Controlling Backbreak and Improving Technical and Economic Parameters in Mishdovan Iron Ore Mine

One of the major problems related to blasting operations in open-pit mines is the formation of cracks on the benches behind the last row of blast holes or back breakes. Power Deck blasting has been introduced as a new and alternative method for conventional blasting, which improves blasting results by explosive energy utilization enhancement. In this technique, there is an air deck at the end of the blasting hole which decreases or eliminates sub-drilling. Power Deck blasting reduces charge per delay in the same conditions as conventional blasting and charge per delay is one of the most effective parameters of back break. In this study, back break caused by conventional and Power Deck blasting was evaluated in the Mishdovan iron ore mine. Back break in Power Deck blasting was reduced by 16.4% and 55% in iron ore and stone waste respectively as compared to back break in conventional blasting. Power Deck blasting could therefore be effectively used as a controlled blasting technique to obtain stable faces. Also after loading and hauling the fragment size, it was found that both methods have no significant differences in flat floors. Eventually, the Power Deck method reduced powder factor and specific drilling by 28.5% and 9%, respectively. In addition, holes productivity improved by 9% in Power Deck blasting compared to conventional blasting.