A miner issue

[Katman]

Can anyone explain this 'high pressured methane gas line' (supposedly pumping 800 litres of gas per second) to me?

From what I've read, methane gas is released from coal during the mining process but I wouldn't have thought it would be in a quantity or a manner that required a high pressure line to extract it.

[Winston001]

I asked that question the other night Doug. What the hell do they do with the coal? Some bloke on TV that has been mining all his working life said ...everything we use in our lives in either grown or mined. Now I know the PC I am currently typing did not grow in the garden or on a tree so it must be made from mined stuff?
Probably not coal. although, looking at it.....

Yes. Oil. Plastics, fertilisers, pharmaceuticals, a vast range of what we consider normal consumer products are made from oil.

Coal is one of the biggest energy (electricity) generating products in the world. Furthermore it is possible to produce gas and liquid fuels from coal as well as other organic hydrocarbon compounds. Very useful stuff, just not as concentrated and easy as oil.

[kevfromcoro]

Can anyone explain this 'high pressured methane gas line' (supposedly pumping 800 litres of gas per second) to me?

From what I've read, methane gas is released from coal during the mining process but I wouldn't have thought it would be in a quantity or a manner that required a high pressure line to extract it.

Yeah ,, somthing is not right here...

Why would they be pumping methane down into a coal mine..

Cant see them pumping it out..
Wouldnt be enough of it.
One would think..............

[Banditbandit]

I thought he meant that a pipeline that was pumping methane OUT of the mine had burst - and was therefore releasing the methane back out of the pipeline somewhere in the mine ...

[cromagnon]

Edit: Missed something, totally different thing.

[Katman]

I thought he meant that a pipeline that was pumping methane OUT of the mine had burst - and was therefore releasing the methane back out of the pipeline somewhere in the mine ...

I would have thought the methane would be vented through ventilation shafts or extracted using a normal extraction fan and ducting type system. I wouldn't have thought it would use a system capable of pumping 800 litres per second back into the mine.

[Banditbandit]

I would have thought the methane would be vented through ventilation shafts or extracted using a normal extraction fan and ducting type system. I wouldn't have thought it would use a system capable of pumping 800 litres per second back into the mine.

And I would have thought that if the electricity went out, whatever method they used would stop - no power no extractor fans ... probably just as bad ...

[avgas]

Ok, I had a chat to Dad. He's down at the Burt having a break.
His team is all still alive thankfully, likewise the other connel team is ok.
Quick look in here - and its KB as usual. Half arsed guess work at its best.
I don't think I will say too much here - as no doubt it will entail an argument - something I don't want to do on this argument.

But I will say this.
If everyone was on time, on schedule that day. Dead total would be 49. So there is a bit of a silver lining.

Coal dust is pretty much self combustible.
As for the methane thing - methane does go inert over 15% down there. Sadly this would definitely kill all involved..... But ideally you seal off, wait for the methane level to build up - oxy is burnt up.....fire dies.
Also if there is a fire in the coal seam it may not go out (http://en.wikipedia.org/wiki/Centralia,_Pennsylvania)

Ah you have got me waffling on again, making comments that will no doubt start arguments. And I have not even got to the fact the engineering drawings had separate entrance and exit tunnels.

Perhaps I should stay away from this thread. I am off to have a beer

[Katman]

Coal dust is pretty much self combustible.
As for the methane thing - methane does go inert over 15% down there. Sadly this would definitely kill all involved..... But ideally you seal off, wait for the methane level to build up - oxy is burnt up.....fire dies.
Also if there is a fire in the coal seam it may not go out (http://en.wikipedia.org/wiki/Centralia,_Pennsylvania)

So the "massive build up of methane" wouldn't have caused the explosion?

[marty]

interesting comparisons to be drawn (insofar as explosion/methane behaviour - not safety standards)

http://en.wikipedia.org/wiki/2007_Za..._mine_disaster

[neels]

And another explosion.

http://home.nzcity.co.nz/news/articl...945&fm=psp,tst

Hope the poor buggers went quickly with the first one, and hopefully it settles down enough to get them out for their families.

[Jantar]

History has a lot to tell us ...

In March 1896 the Brunner Mine, ......

The first miners to arrive on the scene ran into the mine, then had to be rescued themselves as they passed out from the gases ... (So much for "the best time to go into the mine is straight away" ...) .... ..

A lot has changed since 1896. Immediately following a methane explosion is still the safest time to enter the mine, with breathing apparatus. Without it the rescuers will be overcome by the hot poisoness gasses, mainly carbon monoxide. Following the explosion the methane has burnt up and it takes time to re-establish to an eplosive mixture, just like it takes time for your bike engine to expunge the exhaust gasses and refill with a fuel/air mix.

The men in the mine can only survive if they can get to a safe shelter within a few minutes of the initial explosion. There are such shelters in the Pike River mine, but there has been no communication from any of them, so it's a safe bet that no miners got there. Unfortunately, along with the methane, the oxygen has burnt up as well, and that is why the survivors (if any) have a very short time frame to get to one of the shelters with an air supply and phone.

A caveat, I have no coal mining experience at all. I do have underground experience at the Rangipo power station which is treated as a mine situation. I also had the task of writing the report on evacuation, fire fighting and rescue procedures for that station imediately following commisioning in 1986.

[Swoop]

Coal dust is pretty much self combustible.

Any fine dust is combustible. Look at flour mills for example.
Suspended in the air it is able to flash over and instantly burn, i.e. explosion.

[kevfromcoro]

Years ago i was working in a place were they make particle flooring..
the air was thick with dust....
Had an explosion one day.. blew the arse end of the factrory wall out..
Lucky there was no body injured......

From there i went to rangipo mine site.......
Spooky under ground...

[doc]

the oxygen has burnt up as well, and that is why the survivors (if any) have a very short time frame to get to one of the shelters with an air supply and phone.

I use to manage a Kiwifruit coolstore and CA store.
I know that in a controlled atmosphere store it is not possible to open the sealed door and climb to the top of 4 storage bins and grab a kiwifruit for firmness testing without taking a severe risk with your health. Less than 30 secs without oxygen and your in trouble.
Even doing it with BA gear you felt crook for the rest of the day.