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Pipe-dream meets reality
| Content Provider | Semantic Scholar |
|---|---|
| Author | Davidson, Sam Maitland, Geoffrey |
| Copyright Year | 2005 |
| Abstract | IMAGINE if we’d never struck oil. If there was no century-long history of technology and strategies for dealing with fossil fuels. If we were starting from scratch. Starting from first priniciples and using today’s technologies, and with current knowledge about the environment, how would we do it? It sounds like an abstract piece of thinking, but it’s one of the main tasks facing the Energy Futures Laboratory, a multidisciplinary research body recently launched at Imperial College,UK (see also news on p11). Combining the expertise of chemical, mechanical, systems and biochemical engineers with statisticians, social scientists, geologists, materials scientists and mathematicians, the Energy Futures Lab aims to predict how much energy mankind is going to need as the current century progresses, where it’s going to be needed, and how it’s to be generated. The research effort spans many types of power generation, including renewables like solar, wind and waves; the decommissioning of the current generation of nuclear reactors and safe handling and storage of their wastes, and the design and construction of their possible replacements; the various types of biomass and strategies for extracting more of the energy content of crops; the hydrogen economy, and how it will affect power grids; new strategies for distributing energy; and how to optimise the energy generation and consumption in the new cities currently being built and populated in China. Everybody agrees that the coming decades will see a much more diverse spectrum of electricity generation methods. However, today’s main energy source, hydrocarbons, is still likely to be one of, if not the, major contributor to the mix well into the 21st century. A great deal of oil, gas and coal has been extracted from reserves; but a great deal still remains. The problem is that it’s the easy reserves that have been recovered; the remaining hydrocarbons are in awkward locations, or in a form that is hard to recover and process. This is where the research of Geoffrey Maitland is focused. Professor of energy engineering at the Energy Futures Lab since September, Maitland was previously with Schlumberger, where his work focused on applying modern instrumentation and control techniques to oil wells. He is continuing this work at Imperial, while also setting up collaboration with other researchers to tackle the problems of recovery and utilisation of hydrocarbons. The first stage is to use modern sensors and instrumentation systems to see what is happening inside oil and gas wells, and then to use this information to improve the wells’ performance. “The industry has moved away from post-mortem logging and matching those measurements up with the models of the reservoir and the predictions, to trying to obtain a real-time view of what’s going on in there,” Maitland says. “Putting permanent sensors in the wells, and eventually into the reservoir itself, is the first step towards that.” This, he says, basically amounts to using technology which is well established in chemical plants – especially petrochemicals – and applying it in a much less ordered, and more arduous environment. The new generations of smaller, more advanced and cheaper sensors will allow this to happen, he says. This will allow redundancy to be built into the sensor packages, with large numbers of sensors being put in place within the well at any time, he says. The sorts of measurement that might be made include flow rates, and especially the thermophysical properties of the crude oil and gas. This will allow engineers to use what Maitland calls a “systems approach” to the wells. Oil is recovered by injecting another fluid, usually water but increasingly supercritical carbon dioxide, into the reservoir to push the oil out to a producing platform, but currently this is a rather random process, he says. “You wait at one well to see what happens as a result of injecting something a few kilometres away. You have an injection well that you can vary the pressure in, and a production well where you suck down on that pressure to produce your crude oil.” The next phase is to take the analogy to chemical plants a little further, by installing valves inside the well to divide it up into segments. The sensor systems will monitor the conditions inside each segment, providing information on the type of fluid flowing in the section and the stability of the flow. “If you start to produce water from one section, you can shut it off or change the injection strategy,” Maitland explains. “But what we’re trying to do is to enable people to make these decisions well before you start to produce water, because you’ll see the flow of oil is becoming unstable.” Maitland estimates that this type of technology is not too far away. “Many of the parts of the jigsaw are already in place, and we can expect to see it applied within the next decade or so, especially in wells which are approaching the late phase of their exploitation, such as in the North Sea and the Middle East,” he says. But the next phase of the research is much further off, and far more ambitious. When oil and gas are extracted from their subterranean resting places, they are under high pressure and at high temperature. They are transported through many kilometres of piping to the surface, where the pressure and temperature are reduced, then they are pumped to terminals and onward to processing sites – where, in order for them to be refined and converted into useful products, they are heated and pressurised. This, Maitland points out, is hardly an efficient use of resources. Why pay, and use valuable fuel, to put energy into a substance that already possesses that energy in its natural state? And why leave all those kilometres of conduit as merely a transport system? “What we have,” Maitland says, “is a |
| Starting Page | 40 |
| Ending Page | 41 |
| Page Count | 2 |
| File Format | PDF HTM / HTML |
| Alternate Webpage(s) | https://www.imperial.ac.uk/people/r.bryan/document/2342/tce2005/?tce2005.pdf= |
| Language | English |
| Access Restriction | Open |
| Content Type | Text |
| Resource Type | Article |
