methods of the past have been totally eliminated. In addition, a new beet seed has been developed which requires no thinning and which is sown encased in a pellet of fertiliser which not only protects it from pests but also assists and nourishes it through its early development stages.
The harvesting of the sugar beet, or the "campaign" as it is known, starts around the end of September and continues until mid-January. Once the campaign starts, it continues 24 hours a day, seven days a week, until all the beet is processed. Today's mechanical harvester is particularly ingenious. It not only takes the root out of the ground, it also cleans it and cuts off the top of the plants. The leaves are a valuable source of animal feed equal in value per acre to one acre of turnips. The beet is taken by lorry from the harvested field to sugar processing factories. Once inside the factory grounds the lorries drive over a weighbridge where their gross weight is automatically weighed. At the same time a sample of the particular load is taken to determine the sugar percentage and the amount of tare in the overall load. Tare may consist of clay, stones and beet tops. It is deducted from the gross weight of the load in order to determine the net weight of clean beet delivered. The farmer is paid a predetermined price per tonne of clean beet delivered based on a sliding scale related to sugar content. After that the beet is thoroughly washed before processing to remove all traces of clay, stones, grass and sand.
The actual sugar is inside the beet and has to be extracted by a diffusion process. To do this the beet is first cut up into elongated slices. Sugar is then extracted from the beet by diffusing it out with hot water. Beet slices are fed into a large vessel and mixed with the water. A solution of sugar emerges from one end and the exhausted beet slices emerge from the other. The exhausted beet slices, or pulp, are mixed with molasses then dried and sold as animal feed. The solution now left to continue for the rest of the process is referred to as the raw juice and contains about 14% sugar.
At the diffusion stage other substances are extracted from the beet as well as the sugar. So before sugar can be produced in a white crystalline form it is necessary to remove as many of these non-sugars as possible. This part of the process is referred to as juice purification. The main raw materials used in the purification are lime and carbon dioxide gas which are got by burning limestone in a kiln. These substances are added to the juice causing the non-sugars to be precipitated out of the solution as solids. This is then filtered off and discarded.
The purified juice is a sugar solution containing approximately 14% sugar and 1% non-sugars which are left in the liquid. It is now necessary to concentrate this solution. This is done by boiling off water from the solution in large vessels known as evaporators. On leaving the evaporators it contains approximately 60% sugar.
In order to turn the sugar into a crystalline form it is now necessary to evaporate still more water. This is done at a reduced temperature and at high pressure in vacuum pans. Syrup is fed to the pans and, as the water is evaporated off, the crystals of sugar begin to grow. When the pan is full, it contains about 50 tonnes of a mixture of sugar crystals in syrup. The contents are then discharged into large holding vessels known as crystallizers.
The next step in the operation is to separate the sugar from the syrup. This is done in automatically controlled machines known as centrifugals. In them the syrup is spun off and the sugar crystals remain. The wet sugar is then dried, screened, cooled and sent to large bulk storage silos. The syrup from the centrifugals still contains a lot of dissolved sugar. This syrup is put back through two more boiling stages in order to extract still more sugar. The final syrup from which it is no longer practical or economical to extract more sugar is known as molasses. It contains some sugar together with non-sugars which were not removed at the juice purification stage. It is mainly used for animal feed. The total time from beet washing to white sugar is about twelve hours. Depending upon the sugar content of the beet, 100 tonnes of beet will give approximately 12-14 tonnes of sugar and 3 to 4 tonnes of molasses.

Do the following statements below (questions 27 - 34) agree with the information in Reading Passage 3, Producing Sugar?

In boxes 27 - 34 on your answer sheet write:

TRUE if the statement is true
FALSE if the statement is false
NOT GIVEN if the information is not given in the passage


27 Sugar beet isn't grown in tropical areas.
28 Today's sugar beet seeds are produced in a small ball containing food for the seed to help it grow.
29 The discarded leaves and tops of the beet are processed and used as fertiliser.
30 The amount of tare calculated to be in the beet delivered to the factories is taken into account when the beet farmers are paid.
31 The beets are sorted by hand before the processing to remove rotten or inferior beets.
32 The exhausted beet is combined with another by-product of the sugar production process before being sold as animal food.
33 The solid purification by-product is reprocessed to obtain more sugar solution.
34 The purified juice still contains 1% non sugars which are removed before further processing.

Questions 35 - 40

Using the information in the passage, complete the flow chart below. Write your answers in boxes 35 - 40 on your answer sheet.

Use NO MORE THAN THREE WORDS from the passage for each answer.

papertest_8_5_2.jpg

35
36
37
38
39
40


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