Smithing coal vs. fuel coal for power plants.

[herchammer]

I was wondering what the difference is between these two types of coal. I would assume, that coal used in power plant boilers, has more impurities than smithing coal. Anyone have any thoughts?

[John B]

Why assume that? More 'impurities', more clinker?

[Doug C]

Coal is either anthracite, bituminous or lignus. Quality is in that order with anthracite typically being the best quality.

"Blacksmithing" coal as we talk about it here is a bituminous (soft) coal that should be low in impurities (carbonate, phosphorus and sulfur) and high in its abilities to coke (plasticity). It tends to burn faster than anthracite coal and stays lit longer when no air is being applied.

Power plants also look for coal that is low in volitiles like ash, carbonate and sulfur as it produces less slag. I am assuming that they probably use Anthracite coal.

[John B]

Is power plants slag blacksmiths clinker?

[Sask Mark]

From what I understand the coal used in powerplants in my area isn't suitable for smithing. It doesn't generate much heat (low btu) and it generates quite a bit of ash.

The powerplants use it because it is all that is available locally.

[parker]

i have a reletive that works at a plant. so i thought i had it made for getting coal. he told me that the coal they use wont even light with a cutting torch. they crush into powder and basicly spray it into the buner. the btus are very very low campared to blacksmith ccaol

[CurlyGeorge]

I got a 100 pound bag of ILLINOIS coal, one time, for $5.00. I burned up that bag in less than half the time of the 50 pound bags of Pocahantus coal that I normally use. I think that it was "power plant coal". It gave me more smoke and ash. I was able to forge weld with it, but, it didn't work nearly as well as my normal coal. :)

[ThomasPowers]

Bad assumption; I don't know of any anthracite burning power plants. Bituminous and even in some locations lignite is used. Power plant coal is often fairly poor in quality and generally produced by strip mining.

[free2forge]

I can see that there is a lot of misinformed info in this area. I live and work in coal minning area. all of the coal that goes into the 3 major plants in our area comes from several diffrent mines (all underground) the plants have several stockpiles of diffrent coal and blend them depending on their burn rate so they can keep a uniform fire. all the mines around here and the states around us are bituminous, alot of the impurities not all but alot of them come from the way the coal is mined. I am short on time right now but would like to hash this around a bit more later

[Harri]

I have used Power plant coal for a couple of years. It is as good as can be ; low sulphur and almost no slag or clinker.

[John B]

That's probably because of the countries location ref. the coal available and the type of heating generation used within the power stations, and their conversion efficiency plus other considerations like emission controls etc.

[HWooldridge]

Some years ago, I was able to get several buckets from one of our local plants but it turned out to be a form of lignite - had low BTU's and no coking characteristics. OTOH, a buddy of mine picked up a few tons of coal after a train derailment in North Texas that was destined for power plants and it was great stuff. A lot depends on what the individual plant is set up to use in their furnace so you just have to try a sample if available in your area.

[Ten Hammers]

We have coal trains come through Ottumwa Iowa. THis coal is junk for forging. As noted, the coal is ground to a powder and injected (with some LP )into the burn chamber. I was invited to observe this a few years ago but never got to make that trip. OTOH, I have been told that some plants back east use Sewell seam coal for their energy. We should be so lucky here.

[matto]

most all blacksmith coal is bituminous (hard coal) very little ash and moisture content high btu out put. power plants use lignite (brown coal) it has very high moisture and ash content. power plants also use sub bituminous a little less ash and moisture than
lignite. anthracite has the highest carbon content almost no moisture or ash contentan great btus. only thing is it is hard to get and is costly, it is also the closest to coke.

if you want all the tech stuff on it Dr leroy jacobs has written many articals on coal.
mark aspry's book and the rocky mountain smiths forge facts have some of the articals.

[matto]

one other major factor is that power plant coal does not have a good coking ability.
were blacksmith coal does.

[Doug C]

So where is anthracite used? Do Power plants just use what is mined locally? If the are always using low quality, lignus, coal doesn't that seem very inefficient? Just curious about how reality varies from what I have read.

[matto]

as far as i know there is not much anthracite used. to hard to get. like most blacksmith coals (metallurgical coal) comes from under ground mines. as for most power plant coals come from strip mines (wyoming). power plants do mix different coals together but bottom line is when you go through 110 rail cars a day at 100 tons per car. you are going to look for and use the stuff you can get the cheapest and fastest. ($12 to $20 per ton (fob: freight on board) from the mine)

[fat pete]

anthracite was what we used to heat the house...its hard coal...shiny and not quite as dusty as bituminous... soft coal..we in PA have lots of anthracite....used to be used in trains also....there is a mine north of me under a town called Centralia that has been burning for 30-40 yrs the town has moved and it looks like volcanic waste land...hard coal burning for a long time...once u get anthracite lit it goes and goes and in the morning it goes out...the trick was to get the draft to work right and the anthracite would glow for ever...it does not coke like smithin coal...nor smell like it...u can smith with it albeit realy tuff to ignite

[fat pete]

Types of CoalTypes of Coal

Types of Coal
We use the term "coal" to describe a variety of fossilized plant materials, but no two coals are exactly alike. Heating value, ash melting temperature, sulfur and other impurities, mechanical strength, and many other chemical and physical properties must be considered when matching specific coals to a particular application.

Coal is classified into four general categories, or "ranks." They range from lignite through subbituminous and bituminous to anthracite, reflecting the progressive response of individual deposits of coal to increasing heat and pressure. The carbon content of coal supplies most of its heating value, but other factors also influence the amount of energy it contains per unit of weight. (The amount of energy in coal is expressed in British thermal units per pound. A BTU is the amount of heat required to raise the temperature of one pound of water one degree Fahrenheit.)

About 90 percent of the coal in this country falls in the bituminous and subbituminous categories, which rank below anthracite and, for the most part, contain less energy per unit of weight. Bituminous coal predominates in the Eastern and Mid-continent coal fields, while subbituminous coal is generally found in the Western states and Alaska.

Lignite ranks the lowest and is the youngest of the coals. Most lignite is mined in Texas, but large deposits also are found in Montana, North Dakota, and some Gulf Coast states.

Anthracite
Anthracite is coal with the highest carbon content, between 86 and 98 percent, and a heat value of nearly 15,000 BTUs-per-pound. Most frequently associated with home heating, anthracite is a very small segment of the U.S. coal market. There are 7.3 billion tons of anthracite reserves in the United States, found mostly in 11 northeastern counties in Pennsylvania.

Bituminous
The most plentiful form of coal in the United States, bituminous coal is used primarily to generate electricity and make coke for the steel industry. The fastest growing market for coal, though still a small one, is supplying heat for industrial processes. Bituminous coal has a carbon content ranging from 45 to 86 percent carbon and a heat value of 10,500 to 15,500 BTUs-per-pound.

Subbituminous
Ranking below bituminous is subbituminous coal with 35-45 percent carbon content and a heat value between 8,300 and 13,000 BTUs-per-pound. Reserves are located mainly in a half-dozen Western states and Alaska. Although its heat value is lower, this coal generally has a lower sulfur content than other types, which makes it attractive for use because it is cleaner burning.

Lignite
Lignite is a geologically young coal which has the lowest carbon content, 25-35 percent, and a heat value ranging between 4,000 and 8,300 BTUs-per-pound. Sometimes called brown coal, it is mainly used for electric power generation.

[herchammer]

So, what I'm taking from this thread, so far, is that I should just try a sample before I commit to a large quantity. Quite a lot of information, although, I'm not surprised. That's why I asked the question on this forum. As always, thank you all so much for sharing what you know.