Kinetic Study on Decomposition and Dissolution of Limestone in Converter Slag
The kinetic behaviour of limestone decomposition and dissolution in converter slag at temperatures in the range of 1300–1400 °C was studied. The influence of decomposition reaction on the lime dissolution rate was also investigated. The rate-limiting steps of decomposition and dissolution of limestone in converter slag were determined on the basis of shrinking core hypothesis. The experimental results indicate that a mixed controlling mechanism of chemical reaction and heat conduction through the produced lime layer should be considered for the limestone decomposition in converter slag. The rate-controlling mechanisms of the dissolution of produced lime differ during the various sub-processes. In addition, examination of the lime microstructure at higher slag temperature revealed that cracks are formed in decomposed lime layer; lime dissolution is promoted by molten slag and penetrates through these cracks.
KeywordsKinetic behaviour Limestone decomposition Dissolution rate Converter slag
The authors gratefully acknowledge the National Natural Science Foundation of China (51574065, 51574066, 51774072 and 51774073) and the National Key R&D Program of China (No. 2017YFB0304201, 2017YFB0304203, 2016YFB0300602) which have made this research possible.
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