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1. What is Sensible Heat?

Sensible Heat is the energy exchanged by a thermodynamic system that has its sole effect a change of temperature

2. What is Latent Heat?

Latent Heat is the Heat released or absorbed by a chemical substances or a thermodynamic system during a change of

state that occurs without a change in temperature, meaning a phase transition such as the Melting of Ice or the boiling ofwater.

3. What is Vapor Pressure?

Vapor Pressure or Equilibrium Vapor Pressure is the pressure of Vapor in Thermodynamic equilibrium with its

condensed phase in closed system. All liquid have a tendency to evaporate and some solids can sublime into a gaseous

form.

4. What is Boiling Point?

Boiling Point is Temperature at which a substance changes its state form liquid and Vapor (Gas) phase of substances

can exist in equilibrium.

5. What is Sensitive Tray Temperature?

6. What is The Primary Function of Bubble Cap Tray?

The Primary Function is for Separation, Rising vapor with more volatile substances transfers heat to the liquid. Some of

the vapor condenses back into liquid form, adding to the liquid on the tray.

7. If the pressure in distillation column increases. What will be effect on the Reboiler an Condenser duty?

Reboiler load will be higher, so reboiler need more steam for heating due to boiling point of component is high than

earlier.

8. What is effect of having higher reflux in a distillation column?

Temperature distillation will dropped and Level column will increased.

9. What are the Condition of Standard Flow and Normal Flow?

10. What are the advantages and disadvantages of using excess air combustion?

11. What is the Physical meaning of Saturated Steam?

Saturated Steam is the temperature at which steam begins to condense (or water begins to boil) for a given pressure, or

more specifically, the temperature at which a liquid-vapor phase change occurs in water.

12. What is NPSH? What is cavitation?

NPSHis anacronymfor Net Positive Suction Head. In any cross-section of a generichydrauliccircuit, the NPSH

parameter shows the difference between the actual pressure of a liquid in a pipeline and the liquid's vapor pressureat a

given temperature.

Cavitationis the formation ofgas bubbles of a flowing liquid in a region where the pressure of the liquid falls below

its vapor pressure.

13. Why surge occurs, how surge is controlled?

Surges occurwhen the compressor outlet pressure is too high in relation to the flow through the compressor. The flow

can change rapidly when there is a sudden change in the load that the compressor is expected to deliver. If the surge is

not controlled, the compressor can be destroyed.

http://en.wikipedia.org/wiki/Acronymhttp://en.wikipedia.org/wiki/Acronymhttp://en.wikipedia.org/wiki/Acronymhttp://en.wikipedia.org/wiki/Hydraulichttp://en.wikipedia.org/wiki/Hydraulichttp://en.wikipedia.org/wiki/Vapor_pressurehttp://en.wikipedia.org/wiki/Vapor_pressurehttp://en.wikipedia.org/wiki/Gashttp://en.wikipedia.org/wiki/Vapor_pressurehttp://en.wikipedia.org/wiki/Acronymhttp://en.wikipedia.org/wiki/Hydraulichttp://en.wikipedia.org/wiki/Vapor_pressurehttp://en.wikipedia.org/wiki/Gashttp://en.wikipedia.org/wiki/Vapor_pressure

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The typical methods for accomplishing surge control are either a blow-off to atmosphere or recirculation from the

outlet to the inlet of the compressor. The anti-surge control strategy is tightly integrated with the compressor load control

strategy.

14. What is specific heat of substance?

The specfic heat capacity of a substance is the amount of energy required to raise the temperature of 1 kg of that

substance by 1 degrees Celius (or Kelvin). 1 kg of water requires 4200 J of energy to raise its temperature by 1 degreesCelcius.

15. a. 2 NaOH + CO2 Na2CO3 + H2O

b. CH4 + 2O2 ---> CO2 + 2H2O

c. C2H4 + H2 C2H6 The above reaction is an example of (1) addition, (2) substitution, (3)

saponification, (4) esterification.

d. S + O2 ----> SO2

e. C2H4 + Cl2 ----> C2H4Cl2

16. Identify the Hazards of hydrocarbon ?

A hydrocarbon contains only hydrogen atoms and carbon atoms. There are a large number of hydrocarbons, but the

simplest is CH4 (methane). One important thing about hydrocarbons is that they are all flammable. When combined with

oxygen (combustion), a hydrocarbon ALWAYS produces carbon dioxide (CO2) and water (H2O).

If a hydrocarbon burns in a plentiful supply of oxygen it will produce carbon dioxide and water, which is fine. However, if

it does not burn in a plentiful supply of oxygen, it will produce carbon monoxide, which is poisonous to humans. In

addition, the lower hydrocarbons are very highly flammable and can be explosive, and many are toxic and can be

absorbed through the skin or lungs.

17. What is the definition of prime and in which equipment it happens this phenomena in industry?

18. What is the Specific of Gravity?

Specific gravityis the ratio of the density(mass of a unit volume) of a substance to the density (mass of the same unitvolume) of a reference substance.

19. What is the function of strainer and normally where is installed?

The straineris designed for the efficient removal and retention of solid/foreign material from flowing liquids and gases. Itprovides the ultimate in protection to vital process equipment, both in simple and in the very increasing sophistication ofprocess plant systems.

Strainer normally installed in :

pumps and compressors

flow meters

valves and regulator

heat exchangers and refrigerating sets

steam traps

instrumentations and ancillary piping items

20. Did Centrifugal compressor has strainer or not?

http://en.wikipedia.org/wiki/Densityhttp://en.wikipedia.org/wiki/Density

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No. it didnt.

21. What are the important parameters for the operation of distillation column?

Temperature, Pressure, Level, Reflux.

22. Give important steps in starting centrifugal pump for hydrocarbon liquid operating at -100 C?

23. Give starting procedure for a motor driven reciprocating compressor?

24. What is surging in centrifugal compressor?

Surgeis a point when compressor is not add enough energy to overcome system resistance.

25. Define Adsorption? Mention any two process in chemical plant using Adsorption?

Adsorption is the adhesion ofatoms, ions, biomolecules ormolecules of gas, liquid, or dissolved solids to a surface. Thisprocess creates a film of theadsorbate (the molecules or atoms being accumulated) on the surface of the adsorbent.

http://en.wikipedia.org/wiki/Atomhttp://en.wikipedia.org/wiki/Ionhttp://en.wikipedia.org/wiki/Biomoleculehttp://en.wikipedia.org/wiki/Moleculehttp://en.wikipedia.org/wiki/Surface_sciencehttp://en.wikipedia.org/wiki/Atomhttp://en.wikipedia.org/wiki/Ionhttp://en.wikipedia.org/wiki/Biomoleculehttp://en.wikipedia.org/wiki/Moleculehttp://en.wikipedia.org/wiki/Surface_science