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Heat of combustion CNCG

Heat of combustion CNCG

Heat of combustion CNCG

(OP)
Does anyone know how to calculate heat of combustion for CNCG gas mixtures ?

LB

RE: Heat of combustion CNCG

I though CNCG meant concentrated non condensable gas, as such we would need to know what you CNCG composition is to give a correct answer.  Unless someone out there knows of a standard rough figure that is typical of some streams??

Cheers,

RE: Heat of combustion CNCG

(OP)
The composition is:
(CH3)2S: 1 % , N2 : 67 % , H2O: 13 % , H2S : 15 %, CH3SH : 4 %. ( % by volume).

Regards

LB

RE: Heat of combustion CNCG



The combustibles are the sulfides: hydrogen, methyl and dimethyl. Use their heats of combustion per unit volume (or mol), multiply them by their vol% (ie, mol% as for an ideal gas mix), and add the results.

RE: Heat of combustion CNCG

(OP)
Thank's "25632" for your reply.
But where can I find the heat of combustion for these sulfides ?

Regards

LB

RE: Heat of combustion CNCG

If you cannot find them, these can be estimated as the sum of the standard heats of formation of SO2, H2O, CO2 resulting from stoichiometric combustion with oxygen plus the (negative) standard heat of formation of the chemical itself.

An example for dimethylsulfide considering water is condensed back as a liquid at 25 deg C and all other gases are returned to 25 deg C (standard state):

C2H6S + 4.5 O2 => 2 CO2 + 3 H2O +  SO2

The heat of combustion and standard heats of formation are given in kJ/mol.

carbon dioxide: 2×393.51 =  787.02
water: 6×142.915 =            857.49
sulfur dioxide: 1×296.8 =     296.80
dimethyl sulfide:                  -37.40

total heat of combustion,    1903.91

Similarly for hydrogen sulfide and methyl mercaptan.
Then, multiply the heats of combustion by their vol%, and add the results. Kindly check my calculations.

RE: Heat of combustion CNCG

(OP)
"26352" ,

Thank you very much ! Yoy have helped me a lot.

Best regards

LB

RE: Heat of combustion CNCG

LB:

I don't know where your CNCG will be combusted. If it is anywhere in the USA, I hope you realize the environmental permitting problems you will encounter for burning a gas that contains 15 volume percent H2S and 5 volume percent of organic sulfides.

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

RE: Heat of combustion CNCG

(OP)
mbeychok,
This is a plant in Europe with a special combustion furnace.

LB

RE: Heat of combustion CNCG

LB:

You should be aware that, in many European countries, there will be restrictions on the amount and/or concentration of SO2 which you will be permitted to emit to the atmosphere. You may have to provide a flue gas scrubber to remove SO2.

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

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