POWER ENGINEERING 4TH CLASS A2 CHAPTER 66
QUESTIONS
If boiler feedwater is neutral, its pH is:
a. 0
b. 5
c. 7
d. 9
e. 13 - Answer -c
Pitting of boiler metal may be prevented by:
a. Preheating boiler feed water to between 80 and 105°C
b. Cooling the feeder water to between 4 and 16°C
c. The addition of sodium chloride to the feed water
d. Softening the feed water before it enters the boiler
e. Adding sodium sulphate to the feed water - Answer -a
The dissolved solids in raw water:
a. Cause pitting of boiler surfaces
b. Cause grooving of piping surfaces
c. Are organic matter
d. Cannot be removed with filters
e. Cause corrosion of boiler surfaces - Answer -d
Boiler water with a pH of 6 is considered:
a. Alkaline
b. Basic
c. Acidic
d. Neutral
e. Ideal boiler water - Answer -c
The zeolite inside a water softener is used to:
a. Regenerate the brine solution
b. Rinse the softened water
c. Exchange sodium for calcium and magnesium
d. Exchange soda for calcium and magnesium
e. Exchange calcium for magnesium - Answer -c
A treatment method that is often used in conjunction with settling tanks is:
a. Deaeration
b. Zeolite softening
c. De-mineralizing
d. Lime soda softening
e. Filtration - Answer -e
, A normal operating range for the pressure in a deaerator is ___________ kPa.
a. 70 to 100
b. 30 to 50
c. 100 to 150
d. 10 to 25
e. 5 to 35 - Answer -a
The chemical used to regenerate the anion exchanger of a demineralizer is:
a. Sodium hydroxide
b. Sulphuric acid
c. Sodium chloride
d. Hydrochloric acid
e. Sulphamic acid - Answer -a
Lime-soda softeners:
a. Remove all dissolved solids from the water
b. Must be backwashed periodically
c. Remove all dissolved solids and gases from the water
d. Remove lime from groundwater
e. Remove the scale forming dissolved solids - Answer -e
Boiler water is treated in order to:
a. prevent the water from becoming too soft
b. prevent the water from becoming too alkaline
c. reduce the environmental impact of the blowoff effluent
d. remove suspended matter
e. prevent scale deposition and waterside corrosion - Answer -e
Water filters must be cleaned:
a. If the water becomes hard
b. When the dissolved solids are high
c. By backwashing the filter media
d. By chemically cleaning the filter media
e. Once per shift - Answer -c
Suspended matter must be removed from feedwater to:
a. Prevent overheating of the boiler metal
b. Prevent boiler waterside scale deposits
c. Reduce the alkalinity of the water
d. Eliminate the hardness of the water
e. Prevent boiler corrosion - Answer -a
Temporary hardness in feedwater is caused by:
a. Calcium sulphate
b. Sodium nitrate
QUESTIONS
If boiler feedwater is neutral, its pH is:
a. 0
b. 5
c. 7
d. 9
e. 13 - Answer -c
Pitting of boiler metal may be prevented by:
a. Preheating boiler feed water to between 80 and 105°C
b. Cooling the feeder water to between 4 and 16°C
c. The addition of sodium chloride to the feed water
d. Softening the feed water before it enters the boiler
e. Adding sodium sulphate to the feed water - Answer -a
The dissolved solids in raw water:
a. Cause pitting of boiler surfaces
b. Cause grooving of piping surfaces
c. Are organic matter
d. Cannot be removed with filters
e. Cause corrosion of boiler surfaces - Answer -d
Boiler water with a pH of 6 is considered:
a. Alkaline
b. Basic
c. Acidic
d. Neutral
e. Ideal boiler water - Answer -c
The zeolite inside a water softener is used to:
a. Regenerate the brine solution
b. Rinse the softened water
c. Exchange sodium for calcium and magnesium
d. Exchange soda for calcium and magnesium
e. Exchange calcium for magnesium - Answer -c
A treatment method that is often used in conjunction with settling tanks is:
a. Deaeration
b. Zeolite softening
c. De-mineralizing
d. Lime soda softening
e. Filtration - Answer -e
, A normal operating range for the pressure in a deaerator is ___________ kPa.
a. 70 to 100
b. 30 to 50
c. 100 to 150
d. 10 to 25
e. 5 to 35 - Answer -a
The chemical used to regenerate the anion exchanger of a demineralizer is:
a. Sodium hydroxide
b. Sulphuric acid
c. Sodium chloride
d. Hydrochloric acid
e. Sulphamic acid - Answer -a
Lime-soda softeners:
a. Remove all dissolved solids from the water
b. Must be backwashed periodically
c. Remove all dissolved solids and gases from the water
d. Remove lime from groundwater
e. Remove the scale forming dissolved solids - Answer -e
Boiler water is treated in order to:
a. prevent the water from becoming too soft
b. prevent the water from becoming too alkaline
c. reduce the environmental impact of the blowoff effluent
d. remove suspended matter
e. prevent scale deposition and waterside corrosion - Answer -e
Water filters must be cleaned:
a. If the water becomes hard
b. When the dissolved solids are high
c. By backwashing the filter media
d. By chemically cleaning the filter media
e. Once per shift - Answer -c
Suspended matter must be removed from feedwater to:
a. Prevent overheating of the boiler metal
b. Prevent boiler waterside scale deposits
c. Reduce the alkalinity of the water
d. Eliminate the hardness of the water
e. Prevent boiler corrosion - Answer -a
Temporary hardness in feedwater is caused by:
a. Calcium sulphate
b. Sodium nitrate