Run of Mine Coal, What Should I Do to It?

First, thanks to ktmrider for showing me this site.

Now a quick history. I have an owb and it was suggested to me to use coal to supplement my wood consumption. Talking with the locals, Central Pa, I got in touch with a guy who delivers 'run of mine' coal.

Being a newbie burning coal, I trust his suggestion and bought 5 ton. It is pitch black, little/if any visible rocks and is a mixture of softball size pieces down to sand with little/no airborne dust. Looking around on the site I see that some sift and seperate the coal. The guy I bought it off of says just to shovel it in as is, maybe wet it down prior to putting it in as the dust acts like gas and will make a fireball.

My question to the forum....Should I invest a weekend and sift it? Or should I just shovel away?

My local prices are $55/ton p/u or $75 delivered FYI.

Great site too, many thanks.

s

Just shovel it in, you'll just make a big mess sifting it. I would pick the rocks out, they will only cause trouble as they accumulate on the grate. You may have to play with the draft and/or supply overfire draft air.

Hello Stipton, welcome to the forum. When I was burning Bituminous with wood, I'd get a hot bed of wood coals, add logs or splits down each side of the firebox, leaving a gap or 'V' in the middle. Then I'd fill the gap with coal.

It will smoke like crazy at first, the flames from the wood will help burn off some of the smoke, you will want to add some air to the fire to help too.

Once the fire has burn off the smoke, you should see a big center pile of coal glowing with some flame. Sometimes the coal will get soft, gooey and stick together into one lump. You can break up this lump to increase the burn rate and heat output. The fine sand-like coal will stick together, so plan on breaking this up. I used a garden hoe or similar tool.

Just make sure you add coal only to an established hot fire, 'cause coal doesn't start well like wood.

Hope this helps, Greg L

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Great advice, thanks!

Looking at some of the pictures on this site of burning in action, I get excited because I love cheap heat! Compared to a tri-axle load of hardwoods at $500 and labor, time, gas and wear and tear on the Husky to 5 ton of bit coal at $375, just shovel it in, I think coal will make this winter much easier than last.

I feel I have a good quality owb as the box does have a 'v' shape, flowing down towards the shaker grates.

Thanks again for the tips and I will keep my eye on this site for more info in the future.

S

Since you have shaker grates, you probably have air feed to the underside of the grates as well??? This will be your primary air source, above the fire air, probably through a vent in the door would be your secondary air.

Use primary air for the long burn, add secondary air when a fresh load of coal is added, this will help burn off the initial smoke and soot. Once burn off, reduce the secondary air and feed only primary under the fire air to the coal.

Keep a bed of hot coal going, and you can just keep adding coal. You will probably have to shovel out clinkers ocasionally, like once a week in really cold weather,

a clinker is the ash from the coal all stuck together. The ash in Bituminous coal will stick together at regular burn temperatures, so the 'V' shaped firebrick and bottom grate will tend to funnel the hot ash down to the grate and force the ash together, or compress it. This causes the ash to stick together. Most of the time the shaker grate will break up the clinker, but sometimes you may have to rake it out or burn the fire down, and shovel it out. Then start a wood fire again to get the coal going.

I had to shut my boiler down weekly when burning just bituminous, but otherwise the coal burnt well,

Hope this helps. Greg L.

That is correct LsFarm. My air supply is under the shaker and I can adjust the amount of air the blower pushes in. Right now with wood, I keep the gap at about 1/4 to 1/2", about an 8" circular opening with a metal disc that regualtes the air. I think I will open it up to about 1"+ for starters to see how it flows.

My biggest question is the amount of coal to use, like how big of a pile should be in the fire box. With wood, I fill every nook and cranny up to the top. I'm thinking that a nice 5 gallon bucket full will do it, after I establish the start up ash bed and wood coals. Heck, give me a week and I will have it down.

I will take a couple of pics this evening of the firebox and setup for reference and post them here.

Is that your farm in your avatar pic? Nice looking chunk of land. Thanks again for the tips.

S

You haven't seen his latest pic? It looks like he found a seam of coal in the backyard.

Stipton,

Glad to see you made it over to this forum. Most of the members here burn anthracite coal which is a whole different animal than bituminous coal. There are a few bit coal burners however, myself included. I would also suggest just shoveling it in. No need to sift it, but the rocks might be a problem. rocks are not good, they don't like to burn too well.
I always like to "Bank" the coal on one side of the boiler wall to allow it to burn alot better. You will most likely discover an annoying problem called "bridging" that is when the coal seems to be burning on the bottom but the top has a crust on the top that sort of insulates the coal fire and keeps it from throwing alot of heat. banking the coal on one side of the boiler will help with this. I have a few other tricks to combat bridging that might help you out later...

BTW, does your OWB have a aquastat on it? pressure relief vavle or is it non pressurized? will it completely shut off all combustion air once the water is up to a preset temp? The reason I ask is that once coal gets going it REALLY gets going and I had one indicent where my blower malfunctioned and was allowing just a tiny bit of air into the fire. My water temp was up to 300 deg !! This obviously is not good.

Hello ktm, so far so good. Lots of good info, thanks.

I have read some stories over on the other forum, I can see where coal could really make it worse. I do have an open system and just worry about keeping the water properly treated. The only air that goes in is from the blower and it shuts off at a preset temp.
Great idea on banking the coal. I can see how that would keep the pile self cleaning. I can feel the heat coming off the radiators now...

I took some pics of my firebox so I can pick LsFarm's brain for some possible fire brick suggestions. Funny thing is I have a friend who just so happens to own a ceramic factory and he specializes in custom industrial pieces for furnaces, jewelers and scientific mumbo jumbo. He can pretty much make any size of anything with the material. He even asked for the company I bought mine from to see if they would be interested. They declined due to just burning with wood would not get hot enough and 'gum up' the ceramics and not burn efficiently. I do think some kind of brick on the sides may help though. Its on the 2 year plan, maybe 3ish.

Looks like 3 pics to a post...thanks all.

S

Couple of coal pics. Some nice big chunks. I never thought 5 tons would be so much. I hope it lasts a loooong time.

S

Ok, just one....upload problems.

Stipton,
Yep, you might want to get some firebrick in there. I bought some new ones last year at the local concrete company. They cut them to size right on the spot. they were only a buck or so per brick.

As far as your coal, I will tell you that the very fine sandy stuff ( AKA Fines) will not burn too well, it will bridge really bad and is just tough to keep it from doing so. I usually by nut coal. it is about the size of a quarter or 50 cent piece and it allows the air to come up through the coal fire alot better than the really fine stuff. That really cuts down on the bridging if you can keep the air coming up through the chunks of coal.

Stipton, what I did when I had lots of fines to burn, was to put a shovel-full or two in a paper bag, roll it up like a log and add to a log fire, the bag burnt away, the heat fused the fines into a 'coal-log' which would usually not fall apart and smother the fire. The loose fines act like a blanket and like KTM said, won't let air through, which smothers a coal fire. Wood can burn with air from the top and sides, coal won't burn unless the air comes in from underneath.

As for firebrick, it doesn't look like you have much room on the sides for brick, the rocking grates cover most of the bottom. You may be able to stand the thin brick, 1" or so thick brick on the edge and not interfere with the rocking action of the grates.

Grab a measuring tape and measure the length and width of the firebox, and measure from the side of the box to the edge of the grates when the grates are opened up, I think you will need at least 1.5" to clear a row of brick.

This firebox will probably do a good job burning Bit. coal if burnt on top of a wood fire, but may be a challenge with lots of fines , bridging and clinkers.. Time will tell, depends on your coal. You'll get an education for a few weeks at first, then another education when the weather turns real cold and you have to burn hotter and longer.

Take care, Greg L

I would start by burning the chunks until you get a feel for how the fire reacts. Once you have learned what the stove wants you can work down to the smaller stuff without too much aggravation. The bag trick sounds clever, I would have thought the powder would be big trouble.

I think you are going to want a much taller stove pipe burning bituminous.

You guys are gonna make me an expert. That will impress my wife. You should see it when I fire her up coaledsweat, makes a hel-of-a mess. Kidding, that's for the summer to keep the rain out, I use a stack, maybe do a double this year...

I will look into some thin brick(s) that I can potentially line the sides with. The slope is inclined enought that I should not need any bracket or welding to secure the brick. You are right, I think I may have an 1' or so of width on the lip at the bottom near the grates that it can sit on. Excellent, a weekend project...I will review your firebox/bricks pics again.

Many thanks for all your help for the rookie.

S

At the brickyard, tell them you want "splits". They are about an 1 1/4" thick, about half the width of standard firebrick.