[TheForge] Pocahontas Coal

[Dave Brown]

At 22:02 04/19/02 -0400, you wrote:
>Only difference I saw between Cumberland Elkhorn and Pocahontas was that 
>the CE
>seemed to be a bit more smoky. Otherwise I have them even.

Bob,

The most significant difference between the two can be seen in their levels 
of fixed carbon and volatiles between Pocahontas #3 and the Cumberland 
Elkhorn.  There's about twice as much volatile matter in CE than in the P3 
and that makes a big difference.  "Volatile matter" are the oils and tars 
(hydrocarbons) that boil off and burn rapidly and make the flame and 
smoke.  What is left is essentially the coke/breeze or fixed carbon 
component.  If all you are comparing is the ability to heat a piece of 
steel, then burning carbon is burning carbon and heat is heat and you won't 
necessarily see the difference.  It's what you don't see that also matters.

A comparison below of the two for carbon, hydrogen, volatile matter, and 
Btu content points out where most the difference lies.

         P3      CE

%VM     18.7    38.1
%C      90.7    83.2
%H       4.1     5.4
BTU/#   15,730  14,820

Yes, I know that the % above add up to more than 100%, but that's because 
much of the hydrogen is tied to some of the carbon and makes up much of the 
volatile matter and is sent up the flue as smoke (soot/carbon) and unburned 
hydrocarbons.  The CE has less carbon overall and twice as much carbon 
contained in the volatile hydrocarbons.  The result is less coke/breeze 
formation per pound of coal burned, and it's the coke/breeze that we want 
in the heart of the fire.

The P3 also has a Free Swell Index (aka Coke Button) of 8-9 where the CE 
has a FSI of only 3, which relates to coke formation.  This means more 
carbon burning in the heart of the fire where you want it and less up the 
chimney as fire and smoke where it doesn't do you any good.

There's a lot more in the differences in composition of these two coals 
that contribute, but it's probably much more than you want to know and more 
than I feel like writing.  But the above stuff is the critical stuff.

Don't get me wrong, CE is good blacksmithing coal and beats the snot out of 
a lot of other coal sources.  But it is still a ways short of P3 in my 
book.  Given the choice, the P3 is well worth the difference in price ... 
when you can get it bulk that is.  P3 is also a much better buy in bags 
from Skei at $400/ton than is the CE from Centaur Forge at $880/ton (plus 
shipping on both).  A truckload of P3 to Wisconsin is about $150/ton <give 
or take a little>, CE is not much less.  (shipping/freight cost is at least 
half of this delivered cost)

Dave Brown