Influence of Thermal Stability of Quartz and the Particle Size Distribution of Burden Materials on the Process of Electrothermal Smelting of Metallurgical Silicon
The article describes the thermal stability of quartz deposits in Kazakhstan-Aktas and Sarykul. It is established that the quartz of the Aktas deposit is a raw material with low thermal stability, and quartz is of medium-durability at Sarykul deposit. The complex influence of the thermal stability of this raw material on the technological parameters of smelting of technical silicon under experimental industrial conditions of electrothermal melting in a furnace with a capacity of 30 MVA was studied at LLP “Tau-Ken-Temir” (Kazakhstan). A new method for optimizing the smelting of commercial silicon has been developed, even when using raw materials with low thermal stability. The main idea of the method is that the less thermally stable quartz is used, the more the initial size of its pieces should be. Optimum values of the average size of pieces of quartz-Aktas(85-95 mm) and Sarykul-(30-40 mm) are obtained.
Operational Aspects of Silicon Oxidereduction Process and Their Effects on the Material and Thermal Flows Balance in Carbothermic Reactors
The article deals with the influence of operational aspects on the performance of the reduction process in reactors with submerged electrical arc. Experiments were conducted in the large-scale laboratory conditions in one-electrode furnace with a capacity of 200 kVA at Chemical and Metallurgical Institute (Karaganda, Kazakhstan). Also limited industrial research in the furnace with the capacity of 30 MVA at LLP ‘Tau-KenTemir’ was conducted.In the process of the research, evidence was achieved that increasing the interval between the furnace top treatments up to 30 minutes, and achieving a balance between the material and thermal flows in a reactor allow increasing silicon yieldup to 10-15% minimum. Fluctuations in the phase currentstabilize. It was proved that on the basis of the concept of balancing it is possible to bringan industrial reactor out of complex crisis statesrather quickly.
Far-field dispersal modeling for fuel-air-explosive devices
A computer model for simulating the explosive dispersal of a fuel agent in the far-field regime is described and is applied to a wide variety of initial conditions to judge their effect upon the resulting fuel/air cloud. This work was directed toward modeling the dispersal process associated with Fuel-Air-Explosives devices. The far-field dispersal regime is taken to be that time after the initial burster charge detonation in which the shock forces no longer dominate the flow field and initial canister and fuel mass breakup has occurred. The model was applied to a low vapor pressure fuel, a high vapor pressure fuel and a solid fuel. A strong dependence of the final cloud characteristics upon the initial droplet size distribution was demonstrated. The predicted fuel-air clouds were highly non-uniform in concentration. 18 refs., 86 figs., 4 tabs.