Abstract:
The determination of a reasonable cut-off grade plays a crucial role in ore drawing in caving stopes, directly affecting the ore recovery indicators and thus the overall economic benefits of resource recovery in mines. To accurately obtain an economically reasonable cut-off grade indicator, this paper comprehensively considers all production activities in the series of processes from the discharge of raw ore underground to the formation of fine powder and even tailings, and constructs a cut-off grade determination model based on the entire mining and beneficiation chain. This model covers the full cost of ore processing from mining to sales, and thus calculates the cut-off grade. Due to different ore selling prices, the Dahongshan Iron Mine adopts this model to calculate the cutoff grade under different ore selling prices to guide underground ore extraction. A total of approximately 3.5 million tons of low-grade stockpiled ore has been recovered, greatly improving the resource recovery rate and generating significant economic benefits. Currently, there are many mines in China that adopt this caving mining method, and this cut-off grade calculation model and the successful practice of the Dahongshan Iron Mine can provide reference for other mines in comprehensive resource utilization.