Furnace Technology MCQs

Question 1

Amount of coal lost in ash particle, which is carried through the boiler system, depends upon the

Accepted Answer

All of the above

Answer

Physical nature, ash content and fineness of the coal

Answer

Amount of excess air supplied and load on the boiler

Answer

Type of burner and combustion chamber

Question 2

Which of the following accentuates clinker-ing troubles on furnace grate burning coal?

Accepted Answer

All of the above

Answer

Low reactivity of carbonised residue containing high proportion of iron & sulphur

Answer

Low forced draft & fuel bed temperature

Answer

Thick firebed and preheated primary air

Question 3

Ostwald charts are meant for

Accepted Answer

Computing the excess/deficiency of combustion air

Answer

Calculation of flue gas temperature

Answer

Computation of flue gas analysis

Answer

None of these

Question 4

Which one is not an induced draught furnace?

Accepted Answer

Blast furnace stove

Answer

Sintering furnace

Answer

High pressure boiler

Answer

None of these

Question 5

In which of the following furnaces, the gases are sucked through the stock bed from below?

Accepted Answer

Sintering machine

Answer

Soaking pit

Answer

Beehive oven

Answer

None of these

Question 6

A refractory wall separating the stock and the source of heat is provided in a

Accepted Answer

Muffle furnace

Answer

Updraft kiln

Answer

Continuous furnace

Answer

None of these

Question 7

Pick out the wrong statement.

Accepted Answer

None of these

Answer

Addition of methane to the furnace atmosphere reduces decarburising by hydrogen

Answer

Nitrogen in presence of steam decar-burises high carbon steel, whereas hydrocarbon gases carburise the surface of steel at annealing temperatures

Answer

Active nitrogen (formed by cracking ammonia at the metal surface) cause nitride formation with increase in surface hardness

Question 8

While the fuel fired furnace can be used upto a maximum temperature of about 1700°C, the electric furnace can be used upto a temperature of about __________ °C.

Accepted Answer

4500

Answer

2000

Answer

3000

Answer

6000

Question 9

In a furnace, the heat taken by the charge/stock and the heat lost to the furnace structure & flue gases depends on the

Accepted Answer

All of the above

Answer

Rate of firing and emissivity of flame

Answer

Thermal conductivity of the charge & structural materials of furnace

Answer

Nature of process ; whether batch, continuous or intermittant