Pumpable emulsion explosives have been available to surface and underground massiveudmining operations for decades and through their unique properties offer significantudadvantages through improved safety, reliability and performance. Despite their advantageousudproperties the benefits of pumpable emulsions have been unavailable to narrow reef miningudoperations due to the void in technology necessary for their successful implementation withinudthe challenging environment.udThe purpose of the following research report is to evaluate the viability of pumpableudemulsion explosives for use in South African narrow reef mining operations. By approachingudthe problem from multiple perspectives, this research report aimed first to propose audtheoretical framework and suite of equipment suitable for the implementation of pumpableudemulsions within the narrow reef environment. Through the development of this equipment,udcontrolled tests could be undertaken on the proposed narrow reef emulsion formulations andudpumpable emulsion technology to obtain the necessary understanding of the performance ofudthe system under controlled conditions. Once an understanding had been obtained for theudcontrolled performance of the system, a field study could be undertaken in order to compareudthe performance of the new pumpable emulsion system with available explosives within theudunderground mining industry. Through the results obtained a comparison could be made ofudthe blasting efficiency and feasibility of pumpable emulsions when compared to existingudexplosives within the narrow reef environment.udGiven the vast difference in underground narrow reef and massive mining operations,udfundamental changes were necessary with regard to emulsion technology prior to theudsuccessful implementation of the narrow reef emulsion system. Following the development ofudthe system, controlled explosives tests allowed for optimisation of the pump technology asudwell as recommended daily practices. Blast results achieved in field trials with the narrowudreef emulsion system allowed for improved blasting efficiency while reducing explosivesudcosts per tonne broken. While blast results and efficiencies improved throughout pumpableudemulsion trials, variances in daily blasting practices including the use of stemming,udovercharging and varying priming practices influenced the results obtained. Further testing isudtherefore recommended in order to determine the influence of variables on the resultsudobtained such that a specific increase in blasting efficiency can be determined.
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