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New Process Takes Energy From Coal Without Burning It
rtoz writes "Ohio State students have come up with a scaled-down version of a power plant combustion system with a unique experimental design--one that chemically converts coal to heat while capturing 99 percent of the carbon dioxide produced in the reaction. Typical coal-fired power plants burn coal to heat water to make steam, which turns the turbines that produce electricity. In chemical looping, the coal isn't burned with fire, but instead chemically combusted in a sealed chamber so that it doesn't pollute the air. This new technology, called coal-direct chemical looping, was pioneered by Liang-Shih Fan, professor of chemical and biomolecular engineering and director of Ohio State's Clean Coal Research Laboratory."
How does the lack of pollution from the process compare against that generated from the acquisition of the coal?
Is it possible/practical to convert an existing coal power plant?
Is there an appreciable energy/pollution cost to produce the fine powder coal used in the process?
How much energy is consumed or how much pollution is produced in transporting the coal to the reactor?
Is the process itself efficient in regards to the energy output when compared against the total energy costs?
I'm sure there's a lot of other things that don't spring to mind instantly, but I'm certainly not an expert on any of this. Doubts notwithstanding, this is pretty cool.
just build it bigger!
Or if that can't be done economically, just build millions of little ones!
Oh that's not economically feasible either because each one requires a lot of labor to build? Hmm.... *thinks*
Ok let's just forget about the whole thing and go nuclear.
The part that worried me was more the fact that CO2 was still produced, it was just contained within the chamber (the benefit of their technique seemed to just be less/no air space required in the chamber).
Sequestering CO2 is not simple, and is currently done mostly by pumping it into used oil fields. It's not certain whether these costs were factored in.
Coal is 84% carbon, 10% oxygen, 4% hydrogen, and 2% nitrogen (or so). Short of nuclear fission or fusion, you're going to get carbon and oxygen out of it no matter what you do.
The question is how much energy you get out. If this process were twice as efficient (in terms of CO2 per MW) then it would still be a worthwhile improvement wouldn't it?
Comment forecast: Bits of genius surrounded by a sea of mediocrity.
Sequestering CO2 is not simple, and is currently done mostly by pumping it into used oil fields. It's not certain whether these costs were factored in.
Sequestering it is a lot simpler if you can simply draw if off the top of the CLOSED chamber rather than trying to scrub it out of the stack.
You've got half the battle won already.
What to do with it long term is another problem. But its a problem you would have anyway, so having the CO2 handed to you all
contained is better than where we are today.
Besides coal ash, it appears CO2 is the only by-produce that is not recycled back into the feed-stock.
But, hey, Clean Coal stories have to be knocked down immediately. We can't have it prove even partially successful under any /rollseyes.
circumstance.
Sig Battery depleted. Reverting to safe mode.
This is the kind of science that will save us from Global warming. I know how grand Solar and wind seem grand, but they aren't powering shit yet.
Wind is powering all sorts of "shit" in Europe. Denmark is pushing about 28% penetration of wind into their power market and many of the surrounding countries have penetrations of 10-20%. And they are building a hell of a lot of offshore wind farms.
Just because the U.S. is slow to get off its ass doesn't mean the rest of the world is.
Left MS Windows for Linux Mint and never looked back!
Vote for Bernie in 2016!
Last I checked, burning is combustion.
Nor do I understand what the hell is advantageous about it. They admit to oxidiation of the hydrocarbons (ie, burning), heating it to high temperature, and the release of CO2 gas. So exactly what is so great about it?
From TFA:
No other lab has continuously operated a coal-direct chemical looping unit as long as the Ohio State lab did last September. But as doctoral student Elena Chung explained, the experiment could have continued.
“We voluntarily chose to stop the unit. We actually could have run longer, but honestly, it was a mutual decision by Dr. Fan and the students. It was a long and tiring week where we all shared shifts,” she said.
Fan agreed that the nine-day experiment was a success. “In the two years we’ve been running the sub-pilot plants, our CDCL and SCL units have achieved a combined 830 operating hours, which clearly demonstrates the reliability and operability of our design,” he said.
His entire staff of grad students manned the thing and kept feeding it coal for a week and it ran nonstop the whole time, and could have kept going. So this appears to be a solved problem.
Weaselmancer
rediculous.
For a fuel that requires little or no processing it's extremely energy dense. Ultimately the problem wouldn't be with the process but the budget minded power companies. There's a reason "clean coal" is like bigfoot, largely a myth. Clean coal would cost more money reducing profits. It's the reason the industry doesn't remove mercury and coal dust from the exhaust, reduced profits. They even had a government mandate and the still waited until the deadline and are now saying it's too hard. The process can trap 99% of the CO2, the trick is keeping the power companies from not releasing it into the atmosphere to save money. White Diesel is a great source of fuel and second only to natural gas for being a clean fossil fuel but it involves stripping of the CO2 and you are faced with the same problem. Sequestration isn't as simple as it sounds. Compressing huge amounts of CO2 gas takes energy and the underground storage areas don't tend to be near power plants. When you start burning more coal just to store the CO2 from the last batch the efficiency goes way down. If the existing plants had been positioned and built with all this in mind we wouldn't have all these problems. Now there are no cheap and easy solutions. Personally I prefer using algae or greenhouses to store the CO2. Try this approach, pump the CO2 into large cheap greenhouses that grow Kenaf, it's related to hemp but totally legal and interchangeable with industrial hemp. Use as much as industry needs for fiber and seed oil then turn the rest into biochar, a good one to read up on if you aren't familiar. The char can be mixed with farmland improving the soil and it'll absorb the excess fertilizer reducing run off and reducing the amount needed to grow food. The carbon is stored for thousands of years, if not millions. The power companies get to make extra money off the Kenaf and they greatly reduce the CO2 and mercury released. The Mercury will get trapped in the char and the CO2 will be stored as solid carbon. These days they try to solve everything with technology when mother nature has been doing it for billions of years.
I've always been confused by "Carbon Neutral" propaganda. For example, we have always had the same amount of carbon in the environment. Just over the years it's been sequestered into oil/coal/etc. However, now if it's been out of commission for thousands of years and it's somehow out of the equation. So burning oil/coal/etc is just normalizing the balance.
No, no, no! You missed the biggest sink for carbon. The one that is orders of magnitude greater than all the others put together: limestone (60 million gigatons vs the 720 gigatons in the atmosphere and the 38,000 gigatons in the oceans). If you think that normalizing the balance with all of the carbon that has been taken out of the environment is a good thing, then you must be from Venus.
Just like the way it subsidizes solar and wind installations, and sends billions to failing solar technology companies.
Gamingmuseum.com: Give your 3D accelerator a rest.
They just burn it with pure oxygen instead of with air. The innovation, and it is an innovation IMHO, is that they used iron to capture and transfer the oxygen. This prevents the forming of NOx, which is a good thing. ...
This means they can burn the coal hotter without emitting dangerous amounts of NOx.
1. They let iron pellets rust. Or they buy rust in the first place.
2. They put the rust pellets into the chamber with coal dust.
3. They ignite the mixture (this requires a bit more heat than usual burning. At least 1566 ÂC or 2850.8 F)
4. The coal dust pulls the oxygen out of the rust and binds it with the carbon into quite pure CO2.
5. Heat (a lot of it)
6. Use the heat in a default thermoelectric power plant.
7. The pellets can rust again, to capture oxygen.
8.
9. Profit.
If they would combine it with an iron smelting plant then the energy required in step 4 to pull the oxygen out of the rust would not be wasted. Then the iron pellets are one of the end results. Of course, then you'd have to emit step 7.
To me this seems familiar. If I am correct this is the way Thermite works, just with aluminium powder instead of coal dust.
Well, I might have a way, but it only works on a semi spherical planet in a vacuum.