Title:
Valorization of Primary Aluminum Industry By-Product in Cement Materials
Author(s):
Victor Brial, Laurent Birry, and Claudiane Ouellet-Plamondon
Publication:
Symposium Paper
Volume:
362
Issue:
Appears on pages(s):
841-853
Keywords:
alternative supplementary cementitious materials; recycled material; reactivity tests
DOI:
10.14359/51742013
Date:
6/17/2024
Abstract:
Approximately 22 kg of spent pot lining is generated (SPL) per ton of aluminum produced by electrolytic cells. Untreated SPL is classified as hazardous industrial waste due to its hydroreactive nature and the presence of leachable cyanide and fluoride compounds. After treatment with the Low Caustic Leaching and Liming (LCL&L) industrial process, the refractory portion of the SPL is transformed into an inert material called LCLL. This project analyzed the use of LCLL as a cement binder. The reactivity of LCLL was studied using the compressive strength activity index, and RILEM R3 tests. The results showed that LCLL is composed of stable crystalline phases such as corundum, albite, and nepheline, and contains graphite. The improvement of LCLL reactivity was explored by calcination and the addition of synthetic fluorite, also from the LCL&L process. The results showed a significant improvement in reactivity with the formation of a larger amount of reactive amorphous phases with high silica and alumina content with optimum fluorite content of 10%. Calcined LCLL showed similar reactivity to fly ash, without retarding effect, with compressive strength equivalent to cement at 112 days and the formation of a new phase rich in carboaluminate.