Chemical composition of Bunker C fuel oil (Oil N¦ 6)

[21121956]

Hello everybody

I have been trying (without results) to find information regarding with the chemical composition of Bunker C fuel oil (grade Nº6); in order to achieve some combustion calculations and related subjects.

Can somebody help me, please, with this task?

 

[21121956]

Please visit thread794-132167 and thread481-133221, and you will find interesting information about this subject.

Thanks

 

[mbeychok]

21121956:

It is not quite clear what you mean by "combustion calculations and related subjects". If all you are trying to do is arrive at the amount of flue gas and its composition, then there really isn't too much difference between various fuels. For example:

(1) An 18 molecular weight natural gas combusted with 12% excess air yields 11,600 scf of wet flue gas per 10⁶ Btu of fuel, and that flue gas contains 8.8 vol% CO2, 2.0 vol% O2, and has a molecular weight of 27.7

(2) A 15.5 °API fuel oil with a carbon/hydrogen ratio of 8.1 by weight combusted with 15% excess air yields 11,930 scf of wet flue gas per 10⁶ Btu of fuel, and that flue gas contains 12.4 vol% CO2, 2.6 vol% O2, and has a molecular weight of 29.0

(3) A coal (containing 47.9 wt % carbon, 3.4 wt% hydrogen, 10.8 wt% oxygen, 6.0 weight % ash, and 30.4 wt% moisture) combusted with 20% excess air 13,985 scf of wet flue gas per 10⁶ Btu of fuel, and that flue gas contains 13.5 vol% CO2, 3.3 vol% O2, and has a molecular weight of 29.0

The scf in the above data means standard cubic feet measured at 60 °F and 1 atmosphere.

As you can see, the amount of flue gas does not vary drastically whether using gas, fuel oil or coal. Hence, you can assume there will be even less variation from one heavy fuel oil to another.

For more details of the above examples, visit:
www.air-dispersion.com/formulas.html#combustion

Milton Beychok
(Contact me at www.air-dispersion.com)
.

 

[25362]

thread481-133221​

 

[bonzoboy]

I checked my database, and residual fuels have around 87% carbon, and 11%-13% hydrogen. The difference is the amount of fuel bound nitrogen in the fuel, and any residual ash. If you assume say 1/2% nitrogen, you can assume 12.5% hydrogen, and calculate a heating value using Boies Formula