Graphite, the highest grade of coal?

Graphite, the highest grade of coal?

PostBy: greygoose On: Mon Feb 17, 2014 10:21 pm

So I've been researching all the different designs of coal burners and came across some forge info where some people are making graphite crucibles for their backyard forges.
I'm wondering how it might hold up as a firebrick liner, has anyone ever tried this? I know its brittle and all, but I'm sick of replacing bricks non stop cause the anthracite is breaking the clay/ceramic ones like a mofo.

But at the same time as I look into it it's also being called the highest grade of coal, which makes sense as its almost pure carbon. I'm thinking it will be ignited when burning anthracite, but at the same time if its holding up to forge temps, maybe its far beyond any temperature flash points we can reach when burning at full capabilities in a furnace.

I'm going to test this I have some graphite blocks laying around I used to use in an EDM machine that has been broken for 20 some odd years now. even if I can use it as a secondary layer on the outermost sides it might be worth it. I'll try throwing some small pieces in on top of a raging coal fire tomorrow and see if it burns or does anything of interest and post the results.

In the production of iron, graphite blocks are used to form part of the lining of the blast furnace. Its structural strength at temperature, thermal shock resistance, high thermal conductivity, low thermal expansion and good chemical resistance are of paramount importance in this application.
greygoose
 
Hand Fed Coal Boiler: garn 2000
Hand Fed Coal Furnace: firechief 700
Coal Size/Type: nut anthracite

Re: Graphite, the highest grade of coal?

PostBy: LDPosse On: Mon Feb 17, 2014 10:36 pm

Take pics and video! I've wondered if graphite will burn, as well.
LDPosse
 
Stove/Furnace Make: DS Machine
Stove/Furnace Model: DS1500, Kozy King 100

Re: Graphite, the highest grade of coal?

PostBy: Kennebago On: Tue Feb 18, 2014 3:17 am

A number of years ago I had access to a lot of free graphite scraps and thought I would have great fuel for my coal stove. This was about the time of Chernoble so I new graphite would burn and in fact once burning was difficult to extinguish until all the fuel was gone. My problem was that getting it started was essentially impossible without a Chernoble like incident. The temp required to get it ignited and the amount of oxygen required to keep it burning were impractical in the stove i was using. The lack of volatiles means nothing except carbon to burn.

The graphite I was using was in blocks about 4" cubed. Reducing the size of the graphite to pea or buck sized, irregular shaped pieces made it is easier to use - but I did not have access to anything more than a few pounds in that size range.

I would also caution that if / when you get the graphite ignited it burns at an extremely high temperature and has the potential to wreck the grates.

I still have access to a few tons a year but all in big chunks -- hope you find a good way to use it
Kennebago
 
Stoker Coal Boiler: Coming Spring 2014
Baseburners & Antiques: Glenwood Oak / Home Grand Restoration Projects
Other Heating: Arrgghh "Oil Boiler"


Re: Graphite, the highest grade of coal?

PostBy: coaledsweat On: Tue Feb 18, 2014 8:57 pm

3000° F, not a good idea.
coaledsweat
 
Stoker Coal Boiler: Axeman Anderson 260M
Coal Size/Type: Pea

Re: Graphite, the highest grade of coal?

PostBy: Carbon12 On: Tue Feb 18, 2014 11:02 pm

Interesting. Where does one get a few tons of graphite chunks???
Carbon12
 
Stoker Coal Boiler: Keystoker KA-6
Coal Size/Type: Rice/Anthracite
Other Heating: Heat Pump/Forced Hot Air Oil Furnace

Re: Graphite, the highest grade of coal?

PostBy: Kennebago On: Wed Feb 19, 2014 12:01 am

We build large graphite molds starting with graphite logs that are 72" diameter x 72" long. They weigh about 8 1/2 tons. A lot of material hits the scrap bin as these logs are cut into the desired components. Previous activities generated even more scrap....... you can see why
i was trying to find a way to use it.... But the stuff is real difficult to make into smaller pieces... It's like free wood.... it ain't free by the time it is a useable size and I never did find a good way to burn it controllably
Kennebago
 
Stoker Coal Boiler: Coming Spring 2014
Baseburners & Antiques: Glenwood Oak / Home Grand Restoration Projects
Other Heating: Arrgghh "Oil Boiler"

Re: Graphite, the highest grade of coal?

PostBy: greygoose On: Wed Feb 19, 2014 8:32 pm

unfortunately we are having a warm snap right now so I had to let my coal die out to keep the house under 100 F, but luckily it will be dropping back down to the single digits in the next few days. I'm going to do a full clean out and test it out, I have a few hundred pounds of random scrap pieces from rice size to large plate around 2"x4"x10" and a big ol chunk I have no use for anymore. Ill make sure to take some vids on the results and post em. As far as breaking it down into smaller pieces, its about as delicate/brittle as anthracite but I cant really think of any "clean" ways to do it without shrapnel flying everywhere like unloading a bunch of 12 ga rounds into it, not free but its still a good time
greygoose
 
Hand Fed Coal Boiler: garn 2000
Hand Fed Coal Furnace: firechief 700
Coal Size/Type: nut anthracite

Re: Graphite, the highest grade of coal?

PostBy: samhill On: Wed Feb 19, 2014 10:20 pm

I'm fairly sure that they use graphite blocks for the bottoms of the blast furnaces, I guess the theory is as long as it's constantly under a molten layer of metal it doesn't really burn but keeps everything in contact hot yet the bottoms are insulated by them. Might be the same as the tiles on the space shuttles.
samhill
 
Hot Air Coal Stoker Furnace: keystoker 160
Hand Fed Coal Stove: hitzer 75 in garage
Stove/Furnace Make: keystoker/hitzer
Stove/Furnace Model: koker 160/ hitzer 75

Re: Graphite, the highest grade of coal?

PostBy: Sunny Boy On: Fri Feb 21, 2014 6:54 pm

I have casting equipment that came from a high school when it closed down the metal arts program.

The crucibles used for melting the metals in, are molded graphite.

Paul
Sunny Boy
 
Hand Fed Coal Boiler: Anthracite Industrial, domestic hot water heater
Baseburners & Antiques: Glenwood range 208, # 6 base heater, 2 Modern Oak 118.
Coal Size/Type: Nuts !
Other Heating: Oil &electric plenum furnace