Improving the Operational Availability of Hydro Alunorte Calciners by Proper Refractories Maintenance Management

The aluminaAlumina calcining process takes place at high temperatures (up to 1100 °C) and, thus, the vessels are lined with refractory materials. Unexpected production halts or the extension of the maintenance time length have a relevant impact on the additional costs and unrealized revenue. Therefore, enhancing the refractories working life and its application speedSpeed is essential. Considering this, the objective of this work is to present the implemented improvements attained during the last few years, in terms of materials selection and quality controlQuality control, design and the gains in application time and return to operationsOperation. The achieved results indicated relevant gains regarding the reduction in the lining wear (and less unexpected halts) and speedSpeed up of the application steps (mainly the decrease of the drying/heat up curve). By following this approach, Hydro Alunorte maintenance area is increasing the reliability on the applied material, and contributing to more stable and long-lasting operationsOperation.