Development of advanced eco-friendly spinel-containing castables to replace chromite-based refractories

• Grant number: 21/00114-2
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: June 01, 2021
• End date: February 14, 2025
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Nonmetallic Materials
• Principal Investigator: Victor Carlos Pandolfelli
• Grantee: Otávio Henrique Borges
• Host Institution: Centro de Ciências Exatas e de Tecnologia (CCET). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil
• Associated scholarship(s): 23/00386-8 - Compositionally complex ceramics as an alternative to chromium-based refractory aggregates, BE.EP.DR

Abstract

The secondary steel refining process takes place in steel ladles where the refractory lining is exposed to severe conditions. Until the mid-1990s, most of the materials used for this application contained chromite, which is comprised of several spinel-like phases. Despite its efficiency and low cost, it was discovered that chromite gives rise to toxic waste after its disposal. Therefore, alternatives to this raw material became to be studied. Currently, the use of spinel-containing (MgAl2O4) refractories has been established as the main alternative to those containing chromium, however, their corrosion resistance, cost, and thermal shock resistance have not matched yet. In this regard, the formulation of refractories containing other spinel-like phases - and their mixture - is promising due to its inherent high corrosion resistance and distinct thermal expansion coefficient, which induces microcracking in the material, leading to high thermal shock resistance. Although its use in refractories has not been extensively studied, the spinel ZnAl2O4 is a promising option as it presents high refractoriness (> 1900ºC), it can be obtained at temperatures below 1000ºC, and it is produced by the reaction of non-toxic and relatively cheap oxides. Therefore, this project will study the ceramic systems formed by Al2O3, ZnO, MgO, and CaO to develop refractory castables comprised of distinct types of spinel-like phases formed in situ, aiming at producing a material capable of withstanding the severe conditions of which steel ladle linings are subjected, contributing to cost and environmental damage reductions. (AU)

Scientific publications

(7)

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

BORGES, O. H.; SARDELLI, J. A. P.; NETO, C. PAGLIOSA; DA LUZ, A. P.; PANDOLFELLI, V. C.. ZnO and MgO as inducers of spinel-like phase formation on alumina-based castables. Journal of the European Ceramic Society, v. 42, n. 15, p. 8-pg., 2022-12-01. (21/00114-2)

BORGES, O. H.; COURY, F. G.; MUCHE, D. N. F.; PANDOLFELLI, V. C.. Eco-friendly design of complex refractory aggregates as alternatives to the magnesia-chromite ones. Journal of the European Ceramic Society, v. 43, n. 14, p. 14-pg., 2023-11-01. (21/00114-2)

SARDELLI, J. A. P.; BORGES, O. H.; NETO, C. PAGLIOSA; PANDOLFELLI, V. C.. Is the in-situ ZnAl2O4 formation an alternative for magnesia-alumina spinel zero-carbon shaped refractories?. CERAMICS INTERNATIONAL, v. 49, n. 17, p. 8-pg., 2023-09-01. (21/00114-2)

BORGES, O. H.; FALSETTI, L. O. Z.; SOUZA, D. A.; LOPEZ, F.; PANDOLFELLI, V. C.. Alkali-based components as slag fluidizers in steelmaking processes: A thermodynamic assessment. CERAMICS INTERNATIONAL, v. 50, n. 2, p. 5-pg., 2023-12-05. (21/00114-2, 22/00378-2)

BORGES, O. H.; CARDOSO, A. L. F.; MOREIRA, M. H.; KLEIN-GUNNEWIEK, R. F.; PANDOLFELLI, V. C.. Conventional and microwave-assisted sintering of ZnO-containing CAC-bonded alumina-based refractory castables. Journal of the European Ceramic Society, v. 43, n. 14, p. 9-pg., 2023-11-01. (21/00251-0, 21/00114-2)

BORGES, OTAVIO HENRIQUE; COURY, FRANCISCO GIL; BRACHHOLD, NORA; ANEZIRIS, CHRISTOS GREGORIUS; PANDOLFELLI, VICTOR CARLOS. Designing eco-friendly alternative microstructures for magnesia-chromium aggregates. Journal of the American Ceramic Society, v. 107, n. 12, p. 12-pg., 2024-08-21. (21/00114-2, 23/00386-8)

PINTO, V. S.; LUZ, A. P.; BORGES, O. H.; PANDOLFELLI, V. C.. Binder effect on ZnAl2O4-containing high-alumina refractory castables. CERAMICS INTERNATIONAL, v. 48, n. 8, p. 9-pg., 2022-03-16. (21/00114-2)