Rutile acts as a target phase for the titanium (Ti) recovery from Ti-bearing blast furnace slags (Ti-BFS) due to its special properties. In this study, using single hot thermocouple technique (SHTT), we investigated the crystallization behaviors of the Ti-BFS and the target rutile precipitation behaviors where both the holding temperature, the basicity (mass ratio of CaO to SiO2) and the P2O5 content were considered. We found that basicity has a vital influence on the crystallization behaviors and rod-like rutile only formed with lower basicity. As the basicity increased, the primary phase would transform from rutile to perovskite. As the basicity was 0.5, with the temperature increasing, the growth rate of rutile length initially increased, followed by a decrease with further increasing holding temperature. Thus, the growth rate of rutile had a maximum value of 7.74 µm/s at 1260 °C. Furthermore, the rutile growth followed a one-dimensional template, and the P2O5 content had an important impact. By increasing the content of P2O5, the incubation time of the rod-like rutile got decreased, suggesting that the rutile precipitation got much easier.
Ti-bearing slags In situ study Crystallization behaviors Rutile Chemical modification
This is a preview of subscription content, log in to check access.
Wang LP et al (2004) Distribution and production status of titanium resources in China. Chin J Rare Metals 28:265–267Google Scholar
Wen L, Zhang JZ (2011) Properties on titanium-bearing blast furnace slags. J Iron Steel Res Int 23:1–3Google Scholar
Zhang L et al (2006) Effect of perovskite phase precipitation on viscosity of Ti-bearing blast furnace slag under the dynamic oxidation condition. J Non-Cryst Solids 352:123–129CrossRefGoogle Scholar
Zhang L et al (2006) Dynamic oxidation of the Ti-bearing blast furnace slag. ISIJ Int 46:458–465CrossRefGoogle Scholar
Li J, Zhang ZT, Wang XD (2011) Crystallization behavior of rutile in the synthesized Ti-bearing blast furnace slag using single hot thermocouple technique. ISIJ Int 51:1396–1402CrossRefGoogle Scholar
Li J et al (2013) Influence of basicity and TiO2 content on the precipitation behavior of the Ti-bearing blast furnace slags. ISIJ Int 53:1696–1703CrossRefGoogle Scholar
Li J, Zhang ZT, Wang XD (2012) Precipitation behaviour of Ti enriched phase in Ti bearing slag. Ironmak Steelmak 39:414–418CrossRefGoogle Scholar
Sun Y et al (2015) Co-modification and crystalline-control of Ti-bearing blast furnace slags. ISIJ Int 55:158–165CrossRefGoogle Scholar
Sun Y et al (2014) The effect of P2O5 on the crystallization behaviors of Ti-bearing blast furnace slags using single hot thermocouple technique. Metall Mater Trans B 45:1446–1455CrossRefGoogle Scholar
Li Z et al (2016) Effect of Al2O3 addition on the precipitated phase transformation in Ti-bearing blast furnace slags. Metall Mater Trans B 47:1390–1399CrossRefGoogle Scholar
Kashiwaya Y et al (1998) Development of double and single hot thermocouple technique for in site observation and measurement of mold slag crystallization. ISIJ Int 38:348–356CrossRefGoogle Scholar
Kashiwaya Y et al (1998) An investigation of the crystallization of a continuous casting mold slag using the single hot thermocouple technique. ISIJ Int 38:357–365CrossRefGoogle Scholar