An integrated assessment of geomechanical and energy parameters for deep pit reclamation via regenerative conveyors: a Kryvyi Rih case study

Abstract

The object of research is the technological process of rock mass handling. During active mining, this process required moving the overburden from the pit to surface terrain dumps. Once extraction was completed, the operation shifted to mine reclamation through in-pit dumping. At that stage, the stored rock mass was relocated from external dumps back into the mined-out space using regenerative conveyor systems. The main problem to be solved involved reducing the energy footprint of such reclamation operations without sacrificing the geomechanical stability of the dump slope. Conventional haulage methods relied heavily on fossil fuels, leading to carbon emissions and high operating costs. This economic and environmental burden demanded a shift toward technologies capable of capturing the gravitational potential energy of the relocated rock mass.

The research combined limit equilibrium analysis for slope stability evaluation with numerical modeling of the interconnected energy and geomechanical balance. To pinpoint exactly where gravity acted on each rock volume, a step-by-step vertical discretization of the benches was applied, coupled with the geometric centroid method.

Modeling of the reclamation system designed for a 500-meter-deep pit in Ukraine's Kryvyi Rih region proved that regenerative conveyors are capable of accumulating up to 542.36 million kWh of energy (1.24–1.34 kWh/m³). Calculations revealed a 6.9% technological gap from the theoretical limit. The centroid method yielded zero mathematical error, whereas the area bisection technique underestimated the energy potential by 11.7%.

These findings offered a practical framework for designing reclamation and decarbonization strategies at deep open-pit mines. By leveraging the patented technological solution (Ukrainian Patent No. 158796), mining operators could transform standard environmental cleanup operations into a revenue-generating energy asset.