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Zero Emission Coal (Los Alamos)

(One of a series of UFTO Notes based on the recent visit to Los Alamos National Laboratory)

Zero Emission Coal

Los Alamos is working to eliminate the environmental concerns associated with the use of fossil fuel, which will continue to be an important energy source well into this century. One technology the Laboratory is developing to achieve this goal is a zero emission process for converting coal and water into hydrogen, which is then converted into electricity, with virtually no emissions of pollutants. Thirteen entities with interests in coal production and energy generation have teamed up to form the Zero Emission Coal Alliance (ZECA) which plans to commercialize this process within five years.

The Technology In the context of DOE’s “Vision 21” goal to eliminate environmental concerns from the use of coal. Los Alamos is developing technology to achieve a zero emission process for converting a coal and water slurry into hydrogen, which is in turn converted to electricity via a high-temperature solid-oxide fuel cell.

The new process builds on CONSOL’s CO2 Acceptor Process, which was piloted in the 1970’s. While still relying on cycling of calcium oxide (CaO) to drive the production of hydrogen, enhancements produce separate streams of hydrogen and CO2. The hydrogen is used to generate emission-free electricity and the CO2 is reacted with abundant magnesium silicates to be permanently sequestered as a solid, inert and stable mineral carbonate.

Hydrogen gas is produced from water and coal using a calcium oxide (CaO) to calcium carbonate (CaCO3) intermediary reaction. Through a subsequent reaction, the calcium carbonate generated by hydrogen production is converted back into calcium oxide and a pressurized stream of pure CO2. The calcium oxide is recycled to drive further hydrogen production, and the CO2 stream is ready for easy disposal.

The hydrogen is fed to solid-oxide fuel cells to generate electric power, and the ~50% of waste heat produced by the fuel cells is not truly wasted because it is reinjected into the process to drive the calcination reaction.

The already pressurized CO2 stream is reacted with magnesium or calcium silicate mineral deposits to form geologically stable mineral carbonates. (The reaction is part of the natural geological carbon cycle; therefore, all mineral end products are naturally occurring and completely benign.) The mineral sequestration process is economically viable because the CO2 stream is non-mechanically pressurized in the hydrogen production process and the carbonation reaction is exothermic (i.e., it creates energy instead of consuming it).

In addition, the types of mineral deposits needed to carry out the reaction are abundant enough to handle all the carbon associated with the world’s coal reserves. Magnesium-rich ultramafic rocks, primarily peridotites and serpentinites, are the main candidates for mineral carbonation. Deposits distributed throughout the world, though in specific concentrated areas on each continent.
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The Alliance
Thirteen entities from the United States and Canada with interests in coal production and the use of coal for electrical generation have agreed to contribute $50,000 each to form ZECA.

Phase I: ZECA is currently structured with an executive team headed by Jim Berson, Director of Planning and Business Development from Kennecott Energy/Rio Tinto, a technology team headed by Dr. Hans Ziock, senior scientist at Los Alamos National Laboratory, and a business team headed by Alan Johnson, President of The Coal Association of Canada. The goal of Phase I is to develop a business plan and a technical plan leading to the completion of a pilot plant in a five year time frame.

ZECA has begun to proceed with Phase I. The alliance however still welcomes the participation of additional members to ensure a broad spectrum of industry participation and expertise. As alliance members, participants in Phase I have the opportunity to help guide the work conducted under the supervision of the technical and business committees, as well as the opportunity to serve or participate on those committees at their discretion.

Additional information is available online:
http://www.lanl.gov/energy/est/zec/zec.html

for technical information:
Klaus Lackner, 505-667-5694, ksl@lanl.gov
Hans Ziock, 505-667-7265, ziock@lanl.gov

for business information:
Jim Berson, 307-687-6049, bersonj@kenergy.com
Alan Johnson, 403-262-1544, johnson@coal.ca

(I have several technical papers from Los Alamos, which I can send on request.)