I missed this article until I saw the comments today. I concluded a while back that once emissions get to the CO2 stage, we are pretty much sunk. CO2 is a very stable compound. It takes a lot of energy to convert it to anything else, like methanol or gasoline.
I concluded that the place to intervene is at the CO -- carbon monoxide -- stage. Carbon monoxide is much less stable than CO2 and takes much less energy to convert it to something else. It may be physically possible and economically viable to do something with carbon monoxide. Your article hints at this.
An integrated gasification combined cycle power plant initially produces syngas consisting of carbon monoxide and hydrogen. It is possible to separate the carbon monoxide from the syngas. Here is an opportunity to do something with the carbon monoxide. The power plant would then be fueled exclusively with the hydrogen part of the syngas.
A few months ago, I published an article on this in Energy Pulse. Your article talked about converting the CO2 or CO to liquid transportation fuels. My plan was to convert carbon monoxide back to carbon and oxygen and then re-use the carbon. I got crucified even worse than you did by the readers for violating the laws of thermodynamics. (In my reader comment at the end, I tried to clarify that I was not violating the laws of thermodynamics. I had not included the reaction that produced the vast majority of the energy that drives the process. I am not reversing that reaction. I am suggesting reversing the reaction that provides only a little of the total energy and takes only a little energy to reverse.)
Some parts of your article sound like using a gasifier to turn coal into CO-rich syngas and then turn that into liquid fuel, which is just traditional Fischer-Tropsch gasification. The Germans did this in WWII and Sasol did it in South Africa. The problem is that CO2 emissions are still given off when the fuel is burned.
This is, by the way, how I figured out that IGCC plants are fueled by water (when sequestration is employed). Consider if it was possible to pull the carbon monoxide or carbon dioxide out and convert it into a solid. What would you do with this solid -- there would be a lot of it. The answer is really simple -- put it back in the coal cars, haul it back to the mine, and put it back in the ground. Basically, an IGCC plant with (solid) sequestration would dig coal out of the ground, put it in a coal train and send it to the IGCC plant, use the carbon in the coal to extract hydrogen from water and make it into syngas, separate the CO and hydrogen in the syngas, make the CO into a solid and send the hydrogen from the syngas to power plant, put the solidified CO/CO2 back in the coal train and send it back to the mine. Note that the CO/CO2 never enters the power plant (in this case and also in the case of geologic sequestration of CO2). With sequestration, CO or CO2 are separated out before it enters the power plant -- it does not produce power. It goes from the coal mine to sequestration without being physically used for generation. Its purpose is only to extract hydrogen from water. My thought was why not re-use the carbon to extract hydrogen from water rather than bringing in more new carbon in the form of coal.
Chris Neil
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