Friday, February 22, 2013

A Possibly Major Breakthrough: Coal Without CO2

Thanks to a reader.
As best as I can understand there are two separate topics in the news release, the oxidation and the CO2 capture.
After they have the carbon dioxide they have the problem all the scrubbers run into: What are you going to do with the stuff?
One route is to use the Solvay process to make sodium bicarbonate in which case a short of Arm & Hammer's owner CWD may be in order.

From THE Ohio State University:

New Coal Technology Harnesses Energy Without Burning, Nears Pilot-Scale Development  
COLUMBUS, Ohio—A new form of clean coal technology reached an important milestone recently, with the successful operation of a research-scale combustion system at Ohio State University. The technology is now ready for testing at a larger scale.

For 203 continuous hours, the Ohio State combustion unit produced heat from coal while capturing 99 percent of the carbon dioxide produced in the reaction.

L.S. Fan
Liang-Shih Fan
Liang-Shih Fan, professor of chemical and biomolecular engineering and director of Ohio State’s Clean Coal Research Laboratory, pioneered the technology called Coal-Direct Chemical Looping (CDCL), which chemically harnesses coal’s energy and efficiently contains the carbon dioxide produced before it can be released into the atmosphere.

“In the simplest sense, combustion is a chemical reaction that consumes oxygen and produces heat,” Fan said. “Unfortunately, it also produces carbon dioxide, which is difficult to capture and bad for the environment. So we found a way to release the heat without burning. We carefully control the chemical reaction so that the coal never burns—it is consumed chemically, and the carbon dioxide is entirely contained inside the reactor.”

Dawei Wang, a research associate and one of the group's team leaders, described the technology’s potential benefits. "The commercial-scale CDCL plant could really promote our energy independence. Not only can we use America's natural resources such as Ohio coal, but we can keep our air clean and spur the economy with jobs," he said.

Though other laboratories around the world are trying to develop similar technology to directly convert coal to electricity, Fan’s lab is unique in the way it processes fossil fuels. The Ohio State group typically studies coal in the two forms that are already commonly available to the power industry: crushed coal “feedstock,” and coal-derived syngas.

The latter fuel has been successfully studied in a second sub-pilot research-scale unit, through a similar process called Syngas Chemical Looping (SCL).  Both units are located in a building on Ohio State’s Columbus campus, and each is contained in a 25-foot-high insulated metal cylinder that resembles a very tall home water heater tank.

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....MORE
Here's an interview with Professor Fan at the Erie Digest.
And from MIT's Technology Review:

A Cleaner Way to Use Coal
A technology for generating electricity from coal without pollution achieves a milestone. 

Coal is abundant and cheap, but burning it is a dirty business. This week researchers at Ohio State University announced a milestone in the development of a far cleaner way to use the energy in coal—a process called chemical looping that has the potential to reduce or eliminate a wide range of pollutants, including carbon dioxide and smog-forming nitrogen oxides.

One version of the technology ran continuously for over a week in a 25-kilowatt test facility, the researchers reported, the longest any such process has run. The successful test clears the way to ramp up the technology in a one-megawatt demonstration plant that’s being planned in collaboration with the energy company Babcock and Wilcox.

In ordinary coal plants, coal is pulverized to make a fine powder and then burned in air to produce steam to drive turbines. This process makes very hot flames that can create the pollutant nitrogen oxide, and the carbon dioxide generated is difficult to isolate and capture because it makes up only a small fraction of the exhaust gases....MORE