Large-scale Atomic Vapor Laser Isotope Separation (AVLIS) operations began in 1986, the year after the DOE selected AVLIS as having the best potential to provide a low-cost, environmentally sound method to enrich uranium and replace, in an orderly way, the nation’s aging gaseous diffusion plants. Major technological improvements made in the 1990s brought uranium AVLIS—as well as AVLIS for plutonium—to the level of routine plant-scale operations.
An important milestone was reached in September 1991 when the Uranium Demonstration system at Livermore met all objectives in an integrated operational test of the lasers and beampath optics; the system for vaporizing molten uranium, separating isotopes, and collecting ions; and diagnostics and control systems. The copper-vapor lasers, in particular, generated more than 9,000 watts of power, and the dye lasers delivered greater than 85% of plant-scale required fluence to the separators. In July 1994, the United States Enrichment Corporation (USEC) gave the go-ahead for AVLIS advanced development. Created by the Energy Policy Act of 1992, USEC has responsibility for the nation’s uranium enrichment activities.
LLNL became site of the world’s first “laser-powered factory.” Completed in 1997, the pilot enrichment plant became the focal point for experts from Livermore, Bechtel National Inc., Duke Engineering, On-Site Engineering, Babcock and Wilcox, Lockheed Martin, AlliedSignal Corp., and USEC. The team tested commercial-scale equipment, making important improvements over time. Science and engineering innovations such as deformable optics for dye-laser beam uniformity, compact diode-pumped solid-state lasers to reduce costs, and use of line-replaceable units for operational sustainability would eventually benefit NIF and other projects at LLNL.
The pilot plant operated for more than one-and-a-half years. It processed several thousands of kilograms of uranium in test series aimed at verifying component performance, operational lifetime, and economics. By March 1999, the pilot demonstrations had verified projections that the technology could achieve enrichment at favorable costs, even without planned improvements. Tests of those improvements were interrupted by USEC’s decision in June 1999 to halt development of AVLIS technology due to changing market conditions and a combination of near-term factors that limited available funding.
