EVALUATION OF IN-PIT CRUSHING AND CONVEYING (IPCC) SYSTEMS PRODUCTIVITY IN OPEN PIT MINES

Abstract

Haulage of materials in Open-pit mines contributes to approximately 40%-60% of the total operational costs. Current stricter environmental conditions, an increase in depths and size of open-pit mines, an increase in labour costs, and fuel costs have made the conventional truck and shovel system extremely expensive. This predicament has motivated search for alternative material haulage options in open-pit mines. In-Pit Crushing and Conveying (IPCC) system has been regarded as the best plausible alternative for the conventional transportation approach. However, the usage of IPCC has been limited to only a few mines due to limited knowledge on the IPCC performance as a system and other technical factors of the system. This thesis investigated and evaluated the productivity performance of the four types of IPCC systems. The study utilizes mine productivity index (MPi) as the measure of overall productivity of each IPCC type. The thesis develops a model aided by MATLAB that computes the system MPi holistically from input variables of availability, utilization, and performance. This model was applied to a quarry case study from Mombasa Cement Limited. It was found that the FIPCC had the highest truck fleet of 55. The large truck fleet had impact on increasing the overall system availability but decreasing the system performance and utilization. In overall, the MPi for the FIPCC, SFIPCC, SMIPCC, and FMIPCC was obtained as 67.13%, 69.02%, 70.52%, and 71.52%, respectively. Apparently, the FMIPCC is the best placed IPCC for the utilized case study. The in-depth investigation of the state of art of the IPCC systems and the evaluation of the IPCC systems based on the number of trucks, shovels, system availability, utilization, performance, and MPi provide vast knowledge on IPCC. This increases the likelihood of it being considered as better alternative haulage option in open pit mines.