Backfill Technologies and Designs for Deep-Level Sylvinite Mining

To reduce intensity of deformation in rocks prone to buckling and plastic deformation, and sensitive to geo- and gas-dynamic phenomena, the authors propose a consolidated backfill technology using salt waste and processing reuse brine at the consumption limits of water-yielding capacity. A set of laboratory tests is carried out to find backfill mixtures adaptable to deep-level potash mining with estimation of deformation characteristics and strength properties of potash salt rocks. New principles and technologies of deep-level sylvinite extraction and backfill material transport by creating such geotechnical structures in stopes which ensure formation of consolidated backfill mass with the mined-out stope space factor close to one. This approach can enhance mine efficiency owing to increased extraction of sylvinite from rib and safety pillars.