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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.
Tsuguyuki Kobayashi
Nuclear Technology | Volume 177 | Number 2 | February 2012 | Pages 231-244
Technical Paper | Reprocessing | doi.org/10.13182/NT12-A13368
Articles are hosted by Taylor and Francis Online.
A simple procedure to simulate the important kinetic features of counter-current processes in pulsed columns has been developed. The overall mass transfer coefficient was simplified to be constant along the column, and the stripping of Pu4+ by hydroxylamine is assumed to be instantaneous to avoid complex reaction rate calculations. The number of calculation cells can be determined by making calculations with an increasing number of cells until its influence becomes small enough. The validity of these simplifications was confirmed by comparing the calculation results with a wide range of measured data from extraction and stripping as well as Pu partition tests with laboratory, engineering, and pilot scale columns. This procedure is intended for use in a conceptual design study of a future fast breeder reactor (FBR) reprocessing plant. An example of its application in a flow sheet calculation was demonstrated, where a coextraction process of U and Pu was simulated to find the conditions to obtain a solution with Pu/(U + Pu) ratio being 30% from a typical feed of FBR spent fuel solution.