Application of electromagnetic field in anaerobic biodigestion in batch reactors

Abstract

Anaerobic digestion processes with biogas production are widely used for organic waste treatment with an emphasis on energy recovery. Some recent studies have demonstrated the influence of magnetism on microbiological activity. These indicate a possible influence on the efficiency of anaerobic digestion. Thus, technologies that act in anaerobic digestion enhancement can contribute to the improvement of treatment of organic compounds. The present study aimed to verify the influence of a constant electromagnetic field on the anaerobic digestion in anaerobic reactors fed with glucose (2 g/L) at 37 ± 2 °C. In each experiment, reactors were operated with a constant electromagnetic field of 5, 7.5, and 10 mT. The inoculum was granular sludge from an anaerobic treatment plant in a non-selective media culture. Biogas production, chemical oxygen demand (COD), and solids removal were measured during the experiment. Results showed differences in methane production of 21.5% and in COD removal of 15% in the tests with an electromagnetic field of 7.5 mT. These results signs for the viability of the application of a constant magnetic field as a biostimulation agent.