Enrichment of placer gold ore through Knelson concentrator optimization

Abstract

This study investigates the optimization of placer gold ore processing using a laboratory-scale Knelson concentrator through response surface methodology (RSM) and Box-Behnken experimental design. Fifteen experiments were conducted to assess the effects of three parameters: solid concentration (wt.%), G force (G), and fluidization water flow rate (l/min), on gold grade and recovery. Statistical analyses using Design Expert 13 revealed significant quadratic regression equations for both gold grade and recovery, with high coefficients of determination. The empirical models demonstrated the intricate relationships between the concentrator parameters and process responses. Interpretation of the equations revealed that increasing the solid concentration positively influenced gold grade and recovery, while higher G force and fluidization water flow rate negatively impacted these parameters. Moreover, synergistic effects were observed between certain parameter pairs, indicating the complex interplay of factors influencing gold concentration and extraction efficiency. The study highlights the importance of understanding the separation mechanisms within the Knelson concentrator, especially in the presence of flaky gold particles alongside spherical particles. Insights gained from this research provide valuable guidance for optimizing placer gold ore processing operations, ultimately enhancing efficiency and sustainability in mineral processing practices.