...2007:224 CIV M ASTER’S TH E SI S Study of the reactions between iron ore slag and refractories Julien Zimmermann MSc PrograMMeS in engineering Materials Technology (eeigM) Luleå University of Technology Department of Applied Physics and Mechanical Engineering Division of Material Mechanics 2007:224 CIV • ISSN: 1402 - 1617 • ISRN: LTU - EX - - 07/224 - - SE Summary: For the fabrication of iron ore pellets at LKAB (Luossavaara-Kiirunavaara AB), one of the methods used is to sinter the pellets in a rotary kiln. This Kiln has a drift temperature of 1250°C in average. During this process a coating, causing the wear of the refractories materials, is formed, inducing expensive maintenance periods. The aim of this work is to find the reaction that takes place between the Slag and the bricks, in order to find the parameters that have to be changed to improve the bricks lifetime in the kiln. The use of bricks with higher alumina content is one of the solutions, but it is expensive. The influence of Alkalis and especially Na2O has been studied before in inert atmosphere. In this work it will be studied in air as well as the influence of the alumina content of the brick. Experiments were performed in air atmosphere, using powder samples that have been compressed into pellets. The devices used to characterize the reaction and the product of the reaction were: Kanthal furnace, X-ray diffraction (XRD), dilatometer, differential scanning calorimetry and thermogravimetry (DSC/TG)...
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