Getting gas from Crude
Posted by Heading Out on March 13, 2006 - 2:19am
Topic: Supply/Production
Tags: crude oil, distillation, fractioning column, oil, refining, tech talk [list all tags]
This then will be a relatively simplistic look at the different potential hydrocarbons that might make up a crude oil, and how we can get them apart. I'll post next time on how we can break the separated flows into other products. This, then, is a short techie talk in the oil production series, earlier posts in which are given at the end of the post.
Crude oil is made up of a mixture of hydro-carbons, which are the different ways in which carbon and hydrogen can combine, starting with such simple compounds as methane (CH4) and progressing to more complex ones with greater numbers of carbon atoms. Oils from different places have different combinations of the major constituents, for example, this is from Kuwait. Because they are fluids mixed together, it is not very easy to separate out the different valuable parts (known as fractions) by a mechanical means. However if you heat up the crude oil blend, then it will vaporize.
As the combined vapors from the heated crude enter at the bottom of the tall tower (called a column) they pass up through different trays that are placed at set heights up the column. When the gas reaches a tray it passes up through it into a bubble cap, this is a cover over the hole that pushes the gas down so that it has to bubble up through the liquid that has already condensed onto that tray.
The liquids in each tray, as the vapor rises higher in the column, are kept at lower temperatures, so that the heavier oils, that condense at a higher temperature, will condense lower down the column. As the lighter vapor rises through successive trays, the temperature of the liquids drops, and lighter fractions of the oil also begin to condense out, until the very lightest are collected at the top, still as gas, and fed on to a cooler. The liquids then drain, either back down to a lower tray, or through a side-draw pipe that taps the fluid from the trays and takes it away for either further division or for storage and sale. A typical initial distillation might yield
Each year the EIA publishes its world distillation capacity which is the necessary part of getting from crude to useful product.
I will continue this next time, talking about the further stages in refining, and cracking of compounds to break them into lighter fractions, so that the next product from a refinery might at the end, look something like this (courtesy of the EIA).
This is part of an ongoing weekend series on technical aspects of oilwell (and natural gas) drilling. Previous posts can be found at::
the drill
using mud
the derrick
the casing
pressure control
completing the well
flow to the well
working with carbonates
spacing your well
directional drilling 1
directional drilling 2
types of offshore drilling rigs
coalbed methane
workover rigs
Hydrofracing a well
well logging
seismic surveying
gravimetric surveying
carbon dioxide EOR
As ever, if this is not clear, or if there is disagreement then please feel free to post, and I will try and respond.
the problem was they could not make it fast enough, it's been theorized that if they were able to produce enough if it they would of lasted long enough to bring jets and the other weapons they had in the wings online.
"The Haber process now produces 500 million tons of artificial fertilizer per year, mostly in the form of anhydrous ammonia, ammonium nitrate, and urea. 1% of the world's energy supply is consumed in the manufacturing of that fertilizer (Science 297(1654), Sep 2002). That fertilizer is responsible for sustaining 40% of the Earth's population."
http://en.wikipedia.org/wiki/Haber_process
Uses natural gas.
Estimated to have roughly doubled the amount of biologically available nitrogen on the planet.
Interestingly, the Germans had plenty of ethanol and liquid oxygen to fuel the V-2s until very close to the end of the war.
The answer is: he shot down 23 Messerschmidts.
What was the question? Why was Hans Schmidt kicked out of the Luftwaffe?
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I get blank stares when I tell it to young people.
Took me some time to understand the humor though.
in 1944. The German armed forces were still chronically short of all liquid fuels. Most evident in the battle of the Ardennes when even the crack units involved in the attack were not equipped with enough fuel to reach the Meuse River. They were supposed to capture it along the way. Most German tanks just ran out of fuel and were abandoned rather than lost to US action.
F-T is very inefficient. But when desperate and have access to slave labour then you will try anything.
My recollection from Speer's memoirs is that oil production from coal peaked higher and later than you state, but Speer could have been wrong, or (Yes, it has happened a couple of times.) my memory could be in error.
The Germans were always chronically short of gas, made much worse after the loss of the Rumanian Oil fields.
In fact , perhaps The Second World War should really be called 'The First Oil War'. Japan and Germany both
had the same problems. Anyway, thats history. I believe that South Africa has made the best shot at the
F-T Process during the years when they were under economic sanctions. But again, more I think from desperation than economics.
I suspect you might have slipped a decimal place there, and that it should really be 160,000 barrels per day instead of 16,000.
While I don't have the German synthetic fuel production for 1944, one of my military books cites a 1940 production of 4.25 million metric tons. That would translate into an equivalent average daily production rate of roughly 78,000 barrels per day. So, if the Germans ramped up production to reach a maximum in 1944, that would constitute about a doubling over the 1940 production level, and therefore indicating that 160,000 barrels per day is very likely the correct number.
While it took a tremendous effort on the part of the Germans to attain this level of synthetic fuel production, by modern standards it's pretty tiny, about the output of a medium-size oil refinery.
I bring this up not to nit pick about German production numbers but to perhaps add some perspective on what a major undertaking it will be to get even several million barrels per day of additional coal-to-liquid production.
pay attention Mudlogger.
What I am getting at here is that in regard to Peak Oil, you are only as good as your engineers, your geologists, and your managers. The focus on equipment limitations, etc. is valid, but I think in the real world often the most serious bottleneck is the shortage of highest quality well-trained talent.
The U.S. impending shortage of steel is scary. To me ten times scarier is our shortage of engineers.
Right now on CPSAN, Arlen Specter is running a Senate Panel investigating the rising prices of Natural Gas (NG).
Their solution?
Pass laws.
The law shalt provide.
That is even more profound than the "free markets" providing.
http://www.c-span.org/
Will they arrest and bring to trial Mother Nature when she refuses to comply?
Are you writing the script and getting ready to videotape it?
Title: "Munity of the Oil Bounty"
Mother Nature is put on trial for refusing to put out anymore.
Casting:
Role of Mother Nature: Sharon Stone (Whata ya going to do, arrest me for running out of lube?)
Captain Blight: Jack Nicholson (We don't want to hear the TRUTH. We can't handle the TRUTH!)
Young Ensign Christensen: Russel Crowe (We are masters and commanders of our own destiny. We got to turn the ship of state around! Call it mutiny if you must.)
I am sure that the UK have passed just as stupid laws in fairness.
The best one is still the "monkey trial" of Creationism vs. Evolution.
Next one will be stem cells.
With so much of our manufacturing being outsourced, maybe we really don't need as many engineers as we used to (('m talking here in the aggregate, shortages or gluts in certain highly specialized areas notwithstanding).
Even if there really IS a shortage, no problemo - we just import more engineers from India, Pakistan, China, or wherever. Engineering has become fungible, like almost everything else.
Regarding steel, I was not aware that there is an actual steel shortage in the US, though heavy manufacturing is not something I follow anymore. We actually use far less steel than we used to. If I recall correctly, the peak year for US steel production was 1957 (big cars and a construction boom). One must also keep in mind that a large fraction of steel is recycled. I don't recall the actual figures, but a surprisingly high percentage of the steel in a junked car becomes new steel. I would think we're going to run out of energy to smelt, shape and manufacture steel goods long before we run out of iron ore + recyclable scrap.
We could get iron by using our baseload power plants to electrolyse sulfide ores for metal, yielding electrolytic iron for feed for electric heated minimills, and also produce plenty of byproduct metals like copper, nickel, PGMs, zinc, lead, silver, gold, etc. This would not be economic at present prices. But if the dollar dropped 90%...
Gasoline is way more complicated than most people know or want to know or need to know. Best people to talk to on this topic are the people actually in the business at the wholesale level; buy the guy a couple of drinks and he'll probably tell you a tale of woe (related to boutique blends) and way more than you wanted to know. What I find fascinating is the way prices are set in reality--and it has almost nothing to do with what is written in economics textbooks that are regarded as gospel truth by undergraduates.
Volatility matters since the evaporated portion contains a lot of VOCs (volatile organic compounds) that contribute to air pollution, and thus are controlled in most locations. Volatility is why most pumps now have the hood on the nozzle to capture the vapors as you fill the tank.
The Federal blend formula requires 7 RVP in summer and 13 RVP in winter, but most states set their own blend constraints, sometimes county to county depending on the air pollution situation. In California, we have the California Air Resources Board (CARB) formula requiring 7 RVP in summer and 10 RVP in winter (because of our mild winters and bad air pollution).
Blending to RVP (and octane, and sulfur, and all the other simultaneous requirements of final gasoline) is tricky. For example, butane gives you a very high octane rating so is good for the octane target, but it is very volatile, so it is bad for the RVP. Refiners have to change their blending recipe between summer and winter to achieve these targets, sometimes creating shortages or surpluses of particular fractions (such as pentanes) in the refinery.
As might be expected you get a lot more naphtha from the distillation process than you can possibly use. In Saudi Arabia they use it, occasionally, as boiler fuel. I worked for awhile at the Gazland Power Plant, just about five miles west of Ras Tanura, in Saudi Arabia. About once a month, for a day or so we would use naphtha as a fuel. Occasionally we would use raw crude as well but most of the time we used natural gas. The plant had both gas and oil burners or injectors in the same boilers and you could switch from one to the other without ever losing your flame.
However in Saudi Arabia today, most of the naphtha is simply injected back into the wells to help keep the pressure up. At least that is what my son tells me. He has been in Saudi, working for Aramco, since 1991.
Note: Technically gasoline is sometimes considered naphtha, however as the term is normally used, it is the light colorless fluid that dry-cleaners and Zippo lighters used. It is also used in many manufacturing processes as well, blending naphtha with heavier compounds to make various household compounds. Gasoline has 7 to 9 carbon atoms and anything from 6 to 11 carbon atoms is considered naphtha.
http://www.gcsechemistry.com/o5.htm
The biggest problem with naptha, I read, is the octane (35-40). It is complicated, but one of the functions of a catalytic reformer is to convert naptha into higher-octance gasoline blending components. The transformation isn't really adding carbon atoms, but rather the structure of the molecules are changed.
It yields net hydrogen and is called dehydrogenation.
The problem is making shorter ones out of longer ones. The basic issue is that you have to ADD hydrogen. Refineries can do this and the more facility they have the higher the capital investment. If we had a great source of cheap hydrogen or cheap energy, we could turn coal into gasoline.
As to octane ratings for naptha, remember that pure octane is 100 octane, by definition (research and motor.) Shorter strings have lower octane rating until you get methane or ethane when it turns back up (methane is 120 octane?)
Hence, a naptha that has a lower vapor pressure than gasoline has an octane rating lower than standard gasoline.
On the other end, longer chains do not vaporize easily enough so are used for diesel fuel which burns as a mist.
The refiner will adjust his mix of output products based on his feedstocks, product market demands and prices, and capital investments.
http://en.wikipedia.org/wiki/Naptha
My understanding it is more of a feedstock for Petrochemicals mainly olefins but not exclusively
How can we have "Switch Grass for Victory!" if the wildfires keep burning the grass? http://www.cnn.com/2006/US/03/13/wildfires.ap/index.html
The Scuderi Group is an engine development company currently building an Air-Hybrid Engine which it claims will be to be the world's most fuel efficient internal combustion engine. Currently in production at Southwest Research in San Antonio, Texas, it is claimed that the Scuderi Air-Hybrid Engine will allow diesel and gasoline automobiles, commercial vehicles and other applications powered by internal combustion engines to be 60 percent fuel efficient (compared to today's 33 percent), http://www.gizmag.com/go/5318/
Researchers at GE say they've come up with a prototype version of an easy-to-manufacture apparatus that they believe could lead to a commercial machine able to produce hydrogen via electrolysis for about $3 per kilogram, down from today's $8 per kilogram. http://www.techreview.com/BizTech-R&D/wtr_16523,295,p1.html Hot Dog! They will be ready for production "in a few years" Dang!
Solar concentrator company is claiming about $3.50 per PV watt...Not bad! http://www.parc.com/about/pressroom/news/2006-02-16-solfocus.html
Iran threatened Saturday to use oil as a weapon if the UN Security Council imposes sanctions over its nuclear program. http://www.canada.com/topics/news/world/story.html?id=35f56a71-53ee-48d9-b8f0-38dccfec22c0&k=210 72 Oh, wait a minute, we meant that we will use oil as a "what you ma call it..." http://today.reuters.co.uk/news/newsArticle.aspx?type=topNews&storyID=2006-03-12T071331Z_01_OLI2 25315_RTRUKOC_0_UK-NUCLEAR-IRAN-OIL.xml On the other hand, "Iran's Supreme National Security Council, which represents Iran in nuclear talks, has said Iran has no plans to play the oil card at present but could do so if "conditions change". Now lets see how the future's market responds yet again with instantaneous efficacy... My slow-moving inefficent self is buying a few more shares of XOM.
Generaly.
But not very good either. That amounts to a capital cost of $3,500 per kilowatt capacity. A big coal or nuke should cost less that $2,000 per kW.
The capacity factor for solar is rarely 20% while the nuclear industry is averaging over 90% so a kW of nuclear capacity produces 4.5X the kW-hours of a kW of solar PV.
Adding fuel and O&M for nuclear of 1.5 cents per kW-hr and ignoring PV maintenance makes solar PV electricity about 7 times more expensive than nuclear power.....IF this claim is true and comes to eventual realization.