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Continuous Treatment of Materials by Electrical Impulses
Margarita Mezzetti, Oleg Popov, Holger Lieberwirth
Technische Universität Bergakademie Freiberg, Institute of Mineral Processing Machines and Recycling Systems
Technology, Germany
Erik Anders
Technische Universität Dresden, Institute of Mechatronic Engineering, Germany
Sandra Weyrauch, Nils Reichelt
Haver Engineering GmbH, Germany
ABSTRACT: The processing of mineral ores by electrical impulses has aroused the interest of researchers
worldwide, particularly due to its selective nature and the potential applications deriving from it. A significant
number of investigations in laboratory units have contributed to the dissemination of this technology. However,
one of the constraints of the batch-operating lab units is their limited capacity. The application of this technology
as continuous units with larger capacity has been missing. With the objective of transferring the electrical
impulse technology into semi-industrial applications, a continuous machine with a throughput capacity from
up to 500 kg/h has been developed. Initial tests on several materials (granodiorite, tungsten ore and slags) have
been conducted. An overview of the initial results is presented here.
Keywords: electrical impulses, high voltage impulses, continuous processing
INTRODUCTION
About 60 years ago when Russian researchers observed and
reported the effect of high-voltage electrical discharges on
materials the scope of potential applications was not clear.
For several decades the investigations were dominated by
Russian research groups.
The high-voltage electric impulse technology basically
utilizes the differential behaviour of materials when exposed
to high-voltage electrical discharges. At present, two possi-
bilities for the applications of high voltage impulses have
developed: either as a direct discharge through the material
or as the effect of a shock wave generated in water.
The former occurs when the high voltage impulses are
initiated with an extremely short rise time, usually below
500 ns or even shorter, and this process has been referred to
in the literature as electro dynamic fragmentation, electri-
cal comminution, electro impulse technology, HV pulses,
among others. The latter occurs when the rise time exceeds
the 500 ns, hence the dielectric strength of water is lower
than that of the solid material and this is known as shock
wave comminution or electro-hydraulic fragmentation. A
diagram illustrating the two possibilities is presented in
Figure 1 (a).
A diagram illustrating the basic working principle is
presented in Figure 1 (b). In simple terms, some elements
are needed for using this technology: a high voltage elec-
trode, an earth electrode, the solid material and a dielectric
fluid, for example, water.
Continuous Treatment of Materials by Electrical Impulses
Margarita Mezzetti, Oleg Popov, Holger Lieberwirth
Technische Universität Bergakademie Freiberg, Institute of Mineral Processing Machines and Recycling Systems
Technology, Germany
Erik Anders
Technische Universität Dresden, Institute of Mechatronic Engineering, Germany
Sandra Weyrauch, Nils Reichelt
Haver Engineering GmbH, Germany
ABSTRACT: The processing of mineral ores by electrical impulses has aroused the interest of researchers
worldwide, particularly due to its selective nature and the potential applications deriving from it. A significant
number of investigations in laboratory units have contributed to the dissemination of this technology. However,
one of the constraints of the batch-operating lab units is their limited capacity. The application of this technology
as continuous units with larger capacity has been missing. With the objective of transferring the electrical
impulse technology into semi-industrial applications, a continuous machine with a throughput capacity from
up to 500 kg/h has been developed. Initial tests on several materials (granodiorite, tungsten ore and slags) have
been conducted. An overview of the initial results is presented here.
Keywords: electrical impulses, high voltage impulses, continuous processing
INTRODUCTION
About 60 years ago when Russian researchers observed and
reported the effect of high-voltage electrical discharges on
materials the scope of potential applications was not clear.
For several decades the investigations were dominated by
Russian research groups.
The high-voltage electric impulse technology basically
utilizes the differential behaviour of materials when exposed
to high-voltage electrical discharges. At present, two possi-
bilities for the applications of high voltage impulses have
developed: either as a direct discharge through the material
or as the effect of a shock wave generated in water.
The former occurs when the high voltage impulses are
initiated with an extremely short rise time, usually below
500 ns or even shorter, and this process has been referred to
in the literature as electro dynamic fragmentation, electri-
cal comminution, electro impulse technology, HV pulses,
among others. The latter occurs when the rise time exceeds
the 500 ns, hence the dielectric strength of water is lower
than that of the solid material and this is known as shock
wave comminution or electro-hydraulic fragmentation. A
diagram illustrating the two possibilities is presented in
Figure 1 (a).
A diagram illustrating the basic working principle is
presented in Figure 1 (b). In simple terms, some elements
are needed for using this technology: a high voltage elec-
trode, an earth electrode, the solid material and a dielectric
fluid, for example, water.