FUELS AND COMBUSTION QUIZ

A sample of natural gas containing 80% methane (CH₄) and rest nitrogen (N₂) is burnt with 20% excess air. With 80% of the combustibles producing CO₂ and the reminder going to CO, the Orsat analysis in volume percent is

CO₂ : 7.42, CO : 1.86, O₂ : 4.64, N₂:86.02

CO₂ : 6.39, CO : 1.60, O₂ : 3.99, H₂O:25.96, N₂:72.06

CO₂ : 7.60, CO : 1.90, O₂ : 4.75, N₂ : 85.74

CO₂ : 6.26, CO : 1.56, O₂ : 3.91, H₂O :15.66, N₂ : 72.60

TRUE ANSWER : ?
YOUR ANSWER : ?

Coking time in beehive coke oven is about

2-3 days

One week

Two weeks

12 hours

TRUE ANSWER : ?
YOUR ANSWER : ?

Natural draft created by the chimney depends upon

Both A & B

Neither A nor B

Its height

Temperature of the flue gas

TRUE ANSWER : ?
YOUR ANSWER : ?

Low temperature oxidation and spontaneous combustion of freshly mined coal is accentuated, if

It is stored in tall heaps

Smaller fines are stored in large quantity

All of these

It contains large amount of volatile matter

TRUE ANSWER : ?
YOUR ANSWER : ?

Gross calorific value will be equal to the net calorific value for

CO

C₂H₂

H₂

C₂H₆

TRUE ANSWER : ?
YOUR ANSWER : ?

Gobar gas is produced by the __________ of cown dung.

None of these

Fermentation

Hydrogenation

Oxidation

TRUE ANSWER : ?
YOUR ANSWER : ?

The advantage of firing pulverised coal in the furnace lies in the fact, that it

Permits the use of high ash content coal

Accelerates the burning rate and economises on fuel combustion

Permits the use of low fusion point ash coal

All of these

TRUE ANSWER : ?
YOUR ANSWER : ?

Orsat apparatus is meant for

Direct determination of nitrogen in flue gas by absorbing it in ammoniacal cuprous chloride

Finding out combustion efficiency

Gravimetric analysis of flue gas

None of these

TRUE ANSWER : ?
YOUR ANSWER : ?

Use of preheated air for combustion of fuel in the furnace, increases the

Scale losses of the furnace stock

None of these

Flame temperature

Calorific value of the fuel

TRUE ANSWER : ?
YOUR ANSWER : ?

Critical Air Blast (CAB) value of coke is a direct measure of its

Reactivity

None of these

Strength

Hardness

TRUE ANSWER : ?
YOUR ANSWER : ?