Carbon Capture and Storage...CCS

I have always been skeptical of this approach to reducing carbon emissions, because it has to obey the laws of thermodynamics, and hence will be very expensive to carry out, even with unique carbon capture schemes. But if one gets right to the heart of doing it as efficiently as thermodynamically possible...well maybe it will be a viable solution for reducing carbon emissions, especially from coal fired power plants.

So here is a link to the best lead I have seen to achieve this:
ATMI-Brightblack

The Allam Cycle - An efficient way to Capture and Store CO2 (aka CCS)

Thermodynamic principals work strongly against the efficient (read economic) capture and storage of CO2 from conventional fossil fuel power plants. Dilution of the CO2 by nitrogen in the flue gas from the air used for combustion is a primary issue.

But, if we can burn the carbon containing fuels with pure oxygen, then the effluent is mostly CO2 and water vapor, which can be easily separated, and the CO2 compressed for efficient, and hopefully safe, underground storage.

So see what you think about the Allam Cycle. I am glad to see a major project going forward to determine future economic feasibility. Technology can do a lot, but technology can not override the laws of thermodynamics.

Carbon Capture and Storage (CCS) - An IEEE Perspective

No question, creating enough alternative energy sources to totally replace fossil fuel sources will take a considerable time. My estimate is more than 100 years. So in the meantime, as we continue to burn fossil fuels, can we offset some of the damage by capturing the carbon released and storing it indefinitely???

Well unfortunately, the technology to do so economically has not yet been developed, and does not appear easy to develop, based on many studies and pilot plant tests. I personally have never given it a chance, but now in this IEEE article, Inside the World's Largest Carbon Capture Test Facility, I see some rays of hope.

First, on a thermodynamic "theoretically perfect basis", carbon can be captured for only an 8% cost of the energy produced by a coal fired power plant. Still, the best pilot plant experience to date is a 25% cost, and that has yet to be done commercially.

So now, I am a tad less pessimistic than I used to be, and I most certainly hope for some for some major breakthroughs.

Note: The IEEE (they like to be referred to as "I Triple E") is a very large international engineering organization. You can read much more about them on their site link above.

Carbon Capture Breakthrough? Just might be!

Carbon Capture, more specifically CO2 capture, at coal fired power plants has the appeal of reducing CO2 emissions while still enabling us to use our most abundant fossil fuel resource, coal. However, capturing CO2 from current power plant flue gas is very costly because it is so diluted with nitrogen.

The potential CCS breakthrough involves oxidizing coal to release its stored energy using other sources of oxygen than air, so the dilution-with-nitrogen problem is eliminated. Other sources of oxygen can be iron oxide, or water.

Pulverized coal, mixed with iron oxide and heated to 1,650 deg F will react to form mostly CO2 and iron. The CO2 is very pure, approximately 99.5% after any water vapor has been condensed out, and thus the CO2 is ready for sequestration. The iron is then burned back to iron oxide using air as a source of oxygen, and it releases the energy originally from the coal to create steam and run a generator. The iron oxide thus formed is then recycled or "looped" back in the process.

Ohio State is the pioneer in this technology, known as Coal-Direct Chemical Looping (CDCL). The option using oxygen from water is known as Syngas Chemical Looping (SCL). Both are described in Midwest Energy News.

My view? I am optimistic! It is very revolutionary technology for power production, but it is very well known technology. The World's coal resources are vast, so where solar and wind generating potential are limited, it could become a valuable resource to help save our Earth, more or less as we know it, for future generations.

CCS - Carbon Capture and Sequestration

No, this is not about the current US Government spending sequestration program (which is explained HERE).

It is about capturing CO2 and storing it away somewhere, for a VERY long period of time. Coal fired power plants are the first obvious targets. Their flue gas is primarily nitrogen, water vapor, and large amounts of CO2. So the CO2 is far more concentrated than after the flue gas mixes with the atmosphere. Thermodynamics defines the energy required to "capture" CO2, either from flue gas or from the atmosphere. As you might expect, the theoretical energy (read cost) required is less for capturing CO2 from flue gas, where it is concentrated, compared to capturing it from the atmosphere, where it is very dilute.

Want to investigate further? Read Cory Simon's blog post on Scientific American. From that post we find that: "Capture technologies at present are estimated to cost 25-30% of a plant’s power output, driving up the price of electricity by around 80%........  the minimum theoretical energy.......  turns out to be ~5% of the output of the coal power plant, suggesting that there is room for improvement in current carbon capture technologies."

In Canada, how are things going to keep the politics of shale oil on a better environmental footing? Not so good relative to Canada's CCS plans, which have been very aggressive up to recently.

There are still many high level research programs going on, so maybe a breakthrough is possible to get us much nearer to the %5 of output theoretical limit. For instance, some novel organic-inorganic CO2 sponges.
 

Carbon Capture and Sequestration (CCS)

If all fits in our next Monday class schedule, we'll be wrapping up with this topic. So if you want to be prepared with some 2012 summary information, visit Ezra Klein's Wonkblog on the Washington Post.

Unfortunately, but not unexpectedly, CCS is going very slowly.