A review of state-of-the-art techniques for the determination of the optimum cut-off grade of a metalliferous deposit with a bibliometric mapping in a surface mine planning context

In terms of the global share, 95% of the non-metallic minerals, 90% of the metallic minerals, and about 60% of coal are being mined out through surface mining methods. In a mining operation, the grade-tonnage distribution of the deposit necessitates that not all of the material inside the open pit can be treated. Given this variability, it is critical to identify ore and waste elements correctly. The global population is expected to increase from 8 billion in 2022 to more than 9.7 billion in 2050. World metal consumption increases at around 3.2% per year, driving trade and economic diversification. Therefore, to guarantee a continuous supply of the minerals from the metalliferous surface mining industry in terms of techno-economic concerns, cut-off grade (COG) optimization is the key. The economic requirement aims towards the maximization of the return on investment, while techno-economic sustainability aims towards the maximization of resource recovery. Optimization of COG for surface mine design has come a long way in the last 60 years, primarily using analytical models based on the traditional methodology. In the past five years, non-conventional evolutionary algorithms have been extensively used. However, the analytical methods can be credited with the maximum amount of work, yet none can provide optimal outputs. This review article presents techniques, advancements, limitations, difficulties, bibliographic analysis, and potential future research paths in COG optimization for surface mine planning.

Automated summary

In terms of global mining, most non-metallic minerals (95%), metallic minerals (90%), and coal (about 60%) are extracted through surface mining methods. It is crucial to accurately identify ore and waste elements due to the grade-tonnage distribution in mining operations. With the expected increase in global population from 8 billion in 2022 to over 9.7 billion in 2050, along with a yearly 3.2% increase in metal consumption, the optimization of cut-off grade (COG) is key to ensure a continuous supply of minerals and maximize resource recovery.