Selective breakage of mineralised synthetic particles by high voltage pulses. Part 2: Interactions between mineralised particles in a multiple-particle system

Abstract Part 1 of this study presented evidence of high voltage pulse (HVP) selective breakage induced by metalliferous grain-embedded synthetic particles in a two-particle system. However, in reality, there are multiple particles containing minerals of varying conductivity in a pulse treatment zone and questions remain as to how this type of situation affects the HVP breakage characteristics. Consequently, an experimental study was conducted in a three-particle treatment system, consisting of two mineralised particles embedded with metalliferous grains of different electrical conductivities and one barren particle with no metalliferous grain, subjected to one pulse loading. It was found that the electrical breakdown channel travels preferentially through the particles containing the highest conductivity minerals, resulting in a higher probability of selective breakage, a finer progeny size distribution and a greater energy transfer efficiency for these particles, but impairing the breakage probability of the particles containing the less conductive minerals. The presence of multiple mineralised particles in the pulse treatment zone reduces the probability of misclassification of the barren particles, which means it could enhance the waste rejection rate in a multiple-particle treatment configuration using HVP technology for ore pre-concentration.