Fuels and Combustion MCQs

Question 1

Yield of charcoal in high temperature carbonisation of wood is about __________ percent.

Accepted Answer

25

Answer

10

Answer

50

Answer

75

Question 2

While the first commercial low temperature coal carbonisation plant is located at Neyveli (in Chennai), the second such plant has been built at

Accepted Answer

Dankuni (West Bengal)

Answer

Dhanbad

Answer

Singreni (A.P.)

Answer

Raniganj

Question 3

The maximum adiabatic flame temperature is attained, when the fuel is burnt with

Accepted Answer

Theoretically required amount of oxygen

Answer

Theoretically required amount of air

Answer

More than theoretically required amount of air

Answer

Less than theoretically required amount of air

Question 4

To avoid fire by spontaneous combustion of coal due to its low temperature oxidation, it should be stored in

Accepted Answer

Shallow and small piles

Answer

Fine sizes without the presence of any lump

Answer

Closed space without any ventilation facility

Answer

Large heaps with small surface to volume ratio

Question 5

Which of the following is not applicable to fluidised bed combustion of coal?

Accepted Answer

It can not burn low grade coal

Answer

It achieves higher fuel combustion efficiency

Answer

Less heat transfer surface area is required in boilers

Answer

None of these

Question 6

Size of blast furnace grade coke is __________ mm.

Accepted Answer

25-80

Answer

0-15

Answer

15-25

Answer

>100

Question 7

The heat of combustion of a fuel

Accepted Answer

Is always negative

Answer

Is equal to the heat of formation

Answer

Can't be known without calculating it

Answer

Is always positive

Question 8

The ratio of % total carbon obtained in the ultimate analysis of coke and % fixed carbon obtained in the proximate analysis is always

Accepted Answer

> 1

Answer

1

Answer

< 1

Answer

Unpredictable

Question 9

Compound coke ovens are those which can be heated by

Accepted Answer

Both B and C

Answer

Both steam and electrical power

Answer

Lean gas (e.g., B.F. gas)

Answer

Rich gas (e.g., coke oven gas)