Ash Disposal

I am contemplating an efm stoker boiler installation but I live in a suburban area. I am curious if 5-10% ash is the usual amount produced from burning rice anthracite and what I should do with the ashes. I have no place on my property to dump them. The local landfill won't accept them unless they are clear bagged (at $1.25 per bag). The local concrete plant only wants ash if the chemical analysis is certified. Who else would take them at low or no cost?

Mike

In a testing enviroment 8 to 10 % is normal. But in reality it differs. Stokers never burn as well as a had fired stove for one. As pointed out in a few other threads I've burned coal from the very same batch in a stoker and a hand fired unit. As it normally is the stoker ash was chunky for lack of a better term and the hand fired ash was powder...

Although the weight may drastically change the same is not true of the volume. Rough guesstimate is about half of what you put in is going to remain. This can be crushed down to a very small volume but I have no idea how you could accomplish that or where you would get a bag capable of holding the weight.

The borough collects the ashes where I live as the do in some surrounding communities. If that service is not available they pay the garbage man which is usually a nominal yearly fee.

I am aware that hand firing will be more efficient than a stoker but I was not aware that stoker boiler efficiencies would be on the order of 50%.

The fuel cost calculator at hearth.com has a table of likely efficiencies for various fuels and burn methods with modern stokers listed at 70-85% and older boilers in the range of 60-75%. Axeman-Anderson's Anthratube boiler boasts an efficiency of 75% in their online literature. They claim that from 2000lbs of anthracite, 1500lbs will produce heat while 300lbs will be ash and the rest (200lbs) goes out the flue as waste heat. They imply that the efficiencies for other makers of boilers is on the order of 45-50%.

After talking with a sales contact at that firm today, I realized that their design, while very sound, is at least 25 years old. The best coal could do for efficiency would theoretically be total burning down to its ash content or about 87% to 91% from information found online. Since we know that stokers are less efficient than hand firing, we could assume this efficiency to be lower in practice, as you stated. But, is it likely that the AAA achieves 75% with an ash content of 15%.

Anyone out there have one?

As for the ashes, I have found a clean fill pit that I can dump them in without charge.

NEPAForum Admin wrote:Although the weight may drastically change the same is not true of the volume. Rough guesstimate is about half of what you put in is going to remain.

You are misinterpreting what I'm saying. I'm not referring to the efficiency of the coal but the volume of ash compared to the volume of coal that you put in. If you put a 40lb bag of coal through a stoker you can expect to fill that bag up half way with ash. It's not going to weigh 20 pounds but it's still going to be half full.

Thanks. I get it now.

And again that is just rough estimate, I never actually sat down and figured it out. I'm just trying to give you an idea of how much as you are going to generate.