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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.
Makoto Ueda, Shigeto Kikuchi, Hironori Kumanomido, Takeshi Seino
Nuclear Technology | Volume 97 | Number 1 | January 1992 | Pages 131-141
Technical Paper | Nuclear Criticality Safety | doi.org/10.13182/NT92-A34631
Articles are hosted by Taylor and Francis Online.
An active neutron multiplication method is studied in laboratory experiments aiming at establishing and improving nondestructive measurement methods for a spent light water reactor fuel bundle in water. The fuel rods used in the experiments consist of 1.0-cm-diam UO2 pellets enriched to 1 to 3 wt% 235U, clad in 1.18-cm-o.d. aluminum tubes. The rods are arranged in square arrays spaced to form a 1.52-cm lattice. The analysis is carried out by two- or threedimensional, three-energy-group diffusion calculations. A simple empirical expression for the correlation between the neutron flux and the effective neutron multiplication factor keff is proposed in which a constant term is added to the well-known formula for one-point subcritical flux. The new expression has been found to be applicable to high-precision measurements. Through an experimental study of the correlation between the neutron flux profile and the neutron source response to a detector and studies of the new correlation expression, an improved measurement system is presented that is suitable for more precise measurements of keff.
