Table 1 reports the combustion reactions, their magnitude of enthalpy changes per mole of carbon dioxide released and the CO2 issued per GJ of energy produced by the three most common carbon-content fossil fuels: coal, oil and natural gas.
Dear Aqib,
The amount of CO2 produced when a fuel is burnt is a function of the carbon content only, while the amount of energy produced when a fuel is burnt is a function of both carbon and hydrogen content of the fuel. That is the reason why, coal (228) is associated with the enhanced amount of CO2 emitted per million Btu of energy in comparison with the natural gas (117).
Suresh Kumar Govindarajan
The hydrogen of course contributes no CO2 when burned. 12 grams of carbon combines with 32 grams of oxygen to form 44 grams of CO2. Thus the CO2 formed = 44/12 times the carbon content = 11/3 times the carbon content by weight. Typically fossil fuels yield about 12 kcal/gram, slightly more for lower-molecular-weight ones and slightly less for higher-molecular-weight ones. (The lower-molecular-weight ones contain a larger fraction of hydrogen, which yields more energy per gram when burned than does carbon.)
When fossil fuels are burned it produces energy, heat, and a wide range of waste products such as ash, slag, and other particulates. Burning fossil fuels also produces carbon dioxide, a greenhouse gas that contributes to global warming. Coal and oil also produce sulfur dioxide when burned.
According to EIA sources, the amounts of carbon dioxide (CO2)generated is in relation to the energy they produce when burned.
Coal (anthracite) 228.6
Coal (bituminous) 205.7
Coal (lignite)215.4
Coal (subbituminous)214.3
Diesel fuel and heating oil 161.3
Gasoline (without ethanol) 157.2
Propane 139.0
Natural gas 177.0
The amount of CO2 produced when a fuel is burned is a function of the carbon content of the fuel. The heat content, or the amount of energy produced when a fuel is burned, is mainly determined by the carbon (C) and hydrogen (H) content of the fuel. Heat is produced when C and H combine with oxygen (O) during combustion. Natural gas is primarily methane (CH4), which has a higher energy content relative to other fuels, and thus, it has a relatively lower CO2-to-energy content. Water and various elements, such as sulfur and noncombustible elements in some fuels, reduce their heating values and increase their CO2-to-heat contents.
That's depend on:
-Burnt quantity of fossil fuel.
-Equivelence ratio ( the amount of oxygen avalaible with respecto to the fuel amount).
-Combustion conditions (pressure, temperature..etc).
- Thermophysical properties of fuel especially the Heating Value,