Here's a problem I didn't know existed. Coal fires are underground fires that burn in coal mines and seams. In China alone, they may spew as much CO2 into the atmosphere as all the cars in the US.
These fires are exceedingly difficult to put out. Indeed, some well-known ones have been burning for decades.
Finding a way to put out coal fires and prevent new ones would seem to me to be an area where some worldchanging innovation could yield profound benefits for everyone. A brief online search turned up some interesting projects -- Remote sensing GIS tools to support fire fighters, an ambitious-looking Sino-German project, some new coal fire-fighting techniques -- but I'm not at all confident that these are the best (or even good) ideas.
But I know some of you guys must have ideas and information. Are there better tools out there? What might be done to address this problem? Why isn't this a better-known issue? If we were going to make fighting coal fires a priority, what would we do, and how would we best go about it?
I wonder if instead of fighting it you could try to get some energy out of it?
The US has its share of uncontrollable coal fires too. See for example:
about a whole vanishing town in PA. A classic example of our national tendency to ignore environmental problems in places we'd like to forget exist (see also: Montana copper mines).
Smithsonian magazine had an interesting article on these about a year ago, focusing on the Pennsylvania case but also mentioning the problem in China.
The scale of these things is so vast, I think the only practical way to put them out would be to figure out their boundaries and mine out around them, to at least confine them. Sort of like fire breaks to handle forest fires.
There are burning coal mines up on tiger mountain, in washington state, not far from seattle.
Thanks for the comments, everyone, and keep 'em coming.
I will note that I link to both the Smithsonian article and the Centralia fire in the original piece...
How might one go about getting energy out of coal fires, I wonder?
Burying water lines in areas of elevated temperature would be a good source of energy. It's geo-thermal in its way. I suppose the question would be whether the heat source is reliable, or how to go about shifting pipes as the fires moved.
As I said over a month ago many people ignore all the unmeasured and ignored sources of co2 around the world. This is just one of a legion of hidden pitfalls in global warming.
When we lived in Boulder, CO, Marsha and I used to hike the Marshall Mesa Trail. That's where we first learned of coal fires - Marshall was a happening coal town 100 years ago when the fire started. I recall hearing that attempts to end the fire with water were unsuccessful because of the heat - the water turned to steam before it had any practical effect. The fire's still burning 100 years later, and appears to be cyclic, with alternate periods of activity and inactivity.
FYI I found a session list for a 2004 conference of the Geological Society of America where they'd discussed "Wild Coal Fires: Burning Questions With Global Consequences?" The GSA might have more on coal fires.
Why don't you smother those fires with Co2 produced from a Coal Gasification IGCC power plant and then later send the Co2 to the abandonded oil fiels for enhanced oil recovery to bring up the heavy oil not accessable by conventional means. Another idea, for that matter, is to use the exhaust from the stack of a conventional thermal power plant which could be piped underground and quench the fires.
You had a post some time ago about using algaes to recover CO2. Could it apply? Contrary to energy plants this coal is going to burn anyway as long as we don't find practical ways to extinguish the fires. So we have to also focus on both recovering energy (with geothermal type installations as mentioned in another comment) and limitate the amount of global warming induced (with algaes or other means).
I don't think its possible to use the algae to recover some benefits because the size and location of the problem. The algae solution required pipes to carry very specific waste streams into large tubes containing water, nutrients and algae. You couldn't create a tube large enough to cover this sort of problem. If there was one area of ventilation to the fire, you could do it, but then again, if that were the case, you could simply cut off its oxygen source and stop the fire. As we know, this is currently nearly impossible. I like the idea of pumping excess CO2 down there to suppress the fire, but we may need to examine the surrounding areas to determine how wide the scope of each fire is.
They have put out a few coal fires over time but frankly there is no way to put out the large ones short of flooding the entire land around it and waiting for the fire to consume its o2 supply. In hilly lands thats not possible of course and thats where alot of coal is.
I agree with the idea of using the burning coal mines as carbon sinks into which we can pump lots of CO2 as part of carbon sequestration, in order to snuff out the fires. Perhaps some kind of 3D thermal imaging should be done in order to map out how the burn is occurring underground. Then pipes can be drilled accordingly, to pump in the CO2 at the right places, for maximum quenching effect.
It would be interesting to see a comparative study done on coal fire CO2 VS direct industrial emission CO2 (power plants, cars, factories, etc.) to see just how much each contributes to global warming. Are we burning less, more, or about an equal amount of coal as is burning in those mines?
As for what to do about it, would CO2 foam be an option? What about building an air tight structure around the blazes, so the fires burn themselves out? (perhaps as an additional measure to pumping CO2 into the burning area).
I don't think trying to capture the energy of the fires is that good of an idea, mainly because you after you build an infrastructure to capture that energy, whoever owns said infrastructure isn't going to give it up once a way to put out the fires has been found. In addition, coal is a finite resource and captured energy or not, is still going to spew CO2.
If we're going to have a bright green future, then we have to take problems like these as opportunities for renewable, sustainable, and low impact innovation. If a problem like the oil peak can drive fuel and energy innovation, then a problem like massive CO2 from coal fires should be able to drive innovation in chemistry and materials.
You cant build an air tight structure around something the size of france.
From the sounds of it, some of these are so big they can't be put out. How difficult and expensive would it be to pump water in and get energy out of the steam coming back up? Are there less obvious ways to use that fire? (I'm no engineer)
Before suggesting to somehow harness the energy of coal fires, one should think twice and have a look at location and configuration of those events. Many take place in remote places, with many moving fire spots covering a broad area, at various depths under unstable grounds. Look at e.g. places in China located at http://www.coalfire.caf.dlr.de/projectareas/project_area_en.html. They are described as "easy to access", well, sort of. Any effective infrastructure in such places is likely to be so complex and costly to set and maintain that it would certainly have a very poor, if not negative, energetic balance. Seems more reasonable to figure out how to prevent further such events, try and confine the existing small ones, and take into account the big ones in the global carbon balance "structural costs", so to speak, along with volcanic eruptions.
In Colorado in '02, the appropriately-named "Coal-Seam" fire came alarmingly close to Glenwood Springs. Driving down I-70 you can see the damage on the hills surrounding the town. Apparently, that fire has been burning for 90 years, and occasionally pops out of the ground somwhere and sets the dry brush/trees on fire. I think it was originally ignited by a lightning strike. It's hard to imagine how one could smother it with a surface that is more vertical than flat.
Anupma Prakash, who seems to be one of the few academics devoting time to this, gives the following reasons why coal fires aren't getting researched like they should:
All of those seem like areas where Worldchanging is in a perfect position to help - it'd be a real shame if we passed up on the opportunity.
As a first step, I'd suggest a wiki page somewhere to pool information. That would get us going on point two, the scattered information. Anyone able to offer up a corner of a wiki?
Glenn Stracher wrote in with some helpful references: