Aggregate breakdown by high voltage electrical pulses

摘要

A method of liberation of minerals from rock matrices and of metallic inclusions from slags by their detachment from matrices as a result of applying high voltage electrical pulses with specific parameters to develop discontinuities at interfaces of minerals and metallic fragments with different permittivity, electrical conductivity and acoustic impedance is described. The final stage of liberation takes place in mechanical compressive disintegration and particulation by crushing and comminution of composite solids. The parameters of pulses and design of liberation chambers for efficient liberating detachment of valuable components of different types of composite solids is described. Original aggregates may be greater than 100mm in size and ore broken down to 20mm and subsequently 74-100žm. Pulses are delivered with a uniform frequency or in a burst regime in the range of 30-550kV, with a rise in time of voltage being 20-50ns, and a peak current of 3-10kA.