Chapter 6 Electric Boilers

Question 1

An immersion-type electric boiler has

a) electrodes
b) no steam space
c) elements
d) tube bundles

Answer 1

c) elements

Question 2

The load on an electrode-type electric boiler is maintained by the

a) amount of steam space in the boiler
b) amount the electrode is covered by water
c) outdoor temperature
d) amount of current flowing through the elements

Answer 2

b) amount the electrode is covered by water

Question 3

Output of an immersion electric boiler is regulated by altering the

a) water level relative to the electrodes
b) water level relative to the elements
c) amount of current flowing through the water
d) amount of current flowing through the elements

Answer 3

d) amount of current flowing through the elements

Question 4

A main disadvantage of an electric boiler is the

a) high cost of manufacturing
b) high cost of the electricity
c) inefficiency of the energy transfer
d) space requirement per unit output

Answer 4

b) high cost of the electricity

Question 5

Electric boilers:

a) require tall stacks for pollution dispersement
b) tend not to be very compact
c) require sootblowers when the fuel is coal
d) have energy conversion efficiencies close to 100%

Answer 5

d) have energy conversion efficiencies close to 100%

Question 6

A salinity feeder is an important component of a/an _________ boiler.

a) vertical tubeless
b) electrode-type electric
c) vertical firetube
d) immersion electric

Answer 6

b) electrode-type electric