ABSA 3B2 - Review Questions With Complete Solutions
523. During the start up of a cogeneration system with a gas
turbine:
a. The gas turbine is normally started up by compressed air:
b. The gas turbine is turned/started by a separate starter motor:
c. The gas turbine will start up automatically as soon as power is
engaged:
d. The diverter valve will divert thermal energy from the HRSG
to start the gas turbine:
e. The auxiliary burner will provide additional thermal energy to
start the gas turbine:
b. The gas turbine is turned/started by a separate starter motor:
524. When starting a cogeneration system with a gas turbine, the
starting motor will disengage from the turbine when the turbine
is at approximately ____ % of its rated speed:
a. 5
b. 10
c. 25
d. 35
e. 55
e. 55
525. When starting a cogeneration system with a gas turbine, the
fuel is admitted to the combustor and ignited at approximately
____% of the rated speed of the turbine:
a. 5
,b. 10
c. 25
d. 55
e. 15
d. 55
526. When running up a Cogeneration system the diverter valve
is opened 100% when________________________:
a. the turbine is at rated load
b. the temperature is rising in the turbine blades
c. the combustion turbine temperature is at maximum
d. the HSSG is pre-warmed and up to temperature
e. the HRSG is producing steam
e. the HRSG is producing steam
What does the production of NOX contribute to?
Select one:
a.Alkaline corrosion
b.Scaling of the boiler tubes
c.High pH level in the boiler water
d.Low pH level in the boiler water
e.Acid rain
e.Acid rain
What is cogeneration?
Select one:
a.The use of two forms of input energy to generate one single
,form of output energy
b.The use of steam for process and power generation purposes
c.The use of waste heat from a steam boiler to heat feedwater
d.The simultaneous production of more than one useful energy
output from a single energy source
d.The simultaneous production of more than one useful energy
output from a single energy source
Combined-cycle cogeneration refers to the production of
electricity from which sources?
Select one:
a.One source using one fuel source
b.Two sources using two fuel sources
c.Two sources using one fuel source
d.One source using two fuel sources
c.Two sources using one fuel source
B2C07Q02 In a combined-cycle plant, duct burners
___________________.
Select one:
a.Are only used when the gas turbine is not in service
b.Get enough oxygen from the gas turbine exhaust
c.Are very inefficient, so they are seldom used
d.Require an additional air supply for stable combustion
b.Get enough oxygen from the gas turbine exhaust
What is the main application of a HRSG?
Select one:
a.To act as an auxiliary burner
, b.To generate steam using the exhaust gas of a gas turbine as a
heat source
c.To generate steam using the exhaust gas of a steam turbine as
a heat source
d.To control the superheater temperature
b.To generate steam using the exhaust gas of a gas turbine as a
heat source
Which of the following cogeneration systems is best explained
by the given description? Fuel is burned, which produces heat
from a process. Waste heat from the process is used to produce
steam in a boiler, and the steam from the boiler powers a steam
turbine that drives an electric generator. The exhaust steam from
the steam turbine may drive another turbine or provide heat to
feedwater heaters.
Select one:
a.Back pressure steam turbine
b.Condensing steam turbine
c.Waste heat cogeneration
d.Heat engine cogeneration
e.Gas turbine
c.Waste heat cogeneration
The benefits of a combined cycle with a single-shaft gas/steam
turbine arrangement include which of the following?
1. High level of thermal efficiency
2. Low capital cost
3. Fast start-up and shutdown
4. Short construction time
523. During the start up of a cogeneration system with a gas
turbine:
a. The gas turbine is normally started up by compressed air:
b. The gas turbine is turned/started by a separate starter motor:
c. The gas turbine will start up automatically as soon as power is
engaged:
d. The diverter valve will divert thermal energy from the HRSG
to start the gas turbine:
e. The auxiliary burner will provide additional thermal energy to
start the gas turbine:
b. The gas turbine is turned/started by a separate starter motor:
524. When starting a cogeneration system with a gas turbine, the
starting motor will disengage from the turbine when the turbine
is at approximately ____ % of its rated speed:
a. 5
b. 10
c. 25
d. 35
e. 55
e. 55
525. When starting a cogeneration system with a gas turbine, the
fuel is admitted to the combustor and ignited at approximately
____% of the rated speed of the turbine:
a. 5
,b. 10
c. 25
d. 55
e. 15
d. 55
526. When running up a Cogeneration system the diverter valve
is opened 100% when________________________:
a. the turbine is at rated load
b. the temperature is rising in the turbine blades
c. the combustion turbine temperature is at maximum
d. the HSSG is pre-warmed and up to temperature
e. the HRSG is producing steam
e. the HRSG is producing steam
What does the production of NOX contribute to?
Select one:
a.Alkaline corrosion
b.Scaling of the boiler tubes
c.High pH level in the boiler water
d.Low pH level in the boiler water
e.Acid rain
e.Acid rain
What is cogeneration?
Select one:
a.The use of two forms of input energy to generate one single
,form of output energy
b.The use of steam for process and power generation purposes
c.The use of waste heat from a steam boiler to heat feedwater
d.The simultaneous production of more than one useful energy
output from a single energy source
d.The simultaneous production of more than one useful energy
output from a single energy source
Combined-cycle cogeneration refers to the production of
electricity from which sources?
Select one:
a.One source using one fuel source
b.Two sources using two fuel sources
c.Two sources using one fuel source
d.One source using two fuel sources
c.Two sources using one fuel source
B2C07Q02 In a combined-cycle plant, duct burners
___________________.
Select one:
a.Are only used when the gas turbine is not in service
b.Get enough oxygen from the gas turbine exhaust
c.Are very inefficient, so they are seldom used
d.Require an additional air supply for stable combustion
b.Get enough oxygen from the gas turbine exhaust
What is the main application of a HRSG?
Select one:
a.To act as an auxiliary burner
, b.To generate steam using the exhaust gas of a gas turbine as a
heat source
c.To generate steam using the exhaust gas of a steam turbine as
a heat source
d.To control the superheater temperature
b.To generate steam using the exhaust gas of a gas turbine as a
heat source
Which of the following cogeneration systems is best explained
by the given description? Fuel is burned, which produces heat
from a process. Waste heat from the process is used to produce
steam in a boiler, and the steam from the boiler powers a steam
turbine that drives an electric generator. The exhaust steam from
the steam turbine may drive another turbine or provide heat to
feedwater heaters.
Select one:
a.Back pressure steam turbine
b.Condensing steam turbine
c.Waste heat cogeneration
d.Heat engine cogeneration
e.Gas turbine
c.Waste heat cogeneration
The benefits of a combined cycle with a single-shaft gas/steam
turbine arrangement include which of the following?
1. High level of thermal efficiency
2. Low capital cost
3. Fast start-up and shutdown
4. Short construction time
