The adiabatic flame temperature of a fuel depends upon the initial temperature of___________________?
Show answer Hide answer
Answer: C. Both A. & B.
Explanation
Adiabatic flame temperature depends on the initial enthalpy and temperature of the fuel. Initial temperature of the combustion air also contributes significant sensible heat energy. Energy balances require accounting for all reactant sensible and reaction heat inputs. Adiabatic flame temperature assumes complete combustion with zero heat loss to surroundings. Preheating combustion air raises the final theoretical flame temperature in furnaces. Thermodynamic enthalpy of formation tables are used to calculate maximum flame temperatures.
Furnace design engineers calculate adiabatic flame temperatures to select refractory materials. Air preheaters improve industrial boiler thermal efficiency by raising reactant temperatures. Metallurgical processes require high flame temperatures achieved through oxygen enrichment. Fuel temperature alone ignores the substantial thermal contribution of combustion air. Air temperature alone neglects the initial energy content of the burning fuel. Neither option is incorrect because both fuel and air initial temperatures matter.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
Related questions
Q1. Which category of coal is efficiently combusted using travelling grate stokers______________?
Show answer Hide answer
Answer: C. Non-caking
Non-caking coals do not agglomerate or fuse together on moving furnace grates. Traveling grate stokers require uniform fuel beds for effective air distribution. Absence of swelling prevents clinkers and maintains continu...
Q2. Abel apparatus measurements apply to oils with flash points around ___________°F.
Show answer Hide answer
Answer: A. < 120
Abel closed cup apparatus measures flash points below one hundred twenty degrees Fahrenheit. Low flash point petroleum products require precise measurement for transport safety. Standardized testing protocols ensure reli...
Q3. Burning hydrocarbon fuels containing high sulfur levels with 40% excess air yields flue gas with significant carbon monoxide due to_________________?
Show answer Hide answer
Answer: D. Lack of thorough mixing of fuel with air
Carbon monoxide in flue gas indicates incomplete combustion despite excess air presence. Lack of thorough mixing between fuel and oxygen prevents complete oxidation to carbon dioxide. Poor burner aerodynamics create loca...
Q4. Raw coke oven gas contains approximately _____________ gm/Nm3 of ammonia.
Show answer Hide answer
Answer: B. 5
Ammonia is released from the nitrogen compounds in coal during the carbonization process. Industrial measurements show typical raw gas concentrations hover around five grams per cubic meter. Chemical scrubbing systems ar...
Q5. What are the primary applications of anthracite coal___________________?
Show answer Hide answer
Answer: D. All A., B. and C.
Anthracite possesses very high fixed carbon content making it ideal for recarbonising steel. Its pure carbon structure allows manufacturers to produce high-grade carbon electrodes efficiently. Blending anthracite helps c...
Q6. Why is high ash content undesirable in coal________________?
Show answer Hide answer
Answer: D. All A., B. and C.
Mineral ash particles act as abrasive agents that rapidly wear down pulverizer grinding elements. Molten ash can flux refractory linings by penetrating porous surfaces inside high-temperature furnaces. Ash components ret...