Prague, Czech Republic:

M. A. Meretukov, Independent Expert, Professor, Doctor of Technical Sciences, e-mail: mamer@inbox.ru

UGC The Gold Mining Company, Plast, Russia:

K. I. Strukov, Company President, Doctor of Technical Sciences, e-mail: ugold@ugold.ru

When relying on CIP and RIP processes for recovering heavy non-ferrous, rare, noble and radioactive metals, the key factor responsible for acceptable economic performance includes adsorbent wear, which occurs due to abrasion and osmotic shock. Nowadays, more than 50% of gold in the world gets recovered with the help of CIP process. A survey of foreign mining and metallurgical companies helped establish that every plant that relies on the CIP process loses around 2th t/y of activated carbon containing Au 0.11–0.14 kg/t. To recover gold from dumped carbon, the author proposes to use the methods of heat treatment, electrochemistry and flotation. The continuous process of ion-exchange sorption of uranium from slurries (after separation of sand), which is based on the use of Pachuca tanks with in-built screens, is used in many countries, including South Africa, USA, Australia, Russia and Uzbekistan. Gelular resins have lower resistance to osmotic effects, whereas macroporous resins have higher resistance to chemical treatment. At the same time, high porosity makes them less resistant to physical abrasion. Today, the biggest resin suppliers (such as Purolite, Rohm and Haas, Dow and Lewatit) have enhanced the quality of their RIP resins designed for hydrometallurgical extraction of uranium. The yearly wear rate of these resins normally does not exceed 5%. It is proposed to use froth flotation for extracting fine particles of chelating resin, and supercritical fluid – for regeneration of gold contained in the resin.

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