Résultats exploitables Analysis of open pit and underground mining of fluorspar and barite lode deposits An analysis has been carried out on the possiblities of mining fluorspar and barite lode deposits by small scale mining methods. Fundamental analysis included: investigations of the market; a definition of the size of small scale mining; development of the geometry of the mine model; investigation of problems; and analysis of practical examples of transition from open pit to underground mining. A comparison of methods of open pit mining reveals that a transition to underground mining (sublevel stoping with cemented backfill) with ramp in the ore technique is the most economical choice but only when the mineral contained in the ramp is exploited ater the transition in order to minimize losses. The influence of the environmental impact assessment on mining operations was also investigated. A decision method including economic and ecological parameters in the decision process for transition from open pit to underground mining was developed. Its application on model mines showed that often, if the decision for transition is taken at an earlier stage of operation, the environmental impact of the operation is a lot smaller and the economics of the mine are only affected to a small degree. Results showed that small scale mining can only be performed economically on deposits with high ore contents and thicknesses. The geometry of the deposit should have a great horizontal and a limited vertical extension. The mining operation should be carried out with used equipment and transport activities by subcontractors to minimize costs. The economics of the whole operation is heavily influenced by beneficiation. In the case of refilling a pit, analysis and calculations of the dimensions of the natural crown pillar and concrete blocks have also been carried out. Recherche de données OpenAIRE... Une erreur s’est produite lors de la recherche de données OpenAIRE Aucun résultat disponible
