Interactions of vanadium-rich slags with crucible materials during viscosity measurements
Slag chemistry is important for the assessment of flow behaviour of slags produced during gasification of coal and coal–petroleum coke blends. Slags containing vanadium species react readily with the crucible and spindle materials used for viscosity measurements. Interaction of vanadium-rich slags with various materials has been investigated in order to obtain a better understanding of the impact of containment materials on the resulting slag chemistry and viscosity. The bulk and phase compositions of two petroleum coke slags in Al2O3, Mo, Pt and Ni crucibles produced under different laboratory conditions were analysed, and kinetics of slag composition changes at 1400 °C were determined. Mechanisms of the slag interactions with crucibles are described. They involve exchanging of crucible and slag constituents, formation of interfaces with distinct compositions, and continuously changing phase equilibria in the system. For slag processed in Ni and Pt crucibles, reduction of Fe and Ni from oxide to metallic form occurs and is followed by dissolution into the crucible materials. Viscosity of slags with Mo, Ni and Al2O3 crucibles are determined in the temperature range 1200–1500 °C. Resulting changes in the bulk composition of the processed slag has an impact on the slag viscosity. At given temperatures, viscosities of the slags produced in different crucibles are different. The impact of crucible materials and their applicability in viscosity measurements of high vanadium-containing slags are also discussed in order to define the optimal conditions.
KeywordsGasification Viscosity Measurement Petcoke Liquid Slag Slag Sample
The authors acknowledge the facilities and technical assistance of the Australian Microscopy & Microanalysis Research Facility at the Centre for Microscopy and Microanalysis, The University of Queensland.
- 9.Duchesne MA, Ilyushechkin AY, Macchi A, Anthony EJ (2010) Proceedings of the 27th annual international Pittsburgh coal conference, p 38Google Scholar
- 12.Iida T (2002) In: Aune RE, Sridhar S (eds) Proceedings of the mills symposium, London, National Physical Laboratory, Teddington, UKGoogle Scholar
- 14.Hu H, Reddy RG (1990) High Temp Sci 28:195Google Scholar
- 15.Muller J, Erwee M (2011) In: Jones RT, den Hoed P (eds) Southern African Pyrometallurgy 2011, Southern African Institute of Mining and Metallurgy, JohannesburgGoogle Scholar
- 16.Hla SS, Roberts DG, Harris DJ (2011) Final report for ACARP project CCSDRes001Google Scholar
- 18.Bird RB, Stewart WE, Lightfoot EN (2002) Transport phenomena, 2nd edn. Wiley, New YorkGoogle Scholar
- 19.Roberts D, Ilyushechkin A, Tremel A, Beavis P, Kochanek M, Harris D (2010) Final Report for ACARP Project C17060BGoogle Scholar