Anthracite Quality Vs. Density (Weight Per Unit Volume)?

LehighanthraciteMatt wrote:the sulfur in coal is part volatile part as, they don't account for the overall numbers our sulfur in each sample was 0.5 and 0.47 % but that number fits into part volatile material part as. one of those samples was independent from Cardan Laboratories, not on site....

Oh,ok.We'll let that go.Bottom line remains,higher vol anthracites from the western end and even middle of the field coals will yield more BTUs than equal ash high carbon coal like yours.You will always have a better met coal,but not a better heat coal ,with ash remaining the same.This would make western coals easier to light,and less likely to cause out-fires in the shoulder seasons and summer.Just the facts.Lehigh makes a fine product,that is not in question.

I would imagine that the carbon tertiary structures would come into play in respect to density of the actual material (not bulk density) ? I am more familiar with carbon black structures [ http://www.asahicarbon.co.jp/global_site/product/cb/characteristic.html ] than coal.

http://www.chemistryexplained.com/Ce-Co/Coal.html

lsayre wrote:
Short version: If you have some really light weighing yet full anthracite coal pails, all else being equal, you just might have some great anthracite there!!!

Does this sound right?

There can be significant difference in the volume. Taking a rough guess I've seen it on truckload where there might be up to about 15 cubic foot difference over a a 5 ton load. Also keep in mind the size of the coal effects volume but what I'm talking about here is same sized coal.

The higher density coal is also lower ash, typically you might be in 11% range for most coal but the higher density coal might 5 or 6 percent. You might be saying to yourself that's what I want but if you have a stoker it can be problematic especially if you don't have enough adjustments on it. You need to slow the feed rate and increase the air.

I was delivering coal like that for the entire summer and fall once and when it got into late November I started getting complaints from some people with stokers. Try explaining to a customer the reason there coal won't burn is because it's too good. People with handd fired stoves on the other hand were spoiled, they loved it.

Richard, just to fully clarify, in your direct experience was the fluffier (lighter, less dense) coal generally considered best overall for stokers? And the stuffier (heavier, more dense) coal best for hand fed? Or was it the other way around?

Alaska stoker stoves are handy capped with one setting that you can control, feed rate. so I kinda makes sense back in my stoker days with blashak Id get more un burnt coal or un burnt coal in the center if I was to break a piece of burnt rice apart. On the other hand kimmle rice gave me a better complete burn. Funny how when you think about it un burnt coal is better quality not poor.

Now with a hand fed time is on your side, feed rate is the unchanged variable. You have all the air/draft controls doing your work for you. all you have to do is adjust for the coal carbin content.

Some background reading

Coal density

lsayre wrote:Richard, just to fully clarify, in your direct experience was the fluffier (lighter, less dense) coal generally considered best overall for stokers? And the stuffier (heavier, more dense) coal best for hand fed?

Correct but if you have feed rate adjustment on the stoker you should be able to dial it in. In my own experience I only have the air adjustment on the Van Wert and opening that thing up as far as I do to burn dense coal can't be very efficient. The last time I ended up with coal like that I was going to change the pulley and definitely will the next time.

Richard S. wrote:Correct but if you have feed rate adjustment on the stoker you should be able to dial it in. In my own experience I only have the air adjustment on the Van Wert and opening that thing up as far as I do to burn dense coal can't be very efficient. The last time I ended up with coal like that I was going to change the pulley and definitely will the next time.

Thanks Richard! AHS Coal Guns don't offer much if any adjusting to be done. There isn't any adjustment I can think of on a Coal Gun that would modify the air intake. There is also no feed rate adjustment. It gravity feeds like a hopper equipped hand fed. It stokes via mechanical ashing. All I know to date is that Harmony and Blaschak have worked well for me, and Stockton was problematic. Those are the only coals I've ever purchased and used.

Of these three, Harmony was the lightest in my pails, Stockton was the heaviest, and Blaschak falls about right in the middle of these two. A typical 5 gallon plastic pail average weight breakdown for pea size in my pails would be:

Harmony, 38 lbs.
Blaschak, 40 lbs.
Stockton, 42 lbs.

No air adjustment on AHS and Axemans, they run flat out or in a coma. No in between for the beast.

coaledsweat wrote:No air adjustment on AHS and Axemans, they run flat out or in a coma. No in between for the beast.

And if the beast likes the coal, it will run winter and summer without issues. It's all up to the coal.