Sciencemadness Discussion Board - Free coal ash

Free coal ash

Morgan - 22-3-2014 at 17:57

I thought this was questionable.
"Bingo. Coal burning power plants in the Midwest give away an estimated quarter-million tons of coal ash every year. That’s at least three times the size of the big spill in North Carolina. And for that spill, Duke Energy is facing a billion-dollar cleanup tab. While instead in the Midwest, you haul the coal ash away and you spill it for free."
http://www.loe.org/shows/segments.html?programID=14-P13-0001...

Etaoin Shrdlu - 23-3-2014 at 11:32

So what's your take on this?

Mine is that governments spread bottom ash on roads, which is pretty well locked into a hard matrix, and generally has heavy metal levels not much higher than the surrounding soil. Duke Energy pumped an estimated 99,000 tons of unfiltered particulate matter, in addition to water which had been leaching chemicals from ten times that amount of waste, out of their toxic holding ponds directly into one river. That would have been a problem even if it was ordinary soil. These are two very different scenarios.

Morgan - 23-3-2014 at 18:54

A few tidbits I dug up in my quest to learn more.
What is coal ash and how can it be used?
https://www.youtube.com/watch?v=rKlJElb2Be0

Coal Ash: 130 Million Tons of Waste
https://www.youtube.com/watch?v=1PYexB76KIQ

Fantasma4500 - 23-3-2014 at 23:16

imagine how much acetone that could be made into if the CaCO3 in the ash would be used to make calcium acetate then followed by dry destillation..

phlogiston - 24-3-2014 at 02:29

Why imagine if you are a nerd?
Ash = approx 40% calcium carbonate. Yield of reaction about 83%

0.25*106 tonnes ash --> 0.1*106 tonnes CaCO3 = 632*106 moles --> 524*106 moles acetone --> 30461 tonnes of aceton, or about 38500000 liters

Or about enough to fill my towns swimming pool 12 times over.

The same amount of coal ash also contains about 1.25 gram of radium. A well functioning nuclear plant releases less radiactive isotopes in the environment than a coal plant.

[Edited on 24-3-2014 by phlogiston]

forgottenpassword - 24-3-2014 at 04:31

I'm sure it wouldn't be economical to convert it into acetone.

Morgan - 24-3-2014 at 13:12

I was trying to get a feel for what they do with coal ash and can list a few items now. For the home it is used in roofing shingles, cement, carpeting, countertops, wallboard, paint, and bowling balls. And for roads, embankments, as well as an additive to crop soils.

Nebraska has an unusual use for coal ash.
"On an infrequent basis, the Nebraska Emergency Management Agency (NEMA) has applied limited amounts of coal bottom ash to portions of the Platte River in late winter. The purpose of the applications is to promote gradual melting and prevent ice jams and flooding."
"Analysis of the bottom ash used in this process indicates that the material is mostly carbon, with what is determined to be an insignificant amount of metals and other constituents."
http://www.deq.state.ne.us/Publica.nsf/pages/11-008

Location, location, location ...

"For months, train cars lined up to be loaded with sludge dredged from the river. The sludge was then carted down to Uniontown, Alabama, a mostly poor, mostly black county, where an enterprising commissioner decided that taking the waste was an economic opportunity. The county ended up taking about 4 million tons of it and dumped it in a landfill—for the price of just $4 million."
"It is not unusual that a place like Uniontown ended up with the Kingston waste: Coal ash is almost always dumped in communities that don’t have the political or financial muscle to reject becoming other communities’ trashcans. According to a 2012 report, of the nearly six million Americans who live within three miles of a coal-fired power plant, 39 percent are minority, and the average per capita income is $18,400."
http://freethoughtblogs.com/pharyngula/2014/03/22/potential-...

Exterior trim.
http://www.boralamerica.com/Trim/About/boral-truexterior%C2%...
https://www.youtube.com/watch?v=6jucf__occE

[Edited on 24-3-2014 by Morgan]

roXefeller - 26-3-2014 at 13:23

Quote: Originally posted by forgottenpassword

I'm sure it wouldn't be economical to convert it into acetone.

Even if it was economical to convert to acetone, it is the remaining portions of these reclamation works that make it uneconomical. Phosphorus mines for example have loads of mineral rich tailings, but because they have elevated amounts of radium and whatnot, the tailings become a tarbaby. If you take them from the mining company for your use you then need to find someone dumber than you to take what remains because of the cost associated with legal disposal. The process for uranium mining (which has terrible tailings consisting of decay products) is trying to move towards in situ mining, where the uranium commodity is the only thing to come up from the ground and the tailings stay below in the seam.

Steam - 26-3-2014 at 14:44

Quote: Originally posted by roXefeller

Quote: Originally posted by forgottenpassword

I'm sure it wouldn't be economical to convert it into acetone.

Very true, I used to live in Florida where they would have huge mounds of slightly radioactive dirt left over from the phosphorus mines. These mounds cost millions to maintain and took up thousands of acres of land. It seams silly to me why they cant push it back into the ground for that's where it came from originally!

phlogiston - 27-3-2014 at 04:56

Although it may technically be doable it may turn out to be a far more expensive solution.

Morgan - 27-3-2014 at 13:14

Quote: Originally posted by Steam

Quote: Originally posted by roXefeller

Quote: Originally posted by forgottenpassword

I'm sure it wouldn't be economical to convert it into acetone.

You've also got fluoride pollution to contend with in the phosphate industry. In some ways it reminds me of the coal ash scenario, where we will sprinkle coal ash on icy roads or as with Nebraska, sprinkle it on ice jams in the Platte River, anything to get rid of a pollutant or something many would prefer not to have in their own backyard.

"Thus, while US industry continues to satisfy its growing demand for high-grade fluoride chemicals by importing calcium fluoride from abroad (primarily from Mexico, China, and South Africa), the phosphate industry continues dumping large volumes of fluoride into the acidic wastewater ponds that lie at the top of the mountainous waste piles which surround the industry."

"Of course, not all of the phosphate industry’s fluoride waste is disposed of in the ponds. As noted earlier, the phosphate industry has found at least one regular consumer of its silicofluorides: municipal water-treatment facilities. According to recent estimates, the phosphate industry sells approximately 200,000 tons of silicofluorides (hydrofluorosilicic acid & sodium silicofluoride) to US communities each year for use as a water fluoridation agent (Coplan & Masters 2001)."

"Another EPA official, Dr. J. William Hirzy, the current Senior Vice-President of EPA Headquarters Union, recently expressed a different view on the matter. According to Hirzy:"
“If this stuff gets out into the air, it’s a pollutant; if it gets into the river, it’s a pollutant; if it gets into the lake it’s a pollutant; but if it goes right into your drinking water system, it’s not a pollutant. That’s amazing… There’s got to be a better way to manage this stuff.”

https://www.youtube.com/watch?v=ViNNIwmzTzI#t=24m56s

kecskesajt - 12-12-2014 at 03:49

Also it can be used to for cleaning.The ash contains Na2CO3,K2CO3 wich is used as washing soda/potash.And neutralise some nitrated shits.

unionised - 12-12-2014 at 13:40

Quote: Originally posted by Antiswat

imagine how much acetone that could be made into if the CaCO3 in the ash would be used to make calcium acetate then followed by dry destillation..

I may be mistaken, but I think that the answer in principle is
"exactly as much as you can make with a teaspoonful".

Because I can take that spoonful, add acetic acid, pyrolyse it to get the acetone, heat the resulting "ash" in air and reform calcium carbonate which I can react with acetic acid...
and so on.
If you want to be petty, I can even recycle the CO2 liberated from the dissolution, to make the pyrolysed calcium compounds back into the carbonate.
Since you can recycle the calcium carbonate indefinitely, there's no (theoretical) limit to how much acetone you could make.
You are likely to run out of vinegar first.

Amos - 12-12-2014 at 15:04

40% calcium carbonate might fly for wood ash, but coal ash contains much less. There's much more silica and alumina in there, which is disappointing.

subsecret - 12-12-2014 at 16:08

Spreading it under asphalt roads would be a good idea, as they already paint the lines with lead chromate/carbonate. The ash could also be crushed and added to concrete, possibly to replace the sand in the mixture.