Navoi Mining and Metallurgical Combinat, Navoi, Uzbekistan:

I. A. Ivanova, Leading Production Engineer of the Uranium Geotechnology Facility of the Central Research Laboratory
O. P. Vasilenok, Head of the Central Research Laboratory, vasilyonok@ngmk.uz
B. T. Ruziev, Head of Uranium Geotechnology Facility of the Central Research Laboratory

The study is aimed at prevention of negative effect exerted by emulsion on uranium extraction. It is shown that considerable emulsification is caused in marketable solutions by the presence of polymeric species of silicic acid, first of all, and the objective is also set to select efficient agents to reduce the loss of valuable components and extractants. The authors analyze the causes and conditions of origination of stable emulsions in marketable solutions, and show that successful desiliconization is possible with flocculants, i.e. silicone compounds capable to infl uence ionic species of silicic acids toward polycondensation and sedimentation in acid solutions. The laboratory tests on selection of chemicals prove high efficiency of bentonite, magnesite and aluminium sulphate. For example, with the first of the listed agents, emulsification of solutions has decreased from 22 to 2%. The figures of the other two agents are similar. The pilot tests of bentonite confi rm the laboratory data: at bentonite consumption of 3.5 g/l, residual emulsification of solutions makes 2.5% as against the initial level of 36% (overall reduction by 93%). Alongside the listed agents, it is recommended to use gelatins to avoid stable emulsification during liquid extraction of uranium.

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