Fuels and Combustion Spontaneous combustion of coal on storage results due to Inadequate ventilation Storage in large heaps with small surface to volume ratio Low temperature oxidation All of these Inadequate ventilation Storage in large heaps with small surface to volume ratio Low temperature oxidation All of these ANSWER DOWNLOAD EXAMIANS APP
Fuels and Combustion Prime coking coal is always blended with medium or non- coking coal before ear-bonisation Because, it alone produces unreactive coke Both A & B Neither A nor B To check against its excessive swelling during heating, which may exert high pressure and damage coke oven walls Because, it alone produces unreactive coke Both A & B Neither A nor B To check against its excessive swelling during heating, which may exert high pressure and damage coke oven walls ANSWER DOWNLOAD EXAMIANS APP
Fuels and Combustion Combustion of pulverised coal compared to the lumpy coal Provides better control of furnace temperature Facilitates combustion with lower excess air Provides higher thermal efficiency & flame temperature All of these Provides better control of furnace temperature Facilitates combustion with lower excess air Provides higher thermal efficiency & flame temperature All of these ANSWER DOWNLOAD EXAMIANS APP
Fuels and Combustion For which pair of the fuel gases, calorific value (C.V.) of one fuel is almost double that of the other on volume basis (i.e., kcal/Nm³ ), while the C.V. is same on weight basis (i.e., kcal/kg) ? Propane and acetylene Propane and LPG Sewage gas and gobar gas F. gas and coke oven gas Propane and acetylene Propane and LPG Sewage gas and gobar gas F. gas and coke oven gas ANSWER DOWNLOAD EXAMIANS APP
Fuels and Combustion Presence of phosphorous in metallurgical coal Is not undersirable Badly affects the quality of steel Reduces its calorific value Increases its caking power Is not undersirable Badly affects the quality of steel Reduces its calorific value Increases its caking power ANSWER DOWNLOAD EXAMIANS APP
Fuels and Combustion Size of blast furnace grade coke is __________ mm. >100 15-25 0-15 25-80 >100 15-25 0-15 25-80 ANSWER DOWNLOAD EXAMIANS APP