Study on the energy distribution of high voltage pulse in water and solid phases in electrical disintegration

Recently, electrical disintegration (ED) has been paid attention in the field of mineral processing and resources recycling since it can bring on preferential breakage at phase boundary. However, the mechanism has been not yet well known. We carried out fundamental experiments using artificial binary (cupper/epoxy resin) sample in order to clarify the energy consumption at the two kinds of phenomena of water and solid breakdown in the ED and to clarify the driving force of preferential breakage. In the experiments, we measured the numbers of pulse applied time to break the binary sample by changing the position of samples between the electrodes and estimated the energy distribution in the above two phenomena. We also measured the voltage and current changes with elapsed time in the ED and made a theoretical calculation of the above energy consumption. As a result, the rate of energy consumption at water breakdown increased gradually as increasing the distance between upper electrode and sample surface, d, and reached to 95 % of total energy consumption in the condition of d >7 mm at 30 kV of applied voltage. We also found out that the optimum d value was 3-5 mm for realizing the best efficient breakdown.