Block Size Anthracite?

I built my own boiler with a 12 cubic ft fire box. Can I get anthracite coal in block size chunks? Any one know?

Stove coal comes in some seriously big chunks, I don't think you would want anything bigger as it would be difficult to shovel. I have a few monster pieces left over from when I burned some two years ago. The larger pieces are about the size of a standard brick.
We are going to need pics of your beast!

http://mysite.verizon.net/vzew10av/

Look around here. Plenty of pics. Brick size might work. Thinking of comeing to PA this week or next to buy three stoves. Any where I can get these brick or block size chunks?

You don't want big chuncks of coal, unless a smaller size would fall through the gaps in your grates. Take a look at the 'pictures of your stove' thread, you can see some photos of my custom made boiler. I made it for wood/coal, hand fed. I converted it to Stoker feed.

For awhile I was burning a mix of stove size and nut size anthracite. I wished it was all nut after I had burnt it for a week or two. The Nut burned longer and better. Even with my huge firebox, it could hold close to 200# of coal. I still had a hard time controling the stove size coal's burn rate to get a 12 hour burn. Any larger size will be a problem.

I'd recommend stove and nut. Use the stove for really cold weather, cover it with a layer of nut to slow the burn rate down for a longer burn time. A layer of Pea over the top of that would make for a 16 hour burn in my stove, but I only had a little pea-sized coal, so I wasn't able to use this proceedure very often.

The use of a stoker feed ended all the duration of burn problems.. Only my ashpan size was a limitation.

Greg L

Also note that stove is more expensive than nut. Last I checked it was about 10% more.

If you go with the stove, you better have a REAL coal shovel.

Pin stripped hat is optional.

LsFarm wrote:You don't want big chuncks of coal, unless a smaller size would fall through the gaps in your grates. Take a look at the 'pictures of your stove' thread, you can see some photos of my custom made boiler. I made it for wood/coal, hand fed. I converted it to Stoker feed.

For awhile I was burning a mix of stove size and nut size anthracite. I wished it was all nut after I had burnt it for a week or two. The Nut burned longer and better. Even with my huge firebox, it could hold close to 200# of coal. I still had a hard time controling the stove size coal's burn rate to get a 12 hour burn. Any larger size will be a problem.

I'd recommend stove and nut. Use the stove for really cold weather, cover it with a layer of nut to slow the burn rate down for a longer burn time. A layer of Pea over the top of that would make for a 16 hour burn in my stove, but I only had a little pea-sized coal, so I wasn't able to use this proceedure very often.

The use of a stoker feed ended all the duration of burn problems.. Only my ashpan size was a limitation.

Greg L

I am getting a ten to twelve hr burn time with wood. My fire box is 12 cubic feet. I would think the little stuff would burn up to fast. I found a place to buy some brick size. I was hoping to get the burn time up to 20hrs. Do you have any pics you could post or e mail? I was thinking of mounting a 175 cfm blower fan shooting into the coal pile on some sort of timer to blow the ash away. What do you think? I think they melt steel like that. I will have to be careful.

Take a look at the shape of a sucessfull firebox. In say a Harman Mark III, or a similar hand fed stove. The shape of a good firebox is vertical sides, shaker grate for the entire floor and as deep as possible. The square footage of a coal fire determines the heat output, the depth or cubic capacity determines the duration of burn. Coal must have air only from the bottom, and you control the heat and duration of burn by the amount of air going through the coal bed.

A coal bed of stove coal has much larger passageways between the large hunks of coal, smaller passageways between the smaller nut coal, and smaller yet through pea coal. The more you restrict the air passageways the longer the burntime. It's not the size of the hunks of coal. It's the volume of air getting through the coal bed. It is a common practice to cover a bed of coal with a layer of smaller coal to extend the burn time.

Burning coal is not at all like burning wood. Coal must be in corrrect firebox to burn well, not get clinkers and not ash up the grates... I've been through the entire agonizing process and learning curve.. and I converted to a stoker feed for my old boiler. My firebox was just too much a wood burning firebox and not close enough to a coal firebox to work well.

Like I said, as long as the nut and stove coal won't fall through your grates, I'd stick with these two sizes.. they are what work. As for blowing the ash off the fire, I can't imagine it working. A coal fire has the majority of the ash at the bottom of the fire, the fire burns from the bottom up. this is why a deep fire works so well. Have a deep fire, shake the ashes out from the bottom using the shaker grates, collect them in the ashpan below, add fresh coal to build the coal bed depth again and close 'er up. Messing with a coal fire usually results in a fire going out, or clinker formation.

Hope this helps.
Greg

I am learning something. Currently I have a 36x48inch wide and long fire box x almost 4 ft high. 8in high my grate sits. So I have plenty of air from under the fire. I control this by placing fire brick in front of of the air intake. With wood I have to cut the air down to almost nothing. Sounds like I will have sufficient air under a coal fire. My grate is 1in steel rebar. With 6inx6in holes. Or every six inches a rebar goes across the box. Small coal would fall through. Brick size with putting stove size on the top should work. What is clinking? and it sounds like I will have to manually shake this great or make something that will do it for me to drop the ash. Correct? How often will it need shaken? Thanks for your time. Nothing like re iventing the wheel. Need any heat and AC advice. Let me know.

You will need to reconfigure the shaker grates, a 6" hole isn't going to work, even with stove coal.

There's a grate system that's designed to be used with multiple fuels. Trademarked as Rolla-Grate, it's now manufactured by AHS. It's part of their multi-fuel boilers, but looks like it could serve as a base to any boiler. Give them a call and see if the sell it individually. The Rolla-Grate is an interesting design because you can rotate each grate individually if desired. This would allow shaking down selected areas of a coal fire. Or perhaps by rotating an individual grate(s) closed reducing the size of a burn.

See: http://www.alternateheatingsystems.com/Multi-Fuel ... oilers.htm

What kind of metal are these grates made out of? I have had trouble with my 1 inch rebar turning cherry red and bending under the weight of the wood. One poster said coal could get to 4000 degrees. Do you think it gets this hot in a boiler? or more like 2000 degrees?

Grates are usually made of cast iron. They can be exposed to a lot of heat, esp. just after shaking when the hot coals may come in contact with them. But since a coal fire drafts air from underneath , the air has a cooling effect on the grates as well.

You may want to look at watercooled grates, that monster may need them.

I had thought to use 1 in SS bar but who wants to pay 500 bucks. The 1in steel rebar was a few hundred. I am going to PA mon to check out some stoves. I'll get some brick and stove size coal and give it a shot. We will see what happens.