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July 09, 2004

Oil is blood (Reprise) 

"No war for oil!" and "No bloooood for Oiiiiiil!" are two of the most common slogans of the anti-war pack. I can see two main underlying assumptions behind these statements. First, oil is not that important, it's a kind of luxury good we don't really need, and any use of force to secure it are only another demonstration of the essentially evil nature of western white capitalists and blah bla blah...
Second, if we really need it, we need much less that the actual usage: just go downtonwn by bicycle or bus, and we'll cut oil consumption by an important fraction.

Let's examine, even superficially, the role of oil in the actual world economy, then.

Oil has three main uses: for energy production, as fuel, and as chemical feedstock.


Energy production

A comprehnsive review of the energy use of oil is published annually by British Petroleum. I strongly suggest to take some time to read the documents, because it's very instructive.
BP uses the term "primary energy", which includes electricity generation and fuel usage. In accordance, I'll use the term "energy" to indicate this primary energy, and electricity for this special case.
In 2003, the world's total (averaged) oil consumption (PDF file) for energy uses was 78 112 000 barrels per day (1 barrell = 136.4 kg). The shares are 30.1% for North America, 25.8% for Europe and Eurasia (ex URSS) and 28.8% for Asia Pacific. Central-south America reaches just a skimpy 6%.
The fraction of energy produced from oil ranges from 30% in Europe and Eurasia to 50% of Middle East, with North America at 40%. The other main sources are coal and natural gas - which is often associated geographically with oil. Renewable sources account for around 11% of the total energy production wordlwide.

Oil is an optimal fuel for power stations, because it is easy to pump, measure and convey a liquid from the tanks to the burner; it leaves much less ashes than coal and produces less CO2 per KW than coal.
Without oil, it would still be possible to generate energy from coal (which is hated by environmentalists), but the construction or reconversion of power plants is not something that can be done in six months. Differently from oil, the major reserves of coal are in Europe-Eurasia, Asia Pacific and North America, while Middle East has virtually no coal.
A non-fossil energy source, with huge capabilities, is nuclear energy. But only mentioning nuclear power stations causes, in environmentalists, hysterical crises, epilepsy attacks, temporary (although sometimes permanent) cessation of rational thinking, and other minor symptoms.


Fuel use

In a refinery, usually the first operation is crude oil fractional distillation (topping), to produce a gas fraction and different liquid fractions, with different boiling point range, and a heavy residue (refinery processes require great amounts of heat and energy, thus the gas fraction and residue are often burnt on-site to produce heat and/or steam). A certain amount of the light fractions (naphta) goes to the petrochemical route, while the rest undergoes more treatments and comes out as fuels: gasoline, kerosene, diesel oil and fuel oil. The amount of processing can be minimal - just topping in case of fuels produced for local use in remote oil fields, but usually fuels are desulphurised (the bulk of sulphur is produced in this way, not mined naymore) and treated in other ways to improve their performance and other carachteristics. Racing and high-performance gasolines are an accurate blend of hydrocarbons produced by holigomerization of ethylene: this amount of processing makes them expensive, but also very performing. Fuels are used to power motorbikes, cars, trucks (lorries, in the ol' Britain), trains, airplanes, ships, construction and earth-moving machines, electricity generators, heating systems, furnaces, stoves, steam generators etc (although the cleaner natural gas is gaining points for many applications). Besides the obvious contruction and earth-moving machinery, also transportation is fundamental in shaping our world: raw materials must be delivered to the factories, and the end products to the wholesalers and then retailers. Managers, but also engineers and technicians need to travel in order to meet each other to discuss projects, reach agreements and do business. Goods travel mainly by ship, train and lorry, while people travel by train and airplane - but the importance of cargo plane is great and growing (the plane is by far the quickest way to deliver goods at long distance). At least in the developed world, there are no more vehicles powered by coal or wood, or gas generated from those fuels. (Well, this is not exactly true, because coal can be gasified and the syngas used to synthetize hydrocarbons - as in the South African SASOL process; but the SASOL is a sophisticated chemical engineering creation, not a makeshift solution). Instead, there are nuclear-powered military ships and submarines. Wood and coal are still extensively used for heating and cooking, especially in developing countries and rural areas. And the real Italian pizza oven is wooden-fired.

Thus far, it should be clear that oil is almost insostituible (at least in short times) as a source of energy.


Feedstock use

Oil is also the first raw material for the production of organic chemicals. How? Through petrochemistry.
We left some of our naphta taking the petrochemical route: this begins with steam cracking, which produces mainly the reactive gases ethylene and propylene.
Other useful substances, like benzene and dienes, are produced with different reactions from the same feed (or from ethylene/propylene with other reactions - the specific choice depends greatly from considerations out of the strictly chemical realm). Methanol is typically synthetized from methane or natural gas via steam reforming and synthesis gas, a mixture of carbon oxide and hydrogen useful for many reactions. With these chemicals at disposition (and a few more important ones), everyting goes downhill: in hundreds of different reactions and processes (The most comprehensive encyclopedia of chemical technolgy takes 24 volumes and thousands of pages. Kirk-Othmer)
these fundamental chemicals can be transformed in an almost unbelievable variety of chemicals which constitute the objects and products we extensively use in our everyday life. Not only plastics, but I daresay that most carbon-containing (organic) compound derives from oil - except a few materials of natural or other origin. See here for more explanations and a nice interactive flowchart.

Update 12/07: Shees, if I'm slack... let's finally give some facts and figures about petrochemical industry. Europe only, produced in 2003 produced 20 685 000 tons of ethylene; 14 666 000 t of propylene; 2 130 000 t of butadiene (used mainly to produce rubber) and a good 15 000 000 t of aromatics. On a global scale, North America produces 41% of world ethylene; 38% of propylene and 33% of benzene. Europe's shares are respectively 29%, 34% and 30%. Asia comes third, with 25%, 28% and 34% (Calculations mine, from IPIF data). South America gives only minor contributions.

From this brief overview, it should be clear that our present world is shaped by and modelled on the availability of chemicals and fuels, which in turn are obtained - although sometimes with a long and tortuous route - from oil. Oil is the lifeblood of our economy and civilization. A sudden relevant cut of production or shipment would have catastrophic effects - on the whole world, not only the developed countries.

So, what is acceptable to do in order to keep the oil flowing?
I'll try to explore this realm (far more slippery and insidious than my well-known industrial chemistry) in the next article: The Ethics of Oil.

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