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Underground Coal Gassification

Discussions of conventional and alternative energy production technologies.

Underground Coal Gasification Feasibility Report

Unread postby Permanently_Baffled » Fri 29 Oct 2004, 04:51:49

http://www.dti.gov.uk/energy/coal/cfft/ ... report.pdf

Found this on the DTI website, looks like the government are looking at underground coal gasification. The report suggests that environmental concerns can be addressed at an effective cost. The report seems to suggest this has substantial potential in the UK. Gas produced via this method could produce as much electricity as conventional coal power stations(about 20% of UK power needs currently). It also mentions that power from this source could last decades if not centuries.

The report also mentions this technology could be used to produce not only gas but also hydrogen in the US. It also says Japan has substantial offshore reserves of coal which they would be interested in developing for a supply of gas and hydrogen.

If the environmental side can be sorted(carbon capture) , has this got potential?

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Unread postby Laurasia » Sat 30 Oct 2004, 21:18:28

Hello Permanently Baffled: I have heard mention of this process before; in fact, Senator Kerry's website mentions this as part of his answer to the concept of breaking free of the dependence on foreign oil. I believe the process involves a lot of heat, possibly in the form of steam, being introduced into the coal seam itself. One of the things that niggles at me is "what is going to generate the heat to make the steam?" The second thing that bothers me is that it seems rather dangerous (understatement). I grew up in County Durham (colliery country), and coal fires kept me warm in my childhood. Once that coal got heated up, the oil would be released and there'd be a mini-explosion of flame. I think I'm sort of imagining that on a giant scale down a coal mine. Not good!

I suppose it would work to ease the transition away from oil, and perhaps together with wind and solar, it might help UK have a soft landing. I'm just so afraid that people will not internalize the fact that there really is no substitute for oil, and that any alternative measures should be viewed merely as stopgaps and not as bona fide replacements. Otherwise they will just think it's business as usual.

Anyway just my two cents... It's nice to be on a forum where people have their "oil-antennas" out all the time, zeroing in on important news like this, so people like me can come along and try to understand.

Regards,

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Unread postby airstrip1 » Tue 02 Nov 2004, 16:29:48

As a schoolboy in the UK during the 1970's I remember my geography teacher telling the class that during the drilling for oil and gas in the North Sea they had also discovered massive coal seams over forty foot thick. At the time this was four times as wide as Britains biggest onshore deposit near Selby in Yorkshire. At the time he said that there was no current means of utilising these enormous energy reserves. Now that peak oil is now starting to look imminent peoples attention is starting to focus on this issue again. Unfortunately, due to the butchery of the coal industry in the Thatcher years much of the expertise in this area has been lost. We are going to going to have to pay for the waste of those years the hard way.
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Unread postby Kingcoal » Tue 02 Nov 2004, 21:26:17

Manufactured Coal Gas was the original natural gas that lit the street lamps of Europe and the New World in the 1800s. The gas was produced locally at the "Gas House" and sent to street lamps, rich peoples houses, etc. There was no storage that I know of. The realestate was generally cheap around the Gas House due to the less than pleasant aroma.

http://www.heritageresearch.com/manufactured_gas_index.htm
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Unread postby pea-jay » Sun 16 Jan 2005, 04:46:58

I keep thinking that coal, as currently utilized will not be the fallback energy source that everyone thinks it will be, especially in places that have long extracted and utilized the substance. Why? Because we already use a crap load of oil to get at the coal seam. Look at modern coal operations in many countries. Huge equipment is required. In Appalachia they bulldoze entire mountains to get at the seam. From an energy stand point, thats a huge expenditure to move a lot of rock to get at a relatively small resource. For deep operations, great big lifts are required to bring the coal to the surface. Again, thats a lot of energy is expenditure.

Now fast forward to an energy poor future. Where will all of that energy needed to extract the coal come from? Continued reliance on oil (diesel) will force the cost of the coal upwards like the cost of the fuel the equipment requires. Plus eventually, the decision will eventually have to be made what other use will have to go without (when continuing declines) leave less fuel supplied than can be produced. Plus for oil importing nations with coal deposits, where will the funds come from to pay for the oil to get the coal.

Coal certainly can't be extracted by coal derived synthetic oil. The process usually consumes more energy than it produces and even if it is positive, it is barely so. Now taking that syncrude, converting it to diesel to put into the equipment to run...well that sounds like an energy black hole.

Now, if the coal is extracted by human power and then burnt, maybe. From what I have read, alot of Chinese mines are largely human powered (which also explains their high fatality rate, too). But that's just one country. We already mined the most easily accessed coal supplies by human power more than a hundred years ago. Heck, even the number of machine driven (but people run) deep coal operations in this country have dwindled in favor of the large surface mining pits. If we have to go back to human powered operations of the mid 1900s or late 1800s how in the world are we going to produce at the current level of production, let alone increase to meet this anticipated increase in demand for coal.

Maybe I am missing something. But I don't think conventional coal production is going to cut it, post peak.

What about non conventional? This I am not so sure about. If scientists are sucessful enough, perhaps they could figure out how to get at the coal unconventionally. I certainly hope not. From what I have read though, so far no efforts have been successful (commercially) to date. Specifically I am refering to Underground Coal Gassification, but it could be anyother mean of accessing coal without conventionally mining it.

I think the jury is still out on that one.
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Unread postby jato » Sun 16 Jan 2005, 06:02:18

Coal production would have to follow some type of peak with a curving decline right? I assume the last of the remaining coal would be more difficult, more expensive & more time consuming to mine.

How fast could USA coal production grow? What would be the maximum level before production declines? Has anyone crunched the numbers yet?
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Unread postby jato » Sun 16 Jan 2005, 06:12:12

To answer my own question:

Coal peak


Coal will peak (taken from the bottom of the link):

Hubbert model=2032 (worse case)

EIA=2060 (best case)
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Underground Coal Gassification

Unread postby Subjectivist » Tue 25 Mar 2014, 08:22:19

pea-jay wrote:I keep thinking that coal, as currently utilized will not be the fallback energy source that everyone thinks it will be, especially in places that have long extracted and utilized the substance. Why? Because we already use a crap load of oil to get at the coal seam. Look at modern coal operations in many countries. Huge equipment is required. In Appalachia they bulldoze entire mountains to get at the seam. From an energy stand point, thats a huge expenditure to move a lot of rock to get at a relatively small resource. For deep operations, great big lifts are required to bring the coal to the surface. Again, thats a lot of energy is expenditure.

Now fast forward to an energy poor future. Where will all of that energy needed to extract the coal come from? Continued reliance on oil (diesel) will force the cost of the coal upwards like the cost of the fuel the equipment requires. Plus eventually, the decision will eventually have to be made what other use will have to go without (when continuing declines) leave less fuel supplied than can be produced. Plus for oil importing nations with coal deposits, where will the funds come from to pay for the oil to get the coal.
I
Coal certainly can't be extracted by coal derived synthetic oil. The process usually consumes more energy than it produces and even if it is positive, it is barely so. Now taking that syncrude, converting it to diesel to put into the equipment to run...well that sounds like an energy black hole.

Now, if the coal is extracted by human power and then burnt, maybe. From what I have read, alot of Chinese mines are largely human powered (which also explains their high fatality rate, too). But that's just one country. We already mined the most easily accessed coal supplies by human power more than a hundred years ago. Heck, even the number of machine driven (but people run) deep coal operations in this country have dwindled in favor of the large surface mining pits. If we have to go back to human powered operations of the mid 1900s or late 1800s how in the world are we going to produce at the current level of production, let alone increase to meet this anticipated increase in demand for coal.

Maybe I am missing something. But I don't think conventional coal production is going to cut it, post peak.

What about non conventional? This I am not so sure about. If scientists are sucessful enough, perhaps they could figure out how to get at the coal unconventionally. I certainly hope not. From what I have read though, so far no efforts have been successful (commercially) to date. Specifically I am refering to Underground Coal Gassification, but it could be anyother mean of accessing coal without conventionally mining it.

I think the jury is still out on that one.



ROCKMAN, there used to be a lot of talk about coal seam gassification underground. Basically as I understand it they would take played out coal bed methane wells and inject a mixture of oxygen and high temperature steam. The oxygen would burn the coal and the heat would break down the steam into hydrogen gas and oxygen that would also burn coal. Out the other end a recovery well would extract hydrogen and carbon monoxide with some carbon dioxide and water vapor. This mix would feed into a synfuel plant to be converted into methane or liquid fuels.

There was a proposal for one of those up in mid Michigan in the Aughts, aparently the coal there is in thin layers so it is more expensive to mine than it is worth when competing with really thick coal beds in the western states, but when th 2008 crash happenned everything went quiet.

Are these just pie in the sky ideas or is there a real possibillity these things could be money makers and get built?
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Re: Underground Coal Gassification

Unread postby Subjectivist » Tue 25 Mar 2014, 16:45:19

AP reported monday that an Australian company wants to use underground coal gasification in Wyoming.
The Wyoming Department of Environmental Quality supported the reclassification. Then in January, EPA officials told the state agency it needed to hold a public hearing and collect public comments on the proposal before the EPA would consider granting the change.

The hearing is set for 4-7 p.m. Wednesday at the public library in Wright.

Company officials didn’t return messages Monday seeking comment, but a group that successfully appealed the state Environmental Quality Council to review the project last fall said it remains opposed to the aquifer classification.

“We believe it would be illegal for DEQ to issue an aquifer exemption in this case, because the aquifer is good quality water that could be a future source of drinking water,” Shannon Anderson with the Powder River Basin Resource Council said Monday.

Department spokesman Keith Guille said by email the ultimate decision on the aquifer is up to the EPA, but the company has met all criteria for granting reclassification. Gov. Matt Mead spokesman Renny MacKay said the governor has met with Linc Energy officials and is following the project with interest, as it could add value to Wyoming’s coal.

Linc Energy has experimented with underground gasification in Australia but the project would be the first of its kind in Wyoming in several decades. The Lawrence Livermore National Laboratory experimented with underground coal gasification in the basin in three phases in 1976, 1977 and 1979. The Hoe Creek project gasified some 6,500 tons of coal.

Testing later revealed the project contaminated the site with substances including benzene, toluene and ethylbenzene, requiring more than $10 million to clean up.

More at the link.

http://p.washingtontimes.com/news/2014/ ... z2x0cDgZ24
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Re: Underground Coal Gassification

Unread postby Subjectivist » Wed 26 Mar 2014, 10:43:42

Hey Rockman ( jumping up and down waving for attention) Over Here!!
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Re: Underground Coal Gassification

Unread postby Tanada » Fri 28 Mar 2014, 06:23:22

My younger brother worked for a while in a Gasification plant in Indiana. They didn't use an underground system, they put petcoke and hazardous chemical waste in a retort and broke them down by burning in pure oxygen, then fed the resulting Carbon Monoxide and Hydrogen through catalysts to make synthetic diesel fuel in a variation of the Haber-Bosch process. I suppose underground coal gasification would work the same way, average coal in America is 50-50 Carbon to Hydrogen chemically so burning it in Oxygen would give you Carbon Dioxide and Water Vapor for low temperatures and Carbon Monoxide mixed with Hydrogen gas for high temperatures. By controlling the Oxygen flow in and gas draw out the production well you could control the temperature of the burning. Injecting steam would be the same basic process many cities used to produce 'water gas' before 'natural gas' became so easily available.

Early last century many cities used the 'water gas' process where they would alternate blowing air through a combustion chamber of burning coal/coke with blowing steam through the embers once the fire was hot enough. The air gasses would be routed to boil water to make the steam, then out exhaust stacks during the burning phase, and the output from the steam would be a mixture of Carbon Monoxide and Hydrogen gas that would be put through the city gas network. They had to cycle back and forth between the two phases because breaking Water Vapor and Carbon down into Carbon Monoxide and Hydrogen is endothermic, it robs heat from the white hot coal/coke bed. By injecting pure oxygen along with the steam this is avoided and the process is continuous, but getting the oxygen to do this is an energy cost.

I used to think we would go back to using 'water gas' because natural gas supplies were shrinking in lock step with oil, but fracking and shale gas are a cheaper alternative so I no longer expect that to happen. A country like China that has a lot of uneconomic coal seams and not a lot of Natural Gas potential on the other hand might use underground gasification to produce ample 'water gas' to do all sorts of things, both as chemical feed stocks and as fuel.
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Re: Underground Coal Gassification

Unread postby Subjectivist » Fri 28 Mar 2014, 14:12:02

http://youtu.be/TDeLZ7iWSgU

The UK already has issued permits for 18 deep coal seam gassification projects, so aparently this is going forward quickly in Europe even as it slowly advances in America.
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Re: Underground Coal Gassification

Unread postby Tanada » Sat 29 Mar 2014, 22:14:38

Does anyone know what it costs per BTU to produce this kind of In Situ gasified coal? The reason I ask is if the UK is approving these in rapid fashion, which the above video on YouTube certainly implies, then putting a underground gassifier program in place and using the produced gas to fuel a combined cycle gas turbine electric plant would be a very cheap way to conserve natural gas for purposes other than electricity production. The video outright says that gassified coal is much less expensive than mined coal, which in turn is much cheaper natural gas. Saying 'its much cheaper' doesn't really mean much coming from an advocate or a politician, I prefer hard numbers.
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Re: Underground Coal Gassification

Unread postby ROCKMAN » Sun 30 Mar 2014, 11:28:48

Given the current debate over frac'ng shales in the UK this could be of interest:

"Current Status: There are now signs that current issues relating to green house emissions and global price increases in gas are generating higher levels of interest in UCG and in 2009 and 2010 the Authority received applications for, and granted, some 14 conditional near offshore UCG licences to companies, keen to pursue the technology further in Great Britain. These conditional licences enable prospective operators to secure the rights to the coal while projects are developed but do not permit UCG operations to commence until all other rights and permissions are in place."
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Re: Underground Coal Gassification

Unread postby Subjectivist » Sun 30 Mar 2014, 13:09:33

ROCKMAN wrote:Given the current debate over frac'ng shales in the UK this could be of interest:

"Current Status: There are now signs that current issues relating to green house emissions and global price increases in gas are generating higher levels of interest in UCG and in 2009 and 2010 the Authority received applications for, and granted, some 14 conditional near offshore UCG licences to companies, keen to pursue the technology further in Great Britain. These conditional licences enable prospective operators to secure the rights to the coal while projects are developed but do not permit UCG operations to commence until all other rights and permissions are in place."

Coal mining in the UK has a very long tradition behind it, such tht they have been trying to figure out how to safely extract subsea coal for many decades.

Meanhile on this side of the Atlantic
Even hydrocarbon-rich Canada is in the game, with its soon-to-be-completed $1.5 bn Swan Hills Synfuels project in Alberta. This facility will exploit an otherwise inaccessible coal seam almost a mile deep, and utilize the gas in a 300 MW power plant, at costs that are said to be “very competitive.” Following on the heels of a successful demonstration project in 2009, the new facility is expected to start delivering gas in 2015. http://swanhills-synfuels.com The project will also capture over 1.3 million tonnes of CO2 each year, to be utilized for enhanced oil recovery.

With shale gas still very cheap in North America, Underground Coal Gasification may not make major progress on this continent anytime soon. But here’s the thing: ten years ago, we didn’t put much stock in the future of shale gas. Meanwhile, the global coal resource is enormous. Natural gas is a lot more expensive in other parts of the world. And lots of other countries are diligently running their experiments. Don’t be surprised if we hear a lot more about UGC in the years to come.
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Re: Underground Coal Gassification

Unread postby Tanada » Wed 25 Feb 2015, 14:21:09

This topic is producing lots of heat and light in the UK this week.

DESCRIBING underground coal gasification as “an imminent threat to the Forth” Dunfermline MSP Cara Hilton is calling for it to be stopped.

Cara Hilton MSP has broadly welcomed the Scottish Government's commitment to the moratorium on shale gas exploitation and coalbed methane in Scotland but she believes that Minister for Business, Energy and Tourism, Fergus Ewing should further use his powers and extend it to include UCG.

In a letter to the Minister, Cara Hilton MSP wrote that UCG is an “imminent threat”, with two companies preparing proposals in the Forth and Solway. She continued to state that both areas are vital to tourism, wildlife and commerce and as a result have come under strong opposition from leading organisations in such sectors.

Cara Hilton MSP said, “I know that licences for UCG are different from those for shale gas and coalbed methane and I fully support the idea that Scotland should be able to control licensing for all three techniques. However, I do not see this as a reason not to include UCG in the current moratorium when the risks are the same or even greater.

“I have called on Fergus Ewing to use the planning system and the environment licensing system to stop UCG in just the same way as he is using it to stop unconventional gas techniques.


Lots more at the link http://www.dunfermlinepress.com/news/ro ... the-forth/
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Re: Underground Coal Gassification

Unread postby vtsnowedin » Wed 25 Feb 2015, 17:47:59

I expect that as energy becomes more scarce we will devise ever more clever ways to extract the BTUs from all those small or otherwise uneconomical coal deposits we have passed by today. I would expect a lot of thin seams to be directionally drilled and fracked to extract the methane gas that is often present in coal seams. The process talked about above would also be used wherever it proves profitable. And then there are those ultra large tunneling machines we have all seen. I would expect smaller versions of those perhaps as small as one meter in diameter to be remotely controlled as they bore their way through and along thin coal seams sending their ground up coal back to the surface through shuttle robots following behind. They might work there way through a coal seam like worms working through a compost pile.
If your out under the North Sea and your robot miner gets stuck or otherwise lost you don't have to try to rescue it just send another one down to bore it's way out around the dead unit and onto more good coal.
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Re: Underground Coal Gasification Feasibility Report

Unread postby Subjectivist » Wed 24 Jun 2015, 23:19:50

A new report has just been released about current underground coal gasification in the UK.

http://youtu.be/0Mwl4SIQGyM
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Re: Underground Coal Gasification Feasibility Report

Unread postby ROCKMAN » Thu 25 Jun 2015, 10:46:34

sub - And here's the view of coal gasification by BBC News just one year ago:

"Not only does it make economic sense, but it allows China to exploit stranded coal deposits sitting thousands of kilometres from the country's main industrial centres. Transporting gas is, after all, a lot cheaper than transporting coal."

{In the case of England that's not an advantage since the source/consumption points are much closer to each other}

"Coal gasification can also help address local pollution problems that have in recent months brought parts of the country to a virtual standstill. But there are two big problems. First, coal gasification actually produces more CO2 than a traditional coal plant; so not only will China be using more coal, it will be doing so at a greater cost to the environment. As Laszlo Varro, head of gas, coal and power markets at the IEA, says: "Coal gasification is attractive from an economic and energy security perspective. "It can be a nice solution to local pollution, but its overall carbon intensity is worse than coal mining, so it is not attractive at all from a climate change point of view". The US has experimented with coal gasification in recent years Indeed a study by Duke University in the US suggests synthetic natural gas emits seven times more greenhouse gases than natural gas, and almost twice as much carbon as a coal plant.

The second problem is water use. Coal gasification is one of the more water-intensive forms of energy production, and large areas of China, particularly in the western parts of the country that would host new gasification plants, already suffer from water shortages. Mr Varro says a recent IEA report concluded that coal and coal gasification plants would use "quite a substantial portion of the available water in China".

{Maybe the boys at BBC have their heads up their asses but it doesn't sound like coal gasification (except for coal deposits under the N Sea) has any advantage over conventional coal mining and burning.}
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Re: Underground Coal Gasification Feasibility Report

Unread postby Tanada » Thu 25 Jun 2015, 11:33:35

IIRC and I freely admit I could be dead wrong on this, some 65 percent of all known coal seams are too deeply buried to dig up via surface or in the ground mining economically. However over half of that deep coal, or about 40 percent of all known coal, can be extracted via underground gasification is a very money making way.

I think of underground gasification for Coal to be much like horizontal drilling for old conventional fields. It is a way to get out the energy we couldn't get out before even though we knew all along right where it was buried.
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