Fuels and Combustion Explosion limit of blast furnace gas is 37 to 71% gas in gas-air mixture. It means that the blast furnace gas will explode when burnt in a confined space, if its concentration in the gas-air mixture is __________ percent. < 37% >71% None of these In between 37 & 71% < 37% >71% None of these In between 37 & 71% ANSWER DOWNLOAD EXAMIANS APP
Fuels and Combustion In high temperature carbonisation (as compared to low temperature carbonisation) of coal, the Gas yield is less Ignition temperature of coke produced is less Aromatic content of tar produced is more Tar yield is more Gas yield is less Ignition temperature of coke produced is less Aromatic content of tar produced is more Tar yield is more ANSWER DOWNLOAD EXAMIANS APP
Fuels and Combustion Which of the following would require least amount of secondary air for combustion? Semi-bituminous coal containing 25% ash and 20% volatile matter Anthracite containing 10% volatile matter and 8% ash Coke breeze containing 25% ash and 2% volatile matter Bituminous coal containing 20% ash and 25% volatile matter Semi-bituminous coal containing 25% ash and 20% volatile matter Anthracite containing 10% volatile matter and 8% ash Coke breeze containing 25% ash and 2% volatile matter Bituminous coal containing 20% ash and 25% volatile matter ANSWER DOWNLOAD EXAMIANS APP
Fuels and Combustion Coke oven gas is a better fuel than blast furnace gas, because of its higher Heat release rate (thus requiring smaller combustion chamber) All of these Calorific value, cleanliness and relatively low distribution cost (due to its low specific gravity) Adiabatic flame temperature Heat release rate (thus requiring smaller combustion chamber) All of these Calorific value, cleanliness and relatively low distribution cost (due to its low specific gravity) Adiabatic flame temperature ANSWER DOWNLOAD EXAMIANS APP
Fuels and Combustion Presence of phosphorous in metallurgical coal Badly affects the quality of steel Is not undersirable Reduces its calorific value Increases its caking power Badly affects the quality of steel Is not undersirable Reduces its calorific value Increases its caking power ANSWER DOWNLOAD EXAMIANS APP
Fuels and Combustion Naphthalene recovered from coke oven gas is used For making electrodes As a fuel in furnaces As moisture proof coating on fibres As moth balls (insecticides) For making electrodes As a fuel in furnaces As moisture proof coating on fibres As moth balls (insecticides) ANSWER DOWNLOAD EXAMIANS APP