Intermediate Drives in Belt Conveyor Systems for Efficiency Improvement: Implications for More Sustainable Material Transport in Mining – A State-of-the-Art Review

Abstract Belt conveyor systems play a central role in modern mining as energy-efficient alternatives to truck-based haulage for bulk material transport. However, increasing transport distances and higher throughput requirements are pushing conventional conveyor designs towards technical limits, particularly regarding belt tensile strength and system scalability. Intermediate drives have therefore emerged as a key solution to improve overall system efficiency. This state-of-the-art review systematically analyses intermediate drives in belt conveyor systems with a focus on efficiency improvement and their implications for more sustainable material transport in mining. A total of 137 scientific publications were reviewed to identify research trends, classify existing drive concepts, and assess operational performance under real and simulated conditions. Results show that intermediate drives can significantly reduce belt tension forces and improve power transmission in long-distance conveyor systems, enabling lighter belt constructions and improved energy utilisation. These effects may contribute to more sustainable mining logistics through reduced material intensity and higher transport efficiency. However, only few concepts – most notably tripper drives – have achieved widespread deployment and proven long-term reliability, while emerging approaches such as driving idlers remain insufficiently validated in field conditions. Consequently, adoption of intermediate drives is still low. Future research should focus on supporting industrial implementation and technology transfer. In particular, simulation-based evaluation combined with techno-economic and cost-benefit analyses can provide decision support for identifying viable applications and reducing investment uncertainty, thereby enabling broader adoption and improved sustainability outcomes in mining transport systems.