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. None of these >71% < 37% In between 37 & 71% None of these >71% < 37% In between 37 & 71% ANSWER DOWNLOAD EXAMIANS APP
Fuels and Combustion Preheating of __________ the flame temperature. The gaseous fuel before combustion decreases Either the fuel or the air does not affect Combustion air decreases Either the fuel or the air or both, increases The gaseous fuel before combustion decreases Either the fuel or the air does not affect Combustion air decreases Either the fuel or the air or both, increases ANSWER DOWNLOAD EXAMIANS APP
Fuels and Combustion Fusion point of coal ash generally varies from 1000 to 1700° C. Ash having fusion point less than __________ °C is liable to form clinker. 1400 1250 1100 1350 1400 1250 1100 1350 ANSWER DOWNLOAD EXAMIANS APP
Fuels and Combustion The main function of primary air in pulverised coal fired burner is to Dry and transport the coal Burn CO to CO₂ Have proper combustion by supplying it around the burner Preheat the tertiary air used for complete combustion of CO to CO₂ Dry and transport the coal Burn CO to CO₂ Have proper combustion by supplying it around the burner Preheat the tertiary air used for complete combustion of CO to CO₂ ANSWER DOWNLOAD EXAMIANS APP
Fuels and Combustion A good coking coal should have high __________ content. None of these Moisture Sulphur & phosphorus Ash None of these Moisture Sulphur & phosphorus Ash ANSWER DOWNLOAD EXAMIANS APP
Fuels and Combustion A liquid/gaseous fuel containing hydrocarbons and high amount of sulphur is burnt with 40% excess air. The flue gas still contains large amount of carbon monoxide. This may be due to the High sulphur content in the fuel Low calorific value of the fuel Lack of thorough mixing of fuel with air Presence of large quantity of hydrogen in the fuel High sulphur content in the fuel Low calorific value of the fuel Lack of thorough mixing of fuel with air Presence of large quantity of hydrogen in the fuel ANSWER DOWNLOAD EXAMIANS APP