Furnace Technology MCQs

Question 1

In furnaces operating at very high temperature (say) 1250°C, e.g. soaking pit), the maximum heat transfer takes place by

Accepted Answer

Radiation

Answer

Conduction

Answer

Convection

Answer

Can not be predicted

Question 2

The reason for excessive clinker formation in gas producers is the

Accepted Answer

All of the above

Answer

Use of coal/coke containing a high % of fines and ash

Answer

Use of fuel having too low an ash fusion temperature

Answer

Development of hot spots in the fuel bed and an abnormally high rate of gasification

Question 3

In a muffle furnace, the muffle

Accepted Answer

All of the above

Answer

Retards the heat transfer

Answer

Assists in temperature equalisation in the charge

Answer

Permits the use of controlled atmosphere for the protection of stock

Question 4

Example of an indirectly heated furnace is

Accepted Answer

Both A and B

Answer

Hood annealing furnace

Answer

Muffle furnace

Answer

Neither A nor B

Question 5

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

Accepted Answer

Accelerates the burning rate and economises on fuel consumption

Answer

Permits the use of high ash content coal

Answer

Permits the use of low fusion point ash coal

Answer

All of the above

Question 6

Tunnel kilns are usually used for

Accepted Answer

Drying/tempering of refractories

Answer

Roasting of pyrites

Answer

Reheating of slabs

Answer

Melting of glass

Question 7

Which of the following is not a directly fired furnace?

Accepted Answer

By-product coke oven

Answer

Calcination kiln

Answer

Sintering furnace

Answer

Open hearth furnace

Question 8

Test specimen for determination of refractoriness under load (RUL) of a refractory is heated in a

Accepted Answer

Carbon resistance furnace

Answer

Furnace employing neutral atmosphere

Answer

Reducing atmosphere

Answer

Furnace employing negative pressure

Question 9

Thermal efficiency of furnaces can be improved by

Accepted Answer

All of the above

Answer

Waste heat recovery from flue gas

Answer

Minimising heat losses from furnace walls

Answer

Maintaining proper draught