The other toxic energy spill

June 17, 2010 5:20 AM

Coal Ash: the other energy spill. A five-part investigative series from the Institute for Southern Studies about the toxic residue left after coal is burned.
1. Coal's Dirty Secret Coal ash is "the second-largest industrial waste stream in the U.S." but is not regulated by the federal government
2. Disaster in East Tennessee Effects of the December 2008 rupture of a dike releasing "a billion gallons of muddy, gray coal ash loaded with arsenic, lead and other contaminants" are still being felt
3. Power Politics Coal ash was given a special exemption from hazardous waste regulation in 1980; attempts since then to tighten the exemption have failed
4. Dumpsites in Disguise Toxic coal ash is increasingly being recycled into building materials and other uses, again largely unregulated
5. What's Next for Coal Ash? The EPA has offered two proposals; one treats coal ash like hazardous waste, the other like "ordinary solid waste."
posted by mediareport (29 comments total)

Coal ash used to be a lot less harmful. It was used in building materials, I think. But (I think) once they started with this "clean coal" stuff all the harmful stuff ended up in the solid ash, instead of the air.
posted by delmoi at 5:53 AM on June 17, 2010

The other toxic energy spill

That hasn't happened. There certainly have been some accidents involving coal ash, but if not for the collection of the ash at the source (resulting from the 1970 Clean Air Act), all of it would have been spilled into the atmosphere. Score one for government regulation here. Burying the ash in a landfill is far from perfect, but it is an improvement over letting it go up the stack.
posted by three blind mice at 6:01 AM on June 17, 2010

So, we can't let it fly up into the air, we can't let it sit on the ground, we can't bury it, we can't recycle it...

WTF do we do with it, then?
posted by hippybear at 6:10 AM on June 17, 2010

For those who haven't heard of it, unlike the burning settler's cabin at Disneyland, there are plenty of long burning fires that they can't cut the fuel source off. Maybe they should mix the old ash with the current fire. Twice the toxicity coming to an aquifer near you! Fantabulous!
posted by LD Feral at 6:11 AM on June 17, 2010

WTF do we do with it, then?.

Ignore the problem just a little bit longer.
posted by symbollocks at 6:21 AM on June 17, 2010

WTF do we do with it, then?

We build a giant machine to rocket it into the future, where we will never have to see it again!

Oh... wait.
posted by GenjiandProust at 6:35 AM on June 17, 2010 [1 favorite]

So, we can't let it fly up into the air,

The operators of power plants no doubt argued that it would be too expensive to do anything but let it fly into the air. But due to government regulation (against the objections of the energy companies), a lot of the ash and sulphur dioxide that causes acid rain is being "scrubbed" from the exhaust of coal-fired plants. We don't talk about acid rain today as we did in the 1970s. That's progress.

we can't let it sit on the ground,

The operators of power plants no doubt argue now that this IS too expensive....
posted by three blind mice at 6:37 AM on June 17, 2010 [1 favorite]

All the talk about clean coal reminds of the ads for cream cheese that touted its having "less calories than butter." Very direct approach: take this single most objectionable attribute of your product and deny it right up front.
posted by StickyCarpet at 6:49 AM on June 17, 2010 [1 favorite]

On the upside, when combined with epoxy, fly ash makes an excellent and inexpensive repair compound.
posted by Tube at 7:07 AM on June 17, 2010

It seems a bit much to regulate ash as a hazardous waste, but on the other hand it seems lax to not at least require it go into a lined landfill.
posted by wierdo at 7:08 AM on June 17, 2010

Point of reference: if sand has blown from a beach or sand dune onto asphalt roads, it is considered toxic waste and must be disposed of as such, at least in California. No link for this, but something I learned at work.
posted by filthy light thief at 7:09 AM on June 17, 2010

filthy light thief wrote: "Point of reference: if sand has blown from a beach or sand dune onto asphalt roads, it is considered toxic waste and must be disposed of as such, at least in California. No link for this, but something I learned at work."

It amazes me I haven't yet developed cancer of the foot. I grew up in Arkansas, I'm sure you can figure out the rest.
posted by wierdo at 7:36 AM on June 17, 2010

Points of reference:

Coal ash is the largest source of mercury in the US. Mercury Hotspots linked to coal plants. USGS1 USGS2

Coal ash is a source of exposure to radiation in the US. Living downwind of a coal plant gets you as much exposure as living down wind of a nucelar plant. Neither are particulalry significant in terms of exposure. Coal Ash is more radioative than nucelar waste. USGS EPA.
posted by bonehead at 8:07 AM on June 17, 2010 [1 favorite]

But (I think) once they started with this "clean coal" stuff all the harmful stuff ended up in the solid ash, instead of the air.

No "I think" about it, delmoi; the first part of the series mentions that point:

And as a consequence of efforts to make burning coal cleaner, new technology to collect airborne coal ash from the smokestacks of power plants has increased the concentration of toxic contaminants in coal ash, heightening its public health and environmental risks.
posted by mediareport at 8:13 AM on June 17, 2010

the burning settler's cabin at Disneyland

The vegetation surrounding that cabin is most likely made from petroleum by-products.
posted by StickyCarpet at 8:21 AM on June 17, 2010

2. Disaster in East Tennessee Effects of the December 2008 rupture of a dike releasing "a billion gallons of muddy, gray coal ash loaded with arsenic, lead and other contaminants" are still being felt

Previously.
posted by homunculus at 8:50 AM on June 17, 2010 [1 favorite]

WTF do we do with it, then?

There is no one answer, but there are lots of ideas.

Before touching on those, consider that the hazardous components left behind are not simply a product of the use of coal for energy, but dependent on the composition of the coal used. Garbage in, garbage out. When the coal is just sitting in the mountain, it's not a problem. When we use the coal for energy, we're taking the sort of structure out of it, and then leaving all this stuff that doesn't produce energy behind, which is the "waste". The composition of the waste depends on the process used to burn the coal, the process used to cool the waste, and like a million other factors that heavy-duty engineers get to figure out. The problem comes in when the process we're using to take this mountain of coal and turn it into energy leaves behind minerals, heavy metals, and other chemicals, that can dissolve in the air, water, soil, etc, and eventually into us in forms that we are not able to process and interfere with our ability to continue to exist. In many cases, they also interfere with other animals and plants.

One suggestion in that case would be to stop putting garbage in, i.e. use only coal sources that are known to have a low concentration of the more toxic compounds. The only known downside to this approach (as far as I can see) is cost. While my belief is that eventually the cost of polluting the environment and creating environmental disasters-in-the-making will exceed the cost of, say, caring about these things and acting responsibly toward the people you serve and the environment you exist in, it seems this is not currently an acknowledged reality amongst the people running the coal plants/utilities/regulators/miners/etc.

The reality is that people are currently running coal power plants, and if we assume that this is going to continue, and if we assume that sources of coal containing toxic materials will continue to be used, we can approach the question of "WTF do we do with it then?". Most of the approaches I've seen that make any sort of sense involve creating a compound that prevents the chemicals from leaching into the soil, air, water, plants and animals. As mentioned in one of the reports, "Some of the reuses for coal ash, such as recycling it into concrete, are not very controversial even among environmental advocates, since they're believed to lock in toxic contaminants."[1] I've seen some pretty positive results from IGCC plants that gasify the coal and produce a "slag", which is sort of a glassy substance that has a stable structure that ideally keeps the "bad stuff" from leaking out.

I am not an expert by any means, but the more I read about this, the more I think maybe we should just not do things this way. That it would be easier to find cleaner and safer, if more expensive, forms of energy and use less of it than try to get the most energy for the lowest price via a complicated and potentially dangerous process. Why not shift the question from "What do we do with this?" to "Why are we making this?".

Here is some reading:
Here's a patent for a process to convert slag to portland cement. As an added bonus, we get to save energy because the slag is already really hot, so we don't have to put as much energy into the already energy-intensive process of making Portland cement.
This college paper on coal-to-methanol does a pretty good job outlining the coal gasification process, wastes, and potential uses.[doc]
Producing Fired Bricks Using Coal Slag From a Gasification Plant in Indiana describes some reduced-quality, but ASTM-approved bricks you can make. This paper is from the "World of Coal Ash Conference. Really.
posted by nTeleKy at 8:55 AM on June 17, 2010 [2 favorites]

my entire hometown is built, financially & (partially) physically, on a coal-burning power plant. taxes generated by the plant keep the town in the black and have financed things like an olympic-sized indoor swimming pool that many cities envy, and part of the town--the two trailer courts they built during the 'boom days' back in the 60s--sits on fly ash graded over with soil. before the trailer courts were built, a swamp ran behind the town, with part of it used as the town dump, and both separated us from the fields of fly ash, which led to the railroad tracks in back, and then pure forest all the way to the top of the hill). we used to play there when we were kids--walking the tracks, throwing rocks at mysterious things in the dump, poking sticks in the swamps to see what we could stir up. some parents were a little picky about letting their kids play at the dump, but what they didn't know didn't hurt them & there sure was some interesting stuff back there especially to a kid?. i remember some of the older kids in town shooting rats at the dump on hot summer nights. my mom told me that she couldn't hang clothes in the yard when they were purging the smoke stacks because the clothes would be black when she went to get them, so she'd end up doing laundry twice. they put in the stack scrubbers thanks to the clean air act 3 blind mice mentioned, but by then everyone was using their clothes dryers.

and i always thought it was breathing the air that was going to kill me.
posted by msconduct at 9:03 AM on June 17, 2010

That it would be easier to find cleaner and safer, if more expensive, forms of energy

Effort and expense are completely interchangeable.
posted by Jpfed at 9:23 AM on June 17, 2010

VA Power and a developer here built a golf course with 1.5M tons of coal ash. It didn't turn out to be the win-win they were hoping for.
posted by gimli at 9:39 AM on June 17, 2010 [1 favorite]

Coal Ash is More Radioactive Than Nuclear Waste.
posted by lunasol at 10:14 AM on June 17, 2010

Coal Ash is More Radioactive Than Nuclear Waste.

That's a pretty misleading way of stating it. In fact, the article was corrected :

from "In fact, fly ash—a by-product from burning coal for power—and other coal waste contains up to 100 times more radiation than nuclear waste" to "In fact, the fly ash emitted by a power plant—a by-product from burning coal for electricity—carries into the surrounding environment 100 times more radiation than a nuclear power plant producing the same amount of energy."

Fuel rods are many many times more radioactive than fly ash, but since there's no byproducts released from the smokestack in a nuclear plant, much less radiation is released.

The article goes on to say:

The chances of experiencing adverse health effects from radiation are slim for both nuclear and coal-fired power plants—they're just somewhat higher for the coal ones. "You're talking about one chance in a billion for nuclear power plants," Christensen says. "And it's one in 10 million to one in a hundred million for coal plants."

posted by electroboy at 10:44 AM on June 17, 2010 [1 favorite]

Electroboy, the headline may be somewhat sensationalistic, and I shouldn't have posted it without context, so I apologize for that. However, there does seem to be a hint of a relationship between coal ash and uranium-related birth defects that needs attention, as seen in one area of Punjab, India, and reported by The Observer:

The children had massive levels of uranium in their bodies, in one case more than 60 times the maximum safe limit....The test results for children born and living in areas around the state's [coal] power stations show high levels of uranium in their bodies. Tests on ground water show that levels of uranium around the plants are up to 15 times the World Health Organisation's maximum safe limits. Tests also show that it extends across large parts of the state, which is home to 24 million people.
posted by lunasol at 12:46 PM on June 17, 2010

Found an exceptional process:
Plasma Gasification and Vitrification of Ash into Glass-like Products and Syngas

This process uses plasma to generate high temperatures that both convert residual carbon into syngas (a hydrocarbon gas) and convert the remainder into what they claim is a non-leaching glass-like product.

The figures are quite impressive - all inorganics except for lead leach at below-detectable limits, lead leaches at 5 times below the regulatory limit. In addition to this, depending on the carbon content in the ash, the energy of the syngas produced varies from 5 times the electrical energy used to 1/2 the electrical energy used.

It's...it's almost as if they could do it if they were motivated by something other than greed profit.
posted by nTeleKy at 1:11 PM on June 17, 2010

A hint, sure, but the article also goes on to suggest that there are other possible sources for the radiation. Without knowing what sort of pollution controls India has on coal-fired plants, it's difficult to tell whether it's broadly applicable.

The USGS link posted above puts it into context with this graphic and this statement

On this plot, the average population dose attributed to coal burning is included under the consumer products category and is much less than 1 percent of the total dose.

That certainly doesn't address the lead issue, or the disaster in Tennessee where a massive impoundment gave way and destroyed an entire ecosystem, but it does suggest that the radiation issue isn't a huge concern for those of us in the US.
posted by electroboy at 2:18 PM on June 17, 2010

we can't let it sit on the ground

Actually, the point of the series seems to be "we can't let it sit on the ground in the completely unregulated way we've been letting it sit on the ground." There's no reason to pretend everything's hopeless.
posted by mediareport at 3:06 PM on June 17, 2010

It's...it's almost as if they could do it if they were motivated by something other than greed profit.

You're assuming that positive bench-scale, proof-of-concept results equals viable large scale process. Given that you'd need about 5 million metric tons of sand per year to process the fly ash that's not already used in manufactured products, I'd say there are still some issues to work out. Plasma arc waste disposal isn't a mature technology yet. It's certainly worth more investment, but the corporate greed knee-jerking isn't really appropriate here.
posted by electroboy at 6:43 AM on June 18, 2010

It's certainly worth more investment, but the corporate greed knee-jerking isn't really appropriate here.

Really? Am I "corporate greed knee-jerking"? The question posed was WTF do we do with the MILLIONS OF TONS of coal ash that aren't being made into environmentally responsible products, and that ARE being stored in giant outdoor unlined pits with little to no regulation that have been shown to occasionally leak toxic chemicals into the surrounding areas, collapse and kill people, and do nothing but just sit there and exist as a constant risk for the indefinite future. This is not a solution to "WTF do we do with the millions of tons of coal ash our coal power plants are producing?"

I attempted to find some answers that were not "LET'S JUST SWEEP IT UNDER THE RUG!" which (aside from the high visibility) is analogous to storing it in huge, unlined pits. Some of these answers are the manufactured products you mentioned, some of these answers are the plasma arc waste disposal, some of these answers are creating new power plants that integrate waste disposal so the giant volumes of fly ash are converted into a vitrified, low-leach material that can be used in other manufactured products and recovers unused carbon, many of them don't exist yet, even more have not been implemented, but there are answers.

The problem I see is motivation. Why bother when it's just as easy to sweep it under the rug? As a human being I can say "It's worth it because I would like a habitable planet for future humans to enjoy." and while there is no reason a corporation cannot come to that conclusion, many of them are under huge pressure from the people that own the corporation to come up with the answer that makes them the most money/increases the shares the most/?$$$?. When the expectation is that the entity exists for the purpose of making money, the entity will act as if its purpose is to make money. However, if the entity existed to provide a desired service in a manner consistent with the needs (like a habitable planet that is not covered in waste) in favor of the wants (like cheap energy and large ROI) of the humans it is providing that service to, I think the situation would be different. To me, this is an exemplification of, if not greed, at least the service of profit over people and the service of corporations over individuals and communities. In the famous words of so many infomercials, THERE HAS TO BE A BETTER WAY!

The plasma waste disposal mentioned is hardly bench-scale; there are numerous pilot plants running right now. Your link mentions two plants in Japan that are capable of processing over 160 tons/day, one of which has been operated since 2000 and the other since 2002. Those plants can't process all of the fly ash in existence and I'm not recommending they do. As you mentioned, there are manufactured products that can utilize fly ash without creating environmental risk and I don't recommend they stop producing those. What I see from here, though, is that we have too much fly ash to make into products, and we have viable technology (some of which includes products, yes) to process it in a safe manner that in many cases produces energy, and in the worst case doesn't cost all that much and still produces usable - in fact easier to utilize - material.

Furthermore, a plasma process is not even required - high-temperature IGCC plants can also produce a non-leaching slag. We even have some here! To sum it up, here's a conclusion from a study of an IGCC (non-plasma) power plant in Korea, where they have had pilot-scale operations since 1993:
Slagging coal gasification pilot plant has provided the fundamental technologies that was a basis for the development of slagging combustor/gasifier using the waste feed like a sludge and waste oil. Coal gasification system yielded carbon conversion of above 98% and above 70% cold gas efficiency for the Indonesian subbituminous coals that were the best-suitable coals for gasification among the tested nine imported coals.Wastewater sludge was successfully treated at the developed combustion/melting process with above 90% slag-conversion and without any leaching problems of heavy metal components in slags. Gasification/melting process utilizing the calorific value of waste oil as a heating energy in melting has been installed and tested, in that powder-type wastes are converted into environmentally benign products with minimum extra fuel consumption. Developed combustion/melting process proved that designated-waste sludges can be treated cheaply compared to incineration, although general-waste-class sludges are yet to be competitive with conventional land-filling. Wide application of the technology requires more stringent environmental regulation that will in turn stimulate advanced process developments.

Thank you for your reply, though; I doubt I would've done any more research without some prodding. I don't think there's a holy grail in this mess, and I'm sure it will be costly and difficult to implement solutions, but I learned a lot about the waste created by traditional coal plants and some inventive solutions to the problem(s) of dealing with that waste. I also kind of wish I would've finished my chemical engineering program, sometimes...
posted by nTeleKy at 12:04 PM on June 18, 2010

Really? Am I "corporate greed knee-jerking"?

Yes, yes you are. You've basically presented some promising tech that hasn't been demonstrated to operate anywhere near the capacities needed and then stated that the only reason they weren't successful was corporate greed. 200 tons/day (~50,000 tons/year) seems like a lot, but given that we produce 50,000,000 tons of fly ash alone, you're talking about .1% of demand. It's certainly worth further research, but given that 200 tons is the absolute largest plant that has been built, I feel pretty confident in saying that these aren't viable solutions yet.
posted by electroboy at 1:33 PM on June 18, 2010