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NRC approves TerraPower construction permit
Today, the Nuclear Regulatory Commission announced that it has approved TerraPower’s construction permit application for Kemmerer Unit 1, the company’s first deployment of Natrium, its flagship sodium fast reactor.
This approval is a significant milestone on three fronts. For TerraPower, it represents another step forward in demonstrating its technology. For the Department of Energy, it reflects progress (despite delays) for the Advanced Reactor Demonstration Program (ARDP). For the NRC, it is the first approval granted to a commercial reactor in nearly a decade—and the first approval of a commercial non–light water reactor in more than 40 years.
Mark F. Sulcoski, Kenneth W. Tobin, Jack S. Brenizer, Jr.
Nuclear Technology | Volume 82 | Number 3 | September 1988 | Pages 355-362
Technical Paper | Analyse | doi.org/10.13182/NT88-A34136
Articles are hosted by Taylor and Francis Online.
The University of Virginia’s real-time neutron radiography facility was characterized by measurement of the total neutron flux, gold/cadmium ratio, neutron/ gamma ratio, and the effective collimator length-to-aperture diameter (L/D) ratio. The real-time neutron imaging system and collimator were further characterized by measuring the modulation transfer function (MTF) of the system. The collimator effectiveness was measured by using the MTF to determine the “unparallelism” of the neutron beam. The MTF was also used to determine the effects of any reactor or beamport changes and to examine the effect of various system components on image quality. The computer-based image processing system allowed rapid calculation of the MTF and the collimator effectiveness. The results of these measurements, using no collimator and a simple tube collimator, demonstrated the method’s ability to determine the effective L/D ratio. The MTF measurement scheme provided a fast, reliable, and reproducible means of monitoring any changes in the real-time system, including both the neutron beam and the electronic components. The MTFs for various system components were measured using a separation technique. A parameter fN was used to give a quantitative measure of an individual system component’s performance.