ALUMINUM ALUMINUM ALUMINUM ALUMINUM ALUMINUM 
Project Fact Sheet 
WETTABLE CERAMIC-BASED DRAINED CATHODE 
BENEFITS 
APPLICATION 
TECHNOLOGY FOR ALUMINUM ELECTROLYSIS CELLS 
ü Potential total energy savings of 
1,500 megawatts (MWe) per year 
(when applied to the current U.S. 
annual production of aluminum) 
ü Potential to increase cell efficiency by 
13 to 20 percent 
Through successful development, the 
Wettable Ceramic-Based Drained 
Cathode Technology for Aluminum 
Electrolysis Cells project promises to 
provide stable ceramic cathode lining 
materials for reduced energy consumption 
during aluminum production. 
NEW TECHNOLOGY WILL REDUCE ENERGY DURING 
Anode Stem 
Carbon Anode 
1.5 to 1.75 Inches Anode-to-Cathode Distance 
Metal Pad 
Cathode Block 
Cathode Collector Bar 
Ram Carbon 
Anode Stem 
Carbon Anode 
1 Inch Anode-to-Cathode Distance 
Ceramic-Based Material 
Cathode Collector Bar 
Ram Carbon 
ALUMINUM PRODUCTION 
Reynolds Metals Company, Kaiser Aluminum & Chemical Corporation, and 
Advanced Refractory Technologies (ART) will collaborate to develop and evaluate 
ceramic-based materials and the necessary engineering packages to retrofit 
existing reduction cells as a means to improve the performance of the Hall- 
Héroult cell. ART will produce ceramic-based tiles or coatings that will be used 
as the “drained” lining in two 70 kiloampere (kA) prebake cells. The durability of 
the candidate materials and the performance of the drained cathode design will 
be evaluated during a one-month test using 12 kA pilot reduction cells. 
CATHODE CELLS 
CONVENTIONAL CELL 
DRAINED CATHODE CELL 
Conceptual schematic drawing of a conventional cathode cell versus a drained cathode cell. 
OFFICE OF INDUSTRIAL TECHNOLOGIES 
ENERGY EFFICIENCY AND RENEWABLE ENERGY ü U.S. DEPARTMENT OF ENERGY
Project Description 
Goal: Develop ceramic-based materials and necessary engineering packages to retrofit 
existing reduction cells in order to reduce the energy consumption required for making 
primary aluminum. 
The ceramic materials will be used in a drained cathode configuration which will provide a 
stable, molten aluminum wetted cathode surface. By eliminating the wavy, irregular 
molten aluminum pool as the cathode and replacing it with a stable ceramic surface, the 
anode-to-cathode distance can be reduced, thereby reducing the electrical resistance. 
Stable operation of the new cathode technology will require the development of new 
process control algorithms for the management of alumina feeding, anode bridge movements, 
and increased sensitivity to cell instability. 
This project includes the following activities: 
1. Development and evaluation of candidate ceramic-based materials (tiles or coatings); 
2. Development of the drained cathode cell design; 
3. Evaluation of candidate materials and drained cathode cell design in 12 kA pilot cell 
tests; and, 
4. Evaluation of candidate materials and drained cathode design in retrofitted 70 kA 
prebake cell tests. 
Progress and Milestones 
ü Develop Cathode Materials and Manufacturing Techniques (Spring 1999) 
ü Design, Operate and Evaluate Two Pilot Cell Tests (Spring 2000) 
ü Design, Operate and Evaluate Two Industrial Cell Tests (Summer 2002) 
Commercialization Plan 
Long-term (three-to-four years) confirmation of the durability of the ceramic-based 
materials and cell operational practices at the Kaiser Aluminum Mead Works Plant with 
eventual expanded use of the wettable ceramic-based cathode technology throughout 
the entire aluminum reduction plant. 
PROJECT PARTNERS 
Advanced Refractory Technologies 
Buffalo, NY 
Kaiser Aluminum & Chemical 
Corporation 
Kaiser Aluminum Mead Works Plant 
Mead, WA 
Reynolds Metals Company 
Muscle Shoals, AL 
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/IOF/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