1. Drier - сушилка

2. to precede - предшествовать

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характер обработки

3.

4. 5. б. 7.

handling characteristics

to reveal - обнаруживать

tube - труба, трубка

jacket - стенка цилиндра

friction - трение

to design - ЗД.: предназначаться

batch operation - периодическое действие

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11

12

13

14

15

16,

17,

18,

19,

20,

wallboard - стеновая плита

combustion - сгорание

contamination - загрязнение

revolving drum - вращающийся барабан

by the effect of - под воздействием

scoops = blade - лопасть, лопатка

baffle - перегородка, турбулизатор потока

dam - запруда, перемычка

ring - кольцо, обруч, ободок

to retard - замедлять

residence time - время (длительность) пребывания

Answer the following questions:

1. What does drying generally signify?

2. What are the two most useful classifications'of driers based on?

3. What driers do you know according to the first method of classification?

4. What is a direct (indirect, mechanical) drier?

5. What does the second method of classification of driers consider?

6. What do direct driers use as the heating medium?

7. What does a rotary drier consist of?

8. How do solids move on through a rotary drier?

9. For what purpose are baffles and dam rings used?

10. How may the length of the cylinder vary?

Exercises

I. Translate the following sentences paying attention to the meaning of the word "time" :

1. There was- a time when people knew nothing about polymers.

2. One of the cylinders is four times as large as the other one,

3. In those times lightning was a subject for legends.

4. At times he comes to visit us.

5. Three times four .is twelve.

6. What time is it? I think it is time to stop the motor.

7. We cannot test this drier at a time.

II. -Translate the following sentences. Mind the Absolute Par-, ticiple Construction:

1. D.I.Mendeleyev being a great chemist, his name is well known not only in the USSR but also abroad.

2. Hydrogen is the simplest substance, atoms of other elements having a more complex structure.

3. The properties of the element having been discovered, it was much easier to use it.

4. Moscow and London have different climate, the average temperature being higher in London than in Moscow.

5. Our students studying chemistry, many experiments are made at the laboratory.

6. The settlement occupies a large area, the houses being built along the river.

7. Radioactivity having been discovered, science made great progress in atomic physics.

8. London is divided by the river Thames into two parts, the East-End being inhabited by the working people of the city.

III. Ask questions on all the parts of the following sentences 8

1. Some new driers were developed in the USSR last year.

.2. They carry on their research work in the laboratory of ana-

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lytlcal chemistry.

IV. Translate the following text using a dictionary!

Evaporators

Evaporation is the removal of solvent as vapour from a solution or slurry. The vapour may or may not be recovered depending on its.value. The end product may be a solid, but the transfer of heat in the evaporator must be to a solution or a suspension of the solid in liquid. Evaporators are similar to reboilers of distillation columns except that no attempt is made to separate components of the vapour.

There are three principal elements involved in evaporator design - heat transfer, vapour-liquid separation, and energy utilization. The units in which heat transfer takes place are called heating elements or calandrias.

Heat transfer is the most important factor in evaporator design since the heating surface represents the largest part of evaporator cost.

There are many types of evaporators used in industry. The largest user of evaporation equipment is the pulp and paper industry. This industry produces the largest quantity of evaporators.