Which of the following furnaces will have maximum thermal efficiency ?
(A) Soaking pits
(B) Walking beam reheating furnace
(C) Boiler furnace
(D) Rotary kilns
The function of an economiser in a boiler is to preheat the _____________________?
(A) Feedwater
(B) Combustion air
(C) Pulverised coal
(D) Furnace oil
Which of the following is not an additive for flue gases from furnace to reduce its dewpoint ?
(A) Ammonia
(B) Fine dolomite
(C) Alkaline powders
(D) None of these
Out of the following fuels used in a furnace exhausting flue gas at a temperature of 600°C, the percentage stack loss will be maximum in case of complete combustion of_________________?
(A) Furnace oil with air
(B) Furnace oil with oxygen
(C) Blast furnace gas with air
(D) Blast furnace gas with oxygen
Fuel economy in an industrial furnace operation cannot be achieved by the use of__________________?
(A) Stoichiometric combustion air
(B) Non-preheated combustion air
(C) Combustion air not enriched with oxygen
(D) Recuperators
Pick out the wrong statement ?
(A) A ceramic material which becomes fluid upon heating and can be moulded in liquid/viscous state is termed s glass
(B) Ceramic materials do not undergo vitrification on heating
(C) Ceramic materials are brittle in nature
(D) Non-oxide ceramic materials generally act as a semi-conductor
Pick out the wrong statement?
(A) Fluxing material like lime is added in clay to reduce the vitrification temperature
(B) Main constituents of clay are alumina and silica
(C) Addition of sand in ceramic materials makes it non-plastic, increases its fusion point and reduces its shrinkage on burning
(D) Vitrification of fireclay material is done to increase its porosity
Which furnace employs preheating, heating and soaking zones ?
(A) Soaking pit
(B) Reheating furnace
(C) Open hearth furnace
(D) Cupola
Reaction of anhydrous liquid ammonia with ortho-phosphoric acid produces____________________?
(A) Ammonium phosphate
(B) Superphosphate
(C) Triple superphosphate
(D) None of these
In ammonia synthesis (N2 + 3H2 = 2NH3), there is a decrease in total volume, hence to get high equilibrium conversion, the reaction should be carried out at________________?
(A) Low pressure
(B) High pressure
(C) Very high temperature
(D) Atmospheric pressure; as the pressure has no effect on conversion