CO2 emission estimation - coal-fired boiler

[samuelliu]

Does anyone know an experimental formula to calculate the emission quantity if we only know heat value of coal?

 

[TD2K]

I don't have my copy of 'Steam, its generation and use' here at the office but I'm pretty sure they have a breakdown of coal in the back on % carbon, hydrogen, ash, etc and heating value.

I'm having some home computer problems so it might be tomorrow until I can post anything, if that book has it.

 

[TD2K]

http://www.ket.org/Trips/Coal/AGSMM/agsmmtypes.html

is just one link using Google and 'coal heating value carbon content'. Suggest you do some searching, you should be able to get a reasonable estimate though if you want a precise answer, you'll need to do an ultimate analyses on your coal.

 

[MortenA]

I assume that you also know how much coal you burn - If you also know the amount os ash produced then an estimate could be to say that the difference is C turned into CO2. The relation is then that pr. 12 grames (or punds or whatever) of coal burned 44 grames (or punds or whatever) of CO2 is generated.

This is just a rough estimate.

Best Regards

Morten

 

[MortenA]

correction to my post:

its not pr. 12 g of coal burned but pr. 12 g of "difference between coal and ash" produces 44 g of CO2

Best regards

Morten

 

[25362]

Both, TD2K and MortenA, are right. A note on volatiles.

Perry VI fig 9-1, shows the fixed C % of different coals and their thermal values. From the graph we may see that there is no linear relationship between them. For example, there is a maximum of some 15,000 Btu/lb for bituminous coal having about 70% carbon, while anthracite with some 90% C has a reported value of 14,000 Btu/lb, both with the same degree of moisture. This means that volatile material in bituminous coal contributes more to heat release than an equivalent fixed carbon % in anthracite.
Volatile material is that part of coal liberated as gases or vapours from the thermal decomposition of carbon-combined substances when heated in the absence of air.

 

[samuelliu]

Thanks for you guys' input. Can 25362 advise the TITLE of fig. 9-1? My edition may be different with you. As we known, not all carbon will be oxidized during the combustion of fossil fuels, and do you have any data for coal (bituminous)?

 

[TD2K]

Look in the index for coal Samuelliu, I have the 7th edition here and the information on coal is in chapter 27.

The 5th edition (student edition if that makes any difference) has it in chapter 9 but in both cases, it's easy to find the section.