Power Engineering MCQ: October 2017

1 Raise steam during startup
2 Sustain a stable ignition while establishing a char bed
3 Stabilize conditions during upsets in the black liquor feed
4 Produce extra steam as required by the process of for power production
5 Burn out the char bed when shutting down
6 Maintain furnace temperatures

A ) 1, 2, 3, 4, 5
B ) 3, 4, 5, 6
C ) 1, 3, 5
D ) 1, 2, 3, 4, 5, 6

Answer: A

There is also corrosion caused by _________ in refuse-fired boilers.

A ) chlorides
B ) fuels
C ) materials
D ) burning

Answer: A

The liquor droplets must be ______ enough to minimize entrainment in the combustion gases.

A ) small
B ) large
C ) dispersed
D ) fine

Answer: B

The primary function of the recovery boiler is to process ______ liquor.

A ) white
B ) green
C ) black
D ) liquor

Answer: C

Fluidized bed boilers have the ability to burn ________ fuels in an environmentally acceptable manner.

A ) low grade
B ) high grade
C ) liquid
D ) vaporized

Answer: A

Outputs from Steam Flooding Boilers range from _ million kJ/h to _ million kJ/h in standard sizes.

A ) 1 , 100
B ) 5 , 50
C ) 100 , 200
D ) 1 , 50

Answer: B

If the black liquor is too ______, it too can result in an explosion.

A ) strong
B ) thin
C ) weak
D ) thick

Answer: C

The reason for the use of steam is to allow the maximum quantity of heat to be put into the well with the ________ quantity of injected fluid.

A ) minimum
B ) maximum
C ) most
D ) super

Answer: A

The main application for ______ boilers is steam generation using gas turbine exhaust gas as a heat source.

A ) fluidized bed
B ) HRSG
C ) Once through
D ) Steam flooding

Answer: B

One method of burning _____ is called fluidized bed combustion.

A ) liquids
B ) wood
C ) methane
D ) coal

Answer: D

These types of boilers (A, D, and O) have furnaces cooled by _________ lining the furnace walls.

A ) water tubes
B ) fans
C ) desuperheaters
D ) air circulation

Answer: A

Where the boiler provides the entire steam supply to an electric generating unit, the output of the boiler is expressed in terms of power output of the generator (for example a 300 megawatt boiler).

A ) True
B ) False

Answer: A

The purpose of the downcomer is to supply:

A ) Hot water to the steam drum
B ) Cool water to the steam drum
C ) Cool water from steam drum to rest of boiler
D ) Steam to steam drum
E ) boiler feed water to the boiler

Answer: C

Natural circulation in a boiler depends upon the ___________ in the density of a column of water and the density of a column containing a steam/water mixture.

A ) amount
B ) similar
C ) difference
D ) mass

Answer: C

There are several factors that influence the natural circulation in a watertube boiler. These are:

A ) The height of the steam drum above the bottom drum or header.
B ) The amount of heat applied to the tube. The hotter the tube becomes, the more steam bubbles are formed, creating more mass differential and thus more circulation.
C ) The operating pressure of the boiler. As boiler pressures increase, the density of the steam increases
D ) The cleanliness of the tubes can also affect circulation.
E ) All of the above

Answer: E

The main advantage of the packaged boiler is its _ _.

A ) small size
B ) compact design
C ) low cost
D ) quality steam

Answer: C

The difference in density between water and saturated steam becomes progressively less with increased pressure and disappears altogether at the critical pressure _______ .

A ) 22106 kPa
B ) 15000 kPa
C ) 10000 kPa
D ) 25000 kPa

Answer: A

Feed-water entering the boiler section first passes through the __________ section where it is heated by the combustion gases leaving the boiler.

A ) furnace
B ) economizer
C ) boiler drum
D ) superheater

Answer: B

Field erected boilers have outputs of?

A ) 75000 kg/h
B ) 100000 kg/h
C ) 100 mg/h
D ) 150000 kg/h or more

Answer: D

The disadvantages of forced circulation in a boiler are the __ _ of equipment, pumps, piping, etc.

A ) greater use
B ) increased costs
C ) higher maintenance
D ) numbers of

Answer: B

One square metre of heating surface equals 10 kilowatts. The heating surface of a boiler must be determined by computing the area of the surface involved in square metres and where a computation is to be made of a curved surface; the surface having the greater radius shall be taken.

A ) True
B ) False

Answer: A

The advantage of forced circulation in a boiler is a _________ flow in all tubes.

A ) negative
B ) greater
C ) positive
D ) mass

Answer: C

The arrangement of a once through boiler has no drums. The feed water is heated and then evaporated and superheated in through the unit.

A ) Two passes
B ) One passage
C ) 3 passes
D ) 4 passes

Answer: B

Generally two types of draft fans are used. A _ fan supplies air to the air preheater. The preheated air (350°C) for combustion goes to the coal pulverizers and to the burners. An __ fan exhausts the combustion gases (170°C) from the air heater to the stack.

A ) center mounted, external mounted
B ) forced draft, induced draft
C ) induced draft, forced draft
D ) turbine draft, ejection draft

Answer: B

Steam generators operating above critical pressure are said to be __-critical and steam generators operating below critical pressure are classed as -critical.

A ) sub , super
B ) super, sub
C ) normal, pre
D ) high, low

Answer: B

Combustion air for the burners is preheated to ______350°C in the air heater section by combustion gases leaving the economizer section.

A ) 150 °C
B ) 100 °C
C ) 350 °C
D ) 500 °C

Answer: C

Packaged watertube boilers capacities range from?

A ) 2300 kg to 65000 kg per hour
B ) 500 kg to 100 mg per hour
C ) 15 psi to 15000 kg per hour
D ) 65000 to 100000 kg per hour

Answer: B

The downcomers are located in the regions of the boiler, or external to the furnace altogether. The risers are located in the __ zones of the boiler, being exposed to radiant heat of the furnace or to the very hot flue gases near the furnace.

A ) back, front
B ) cooler, hottest
C ) water, furnace
D ) drum, radiant

Answer: B

The downcomers are located in the regions of the boiler, or external to the furnace altogether. The risers are located in the __ zones of the boiler, being exposed to radiant heat of the furnace or to the very hot flue gases near the furnace.

A ) back, front
B ) cooler, hottest
C ) water, furnace
D ) drum, radiant

Answer: B

Where electric power is used as the heating source, the boiler rating shall be the maximum kilowatt rating of the .

A ) Power Plant
B ) Heating element
C ) Boiler wiring
D ) MCC

Answer: B

The steam separating equipment separates the _______ from the steam/water mixture.

A ) water
B ) steam
C ) impurities
D ) water droplets

Answer: B

A steam generating unit consists of a number of elements all of which contribute to the production of steam.The elements of a typical steam generator include:

1 boiler
2 superheater
3 water conditioner
4 reheater
5 economizer
6 steam piping
7 air heater
8 fuel equipment
9 draft fans

A ) 1, 2, 7, 8, 9
B ) 1, 2, 4, 5, 7, 8, 9
C ) 3, 4, 6, 7, 8
D ) 1, 2, 3, 4, 5, 6, 7, 8, 9

Answer: D

Heat recovery started to be added to the refuse incinerators, as did strict air pollution guidelines. The basic incinerators with waste heat recovery have evolved into _________ boilers with integral stokers.

Combustion can take place at temperatures ranging from ____°C to ____°C instead of normal combustion temperatures of 1600°C to 1900°C for pulverized coal and oil firing.

Inconel is an alloy composed of _______ and chromium.

Crushed coal from 1.6 mm to 6 mm is injected into the bed by means of an ________.

Systems to burn wood and biomass usually involve a separate ________, called a dutch oven, or a traveling grate or vibrating grate arrangement.

Because of the low operating temperatures, an inexpensive material such as CaCO3 (lime) can be added to the bed. It acts as a sorbent to remove ______ from the flue gases.

Bubbling Fluid Bed Boilers (BFB) are subject to _____ erosion rates.

The pinhole grates have __________ air holes to admit air to the burning material on the grate.

A simple combined cycle power generation system can consist of:

A particular application of the once-through boiler design is the steam-flooding boiler. This is a boiler used for flooding oil wells with steam in order to increase the oil recovery.

List the five functions of the auxiliary fuel burners:

There is also corrosion caused by _________ in refuse-fired boilers.

The liquor droplets must be ______ enough to minimize entrainment in the combustion gases.

The primary function of the recovery boiler is to process ______ liquor.

Fluidized bed boilers have the ability to burn ________ fuels in an environmentally acceptable manner.

Outputs from Steam Flooding Boilers range from ___ million kJ/h to ___ million kJ/h in standard sizes.

If the black liquor is too ______, it too can result in an explosion.

The reason for the use of steam is to allow the maximum quantity of heat to be put into the well with the ________ quantity of injected fluid.

The main application for ______ boilers is steam generation using gas turbine exhaust gas as a heat source.

One method of burning _____ is called fluidized bed combustion.

These types of boilers (A, D, and O) have furnaces cooled by _________ lining the furnace walls.

Where the boiler provides the entire steam supply to an electric generating unit, the output of the boiler is expressed in terms of power output of the generator (for example a 300 megawatt boiler).

The purpose of the downcomer is to supply:

Natural circulation in a boiler depends upon the ___________ in the density of a column of water and the density of a column containing a steam/water mixture.

There are several factors that influence the natural circulation in a watertube boiler. These are:

The main advantage of the packaged boiler is its _____ _____.

The difference in density between water and saturated steam becomes progressively less with increased pressure and disappears altogether at the critical pressure _______ .

Feed-water entering the boiler section first passes through the __________ section where it is heated by the combustion gases leaving the boiler.

Field erected boilers have outputs of?

The disadvantages of forced circulation in a boiler are the ______ _____ of equipment, pumps, piping, etc.

One square metre of heating surface equals 10 kilowatts. The heating surface of a boiler must be determined by computing the area of the surface involved in square metres and where a computation is to be made of a curved surface; the surface having the greater radius shall be taken.

The advantage of forced circulation in a boiler is a _________ flow in all tubes.

The arrangement of a once through boiler has no drums. The feed water is heated and then evaporated and superheated in ______ ______ through the unit.

Generally two types of draft fans are used. A _____ ____ fan supplies air to the air preheater. The preheated air (350°C) for combustion goes to the coal pulverizers and to the burners. An ______ ____ fan exhausts the combustion gases (170°C) from the air heater to the stack.

Steam generators operating above critical pressure are said to be ______-critical and steam generators operating below critical pressure are classed as ____-critical.

Combustion air for the burners is preheated to ______350°C in the air heater section by combustion gases leaving the economizer section.

Packaged watertube boilers capacities range from?

The downcomers are located in the ______ regions of the boiler, or external to the furnace altogether. The risers are located in the ________ zones of the boiler, being exposed to radiant heat of the furnace or to the very hot flue gases near the furnace.

The downcomers are located in the ______ regions of the boiler, or external to the furnace altogether. The risers are located in the ________ zones of the boiler, being exposed to radiant heat of the furnace or to the very hot flue gases near the furnace.

Where electric power is used as the heating source, the boiler rating shall be the maximum kilowatt rating of the ______ ______.

The steam separating equipment separates the _______ from the steam/water mixture.

A steam generating unit consists of a number of elements all of which contribute to the production of steam.The elements of a typical steam generator include:

Combustion can take place at temperatures ranging from °C to °C instead of normal combustion temperatures of 1600°C to 1900°C for pulverized coal and oil firing.

Outputs from Steam Flooding Boilers range from _ million kJ/h to _ million kJ/h in standard sizes.

The main advantage of the packaged boiler is its _ _.

The disadvantages of forced circulation in a boiler are the __ _ of equipment, pumps, piping, etc.

The arrangement of a once through boiler has no drums. The feed water is heated and then evaporated and superheated in through the unit.

Generally two types of draft fans are used. A _ fan supplies air to the air preheater. The preheated air (350°C) for combustion goes to the coal pulverizers and to the burners. An __ fan exhausts the combustion gases (170°C) from the air heater to the stack.

Steam generators operating above critical pressure are said to be __-critical and steam generators operating below critical pressure are classed as -critical.

The downcomers are located in the regions of the boiler, or external to the furnace altogether. The risers are located in the __ zones of the boiler, being exposed to radiant heat of the furnace or to the very hot flue gases near the furnace.

The downcomers are located in the regions of the boiler, or external to the furnace altogether. The risers are located in the __ zones of the boiler, being exposed to radiant heat of the furnace or to the very hot flue gases near the furnace.

Where electric power is used as the heating source, the boiler rating shall be the maximum kilowatt rating of the .