Showing posts with label sorbent. Show all posts
Showing posts with label sorbent. Show all posts

Thursday, June 25, 2009

CO2 Removal

This is interesting as it provides a viable option not presently available. Not necessarily wonderful but not so problematic either. You have a present day coal plant and a retrofit reduces your output but puts the CO2 in a form that can be dealt with. It may still be expensive but it has leveled the playing field between you and a Greenfield power plant.

All that matters because financing new plants will absorb most available capital for the next few years and total rebuilds are typically a lousy financial option.

Of course, we expect most capital to flow into alternative systems and simply prolonging the life of these plants may be the only option. This certainly makes it possible to manage the problem.

Of course CO2 disposal is still the real problem, but I assume this process naturally separates out the nitrogen so it is now as efficient as is possible making geological storage much more attractive. Also modest compression reduces the volume hugely and there are plenty of natural geological traps to exploit. Just keep drilling deeper.

I do not know if it will be much utilized, but well funded facilities will certainly look at this option, just for political reasons. Now if we could only get them to use the chlorine quench method to strip out the Sox and NOx and particulates we would have power plant and metal smelters all running completely clean. It is actually possible, since efficient CO2 removal was the remaining difficulty.

In short, I now think it is possible to operate a thermal metal smelter or steel mill while efficiently capturing all the output gases and particulate and the heat energy while dumping only the nitrogen gas back into the atmosphere and perhaps minor residuals if that. It took about thirty tears to establish proper solutions and will now take just as long for commercial acceptance now that it can be done.

June 23, 2009

http://nextbigfuture.com/2009/06/co2-removal-from-atmosphere.html


Professor Klaus Lackner, Ewing-Worzel Professor of Geophysics in the Department of Earth and Environmental Engineering at Columbia University have developed a sorbent that is "close to the ideal," in that it uses a relatively small amount of energy to release the CO2 and is not prohibitively expensive.

"By the time we make liquid CO2 we have spent approximately 50 kilojoules [of electricity] per mole of CO2." Compare that, Lackner said, to the average power plant in the U.S. which produces one mole of CO2 with every 230 kilojoules of electricity.

"In other words, if we simply plugged our device in to the power grid to satisfy its energy needs, for every roughly 1000 kilograms [of carbon dioxide] we collected we would re-emit 200, so 800 we can chalk up as having been successful," he said.

The biggest cost was at the "back-end" of the collector, primarily the technology used to release the CO2 from the sorbent. He said for that reason, on a cost-basis, the "synthetic tree" could not compete with modern coal-fired power plants that are designed to release fewer carbon emissions than their older predecessors. But he said when compared to the cost of retro-fitting an existing coal plant, the "synthetic tree" becomes more viable.

"Each unit would take out a ton of CO2 a day -- which would be the amount of CO2 produced by 20 average automobiles in the U.S.A. And the cost of each unit would be about the cost of a Toyota. So that would mean if you added a five percent surcharge on automobile purchases that money could go to building units to remove the CO2 those vehicles are going to create."

The technology is not being developed as an alternative to the carbon capture and storage methods currently being tested for large-scale use on coal-fired power stations. He's targeting carbon that's already in the air