Last week I wrote about the SAGD process and how it is used to extract the heavy oil/bitumen from the oil sands up in Alberta. What I will write about this week is the more general topic of In Situ ("in place") Combustion. I’ll talk about In Situ production as it relates to coal this week. Perhaps next week I'll talk about Toe to Heel Air Injection (THAI), a form of In Situ production which is being tested for use in the oil sands.

This is one in a series of weekly tech talk posts that deal with the technologies of conventional fossil fuel recovery. They are relatively short and so the descriptions are not provided in detail, rather they are meant so that you can understand some of the complexity of the process, and that it is not always easy.

This is one of a series of Sunday tech talks.

The movie Avatar gets the mining bit wrong. And not by just a little – but then us villains are rarely understood, so what should we expect? OK so what is a popular, nay perhaps even genre changing movie got to do with technical talks about fossil fuel production? Well, fairly early in the movie it is made clear that the sole purpose for the plot is to mine “unobtainium” which is a mineral with all sorts of value. Now I’m not going to give away much of what goes on in this movie (and I agree with most of that review by the way) but the fallacy over how they mine the deposits on the planet is one of the lessons learned from the mining of the oil sands in Alberta, which is actually what I want to discuss a little today. In the movie they use a variation on a bucket wheel excavator – which in today’s world looks like this:

In this series of tech talks, I have been writing about the progress of crude oil as it passes from the reservoir up through the production casing, and out to the GOSP, where water, oil, natural gas, sand and sulfur products can be separated. The example video that I referred to last week dealt with treating Canadian Oil Sands, and the oil that is coming from them.

What I want to talk about today is 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 is fairly simple to show that the different stages of coal as it changes from peat to anthracite. This means 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.

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.

To the uninitiated the thought of a gas or oil well is one where a pipe goes down into the ground, and out of it flows either a steady stream of oil or natural gas, that is fed straight into a pipeline and then delivered to them (often at what they consider to be an outrageous price) with no further treatment. Or the crude oil that comes out runs straight over to a refinery where (with minimum effort and maximum profit) it is transformed into the gasoline or diesel fuel that they must then again buy at great cost in order to drive in to the liquor store to buy some beer.*

The reality of oil and gas production is considerably different, and fluid that comes out of the well is not the ideal that the uninitiated imagines. So today’s topic will deal with the initial separation of a couple of the parts. This is a part of a series of tech talks that I write on Sundays about various aspects of fossil fuel production. It is a relatively simplistic explanation which seems to fit most folks needs, though it also has considerable help from those with more technical knowledge who add comments.