Use of Biochar to Improve Biomethanization in Anaerobic Co-Digestion

Biosolids are a byproduct of wastewater treatment that is used for biogas production. In Panama, biosolids remain untapped as a sustainable source of energy; but they are disposed in landfills, which could become an environmental trigger. In this sense, the anaerobic co-digestion of biosolids generated in the Juan Díaz Wastewater Treatment Plant was evaluated at the batch reactor level, with the addition of biochar from rice husks, which was obtained by gasification. This work presents the methodological criteria used and the satisfactory findings obtained from the investigation. The results obtained from the anaerobic co-digestion using biochar, had an increase of 21% with respect to the test without biochar. The methane content of the trial with biochar (55.88%) was also higher compared to the trial without biochar (53.46%). Another finding was the regulation of alkalinity provided by the biochar, which allowed maintaining the pH in favorable ranges for co-digestion. These findings show the potential of biochar to generate high biological stability in anaerobic co-digestion and therefore an improvement in biogas production. However, it is necessary to continue researching on the use of biochar, to optimize anaerobic co-digestion processes.