Factors affecting bioleaching in the processing of non-metallics

Biotechnological treatment of non-metallics is based on bacterial leaching of raw material and dissolution of Fe. Bacterial iron dissolution ability is dependent on various physicochemical factors as temperature, acidity of solutions, redox potential, rapidity of water circulation and presence of organic sources. The Fe content in the quartz sands and feldspar samples by the biological leaching decreased as much as 60% and by subsequent using of electromagnetic separation of feldspars, the decrease of Fe content in 74% was achieved. However, the application of magnetic separation of quartz sands after bioleaching resulted in total iron removal of 93% and in such combined way prepared product contained 0.024 % of Fe2O3. Achieved results on iron removal point to the fact that combination of leaching and magnetic separation enables to obtain product usable in glass and ceramic industry.

Scientific search under the pressure of high responsibility: development of the technology of electromagnetic isotope separation in the framework of the USSR Atomic project

One of the ways to obtain nuclear explosives for the manufacture of the first atomic bombs was the separation of uranium isotopes by electromagnetic (mass spectrographic) method. The theoretical justification and experimental separation of uranium isotopes by this method was carried out by L. A. Artsimovich in the Laboratory No. 2 of the USSR Academy of Sciences. By the middle of 1945, L. A. Artsimovich had obtained results at the experimental facility indicating the possibility of stable enrichment of uranium with the U-235 isotope using this method. Having the results of the experiments, the Design Bureau at the “Electrosila” plant (D. V. Efremov), with the participation of the Research Vacuum Institute (S. A. Vekshinsky) and the “A” Institute (M. Ardenne), developed a project of an industrial multi-chamber installation for electromagnetic separation of uranium isotopes SU-20. Such an installation was manufactured and put into operation at the newly created plant in the Urals, which allowed in 1951 to obtain the necessary amount of uranium-235 for the RDS-3 atomic bomb. After 1952, the technology of electromagnetic separation was no more used for the separation of uranium isotopes due to the improvement of more productive equipment for gas-diffusion separation of isotopes. The equipment of the electromagnetic isotope separation plant built in the Urals was used to produce lithium-6, needed to equip the first thermonuclear charge, which was successfully tested in 1953. In the next years, the electromagnetic isotope separation plant was involved in the manufacture of isotope products for scientific, technical and medical applications at wide range of utilization in Russia and abroad.

Determination of the possibility of separation of titanomagnetite and ilmenite in the selective separation of titanomagnetite ores

Experience in the development of iron-titanium ores has shown that their successful processing is possible only with the use of complex combined processing schemes. The possibility of selective extraction of titanomagnetite and ilmenite products during magnetic (electromagnetic) separation is considered during processing of altered disseminated titanomagnetite ores of the Medvedevsky deposit. Purpose of the research is to determine the possibility of separation of microaggregates of titanomagnetite and ilmenite during selective magnetic (electromagnetic) separation of disseminated titanomagnetite ores. Materials and methods. Classification of crushed material with its subsequent separation by magnetic (electromagnetic) properties. Analysis of the distribution of iron and titanium dioxide and the identification of the nature of the disclosure of ore and non-metallic minerals from the standpoint of technological mineralogy. Results. Products of classified ore after magnetic (electromagnetic) separation are characterized by uneven distribution. Most of the material (45,01%) is concentrated in fractions separated at a magnetic field with strength of more than 250 mT. The yield of magnetic fraction is 2,89%. A high content of Femagnetic is characteristically for the products of magnetic separation of titanomagnetite ore obtained at the magnetic field with strength of 10 mT. Generally, titanium dioxide is concentrated in the products of electromagnetic separation separated at a magnetic field with strength of 140 mT. Studies have established that the products obtained at H = 10 mT consist of 37% titanomagnetite aggregates of varying degrees of martitization. With increasing of magnetic field strength, the number of titanomagnetite grains decreases and the content of ilmenite grains increases in the products of electromagnetic separation. In this case at H = 140 mT, free grains (55%) are mainly consist of ilmenite. Conclusions. Analysis of the magnetic separation products showed that with a magnetic field strength of 10 mT it is possible to obtain a product with mainly titanomagnetite composition, and it is possible to obtain a product with mainly ilmenite composition with a magnetic field strength of 140 mT.