BIOGAS PRODUCTION BY ANAEROBIC CO-DIGESTION OF AGRO-INDUSTRIAL WASTE AND CRUDE GLYCEROL

Abstract

The use of fossil fuels continues to represent a significant percentage of energy production in Mexico; this, together with the generation of considerable amounts and poor disposal of organic waste, has contributed greatly to the emission of greenhouse gases, exacerbating the problem of environmental pollution. In Mexico City’s central supply center alone, more than 500 Mg of organic waste is produced daily, and its disposal is not the most appropriate. An alternative for the correct disposal of this waste is the anaerobic digestion process, which, in addition to being an environmentally friendly technology, offers benefits such as the possibility of obtaining value-added products such as biogas, which represents a viable alternative to the use of fossil fuels. In this study, waste generated in Mexico City’s central supply center was collected for use in anaerobic co-digestion to produce biogas using crude glycerol obtained as a byproduct of the biodiesel plant located in the same center. Throughout the bioprocess lasting 12 weeks, with a hydraulic retention time of 33.3 ± 0.04 days and an organic matter removal efficiency of 77.6 %, it was possible to obtain perfectly flammable biogas with a methane composition between 60 and 70 %, with an average production of 0.576 ± 0.084 m³ d^-1.