Seversk Technological Institute of National Research Nuclear University “MEPhI”

V. S. Аkishin, Scientific Consultant, ph. +7 (3823) 52-79-17
B. P. Belozerov, Professor
А. А. Gushchin, Scientific Consultant

Siberian Chemical Combine
V. M. Коrоtkevich, General Director

National Research Tomsk Polytechnic University
G. P. Khandorin, Professor, Department of Chemistry and Technology of Rare and Scattered Elements

In the given work the actuality and validity of making production for conversion of high-enriched weapon uranium into hexafluoride of energetic uranium meeting all sanitary requirements has been shown. Three-stage technological chain of producing the energetic uranium hexafluoride was described. The first stage included weapon uranium oxidation, dissolution of the obtained oxides in nitric acid with extraction refining of solutions, precipitation, drying and glowing. On the second stage producing the hexafluoride of enriched uranium was planned. The third stage consisted of mixing the enriched uranium hexafluoride with low-enriched one. Technological scheme of the installation and the basic equipment for producing the hexafluoride of enriched uranium were considered. The results of this project implementation were presented. We shortly described the device of auger fluoration reactor with air heatingand-cooling system. For the shaft seal of blade auger in the device we used the vacuum-tight hexafluoride seal which is industrially produced. For the gas filtering that comes out of reactor the filter with ceramic-metal multilayer filter patrons is applied. With the purpose of cleaning the patrons from depositions there was carried out their periodical impulse blowing out by means of compressed nyrtogen. For desublimation of enriched uranium hexafluoride two types of desublimators were developed and tested, one being three-dimensional and another with an outside “warm” (heated) wall. Eventually, it was determined that the desublimator with the outside “warm” wall has several advantages, such as the cavity fill, close to the projected value, and the uranium hexafluoride slippage of no more than 1–5 %. The described technical solutions provide safety of the given apparatus and maintenance of the installation and equipment (including vacuum density, corrosion stability, nuclear safe geometry, three-zone layout and remote control). The installation and equipment developed allowed producing energetic uranium hexafluoride which completely matches the requirements, and it was approved by the Russian government.

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