The aluminium industry has expressed, in recent years, a high growth rate. During aluminium production, several solid wastes are generated. The ceramic industry has great potential for the reuse of waste because it can incorporate heterogeneous waste from different origins and compositions without a significant depreciation of its product quality. Mozambique Aluminium (MOZAL) generates 5 tons/day of residue and a viable method for its disposal has not yet been found. The main objective of the present work is to develop an alternative for the reuse of the spent pot lining (SPL) residue from the production of carbon anodes at the MOZAL factory. The use of the waste was promoted through its incorporation into ceramic masses. For this purpose, the effect on linear shrinkage, weight loss, bulk density, water absorption and compressive strength was evaluated by varying the firing temperature (850 to 950˚C), firing time (15 to 45 minutes) and SPL content (0 to 20%). The minimum values established by the NM 127 2009 standard were compared with the results obtained from the compressive strength in the partial replacement of clay by SPL. The optimal processing conditions were found to be firing at 900˚C for 30 minutes with 10% of SPL content. The incorporation of SPL up to 15% has a positive influence and can be used to produce solid bricks (up to 10% for all classes and 15% for B and C classes). However, it is recommended that replacements do not exceed 15% to ensure good resistance results according to the minimum values.
KeywordsClayCeramic MassSPL ResidueCarbon Anodes
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