[TheForge] Coal clumping

[xlch58 at swbell.net]

I am guessing it is the impurities in the coal that cause the clumping.  
When I buy metallurgical coke and bust it into pellet size, it does not 
clump and I cannot form the little welding cave I like, but I get no 
slag at all.  The bituminous coal I get readily clumps and also readily 
forms slag.   I am guessing that minute bits of "slag" are gluing the 
coke formed from bituminous coal together, probably silica.

Charles

Bruce Freeman wrote:
> So, the follow-up question is why DOESN'T this happen for charcoal or anthracite.  Well, I don't know.  It may be because these don't swell when heated and hence don't expose new surface.  
>
> Hope this helps.
>
> Bruce
> NJ
>
>   
>>>> trollkeep at gmail.com 4/23/2007 1:51 PM >>>
>>>>         
> I was asked at a 4-H Blacksdmithing class why the coal clumps up when
> it converts to coke.  As odd as it may seem I did not have the
> slightest idea.  Does anyone know in terms that I can at least convert
> for a ten year old?
>
> David Childress
> Rocky Forge Blacksmith Guild
>