Future Energy Sources 1.7.1 Clean Coal Technology

It's just about money. When the price of oil and natural gas gets high enough to make clean coal a viable alternative. A nuclear powerplant meltdown would also speed things up. Be patient.

Unfortunately the world doesn't have time to be patient. Australia is already seeing dramatic shifts in the climate. Mean temperatures are already 1°C higher than those of the middle of the 20^th century. There is evidence that the Antarctic ice sheet is melting and the Greenlandic ice sheet is also retreating, dumping large volumes of fresh water into the North Atlantic and threatening to shut down the gulf stream.

I don't think it is too late to act but we certainly can't afford to sit around and wait for the economics to change before we do anything.

I was saying be patient for clean coal. I would hardly consider clean coal as the ultimate solution to our climate problems and certainly not the nearest at hand. However I don't know what the lowest environmental impact lifestyle or carbon footprint would be for 6.5 billion people. Agrarian, but don't burn wood for heating or cooking. What do you suggest?

Hi Sail4evr,

You are absolutely right that if we reverted to an agrarian society the 6,5 billon people would have a catastrophic effect on the CO₂ levels and global warming would be much worse.

This is a very complex problem and it requires some serious lateral thinking to solve. Frankly I don't know what the solution is but I do know there is a myriad of possibilities. Unfortunately most of the powers to be seem to have a blinkered outlook of what needs to be done and would much prefer to sit around procrastinating than getting on with the job.

That's what this blog is all about, opening the eyes of engineers to the many possible technologies and what needs to be done, thus giving us the best chance of finding a real workable solutions.

Coal can be developed as a clean burn fuel - though you still have to deal with the CO2 somehow. Fluidised bed combustion of pulverised coal with the addition of 10 % biomass of wood chips is said to give a very clean burn.

While we cannot all cut down trees and burn them for heating, in a land like Australia there is plenty of space to grow new ones and the Autralian gum trees, like our European Willows are very fast growing for replacement. A 15 year cycle of plant and cut and replant is quite possible.

If you plant more than you cut down then a wood fuel economy is a carbon neutral - or even negative - form of heating. You just have to have the discipline to make sure every tree cut is more than replaced. Easy really!

Hugh Mattos

Chartered Engineer

Hi Hugh,

While we cannot all cut down trees and burn them for heating, in a land like Australia there is plenty of space to grow new ones and the Autralian gum trees, like our European Willows are very fast growing for replacement. A 15 year cycle of plant and cut and replant is quite possible.

It's a nice idea but unfortunately the majority of Australia is desert and arid land so it unsuitable for growing trees. Also the majority of eucalypts are very slow growing and 15 to 20 years is no where long enough for them to grow to a usable size but there are some that do grow fairly rapidly. Another hassle is that they contain eucalyptus oil which is highly volatile and this is one of the reason Australian bush fires are really nasty things.

I did a calculation in another thread on how much area we would need to use for growing timber if we were to use it as a replacement for oil and coal and it was about the size of North America. Add in infrastructure and land not suitable for forestation and you need something more like North and South America combined.

Hi Masu,

Yes I have been to Australia - though granted that was before global warming ! - and you still have plenty of land to grow enough ytrees to keep you carbo balance neutral.

Consider that you only need to grow a greater mass of trees than the mass of oil. wood and coal that you burn.

The population of Australia is say 20 to 20.5 million. Each family of four say uses 1000 litres of vehicle fuel plus 1000 litres of heating fuel plus the equivalent of 1000 litres of electricity ( at 33% efficient we will call that 3 tonnes for electricity)

To me that makes 5 tonnes of wood needs to be grown by each family each year.

We grow Eucalyptus here and it can be pretty fast after the first 3 years, like willow and birch. Let it grow to 250 kilos ( little is wasted in wood chip plants and microCHP systems) and cut and replant. So you need enough space to plant 20 trees each year and with a 15 year growing period, an area of 300 trees for each family. About 1600 million trees in all of Australia - I suggest that you would not even notice they were there.

Have I got my sums wrong or has all of the Blue Mountain forest and the east and west coastal regions suddenly dried up?

HUgh Mattos

Chartered Engineer

Hi Hugh,

Have I got my sums wrong or has all of the Blue Mountain forest and the east and west coastal regions suddenly dried up?

Yes the eastern seaboard has pretty much dried up. Unless there is a serious change in the weather pattern Sydney will run out of water around the middle of 2008. The Darling river has dried up completely, see image at right, and the drought is the worst in 1,000 years. Meanwhile the north west of the continent has been hit by two cyclones in the last week and they expect a third to hit around now. Three cyclones in a week is pretty much unheard of.

The blue mountains and the great dividing range havn't lost all their forests but some very large tracts of it were destroyed by bush fires in Victoria this summer.

1.6 billion trees is not a great problem but we are currently cutting down trees faster than we are planting them so first of all we need to reverse that trend before we can think about increasing the demand for timber. Ultimately I think there is a place for wood as a fuel but there are other corps, like hemp, that grow considerably faster and have a higher yield per hectare that trees.

Hi Masu,

That is a sorry sight. When I was in Australia - 1989 - the Darling river was a real river with boats and ferries and watersports!

Looks like you may be better off with a single season crop to provide biomass. A good bit safer if you are going to have droughts to kill off my coppice trees. Maybe a grass - maize mix and them make ethanol and use the residue to clean up some coal fired power stations?

Hugh Mattos

Chartered Engineer

Hi Hugh,

When you were in Australia did you did you have a chance to visit the Snowy Mountains and see the hydroelectric and irrigation scheme? Currently the water levels in the reservoirs is so low that towns that were flooded during its construction are now well above the water. There was a article on one of the news services showing a reporter standing on a dry baked river bed that is normally over 50 m below water.

It has started to rain but it has only been enough to just arrest the rate the water levels are dropping let alone start to refill them.

Hi Masu,

While I was in Australia for 8 weeks and did get from Sydney to Darwin to Ayres to Melborne to Albany, Perth etc, I cannot say that I had a chance to see the dams.

Sounds to me that things are a bit grim there so it is no wonder that the politicians have at last woken up to the need to start at least to think about what action can be taken.

I have to accept that we are in the middle of a very mild winter here in the UK, but we have had more wind and more persistant rain than I can ever remember.

Our Met. Office tell us that we have had 7 of the hottest years on record - our records go back to 1659 - in the last ten years, so even I have to accept that there is some long term change going on.

Regards

Hugh Mattos

Chartered Engineer

The Snowy Mountains Scheme was one of the worlds greatest engineering projects of the time and is a joint hydroelectric and irrigation system. Basically it took the eastward flowing melt water from the Southern Highlands and through a system of tunnels and dams, diverted it so it flowed westward and could be used for irrigation. The process required the pumping of vast quantities of water so they used the water itself to generate not only the electricity needed for the pumping but a massive surplus which is supplied to New South Wales and Victoria. By pumping the water during periods of low electricity demand and generating during peak demand periods it is also being used to store surplus generating capacity.

It had a profound effect on Australia as the expertise to build such a vast scheme needed to imported. This sudden influx of skilled migrants was the beginning of dramatic cultural changes and the start of Australia becoming the multi cultural society that it is today.

If did have some negative effects that we are only looking at rectifying now but for the most part it has been a huge success. An interesting point is that if you wanted to build a scheme like this now I doubt that it would ever get of the drawing board as getting approval for it would be an absolute nightmare.

Hugh,

Are you confusing the Darling River for Darling Harbour? Darling Harbour is in Sydney and most NSW tourists will see it, complete with ferries and watersports.

The Darling River on the other hand, is something entirely different. It frequently runs dry. The River Boat Captains of the 1880 - 1890 period were justifiably frightened of this "watercourse" because river boats were frequently stuck for 3 to 5 years at a time when attempting to transport wool to Euchuca on the NSW Vic border (an inland entrepot).

The Darling rises around Dirranbandi in far South Western Queensland, and all of Southern QLD is in severe drought. The whole Murray misses out as the Murray is also fed by the Lachlan / Macquarie / Condamine system which rises in South East QLD behind the Gold Coast. If rain from Bundaberg to Brisbane fails Adelaide dies of thirst.

This event is not new, the 1895- 1900 drought was terrible. Coral coring on the Great Barrier Reef indicate that during Europe's "Mini Ice Age" the Burdekin River did not flow for decades.

Australia is harsh and inhospitable, it may kill us all yet.

If I remember correctly, when I was there, the Darling was 50 metres across and had a ferry - well floating platform really - which carried say 8 cars or one coach. As we were on an Australiam Pacific coach 30 day tour we had to leave the coach as payload was an issue on the ferry. The ferry came back for us and picked us up as passengers on the next trip.

The local farmer had a sportsboat which his family used for watersports skiing etc.

I hope you are being unduly harsh on yourselves, we loved our visit to Australia. Yes parts are very dry and deserted, but the coastal fringes, and Albany in particular - where we wnt to stay with friends on their 10000 acre sheep farm - were wonderful in September to Novemeber 1989.

I am only sorry I have not been back since.

Hugh Mattos

Chartered Engineer

Hugh,

You definitely saw it in a good season. As I said before it was frequently navigable by river boats before road and rail transport infrastructure was developed.

Yes the South West of WA is brilliant. Did you get to Esperence? Cape Le Grande national park just East of there is fantastic. We must get back to the West too.

Regarding the drought, the North of the Continent is Ok at the moment as the Monsoon arrived this year and we are having a wet season right across the top end. The area, say from Bundaberg to Sydney is missing out big time.

We have had a very big frog breeding season this year, hopefully a good sign.

Lake Eyre is filling and historically that is a harbringer of good seasons, I hope so.

"Australia is harsh and inhospitable, it may kill us all yet."

It's certainly having a good go at it this time. A couple of weeks ago in one week we had three tropical cyclones, bush fires, drought and floods. Some how I get the impression nature is not happy with the way we are managing things.

Nature not happy, Masu?

From your description, it looks like she's having a regular party!!

Mark

Maybe, but this sort of party is definitely the type you hope you neighbors don't throw.

Back in the mid-1970's, the last go round of the environmental "call for action" against the woes of greenhouse gases, I served as a principal investigator on one US Government sponsored "Clean Coal project. The technologies for converting coal to a near natural gas substitute for use in the steel industry was a success, however, the economics (and government bureaucracy) squealched the project, along with numerous coal to gasoline and coal to fuels demonstration projects.

At that time I realized, as a fuel technologist, that the most practical method of using coal as a source for fuel in the US and worldwide was to utilize modifications of the technology in use at Sasol. Interestingly, I mentioned it to a friend who was on the President's Advisory Board for Synthetic Fuels; he was the chairman of the Chemical Engineering Department of a major university studying the subject. He had never heard of the Sasol technology.

I believe the only way coal will ever achieve its true capability to address the energy problem is to get people who know more about fuel technology and coal's historical usages into positions where politicians will listen to facts, not what the under informed public and/or oil company lobbyists ahve to say. After coal started to make some gains in the fuels market, the oil companies purchased most major coal companies in the US using windfall profits they made from increased oil prices in the 1970s.

I'm not saying the Sasol technolgies (based on coal gasification via Lurgi and iron-based catalysts for the Fischer Tropsch process) is a panacea, but that going in that direction without the interference of the oil companies in the market could bring it to fruition. But it will never happen as too many lobbying dollars will prevent it. Adjustment of the fuel tax structure in the US or elsewhere could easily change the entire picture for use of coal as a fuel. Believe me, coal fuels can be made clean, it's just a matter of cost to the producers and how the government wants to structure the pricing.

OK guys & gals...help me out here.

Who was the woman who was named 'Scientist of the Year' around the year 2000 or 2001 for coming up with a pre-combustive catalytic solution to coal pollution?

Mark

I heard a retired coal guy speaking on c-span about

super drying the raw coal to lower thshipping costs & a side benefit was a 85% reduction in mercury content.

here's a useful link for this subject

http://en.wikipedia.org/wiki/Syngas

traditional combustion could fuel

http://en.wikipedia.org/wiki/Algaculture#Biodiesel_production

or other closed system agriculture [greenhouses]

Just a couple of questions about all the trees we are going to plant.

What is going happen when the trees reach maturity and go CO2 neutral (the tree rots, sheds leaves and limbs at the same or greater rate that the CO2 it absorbs)?

What happens when the tree dies?

What happens when we do run out of land suitable for trees? While concidering maintainence of food production.

Should we grow them, cut them down and bury them and grow again.

If money was no object would a total switch to renewable fuels be possible in the short term?

Where are we going to spend our money when the planet dies?

Ian

Hi Ian,

What is going happen when the trees reach maturity and go CO2 neutral (the tree rots, sheds leaves and limbs at the same or greater rate that the CO2 it absorbs)?

This is an interesting point and something that I feel has not been looked at or dealt with comprehensively. I understand that there is considerable research being done into the atmospheric dynamics of stable old growth forests. However, I don't think anybody actually has a definitive answer for how much CO₂ a stable forest environments actually sinks from the atmosphere.

I did do a calculation, in another thread, that showed that if we were to use timber as our primary energy resource and a replacement for fossil fuels, the area required would be about 18,000,000 Km². Now admittedly this is if we used solely timber as an energy resource but it is still a very large area. If you were to take into account arid areas, land unsuitable for tree plantations and added infrastructure you would need pretty much all of North and South America.

However this doesn't address the problem. According to Wikipedia's carbon cycle about 120 Pg of carbon is released into the atmosphere through old growth and stable forests while 121.3 Pg are removed. Tree plantation remove an additional 500 Tg of carbon from the atmosphere.

On the face of it, it would appear that stable forests do indeed continue to sink carbon from the atmosphere but by utilizing the timber in some non combustive way and growing replacement timber we could increase the amount of carbon being removed from the atmosphere.

However considering that about half the carbon that is in trees comes from the ground if we were to use the wood as a fuel we would be increasing the amount of CO₂ being release into the atmosphere dramatically.

So from my interpretation, using timber as a fuel, even if we replaced the used trees, would increase the amount of CO₂ in the atmosphere. What we really need to be doing is growing trees and utilizing the timber in some no combustive way then replacing the used trees with younger actively growing trees.

Others may see this differently and this is just my interpretation on the figures and may be completely off the mark so if you have a different interpretation please post it. The broader the outlook and the greater the number of points of view the more comprehensive any conclusion that can be drawn will be.

From Australia's point of view it is real easy (CO2 positive to neutral to the present mess), get rid of the Labour party (they can't spell) and the greenies that they want to woo, then reopen sustainable yield forestry.

Apart from the global warming improvements we will automatically cut funds to terrorists in Malaya and the East Indies (oh dear, they call themselves Malaysia and Indonesia, but it changes nothing).

Hi all,

Here in the USA many people think that new multibillion dollar "Clean Coal Burning Facilities" are the answer to our energy problems. At this point in time it is only a concept. I think you can bet your boots this new technology will cost us big bucks and is only a temporary solution. I think we will find that "Clean Coal Burning" will drive the cost of energy higher than we ever imagined and there's the rub. The US Government is pushing hard to implement this technology. Winston Churchill once said "You can always count on Americans to do the right thing - after they've tried everything else." Well, I guess he's right, we will try everything else first.

Sincerely,

Gary

Hi Gary,

I don't think I have noticed any of your posts before so hello. I too have reservations about the technology but it is important that we look at all the possible solutions to our problem, you never really know till you have tried. By flatly dismissing the concept we may, in our haste, overlook the very solution we are seeking.

Hello MASU,

I agree with what you say. Edison tried hundreds of different elements before he perfected the light bulb. Now look where the light bulb is going.

However, I am a big fan of renewable energy and I think it is the way we should all go, eventually. You can't have much cleaner energy than solar or wind energy. Fuel cells will someday be perfected to get their fuel from solar and/or wind. I think that is the route to go. I know we have not tried them on a large scale but we shouldn't overlook that concept either. I do think renewable energy is possible on a large scale.

Sincerely,

Gary

Hello Gary,

Have you been following my blog so far? The concept that I believe currently shows the most promise is co-generation with everybody using a technology that best suits their location.

It is a good idea to subsidise research into all these new technologies. However, it is very important to remember the tidal and wave power schemes.

We must also aim to support the smaller scale projects like microgeneration at an individual building or neighbourhood level. These can be mass produced and are much more energy efficient than the centralised systems we use today - with all the transmission losses involved.

Hugh mattos

Chartered engineer

...Or following my last entry, Gary, in which I enquired about the pre-combustive catalytic solution to the signifigant reduction of air pollutants already found and peer-approved for coal useage? As I recall, the process was not an expensive one to implement, and very efficient.

BTW, anybody recall who the inventor was, or what she came up with? I can't find the article in my archives anymore. It seems to me that she may have had a South-Asian (East Indian) - sounding name.

Mark

If we look at the system as a hole, coal will never be a clean source of energy. Sequestration can now be done but what is done with the captured CO2? It is used to force the remaining oil from low level wells. It is then trapped in the earth. What will happen when it will brake free? We will not be here to see it but our children will. There are other way you can get rid of CO2 but none are RENEWABLE. Only renewable energy will do the job. Yes it is not cheap and the out put energy is not constant and unpredictable. Lets concentrate on that and find storage solutions and hybrid systems. Let us invest in knowledge and education !!! That is the key.

But first we need to build energy efficient house, industry, car, electrical appliance, ect... we need the have laws that will lead those initiative and force people to act a certain way. Only problem for Canada is that our economy is directly proportional to the United State's economy. If the Americans don't try it, we'll surely not try it !!! Canada... stop fallowing and lead for christ sake !!!

Bottom line, energy production will always be a problem because we are consumming more than we naturally need. It is that simple. We consume like there is no tomorrow. The industrial revolution of the fifties is where it all began. Baby boomers are financed by the money output created by the indutrial revolution. The Y generation (1970-1990) will need to reduce consumption and clean up the mess. Young politicians will need to fight for a cleaner environment. Like a baby boomer scientist said : 'I can't understand young people, if I were young and living in today's environmental reality I would be out in the streets screaming... and yet they are ignoring the problem.'

I predict a new era in a couple of years where young people will fight for a cleaner future !!!! Hope is what we need... and a little political push...hehe

we cant turn our back on coal, and it will be part of our future energy solution .

All fossil fuels are a dirty stop gap measure while mankind moves from the industrial revolution to a sustainable economy. The only realistic long term options are those that rely on the large natural energy sources: solar, wind, tidal, wave, and geothermal, or as yet undeveloped technologies (will fusion ever be practical, clean and give more than a few thousand years?). Solar is by far the biggest source, and wind is a good second.

Biofuel is a deceptive dead end. It is nothing more than an easy, very inefficient solar energy solution, which converts less than 0.5% of the solar energy to fuel energy (actually much worse - once transport and fertilizer energy are included, 0.1% is more likely). It is obvious that this will not compete with the rapidly improving solar energy solutions. Put simply, if someone suggests using 40 square kilometers to make biofuel the obvious response is to use 1 square kilometer for a solar power station and use the other 39 square kilometers for something else. This has the advantage that there is enough land on Earth to supply human needs this way, but not enough for biofuel.

I think most people have heard about the two largest scale solar energy projects so far, which will provide a total of 1750 MW. Similar projects are possible anywhere that has a suitable climate, including most of the world's deserts. http://www.stirlingenergy.com/projects/default.asp

Hi Elroch,

• Biofuel is a deceptive dead end. It is nothing more than an easy, very inefficient solar energy solution, which converts less than 0.5% of the solar energy to fuel energy (actually much worse - once transport and fertilizer energy are included, 0.1% is more likely).

Bio-fuels have one massive advantages over other renewable energy resources in that for the most part you have a liquid or gaseous fuel that is easy to store, transport and use in vehicles like cars, trucks, busses, trains and especially aircraft.

Now before somebody pipes up with hydrogen let me say hydrogen isn't the simple answer many believe it to be.

Not only is the generation of hydrogen woefully inefficient but it is extremely difficult and dangerous to store. One of the problems with H₂ is the size of the molecule and there is no way to make a container that will not leak. In one case of a H₂ fuelled car the tank would loose about 40% of its contents in around 2 weeks which is to say the least undesirable.

In the mean time may I direct you to the Table of Contents page for my blog on future energy. You will find links to a whole host of threads that look at various technologies that may be helpful in treating our addiction for fossil fuels and I would like to hear what you think on the various technologies.

Hi, Elroch!

That's a very impressive web page. Thanks. If you're a principal player in this in any sense, I'd just like to alert you to three typos in one of the paragraphs on the last page:

"Phase I of that program incorporated design enhancements to the Stirling dish system to increase performance and decrease [and] maintenance costs. Phase II[,] focused on system integration and successful[ly]completion of the program."

All the best in your endeavour. I'd be interested in knowing more about the cooling apparatus in the Sterlings, if you're willing to enlarge on that point.

Mark

Glad to see you share my enthusiasm and read the page carefully! I am not directly involved in this exciting project, but I have passed your editorial comments to SES.

below is a cut and paste of an article about clean coal. says it far better than i could.

http://www.treehugger.com/files/2007/08/there_is_no_suc_1.php#ch01

We were surprised to see this covered in Forbes Magazine, an information source for big investors.

"As the nation's coal-fired power plants work to create cleaner skies, they'll likely fill up landfills with millions more tons of potentially harmful ash. More than one-third of the ash generated at the country's hundreds of coal-fired plants is now recycled - mixed with cement to build highways or used to stabilize embankments, among other things."

"But in a process being used increasingly across the nation, chemicals are injected into plants' emissions to capture airborne pollutants. That, in turn, changes the composition of the ash and cuts its usefulness. It can't be used in cement, for example, because the interaction of the chemicals may keep the concrete from hardening."

Are we thinking about bridge replacement and repair using coal ash as an amendment to concrete? Because if we are, we better think twice.

"That ash has to go somewhere - so it usually ends up in landfills, along with the rest of the unusable waste. "You're replacing an air problem with a land problem - a disposal problem," said Bruce Dockter, a research engineer with the Energy and Environmental Research Center at the University of North Dakota... And the chemicals added to clean up emissions - such as ammonia, lime and calcium hydroxide - make the ash worse, environmental groups say, because they take toxins such as mercury out of the air but leave higher levels of it in the ash."

Although the Forbes article is insightful, it stops short of explaining a potentially critical factor. Historially, coal combustion wastes rarely exhibit the characteristics of hazardous waste. However, if coal burning utilities and the so-called "clean coal plants" were required to meet air emissions standards protective of human health, fly ash produced by them could be regulated as hazardous waste due to the elevated levels of mercury that would result. We might suppose that any fly ash with hazardous characteristics due to heavy metal content would have to be sent to special and expensive waste fills or be treated at great cost.

But we would be wrong to assume that. USEPA made fly ash exempt from regulation as a hazardous waste far before the risks of mercury and lead exposure were well understood and before air emission limits on heavy metals were contemplated. Hold that thought.

There is another unintended consequence of making fly ash toxic. Reduced use of fly ash as a concrete amendment means more cement must be added to the mix, increasing the carbon emissions footprint per Kg of concrete used.

These two reasons together explain why the coal utility industry has been opposed to more stringent mercury emission standards and why even the lenient mercury emission standards recently recommended by EPA were scheduled to be phased in so very slowly. Were high levels of mercury found in commercially sold fly ash, you can bet that a can o' regulatory worms would be opened. So, nothing to see here, move along now.

That is a beat up which defies logic. If tertiary treatment is required to remove extra pollutants that the bag houses and precipitators don't get sheer economics indicate it would be applied after the bulk of material is already recovered.

hi everyone,

from a new article in nyt. first i will include the url to the story.

http://www.nytimes.com/2008/12/25/us/25sludge.html?pagewanted=1&_r=1&th&emc=th

next, i will copy a few comments from it.

KINGSTON, Tenn. — What may be the nation's largest spill of coal ash lay thick and largely untouched over hundreds of acres of land and waterways Wednesday after a dam broke this week, as officials and environmentalists argued over its potential toxicity.

Federal studies have long shown coal ash to contain significant quantities of heavy metals like arsenic, lead and selenium, which can cause cancer and neurological problems.

But a draft report last year by the federal Environmental Protection Agency found that fly ash, a byproduct of the burning of coal to produce electricity, does contain significant amounts of carcinogens and retains the heavy metal present in coal in far higher concentrations. The report found that the concentrations of arsenic to which people might be exposed through drinking water contaminated by fly ash could increase cancer risks several hundredfold.

Similarly, a 2006 study by the federally chartered National Research Council found that these coal-burning byproducts "often contain a mixture of metals and other constituents in sufficient quantities that they may pose public health and environmental concerns if improperly managed." The study said "risks to human health and ecosystems" might occur when these contaminants entered drinking water supplies or surface water bodies.

United States coal plants produce 129 million tons of postcombustion byproducts a year, the second-largest waste stream in the country, after municipal solid waste. That is enough to fill more than a million railroad coal cars, according to the National Research Council.

AND THE WORST OF ALL

Another 2007 E.P.A. report said that over about a decade, 67 towns in 26 states had their groundwater contaminated by heavy metals from such dumps.

For instance, in Anne Arundel County, Md., between Baltimore and Annapolis, residential wells were polluted by heavy metals, including thallium, cadmium and arsenic, leaching from a sand-and-gravel pit where ash from a local power plant had been dumped since the mid-1990s by the Baltimore Gas and Electric Company.

Hi, artbyjoe!

Yup. Read it this morning. Great ammunition for anti-dam and anti-coal folks. Bit of a red-face on the TVA today, don't you think?

By the way, do you happen to know what commercial use that caked fly ash is put to when it is dry?

Mark

hello mark,

at the moment, most uses of fly ash are in the concrete industry. at the moment about 15% of fly ash is recycled. the rest is what i assumed happened in the article indicated. piled up forever.

the problem with "clean coal" that i have heard is that when they really stop pollution going out the stack, is that the fly ash will be a lot more polluting and hazardous than it is now.