ALUMINUM ALUMINUM ALUMINUM ALUMINUM ALUMINUM 
Project Fact Sheet 
ADVANCED ANODES AND CATHODES UTILIZED IN 
BENEFITS 
APPLICATIONS 
ENERGY-EFFICIENT ALUMINUM PRODUCTION CELLS 

 Possible energy savings of six trillion 
Btu annually in the U.S. by 2010 
because of the improved performance 
of the Hall-Héroult cell 

 Elimination of carbon and fluorocarbon 
emissions 

 Reduction of cyanide formation and 
dust emissions 

 Potential energy costs saving of $90 
million annually in the U.S. by 2010 

 Potential non-energy savings of $20 
million annually in the U.S. by 2010 
This improved primary aluminum 
smelting technology has application for 
new and retrofitted traditional Hall- 
Héroult production cells. 
NEW ALUMINUM PRODUCTION CELLS WILL REDUCE ENERGY 
Emissions 
Anode 
3.8 Volts 
NiO-NiFe2O4-Cu 
1 Inch 
2 TiB -Al2O3 
Nickel Compound 
(Non-Hazardous) 
REQUIRED FOR SMELTING 
For over 110 years, the aluminum industry has relied on the traditional (and 
energy intensive) Hall-Héroult process for aluminum smelting. With the recently 
developed advanced materials used for anodes and cathodes, it may be possible 
to significantly reduce the anode-cathode distance and, thus, reduce the energy 
required for aluminum smelting. Annually, over four million tons of aluminum are 
produced by smelting by the U.S. aluminum industry. More than 63,000 British 
thermal units (Btu) per pound are consumed in the process. Using the improved, 
more energy efficient process, smelting plants may be able to cut their energy 
use by 25 to 30 percent or more. These savings would contribute significantly to 
improving the economic competitiveness of the U.S. aluminum industry. 
The Alcoa Technical Center will demonstrate the commercial viability of the 
design of an energy efficient/high productivity aluminum smelting cell that uses an 
oxygen producing anode and a cathode material that is wetted by aluminum. The 
combination of these two technologies provides a dimensionally stable interelectrode 
distance, which can be used to greatly improve both the energy and 
productivity efficiencies of the Hall-Héroult cell. This project addresses advanced 
development of primary aluminum production defined in the Aluminum Industry 
Technology Roadmap. 
ALUMINUM PRODUCTION CELLS 
Emissions 
4.96 Volts 
Cyanide 
Formation 
Aluminum production cells: traditional design versus improved design -- resulting in the 
reduction of dust, fluorides, effluents, cyanide and sludge formation, sodium and bath penetration, 
spent potlining, SO, NOX, and in the elimination of CO, CO2, and CF4. 
TRADITIONAL IMPROVED 
Carbon Anode 
1.75 Inches 
Molten Aluminum 
Cathode 
Carbon-Lined 
OFFICE OF INDUSTRIAL TECHNOLOGIES 
ENERGY EFFICIENCY AND RENEWABLE ENERGY 
 U.S. DEPARTMENT OF ENERGY 
Cathode
Project Description 
Goals: Demonstrate advanced materials for inert anodes and wetted cathodes and an 
optimum design and process for smelting aluminum by designing, constructing, and 
operating advanced bench scale and pilot-scale aluminum production cells. 
The objective is to assess the long-term chemical stability of oxygen-producing ceramic 
metallic anodes and stable aluminum wetted cathodes for energy efficient electrolytic 
production of aluminum. The project will also describe how the anode and cathode 
materials are produced cost effectively, and will define the optimum operating parameters 
for the production cell. 
Progress and Milestones 

 Design commercial production cell considering advanced concepts. 

 Develop improved anodes and enhanced anode connections. 

 Scale-up improved cathodes and improve vertical cathode connections. 

 Improve sidewall barrier and lid of the production cell. 

 Model the cell itself, cell current efficiency, and anode wear. 

 Design, build and bench test the new production cell. 

 Design, build and bench test pilot-scale production cell. 

 Optimize design of the commercial production cell. 
Commercialization Plan 
The drastically reduced energy costs are expected to drive the rapid commercialization 
of this technology once the benefits are proven. After this project is complete, Alcoa 
plans to construct, operate, and autopsy two commercial scale tests. If the outcome of 
this project and the commercial scale tests are successful, the technology is expected to 
be commercialized in early 2005. 
PROJECT PARTNERS 
Alcoa Incorporated 
Alcoa Technical Center 
Alcoa Center, PA 
EltronResearch,Inc. 
Boulder,CO 
FOR ADDITIONAL INFORMATION, 
PLEASE CONTACT: 
Sara Dillich 
Office of Industrial Technologies 
Phone: (202) 586-7925 
Fax: (202) 586-1658 
sara.dillich@ee.doe.gov 
http://www.oit.doe.gov/aluminum 
Please send any comments, 
questions, or suggestions to 
webmaster.oit@ee.doe.gov. 
Visit our home page at 
www.oit.doe.gov 
Office of Industrial Technologies 
Energy Efficiency 
and Renewable Energy 
U.S. Department of Energy 
Washington, D.C. 20585 
January 1999