Process Technology Equipment Chapter 12 Cooling Towers
5. What are installed on the outer sides of the cooling tower to adjust the
quantity and direction of the airflow into the tower?
A. Fill
B. Louvers
C. Drift eliminators
D. Water distribution header
6. Where are chemicals injected into the cooling water to reduce bacterial growth
and adjust water chemistry?
A. Basin
B. Makeup water
C. Drift eliminators
D. Water distribution header
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9. A cooling tower circulates 40,000 gpm water. The hot water entering the top of
the tower is 115 degrees F and is cooled to 85 degrees F by the time it enters
the cooling tower basin. Assume drift loss is 0.30% of circulation rate,
evaporative losses are 1% for each 10-degree F water temperature decrease,
and blowdown rate is 0.35% of circulation rate. What is the required makeup
in GPM?
A. 1005 gpm
B. 1200 gpm
C. 1425 gpm
D. 1460 gpm
10. What is the temperature at which air is completely saturated with moisture?
A. Humidity
B. Dew point
C. Approach
Process Technology Equipment Chapter 12 Cooling Towers
D. Relative humidity
11. What refers to the cooling tower’s ability to evaporate and cool water?
A. Humidity
B. Dew point
C. Approach
D. Relative humidity
12. Which of the following factors affect the cooling tower performance?
A. Humidity
B. Wind speed
C. Wind direction
D. All of the above
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15. Which of the following may cause exposure to harmful microorganisms?
A. Circulating cooling water through a heat exchanger with ruptured tubes
B. Improper cooling tower lineup
C. Failure to treat cooling water chemically
D. Improper chemical addition to the cooling tower
16. Which of the following may cause reduced production?
A. Improper cooling tower lineup
B. Failure to treat cooling water chemically
C. Improper chemical addition to the cooling tower
D. Circulating cooling water through a heat exchanger with ruptured tubes
17. What might be done to prevent a fire in an older cooling tower made of wood?
A. Install fire extinguishers often.
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B. Install additional fans.
C. Avoid using heat exchangers.
D. Place regular water hoses with lawn sprinklers on top of the towers.
18. What controls biological growth in the tower and in circulating water?
A. pH
B. Biocides
C. Dispersants
D. Corrosion inhibitors
19. What are used to clean the cooling tower and other equipment by keeping
foreign material distributed in the water until filters can remove them?
A. pH
B. Biocides
C. Dispersants
Process Technology Equipment Chapter 12 Cooling Towers
D. Corrosion inhibitors
20. What sounds are associated with improperly lubricated fan bearings?
A. Whirling sounds
B. Swishing sounds
C. Grinding sounds
D. High-pitched sounds
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1. What type of cooling towers are most frequently seen in nuclear and coal-fired
power plants?
A. Natural draft
B. Induced draft
C. Forced draft
D. Open draft
2. Where is cooled water collected to be recycled?
A. Drift
B. Basin
C. Makeup water
D. Drift eliminator
3. Sensible heat loss completes ________ percent of the cooling.
A. 10–20
B. 30–40
C. 50–60
D. 80–90
Process Technology Equipment Chapter 12 Cooling Towers
4. What happens to the rate of evaporation if the temperature is cold?
A. It changes the approach.
B. It increases.
C. It decreases.
D. It stays the same.
5. Which of the following can be caused by foaming?
A. Impaired water circulation
B. Loss of suction in pumps
C. Ruined paint on vehicles
D. All of the above
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Process Technology Equipment Chapter 12 Cooling Towers
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APPENDIX, Chapter 12
Table of Contents
Contents
Page
Checking Your Knowledge Answer Key
31
Process Technology Equipment Chapter 12 Cooling Towers
Checking Your Knowledge Answer Key
1. Define the following terms:
a. Dew point
b. Basin
c. Biocides
d. Blowdown
e. Cooling towers
f. Drift eliminators
g. Evaporation
h. Fill
i. Forced draft cooling towers
j. Induced draft cooling towers
k. Natural draft cooling towers
l. Relative humidity
m. Wet bulb temperature
n. Dry bulb temperature
o. Circulation rate
p. Louvers
q. Counterflow
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2. (True or False) Cooling towers are designed to raise the temperature of a
water stream.
3. (True/False) Natural draft towers have fans or blowers at the bottom of the
tower that force air through the equipment.
4. _____________ are movable plates that adjust the quantity and direction of the
airflow into the tower.
a. Spray nozzles
b. Fans
Process Technology Equipment Chapter 12 Cooling Towers
c. Louvers
d. Basins
5. Drift is water carried over with ________, from the tower.
a. air
b. heat transfer
c. entrainment
d. evaporation
6. The ___________ and temperature of the air determine the amount of heat
removed in a standard amount of air.
a. steam
b. heat transfer
c. entrainment
d. relative humidity
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12. (True/False) Legionnaires’ disease bacteria (LDB), which can exist in cooling
towers, causes a form of pneumonia.