Fuels and Combustion MCQs

Question 1

Eschka mixture, which is used for the determination of sulphur in coal, is a mixture of

Accepted Answer

MgO & Na2CO3

Answer

MgSO4 & BaCl2

Answer

BaSO4 & NaCl

Answer

MgCO3 & NaCl

Question 2

__________ prohibits the use of alcohols directly in petrol engines.

Accepted Answer

High cost & availability

Answer

Low octane number

Answer

Low flash point

Answer

Low calorific value

Question 3

Gross and net calorific value of a fuel will be the same

Accepted Answer

If its hydrogen/hydrogen compound content is zero

Answer

If its ash content is zero

Answer

Ifits carbon content is very low

Answer

Under no circumstances

Question 4

Out of the following fuels, the difference between gross and net calorific value will be minimum in case of

Accepted Answer

Blast furnace gas

Answer

Coke oven gas

Answer

Water gas

Answer

Natural gas

Question 5

Desirable "Micum Index" values of metal-lurical coke are

Accepted Answer

M40 > 78% and M10 < 10%

Answer

M40 > 4% and M10 < 80%

Answer

M40 > 10% and M10 < 78%

Answer

M40 > 98% and M10 < 2%

Question 6

Caking index of the coal blend used for the manufacture of metallurgical coke should be around

Accepted Answer

21

Answer

5

Answer

40

Answer

48

Question 7

Height of coke oven is limited (say maximum upto 7 metres) mainly by the

Accepted Answer

Problem of uniform heating along its height

Answer

Structural strength of silica bricks

Answer

Problem in door cleaning

Answer

Buckling of ram of pusher car at the time of coke pushing

Question 8

Which of the following fuels is generally not used in thermal power plant boiler firing?

Accepted Answer

Pulverised coking coal

Answer

Furnace oil, light diesel oil and tar/PCM

Answer

Coal middling from washeries

Answer

B.F. gas, coke oven gas and L.D. converter gas

Question 9

Bulk density of pulverised coal may be about __________ kg/m3.

Accepted Answer

500

Answer

100

Answer

1000

Answer

1500