This article assesses the impact of industrial noise emitted by the Sangarédi bauxite mine, operated by the Compagnie des Bauxites de Guinée (CBG), on local communities. Noise levels measured in this area frequently exceed the accepted norms, with 69.56% of recorded readings exceeding the critical limit of 115 dB. Moreover, nine measurements even exceeded 120 dB between May 1 and July 24, 2023, indicating significant noise exposure for residents. Daytime noise levels regularly exceed the 55 dB standard, while night-time levels are generally within the prescribed limits. Analysis of the noise generated by ore trains passing through the surrounding villages shows that, of the nine values measured, five (55.55%) are below permissible levels. However, despite some compliant measures, the high noise levels recorded continue to cause significant adverse health impacts for local residents. These impacts include stress, hearing problems and other serious health complications, demonstrating the urgent need for effective noise abatement measures to protect the health and well-being of local communities. The results reinforce the importance of continuous monitoring and rapid intervention to mitigate these noise nuisances and improve the quality of life of the populations affected.

Good alumina production using the Bayer process depends on the regularity of the alumina dissolution parameters, as failure to control these factors leads to a drop in alumina yield. This work has enabled us to identify and propose solutions to the anomalies linked to alumina dissolution. An analysis of the dissolution parameters (temperature, liquor concentration, residence time and saturation rate) shows that the alumina yield from January to December was irregular. This fluctuation in alumina yield remains the same for all the parameters studied. Chemical analysis was used to provide results for certain parameters. These included spectral analysis, pH meter analysis and methrom analysis of samples taken from the etching plant. These analyses showed the different behaviours of the concentration of the liquor and the content of the different bauxite constituents. An analysis of the graphs shows that the parameters vary according to the plant’s instructions. All the results obtained show the need to regulate the alumina dissolution parameters. Better management of these factors will help to improve alumina yield.