SOUTH AFRICAN SUPPLIERS
n Bulk solids handling : Transporting bulk solids requires an understanding of the bulk flow properties that include angle of inclination , surcharge and repose , flow functions , chute angles , wall friction and solids compressibility ; n Crushing , screening , washing and classification : Paterson & Cooke ’ s process test work includes sample preparation and unit process performance using jaw crushing , rod or ball mills , dry and wet screening , scrubber and washing tests , low intensity magnetic separation and dense media separation , as well as measuring crushing and abrasion indices ; n Metal extraction : Metallurgical test work includes column and tank leach tests , batch and dynamic tests , kinetic flotation tests and bottle roll tests to maximise metal recovery ; n Tailings treatment : The company has extensive experience in dewatering tailings using thickeners and filters and provides the data needed to select the most appropriate dewatering process for the application ; n Mine backfilling : Mine backfilling requires an intimate understanding of the material properties to determine the most appropriate backfilling solution , and this includes knowledge of the material dewatering requirements , pipeline flow behaviour , and strength requirements of the optimum backfill recipe determined from , Paterson & Cooke says , a well-designed test campaign that considers the material properties and the appropriate binders to meet the mining requirements ; n Concentrate and tailings pipelines : Designing long distance pipelines requires a thorough understanding of variations in flow behaviour due to changes in material properties that may affect the performance and longevity of the system ; n Tailings management and disposal : To effectively manage the disposal of tailings requires an understanding of the geotechnical characteristics and the process requirements to dewater and deposit the material onto the disposal facility . This includes geochemical characterisation , permeability and drainage tests , acid base accounting and net acid generation tests ; and n Pilot plant testing : Full scale process performance tests on hydrocyclones , batch , or continuous small scale pilot plant operation are available . The company concluded : “ Our facilities can be modified to suit client specific test requirements and to test vendor equipment and instrumentation to determine their suitability in specific applications .”
Next gen AXXIS raises more global interest
Electronic detonation technology from South Africa continues to push the boundaries of worldclass performance , as the AXXIS Silver™ system from blasting and explosives specialist BME is showing .
A member of the JSE-listed Omnia Group , BME ’ s latest generation AXXIS™ offering includes both the flagship AXXIS Titanium™ solution for large-scale mines and the leaner AXXIS Silver option aimed at the quarrying and construction sectors , as well as the smaller end of the open-pit mining market .
“ The interest from the market already extends globally ,” Tinus Brits , BME Global Product Manager – AXXIS ,” said . “ AXXIS Silver has in fact already been put through its paces in Lesotho and Australia and is gaining attention in Indonesia .”
Soon after being introduced into the Australian market , AXXIS Silver was already detonating some significant blasts under demanding conditions . During one of the blasts , the detonators were submerged under water and mud for four days due to heavy rains . Despite these conditions , no errors or leakage were experienced on the day of the blast , according to BME .
A significant advantage of these electronic detonation systems is that they allow for more controlled blasting in sensitive settings , according to BME ’ s AXXIS Support Manager , Hennie du Preez .
In a recent excavation project in the urban area of Midrand between Johannesburg and Tshwane , AXXIS Silver was used to good effect , he explained .
“ With a road only 20 m from the blast , and a building just 34 m away , we were able to initiate 766 electronic detonators in a highly controlled manner ,” he said . “ This minimised ground vibration and air blast and avoided any fly rock .”
Controlled blasting is becoming more important as many quarries are now seeing encroachment by communities , which demands even safer blasting practices . Electronic initiation systems like AXXIS allow detonators to be accurately initiated within milliseconds of each other , staggering the energy release rather than having five or six holes detonating at the same time . This reduces the charge mass per delay , thereby reducing the resulting vibration .
AXXIS also integrates with BME ’ s blast planning software BLASTMAP™ , so users can simulate each blast before it is implemented . This allows aspects like ground vibration to be predicted in advance to ensure it will be within the required parameters .
The speed at which users can set up and fire the blast has also been improved in the latest AXXIS versions . The blast preparation functions are now built into the logger , which can carry out the programming , scanning and testing . After the detonators have been programmed , the user can start up the controller from the view site and blast within two minutes .
Among BME ’ s design imperatives is the alignment with the United Nation ’ s Sustainable Development Goals – including those related to climate change and energy efficiency . AXXIS allows a blast to achieve levels of rock fragmentation that makes loading , hauling , crushing and milling more efficient , BME claims .
Brits explained : “ Quality blasts reduce energy consumption in energy-intensive downstream processes . This , in turn , reduces carbon emissions from electricity generation – as well as from diesel-powered load and haul equipment .”
The finetuning of detonation delay accuracy in AXXIS systems helps mines and quarries improve their carbon footprints as they pursue their
AXXIS Silver has already been put through its paces in Lesotho ( pictured ) and Australia and is gaining attention in Indonesia
56 International Mining | JANUARY 2023