The Oil Drum

Some recent posts have dealt with coal production, so for a change I thought I would return to oil, for a couple of techie talks. It seems particularly relevant since the discussion has returned to the Canadian Oil Sands again, and the oil that is coming from them. But before getting there what I wanted to talk about was the differences that exist in what to some folk is just "crude oil," with the assumption that it is all the same, In writing about coal, it was fairly simple to show that the different stages of coal as it changes from peat to anthracite, mean that you get different amounts of energy from it, and it can be extracted with differing amounts of energy. The fact that there is a fair bit of difference in crude oils is not always as easily understood.

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.