Chapter 7 steam Flashcards
4 wrong
What term is used to describe the energy added in the phase change from a liquid to steam?
Kinetic heat
latent heat
answer B
Which of the following steam pressures would be labeled ultrahigh-pressure steam?
100 psig
15000 psig
answer B
What demineralizes water by replacing positively charged calcium and magnesium ions with other cations (hydrogen ions) that do not cause scale?
An infuser
A cation exchanger
answer B
Which type of ion has a positive charge?
Cation
Anion
answer A
Ions like Cl- or SO4– would be adsorbed (stuck) onto the surface of a cation bed.
True
False
answer B
To regenerate a Cation bed, which would be used?
Strong chloride
Strong acid
answer B
If you flow a solution of Na+ Cl- in water over an Anion resin, what will be in the outlet stream leaving the bed?
Na+ and OH- and water
Na+ and Cl- and water
answer B
If you flow a solution of Mg++ CO3– in water over a Cation resin, what will be in the outlet stream leaving the bed?
H+ and CO3– and water
pure water
answer A
In a water tube boiler, the water is inside the tubes.
True
False
answer A
The steam drum usually runs about 50% full of liquid.
True
False
answer A
The mud drum usually runs about 50% full of liquid.
True
False
answer B
The condensate is circulated between the mud drum and the steam drum by a condensate pump.
True
False
answer B
How are tubed economizer sections sometimes used to heat boiler feedwater further after deaeration?
By using dedicated gas burners
By using furnace flue gas waste heat
answer B
What is a characteristic of the water (condensate) recovered from steam use throughout the plant?
It is very clean
It is very toxic
answer A
What device may be installed in a pressure-reducing station to cool the temperature when the steam temperature difference between the two steam headers is significant?
A cooling loop
An attemperator / desuperheater
answer B
Steam that is produced from a boiling pool of water will initially be saturated steam.
True
false
answer A
super heated steam is
Steam heated above the dew point at the operation pressure
The result of a sudden reduction of pressure on hot water
answer A
Which type of steam is preferred for heating using heat exchangers?
Saturated steam
superheated steam
answer A
Which type of steam is preferred for transporting steam to other blocks?
Saturated steam
superheated steam
answer B
What is the advantage of returning recovered condensate directly to the boiler feedwater system rather than using cold treated water?
It is more plentiful than cold treated water.
It is more efficient because it requires adding fewer BTUs to turn it to steam.
answer B
What is the function of a steam pressure controller?
To supply additional steam to the system as steam in the header is used
To register any abnormalities in steam pressure
answer A
A stack flue gas analyzer samples flue gases to ensure that the air supply matches the indicated ________ required for optimal boiler operation.
4.25%
0.00%
answer A
What term is used to describe the impact and resulting noise from the energy of water rushing to occupy that space throughout the entire system when a “bubble” of steam collapses suddenly?
a steam hammer
thermal thunder
answer A
In the event of the total loss of combustion air causing furnace fires to be extinguished, what is the course of action to take?
Perform emergency boiler shutdown.
Flush out furnace with nitrogen gas
answer A
In the event of tube failures, which action should be taken?
Perform emergency boiler shutdown
Attempt to replace failed tubes without interrupting boiler operation.
answer A
When do furnaces experience the most hazardous operating conditions, according to statistics?
During electrical storm
When being started up from a “cold” condition
answer B
What process displaces oxygen and other gases to allow vessel entry and hot work (such as torch burning or welding) to be performed?
Steam clearing
steam displacement
answer A
What is the purpose of the deaerator?
Removes CO2 and O2 from boiler feedwater
Cools the feed to the boiler
answer A
The boiler feedwater pumps are usually low pressure, high volume centrifugal pumps.
True
false
answer B
Boiler feedwater pumps must maintain a minimum ________ to prevent damage to the pump’s internal workings.
Discharge flow
retention for priming
answer A
Boiler water too low in pH will cause ___________ in the boiler tubes.
pitting
scale
answer A
Boiler water too high in pH will cause ___________ in the boiler tubes.
Caustic embrittlement
Low temperature
answer A
As the total hardness increases the conductivity will
Increase
Decrease
answer A
Blowdown of a boiler is used to:
Control of level
control of solids
answer B
