“While some day we may be able to produce hydrogen by breaking up water molecules in association with the high-temperature heat from nuclear power reactors, or through renewable energy technologies, right now the most cost-effective way to produce hydrogen is with coal,” says Chris Shaddix, principal investigator for clean coal combustion at Sandia’s Combustion Research Facility.

Two different approaches to burning coal are now under study:

* The first, called oxy-combustion, combines coal with pure oxygen.
* The second, called gasification, burns coal only partially to create a fuel-gas.

The first approach is driven by concern over emissions of CO2 and other pollutants. The burning of coal in oxygen is a near-term solution that with current knowledge can produce exhaust streams that are close to pure CO2, says Shaddix. Harmful pollutants like nitrogen oxides, sulfur compounds, and mercury are virtually eliminated.

The oxy-combustion approach is favored by companies in Japan, Canada, Germany, and elsewhere, where pilot plants are under construction.

U.S. companies tend to favor gasification technologies, which offer higher efficiency and low pollution formation. One of these technologies, called steam reformation, combines the coal with steam in a hot environment to produce a “syngas,” composed mostly of carbon monoxide (CO) and hydrogen.

Once the syngas is produced it can be burned directly in a turbine to produce power. Or the syngas can be further reacted with more steam to shift the remaining CO to CO2 and produce more hydrogen.

The competition between Sandia and Los Alamos is a spectator sport here in New Mexico. At least when they take the time to work at civilian rather than military tasks.



  1. Steven Tate says:

    So why has no one started cracking coal to get more standard I.C.E. fuel out of it? Its been done, more than 10 years ago it was deemed too expensive as the process would not be economically feesible unless gas prices were at $2 per gallon. So now, gas prices are above that, why haven’t we seen the use of Coal Cracking or Oil Shale on a large scale yet? In theory, if we started using these other resources to produce “gasoline” with we could have prices at just over 2$ per gallon for the next hundred+ years.

    As a side note, fuel cell research going on at Battelle (Pacific Northwest National Labs) seems to suggest that we shouldn’t count on hydrogen powered cars for another 15 years.

  2. Mr. Fusion says:

    Steven

    I suggest there isn’t any large scale plants running is because there just aren’t any plants. No one wanted to invest in the plants when petroleum prices were below $30 barrel. Now that the price looks to be above $60 for some time, maybe some more projects will get started.

    The same thing happened with the oil sands in Alberta. When oil was below $10 a barrel (or so) it wasn’t economical to process the oil. It is not only profitable now, but the plants there are going all out on this.

    The part that got my attention is that the pollutants, such as nitrogen, sulfur, and mercury will not be expelled into the atmosphere. What will they do with the excess CO2?

  3. Chase says:

    Pardon me if I’m wrong here, but doesn’t it defeat the purpose of switching to hydrogen by using a process that makes greenhouse gases? Simple electrolysis of water seems smarter, gven that the byproduct would be oxygen, rather than carbon dioxide.

  4. Jetfire says:

    Chase you need something to make the Energy for the Electrolysis. The thing their looking at what is the most effecient way. They saying while they’re burn coal in a clean way the can get Hydrogen from the burning prosses and no need to waste the energy on Electrolysys.

    Mr. Fusion the CO2 is not released in the atmosphere. “Add in the possible benefits of separating and storing carbon dioxide (CO2) emissions from the power plant stacks”. They capture it.

  5. Mr. Fusion says:

    Jetfire

    Capturing CO2 is great. But then what? Is there some way to store it in a solid form or will always be stored under pressure? I know that CO2 is often used to pressurize oil wells to gain more oil recovery, but I’m sure the amount of CO2 outstrips even this use. I’m just asking.


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