Evaluation of blast fragmentation effects on jaw crusher throughput

Abstract

The fragmentation rate and particle size distribution of the muckpile after blasting have important influences on the performance of subsequent mining activities such as loading, hauling, crushing, grinding, and the overall costs of the mine. Drilling and blasting are important steps in the chain of mining processes, and its results affect the efficiency of downstream processes accordingly. There is an increasing body of blasting research that indicates the significant impacts in mining downstream processes. Within the scope of this study, a series of blasts were conducted in a sandstone quarry, and the throughput of the jaw crusher was recorded after each blasted rocks are fed. These measurements consisted of analysis of the particle size distribution of each muckpile after shots, and the assessment of particle size distributions of each truck—load fragmented rock. Digital image processing method was used for the assessment of the particle size distribution of blasted rock. The fragmentation results then were paired with the crusher throughput values, and series of regression analysis were done in order to understand the effects of blast fragmentation on crusher throughput. The analysis includes the relationship between P₂₀, P₅₀, P₈₀, and P_top values of size distributions and the crusher throughput results. Depending on the correlation degree of each relationship, effects of each size distribution parameter on crushing performance were discussed. Established empirical equations with reliable correlation coefficients can be used to estimate the crusher performance depending on fragmentation results of a blast and therefore, and blast designs can also be modified.