11. Read the text gain and answer the questions given.

    1. Why is crude oil desalting necessary as the first step in the series of refinery processes?

    2. Describe the chemical desalting method.

    3. What lies in the base of electrical desalting?

    4. How is desalting method performed? Describe its general steps.

    5. What happens to wastewater and desalted crude oil further?

    6. What fire potential may exist?

    7. When can fouling occur and what harm can it cause?

    8. What can cause corrosion and what are its potential hazards?

    9. When exposure to crude oil, hydrogen sulfide and ammonia may happen?

    10. How can exposures to chemicals and other hazards be prevented?

    11. What substances will wastewater contain?

    12. Describe the method of desalting with the use of diatomaceous earth.

12. State whether the statements are true or false. Prove your point of view.

    1. The two methods of crude oil desalting are chemical and electrostatic separation.

    2. Electrical desalting applies electrostatic charges to dissolve suspended globules.

    3. When large amounts of suspended solids are present in the bottom of the settling tank, surfactants are added.

    4. The temperature of heated crude oil feedstock is limited for better mixing and separation of water.

    5. Ammonia, caustic or acid may be used in both methods of desalting.

    6. The desalted crude is collected from the bottom of the settling tank to the treatment facility.

    7. Equipment failure is caused by fouling and corrosion.

    8. There is a potential for exposure to crude oil until a leak or release occur.

13. Find the sentences with the Participle I / II having attributive function.

1) Having investigated the effect of temperature the authors named came to a definite conclusion. 2) The powder resulting showed no tendency to turn back into metal. 3) The orange-red flame travelled down the tube, flattened into the disk shape and continued to burn. 4) When separating a substance from a mixture you must provide for possible mistakes regarding the purity of the substance. 5) It is the information needed to determine the number of stages. 6) The temperature to which the oil is cooled before adding the acid depends upon the oil being sulphonated. 7) The observation showed the reaction to be inter-molecular and a new substance resulted as an intermediate. 8) The rate of flow of the chemical vapour burned in the experiment was cut down. 9) The substance being investigated contained some impurities. 10) The amount of raw materials and energy entered balance the materials and the energy leaving the process.

14. Translate the following sentences paying attention the Participle II.

1) The employed technique uses a single probe. 2) The rate of a reaction depends on the specific nature of the involved substance. 3) The complexity of the technique involved increased considerably. 4) The state of the liquid obtained remained constant.

15. Translate the sentences defining the forms and functions (adverbial modifiers of time, reason) of the Participle I. Keep in mind that it can be rendered in Russian by: adverbial participle clauses (деепричастные обороты), verbal noun phrases with preposition при and by subordinate clauses with conjunctions когда, пока, в то время как, так как, etc.

1) Water is the most efficient agent, having a high heat transfer coefficient and a high heat capacity. 2) Being taken in proper proportion hydrogen and oxygen combine forming water. 3) Having added an alkaline solution, we got a dark precipitate at the bottom of the vessel. 4) Having been arranged by Mendeleyev in the table, the elements showed their periodic dependence upon the atomic weights. 5) Knowing the volume, the pressure and the temperature of the gas, we can determine the state of its mass. 6) Having been evaporated, the solution of the mother liquid of calcium chloride gave white precipitate (осадок). 7) The heat lowers the surface tension of the oil, allowing water particles to coagulate easier. 8) The desalted crude leaving the dehydrating tank passes through heat exchangers and coolers into storage tanks.

16. Translate the following sentences and phrases comparing the use of the participle forms of the verbs follow (следовать за, придерживаться, наблюдать, следить) attack (воздействовать), influence, affect (влиять, затрагивать), refer to (ссылаться, относить, упоминать, называть).

1) The substance influenced by light changed its colour. 2) Zinc attacked by HCl dissolves. 3) The movement followed through the microscope was zigzag. 4) Precipitation followed by titration gives... 5) Additionally, the H₂S attacking the ozone layer causes further stress on other species. 6) The figures previously referred to are... 7) Substances attacked by moisture should be kept dry. 8) All affected workers must be instructed in appropriate safe work procedures. 9) The operator must report defects and conditions affecting the safe operation of the equipment to the supervisor or employer. 10) The catalyst and the gas form a system that behaves like liquid, i.e. it can flow from one vessel to another being influenced by hydrostatic pressure. 11) The activity of the catalyst can be periodically regenerated by high temperature oxidation of the coke followed by chlorination. 12) For a given crude type and vessel size, factors affecting desalter efficiency include mixing efficiency, inlet header design and location, electrostatic field type and intensity, and electrode design and configuration.