Improving the reliability of fluidized bed alumina calciners by suitable refractory lining selection

Abstract

Refractories are key components for the productivity of a calcination unit. Unexpected halts caused by refractory failures directly affect the production plan and lead to considerable financial losses (lost income, additional material purchasing and installation). In parallel, planned overhauls are relatively longer due to the time associated with equipment cooling down, inspection, descaling, application of new linings and dry-out process. Typically, the overhaul time ranges from 12 to 40 days, reaching volumes of 250 ton of installed refractory and with costs in the order of US$ 1.5–3 million. Due to the importance of refractory working life, there is a need to develop a systemic approach that considers data from laboratory, plant trial and large-scale implementation studies in order to extend working life and deliver cost savings. This paper will present various examples of materials replacement in critical areas of the calciner, and the attained performance during operations.