GENERATION OF ELECTRICAL ENERGY FROM BLAST INDUCED VIBRATIONS

Abstract

Generation of electrical energy has become a basic aspect in power system because of incremental demands from citizenry in electrical distribution system. Power may be generated in different ways. Numerous developments took place in power generation technology for the generation of electricity, but those are all dependent on conventional sources. In the present research, generation of electrical energy using piezo sensors was done by tapping electrical voltage from undesirable ground vibrations generated from blasts in mines.
Blasting operations in mines and quarries always result in ground vibrations, which are of major environmental concern, to be investigated by the researchers. Studies were carried out in three different limestone mines and two different sandstone bench formations of coal mines, situated in Southern India, to assess and analyze the seismic energy resulting from the blast induced ground vibrations. In total, 116 blast vibration events in limestone formation and 94 blast vibration events in sandstone formation were studied from various blasts. It was observed that there is a potential for tapping of electrical energy from the ground vibrations generated due to blasts carried out in mines and quarries, using piezo sensors. Piezo generator circuits were developed and used in addition to the seismographs at different distances ranging from the short to long range in all mining locations, to tap the ground vibrations. Electrical voltage was tapped from the blast induced ground vibrations during studies, which later was used for running low powered VLSI systems as ambient power source. Also, it was noticed that the obtained electrical potential is in direct proportion to the input vibration intensity.
The range of voltage tapped from ground vibrations is up to 4531.42mV in limestone and 4277.51mV in sandstone formations. Further, the amount of voltage acquired was used to obtain the intensity of blast vibrations. A very good correlation between seismic energy (obtained from ground vibrations using signal processing analysis) and electrical energy (obtained from piezo generator developed) was observed during the studies, i.e. about 99% in both formations. Results also indicated that the working of piezo sensor in tapping ground vibrations is as accurate as traditional ground vibration monitors.