EXPERIENCE IN LEACHING, SEPARATION AND PURIFICATION OF URANIUM FROM ROMANIAN URANIFEROUS MINERAL ORES

摘要

Nuclear fuel technology is determined by the type of nuclear reactor to be used and by the chemico-mineralogical characteristics of the raw material, the production units in Romania manufacturing nuclear fuel under the form of sinterable UO_2 for a nuclear reactor, PHWR - Candu type, which operates with natural uranium and heavy water moderator. The raw material from which uranium is extracted at industrial level is an ore with silica gangue and a content of over 10% alkaline carbonates. The paper presents the way of development and application of the nuclear fuel technology which is based on carbonate leaching of the uranium ore, technical concentrate purification by TBP - extraction, calcination of ADU to U_3O_8, reduction to UO_2 and nitrogen inert treatment of the pure nuclear dioxide. The original contribution of the Romanian specialists in the research, design and industrial processing fields for the developed technology has a significant importance in this paper. The flowsheets for the extraction, purification and pure nuclear UO_2 production are also presented.