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dpack

extremophiles

not here ,a long way down

i hope cab has seen these wee critters

they seem an awesome life form and perfectly suited to survive any surface changes
oldish chris

Quote:
They seem to use as little energy as possible to get by.
knew a bloke like that once.
Barefoot Andrew

Their diet is a bit limited.
A.
oldish chris

Their diet is a bit limited.
A.
what - coal rather than coke?
Shane

Surprised this is news, to be honest - we've known for decades about similar bugs that are found in oil reservoirs. Right pain in the bum, they are, as they produce hydrogen sulphide, which isn't the greatest of compounds to have to deal with.
Mistress Rose

Don't know if they are the same bugs, and I think the main point is that they were found so deep in the crust; far deeper than oil comes from. Hydrogen sulphide is, as you say, a right pain, and would image it gives you a lot of trouble.
dpack

iirc oil derived h2s is the source material for the world's oversupply of sulfur and the reason some "oil towns"are likely to be wiped out if there is a blowout of the well(i think there is a very deep extreme type well in one of the stans like that)and 9 workers died in denver

another place h2s is extra nasty is industrial pig units with the slurry under the floor,bugs make h2s ,h2s rots the electrics,spark ignites h2s and causes flashover to the straw ,resulting in roast pork in bulk.
Shane

iirc oil derived h2s is the source material for the world's oversupply of sulfur
Indeed - some of the Khazak fields are 30%+ H2S. There are pictures out there of the Khazak sulphur mountains. There's one on Kharg Island in Iran that can be seen quite easily if you get access to the right satellite photos, too.

another place h2s is extra nasty is industrial pig units with the slurry under the floor,bugs make h2s ,h2s rots the electrics,spark ignites h2s and causes flashover to the straw ,resulting in roast pork in bulk. You can get it in pits full of seawater, too, as the bugs that produce it are present in seawater and there's plenty of sulphates to reduce to H2S. Never get tempted to go into any pit full of stagnant seawater, as you may well not come out again. Fortunately, there's not too many of them in the UK.

Apologies for the slow response - been slumming it in Mauritius for a couple of weeks Wink
Mistress Rose

Nice for some. Very Happy

How do you get the hydrogen sulphide out of the oil, or is that not your problem?
oldish chris

Apologies for the slow response - been slumming it in Mauritius for a couple of weeks Wink that's no excuse, modern business people sit on the beach with their smart phones answering emails and all sorts.

(You can waterproof ones so that you can still do it whilst snorkeling round the reefs.)
Shane

Apologies for the slow response - been slumming it in Mauritius for a couple of weeks Wink that's no excuse, modern business people sit on the beach with their smart phones answering emails and all sorts.

(You can waterproof ones so that you can still do it whilst snorkeling round the reefs.)
Internet speed on Mauritius is so slow that it can't actually download emails. Unfortunately, this meant I had to go dinghy sailing, lounge by the pool and drink beer and cocktails instead.

Did actually rent a car and go see some of the island, too Wink

Oh - turns out that the iPhone 5S is pretty waterproof. Dropped mine in the sea and after a day of drying out it was working fine again. Laughing
Shane

Nice for some. Very Happy

How do you get the hydrogen sulphide out of the oil, or is that not your problem? It is exactly my problem, given that I design the equipment that does it!

Getting it out of the oil is easy - you just drop the pressure and it gases off with all the methane / ethane / propane / CO2. Getting it out of the gas afterwards, however, is another kettle of fish. It's normally done by using either media beds (think industrial-sized water filter cartridges), membranes or a recirculating amine solution, but all these processes need a lot of real estate and energy, and produce a nasty, nasty waste gas stream (that is normally burnt, as it's better to emit SO2 than H2S, even if Scandinavia's pine forests might not agree). If anyone's really, really interested I can give more details.
Mistress Rose

Yes, I am interested as I studied chemistry in my youth and am always interested in that sort of thing. Are there no emission regulations about sulphur dioxide where you are working, as in the UK and EU generally they are very strict? Shane

We are as strict on our facilities out here as we would be in the UK sector.

In the UK, you are required to show that your are using Best Available Techniques (BAT) and Best Environmental Practice (BEP). The suffix NEEC (Not Entailing Excessive Cost) has now been dropped, but still applies. When it comes to H2S, for a given production rate of oil or gas you have a given amount of sulphur that has to be removed from the process, and the only way to get rid of that on an industrial scale is to burn it (and produce SO2) or turn it into solid sulphur and stockpile it somewhere. The solids route isn't practical for many developments as there's only a limited market for it and any reasonably-sized, reasonably-sour project will generate huge quantities (a back-of-an-envelope calculation shows that a 200,000 barrel/day oil field with an H2S concentration of 500 parts per million will produce around 12 tonnes of H2S every day, so you can imagine how much you'd produce over 25 years of field life!).

Anyway, the summary is that as long as you minimise overall emissions of gas to atmosphere, the UK regulator will generally allow you to burn all of your sulphur, as the only alternatives are to build mountains of it onshore in the UK (imagine the outcry!), ship it to another country and pile it up there, or cancel the whole project.
Nick

When it's burnt, it's that all them there flaming towers that illuminate Middlesborough and such, or is it burnt usefully, to provide local heating, or power generation or something? dpack

i just had a thought re ucg ,i wonder how much of the sulfur will come out as h2s and how much as so2/3? as it is a "reduction flame burn" underground once the seam is hot i suspect a fair proportion will be as h2s rather than so2 until the product gas is burned in the power production process.

ps im trying to think of a good use or safe disposal method for a lot of sulfer. Rolling Eyes
Shane

When it's burnt, it's that all them there flaming towers that illuminate Middlesborough and such, or is it burnt usefully, to provide local heating, or power generation or something? The flaming towers (flares, we call 'em) are the waste gas that can't be captured and reused. In older facilities, there can be quite a bit as they used to just burn all the gas produced. Nowadays, we capture the gas, compress it, treat it and export it, with any flaring limited to the residual stuff that's too messy to deal with. The sulphurous waste stream from an H2S removal plant goes up the flare, with enough fuel gas supplied to ensure complete combustion.

Flares don't supply useful heat (as they are very low pressure and generally quite dirty flames), but nowadays it's standard practise to capture the heat from a turbine exhaust and use that for process heating (aero-derivative gas turbines are used to drive power generators and bigger compressors / pumps). On a modern oil / gas / chemical plant, you'll find most, if not all, process heat is supplied this way.
Shane

i just had a thought re ucg ,i wonder how much of the sulfur will come out as h2s and how much as so2/3? as it is a "reduction flame burn" underground once the seam is hot i suspect a fair proportion will be as h2s rather than so2 until the product gas is burned in the power production process.

ps im trying to think of a good use or safe disposal method for a lot of sulfer. Rolling Eyes Most of the sulphur will come out in whatever form it is trapped in the coal. The point of underground combustion is to provide enough heat to drive the vapours off the coal without burning them. It's the same process that you see in a log fire - if you look closely, the fire isn't actually on the wood itself, but is burning the vapours driven out of the wood by the heat. Only difference in underground gasification is that you drive the vapours off without setting fire to them. Mistress Rose

Thanks Shane, that is interesting. Seems as if making people burn use sulphur diesel rather defeats the object then, as the sulphur has to be burnt off somewhere else.

Fawley, which we can see from some local hills used to have lots of flares, but now only has one or two occasionally.
Nick

When it's burnt, it's that all them there flaming towers that illuminate Middlesborough and such, or is it burnt usefully, to provide local heating, or power generation or something? The flaming towers (flares, we call 'em) are the waste gas that can't be captured and reused. In older facilities, there can be quite a bit as they used to just burn all the gas produced. Nowadays, we capture the gas, compress it, treat it and export it, with any flaring limited to the residual stuff that's too messy to deal with. The sulphurous waste stream from an H2S removal plant goes up the flare, with enough fuel gas supplied to ensure complete combustion.

Flares don't supply useful heat (as they are very low pressure and generally quite dirty flames), but nowadays it's standard practise to capture the heat from a turbine exhaust and use that for process heating (aero-derivative gas turbines are used to drive power generators and bigger compressors / pumps). On a modern oil / gas / chemical plant, you'll find most, if not all, process heat is supplied this way.


Which is why the petrochemical industry is universally unpopular. Flares is such a bad name, dated and dull. FLAMING TOWERS OF DOOM is much betterer. Everyone would want those near them. It would keep zombies away and everything.

But yes, almost every modern plant I visit these days is reusing heat and water for various on site purposes, and cutting bills as a result. Amazing to see a whole plant run on rain water and waste pork scratchings. It's in Hull, so I suppose they have lots of both.
Shane

Thanks Shane, that is interesting. Seems as if making people burn use sulphur diesel rather defeats the object then, as the sulphur has to be burnt off somewhere else.
Yes and no. If you remove and burn at source, you can control (to some extent) where the nasty stuff goes. Better than every diesel engine in town pumping out SO2 straight into the lungs of babies.

Bit of a can of worms, really, the whole burn-at-source-or-burn-at-the-end-user thing. The only reason operators are under pressure to reduce the amount of gas they flare is to reduce the amount of gas that the UK has to import. It's nothing whatsoever to do with the environment, as the gas the operators are no longer burning gets burned in somebody's gas cooker or fire anyway, but it spins a good line for the government and the operating companies to pretend that it's all for the good of the planet.

Quote:
Fawley, which we can see from some local hills used to have lots of flares, but now only has one or two occasionally.

You'll see the same all over the country. Until quite recently, it was the norm to flare the gas from low pressure separators, as it's typically a reasonably small flow and historically wasn't worth recovering. Gives a nasty, sooty flame at a flare, so by recapturing it and pumping it back into the process you can really make yourself look good. Everyone recaptures it now.

Found a few good articles/sites here, here (check the links on the right) and here (this one downloads a pdf) that might be worth a read.
Mistress Rose

Thanks, I will try to have a look at them.
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