cmq abstracts Production of Al-Si Master Alloy by Aluminothermic Reduction of Silica in Molten Cryolite Y.M. Gorji, Semnan University, Semnan, Iran; M. Soltanieh, Iran University of Science and Technology, Tehran, Iran; and A. Habibolahzadeh, Semnan University, Semnan, Iran The influence of the production parameters on the production of an Al-Si master alloy has been investigated by aluminothermic reduction of silica in molten cryolite. Kaolin was employed in molten cryolite as primary sources of silica and alumina. The effect of parameters such as reduction time, kaolin, silica and alumina contents on the silicon reduction coefficient in molten cryolite has been studied. The results indicate that the silicon content of the alloy increases by increasing the reaction time and silica content (up to 8 wt% in molten cryolite) and decreases by increasing the alumina and undissolved silica content of the bath. Kaolin appears to have no effect on the silicon reduction coefficient KSi but increases the reaction rate. Desulphurization Characteristics of Ladle Furnace Slags of a Low Sulphur Steel E. Keskinkilic, A. Geveci and Y.A. Topkaya, Middle East Technical University, Ankara, Turkey In steelmaking, one of the most important parameters for desulphurization is the oxygen potential of the system which can be expressed either by oxygen activity of the steel or by FetO activity of the slag. Removal of sulphur from the steel is enhanced when FetO activity of the slag and thus oxygen activity of the steel decreases. In this paper, ladle furnace slags of a low S steel quality currently produced in Eregli Iron and Steel Works Company (ERDEMIR), Turkey, were studied. The relation between %Decrease αFetO and %DeS (measured) was studied. The percentage of sulphur removal was also investigated using the data of the oxygen activity of liquid steel. Ladle Eye Area Measurement Using Multivariate Image Analysis K.J. Graham, K. Krishnapisharody, G.A. Irons, Steel Research Centre, McMaster University, Hamilton, Ontario; and J.F. Macgregor, McMaster Advanced Control Consortium, McMaster University, Hamilton, Ontario Despite the importance of ladle metallurgy to the overall steel making process, very little has been achieved in the way of advanced ladle control. Limited sensors are available to monitor progress during refining and current control methods involve manual procedures. This paper details a vision-based sensor for analyzing ladle eye dynamics in real time using a multivariate image analysis (MIA) technique based on principal component analysis (PCA). Predictive capabilities of the developed model are demonstrated using previously published cold model data over a wide range of operating variables. Further, preliminary work has confirmed the ability of the sensor for potential use in an industrial setting. Effect of Nozzle Location and Nozzle Capacity on Spray Cooling of Hot Gas in a Horizontal Duct J. L. Xia, J. Järvi, Pori Research Center, Outotec Oyj, Pori, Finland; E. Nurminen, Helsinki University of Technology, HUT, Espoo, Finland; E. Peuraniemi, Outotec Oyj, Espoo, Finland; and M. Gasik, Helsinki University of Technology, HUT, Espoo, Finland The modelling of the spray cooling of hot gas in a horizontal duct is carried out. Three nozzle arrangements are considered: the nozzle is located at the duct wall with the injection in favour of and against gravity (cross flows) and at the central axis (parallel flow). The predicted flow and heat transfer performance between different nozzle arrangements are compared for various nozzle capacities and numerical predictions are verified with simplified analytical solutions of outlet temperature. Results show that some non-vapourized droplets flow out of the duct exit. As far as the cooling effect is concerned, the cross flow with the injection against gravity is the best and the parallel flow appears to be the worst. For a given nozzle capacity, the operation may be more stable (with less flow and thermal fields fluctuation in quasi-steady state) and fewer droplets hit the duct wall for the nozzle arrangement with the injection against gravity. For safe operation, the nozzle should be located about 9 to 10 m ahead of the equipment.
Excerpts taken from abstracts in CMQ, Vol. 46, No. 4. Subscribe—www.cmq-online.ca
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