CHAPTER 15
DISTILLATION SYSTEMS
OBJECTIVES
After studying this chapter, the student will be able to:
▪ Describe the principles of distillation.
▪ Describe the relationship between the boiling point of a hydrocarbon and pressure,
temperature, flow, and level.
▪ Describe the various concepts associated with pressure in a distillation system: vapor
pressure, partial pressure, relative volatility, compressibility, liquid pressure, and
vacuum.
▪ Identify the different equipment systems used to make up a distillation system.
▪ Explain how the methods of heat transfer apply to the distillation process.
CHAPTER 15 REVIEW QUESTIONS
1. What is the section of the column located above the feed tray called? Answer: Rectifying
2. What is the section of the column located directly below the feed tray called? Answer:
3. Describe how the liquid and vapor products on each tray in a distillation column could
run countercurrent to each other. Answer: The lighter components in the liquid vaporize
4. After the level builds up on a tray, it flows over the weir. Where does the liquid go when
5. What kind of energy do molecules in motion have? Answer: Kinetic.
7. What is the bottoms product called on a distillation column? Answer: Residual.
8. What is the term for the temperature at which a liquid changes state to a vapor? Answer:
9. What two components does a distillation column balance? Answer: Material and energy
10. What is the incomplete separation of a chemical in a distillation column called? Answer:
11. What is the condensed column product that is pumped back to the top tray of a distillation
12. What device is designed to maintain the temperature in a column? Answer: Reboiler.
13. Name three types of trays found in a distillation plate column. Answer: Bubble-cap,
14. What is heat that cannot be measured called? Answer: Latent heat.
15. Name two types of distillation columns. Answer: Packed and plate.
16. List four conditions that can affect the temperature in a tower. Answer:
a. pressure changes
17. Name three types of packing used in a distillation column.
a. Berl Saddle
18. Explain how to break a flood on a distillation column. Answer: To break a flood the
19. Compare and contrast dry trays and jet flooding. Answer: Jet flooding occurs when the
vapor velocity is so high that liquid down flow in the tower is restricted. Liquid
20. Define Temperature gradient. Answer: The difference between the bottom and upper