When I was kid, I used to pick up pieces of coal I would find along the railroad. Being a kid, and curious, I would try to light the coal, but never could get it to burn.
My Q is: How do you get real coal to burn? (not CHAR-coal)
I’m sure Anthracite can give you a more detailed answer. But in coal-fired electric generating plants, the coal is pulverized into a fine powder, then injected into the burners and ignited.
It’s often useful to start the fire with something like newspaper–not to mention it’s better if you have a larger pile of coal, rather than a single piece. We used to use coal-burning stoves at Scout camp. Lovely smell.
LL
I almost suspect this is a “mercy thread”, that is, one to give me a chance to talk about coal more. I guess I need it, since once again no one thinks enough of me to put me on one of their latest “lists”…
Anyhow, MSK, I would hazard a guess that the coal you found was one of two types:
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It was a low-volatile bituminous coal, which is somewhat difficult to start burning unless you add it to a wood or hot paper fire, or
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It was a coal which had laid out in the sun by the tracks for a while, and had devolatized in the heat, thus making it more diffcult to burn.
Coal on a proximate basis is made up of 4 main constituents:
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Fixed carbon - technically, carbon and hydrocarbon char - this does not burn very easily, but produces lots of heat when it does burn.
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Volatile matter - this is the lighter hydrocarbons of the coal. These will devolatize from the coal, that is evaporate away as it heats, and high amounts of these allow easy starting of combustion.
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Ash, which is non-combustible (mostly…)
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Moisture.
Coals are ranked by the ASTM essentially on the basis of their volatile matter content to a point, then by their heating value (or energy released during combustion) after that.
Anthracite is the least volatile of all coals, and can be very difficult to start burning. Bituminous coals come next, and range from very low to highly volatile type. Subbituminous coals contain an even higher ratio of volatile matter to fixed carbon, and lignites are the worst of all coals, where there is so much moisture and ash in them that you are burning something close to peat.
Subbituminous coals, such as those of Wyoming in the Powder River Basin, are so high in volatiles and moisture that they spontaneously combust on the coal piles at plants unless the yard operators keep packing it down tight. I’ve seen PRB coal self-ignite many times, so you probably didn’t find that. It even arrives by train and barge on fire sometimes - I was in Tennessee watching the operators at Johnsonville unload a barge that looked like a giant luau pit once! All it needed was a few pigs, some pineapples,…
So the short answer to your question is that it probably was a low-medium volatile bituminous coal, or an old piece of coal. I doubt it was anthracite, as that is not used very commonly in the last 15 to 20 years or so - at least not shipped by rail.
As to how coal is typically burned for electricity and process steam…
Coal in power plants is burned in one of two ways. In a pulverized coal power plant, as noted by oliversarmy, the coal is ground to an extremely fine powder and blown into the furnace by fans, where it ignites almost like a gas flame. These powder particles are normally fine enough to pass 70% or more through a 74-micron hole screen.
The second way in which it is commonly burned is by cyclone power plants. In a cyclone plant, the coal is crushed to a size of about 1/4 inch or so, and burned in special barrel-shaped burners (called, ironically, “cyclones”) which feed into a larger furnace.
Of course there are other ways (fluidized bed, integrated gasification combined cycle, etc.) but these don’t amount to squat for the amount of generation produced.
There.
Anthracite, could you tell me about jet? I remember old buttons made of this, but i never see anything new made of jet. Is it difficult to carve?
Some folks still heat with coal, don’t they? How is it burned in furnaces or fireplaces? I’m sure furnaces use some sort of feed device to keep the flame burning, but how do you start it? Are there automatic ignition coal furnaces or do they all have to be started manually?
I had a friend who lived in England for a while. He told me something about heating his home with coal, but I forget everything except that it burns a lot hotter than wood or charcoal.
~~Baloo
Jet is highly polished very low-volatile coal. It is either a very low volatile bituminous coal, or an anthracite - IIRC there is no “fixed” specification for the class of coal that must be used. They use whatever will work with being hard enough, and low-volatile enough.
However, if you search on the web, you will find many different, but similar definitions for “jet”. One site calls it “similar to amber, but made from fossilized trees, not their sap”. Another calls it somply a “natural mineral”. A third calls it “highly compacted coal” (which is essentially anthracite), and a fourth refers to jet glass, which is related to jet in being “glass impregnated with coal dust”. It’s coal, folks.
You can find jet jewelry still at places like rock shops, new age crystal and jewelry shops, and so forth. IMO they charge much too much for it - the coal it is made from is at most $35/ton, and it is very easy to form and shape. I haven’t seen new jet buttons ever.
I have looked myself for good jet jewelry (why wouldn’t the Coal Lady wear it?) but have not found any really “classy” looking pieces. Most is mounted in silver, or is not shaped very well, or set with turquoise (blech!). Jet is very soft relative to other jewelry, and if you have it you should make sure it doesn’t get scratched by other items in your armoire.
I actually don’t know much about home use of coal - it is still used occasionally by hobbyists and traditionalists. Home heating coal is typically low-sulfur anthracite, which has become very expensive and hard to find in some areas of the US (well, if $50/ton is what you call expensive) I don’t really know how a large home furnace fed it’s coal, if it was just shoveled in on a grate or what.
It does burn a bit hotter than wood or charcoal, which is why you need to have some caution if you try to burn it in a wood stove. There was a thread about this in the last couple days here as well:
Most homeowners don’t have the time or inclination to feed their coal furnaces by hand, so the furnace uses a stoker. There are many types of stokers, but the most common are the screw-type and the ram-feed. Both are used with mechanized grates and retorts to bank and spread the fire and remove ash and clinkers(unburned chunks of coal and ash).To start a coal furnace you usually have to start a fire with paper and rags at the beginning of the heating season. Hope that helps, and I’m sure Anthracite will be along to correct any mistakes I made.
I’m glad you posted, Chief. I didn’t know that home furnaces used mechanized stokers - that would be kinda cool to have one actually. I know all about industrial and utility coal use, including industrial stokers, but am somewhat ignorant on home coal use.
I had a coal stove which heated the house via a back-boiler when I lived in North Wales (traditional coal mining area - in the autumn, when you got a temperature inversion, you could walk up the hill towards home and suddeny you’d hit the coal smoke layer. Beautiful).
I was given instructions by the previous tenant on how to light it & how to get it stay alight (& how to get it to stay alight overnight - the really important one!).
It didn’t have a mechanised stoker, but then it wasn’t a furnace. I don’t know anyone who did have one. I do knwo I spent a lot of time hacking pallets up for kindling!
Basically the stove had a vent & you used to semi close it when lighting, as too much air flow put the fire out. You’d light newspaper & add kindling (thin bits of light wood - forgive me if I seem patronising, I’m just trying to be thorough). When this has got going, you would add about half a shovel of anthracite - good, black coal. We were always taught in geography that this was the best sort - less sulphur fumes from burning too. Close the stove door to make sure the airflow is right & watch it till the coal catches light. Then add a few shovels at the time (not too much or you block the airflow) and open up the airvent more.
When it really got going, you could close the airvent up or down depending on how hot you want it (and you would have to use a little metal tool to open it by now, or it would melt your fingerprints off!).
Overnight, you would put a lot of coal on top of the ones in there & screw the airvent down till it was nearly closed (banking a fire). This lets it burn really slowly overnight so that it doesn’t run out of fuel. In the morning, you put more coal on and open up the airvent. When it has got going again, use the metal tool on the gizmo at the side that makes the base move. That lets the hot ash drop through to the ash pan underneath. If it is a good burn, the ash will be very fine and white. Don’t drop the ash through first - it take a lot of the heat away with it & opens up the structure of the fire too much.
Coal then was about £15 per hundredweight from the coalman (1992). It was a point of pride to not need a firelighter to start a fire (& you can use dozens of those & still not get it going if you don’t know how to feed the fire & build it properly).
Probably way too much detail…
Oh, Anthracite - I’m never on anyone’s list either - we could start a pity list for the listless (list-less?) ones, but that would be too sad!
Anthracite, you should move to Milwaukee. Lots of old houses with masonry furnaces built right into the basement walls.
[shameless flirting] Then you and I could spend the weekend putting in a stoker, getting covered in coal dust, and… oh, if only if it weren’t for your sexual preference we could have us a time!!
::cries into beer:::[/flirting]
It could nver work out between us - you’re a stoker guy, and I’m a pulverized coal gal (sniff).
[bad joke]Is that a ram-feed stoker you have there, or are you just happy to see me?[/bad joke]
And I won’t even bring up the “screw-fed stoker”…
This is a little off-subject, but I was wondering if Anthracite, or anyone else on this thread, has read the book “Rose” by Martin Cruz Smith? It’s about a 19th century coal mining town and I liked it quite a bit. It has a lot of information about coal mining at the time.
The reason I bring it up is because of one vignette from the book. The protagonist is invited to dinner at the mine owner’s home. The dining room, called the Cannel Room, was made entirely of jet, including the dining room table. The servants each had a bucket of sand in case of fire. Did Smith base this on an actual room or was this a flight of fancy?
I’ve never heard of this book, but I’ll add it to King Coal, by Upton Sinclair, as another book to buy.