Pulsed powered plasma blasting for lunar materials processing

This paper discusses the design, construction, and performance of a prototype plasma blasting power system and blasting probes. In this system, a capacitor is charged over a long period of time at low current (power), then discharged in a very short pulse at very high current to break blocks of concrete or large rocks. Scalable prototypes of the plasma blasting probes for electrically powered pulsed plasma rock blasting were also designed and constructed. The blasting system is able to provide pressures well above the tensile strengths comparable to those of common rocks, i.e. granite (10-20 MPa), tuff (1-4 MPa) and concrete (7 MPa). The system was successfully tested by reducing concrete specimens into small rubble with blasting probe delivered net energy levels starting at 9 kJ and greater. Tests on concrete and granite rock test samples are reported.