Nonferrous ore concentration

MelikGaikazyan V.I., Yemelianova N.P., Kozlov P.S., Yushina T.I., Lipnaya E.N. As to investigation of foam flotation process and selection of reagents on the basis of their mechanism. Report 1. Reason of selected methods to investigate process
Three components of particle–bubble contact hardening, which arise in appearing the external tearing force f under the dynamic foam flotation conditions, have been analyzed. Bubble surface bending near the contact perimeter, increase in contact angle q, and local growth of surface tension σ on the bubble surface near the perimeter of its contact with the particle to be detached can be referred to them. Three possible mechanisms of bubble surface bending due to the gravitation and reagents: classic, hysteretic, and capillary are found with the help of the equation of the capillary physics and experiments. Necessary reagent properties facilitating such bending under the effect of f, namely their ability to selective hydrophobization of particle surface and to local growth of surface tension s on the stretched bubble surface, are found. Two groups of simple research techniques of the process and reagent selection that simulate the foam flotation process are recommended: 1) for estimation of reagent capability to vary the wettability of particle surface – flotation tests in foam and foamless apparatuses, measurement of tearing forces, time of bubble adhesion to particles, and wetting angle; 2) aside from the above, the techniques of relaxation curves recording and foamforming property estimating (for reagents acting predominantly on the bubble surfaces). The effect of capillary gas pressure bubbles of different size on the particle tearing force from them and the invariant property of these forces on σ during slow tearing is shown.
Key words: foam flotation, surface tension, capillary pressure, equations of capillary physics, adhesion forces, inertial tearing forces, flotation tests, wetting angles, relaxation curves, wetting hysteresis, nonequilibrium.

Yevdokimov S.I., Panshin A.M. Choice of process to concentrate clinker from the Waelz process of zinc cakes
Aged clinker of the zinc production at OAO “Electrozinc” is the subject of the investigation. Its primary precious components are copper (0,67 %), zinc (5,0 %), lead (1,0 %), iron (21,71 %), and coke fines (10 % C). The chemical compounds composing the clinker are characterized by density, magnetic and flotation properties. These distinctions are the basis for the combined methods of mechanical preparation for application in clinker processing. The results of the investigations of competitive clinker processing flow diagrams are given. They are notable for the structure and sequence of applying different beneficiating methods. The process flow diagram is recommended, which is characterized by open the grinding cycle and different processing of sand and classifier overflow. The comparison of commercial production value and expenses related to its manufacture shows the economic expediency of clinker processing.
Key words: clinker, magnetic separation, iron concentrate, skimping, coke fines, flotation concentration, heavy nonferrous metals, cost of processing.

Extractive metallurgy of nonferrous metals

Parfyonov O.G., Pashkov G.L. Distinctive features of subchloride metallurgy of titanium
The conditions of gasphase reactions to reduce titanium tetrachloride to metal state by aluminum subchloride have been investigated in the approximation of the equilibrium thermodynamics. The reduction process was found to be of threshold character by three parameters: temperature, amount of subchloride, and radius of metal surface. The parameters being above the found threshold values and the amount of inert gas in the gaseous mixture uniquely designate the titanium and its aluminide yield. The conditions are found when production of titanium pure in aluminum is possible. A comparative analysis of the advantages and disadvantages of subchloride and vaporphase metallothermic methods of reduction of titanium is given.
Key words: titanium, aluminum, aluminide, nucleation, chloride, subchloride, reduction reaction.

Chuikin A.Yu., Zaikov Yu.P. Lowtemperature aluminum electrolysis in bath made of corundum highalumina concrete
Tests of lowcement highaluminous corundum concrete as lining material in aluminum electrolysis from the KF–AlF3–Al2O3 melt at 750 °С have been carried out. It is found from the results of 100hour experiment that the process takes place in stable way with sufficiently high current yield. No concrete lining corrosion was observed for this time. The studied material does not affect notably the quality of produced metal. As can be seen from the results of the chemical analysis before and after the tests, the calcium and potassium contents meet the requirements of GOST 110692001 to primary aluminum of commercial purity. The investigated highaluminous concrete can be recommended as lining material in the design of aluminum electrolyte pots with lowtemperature potassiumcontaining electrolyte.
Key words: aluminum electrolysis, potassium cryolite, highaluminous concrete, structural materials, corrosion.

Kravtsova E.D., Gildebrandt E.M., Frizorger V.K. Plastic properties of coke–pitch compositions
The results of studying the rheological behavior of cokepitchy compositions containing 55 % pitchy and coke dust of different grainsize composition with particle size of no less than 0,212 mm are given. It is shown that the dustpitchy compositions can be characterized as Bingham systems at the temperatures simulating the anode mass production parameters (433–493 К). It was found that the dispersion of solid phase, coke charge, and temperature affect their rheological properties. The following quantitative flow characteristics: yield point, plastic viscosity, and apparent activation energy of flow have been measured.
Key words: selfbaking anode, pitch, coke, cokepitchy composition, viscosity, plastic properties, rheological properties, yield limit.

Extractive metallurgy of less-common and precious metals

Strizhko L.S., Loleit S.I., Zakharova V.I. Recovery of precious metals by biosorbents from industrial solutions and wastewaters
The chemical composition of different industrial solutions from the Shchelkovo Works for Secondary Precious Metals is evaluated. The excess of heavy metal contents in relation to gold and silver is found to be more than 1000 times. Microbial biomasses of different systematic groups have been tested to extract Au and Ag from the solutions of high salt background. The expediency of selective extraction of noble metals from such complex solutions is shown. The behavior of heavy metals in the course of sorption from individual solutions within the range of pH 1,0–6,0 of the medium has been studied. The decisive value of solution pH (within 1,0–3,0) on the selective Ag extraction from industrial solutions was found. The fact that silver and heavy metals are attributed to different metal groups regarding the sorption degree by microorganisms depending on medium pH was confirmed. Specific behavior of biomass cells in acid medium facilitates the separation of these elements. Biosorption Ag extraction from process solution over granulated lincomycin biomass has been tested under the industrial conditions. Average extraction degree was the following (in %): Cu – 8,1, Ni – 4,2, Zn – 4,0, Fe – 15,5. The losses of biosorbent were about 70 g/m3.
Key words: biosorption, microbiowaste, silver, heavy metals, industrial solutions.

Metal forming

Kargin V.R., Pastushenko T.S., Kargin B.V. Mode of deformation in case of thinwalled tube sinking through rotated reducing dies
An investigation of the mode of deformation in thinwall pipes in the sinking process through turning drawing dies in plane perpendicular to the drawing axis has been carried out. An equation system, which allows with the help of computer to find stress fields and deformations necessary for designing sinking through turning drawing dies, was described.
Key words: drawing die, sinking, stress, thinwall pipe, mode of deformation.

Parshin S.V. Multipass drawing of finned tubes
The use of pipe profile shaping processes where the deformation is executed for a few stages allows us to obtain a number of beneficial effects. There is a sufficiently wide class of shaped pipes, which, due to their specific geometry, cannot be produced differently than by multipass profile shaping. A procedure is proposed to estimate the mode of deformation in the course of drawing and the pipe material ductility life.
Key words: multipass drawing, mode of deformation, deformation center, plasticity life.

Surface engineering. Multifunctional films

Dolgopolov N.A., Rodin A.O., Simanov A.V., Gontar’ I.V. Copper diffusion along aluminum grains
Copper grainboundary diffusion in aluminum has been studied within a range of Т = 300ё400 °C. The studies have been carried out with the scanning electron microscope with an addon device for micro Xray spectral analysis. Al2Cu compound was found to be in equilibrium with the solid solution at these temperatures. The sdDgb triproduct (where s is the segregation coefficient, dis the grain boundary width, Dgb is the grainboundary diffusion coefficient) was calculated from the Fisher solution by two methods: copper concentration along the grain boundary depending the penetration depth was determined and angles in the concentration profile apex were measured with the help of light microscope., The sdDgb value amounted to 5,1·10–11 exp(– 102/(RT)) m3/s in the first case and 1,4·10–11 exp(– 94/(RT)) m3/s in the second case. The obtained results are compared with the literature data few in number.
Key words: grain boundaries, copper diffusion, aluminum.

Process control and automation

Ishmetiev E.N., Zykov I.E. Development of fuzzy logics model and controller for copper sulfide concentrate smelting process control in Vanyukov furnace
A process to develop a fuzzy control model is described for copper sulfide concentrate smelting in Vanyukov furnace (in the PV2 complex of Copper Smeltery at the Transpolar Affiliate of OAO “Norilsky Nickel” MiningMetallurgical Integrated Works). The fuzzy model as polynomials and the controller diagram developed on its basis are given.
Key words: fuzzy control model, Vanyukov furnace, survey plan, expert information acquisition.

Chronicle

Yury Abramovich Lainer is 75 years old