All-Russian Research Institute of Chemical Technology, Moscow, Russia:
V. A. Tolkachev, Leading Researcher
N. P. Paskhin, Senior Researcher
D. V. Maynikov, Senior Researcher, e-mail: didima06@mail.ru

Ulba Metallurgical Plant applies the labor-intensive beryllium concentrate processing. In order to exclude this process from the production, we offer the concentrate opening in autoclave using sodium alkali in beryllium production technology. However, the pulps, formed after the alkali leaching, are hardly separated without flocculant additives and have low filtering rates. This is explained by a high degree of crushing of initial solid material and high alkali concentration used during leaching. Research results offered the methods of increasing the efficiency of pulp filtering and washing the sediments, obtained after alkaline opening of ore material. Production capacity of pulp filtering was considerably increased by CaO addition on the leaching stage. The pulp separation was significantly increased with simultaneous using CaO on the leaching stage and usage of flocculating agents for pulp thickening. Thickened flocculated pulps were filtered and washed under pressure with average production capacity of 30 kg/(m²·cycle). Having rather small consumption of rinsing water, the washing efficiency in all experiments was 99.9%. The filter-press with squeezed membranes is recommended for pulp filtering and sediments washing in industry. The obtained data may be used with further investigation of beryllium obtaining technology.
This work was carried out within the Federal Target Program of the Ministry of Education and Science of the Russian Federation “Investigations and developments by the priority ways of development of the scientific and technological complex of Russia for 2014–2020”. Subsidiary agreement No. 14.582.21.0008, unique identifier of the agreement RFMEFI58215X0008.

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