Heavy minerals secondary processing estimation at pulp hydrotransport in the pipeline
Introduction. When developing placers containing small amounts of heavy minerals, it is advisable to use the technology of hydraulic mining which includes secondary processing of these minerals essential for sand preliminary processing. Research aim is to estimate heavy minerals secondary processing in pipeline bottom layer and single this layer out of the general flow at pulp hydrotransport when developing placers with dredgers. Methodology. Based on the regularities analysis of pulp hydrotransport, sands granulometric distribution and the results ofphysical simulation of the process in laboratory conditions, the analytical substantiation of hard minerals secondary processing parameters is carried out. The main provisions of secondary concentration are as follows: at sand hydrotransport, bottom layer of large and heavy particles arises in the pipeline, the particles drag or roll over. At that, particles distribution by size and density in the cross section ofpulp flow corresponds to Rozin-Rammler equation. Results. The results are presented of the laboratory research of weighing heavy particles from the bottom sediment, measuring weighing speed for heavy minerals and quartz sand. The obtained results were approximated by the formula. The example is given of heavy minerals secondary processing possibility analytical estimation. Summary. The use of the secondary processing without change of a field development process flow diagram will significantly improve the efficiency of the subsequent processing processes when developing placer deposits.