Blast Design for Improved Productivity using a Modified Available Energy Method

In this work, a new drilling and blasting design methodology is introduced and applied at a case study mine to improve productivity. For the case study copper mine, a blast diameter of 203 mm is proposed to be used in the ore zone to meet the new required production rate of 90mtpa from 75mtpa. Currently, the Konya and Walter’s model is used to generate drilling and blasting design at a blasthole diameter of 172 mm. The new drilling and blast design approach is advantageous in the sense that it generates a lower specific drilling value and predicts an average fragment size compared with the current method being used. In this regard, a modified available energy blast design method that incorporates the blastability index of ore zone in the calculation of the input powder factor is introduced. The results of the blast design simulations at a 203 mm blasthole diameter shows that the modified available energy model generates a drilling and blasting design with a specific drilling value that is 15.3% less than that generated by the Ash’s and Konya and Walter’s models. Further, the modified available energy model generates a blast design with a predicted average fragment size that is 3.4% smaller than that generated by the Ash’s model, and 6.7% smaller than that generated by the Konya and Walter’s model.