Chapters 7-9

Question 1

What or where is the heat source generally on a thermosyphon reboiler?

Answer 1

Shell side

Question 2

Disadvantages of plate and frame exchangers:

Answer 2

Gaskets easily damaged

High-pressure and high-temperature limitations

Question 3

What methods of heat transfer do heat exchangers use?

Answer 3

Convection and Conduction

Question 4

What is the most commonly used heat exchanger in industry?

Answer 4

Shell and Tube

Question 5

In a cooling tower, what percentage of heat is lost through evaporation?

Answer 5

80-90%

Question 6

List 5 factors that affect efficiency of a cooling tower.

Answer 6

Evaporation
Tower Design
Water Contamination
Equipment Problems
Relative Humidity

Question 7

What is the measurement of how much water the air has absorbed at a given temperature?

Answer 7

Relative Humidity

Question 8

On what does the rate of airflow in a natural-draft cooling tower depend?

Answer 8

Wind Velocity

Question 9

Which tower gets higher airflow: counterflow or crossflow?

Answer 9

Crossflow

Question 10

Which tower is more efficient: counterflow or crossflow

Answer 10

Counterflow

Question 11

List four objectives of water treatment in a cooling tower.

Answer 11

Control algae
Corrosion
Wood Decay
Suspend solids precipitated out of the basin

Question 12

What is blowdown used for in a cooling tower?

Answer 12

Control level of suspended solids in the water basin.

Question 13

List 5 types of heat exchangers

Answer 13

Shell and Tube
Reboiler
Plate and Frame
Air-cooled
Spiral

Question 14

What is the name of the section in a water-tube boiler that pre-heats the water?

Answer 14

Economizer

Question 15

What is a gas-filled section in a boiler-fuel gas burner?

Answer 15

Spud

Question 16

What are the key components of a water-tube boiler?

Answer 16

Furnace
Tubes
Drums
Gas/oil burners
Economizer

Question 17

List 5 operations where steam is used.

Answer 17

Steam turbine
Distillation system
Reaction system
Extrusion
Flare system

Question 18

List the key components of a natural gas burner.

Answer 18

Dampers
Spuds
Impeller
Ignitor

Question 19

List 3 operating problems found in a boiler.

Answer 19

Burns
Instrument Failures
Opening and binding

Question 20

What is the purpose of a steam trap?

Answer 20

To remove condensate from steam lines

Question 21

Name two classes of steam traps.

Answer 21

Mechanical and Thermostatic

Question 22

Name two types of mechanical steam traps.

Answer 22

Inverted Bucket

Float

Question 23

Name a type of thermostatic steam trap.

Answer 23

Bellows-type

Question 24

What term is used for a condition in which slugs of water cause damage to equipment?

Answer 24

Water Hammer

Question 25

Slats that disperse water into small droplets into a small film A. Basin B. Louvers C. Fill D. Wet Deck

Answer 25

C. Fill

Question 26

Majority cooling in cooling tower takes place due to:

Answer 26

Evaporative Cooling

Question 27

``` If outside ambient temperature is 87*, the wet bulb temperature will be: A. Greater than 87 B. Less than or equal to 87 C. The heat index D. Always same as dry bulb ```

Answer 27

B. Less than or equal to 87

Question 28

Difference between temperature of water leaving tower and wet bulb temperature entering tower:

Answer 28

approach to tower

Question 29

``` Cooled water collected in cooling tower: A. fill B. louver C. wet deck D. basin ```

Answer 29

D. basin

Question 30

``` Our tabletop cooling tower is: A. atmospheric B. natural draft C. forced draft D. induced draft ```

Answer 30

D. induced draft

Question 31

Most common type of cooling tower in southeast Texas

Answer 31

Induced Draft

Question 32

Suspended or dissolved solids removed from cooling towers by process called: A. Blowdown B. Absorption C. Adsorption

Answer 32

A. Blowdown

Question 33

``` pH of 7.8 is A. natural B. acidic C. slightly basic D. strong acid ```

Answer 33

C. slightly basic

Question 34

Where does most evaporation occur in cooling tower? A. Fill B. Plenum C. Fan

Answer 34

B. Plenum