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# Calorific Value of Volatile Material in coal

07/31/2010 7:38 AM

How to calculate the calorific Value of Volatile Material in coal

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#1

### Re: Calorific Value of Volatile Material in coal

07/31/2010 8:09 AM
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#2

### Re: Calorific Value of Volatile Material in coal

07/31/2010 9:29 AM

That table is weird, it mentions "Coal, Anthracite" and "Coal, Lignite" but not bituminous.

Lignite is also known as "Brown Coal", it's a few thousand years or a few thousand tons per square foot short of becoming coal.

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#3

### Re: Calorific Value of Volatile Material in coal

07/31/2010 12:09 PM

Govind...

Calorific values of fuel are not "calculated"....they are tested.

What are you trying to do ??

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#5

### Re: Calorific Value of Volatile Material in coal

08/01/2010 10:51 AM

Good AnswerMJCronin. Govind, You also need to clarify what it is that you mean by volatile matter. Do you mean "everything except ash?" Or do you mean everything driven off in the coke making process, leaving behind the coke?

Given the definition of coke we were given back as a pup, we think that this might be closer to what you want than the "everything but ash," But who knows?

"Coke is the solid coherent cellular residue resulting from the destructive distillation (driving off of volatile components) of Bituminous coal."

In this case the calorific value of the driven off volatiles PLUS the calorific value of the remaining coke would EQUAL the calorific value of the Original Coal. Milo

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#8

### Re: Calorific Value of Volatile Material in coal

05/23/2013 12:47 PM

Dear Mr.MJCronin,

You have referred "Calorific values of fuel are not "calculated"....they are tested."

"they are tested." Do you mean the testing is for the Calorific Value DIRECTLY in a bomb calorimeter or some other device (OR) testing for the CONSTITUENTS of FUEL for its Carbon, Hydrogen, Oxygen, Sulphur, Moisture, Non-combustibles, - i.e. ULTIMATE ANALYSIS and from the constituents we can calculate the GROSS CALORIFIC VALUE and NETT CALORIFIC VALUE.

The Chemical Engg.Books by McCab and Smith, or Richardson & Coulson, or Badger and Banchero give full details of Heat Liberated by the COMBUSTIBLES when full combustion is completed, and this is governed by STOICHOMETRIC RELATIONS of the constituents of the fuel.

12C + 32 O2 = 44 CO2 , on FULL COMBUSTION will release 14,000 BThu. of Heat or 14,000 x 1.055 = 14,770 KJoules

1H2 + 8O2 = 9H2O, on FULL COMBUSTION, will release 69,000 BThu. of Heat or 69,000 x 1.055 = 72,795 KJoules

Similarly Sulphur also will release heat ( I do not remember the Heat Value).

These HEAT VALUES are to be MULTIPLIED BY THE PERCENTAGE of CONSTITUENTS of the Fuel, and sum up for Total Heat.

If moisture is there in the fuel, the nett heat available will be reduced.

Hence I presume that you refer testing as ANALYSIS. Pl.confirm.

DHAYANANDHAN.S

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#4

### Re: Calorific Value of Volatile Material in coal

07/31/2010 2:31 PM

Dear Govind Rao, MJCronin is correct, in addition, testing methods and procedures differ by local. In Germany I believe it would be in this form Q=Vn ΔHhc -hope this helps I don't know where in the world the republic of PA is... next to the commonwealth of PA I suppose.

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#6

### Re: Calorific Value of Volatile Material in coal

08/02/2010 12:08 AM

No need. Look it up in Kempe's Engineers' Yearbook, any edition.

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#7

### Re: Calorific Value of Volatile Material in coal

08/20/2010 10:01 AM

Kinldy send me a formular of different formulae with the units, to calculate the calorific Value of Volatile Material in coal after charring the in MJ/kg. This would be at higher temperatures than 900°C. Please e-mail to carpedsd@eskom.co.za

Regards

Deborah

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